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Sample records for alborz mountains northern

  1. Enhanced moment tensor retrieval: a case study in the Alborz Mountains, Northern Iran

    NASA Astrophysics Data System (ADS)

    Donner, Stefanie; Rößler, Dirk; Ghods, Abdolreza; Krüger, Frank; Strecker, Manfred; Landgraf, Angela; Ballato, Paolo

    2010-05-01

    Seismotectonic and seismic hazard analysis are crucial tasks in, often increasingly, densely populated, seismically active regions. The understanding of earthquake source mechanisms is an important key element for such analyses. Seismic moment tensors provide a general description of the physical processes and the magnitude of earthquakes. The feasibility of moment tensor retrieval is controlled by several factors, such as wavefield modelling, source location, and station distribution. Inappropriate velocity models and inhomogeneous station distribution limits the inversion and the availability of seismic moment tensors in many regions worldwide. The Alborz Mountains of northern Iran are a tectonically active, bivergent orogen in the Arabia-Eurasia collision zone. It is located between the aseismic blocks of the South Caspian Basin and Central Iran. A complex and not well understood system of strike-slip and thrust faults accommodates NNE-SSW oriented shortening. There are indicators that deformation in the high sectors of the Alborz Mountains is partitioned into reverse and left-lateral strike-slip faulting. Studies of earthquake source mechanisms will provide further insights in the complex fault geometry, their kinematic behaviour, and the tectonics of this intracontinental orogen. In addition, the internal domain of the central Alborz seems to be affected by very young, active transtension. To date, a heterogeneous seismic network with non-uniform distribution and a lack of appropriate methods have prevented detailed and comprehensive moment tensor studies in this region. So far, only 26 seismic moment tensors are available in the Harvard CMT catalogue since 1976. This restriction is due to the magnitude threshold of M4.5 for data processing and due to low data availability. Uncertainties in earthquake location are significant. Depth determination is sometimes impossible. Therefore, earthquakes cannot be associated with faults and the recent kinematic behaviour

  2. Dinosaur tracks from the Jurassic Shemshak Group in the Central Alborz Mountains (Northern Iran)

    NASA Astrophysics Data System (ADS)

    Abbassi, Nasrollah; Madanipour, Saeed

    2014-04-01

    The Shemshak Group includes alternating layers of coal-bearing shale and siliciclastic sediments in the Baladeh area in the central Alborz Mountains of northern Iran. A diverse and abundant Jurassic dinosaur footprint assemblage is now recognized in the group, which is Toarcian to Bajocian in age in the northern Baladeh. This is the first report of a diverse dinosaur ichnoassemblage from Iran that includes the footprints of sauropods. These tracks can be assigned to three groups of trackmakers: theropods, ornithopods and sauropods. Those of theropods are typically tridactyl in shape, their trackways reflecting bipedal movement. Theropod footprints are very abundant in both northern and western Baladeh. The studied theropod tracks themselves are divided into three major dimensional groups. The medium sized footprints (footprint length, 11-15 cm) are abundant and have a stride length, digit and pace angles like the coelurosaurs footprints and trackway. Theropod footprints were identified as similar to Schizograllator otariensis, Talmontopus tersi and Wildeichnus isp. Ornithopod footprints are tridactyl with rounded and thick toes and belong to bipeds. Some didactyl imprints were also observed. Skin imprints were well preserved in these footprints. The ornithopod tracks resemble Jiayinosorupus johnsoni, as well as Velociraptorichnus sichuanensis for didactyl footprints. Sauropod footprints found in the western part of Baladeh are assigned here to Eosauropus isp., which are pentadactyl pes imprints of a quadruped. The assemblage from Iran resembles similar associations from eastern Asia.

  3. Assessing tectonic and climatic causal mechanisms in foreland-basin stratal architecture: insights from the Alborz Mountains, northern Iran

    NASA Astrophysics Data System (ADS)

    Ballato, Paolo; Strecker, Manfred

    2015-04-01

    The southern foreland basin of the Alborz Mountains of northern Iran is characterized by an approximately 7.3-km-thick sequence of Miocene sedimentary rocks, constituting three basin-wide coarsening-upward units spanning a period of 106 years. We assess available magnetostratigraphy, paleoclimatic reconstructions, stratal architecture, records of depositional environments, and sediment-provenance data to characterize the relationships between tectonically-generated accommodation space (A) and sediment supply (S). Our analysis allows an inversion of the stratigraphy for particular forcing mechanisms, documenting causal relationships, and providing a basis to decipher the relative contributions of tectonics and climate (inferred changes in precipitation) in controlling sediment supply to the foreland basin. Specifically, A/S > 1, typical of each basal unit (17.5-16.0, 13.8-13.1 and 10.3-9.6 Ma), is associated with sharp facies retrogradation and reflects substantial tectonic subsidence. Within these time intervals, arid climatic conditions, changes in sediment provenance, and accelerated exhumation in the orogen suggest that sediment supply was most likely driven by high uplift rates. Conversely, A/S < 1 (13.8 and 13.8-11 Ma, units 1, and 2) reflects facies progradation during a sharp decline in tectonic subsidence caused by localized intra-basinal uplift. During these time intervals, climate continued to be arid and exhumation active, suggesting that sediment supply was again controlled by tectonics. A/S < 1, at 11-10.3 Ma and 9-6-7.6 Ma (and possibly 6.2; top of units 2 and 3), is also associated with two episodes of extensive progradation, but during wetter phases. The first episode appears to have been linked to a pulse in sediment supply driven by an increase in precipitation. The second episode reflects a balance between a climatically-induced increase in sediment supply and a reduction of subsidence through the incorporation of the proximal foreland into the

  4. P-wave Local Earthquake Tomography in the Central Alborz Mountains, Iran

    NASA Astrophysics Data System (ADS)

    Mostafanejad, A.; Hosein Shomali, Z.

    2010-12-01

    The Alborz Mountain ranges in the southern margin of the Caspian Sea, as a part of the Alpine- Himalayan orogenic belt is an arc of parallel synclines and anticlines. Among the major tectonic and geological features of the Alborz Mountains are the Damavand quaternary volcano, and active and seismic faults like the Mosha, and North Tehran faults. In this study, the first 3D P-wave velocity model of the upper crust in the Central Alborz Mountains is obtained using a local travel-time earthquake tomography method. A data set of 895 earthquakes recorded on a local 19 station short-period network between 1996 and 2006 provided by the Iranian Seismological Centre (ISC) is used in this inversion. The result of tomography shows considerable velocity anomalies in this region. These anomalies show remarkable features in the vicinity of the Mosha and North Tehran faults, as well as in the Damavand volcanic area. In depth of 15 kilometer a low velocity region is observed parallel to the above two mentioned faults. This can be caused by the crushed rocks along these two faults. In the place of splitting North Tehran fault from the Mosha fault, a very noticeable low velocity anomaly represents intense fracturing in rocks. In the Damavand volcanic area and in the northern side of the summit an anomalous high velocity body found to the depth of 20 kilometer. According to its considerable correlation with the position of the old Damavand cone, it is related to the older and crystallized magma chamber of the Damavand volcano. A low velocity anomaly exactly beneath the present cone to the depth of seven kilometer, with another low velocity anomaly in depth of 10 to 20 kilometer constitutes the present magma chamber of the Damavand volcano.

  5. The growth of a mountain belt forced by base-level fall: Tectonics and surface processes during the evolution of the Alborz Mountains, N Iran

    NASA Astrophysics Data System (ADS)

    Ballato, Paolo; Landgraf, Angela; Schildgen, Taylor F.; Stockli, Daniel F.; Fox, Matthew; Ghassemi, Mohammad R.; Kirby, Eric; Strecker, Manfred R.

    2015-09-01

    The idea that climatically modulated erosion may impact orogenic processes has challenged geoscientists for decades. Although modeling studies and physical calculations have provided a solid theoretical basis supporting this interaction, to date, field-based work has produced inconclusive results. The central-western Alborz Mountains in the northern sectors of the Arabia-Eurasia collision zone constitute a promising area to explore these potential feedbacks. This region is characterized by asymmetric precipitation superimposed on an orogen with a history of spatiotemporal changes in exhumation rates, deformation patterns, and prolonged, km-scale base-level changes. Our analysis suggests that despite the existence of a strong climatic gradient at least since 17.5 Ma, the early orogenic evolution (from ∼36 to 9-6 Ma) was characterized by decoupled orographic precipitation and tectonics. In particular, faster exhumation and sedimentation along the more arid southern orogenic flank point to a north-directed accretionary flux and underthrusting of Central Iran. Conversely, from ∼6 to 3 Ma, erosion rates along the northern orogenic flank became higher than those in the south, where they dropped to minimum values. This change occurred during a ∼3-Myr-long, km-scale base-level lowering event in the Caspian Sea. We speculate that mass redistribution processes along the northern flank of the Alborz and presumably across all mountain belts adjacent to the South Caspian Basin and more stable areas of the Eurasian plate increased the sediment load in the basin and ultimately led to the underthrusting of the Caspian Basin beneath the Alborz Mountains. This underthrusting in turn triggered a new phase of northward orogenic expansion, transformed the wetter northern flank into a new pro-wedge, and led to the establishment of apparent steady-state conditions along the northern orogenic flank (i.e., rock uplift equal to erosion rates). Conversely, the southern mountain front

  6. The gabbro (shoshonitic)-monzonite-granodiorite association of Khankandi pluton, Alborz Mountains, NW Iran

    NASA Astrophysics Data System (ADS)

    Aghazadeh, Mehraj; Castro, Antonio; Omran, Nematallah Rashidnejad; Emami, Mohamad Hashem; Moinvaziri, Hossien; Badrzadeh, Zahra

    2010-05-01

    The Khankandi pluton forms part of a group of gabbro-granodiorite intrusions in the Alborz Mountains of NW Iran. A petrographical and geochemical study of this plutonic association reveals the existence of several magmatic cycles with different origins and slight differences in age. The oldest cycle (C1) is represented by granodiorites. A second cycle (C2) is formed by a gabbro-monzonite association, with a clear shoshonitic affinity, that dominates most of the intrusive volume. Gabbros and monzonites form a co-magmatic association. Zircons from the monzonites were analyzed by LA-ICP-MS for U-Pb dating. An average age of 28.9 Ma, ranging from 23.7 to 33.6 Ma was obtained. Gabbros, monzonites and granodiorites share a nearly common isotopic ratio for Sr and Nd. Both initial Sr and Nd ratios are clustered within a narrow range from 0.7045 to 0.7047 for the 87Sr/ 86Sr ratio and ɛNd from 1.46 to 1.89. Comparison with experimental studies, together with mantle-like isotopic ratios and comparisons of REE patterns, points to an origin by variable melting rates from a common metasomatised mantle source for gabbros and monzonites. Melting of a subducted mélange is suggested for the granodiorite magmas predating the gabbro-monzonite intrusion. The two sources, a metasomatised mantle and ascending silicic plumes, are direct consequence of subduction.

  7. Structural and drainage pattern evolution of the Alborz Mountains (N Iran) inferred from provenance data and magnetostratigraphy

    NASA Astrophysics Data System (ADS)

    Ballato, P.; Landgraf, A.; Strecker, M. R.; Friedrich, A.; Tabatabaei, S.

    2007-12-01

    with dominant volcanoclastic pebbles up to U3, where an important change occurs with the appearance of low-grade metamorphic clasts, carbonates, and intrabasinal sandstones. Faster accumulation rates combined with fine-grained facies and variations in sandstone petrography suggest tectonically controlled flexural loading associated with erosional unroofing. The composition of conglomerate clasts indicates the southward propagation of the Alborz deformation front coupled with the erosion of an adjacent source and the onset of basin inversion and clast recycling. In addition, our data suggest that the locus of tectonic activity and unroofing shifted forward and backward and/or that the shortening rate varied through time. Interestingly, the accumulation rates available for northern foreland basin in the realm of the South Caspian Basin, do not record any important changes earlier than Pliocene time. This suggests that either the flexural load was focused on the southern foreland rather than the Caspian side during the Miocene or that most of the sediments eroded from the Alborz were delivered to the southern sectors before the Pliocene. In any case, important drainage pattern reorganization must have taken place before the Pliocene. This reorganization appears to be coeval with of the onset of pronounced exhumation at 7-6 Ma.

  8. 3D joint inversion modeling of the lithospheric density structure based on gravity, geoid and topography data — Application to the Alborz Mountains (Iran) and South Caspian Basin region

    NASA Astrophysics Data System (ADS)

    Motavalli-Anbaran, Seyed-Hani; Zeyen, Hermann; Ebrahimzadeh Ardestani, Vahid

    2013-02-01

    We present a 3D algorithm to obtain the density structure of the lithosphere from joint inversion of free air gravity, geoid and topography data based on a Bayesian approach with Gaussian probability density functions. The algorithm delivers the crustal and lithospheric thicknesses and the average crustal density. Stabilization of the inversion process may be obtained through parameter damping and smoothing as well as use of a priori information like crustal thicknesses from seismic profiles. The algorithm is applied to synthetic models in order to demonstrate its usefulness. A real data application is presented for the area of northern Iran (with the Alborz Mountains as main target) and the South Caspian Basin. The resulting model shows an important crustal root (up to 55 km) under the Alborz Mountains and a thin crust (ca. 30 km) under the southernmost South Caspian Basin thickening northward to the Apsheron-Balkan Sill to 45 km. Central and NW Iran is underlain by a thin lithosphere (ca. 90-100 km). The lithosphere thickens under the South Caspian Basin until the Apsheron-Balkan Sill where it reaches more than 240 km. Under the stable Turan platform, we find a lithospheric thickness of 160-180 km.

  9. Quaternary evolution of mechanical fault-linkage between the North Tehran Thrust (NTT) and Mosha Fasham Fault (MFF), Alborz Mountains, Iran

    NASA Astrophysics Data System (ADS)

    Landgraf, A.; Ballato, P.; Strecker, M. R.; Friedrich, A.; Tabatabaei, S. H.

    2006-12-01

    The kinematic relationship between the neighboring MFF and the NTT is an open question in the fault interaction during the late Cenozoic evolution of the Alborz Mountains. Despite numerous Quaternary faults and their importance for hazard mitigation, the interaction and linkage between these structures are not understood. The ENE-striking NTT is a frontal thrust that delimits the Alborz Mountains to the south, but no instrumentally recorded earthquakes are known here. The E-striking MFF, with a double-bend toward a NW- strike in its central part, is located within the Alborz Mountains. Sinistral motion along its eastern part is corroborated by microseismicity and fault kinematic data, documenting ongoing transtension. Four possible kinematic scenarios may be inferred for both fault systems: (1) each is a separate entity without interaction, (2) progressive eastward propagation of the NTT and linkage with the MFF, resulting in a "master" fault, (3) a "triple junction" with three interacting blocks or (4) a transpressional duplex involving the NW- prolongation of the NTT as frontal, and the ENE-striking NTT segments as lateral ramps between the E-striking east-central and westernmost MFF. The eastern MFF is characterized by sinistral offsets and stream deflections. However, these phenomena are absent in the central-western fault branch. Structural observations along the eastern, slightly north-convex NTT imply dip-slip faulting, where Eocene volcanic units were thrust onto Plio-Pleistocene conglomerates. In addition, fluvial knickpoints, narrow bedrock channels, fluvial terrace remnants, and wineglass-shaped canyons in the hanging wall suggest Quaternary uplift along this fault. However, there must have been a Pleistocene kinematic change along the NTT, involving sinistral reactivation as shown by 80m stream-offsets and horizontal striations on dip-slip faults. NE-trending ravines are sigmoidally shaped, suggesting conjugate shearing by shortening oblique to the

  10. Post-Cimmerian (Jurassic-Cenozoic) paleogeography and vertical axis tectonic rotations of Central Iran and the Alborz Mountains

    NASA Astrophysics Data System (ADS)

    Mattei, Massimo; Cifelli, Francesca; Muttoni, Giovanni; Rashid, Hamideh

    2015-04-01

    mechanism is proposed for the origin of the curved Alborz Mountains, which acquired most of its curvature in the last 8 Myr.

  11. Wolf-livestock interactions in the northern Rocky Mountains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Since reintroduction in 1995, gray wolf populations in the northern Rocky Mountains have increased dramatically. Although rough tallies of livestock death/injury losses resulting from wolf predation are made each year, we know almost nothing about the indirect effects of wolf-livestock interactions...

  12. Wolf-cattle interactions in the northern Rocky Mountains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Since gray wolf reintroduction in 1995, wolf populations in the northern Rocky Mountains have increased dramatically. Incidents of wolf predation on livestock have increased with wolf populations. Although rough tallies of livestock death or injury losses caused by wolf predation are made each yea...

  13. Late Paleozoic paleotectonics of the northern Rocky Mountain region

    SciTech Connect

    Peterson, J.A. . Dept. of Geology)

    1993-04-01

    The present-day configuration of northern Rocky Mountain foreland uplifts and basins evolved mainly by middle to late Tertiary time. Many of these structures, however, were inherited from Paleozoic and early Mesozoic tectonic episodes and thus have a long history of influence on sediment source terranes, clastic and carbonate facies distributions, thickness relationships, and diagenetic processes. New structural growth, and renewed older growth, were particularly important during late Paleozoic time, approximately coincident in time with growth of the Ancestral Rocky Mountains. Some features tend to trend with, or are sub-parallel to elements of the Ancestral Rocky Mountains, including the Laramie-Casper Big Horn high, the Powder River, Bighorn, and Wind River sags, and the Alliance-Denver basin. Late Paleozoic growth of these features, and perhaps others, undoubtedly was affected by stresses associated with the Ancestral Rocky Mountains episode. Interpretations, however, depend on careful stratigraphic and sedimentary facies analyses.

  14. Deciphering the Tectonic History of the Northern Transantarctic Mountains

    NASA Astrophysics Data System (ADS)

    Hansen, Samantha; Graw, Jordan; Brenn, Gregory; Kenyon, Lindsey; Park, Yongcheol; DuBay, Brian

    2016-04-01

    The Transantarctic Mountains (TAMs) are the largest non-compressional mountain range in the world, and their structure plays a key role in the climatic and tectonic development of Antarctica. While numerous uplift mechanisms for the TAMs have been proposed, there is little consensus on their origin. Over the past three years, we have operated a network of 15 broadband seismic stations within a previously unexplored portion of the northern TAMs. Using data collected by this array, we have undertaken numerous studies to further assess the crustal and lithospheric structure beneath the mountain range and to differentiate between competing origin models. Receiver functions indicate crustal thickening inland from the Ross Sea coast but comparable crustal thickness beneath the TAMs and the East Antarctic plateau, indicating little evidence for a substantial crustal root beneath the mountain range. Body and surface wave analyses show a pronounced low-velocity anomaly beneath Terror Rift, adjacent to the TAMs, and extending beneath Victoria Land in the upper mantle. Together, these findings support a thermally-buoyant source of uplift for the northern TAMs and broad flexure of the East Antarctic lithosphere.

  15. Dust Allergens within Rural Northern Rocky Mountain Residences

    PubMed Central

    Weiler, Emily; Semmens, Erin; Noonan, Curtis; Cady, Carol; Ward, Tony

    2015-01-01

    To date, few studies have characterized allergens within residences located in rural areas of the northern Rocky Mountain region. In this study, we collected dust samples from 57 homes located throughout western Montana and northern Idaho. Dust samples were collected and later analyzed for dust mite allergens Der f 1 and Der p 1, Group 2 mite allergens (Der p 2 and Der f 2), domestic feline (Fel d 1), and canine (Can f 1). Indoor temperature and humidity levels were also measured during the sampling program, as were basic characteristics of each home. Dog (96%) and cat (82%) allergens were the most prevalent allergens found in these homes (even when a feline or canine did not reside in the home). Results also revealed the presence of dust mites. Seven percent (7%) of homes tested positive for Der p 1, 19% of homes were positive for Der f 1, and 5% of homes were positive for the Group 2 mite allergens. Indoor relative humidity averaged 27.0 ± 7.6% within the homes. Overall, humidity was not significantly associated with dust mite presence, nor was any of the other measured home characteristics. This study provides a descriptive assessment of indoor allergen presence (including dust mites) in rural areas of the northern Rocky Mountains, and provides new information to assist regional patients with reducing allergen exposure using in-home intervention strategies. PMID:25859563

  16. 77 FR 45715 - Notice of Public Hearing: Reading Blue Mountain and Northern Railroad

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-01

    ... interested parties. See 77 FR 2774-2775 (January 19, 2012). After examining the carrier's proposal and the... Federal Railroad Administration Notice of Public Hearing: Reading Blue Mountain and Northern Railroad The Reading Blue Mountain and Northern Railroad (RBMN) has petitioned the Federal Railroad Administration...

  17. Anthropogenic Mercury Accumulation in Watersheds of the Northern Appalachian Mountains

    NASA Astrophysics Data System (ADS)

    Boyer, E. W.; Drohan, P. J.; Lawler, D.; Grimm, J.; Grant, C.; Eklof, K. J.; Bennett, J.; Naber, M. D.

    2014-12-01

    Atmospheric deposition of mercury (Hg) is a critical environmental stress that affects ecosystems and human health. Mercury emissions to the atmosphere from coal-fired power plants and other sources such as waste incineration can be deposited over large geographic areas to downwind landscapes in precipitation and in dry fallout. The northern Appalachian Mountains are downwind of major atmospheric mercury emissions sources. Some mercury reaches watersheds and streams, where it can accumulate in sediments and biota. Human exposure to mercury occurs primarily through fish consumption, and currently mercury fish eating advisories are in place for many of the streams and lakes in the region. Here, we explored mercury accumulation in forested landscapes - in air, soils, water, and biota. To quantify atmospheric mercury deposition, we measured both wet and dry mercury deposition at 10 forested locations, from which we present variation in mercury deposition and initial assessments of factors affecting the patterns. To quantify mercury accumulation in terrestrial environments, we measured soil mercury concentrations within and surrounding 12 vernal pools spanning various physiographic settings in the region. Given that vernal pools have large inputs of water via precipitation yet do not have any stream discharge outflow, they are likely spots within the forested landscape to accumulate pollutants that enter via wet atmospheric deposition. To quantify mercury accumulation in aquatic environments, we sampled mercury concentrations in streams draining 35 forested watersheds, spanning gradients of atmospheric deposition, climate and geology. Mercury concentrations were measured in stream water under base-flow conditions, in streambed sediments, aquatic mosses, and in fish tissues from brook trout. Results indicate that wet and dry atmospheric deposition is a primary source of mercury that is accumulating in watersheds of the Northern Appalachian Mountains.

  18. Hydrogeologic data for the northern Rocky Mountains intermontane basins, Montana

    USGS Publications Warehouse

    Dutton, DeAnn M.; Lawlor, Sean M.; Briar, D.W.; Tresch, R.E.

    1995-01-01

    The U.S. Geological Survey began a Regional Aquifer- System Analysis of the Northern Rocky Mountains Intermontane Basins of western Montana and central and central and northern Idaho in 1990 to establish a regional framework of information for aquifers in 54 intermontane basins in an area of about 77,500 square miles. Selected hydrogeologic data have been used as part of this analysis to define the hydro- logic systems. Records of 1,376 wells completed in 31 of the 34 intermontane basins in the Montana part of the study area are tabulated in this report. Data consist of location, alttiude of land surface, date well constructed, geologic unit, depth of well, diameter of casing, type of finish, top of open interval, primary use of water, water level, date water level measured, discharge, specific capacity, source of discharge data, type of log available, date water-quality parameters measured, specific conductance, pH, and temperature. Hydrographs for selected wells also are included. Locations of wells and basins are shown on the accompanying plate.

  19. A gravity model of the deep structure of South Caspian Basin along submeridional profile Alborz-Absheron Sill

    NASA Astrophysics Data System (ADS)

    Kadirov, F. A.; Gadirov, A. H.

    2014-03-01

    The South-Caspian Basin (SCB) underlies the southern part of the Caspian Sea, between the ranges of the eastern Greater Caucasus, Talysh, Alborz, and Kopet Dagh. A 2-D regional gravity model along a profile from the Alborz Mountains to the Absheron Ridge has been constructed, constrained by deep (20 s TWT) seismic reflection data. The deep structure model has been evaluated in terms of earthquake focal mechanisms and GPS velocity data to elucidate active tectonic processes and the geodynamic evolution of the SCB. We believe that the rapid increase in the thickness of Mesozoic sediments along the profile from ~ 8 km in the middle part of the profile up to ~ 15 km in the area of the Absheron-Ridge can be explained by inherent basin geometry created by thermal subsidence followed by sediment loading as well as additional effect of tectonic related shortening of sedimentary succession. Near the boundary of oceanic and continental crust in the northern SCB, flexure of oceanic crust is inferred from the observed seismic data and gravity modeling, most probably connected to ongoing subduction of lithosphere of the South Caspian underneath the Scythian Plate of the Mid-Caspian. Subduction beneath the Absheron Ridge is accompanied by the delamination of sediments from the oceanic crust (“basaltic” layer) and creation of accretionary wedge in the overlaying sedimentary succession. The focal mechanisms of the larger earthquakes (M > 6) occurring along the northern boundary of the SCB show steep normal-type faulting above the bend of the downgoing slab while, along the southern boundary, thrust faults are inferred. Some thrust-type earthquakes near the northern boundary occur in the lower crust or uppermost mantle and may be associated with compression in the lower part of the brittle lithosphere due to plate flexure. Displacements measured along the coastline of the Caspian Sea by GPS are consistent with the direction of potential oblique subduction of oceanic crust of

  20. Upper mantle shear wave velocity structure beneath northern Victoria Land, Antarctica: Volcanism and uplift in the northern Transantarctic Mountains

    NASA Astrophysics Data System (ADS)

    Graw, Jordan H.; Adams, Aubreya N.; Hansen, Samantha E.; Wiens, Douglas A.; Hackworth, Lauren; Park, Yongcheol

    2016-09-01

    The Transantarctic Mountains (TAMs) are the largest non-compressional mountain range on Earth, and while a variety of uplift mechanisms have been proposed, the origin of the TAMs is still a matter of great debate. Most previous seismic investigations of the TAMs have focused on a central portion of the mountain range, near Ross Island, providing little along-strike constraint on the upper mantle structure, which is needed to better assess competing uplift models. Using data recorded by the recently deployed Transantarctic Mountains Northern Network, as well as data from the Transantarctic Mountains Seismic Experiment and from five stations operated by the Korea Polar Research Institute, we investigate the upper mantle structure beneath a previously unexplored portion of the mountain range. Rayleigh wave phase velocities are calculated using a two-plane wave approximation and are inverted for shear wave velocity structure. Our model shows a low velocity zone (LVZ; ∼4.24 km s-1) at ∼160 km depth offshore and adjacent to Mt. Melbourne. This LVZ extends inland and vertically upwards, with more lateral coverage above ∼100 km depth beneath the northern TAMs and Victoria Land. A prominent LVZ (∼4.16-4.24 km s-1) also exists at ∼150 km depth beneath Ross Island, which agrees with previous results in the TAMs near the McMurdo Dry Valleys, and relatively slow velocities (∼4.24-4.32 km s-1) along the Terror Rift connect the low velocity anomalies. We propose that the LVZs reflect rift-related decompression melting and provide thermally buoyant support for the TAMs uplift, consistent with proposed flexural models. We also suggest that heating, and hence uplift, along the mountain front is not uniform and that the shallower LVZ beneath northern Victoria Land provides greater thermal support, leading to higher bedrock topography in the northern TAMs. Young (0-15 Ma) volcanic rocks associated with the Hallett and the Erebus Volcanic Provinces are situated directly

  1. National coal resource assessment: Fort Union coals of the Northern Rocky Mountains and Great Plains

    SciTech Connect

    Flores, R.M.; Bader, L.R.; Ellis, M.S. |

    1996-12-31

    The present investigation assesses geologic controls on the distribution, resource occurrence, and quality of the Paleocene Fort Union and equivalent coals in the northern Rocky Mountains and Great Plains. Results of this investigation will assist in predicting areas wit h high quality coals that will be available for development. Published products will include digital output and hard copy readily accessible for analysis and utilization.

  2. Floods at the northern foothills of the Tatra Mountains — A Polish-Swiss research project

    NASA Astrophysics Data System (ADS)

    Kundzewicz, Zbigniew; Stoffel, Markus; Kaczka, Ryszard; Wyżga, Bartłomiej; Niedźwiedź, Tadeusz; Pińskwar, Iwona; Ruiz-Villanueva, Virginia; Łupikasza, Ewa; Czajka, Barbara; Ballesteros-Canovas, Juan; Małarzewski, Łukasz; Choryński, Adam; Janecka, Karolina; Mikuś, Paweł

    2014-06-01

    The present paper introduces the topical area of the Polish-Swiss research project FLORIST (Flood risk on the northern foothills of the Tatra Mountains), informs on its objectives, and reports on initial results. The Tatra Mountains are the area of the highest precipitation in Poland and largely contribute to flood generation. The project is focused around four competence clusters: observation-based climatology, model-based climate change projections and impact assessment, dendrogeomorphology, and impact of large wood debris on fluvial processes. The knowledge generated in the FLORIST project is likely to have impact on understanding and interpretation of flood risk on the northern foothills of the Tatra Mountains, in the past, present, and future. It can help solving important practical problems related to flood risk reduction strategies and flood preparedness.

  3. Quaternary glacial evolution in the Central Cantabrian Mountains (Northern Spain)

    NASA Astrophysics Data System (ADS)

    Serrano, E.; González-Trueba, J. J.; Pellitero, R.; González-García, M.; Gómez-Lende, M.

    2013-08-01

    The glacial evolution of the Cantabrian Mountains is not well known. Previous studies have focused on the extent of the glacial maximum and the presence of younger features in several massifs. Recently, efforts have been made to date glacial periods, particularly the glacial maximum. This work presents a reconstruction of the glacial evolution in the Cantabrian Mountains, providing data on the environmental characteristics and timing of the different stages from the Quaternary glacial maximum to the Little Ice Age. The study area covers 3000 km2 between the 4°58'W and 3°34'W and includes eleven massifs of the central area of the Cantabrian Mountains. The selected sectors have an Atlantic and Atlantic-Mediterranean transitional climate and include the highest massifs (above 2600 m) and low-altitude glacierised massifs (lower than 2000 m). Glacial extent and evolution have been reconstructed on the basis of detailed geomorphological and morphostratigraphic mapping. The equilibrium line altitude (palaeo-ELA) has been estimated for the different stages of each tongue. The ELA has been assessed by the AAR and modified Kurowski methods and altitude methods have been considered. A numerical chronological framework is proposed using 17 AMS radiocarbon and one OSL data obtained in lake and bog deposits from three massifs. Four main glacial stages have been differentiated, between 38,000 BP and the Little Ice Age. They correspond to different cold environments, and the number of glacial stages varies from one to four among the different massifs. Conclusions are analysed in the context of the Quaternary glacial evolution of other Iberian mountains.

  4. Variation of coda wave attenuation in the Alborz region and central Iran

    NASA Astrophysics Data System (ADS)

    Rahimi, H.; Motaghi, K.; Mukhopadhyay, S.; Hamzehloo, H.

    2010-06-01

    More than 340 earthquakes recorded by the Institute of Geophysics, University of Tehran (IGUT) short period stations from 1996 to 2004 were analysed to estimate the S-coda attenuation in the Alborz region, the northern part of the Alpine-Himalayan orogen in western Asia, and in central Iran, which is the foreland of this orogen. The coda quality factor, Qc, was estimated using the single backscattering model in frequency bands of 1-25 Hz. In this research, lateral and depth variation of Qc in the Alborz region and central Iran are studied. It is observed that in the Alborz region there is absence of significant lateral variation in Qc. The average frequency relation for this region is Qc = 79 +/- 2f1.07+/-0.08. Two anomalous high-attenuation areas in central Iran are recognized around the stations LAS and RAZ. The average frequency relation for central Iran excluding the values of these two stations is Qc = 94 +/- 2f0.97+/-0.12. To investigate the attenuation variation with depth, Qc value was calculated for 14 lapse times (25, 30, 35,... 90s) for two data sets having epicentral distance range R < 100 km (data set 1) and 100 < R < 200 km (data set 2) in each area. It is observed that Qc increases with depth. However, the rate of increase of Qc with depth is not uniform in our study area. Beneath central Iran the rate of increase of Qc is greater at depths less than 100 km compared to that at larger depths indicating the existence of a high attenuation anomalous structure under the lithosphere of central Iran. In addition, below ~180 km, the Qc value does not vary much with depth under both study areas, indicating the presence of a transparent mantle under them.

  5. Paleomagnetic contributions to the Klamath Mountains terrane puzzle-a new piece from the Ironside Mountain batholith, northern California

    USGS Publications Warehouse

    Mankinen, Edward A.; Gromme, C. Sherman; Irwin, W. Porter

    2013-01-01

    We obtained paleomagnetic samples from six sites within the Middle Jurassic Ironside Mountain batholith (~170 Ma), which constitutes the structurally lowest part of the Western Hayfork terrane, in the Klamath Mountains province of northern California and southern Oregon. Structural attitudes measured in the coeval Hayfork Bally Meta-andesite were used to correct paleomagnetic data from the batholith. Comparing the corrected paleomagnetic pole with a 170-Ma reference pole for North America indicates 73.5° ± 10.6° of clockwise rotation relative to the craton. Nearly one-half of this rotation may have occurred before the terrane accreted to the composite Klamath province at ~168 Ma. No latitudinal displacement of the batholith was detected.

  6. Paleomagnetism and tectonics of the Crescent Formation, northern Olympic Mountains, Washington

    NASA Technical Reports Server (NTRS)

    Warnock, Andrew C.; Burmester, Russell F.; Engebretson, David C.

    1993-01-01

    Results are presented of a paleomagnetic analysis of the Crescent Formation basalts of the northern Olympic Mountains, carried out with the purpose of constraining the emplacement and deformation history of the rocks of the northern Coast Range. It was found that (1) the stable remanent magnetization measured within the Crescent Formation appears to be early, predating significant deformation, and probably is primary; (2) a correction for bedding rotations about strike within four different structural domains produces a circular distribution of virtual geomagnetic poles; and (3) the Crescent Formation, where sampled in the north, records no significant net rotation or displacement.

  7. The displaced eugeoclinal rocks in the El Paso Mountains and northern Mojave Desert: A Triassic sliver

    SciTech Connect

    Miller, J.S.; Glazner, A.F. . Dept. of Geology); Walker, J.D.; Martin, M.W. . Dept. of Geology)

    1993-04-01

    Many workers have drawn attention to the displaced eugeoclinal rocks in the northern Mojave Desert and El Paso Mountains and their importance in models for the development of an active continental margin in the western Cordillera. Existing models can generally for either strike-slip juxtaposition or thrust emplacement. New field data, U-Pb zircon geochronology, and isotopic data for metasedimentary rocks and plutons in the northern Mojave Desert and El Paso Mountains shed light on the timing and mechanism of emplacement of the eugeoclinal allocthon. The observations and data above indicate that Early Triassic plutons in the northern Mojave Desert came through oceanic lithosphere but later Jurassic plutons intercepted continental lithosphere. The authors suggest a model where eugeoclinal rocks were deposited on oceanic crust which was initially brought southward along a strike-slip fault and later thrust eastward over the cratonal assemblage. Permian thrusting is incompatible with their data and observations. Intrusion of lower Triassic strata by Early Triassic plutons in the Lane Mountain area permits some Early Triassic thrusting but the oceanic affinity of the plutons implies that thrusting did not involve continental lithosphere.

  8. Analyzing Whitebark Pine Distribution in the Northern Rocky Mountains in Support of Grizzly Bear Recovery

    NASA Astrophysics Data System (ADS)

    Lawrence, R.; Landenburger, L.; Jewett, J.

    2007-12-01

    Whitebark pine seeds have long been identified as the most significant vegetative food source for grizzly bears in the Greater Yellowstone Ecosystem (GYE) and, hence, a crucial element of suitable grizzly bear habitat. The overall health and status of whitebark pine in the GYE is currently threatened by mountain pine beetle infestations and the spread of whitepine blister rust. Whitebark pine distribution (presence/absence) was mapped for the GYE using Landsat 7 Enhanced Thematic Mapper (ETM+) imagery and topographic data as part of a long-term inter-agency monitoring program. Logistic regression was compared with classification tree analysis (CTA) with and without boosting. Overall comparative classification accuracies for the central portion of the GYE covering three ETM+ images along a single path ranged from 91.6% using logistic regression to 95.8% with See5's CTA algorithm with the maximum 99 boosts. The analysis is being extended to the entire northern Rocky Mountain Ecosystem and extended over decadal time scales. The analysis is being extended to the entire northern Rocky Mountain Ecosystem and extended over decadal time scales.

  9. Mountains

    SciTech Connect

    Fuller, M.

    1989-01-01

    This book covers the following topics: Above the forest: the alpine tundra; Solar energy, water, wind and soil in mountains; Mountain weather; Mountain building and plate tectonics; Mountain walls: forming, changing, and disappearing; Living high: mountain ecosystems; Distribution of mountain plants and animals; On foot in the mountains: how to hike and backpack; Ranges and peaks of the world. Map and guidebook sources, natural history and mountain adventure trips, mountain environmental education centers and programs, and sources of information on trails for the handicapped are included.

  10. Landscape Evolution Changes Along the Western Andean Mountain Front of Peru and Northern Chile

    NASA Astrophysics Data System (ADS)

    Hoke, G. D.; Isacks, B. L.; Jordan, T. E.

    2003-12-01

    We describe the along-strike changes in geomorphology on the western Andean mountain front of Peru and northern Chile, using the newly released SRTM 90 m digital topography. Strong contrasts in drainage systems and slope distributions occur along the mountain front between Lima, Peru and Santiago, Chile in concert with major latitudinal changes in climate. The climatic gradients appear to have been approximately stable since the middle Miocene. We link morphologies observed in satellite images, topography, topographically derived slope, and river networks to along-strike variations in erosional processes occurring along the climate gradient. The areas characterized below include: 1) between 12-15° S, a zone where landforms suggest the important role of local precipitation, 2) from 15-18° S the landforms are indicative of no significant local precipitation but significant stream power from upland regions, 3) from 18-25° S there is neither local precipitation nor appreciable stream power and 4) between 25-32° S where the influence of the westerly air masses gradually increases the amount of local precipitation falling on the western mountain front. Near Lima, on the western coast of Peru, the landscape is actively eroding with high median values of slope and well-developed drainage systems. We interpret this to signify that precipitation is delivered directly on the mountain front. The western mountain front of southwestern Peru contains possibly the greatest relief on earth. There, we see a bimodal slope distribution highlighting the steep slopes of the canyon networks and the low slopes of the smooth, low relief interfluve areas. The interfluves are little eroded geomorphic surfaces suggesting that precipitation rarely falls on the mountain front and that most of the water required to cut the deep canyons are derived from snow melt on the high elevations in the northernmost Altiplano. Channel profiles of the deeper canyons in this sector show that, relative to

  11. Younger Dryas glaciation and climate in the Mourne Mountains, Northern Ireland

    NASA Astrophysics Data System (ADS)

    Barr, Iestyn; Devaney, Maia; Flood, Rory; Roberson, Sam

    2016-04-01

    Here we investigate glaciation and climate in the Mourne Mountains, Northern Ireland, during the Younger Dryas (YD; c. 12.9-11.7 ka BP), using a combination of field-mapping, remote sensing and glacier mass balance modelling. Results indicate that small, independent (likely snow-field fed) glaciers occupied the mountains during this period, with Equilibrium Line Altitudes (ELAs) ranging from ~ 450 to 708 m above sea level. Based on these estimates, mass balance modelling suggest a ~ 8°C reduction in mean annual temperature at the YD (assuming precipitation values comparable to present). Despite this, though the chronology and style of glacial retreat from the Last Glacial Maximum would suggest that the reconstructed glaciers relate to the YD, new radiocarbon dating of basal contact organics (conducted as part of this investigation) has been unable to conclusively verify a YD age.

  12. Crustal structure beneath the Northern Transantarctic Mountains and Wilkes Subglacial Basin: Implications for tectonic origins

    NASA Astrophysics Data System (ADS)

    Hansen, Samantha E.; Kenyon, Lindsey M.; Graw, Jordan H.; Park, Yongcheol; Nyblade, Andrew A.

    2016-02-01

    The Transantarctic Mountains (TAMs) are the largest noncollisional mountain range on Earth. Their origin, as well as the origin of the Wilkes Subglacial Basin (WSB) along the inland side of the TAMs, has been widely debated, and a key constraint to distinguish between competing models is the underlying crustal structure. Previous investigations have examined this structure but have primarily focused on a small region of the central TAMs near Ross Island, providing little along-strike constraint. In this study, we use data from the new Transantarctic Mountains Northern Network and from five stations operated by the Korea Polar Research Institute to investigate the crustal structure beneath a previously unexplored portion of the TAMs. Using S wave receiver functions and Rayleigh wave phase velocities, crustal thickness and average crustal shear velocity (V>¯s) are resolved within ±4 km and ±0.1 km/s, respectively. The crust thickens from ~20 km near the Ross Sea coast to ~46 km beneath the northern TAMs, which is somewhat thicker than that imaged in previous studies beneath the central TAMs. The crust thins to ~41 km beneath the WSB. V>¯s ranges from ~3.1-3.9 km/s, with slower velocities near the coast. Our findings are consistent with a flexural origin for the TAMs and WSB, where these features result from broad flexure of the East Antarctic lithosphere and uplift along its western edge due to thermal conduction from hotter mantle beneath West Antarctica. Locally, thicker crust may explain the ~1 km of additional topography in the northern TAMs compared to the central TAMs.

  13. Optical Observations of Lightning in Northern India Himalayan Mountain Countries and Tibet

    NASA Technical Reports Server (NTRS)

    Boeck, William L.; Mach, D. M.; Goodman, S. J.; Christian, Hugh J., Jr.

    1999-01-01

    This study summarizes the results of an analysis of data from the LIS instrument on the TRMM platform. The data for the Indian summer monsoon season is examined to study the seasonal patterns of the geographic and diurnal distribution of lightning storms. The storms on the Tibetan plateau show a single large diurnal peak at about 1400 local solar time. A region of Northern Pakistan has two storm peaks at 0200 and 1400 local solar time. The morning peak is half the magnitude of the afternoon peak. The region south of the Himalayan Mountains has a combined diurnal cycle in location and time of storm occurrence.

  14. Optical Observations of Lightning in Northern India, Himalayan Mountain Countries and Tibet

    NASA Technical Reports Server (NTRS)

    Boeck, W. L.; Mach, D.; Goodman, S. J.; Christian, H. J., Jr.

    1999-01-01

    This study summarizes the results of an analysis of data from the LIS instrument on the TRMM platform. The data for the Indian summer monsoon season is examined to study the seasonal patterns of the geographic and diurnal distribution of lightning storms. The storms on the Tibetan plateau show a single large diurnal peak at about 1400 local solar time. A region of Northern Pakistan has two storm peaks at 0200 and 1400 local solar time. The morning peak is half the magnitude of the afternoon peak. The region south of the Himalayan Mountains has a combined diurnal cycle in location and time of storm occurrence.

  15. Quaternary glacial landforms and evolution in the Cantabrian Mountains (Northern Spain): a synthesis from current data

    NASA Astrophysics Data System (ADS)

    Serrano, Enrique; José González-Trueba, Juan; Pellitero, Ramón; González-García, María; Gómez-Lende, Manuel

    2014-05-01

    In Northern Iberian Peninsula are located the Cantabrian Mountains, a mountain system of 450 km length, reaching 2648 m in the Picos de Europa. It is an Atlantic mountain in the North slope, with a Atlantic Mediterranean transitional climate in the South slope.More than thirty-five massifs developed glaciers during the Pleistocene. Studies on glacial morphology are known from the XIX century and they have focused mainly on the maximum extent of glaciers. Nowadays there are detailed geomorphological maps, morphostratigraphic surveys and estimation of Equilibrium Line Altitude in different massifs and on different stages. During the last decade studies on glacial evolution and glaciation phases have been made, and the first chronological data have been published. In this work we presents the reconstruction of the glacial evolution in the Cantabrian Mountains during the Pleistocene and Holocene, based on recent chronological data (30 dates made using OSL, AMS and C14) and morphostratigraphic correlations obtained by several research groups. The number of reconstructed glacial stages varies among the different massifs, form one to four different stages. The highest massifs located in the central portion of the Cantabrian Mountains have the most complex glacial features, with at least four different moraine complexes stepped between the 400 m a.s.l in the Northern slope and 800 m a.s.l. in the Southern slope for the lowest moraine complexes, and the highest and youngest, located above 2100 m a.s.l. An ancient glacial phase has been pointed to MIS 12 -more than 400 ka-, disconnected from the present day glacial morphology. During Upper Pleistocene three main stages have been identified. The first one, the local glacial maximum, could be prior to the LGM, as all dates refer to chronologies prior to 28-38 ka. Some authors locate this stage prior to 45 and 65 ka, during the 50-70 ka cold stage. It could be a wet stage, when the main fronts reached the Iberian Peninsula from

  16. Reconstruction and analysis of the past five centuries of streamflow on northern slopes on Tianshan Mountains in Northern Xinjiang, China

    NASA Astrophysics Data System (ADS)

    Yang, Yuhui; Chen, Yaning; Wang, Minzhong; Sun, Huilan

    2016-03-01

    We examined the changes in streamflow on the northern slopes of the Tianshan Mountains in northern Xinjiang, China, over two time scales: the past 500 years, based on dendrochronology data; and the past 50 years, based on streamflow data from hydrological stations. The method of artificial neural networks built from the data of the 50-year period was used to reconstruct the streamflow of the 500-year period. The results indicate that streamflow has undergone seven high-flow periods and four low-flow periods during the past 500 years. To identify possible transition points in the streamflow, we applied the Mann-Kendall and running T tests to the 50- and 500-year periods, respectively. During the past 500 years, streamflow has changed significantly from low to high flow about three to four times, and from high to low flow about three to five times. Over the recent 50 years, there have been three phases of variation in river runoff, and the most distinct transition of streamflow occurred in 1996.

  17. Relational Database for the Geology of the Northern Rocky Mountains - Idaho, Montana, and Washington

    USGS Publications Warehouse

    Causey, J. Douglas; Zientek, Michael L.; Bookstrom, Arthur A.; Frost, Thomas P.; Evans, Karl V.; Wilson, Anna B.; Van Gosen, Bradley S.; Boleneus, David E.; Pitts, Rebecca A.

    2008-01-01

    A relational database was created to prepare and organize geologic map-unit and lithologic descriptions for input into a spatial database for the geology of the northern Rocky Mountains, a compilation of forty-three geologic maps for parts of Idaho, Montana, and Washington in U.S. Geological Survey Open File Report 2005-1235. Not all of the information was transferred to and incorporated in the spatial database due to physical file limitations. This report releases that part of the relational database that was completed for that earlier product. In addition to descriptive geologic information for the northern Rocky Mountains region, the relational database contains a substantial bibliography of geologic literature for the area. The relational database nrgeo.mdb (linked below) is available in Microsoft Access version 2000, a proprietary database program. The relational database contains data tables and other tables used to define terms, relationships between the data tables, and hierarchical relationships in the data; forms used to enter data; and queries used to extract data.

  18. The Rudbār Mw 7.3 earthquake of 1990 June 20; seismotectonics, coseismic and geomorphic displacements, and historic earthquakes of the western `High-Alborz', Iran

    NASA Astrophysics Data System (ADS)

    Berberian, Manuel; Walker, Richard

    2010-09-01

    The Rudbār earthquake of 1990 June 20, the first large-magnitude earthquake with 80 km left-lateral strike-slip motion in the western `High-Alborz' fold-thrust mountain belt, was one of the largest, and most destructive, earthquakes to have occurred in Iran during the instrumental period. We bring together new and existing data on macroseismic effects, the rupture characteristics of the mainshock, field data, and the distribution of aftershocks, to provide a better description of the earthquake source, its surface ruptures, and active tectonic characteristics of the western `High-Alborz'. The Rudbār earthquake is one of three large magnitude events to have occurred in this part of the Alborz during recorded history. The damage distribution of the 1485 August 15 Upper Polrud earthquake suggests the east-west Kelishom left-lateral fault, which is situated east of the Rudbār earthquake fault, as a possible source. The 1608 April 20 Alamutrud earthquake may have occurred on the Alamutrud fault farther east. Analysis of satellite imagery suggests that total left-lateral displacements on the Rudbār fault are a maximum of ~1 km. Apparent left-lateral river displacements of ~200 m on the Kashachāl fault and up to ~1.5 km of the Kelishom fault, which are situated at the eastern end of the Rudbār earthquake fault, also appear to indicate rather small cumulative displacements. Given the relatively small displacements, the presently active left-lateral strike-slip faults of the western High-Alborz fold-thrust belt, may be younger than onset of deformation within the Alborz Mountains as a whole.

  19. Arsenic in groundwaters in the Northern Appalachian Mountain belt: A review of patterns and processes

    NASA Astrophysics Data System (ADS)

    Peters, Stephen C.

    2008-07-01

    Naturally occurring arsenic in the bedrock of the Northern Appalachian Mountain belt was first recognized in the late 19th century. The knowledge of the behavior of arsenic in groundwater in this region has lagged behind nearly a century, with the popular press reporting on local studies in the early 1980s, and most peer-reviewed research articles on regional patterns conducted and written in the late 1990s and early 2000s. Research reports have shown that within this high arsenic region, between 6% and 22% of households using private drinking water wells contain arsenic in excess of 10 µg/L, the United States Environmental Protection Agency's maximum contaminant level. In nearly all reports, arsenic in drinking water was derived from naturally occurring geologic sources, typically arsenopyrite, substituted sulfides such as arsenian pyrite, and nanoscale minerals such as westerveldite. In most studies, arsenic concentrations in groundwater were controlled by pH dependent adsorption to mineral surfaces, most commonly iron oxide minerals. In some cases, reductive dissolution of iron minerals has been shown to increase arsenic concentrations in groundwater, more commonly associated with anthropogenic activities such as landfills. Evidence of nitrate reduction promoting the presence of arsenic(V) and iron(III) minerals in anoxic environments has been shown to occur in surface waters, and in this manuscript we show this process perhaps applies to groundwater. The geologic explanation for the high arsenic region in the Northern Appalachian Mountain belt is most likely the crustal recycling of arsenic as an incompatible element during tectonic activity. Accretion of multiple terranes, in particular Avalonia and the Central Maine Terrane of New England appear to be connected to the presence of high concentrations of arsenic. Continued tectonic activity and recycling of these older terranes may also be responsible for the high arsenic observed in the Triassic rift basins

  20. Winter feeding habits of the mountain bluebird (Sialia currucoides) in northern New Mexico

    SciTech Connect

    Burnett, Kassidy; Fair, Jeanne M

    2008-01-01

    The Mountain Bluebird (Sialia currucoides) is found in western North America and is known for the blue color that completely covers the male (Martin et al. 1951). The Mountain Bluebird habitat spans through the Rocky Mountains as well as the Sierra Cascade regions, but winters in the milder parts of this geographic area which includes New Mexico (Martin, et al. 1951). However, Mountain Bluebirds in New Mexico are often permanent residents as well (unpublished data). During the summer breeding months, the Mountain Bluebird consumes 92% of its diet in insects as well as other animal matter (Bent, 1942). However, little is known about the diet of Mountain Bluebirds in the winter. From December 2004 through February 2005, approximately 40 Mountain Bluebirds flocked together in Nambe, New Mexico. The arroyo habitat includes One-seed Juniper (Juniperus monosperma), Silver Sagebrush (Artemisia cana), and sparse Narrowleaf Cottonwood (Populus angustifolia). Our focus was to analyze the winter feeding habits of the Mountain Bluebird in the northern area of New Mexico. We collected a total of 115.97 grams Mountain Bluebirds droppings from the pond in the study area. We sorted through the droppings to distinguish between different food types consumed, and found that the winter diet consisted primarily of fruit seeds. This is supported by Martin et al. (1951) who states that fruits constitute most of the small proportion of plant material in the diet of the Mountain Bluebird. Power and Lombardo (1996) who determined from stomach contents obtained over an entire period of a year the Mountain Bluebird diet consist of grapes, currants, elderberries, sumac seeds, mistletoe seeds, and hackberry seeds. The main fruit found was that of the One-Seed Juniper which weighed 105.7 grams (91.2% of material collected). The One-Seed Juniper is one of five of juniper species found in Northern New Mexico (Foxx and Hoard 1995). The One-Seed Juniper can be found in the southwestern United States

  1. A new subspecies of Seseli gummiferum (Apiaceae) from Ilgaz Mountain National Park, northern Turkey

    PubMed Central

    Çetin, Özlem; Şeker, Meryem Öztürk; Duran, Ahmet

    2015-01-01

    Abstract A new subspecies Seseli gummiferum Pall. ex Sm. subsp. ilgazense A.Duran, Ö.Çetin & M.Öztürk, subsp. nov. (Apiaceae) is described from Kastamonu province, Turkey. It was collected from the open Pinus sylvestris L. and Abies nordmanniana (Steven) É.Spach. mixed forest in the northern Anatolian region. An endemic apparently confined to the Ilgaz Mountain National Park, the new taxon is closely related to Seseli gummiferum subsp. gummiferum. Diagnostic morphological characters for closely similar taxa are discussed, and a key to the subspecies of Seseli gummiferum is presented. ITS (Internal Transcribed Spacer) region of the nuclear ribozomal DNA of closely related Seseli L. taxa and Pimpinella is used to constract phylogenetic tree by using BioEdit and Seaview Programme. PMID:26491389

  2. Geology and depositional environments of the Guadalupian rocks of the northern Del Norte Mountains, West Texas

    USGS Publications Warehouse

    Rudine, S.F.; Wardlaw, B.R.; Rohr, D.M.; Grant, R.E.

    2000-01-01

    The Guadalupian rocks of the northern Del Norte Mountains were deposited in a foreland basin between land of the Marathon orogen and a carbonate shoal established on the geanticline separating the foreland basin from the Delaware basin. Deposition was alternately influenced by coarse clastic input from the orogen and carbonate shoal, which interrupted shallow basinal siltstone depletion. Relatively deeper-water deposition is characterized by carbonate input from the shoal, and relatively shallow-water deposition is characterized by sandstone input from the orogen. Deposition was in five general transgressive-regressive packages that include (1) the Road Canyon Formation and the first siltstone member and first sandstone member of the Word Formation, (2) the second siltstone member, Appel Ranch Member, and limy sandy siltstone member of the Word Formation, (3) the Vidrio Formation, (4) the lower and part of the middle members of the Altuda Formation, and (5) part of the middle and upper members of the Altuda Formation.

  3. A new subspecies of Seseli gummiferum (Apiaceae) from Ilgaz Mountain National Park, northern Turkey.

    PubMed

    Çetin, Özlem; Şeker, Meryem Öztürk; Duran, Ahmet

    2015-01-01

    A new subspecies Seseli gummiferum Pall. ex Sm. subsp. ilgazense A.Duran, Ö.Çetin & M.Öztürk, subsp. nov. (Apiaceae) is described from Kastamonu province, Turkey. It was collected from the open Pinus sylvestris L. and Abies nordmanniana (Steven) É.Spach. mixed forest in the northern Anatolian region. An endemic apparently confined to the Ilgaz Mountain National Park, the new taxon is closely related to Seseli gummiferum subsp. gummiferum. Diagnostic morphological characters for closely similar taxa are discussed, and a key to the subspecies of Seseli gummiferum is presented. ITS (Internal Transcribed Spacer) region of the nuclear ribozomal DNA of closely related Seseli L. taxa and Pimpinella is used to constract phylogenetic tree by using BioEdit and Seaview Programme. PMID:26491389

  4. Ground-water levels in intermontane basins of the northern Rocky Mountains, Montana and Idaho

    USGS Publications Warehouse

    Briar, David W.; Lawlor, S.M.; Stone, M.A.; Parliman, D.J.; Schaefer, J.L.; Kendy, Eloise

    1996-01-01

    The Regional Aquifer-System Analysis (RASA) program is a series of studies by the U.S. Geological Survey (USGS) to analyze regional ground-water systems that compose a major portion of the Nation's water supply (Sun, 1986). The Northern Rocky Mountains Intermontane Basins is one of the study regions in this national program. The main objectives of the RASA studies are to (1) describe the groundwater systems as they exist today, (2) analyze the known changes that have led to the systems present condition, (3) combine results of previous studies in a regional analysis, where possible, and (4) provide means by which effects of future ground-water development can be estimated.The purpose of this study, which began in 1990, was to increase understanding of the hydrogeology of the intermontane basins of the Northern Rocky Mountains area. This report is Chapter B of a three-part series and shows the general distribution of ground-water levels in basin-fill deposits in the study area. Chapter A (Tuck and others, 1996) describes the geologic history and generalized hydrogeologic units. Chapter C (Clark and Dutton, 1996) describes the quality of ground and surface waters in the study area.Ground-water levels shown in this report were measured primarily during summer 1991 and summer 1992; however, historical water levels were used for areas where more recent data could not be obtained. The information provided allows for the evaluation of general directions of ground-water flow, identification of recharge and discharge areas, and determination of hydraulic gradients within basin-fill deposits.

  5. Ash-flow tuffs of the Galiuro Volcanics in the northern Galiuro Mountains, Pinal County, Arizona

    USGS Publications Warehouse

    Krieger, Medora Louise Hooper

    1979-01-01

    The upper Oligocene and lower Miocene Galiuro Volcanics in the northern part of the Galiuro Mountains contains two distinctive major ash-flow tuff sheets, the Holy Joe and Aravaipa Members. These major ash-flows illustrate many features of ash-flow geology not generally exposed so completely. The Holy Joe Member, composed of a series of densely welded flows of quartz latite composition that make up a simple cooling unit. is a rare example of a cooling unit that has a vitrophyre at the top as well as at the base. The upper vitrophyre does not represent a cooling break. The Aravaipa Member. a rhyolite, is completely exposed in Aravaipa and other canyons and on Table Mountain. Remarkable exposures along Whitewash Canyon exhibit the complete change from a typical stacked-up interior zonation of an ash flow to a non welded distal margin. Vertical and horizontal changes in welding, crystallization, specific gravity, and lithology are exposed. The ash flow can be divided into six lithologic zones. The Holy Joe and Aravaipa Members of the Galiuro Volcanics are so well exposed and so clearly show characteristic features of ash-flow tuffs that they could be a valuable teaching aid and a source of theses for geology students.

  6. Holocene forest development and maintenance on different substrates in the Klamath Mountains, northern California, USA.

    PubMed

    Briles, Christy E; Whitlock, Cathy; Skinner, Carl N; Mohr, Jerry

    2011-03-01

    The influence of substrate on long-term vegetation dynamics has received little attention, and yet nutrient-limited ecosystems have some of the highest levels of endemism in the world. The diverse geology of the Klamath Mountains of northern California (USA) allows examination of the long-term influence of edaphic constraints in subalpine forests through a comparison of vegetation histories between nutrient-limited ultramafic substrates and terrain that is more fertile. Pollen and charcoal records spanning up to 15000 years from ultramafic settings reveal a distinctly different vegetation history compared to other soil types. In non-ultramafic settings, the dominant trees and shrubs shifted in elevation in response to Holocene climate variations resulting in compositional and structural changes, whereas on ultramafic substrates changes were primarily structural, not compositional. Fire activity was similar through most of the Holocene with the exception of declines over the last 4000 years on ultramafic substrates, likely due to the reduction of understory fuels and cooler wetter conditions than in the middle Holocene. These results suggest that the tree and shrub distributions were more responsive to past climate changes on non-ultramafic substrates compared to those on ultramafic substrates. The combination of these dynamics may help explain high levels of plant diversity in the Klamath Mountains and provide insights for managing these complex ecosystems. PMID:21608468

  7. Recent mountain pine beetle outbreaks, wildfire severity, and postfire tree regeneration in the US Northern Rockies

    PubMed Central

    Harvey, Brian J.; Donato, Daniel C.; Turner, Monica G.

    2014-01-01

    Widespread tree mortality caused by outbreaks of native bark beetles (Circulionidae: Scolytinae) in recent decades has raised concern among scientists and forest managers about whether beetle outbreaks fuel more ecologically severe forest fires and impair postfire resilience. To investigate this question, we collected extensive field data following multiple fires that burned subalpine forests in 2011 throughout the Northern Rocky Mountains across a spectrum of prefire beetle outbreak severity, primarily from mountain pine beetle (Dendroctonus ponderosae). We found that recent (2001–2010) beetle outbreak severity was unrelated to most field measures of subsequent fire severity, which was instead driven primarily by extreme burning conditions (weather) and topography. In the red stage (0–2 y following beetle outbreak), fire severity was largely unaffected by prefire outbreak severity with few effects detected only under extreme burning conditions. In the gray stage (3–10 y following beetle outbreak), fire severity was largely unaffected by prefire outbreak severity under moderate conditions, but several measures related to surface fire severity increased with outbreak severity under extreme conditions. Initial postfire tree regeneration of the primary beetle host tree [lodgepole pine (Pinus contorta var. latifolia)] was not directly affected by prefire outbreak severity but was instead driven by the presence of a canopy seedbank and by fire severity. Recent beetle outbreaks in subalpine forests affected few measures of wildfire severity and did not hinder the ability of lodgepole pine forests to regenerate after fire, suggesting that resilience in subalpine forests is not necessarily impaired by recent mountain pine beetle outbreaks. PMID:25267633

  8. Climatic controls on the snowmelt hydrology of the northern Rocky Mountains

    USGS Publications Warehouse

    Pederson, G.T.; Gray, S.T.; Ault, T.; Marsh, W.; Fagre, D.B.; Bunn, A.G.; Woodhouse, C.A.; Graumlich, L.J.

    2011-01-01

    The northern Rocky Mountains (NRMs) are a critical headwaters region with the majority of water resources originating from mountain snowpack. Observations showing declines in western U.S. snowpack have implications for water resources and biophysical processes in high-mountain environments. This study investigates oceanic and atmospheric controls underlying changes in timing, variability, and trends documented across the entire hydroclimatic-monitoring system within critical NRM watersheds. Analyses were conducted using records from 25 snow telemetry (SNOTEL) stations, 148 1 April snow course records, stream gauge records from 14 relatively unimpaired rivers, and 37 valley meteorological stations. Over the past four decades, midelevation SNOTEL records show a tendency toward decreased snowpack with peak snow water equivalent (SWE) arriving and melting out earlier. Temperature records show significant seasonal and annual decreases in the number of frost days (days ???0??C) and changes in spring minimum temperatures that correspond with atmospheric circulation changes and surface-albedo feedbacks in March and April. Warmer spring temperatures coupled with increases in mean and variance of spring precipitation correspond strongly to earlier snowmeltout, an increased number of snow-free days, and observed changes in streamflow timing and discharge. The majority of the variability in peak and total annual snowpack and streamflow, however, is explained by season-dependent interannual-to-interdecadal changes in atmospheric circulation associated with Pacific Ocean sea surface temperatures. Over recent decades, increased spring precipitation appears to be buffering NRM total annual streamflow from what would otherwise be greater snow-related declines in hydrologic yield. Results have important implications for ecosystems, water resources, and long-lead-forecasting capabilities. ?? 2011 American Meteorological Society.

  9. Recent mountain pine beetle outbreaks, wildfire severity, and postfire tree regeneration in the US Northern Rockies.

    PubMed

    Harvey, Brian J; Donato, Daniel C; Turner, Monica G

    2014-10-21

    Widespread tree mortality caused by outbreaks of native bark beetles (Circulionidae: Scolytinae) in recent decades has raised concern among scientists and forest managers about whether beetle outbreaks fuel more ecologically severe forest fires and impair postfire resilience. To investigate this question, we collected extensive field data following multiple fires that burned subalpine forests in 2011 throughout the Northern Rocky Mountains across a spectrum of prefire beetle outbreak severity, primarily from mountain pine beetle (Dendroctonus ponderosae). We found that recent (2001-2010) beetle outbreak severity was unrelated to most field measures of subsequent fire severity, which was instead driven primarily by extreme burning conditions (weather) and topography. In the red stage (0-2 y following beetle outbreak), fire severity was largely unaffected by prefire outbreak severity with few effects detected only under extreme burning conditions. In the gray stage (3-10 y following beetle outbreak), fire severity was largely unaffected by prefire outbreak severity under moderate conditions, but several measures related to surface fire severity increased with outbreak severity under extreme conditions. Initial postfire tree regeneration of the primary beetle host tree [lodgepole pine (Pinus contorta var. latifolia)] was not directly affected by prefire outbreak severity but was instead driven by the presence of a canopy seedbank and by fire severity. Recent beetle outbreaks in subalpine forests affected few measures of wildfire severity and did not hinder the ability of lodgepole pine forests to regenerate after fire, suggesting that resilience in subalpine forests is not necessarily impaired by recent mountain pine beetle outbreaks. PMID:25267633

  10. Hydrology of area 54, Northern Great Plains, and Rocky Mountain coal provinces, Colorado and Wyoming

    USGS Publications Warehouse

    Kuhn, Gerhard; Daddow, P.D.; Craig, G.S.; and others

    1983-01-01

    A nationwide need for information characterizing hydrologic conditions in mined and potential mine areas has become paramount with the enactment of the Surface Mining Control and Reclamation Act of 1977. This report, one in a series covering the coal provinces nationwide, presents information thematically by describing single hydrologic topics through the use of brief texts and accompanying maps, graphs, or other illustrations. The summation of the topical discussions provides a description of the hydrology of the area. Area 54, in north-central Colorado and south-central Wyoming, is 1 of 20 hydrologic reporting areas of the Northern Great Plains and Rocky Mountain coal provinces. Part of the Southern Rocky Mountains and Wyoming Basin physiographic provinces, the 8,380-square-mile area is one of contrasting geology, topography, and climate. This results in contrasting hydrologic characteristics. The major streams, the North Platte, Laramie, and Medicine Bow Rivers, and their principal tributaries, all head in granitic mountains and flow into and through sedimentary basins between the mountain ranges. Relief averages 2,000 to 3,000 feet. Precipitation in the mountains may exceed 40 inches annually, much of it during the winter, which produces deep snowpacks. Snowmelt in spring and summer provides most streamflow. Precipitation in the basins averages 10 to 16 inches annually, insufficient for sustained streamflow; thus, streams originating in the basins are ephemeral. Streamflow quality is best in the mountains where dissolved-solids concentrations generally are least. These concentrations increase as streams flow through sedimentary basins. The increases are mainly natural, but some may be due to irrigation in and adjacent to the flood plains. In the North Platte River, dissolved-solids concentrations are usually less than 300 milligrams per liter; in the Laramie and the Medicine Bow Rivers, the concentrations may average 500 to 850 milligrams per liter. However

  11. Establishment of Ulmus pumila seedlings on steppe slopes of the northern Mongolian mountain taiga

    NASA Astrophysics Data System (ADS)

    Dulamsuren, Choimaa; Hauck, Markus; Nyambayar, Suran; Osokhjargal, Dalaikhuu; Leuschner, Christoph

    2009-09-01

    The potential of Siberian elm ( Ulmus pumila) to regenerate from seeds was experimentally studied on south-facing slopes in the northern Mongolian mountain taiga. These slopes are covered with a vegetation mosaic of different steppe communities and small, savanna-like, U. pumila open woodlands. The hypothesis is tested that the xeric microclimate and high herbivore densities limit the success of seedling establishment in U. pumila and thereby prevent elm from complete encroachment of the grassland-dominated slopes. Seeds were sown and 2-yr-old seedlings were planted prior to the growing season. The water supply was manipulated by irrigation, as was the feeding pressure by caterpillars with an insecticide. Large herbivores were excluded by fencing. Seeds germinated throughout the summer, but the emerged seedlings did not survive for more than 2 or 3 weeks. Germination rates increased with increasing soil water content and decreasing soil temperatures. Many seeds were consumed by granivores. Most planted 2-yr-old seedlings survived the two growing seasons covered by the study. However, the seedlings suffered from feeding damage by insects (gypsy moth, grasshoppers) and small mammals, from nitrogen deficiency and, to a lesser degree, from drought. The results suggest that high susceptibility of newly emerged seedlings to environmental stresses is a serious bottle neck for U. pumila that prevents them from the formation of closed forests on northern Mongolia's steppe slopes, whereas the probability for seedling survival after this early stage is high.

  12. Clinoptilolite zeolitized tuff from Central Alborz Range, North Iran

    NASA Astrophysics Data System (ADS)

    Taghipour, Batoul

    2010-05-01

    Zeolites are hydrated alumino-silicates of the alkaline and alkaline earth cations, principally sodium, potassium, calcium, and magnesium (Iijima 1980; Hay 1981). Zeolites occur principally in unmetamorphosed sedimentary rocks and are particularly widespread in volcani-clastic strata (Hay, 1978). Clinoptilolite is a natural zeolite of the heulandite group with the simplified formula of (Na, K)6 Si30 Al6 O72 .nH2. It is the most common natural zeolite found mainly in sedimentary rocks of volcanic origin. Alborz zone is one of the important geological divisions in Iran. This zone is restricted to Kopeh dagh zone in North & Central Iranian zone in South and is a region of active deformation within the broad Arabian-Eurasia collision zone (Allen et al. 2003). The zeolitized green tuff belt from Central Alborz which introduce here are made of volcanoclastic sequence of Karaj Formation. This belt is about 40 km long along Alborz Range and is Eocene in age. Zeolites and associated minerals of this altered vitric tuff studied. Zeolitization took place in some beds of Karaj Formations, with average range of 3 to 300 meters thickness. There are several gypsum lenses which interbed with a widespread green tuff succession in the studied area. On the basis of chemical composition these tuffs are in the range of acid to intermediate volcanic rocks. Also magmatic affinity is calc-alkaline and geological setting of the area belongs to volcanic arc granitoid. Petrographic data has shown that various shape and size of shard glass are the main component of tuffs. Based on the field studies, detail microscopy, XRD and electron microprobe analysis (EMPA), the following main minerals are determined: Clinoptilolite+montmorillonite+crystobalite. Clinoptilolite and smectite are predominant minerals in all altered samples. Concerning the Si/Al ratio of 40 point analyses of glass shards the Alborz tuff has clinoptilolite composition. Otherwise the chemical composition of altered shard glass

  13. The upper Pleistocene on the northern face of the Guadarrama Mountains (central Spain): Palaeoclimatic phases and glacial activity

    NASA Astrophysics Data System (ADS)

    Bullón, Teresa

    2016-09-01

    The present paper provides new information on Pleistocene glacial activity in a mountainous area of the Iberian Central System. A sediment analysis associated with Pleistocene modelling was carried out using: (1) granulometric and morphometric procedures, (2) quartz grain microtexture techniques (SEM) to discriminate between glacial and no glacial origins of sediments, (3) clay X-ray diffraction study to determine intra-Pleistocene climate variability, and (4) optically stimulated luminescence (OSL) absolute dating. The results show that the sediments were formed in two different phases associated with glacial dynamics, one of them was 35-30 ky BP and another was 25-20 ky BP, separated by a short intermediate warm-wet period. Identification of glacial phenomena is new for the northern slopes of the Guadarrama Mountains (facing the north Meseta, Duero basin), although they are not unusual within the general context of the Iberian Central System. From the data provided, we deduce that glaciation in these mountains was much more intense and widespread than had previously been thought because, on the northern slopes, glaciers occupied large areas reaching the base of the mountains. The evidence favours new interpretations of Pleistocene morphology in the centre of the Iberian Peninsula and, by extension, on the southwestern edge of Europe; it also highlights the sensitivity of mountainous areas with regard to Quaternary climate changes.

  14. Geochemical and grain-size evidence for the provenance of loess deposits in the Central Shandong Mountains region, northern China

    NASA Astrophysics Data System (ADS)

    Peng, Shuzhen; Hao, Qingzhen; Wang, Luo; Ding, Min; Zhang, Wei; Wang, Yanan; Guo, Zhengtang

    2016-03-01

    Widespread loess deposits in the Central Shandong Mountains yield valuable paleoclimatic records for this currently semi-humid monsoonal region of northern China. The grain-size distribution and major element composition for bulk samples and two grain-size fractions (< 20 and 20-63 μm) for the loess in the Central Shandong Mountains were compared with loess from the Chinese Loess Plateau and sediment from the Yellow River to help determine its provenance. The presence of a significant percentage of medium- and coarse-silt, and the difference in relatively immobile major element ratios of TiO2/Al2O3 and K2O/Al2O3 for the < 20 and 20-63 μm fractions, suggests that sediment that forms the loess deposits in the Central Shandong Mountains was not blown directly from the northern deserts of China as is the case for the loess deposits of the Chinese Loess Plateau. Rather, this suggests that sediments exposed during glacial times on the North China fluvial plain, including the floodplain of the Yellow River, were the major dust source for the loess in the Central Shangong Mountains. In addition, the wide distribution of perimontane loess in the Central Shandong Mountains region indicates the occurrence of strengthened local aridification during glacial times since the middle Pleistocene.

  15. Updated Long Term Fault Slip Rates and Seismic Hazard in the Central Alborz, Iran: New Constraints From InSAR and GPS

    NASA Astrophysics Data System (ADS)

    Weston, J. M.; Shirzaei, M.

    2015-12-01

    The Alborz mountain range, located south of the Caspian Sea, accommodates 30% of the 25 mm/yr convergence between Arabia and Eurasia. The resulting shortening and left lateral motion is distributed over several active fault zones within the Central Alborz. Despite earlier efforts using only GPS data, little is known about the long term rate of vertical deformation and aseismic slip. Several historical earthquakes have affected this region, some of the largest of these events occurred on the Mosha fault which is close to the capital city, Tehran, which has a population of over eight million. Thus, constraining the interseismic slip rates in this region is particularly important. In this study we complement existing horizontal velocities from a regional GPS network, with line of sight velocities from interferometric synthetic aperture radar (InSAR), to provide additional constraints on the vertical deformation and enhance the spatial coverage. Assuming a seismogenic depth of 30 km, based on microseismicity data, we solve for the geometry and long term slip rates on four major fault strands in this region. We obtain a long term slip rate of ~ 3 mm/yr for the Mosha and North Alborz faults, and ~ 10 mm/yr for the Khazar fault and Parchin faults. These rates and fault geometries are in agreement with earlier works, and fit the GPS data well. However, close to the fault traces there are large residuals in the InSAR data, suggesting that there is shallow creep (< 30 km). Therefore, we carry out a subsequent inversion using only the residual InSAR displacements to solve for the distribution of creep within the seismogenic zones on these faults. We find that the Mosha and North Alborz faults remain locked between 0 - 30 km depth, whilst the Parchin and Khazar faults are creeping. This new observation of fault creep has direct implications for the seismic hazard in the region. On the Mosha fault we estimate a slip deficit equivalent to a Mw 7.0 event. The combination of In

  16. Geochemistry of middle Tertiary volcanic rocks in the northern Aquarius Mountains, west-central Arizona

    SciTech Connect

    Simmons, A.M.; Haxel, G.B.

    1993-04-01

    The northern Aquarius Mountains volcanic field ([approximately]50km east of Kingman) covers an area of 400 km[sup 2], bounded by upper Trout Creek (S), the Truxton Valley (N), the Big Sandy Valley (W), and Cross Mountain (E). The volcanic sequence rests upon a pre-middle Eocene erosional surface. The lowest units is a 250 m-thick unit of rhyolitic pyroclastic breccias and airfall tuffs. Successively younger units are: basanite flows and cinder cones; hornblende latite flows and domes; porphyritic dacite flows, domes, and breccias; alkali basalt intrusions; and low-silica rhyolite domes and small high=silica rhyolite flows. Dacite is volumetrically dominant, and erupted primarily from vents in and around Cedar Basin (Penitentiary Mtn 7.5[prime] quad.). Other geologists have obtained K-Ar dates [approximately]24--20 Ma for the basanites and latites. The alkali basalts, latites, dacites, and rhyolites evidently constitute a genetically-related high-K to shoshonitic calcalkaline suite with chemistry typical of subduction-related magmatism: enrichment in LILE and LREE, and depletion of Nb and Ta relative to K and La and of Ti relative to Hf and Yb. Each rock type is unique and distinguishable in K/Rb and Rb/Sr. The basanites are primitive (mg=0.75--0.78), have intraplate affinities (La/Nb[<=]1), and show consistent and distinctive depletion of K relative to the other LILE. The presence of these basanites in an early Miocene volcanic sequence is unusual or unexpected, as they predate (by [approximately]10 m.y.) the regional eruption of asthenosphere-derived basalts associated with Basin-and-Range extension.

  17. Holocene vegetation and fire history of the mountains of northern Sicily (Italy)

    USGS Publications Warehouse

    Tinner, Willy; Vescovi, Elisa; Van Leeuwen, Jacqueline; Colombaroli, Daniele; Henne, Paul; Kaltenrieder, Petra; Morales-Molino, Cesar; Beffa, Giorgia; Gnaegi, Bettina; Van der Knaap, Pim W O; La Mantia, Tommaso; Pasta, Salvatore

    2016-01-01

    Knowledge about vegetation and fire history of the mountains of Northern Sicily is scanty. We analysed five sites to fill this gap and used terrestrial plant macrofossils to establish robust radiocarbon chronologies. Palynological records from Gorgo Tondo, Gorgo Lungo, Marcato Cixé, Urgo Pietra Giordano and Gorgo Pollicino show that under natural or near natural conditions, deciduous forests (Quercus pubescens, Q. cerris, Fraxinus ornus, Ulmus), that included a substantial portion of evergreen broadleaved species (Q. suber, Q. ilex, Hedera helix), prevailed in the upper meso-mediterranean belt. Mesophilous deciduous and evergreen broadleaved trees (Fagus sylvatica, Ilex aquifolium) dominated in the natural or quasi-natural forests of the oro-mediterranean belt. Forests were repeatedly opened for agricultural purposes. Fire activity was closely associated with farming, providing evidence that burning was a primary land use tool since Neolithic times. Land use and fire activity intensified during the Early Neolithic at 5000 bc, at the onset of the Bronze Age at 2500 bc and at the onset of the Iron Age at 800 bc. Our data and previous studies suggest that the large majority of open land communities in Sicily, from the coastal lowlands to the mountain areas below the thorny-cushion Astragalus belt (ca. 1,800 m a.s.l.), would rapidly develop into forests if land use ceased. Mesophilous Fagus-Ilex forests developed under warm mid Holocene conditions and were resilient to the combined impacts of humans and climate. The past ecology suggests a resilience of these summer-drought adapted communities to climate warming of about 2 °C. Hence, they may be particularly suited to provide heat and drought-adaptedFagus sylvatica ecotypes for maintaining drought-sensitive Central European beech forests under global warming conditions.

  18. Geology and Volcanology of Kima'Kho Mountain, Northern British Columbia: A Pleistocene Glaciovolcanic Edifice

    NASA Astrophysics Data System (ADS)

    Turnbull, M.; Porritt, L. A.; Edwards, B. R.; Russell, K.

    2014-12-01

    Kima'Kho Mountain is a 1.8 Ma (40Ar/39Ar of 1.82 +/- 40 ka) Pleistocene an alkali-olivine basaltic tuya situated in northern British Columbia. The volcanic edifice rises 460 m from its base and comprises a central vent, dominated by lapilli-tuff and minor pillow lava and dykes; and a surrounding plateau underlain by a sequence of dipping beds of basaltic tuff-breccia and capped by a series of flat-lying, subaerial lava flows. We present a 1:10,000 geological map for Kima'Kho Mountain building on the preliminary work of Ryane et al. (2010). We use the volcanic stratigraphy to explore the implications of three unique features. (1) The central cone comprises massive to crudely-bedded lapilli tuffs containing abundant armoured lapilli - cores of highly-vesicular pyroclasts coated with blocky to cuspate vitric ash. These units suggest an explosive origin from within an ice-enclosed lake, and deposited by wet, dilute pyroclastic surge events. (2) The entire stratigraphic sequence hosts at least two "passage zones" (cf. Jones, 1969); the presence and geometry of these passage zones constrain ice thicknersses at the time of eruption and inform on the englacial lake dynamics. (3) Lastly, our field-based stratigraphic relationships are at odds with the classic tuya model (i.e. an effusive onset to the eruption, forming pillow basalts, followed by explosive activity). Our field mapping suggests an alternative model of tuya architecture, involving a highly-energetic, sustained explosive onset creating a tephra cone that become emergent followed by effusive eruption to create lavas and a subaqueous lava-fed delta. Jones, J. G. Intraglacial volcanoes of the Laugarvatn region, south-west Iceland-I. Geological Society of London Quarterly Journal 124, 197-211 (1969). Ryane, C., Edwards, B. R. & Russell, J. K. The volcanic stratigraphy of Kima'Kho Mountain: A Pleistocene tuya, northwestern British Columbia. Geological Survey of Canada, Current Research 2011-104, 12p, doi:10

  19. Tertiary volcanic rocks and uranium in the Thomas Range and northern Drum Mountains, Juab County, Utah

    USGS Publications Warehouse

    Lindsey, David A.

    1982-01-01

    The Thomas Range and northern Drum Mountains have a history of volcanism, faulting, and mineralization that began about 42 m.y. (million years) ago. Volcanic activity and mineralization in the area can be divided into three stages according to the time-related occurrence of rock types, trace-element associations, and chemical composition of mineral deposits. Compositions of volcanic rocks changed abruptly from rhyodacite-quartz latite (42-39 m.y. ago) to rhyolite (38-32 m.y. ago) to alkali rhyolite (21 and 6-7 m.y. ago); these stages correspond to periods of chalcophile and siderophile metal mineralization, no mineralization(?), and lithophile metal mineralization, respectively. Angular unconformities record episodes of cauldron collapse and block faulting between the stages of volcanic activity and mineralization. The youngest angular unconformity formed between 21 and 7 m.y. ago during basin-and-range faulting. Early rhyodacite-quartz latite volcanism from composite volcanoes and fissures produced flows, breccias, and ash-flow tuff of the Drum Mountains Rhyodacite and Mt. Laird Tuff. Eruption of the Mt. Laird Tuff about 39 m.y. ago from an area north of Joy townsite was accompanied by collapse of the Thomas caldera. Part of the roof of the magma chamber did not collapse, or the magma was resurgent, as is indicated by porphyry dikes and plugs in the Drum Mountains. Chalcophile and siderophile metal mineralization, resulting in deposits of copper, gold, and manganese, accompanied early volcanism. Te middle stage of volcanic activity was characterized by explosive eruption of rhyolitic ash-flow tuffs and collapse of the Dugway Valley cauldron. Eruption of the Joy Tuff 38 m.y. ago was accompanied by subsidence of this cauldron and was followed by collapse and sliding of Paleozoic rocks from the west wall of the cauldron. Landslides in The Dell were covered by the Dell Tuff, erupted 32 m.y. ago from an unknown source to the east. An ash flow of the Needles Range

  20. [Characteristics of macropores in two forest soils on northern slope of Changbai Mountains].

    PubMed

    Li, Wei-li; Jin, Chang-jie; Wang, An-zhi; Pei, Tie-fan; Guan, De-xin

    2007-06-01

    By using dye tracing and image analysis, the characteristics and distribution of macropores in brown coniferous forest soil and dark brown forest soil on northern slope of Changbai Mountains were studied, with the factors affecting the formation of the macropores discussed. The results showed that the vertical distribution pattern of soil macropores could be indirectly known by the variation of dyed area with soil depth. The dyed area of the two soils tended to decrease with increasing soil depth. In 24 hours, the macropore flow transferred 10-20 cm deeper in brown coniferous forest soil than in dark brown forest soil, and there were more macropore flow paths in brown coniferous forest soil. By unit area, brown coniferous forest soil had 6 paths, while dark brown forest soil only had 1 path. The existence of macropore flow could accelerate the infiltration speed by 2 or 3 times at least. Bio-factor was the key factor affecting the formation of macropores in the two kinds of forest soil. There were more macropores formed by soil animals, and the diameter was mostly between 2 and 4 mm. PMID:17763718

  1. Age and tectonic setting of Mesozoic metavolcanic and metasedimentary rocks, northern White Mountains, California

    NASA Astrophysics Data System (ADS)

    Hanson, R. Brooks; Saleeby, Jason B.; Fates, D. Gilbert

    1987-11-01

    Mesozoic metavolcanic and metasedimentary rocks in the northern White Mountains, eastern California and western Nevada, are separated from lower Paleozoic and Precambrian rocks by Jurassic and Cretaceous plutons. The large stratigraphic hiatus across the plutons is called the Barcroft structural break. Recent mapping and new U/Pb zircon ages of 154 +3/-1 Ma and 137 ±1 Ma. from an ash-flow tuff and a hypabyssal intrusion, respectively, indicate that part of the Mesozoic section and the Barcroft structural break are younger than the 160 165 Ma Barcroft Granodiorite, in contrast to previous interpretations. The Barcroft Granodiorite has been thrust westward over most of the Mesozoic section. It is everywhere in fault contact with overturned metasedimentary rocks on the west side of the range, rocks which were previously thought to be upright and the oldest part of the Mesozoic section. The McAfee Creek Granite, which has a 100 ±1 Ma U/Pb zircon age, postdates thrusting; therefore, the Barcroft structural break is primarily Early Cretaceous in age. *Present addresses: Hanson—Department of Mineral Sciences, Smithsonian Institution, Washington, D.C. 20560; Fates—Dames & Moore, 455 S. Figueroa Street, Suite 3504, Los Angeles, California 90074

  2. Adapting Natural Resource Management to Climate Change: The Blue Mountains and Northern Rockies Adaptation Partnerships

    NASA Astrophysics Data System (ADS)

    Halofsky, J.; Peterson, D. L.

    2014-12-01

    Concrete ways to adapt to climate change are needed to help natural resource managers take the first steps to incorporate climate change into management and take advantage of opportunities to balance the negative effects of climate change. We recently initiated two science-management climate change adaptation partnerships, one with three national forests and other key stakeholders in the Blue Mountains region of northeastern Oregon, and the other with 16 national forests, three national parks and other stakeholders in the northern Rockies region. Goals of both partnerships were to: (1) synthesize published information and data to assess the exposure, sensitivity, and adaptive capacity of key resource areas, including water use, infrastructure, fisheries, and vegetation and disturbance; (2) develop science-based adaptation strategies and tactics that will help to mitigate the negative effects of climate change and assist the transition of biological systems and management to a warmer climate; (3) ensure adaptation strategies and tactics are incorporated into relevant planning documents; and (4) foster an enduring partnership to facilitate ongoing dialogue and activities related to climate change in the partnerships regions. After an initial vulnerability assessment by agency and university scientists and local resource specialists, adaptation strategies and tactics were developed in a series of scientist-manager workshops. The final vulnerability assessments and adaptation actions are incorporated in technical reports. The partnerships produced concrete adaptation options for national forest and other natural resource managers and illustrated the utility of place-based vulnerability assessments and scientist-manager workshops in adapting to climate change.

  3. [Distribution and characteristics of soil antagonistic actinomycetes on northern slope of Taibai Mountain, Qinling].

    PubMed

    Zhu, Wen-Jie; Xue, Quan-Hong; Cao, Yan-Ru; Xue, Lei; Shen, Guang-Hui; Lai, Hang-Xian

    2011-11-01

    Twelve representative soil samples were collected from different altitudes on the northern slope of Taibai Mountain to study the distribution and characteristics of soil antagonistic actinomyces by using agar block method. There existed a great deal of soil antagonistic actinomyces in the study area. Among the 141 actinomycete strains isolated, 116 strains (82.3%) showed antagonism toward 12 target bacteria or fungi. The antagonistic strains at altitudes 800-1845, 3488, 3655, and 3670 m occupied 73.7% -86.8%, 81.3%, 78.9% and 82.3% of the total, respectively. 42.1% of the strains at altitudes 1200-2300 m and > 3400 m showed strong and broad spectrum antagonistic activity, suggesting that there was a great potential for the isolation of actinomycete strains with strong anti-biotic capability at these altitudes. 24.1% of the antagonistic actinomycetes showed antagonism against Staphyloccocus aureu, and 2.4%, 6.9% and 11.2% of them showed activity toward Verticillium dahliae in cotton, Phytophthora sp. in strawberry and Neonectria radiciccla in ginseng, respectively. This study showed that the soil actinomycete antagonistic potentiality (SAAP) could be used as a quantitative indicator to evaluate the potential of antagonistic actinomycete resources in soil. PMID:22303680

  4. Coal in the Northern Rocky Mountains and Great Plains Region -- Clean, compliant, and available

    SciTech Connect

    Stricker, G.D.; Ellis, M.S.; Flores, R.M.; Bader, L.R.

    1998-12-31

    The Northern Rocky Mountains and Great Plains region produced over 340 million short tons of coal in 1997, approximately 30 percent of the nation`s total coal production. Coals from this region are shipped to 26 states in the western, midwest, southern, and eastern US and production is projected to increase to 415 million short tons by 2015; the projected increase will be utilized primarily for production of electric power. The coals are economically attractive because they can be produced by surface mining, and do not require costly beneficiation to be compliant with emission standards. The coals are compliant because their chemical composition was influenced by tectonic settings of the coal basins and provenance of the sediments entering the basins. Tectonics during the Paleocene also influenced rates of precipitation and depositional systems. These factors, in concert, controlled the amount, distribution, and levels of sulfur, ash, and trace elements of environmental concern in the region`s coals. The emphasis of this paper is on the chemistry of these thick, high-quality coals and the geologic controls that resulted in their accumulation.

  5. Grasshopper (Orthoptera: Acrididae) Community Composition in the Rangeland of the Northern Slopes of the Qilian Mountains in Northwestern China

    PubMed Central

    Sun, T.; Liu, Z. Y.; Qin, L. P.; Long, R. J.

    2015-01-01

    In order to describe grasshopper (Orthoptera: Acrididae) species composition, diversity, abundance, and density of four rangelands types, we compared the grasshopper community composition and dynamics in the rangeland of the northern slopes of the Qilian Mountains. In total, 55 grasshopper species were collected from 2007 to 2009, representing three families and six subfamilies. The subfamily Oedipodinae was dominant, followed by Gomphocerinae and Catantopinae. Species abundance varied among rangeland types (RTs). The greatest abundance of grasshoppers was found in mountain rangeland, while the lowest abundance of grasshoppers was caught in alpine shrublands. Three species (Chorthippus cf. brunneus (Thunberg) (Acrididae), Chorthippus Dubius (Zubovski), and Gomphocerus licenti (Chang) were broadly distributed in the four RTs and constituted 7.5% of all grasshoppers collected. Ch. dubius was very abundant in desert rangeland and alpine shrubland. Bryodema dolichoptera Yin et Feng Eremippus qilianshanensis Lian and Zheng, and Filchnerella qilianshanensis Xi and Zheng (Pamphagidae) were endemic to the region of the Qilian Mountains. Species similarity between RTs ranged from 17.8 to 51.6 based on the Renkonen index. Similarly, the Sörensen index indicated a wide separation in species composition among RTs. The abundance of the eight most common species showed obvious differences among RTs and years. On average, mountain rangeland had the highest density values in 2007 and 2008, and alpine shrubland supported the smallest density. The densities in desert and mountain rangeland in 2007 were significantly higher than in 2008, while alpine rangeland and shrublands did not present obvious differences among years. PMID:25688084

  6. Grasshopper (Orthoptera: Acrididae) community composition in the rangeland of the northern slopes of The Qilian Mountains in northwestern China.

    PubMed

    Sun, T; Liu, Z Y; Qin, L P; Long, R J

    2015-01-01

    In order to describe grasshopper (Orthoptera: Acrididae) species composition, diversity, abundance, and density of four rangelands types, we compared the grasshopper community composition and dynamics in the rangeland of the northern slopes of the Qilian Mountains. In total, 55 grasshopper species were collected from 2007 to 2009, representing three families and six subfamilies. The subfamily Oedipodinae was dominant, followed by Gomphocerinae and Catantopinae. Species abundance varied among rangeland types (RTs). The greatest abundance of grasshoppers was found in mountain rangeland, while the lowest abundance of grasshoppers was caught in alpine shrublands. Three species (Chorthippus cf. brunneus (Thunberg) (Acrididae), Chorthippus Dubius (Zubovski), and Gomphocerus licenti (Chang) were broadly distributed in the four RTs and constituted 7.5% of all grasshoppers collected. Ch. dubius was very abundant in desert rangeland and alpine shrubland. Bryodema dolichoptera Yin et Feng Eremippus qilianshanensis Lian and Zheng, and Filchnerella qilianshanensis Xi and Zheng (Pamphagidae) were endemic to the region of the Qilian Mountains. Species similarity between RTs ranged from 17.8 to 51.6 based on the Renkonen index. Similarly, the Sörensen index indicated a wide separation in species composition among RTs. The abundance of the eight most common species showed obvious differences among RTs and years. On average, mountain rangeland had the highest density values in 2007 and 2008, and alpine shrubland supported the smallest density. The densities in desert and mountain rangeland in 2007 were significantly higher than in 2008, while alpine rangeland and shrublands did not present obvious differences among years. PMID:25688084

  7. Regional Hydraulic Geometry Curves of the Northern Cascade Mountains, Chelan and King Counties, Washington State, USA

    NASA Astrophysics Data System (ADS)

    Gasperi, J. T.; McClung, J. M.; Hanson, D. L.

    2006-12-01

    The USDA-Natural Resources Conservation Service has developed regional hydraulic geometry curves relating drainage area to bankfull top width, mean depth and cross-sectional area for the east and west sides of the northern Cascade Mountains in Chelan and King Counties, Washington. NRCS surveyed 10 channel reaches with drainage areas from 1 to 1000 square miles within the Wenatchee River drainage of Chelan County and 10 channel reaches with drainage areas of 1 to 100 square miles within the Cedar and Green River drainages of King County. Selection criteria for stream reaches required a minimum of 20 years of USGS stream gage discharge records, unregulated flows and safe access. Survey data were collected with a Sokkia Total Station during low flow conditions from August 2004 to September 2005. NRCS measured a channel cross-section at each of the USGS stream gage sites and two or three additional cross-sections up and downstream. The authors also collected samples of bed material for gradation analysis and estimation of Manning's roughness coefficient, n. Bankfull elevations were estimated based on visual identification of field indicators and USGS flood discharges for the 50% exceedance probability event. Field data were evaluated with the Ohio DNR Reference Reach spreadsheet to determine bankfull top width, mean depth and cross-sectional area. We applied a simple linear regression to the data following USGS statistical methods to evaluate the closeness of fit between drainage area and bankfull channel dimensions. The resulting R2 values of 0.83 to 0.93 for the eastern Cascade data of Chelan County and 0.71 to 0.88 for the western Cascade data of King County indicate a close association between drainage area and bankfull channel dimensions for these two sets of data.

  8. Survey of glaciers in the northern Rocky Mountains of Montana and Wyoming; Size response to climatic fluctuations 1950-1996

    SciTech Connect

    Chatelain, E.E.

    1997-09-01

    An aerial survey of Northern Rocky Mountain glaciers in Montana and Wyoming was conducted in late summer of 1996. The Flathead, Swan, Mission, and Beartooth Mountains of Montana were covered, as well as the Teton and Wind River Ranges of Wyoming. Present extent of glaciers in this study were compared to limits on recent USGS 15 and 7.5 topographic maps, and also from selected personal photos. Large cirque and hanging glaciers of the Flathead and Wind River Ranges did not display significant decrease in size or change in terminus position. Cirque glaciers in the Swan, Mission, Beartooth and Teton Ranges were markedly smaller in size; with separation of the ice body, growth of the terminus lake, or cover of the ice terminus with rockfalls. A study of annual snowfall, snowdepths, precipitation, and mean temperatures for selected stations in the Northern Rocky Mountains indicates no extreme variations in temperature or precipitation between 1950-1996, but several years of low snowfall and warmer temperatures in the 1980`s appear to have been sufficient to diminish many of the smaller cirque glaciers, many to the point of extinction. The disappearance of small cirque glaciers may indicate a greater sensitivity to overall climatic warming than the more dramatic fluctuations of larger glaciers in the same region.

  9. Provenance of Neoproterozoic sedimentary basement of northern Iran, Kahar Formation

    NASA Astrophysics Data System (ADS)

    Etemad-Saeed, Najmeh; Hosseini-Barzi, Mahboubeh; Adabi, Mohammad Hossein; Sadeghi, Abbas; Houshmandzadeh, Abdolrahim

    2015-11-01

    This article presents new data to understand the nature of the hidden crystalline basement of northern Iran and the tectonic setting of Iran during late Neoproterozoic time. The siliciclastic-dominated Kahar Formation represents the oldest known exposures of northern Iran and comprises late Ediacaran (ca. 560-550 Ma) compositionally immature sediments including mudrocks, sandstones, and conglomerates. This work focuses on provenance of three well preserved outcrops of this formation in Alborz Mountains: Kahar Mountain, Sarbandan, and Chalus Road, through petrographic and geochemical methods. Mineralogical Index of Alteration (MIA) and Chemical Index of Alteration (CIA-after correction for K-metasomatism) values combined with A-CN-K relations suggest moderate weathering in the source areas. The polymictic nature of Kahar conglomerates indicates a mixed provenance for them. However, modal analysis of Kahar sandstones (volcanic to plagioclase-rich lithic arkose) and whole rock geochemistry of mudrocks suggest that they are largely first-cycle sediments and that their sources were remarkably late Ediacaran, intermediate-felsic igneous rocks from proximal arc settings. Tectonic setting discrimination diagrams also indicate a convergent plate margin and continental arc related basin for Kahar sediments. This interpretation is supported by the phyllo-tectic to tectic composition and geochemistry of mudrocks. These results reveal the presence of a felsic/intermediate subduction-related basement (∼600-550 Ma) in this region, which provides new constraints on subduction scenario during this time interval in Iran, as a part of the Peri-Gondwanan terranes.

  10. Integrative geomorphological mapping approach for reconstructing meso-scale alluvial fan palaeoenvironments at Alborz southern foothill, Damghan basin, Iran

    NASA Astrophysics Data System (ADS)

    Büdel, Christian; Majid Padashi, Seyed; Baumhauer, Roland

    2013-04-01

    Alluvial fans and aprons are common depositional features in general Iranian geomorphology. The countries major cities as well as settlements and surrounding area have often been developed and been built up on this Quaternary sediment covers. Hence they periodically face the effects of varying fluvial and slope-fluvial activity occurring as part of this geosystem. The Geological Survey of Iran therefore supports considerable efforts in Quaternary studies yielding to a selection of detailed mapped Quaternary landscapes. The studied geomorphologic structures which are settled up around an endorheic basin in Semnan Province represent a typical type of landform configuration in the area. A 12-km-transect was laid across this basin and range formation. It is oriented in north-south direction from the southern saltpan, called "Kavir-e-Haj Aligholi"/"Chah-e-Jam" ("Damghan Kavir"), across a vast sandy braided river plain, which is entering from the north east direction of the city of Shahroud. At its northern rim it covers alluvial sediment bodies, which are mainly constituted by broad alluvial aprons, fed by watersheds in Alborz Mountains and having their genetic origins in Mio-/Pliocene times. During this study a fully analytical mapping system was used for developing a geodatabase capable of integrating geomorphological analyses. Therefore the system must provide proper differentiation of form, material and process elements as well as geometric separation. Hence the German GMK25 system was set up and slightly modified to fit to the specific project demands. Due to its structure it offers most sophisticated standards and scale independent hierarchies, which fit very well to the software-determinated possibilities of advanced geodatabase applications. One of the main aspects of mapping Quaternary sediments and structures is to acquire a proper description and systematic correlation and categorization of the belonging mapping-objects. Therefore the team from GSI and

  11. Post-collisional transition from an extensional volcano-sedimentary basin to a continental arc in the Alborz Ranges, N-Iran

    NASA Astrophysics Data System (ADS)

    Asiabanha, Abbas; Foden, John

    2012-09-01

    The Alborz Magmatic Assemblage (AMA) is an Eocene volcanic complex in northern Iran, and is situated at the site of the closure of the Tethyan basin. The magmatic rocks of the Alborz assemblage exhibit a distinct progression in style, from shallow submarine explosive eruptions to more effusive sub-aerial eruptions. Their chemical compositions indicate that they belong to the high-K calc-alkaline (shoshonitic) suite, and are related to either a subduction regime or continental collision. This conclusion is verified by major and trace element abundances, such as enrichments in Light Rare Earth Elements (LREEs) and Large Ion Lithophile Elements (LILEs) (e.g., K, U, and Sr) and depletion in High Field Strength Elements (HFSEs) (e.g., Nb, Ta, Ti, and Zr). However, HFSE plots suggest that the source region of the AMA magmas was affected by multiple processes, including deeply subducted lithosphere and the partial melts of extensional lithosphere in a back-arc environment. The isotopic composition of this suite and their trace element ratios suggest that the primary magmas were derived from a depleted mantle source and were subsequently affected by both fractional crystallization (ol + cpx in basic magmas and plg + bio ± hbl in intermediate magmas) and assimilation during magmatic evolution. Assimilation and fractional crystallization modeling, based on isotopic and trace element ratios, indicates that the ascending magmas were contaminated by approximately 40% continental crust. The petrography and geochemical composition of the Eocene Alborz magmatic assemblage indicate that it developed in a back-arc basin, in which explosive eruptions produced various pyroclastic and epiclastic deposits. A subsequent stage of volcanism then produced more effusive sub-aerial eruptions, as well as sporadic explosions that generated ignimbritic sheets.

  12. Simulation modeling and preliminary analysis of TIMS data from the Carlin area and the northern Grapevine Mountains, Nevada

    NASA Technical Reports Server (NTRS)

    Watson, Ken; Hummer-Miller, Susanne; Kruse, Fred A.

    1986-01-01

    A theoretical radiance model was employed together with laboratory data on a suite of igneous rock to evaluate various algorithms for processing Thermal Infrared Multispectral Scanner (TIMS) data. Two aspects of the general problem were examined: extraction of emissivity information from the observed TIMS radiance data, and how to use emissivity data in a way that is geologically meaningful. The four algorithms were evaluated for appropriate band combinations of TIMS data acquired on both day and night overflights of the Tuscarora Mountains, including the Carlin gold deposit, in north-central Nevada. Analysis of a color composited PC decorrelated image (Bands 3, 4, 5--blue/green/red) of the Northern Grapevine Mountains, Nevada, area showed some useful correlation with the regional geology. The thermal infrared region provides fundamental spectral information that can be used to discriminate the major rock types occurring on the Earth's surface.

  13. Appalachian Mountains

    Atmospheric Science Data Center

    2014-05-15

    article title:  Appalachian Mountains     View Larger Image Multi-angle views of the Appalachian Mountains, March 6, 2000 . The true-color image at left is a ... from Lake Ontario to northern Georgia, and spanning the Appalachian Mountains. The three images to the right are also in true-color, ...

  14. Diatom Community Changes in Five Sub-alpine Mountain Lakes in Northern California

    NASA Astrophysics Data System (ADS)

    Johnson, B.; Noble, P. J.; Howard, K.; Heyvaert, A.

    2012-12-01

    Sediment cores and/or phytoplankton sampling of five sub-alpine lakes within three northern California mountain ranges show a major shift in diatom phytoplankton communities over the past 20-60 years; however, specific causes of these changes are still under investigation. Diatom analysis of a 20-cm sediment core taken from Castle Lake, a meso-oligotrophic lake located on the eastern slope of the Klammath Mountains, shows the phytoplankton community shifted from being cyclotelloid-dominated to having a larger component of araphids beginning around 1997. In the lower 14 cm of the core, the phytoplankton are dominated by centric diatoms, including the Discostella stelligera-pseudostelligera group (>50% of total diatoms), and the Cyclotella occelata-rossii-tripartita complex (9-18%). The top 6 cm show an increasing shift towards araphids, including Asterionella formosa and the Fragilaria tenera-nanana group, which is consistent with phytoplankton in the lake's epilimnion today. Fallen Leaf Lake (FLL), located at the southern end of the Lake Tahoe basin, has also undergone a similar shift. Presently, A. formosa, the F. tenera-nananna group, and Tabellaria dominate the phytoplankton. Examination of a sediment core from FLL indicates that A. formosa has been present in high abundances since at least 1812. The most prominent shift in the FLL diatom population began in the 1950s when the centric diatoms (eg. Aulacoseira subarctica) declined significantly in favor of araphids. The F. tenera-nanana group was present in trace amounts before 1812 and dramatically increased in abundance after the 1950s. Sediment accumulation rates have increased steadily since 1950 and coincide with increases in lake development and recreational use. A. formosa is also present today in Gilmore Lake, a minimally human-impacted lake located in the watershed above FLL, and in the heavily impacted Manzanita Lake in the northwestern corner of Lassen Volcanic National Park (LAVO) at the southern end

  15. Study of Magnetic Fabrics and Paleomagnetism Across Northern Transect of Taiwan Mountain Belt and Thier Implications

    NASA Astrophysics Data System (ADS)

    Yeh, E. C.; Peng, X. J.; Tseng, Y. C.; Chou, Y. M.; Lee, T. Q.; Aubourg, C.; Chen, C. C.; Lin, S. T.; Chen, C. T.

    2015-12-01

    Anisotropy of magnetic susceptibility (AMS) can be regarded as a useful tool for understanding the variation of finite strain pattern for regional deformation. In order to evaluate the interrelationship between maximum metamorphic temperature and deformation during mountain building, oriented samples of low-grade metamorphic rocks across the northern Taiwan were collected. In addition to the study of magnetic susceptibility anisotropy, experiments of natural remanent magnetization, hysteresis loop, and temperature-function magnetic susceptibility were also conducted. Results show that K1 orientation of magnetic ellipsoids suggested NW-SE compression, which is consistent with plate convergence direction. Both deformation intensity and anisotropy increase from the west to east with abnormally strong intensity and oblate strain near major faults. Magnetic fabrics have grouped six-stage from Type I to VI upon increasing strain. Study area can be divided into four domain A to D by geological characteristics and distribution of magnetic fabric. Rocks in Domain A begin to be influenced by horizontal tectonic strain. Ellipsoid is oblate and K1 is in northeast-southwest orientation, indicating NW-SW compression. Magnetic fabric belongs to Type II. K3 orientation in Domain B started to be affected by cleavage. The shape of ellipsoid is mainly oblate. Magnetic fabric is classified as Type II-III. The shape of ellipsoid in Domain C gradually converts to prolate. Distribution of K3, influenced by cleavage development, becomes a girdle in NW-SE orientation. It is treated as Type III-IV. In Domain D, though both anisotropy and deformation intensity are increased, the direction of K3 is still concentrated in vertical, not in horizontal. Results might be the reflective of discontinuous strain response to different kinematic mechanisms between the Backbone Range and the Hsueshan Range. Thermopaleogeomagnetic records of pyrrhotite remanence on both limbs of the Chungling Anticline

  16. Effects of Debris Flows on Stream Ecosystems of the Klamath Mountains, Northern California

    NASA Astrophysics Data System (ADS)

    Cover, M. R.; Delafuente, J. A.; Resh, V. H.

    2006-12-01

    We examined the long-term effects of debris flows on channel characteristics and aquatic food webs in steep (0.04-0.06 slope), small (4-6 m wide) streams. A large rain-on-snow storm event in January 1997 resulted in numerous landslides and debris flows throughout many basins in the Klamath Mountains of northern California. Debris floods resulted in extensive impacts throughout entire drainage networks, including mobilization of valley floor deposits and removal of vegetation. Comparing 5 streams scoured by debris flows in 1997 and 5 streams that had not been scoured as recently, we determined that debris-flows decreased channel complexity by reducing alluvial step frequency and large woody debris volumes. Unscoured streams had more diverse riparian vegetation, whereas scoured streams were dominated by dense, even-aged stands of white alder (Alnus rhombiflia). Benthic invertebrate shredders, especially nemourid and peltoperlid stoneflies, were more abundant and diverse in unscoured streams, reflecting the more diverse allochthonous resources. Debris flows resulted in increased variability in canopy cover, depending on degree of alder recolonization. Periphyton biomass was higher in unscoured streams, but primary production was greater in the recently scoured streams, suggesting that invertebrate grazers kept algal assemblages in an early successional state. Glossosomatid caddisflies were predominant scrapers in scoured streams; heptageniid mayflies were abundant in unscoured streams. Rainbow trout (Oncorhynchus mykiss) were of similar abundance in scoured and unscoured streams, but scoured streams were dominated by young-of-the-year fish while older juveniles were more abundant in unscoured streams. Differences in the presence of cold-water (Doroneuria) versus warm-water (Calineuria) perlid stoneflies suggest that debris flows have altered stream temperatures. Debris flows have long-lasting impacts on stream communities, primarily through the cascading effects of

  17. Low Temperature Paleogene Thermal Evolution of the British Mountains using Apatite U-Th/He Dating, Northern Yukon, Canada

    NASA Astrophysics Data System (ADS)

    Pickering, J. E.; Guest, B.; Schneider, D. A.; Lane, L.

    2014-12-01

    The age and rate of exhumation of the British Mountains is tied to the timing of deformation in the Beaufort Sea, an active site for hydrocarbon exploration. This region contains a large portion of North America's oil and gas reserves. The British Mountains, the eastern extent of the Brooks Range in Alaska, include Paleogene structures that are the onshore portion of the Beaufort fold belt. In the Beaufort Sea, deformation is dominated by thin-skinned folding and thrusting of Paleocene to Oligocene sediments that is sourced from the British Mountains. Onshore, Paleogene deformation overprints multiple older structural events. The low temperature time history of the onshore Paleogene structures will be determined through U-Th/He dating of apatites (AHe). The results will contribute to better understanding of the timing of the maturation and migration of hydrocarbons in the Beaufort Sea. Previous work on the thermal history of northern Yukon and the North Slope of Alaska provides a regional framework for the region's low temperature-time history. These regional studies of the northern Yukon and Alaska yielded Paleocene to Eocene (60Ma - 40Ma) apatite fission track (AFT) cooling ages that progressively young to the north, consistent with geological evidence for northward propagating deformation. The British Mountains consist of Neoproterozoic to early Paleozoic marine sediments that are intruded by scattered Devonian plutons; both rock types will be included in the study. This study aims to improve the understanding of the Paleogene tectonic activity of the British Mountains and the deformation history of the Beaufort fold belt. The two data sets, existing AFT and new AHe results, will be both be included in the interpretation of the study area. We will present AHe data to better constrain the onshore exhumation and deformation rates at low temperatures (~60-90°C). A sampled transect through the British mountains, along the Firth River valley will provide good

  18. 40Ar/39Ar dates from alkaline intrusions of the northern Crazy Mountains, south-central Montana

    NASA Astrophysics Data System (ADS)

    Harlan, S. S.

    2005-05-01

    The Crazy Mountains basin of south-central Montana is a complex foreland basin that formed during the interaction of thin-skinned, decollement-style folds of the Montana thrust belt and the basement-involved folds and thrust faults of the Rocky Mountain foreland province. Near the depositional center of the basin, synorogenic strata of the Paleocene Fort Union Formation have been intruded and locally thermally metamorphosed by strongly alkaline to subalkaline Tertiary intrusive rocks. The subalkaline rocks are found mostly in the southern Crazy Mountains and form stocks (Big Timber stock, Loco Mountain stock), radiating dikes and sills. With the exception of the Ibex Mountain sill (?), the alkaline rocks are restricted to the northern Crazy Mountains. New 40Ar/39Ar dates are reported from the strongly alkaline rocks, including the Comb Creek stock and dike swarm, the Ibex Mountain sill(?), and sills from the Robinson anticline intrusive complex. The alkaline rocks of the Robinson anticline intrusive complex are exposed in the easternmost folds of the Cordilleran fold and thrust belt, but despite their arcuate and apparently folded map geometry they have been shown to post-date folding. Hornblende from a trachyte sill in the Robinson anticline intrusive complex yielded a relatively simple age spectrum with a weighted mean of 50.61 ± 0.14 Ma (2σ), which probably records the age of sill emplacement. Nepheline syenite and mafic nepheline syenites of the Comb Creek stock and a dike from its radial dike swarm, two sills from the Robinson antlicline intrusive complex, and the Ibex Mountains sill(?) gave biotite plateau dates ranging from 50.03 to 50.22 Ma, with 2σ errors of ± 0.11 to 0.19 Ma. Because these dates are from fairly small, hypabyssal intrusions, they must have cooled quickly and thus these dates closely approximate the emplacement age of the intrusions. These data indicate that the strongly alkaline intrusions were emplaced during a fairly restricted

  19. Effects of changes in vegetation on precipitation in the northern Tianshan Mountains evaluated using multiple time scales

    NASA Astrophysics Data System (ADS)

    Sun, Qinming; Liu, Tong; Han, Zhiquan; Wu, Yongping; Li, Bai-Lian

    2016-04-01

    This study used a combination of the wavelet cross-correlation technique and numerical analysis of vegetative feedback to study the role of climate-vegetation feedback from 1981 to 2009 in the northern Tianshan Mountains, Xinjiang Province, China. The study area included the Irtysh River, the Bortala and Ili River valleys, the northern slopes of the Tianshan Mountains, and the western Junggar Basin. The feedback effects of changes in vegetation on precipitation appeared to vary in these five regions when different time scales are used to examine them. The most useful time scale was generally found to be 4-6 months. Time lag was another characteristic of this process, and the optimal time lag was 3-4 months. Nevertheless, optimal time scale and time lag did not differ significantly in these five regions. In this way, the correct time scale of the effects of variations in vegetation on precipitation in this cold, arid area was found. This time scale and time lag can be assessed through wavelet cross-correlation analysis. Then numerical analysis can be used to improve the accuracy of the analysis.

  20. Utility of high-altitude infrared spectral data in mineral exploration: Application to Northern Patagonia Mountains, Arizona

    USGS Publications Warehouse

    Berger, B.R.; King, T.V.V.; Morath, L.C.; Phillips, J.D.

    2003-01-01

    Synoptic views of hydrothermal alteration assemblages are of considerable utility in regional-scale minerals exploration. Recent advances in data acquisition and analysis technologies have greatly enhanced the usefulness of remotely sensed imaging spectroscopy for reliable alteration mineral assemblages mapping. Using NASA's Airborne Visible Infrared Imaging Spectrometer (AVIRIS) sensor, this study mapped large areas of advanced argillic and phyllic-argillic alteration assemblages in the southeastern Santa Rita and northern Patagonia mountains, Arizona. Two concealed porphyry copper deposits have been identified during past exploration, the Red Mountain and Sunnyside deposits, and related published hydrothermal alteration zoning studies allow the comparison of the results obtained from AVIRIS data to the more traditional field mapping approaches. The AVIRIS mapping compares favorably with field-based studies. An analysis of iron-bearing oxide minerals above a concealed supergene chalcocite deposit at Red Mountain also indicates that remotely sensed data can be of value in the interpretation of leached caps above porphyry copper deposits. In conjunction with other types of geophysical data, AVIRIS mineral maps can be used to discriminate different exploration targets within a region.

  1. Precipitation and Air Pollution at Mountain and Plain Stations in Northern China: Insights Gained from Observations and Modeling

    SciTech Connect

    Guo, Jianping; Deng, Minjun; Fan, Jiwen; Li, Zhanqing; Chen, Qian; Zhai, Panmao; Dai, Zhijian; Li, Xiaowen

    2014-04-27

    We analyzed 40 year data sets of daily average visibility (a proxy for surface aerosol concentration) and hourly precipitation at seven weather stations, including three stations located on the Taihang Mountains, during the summertime in northern China. There was no significant trend in summertime total precipitation at almost all stations. However, light rain decreased, whereas heavy rain increased as visibility decreased over the period studied. The decrease in light rain was seen in both orographic-forced shallow clouds and mesoscale stratiform clouds. The consistent trends in observed changes in visibility, precipitation, and orographic factor appear to be a testimony to the effects of aerosols. The potential impact of large-scale environmental factors, such as precipitable water, convective available potential energy, and vertical wind shear, on precipitation was investigated. No direct links were found. To validate our observational hypothesis about aerosol effects, Weather Research and Forecasting model simulations with spectral-bin microphysics at the cloud-resolving scale were conducted. Model results confirmed the role of aerosol indirect effects in reducing the light rain amount and frequency in the mountainous area for both orographic-forced shallow clouds and mesoscale stratiform clouds and in eliciting a different response in the neighboring plains. The opposite response of light rain to the increase in pollution when there is no terrain included in the model suggests that orography is likely a significant factor contributing to the opposite trends in light rain seen in mountainous and plain areas.

  2. Ubiquitous Low-Velocity Layer Atop the 410-km Discontinuity in the Northern Rocky Mountains

    NASA Astrophysics Data System (ADS)

    Jasbinsek, J. J.; Dueker, K. G.

    2006-12-01

    Receiver functions (RF) from three 30-station IRIS-PASSCAL small aperture arrays (2-15 km station spacing) operated for ten months each in the northern Rocky Mountains show a ubiquitous negative polarity P to S arrival (NPA) just preceding the 410-km discontinuity arrival. Data from the arrays was divided into NW, SE and SW backazimuths and stacked to form nine quadrant stacks (QS). Remarkably, the NPA is apparent in 8 of the 9 QS, with 7 of the 8 displaying a similar dipole shape (paired negative and positive swings). Each QS contains clear P to S arrivals from the 410- and 660-km discontinuities and display the correct moveout. To model the NPA, a "double gradient slab" model consisting of five parameters is used: top gradient thickness and shear wave velocity drop; a constant velocity layer; bottom gradient thickness and shear wave velocity increase. Model misfit is assessed via a grid search over the model space using a reflectivity code to calculate synthetic seismograms. Assessment of model likelihood is done by calculating 1- and 2-D marginal probability density functions (PDF). Model parameters for each QS are well resolved and uncorrelated, with the exception of the anti-correlation of the top and bottom gradients. To define an average model, the probability distributions of each QS for each parameter are multiplied to form summary 1-D marginal PDF from which 90% probability bounds are calculated. These probability bounds are: the top gradient is < 8 km with a velocity decrement of 0.3-0.5 km/s; the constant velocity layer thickness is < 5 km; and, the bottom gradient is 29-37 km with a velocity increase of 0.4-0.6 km/s. The effective width of the low velocity layer atop the 410 (herein called the 410-LVL) is characterized as the layer thickness plus half the two gradient widths. Thus, the 410-LVL is found to have a mean thickness of 26 km and a mean shear wave velocity decrement of 8.3%. These results contrast with 410-LVL widths of 25-90 km and shear

  3. Spatiotemporal analysis of Quaternary normal faults in the Northern Rocky Mountains, USA

    NASA Astrophysics Data System (ADS)

    Davarpanah, A.; Babaie, H. A.; Reed, P.

    2010-12-01

    The mid-Tertiary Basin-and-Range extensional tectonic event developed most of the normal faults that bound the ranges in the northern Rocky Mountains within Montana, Wyoming, and Idaho. The interaction of the thermally induced stress field of the Yellowstone hot spot with the existing Basin-and-Range fault blocks, during the last 15 my, has produced a new, spatially and temporally variable system of normal faults in these areas. The orientation and spatial distribution of the trace of these hot-spot induced normal faults, relative to earlier Basin-and-Range faults, have significant implications for the effect of the temporally varying and spatially propagating thermal dome on the growth of new hot spot related normal faults and reactivation of existing Basin-and-Range faults. Digitally enhanced LANDSAT 7 Enhanced Thematic Mapper Plus (ETM+) and Landsat 4 and 5 Thematic Mapper (TM) bands, with spatial resolution of 30 m, combined with analytical GIS and geological techniques helped in determining and analyzing the lineaments and traces of the Quaternary, thermally-induced normal faults in the study area. Applying the color composite (CC) image enhancement technique, the combination of bands 3, 2 and 1 of the ETM+ and TM images was chosen as the best statistical choice to create a color composite for lineament identification. The spatiotemporal analysis of the Quaternary normal faults produces significant information on the structural style, timing, spatial variation, spatial density, and frequency of the faults. The seismic Quaternary normal faults, in the whole study area, are divided, based on their age, into four specific sets, which from oldest to youngest include: Quaternary (>1.6 Ma), middle and late Quaternary (>750 ka), latest Quaternary (>15 ka), and the last 150 years. A density map for the Quaternary faults reveals that most active faults are near the current Yellowstone National Park area (YNP), where most seismically active faults, in the past 1.6 my

  4. The northern Sacramento Mountains, southwest United States. Part II: Exhumation history and detachment faulting

    USGS Publications Warehouse

    Pease, V.; Foster, D.; Wooden, J.; O'Sullivan, P.; Argent, J.; Fanning, C.

    2000-01-01

    Thermochronologic and thermobarometric data reveal the timing, distribution and intensity of thermal events associated with detachment faulting in the Sacramento Mountains metamorphic core complex. In the northwest Sacramento Mountains, cooling rates of c. 100°C Ma−1 are associated with Late Cretaceous plutonism followed by cooling of the crust by thermal conduction. Post-Late Cretaceous cooling slowed to c. 1–6°C Ma−1. Finally, the region records average cooling rates of 38–53°C Ma−1 between c. 20 and 15 Ma. In contrast, the thermal profile of the northeast Sacramento Mountains is dominated by syntectonic Tertiary plutonism followed by very rapid cooling. A granodioritic suite intruded at c. 680°C and c. 3 kbar at c. 20 Ma, records cooling to <100°C by c. 15 Ma. Such rapid cooling and exhumation suggests that unroofing by tectonic denudation was the driving mechanism for the final cooling. The similarity of the miocene cooling profiles between these two areas clearly suggests that the Sacramento Mountains experienced a regional cooling event associated with tectonic unroofing driven by regional Miocene crustal extension. Estimates of the initial angle of the Sacramento Mountains detachment fault using palaeothermal gradients suggest that it was active at a dip of 25°.

  5. [The abundance and distribution of the Ixodes persulcatus (Acari: Ixodidae) near its northern spreading limit in the Ural Mountains].

    PubMed

    Livanova, N N; Livanov, S G

    2006-01-01

    A count of the tick species Ixodes persulcatus Schulze, 1930 was carried out in the "Denezhkin Kamen" Nature Reserve and adjacent territories (the Severoural'sk and Ivdel' Districts of the Sverdlovsk Region, the Northern Urals geographical province) in the 2005. The abundance and distribution of unengorged adults has been evaluated on an area of 22.5 square kilometers (N 60 degrees 27'-60 degrees 30' E 059 degrees 38'-059 degrees 42'). The area includes proportionally main landscape and vegetation elements of the region studied, from mountain analogues of the middle and northern taiga up to tundra. One tick species, I. persulcatus, has been collected by flagging with the abundance from 0.4 up to 6.8 (average 1.6 +/- 0.9) specimens per flag-hour. The observed values of abundance are classified into three classes (I - ticks are absent, II - 1-2 specimens, and III - 3-7 specimens per flag-hour). The class I amounts 20, II - 75, and III - 5% of the area examined. It has been revealed by the expert evaluation of the 2003-2004 and counts of the 2005 that ticks occur stably in the Northern Ural, reaching N 61 degrees and 400 m above sea level. The level of the species abundance remained constant till the middle of summer. In this period the activity of ticks dependent on the weather optimum only. PMID:17042282

  6. Quaternary glacial geomorphosites from the Cantabrian Mountains (northern Iberian Peninsula): the Redes Natural Reservation and Picos de Europa Regional Park

    NASA Astrophysics Data System (ADS)

    Rodríguez-Rodríguez, Laura; Jiménez-Sánchez, Montserrat; José Domínguez-Cuesta, María

    2013-04-01

    the Quaternary glaciations, especially after the last local glacial maximum. Jiménez-Sánchez, M., Rodríguez-Rodríguez, L., García-Ruiz, J.M., Domínguez-Cuesta, M.J., Farias, P., Valero-Garcés, B., Moreno, A., Rico, M., Valcárcel, M., in press. A review of glacial geomorphology and chronology in northern Spain: timing and regional variability during the last glacial cycle. Geomorphology, doi: 10.1016/j.geomorph.2012.06.009. Serrano, E., González-Trueba, J.J., Pellitero, R., González-García, M., Gómez-Lende, M., in press. Quaternary glacial evolution in the Central Cantabrian Mountains (Northern Spain). Geomorphology, doi:10.1016/j.geomorph.2012.05.001. Research funded by the project CANDELA (CGL2012-31938) of the Spanish national research program in Earth Sciences and Hydric Resources (MICINN) and the project FC-11-PC-10-14 (FICYT-Asturias). L. Rodríguez-Rodríguez has developed her research under a grant of the Severo Ochoa Program (FICYT- Asturias).

  7. Enhanced sediment delivery in a changing climate in semi-arid mountain basins: Implications for water resource management and aquatic habitat in the northern Rocky Mountains

    NASA Astrophysics Data System (ADS)

    Goode, Jaime R.; Luce, Charles H.; Buffington, John M.

    2012-02-01

    The delivery and transport of sediment through mountain rivers affects aquatic habitat and water resource infrastructure. While climate change is widely expected to produce significant changes in hydrology and stream temperature, the effects of climate change on sediment yield have received less attention. In the northern Rocky Mountains, we expect climate change to increase sediment yield primarily through changes in temperature and hydrology that promote vegetation disturbances (i.e., wildfire, insect/pathogen outbreak, drought-related die off). Here, we synthesize existing data from central Idaho to explore (1) how sediment yields are likely to respond to climate change in semi-arid basins influenced by wildfire, (2) the potential consequences for aquatic habitat and water resource infrastructure, and (3) prospects for mitigating sediment yields in forest basins. Recent climate-driven increases in the severity and extent of wildfire suggest that basin-scale sediment yields within the next few years to decades could be greater than the long-term average rate of 146 T km - 2 year - 1 observed for central Idaho. These elevated sediment yields will likely impact downstream reservoirs, which were designed under conditions of historically lower sediment yield. Episodic erosional events (massive debris flows) that dominate post-fire sediment yields are impractical to mitigate, leaving road restoration as the most viable management opportunity for offsetting climate-related increases in sediment yield. However, short-term sediment yields from experimental basins with roads are three orders of magnitude smaller than those from individual fire-related events (on the order of 10 1 T km - 2 year - 1 compared to 10 4 T km - 2 year - 1 , respectively, for similar contributing areas), suggesting that road restoration would provide a relatively minor reduction in sediment loads at the basin-scale. Nevertheless, the ecologically damaging effects of fine sediment (material < 6 mm

  8. Hydrology of area 58, northern Great Plains and Rocky Mountain coal provinces, Colorado and Utah

    SciTech Connect

    Chaney, T.H.; Kuhn, G.; Brooks, T.

    1987-01-01

    The topics encompass the complete physical and hydrologic setting of Area 58, located primarily in west-central Colorado in the Southern Rocky Mountain and Colorado Plateau physiographic provinces. The headwaters of the Colorado and most of its tributaries originate in the mountains forming the eastern boundary of the area. Precipitation in the mountains can exceed 40 in annually, most of it as snow. Most of the runoff then is a result of snow melting in the spring. Surface water is the principal source of water supplies in the area, and irrigation is the major water use. Groundwater supplies are mainly from wells completed in alluvium or fractured bedrock. All coal mines in the basin but one are underground. Surface water quality is best in the mountains. Dissolved solids concentrations in the Colorado River increase an average of 647 mg/L as it flows through the area. The causes of this increase are nearly equally divided between natural sources and irrigation activities in the sedimentary basins. The climate in these basins is semi-arid, and the soils are not adequately leached. Concentrations of several major elements and trace elements in the groundwater can be large enough to limit water uses. Among those elements exceeding recommended or required standards for use are calcium, chromium, iron, manganese, and lead. 166 refs., 39 figs., 2 tabs.

  9. Conservation assessment for the Siskiyou Mountains salamander and Scott Bar salamander in northern California.

    SciTech Connect

    Vinikour, W. S.; LaGory, K. E.; Adduci, J. J.; Environmental Science Division

    2006-10-20

    The purpose of this conservation assessment is to summarize existing knowledge regarding the biology and ecology of the Siskiyou Mountains salamander and Scott Bar salamander, identify threats to the two species, and identify conservation considerations to aid federal management for persistence of the species. The conservation assessment will serve as the basis for a conservation strategy for the species.

  10. Paleoenvironment of the Permian rocks: a comparison between central and eastern Alborz, Iran

    NASA Astrophysics Data System (ADS)

    Lankarani, M.; Amini, A.; Mosadegh, H.

    2009-04-01

    The succession of Permian rocks in Alborz region is composed of siliciclastic and carbonate facies. All of the sediments were deposited in the Paleotethyan passive continental margin but they show different facies architecture and paleoenvironmental condition in various parts of the region. This study, as part of a wider project, has investigated sedimentary facies and paleoenvironment of the Permian rocks in central and eastern Alborz. The Permian rocks in central Alborz are dominated by siliciclastic facies (Doroud Formation) in the lower, and carbonate facies (Ruteh Formation) in the upper half. Field studies and laboratory measurements resulted in recognition of 4 terrigenous and 13 carbonate facies in the succession. A siliciclastic shallow marine system was determined as depositional environment of the terrigenous facies. A homoclinal carbonate ramp, with scattered patch reefs, was determined as depositional environment of the carbonate facies. Dasycladacean green algae, ancestral red algae, hermatypic corals and bryozoans were the major bioconstructors of the ramp. The abundance of skeletal shoals respect to ooidal shoals in the ramp margin was high. The Permian rocks in eastern Alborz are dominated by mixed siliciclastic-carbonate facies (Ruteh Formation) in the lower, and siliciclastic facies (Nesen Formation) in the upper half. The studies resulted in recognition of 5 terrigenous and 6 carbonate facies in the succession. A mixed siliciclastic-carbonate shelf with high sediment influx was determined as depositional environment of the mixed siliciclastic-carbonate facies. Occurrence of the small patch reefs with high coral diversity in this mixed shelf indicates normal marine (hyposaline) condition. Upper terrigenous facies were deposited in fluvial-flood plain system. Difference in paleoclimate and tectonic activity of two sub-basins seems to be the major cause of the differences between the Permian facies in central and eastern Alborz.

  11. 1999 resource assessment of selected Tertiary coal beds and zones in the Northern Rocky Mountains and Great Plains region

    USGS Publications Warehouse

    Fort Union Coal Assessment Team

    1999-01-01

    The USGS has assessed resources of selected coal of the Fort Union Formation and equivalent units in the Northern Rocky Mountains and Great Plains region. The assessment focused on coal in the Powder River, Williston, Hanna-Carbon, and Greater Green River basins most likely to be utilized in the next few decades. In other basins in the region Tertiary coal resources are summarized but not assessed. Disc 1, in PDF files, includes results of the assessment and chapters on coal geology, quantity and quality, and land use and ownership. Disc 2 provides GIS files for land use and ownership maps and geologic maps, and basic GIS data for the assessed basins. ArcView shapefiles, PDF files for cross sections and TIFF files are included along with ArcView Datapublisher software for Windows-based computer systems.

  12. Evolution of the northern santa cruz mountains by advection of crust past a san andreas fault bend.

    PubMed

    Anderson, R S

    1990-07-27

    The late Quaternary marine terraces near Santa Cruz, California, reflect uplift associated with the nearby restraining bend on the San Andreas fault. Excellent correspondence of the coseismic vertical displacement field caused by the 17 October 1989 magnitude 7.1 Loma Prieta earthquake and the present elevations of these terraces allows calculation of maximum long-term uplift rates 1 to 2 kilometers west of the San Andreas fault of 0.8 millimeters per year. Over several million years, this uplift, in concert with the right lateral translation of the resulting topography, and with continual attack by geomorphic processes, can account for the general topography of the northern Santa Cruz Mountains. PMID:17755944

  13. Conodont and Radiolarian Data from the De Long Mountains Quadrangle and Adjacent Areas, Northern Alaska

    USGS Publications Warehouse

    Dumoulin, Julie A.; Harris, Anita G.; Blome, Charles D.; Young, Lorne E.

    2006-01-01

    INTRODUCTION This report presents biostratigraphic data from 289 collections at 189 localities in the De Long Mountains, Misheguk Mountain, and Noatak quadrangles (fig. 1); most of these data have never been previously published. The collections were made during studies of the Red Dog massive sulfide deposit in 1998?2004 and in support of regional mapping projects in 1979, 1981, 1983, and 1997?98. The collections?mostly conodonts and some radiolarians?tightly constrain the age of many stratigraphic units of Devonian through Triassic age exposed within the study area, and provide additional data on the depositional environments and thermal history of these rocks. The data are presented in a series of tables, organized by fossil type, stratigraphic unit, and location. Tables 1?12 contain conodont data, mostly from the De Long Mountains quadrangle. All of these collections were initially examined, or were reevaluated, from 1997 through 2004, and complete faunal lists are given for all samples. Table 13 lists ages and conodont color alteration indices (CAIs) of 27 collections from 24 localities in the Noatak quadrangle; updated faunal lists were not prepared for these samples. Radiolarian data?all from the De Long Mountains quadrangle?are given in table 14; these collections were analyzed between 1998 and 2003. Collection localities are shown in four maps (sheets 1, 2). Map 1 (sheet 1) shows all outcrop samples from the De Long Mountains and western Misheguk Mountain quadrangle (locs. 1-121). Maps 2?4 (sheets 1, 2) show all drill hole sample localities; samples come from the Su-Lik deposit and in and around the Anarraaq deposit (map 2, locs. 122?135), in and adjacent to the Red Dog deposits (Paalaaq, Aqqaluk, Main, and Qanaiyaq) (map 3, locs. 136?158), and from drill holes along the Port Road in the Noatak quadrangle (map 4, locs. 159?160). Map 4 (sheet 2) also shows all outcrop samples from the Noatak quadrangle (locs. 161?189). The text summarizes the lithofacies

  14. The post-Fusselman karst of the northern Franklin Mountains, west Texas and south-central New Mexico

    SciTech Connect

    Colleary, W.M. ); Crafton, J.W. Gas Research Institute, Chicago, IL ); Farraro, J.T.; LeMone, D.V. )

    1992-04-01

    The uppermost Fusselman Formation (Crazy Cat Member) at Anthony's Gap in the northern Franklin Mountains exhibits extensive karsting as documented by the presence of such features as sinkholes, breccia-filled solution channels, and preserved terra rosa. Karst control, post-El Paso as well as post-Fusselman, probably is developed by jointing resulting from recurrent fault movements in a pattern inherited from an ancestral Precambrian framework. The post-Fusselman karsting (Middle Silurian-Middle Devonian) in the Franklins developed over more than 40 m.y. The Fusselman represents the uppermost Tippecanoe sequence, and the disconformably overlying Canutillo Formation is the basal Kaskaskia in the Franklin Mountains. Overlying the Fusselman karst is a thin transgressive unit interpreted to be a silicified lag deposit. The unit has been observed to be only sporadically deposited in local swales and reaches a maximum thickness on the order of 30 cm. This dark-brown to black unit contains subrounded dolomitic pebbles of the Fusselman, as well as scattered fossil material, which in the vertebrates includes apparent teeth and bone material. This lag deposit is interpreted to represent an initial transgressive or flooding surface. This deposit has produced a significant radioactive 'hot' gamma-ray spike in a profile taken through the formation using a hand-held scintillometer. The top of the Fusselman in the Permian basin typically is marked on subsurface well logs by a 'hot' gamma-ray spike.

  15. Glacier change from the early Little Ice Age to 2005 in the Torngat Mountains, northern Labrador, Canada

    NASA Astrophysics Data System (ADS)

    Way, Robert G.; Bell, Trevor; Barrand, Nicholas E.

    2015-10-01

    The glaciers of the Torngat Mountains of northern Labrador are the southernmost of the Canadian Arctic and the easternmost of continental North America. Currently, 195 small mountain glaciers cover an area in excess of ~ 24 km2, confined mostly to small cirques and upland depressions. Using a combination of field and remote sensing methods this study reconstructs and dates the areal extent of Torngat glaciers at their Neoglacial maximums, enabling the first assessment of regional glacier change over the past several centuries. Mapped glacier paleomargins (n = 165) are compared to current (2005) glaciers and ice masses, showing a 52.5% reduction in glacier area, with at least 11 former glaciers altogether disappearing. Glacier change is spatially homogenous and independent of most geographic and topographic factors; however, glacier elevation and glacier size mitigated total change. Previously established lichen growth stations were revisited, and growth rates recalculated based on ~ 30-year-long records, enabling the construction of locally derived low- and high-altitude lichen growth curves. Using growth rates and in situ lichen measurements, the retreat from maximum Neoglacial moraine extents are suggested to have occurred between A.D. 1581 and 1673. These findings indicate a similar magnitude of post-LIA retreat to mountain glaciers elsewhere, yet a much earlier timing (~ 200 years) of retreat than other glaciers in the eastern Canadian Arctic. Though no definitive answer explaining this discrepancy is presented, evidence suggests that regional climate dynamics and the importance of solar radiation for Torngat glaciers may play an important role in local glacierization.

  16. Isotope geochemistry of thermal and nonthermal waters in the Valles caldera, Jemez Mountains, northern New Mexico

    SciTech Connect

    Vuataz, F.D.; Goff, F.

    1986-02-10

    Over 100 stable isotope and 45 tritium analyses from thermal and nonthermal waters of the Jemez Mountains region, New Mexico, have been used to define the hydrodynamics of the Valles caldera (Baca) geothermal system and related geothermal fluids of the region. Evaluation of 36 cold meteoric waters yields an equation for the Jemez Mountains meteoric water line of deltaD = 8delta/sup 18/O+12, while further evaluation of nine cold meteoric waters yields an equation relating recharge elevation to deuterium content of E(meters) = -44.9 (deltaD)-1154. Based on the deuterium content of five Baca well waters (223/sup 0/--294/sup 0/C), the average recharge elevation of the Valles geothermal system ranges from 2530 to 2890 m. This range of elevations falls between the elevations of the lowest point of the caldera floor (2400 m) and the summit of the resurgent dome inside the caldera (3430 m). Thus stable isotopes indicate that the caldera depression probably serves as a recharge basin for the deep geothermal system. Although cold spring waters of the Jemez Mountains region consist of meteoric water, tritium analyses show that most of them contain water between 20 and 75 years old.

  17. Mountain Roads, Lonely Mesas: A Career Program for Northern New Mexico.

    ERIC Educational Resources Information Center

    Strong, Kathryn Ringhand

    Educational outreach programs of Los Alamos National Laboratory assist rural educators in strengthening science curricula; encourage students to take science, math, and English courses; and create a good neighbor policy between the laboratory and rural communities/schools in predominantly Hispanic/American Indian northern New Mexico. The program,…

  18. Bouguer gravity trends and crustal structure of the Palmyride Mountain belt and surrounding northern Arabian platform in Syria

    SciTech Connect

    Best, J.A.; Barazangi, M. ); Al-Saad, D.; Sawaf, T.; Gebran, A. )

    1990-12-01

    This study examines the crustal structure of the Palmyrides and the northern Arabian platform in Syria by two- and three-dimensional modeling of the Bouguer gravity anomalies. Results of the gravity modeling indicate that (1) western Syria is composed of at least two different crustal blocks, (2) the southern crustal block is penetrated by a series of crustal-scale, high-density intrusive complexes, and (3) short-wavelength gravity anomalies in the southwest part of the mountain belt are clearly related to basement structure. The crustal thickness in Syria, as modeled on the gravity profiles, is approximately 40{plus minus}4 km, which is similar to crustal thicknesses interpreted from refraction data in Jordan and Saudi Arabia. The different crustal blocks and large-scale mafic intrusions are best explained, though not uniquely, by Proterozoic convergence and suturing and early Paleozoic rifting, as interpreted in the exposed rocks of the Arabian shield. These two processes, combined with documented Mesozoic rifting and Cenozoic transpression, compose the crustal evolution of the northern Arabian platform beneath Syria.

  19. Determinants of peak discharge in steep mountain catchments - Case of the Rift Valley escarpment of Northern Ethiopia

    NASA Astrophysics Data System (ADS)

    Asfaha, Tesfaalem G.; Frankl, Amaury; Haile, Mitiku; Zenebe, Amanuel; Nyssen, Jan

    2015-10-01

    Peak discharge is an important hydrological parameter of mountain torrents. However, due to the flashy and destructive nature of their stream flows, it is usually difficult to understand the hydrological behavior of steep mountain catchments through direct measurements of discharges. In this study, 332 daily peak discharge events from 11 steep (0.27-0.65 m m-1) catchments (0.4-25 km2) were measured in three rainy seasons (2012-2014) with the objective of analyzing runoff response of steep mountain catchments in the western Rift Valley escarpment of Northern Ethiopia. Seven rain gauges were installed at different altitudes (1623-2851 m a.s.l.) in and nearby the catchments. Event peak discharges were calculated using the Manning's equation from daily measurements of maximum discharge height at 11 crest stage gauges. Percentages of land cover classes were detected from high resolution (0.6 m) Google Earth Imagery (February 1, 2014). Morphometric characteristics of the catchments were computed both from ASTER digital elevation model (DEM) and topographic maps. Correlation analysis between average daily precipitation (Pd) and peak discharge (Qp) showed strong positive relation (R2 = 0.32-0.94, P < 0.05) in all the catchments. Catchment-specific peak discharge coefficient (Cp) showed a strong decreasing relation with vegetation cover (R2 = 0.85, P < 0.01), relative distance of vegetation cover from the thalweg (R2 = 0.55, P < 0.01), combined index of vegetation cover and its relative distance from the thalweg (R2 = 0.76, P < 0.01), catchment length (R2 = 0.37, P < 0.05) and time of concentration (R2 = 0.43, P < 0.05). It was correlated positively with catchment slope gradient (R2 = 0.37, P < 0.05) and index of vegetation distribution (R2 = 0.45, P < 0.05). A stepwise multiple regression analysis revealed that 99% (P < 0.01) of the variability of catchment-specific peak discharge coefficient in the catchments can be predicted by vegetation cover and infiltration number

  20. Seismic study of the crust beneath the Northern Mountains from Receiver Function analysis

    NASA Astrophysics Data System (ADS)

    Ben Mansour, Walid; England, Richard; Moorkamp, Max

    2015-04-01

    The analysis of P receiver functions is rapidly becoming a classical technique for study of the crust beneath seismic stations from seismic arrays. This approach is based on the simple assumption of 1D horizontal layers. If the resolution depends on the inter-station distance and the noise level, we can extract easily the Ps conversion from the Moho beneath the station by picking the spike around +/-5 s after the direct P wave. Knowing the delay between the Ps conversion and the direct P wave and assuming a relative Vp we can quantify the Moho depth and the Vp/Vs ratio. We have applied this approach in a noisy environment (Scandinavia) using 2 temporary broadband (SCANLIPS2 and SCANLIPS3D) arrays in order to have a better idea of the Moho geometry across the Scandinavian Mountains. This mountain range is a topographic anomaly (peaks above 1 km) close to the flat region of the Baltic shield (maximum height 500 m above sea level). The classical techniques such as H-k stacking and the CCP depth migration have been used to image the crustal structure. Our results show a crustal thickening from West to East (40 km to 50 km) without an associated change in surface or Moho topography. These results suggest that the Scandinavia Mountains will not be supported by a crustal root like that seen beneath young mountain ranges such as the Alps or Himalaya. Our inverse modelling cannot confirm the presence of a low velocity zone in the upper crust suggested previous works in the area using P receiver functions and controlled souce seismology. We suggest a new 2D crustal model (H, Vs) across the range. Nevertheless, the uncertainty on the Vp/Vs ratio under the some stations due to very weak PpS phase is an issue for the interpretation of our results. Indeed without extra information we have used a Vp/Vs ratio for the crust of 1.73 in the modelling of receiver functions. From the H-K stacking we have a variability of Vp/Vs ratio from 1.74 to 2.0-which is not consistent with the

  1. Population data on nine STRs from Cantabria, a mountainous region in northern Spain.

    PubMed

    Zarrabeitia, M T; Riancho, J A

    2001-11-01

    Allele frequencies for nine STRs loci included in the AmpFlTR Profiler Plus kit (D3S1358, vWA, FGA, D8S1179, D21S11, D18S51, D5S818, D13S317, D7S820) were obtained from a sample of 158 unrelated individuals living in Cantabria, a region in northern Spain. PMID:11672975

  2. Spatial and temporal controls on watershed ecohydrology in the northern Rocky Mountains

    NASA Astrophysics Data System (ADS)

    Emanuel, Ryan E.; Epstein, Howard E.; McGlynn, Brian L.; Welsch, Daniel L.; Muth, Daniel J.; D'Odorico, Paolo

    2010-11-01

    Vegetation water stress plays an important role in the movement of water through the soil-plant-atmosphere continuum. However, the effects of water stress on evapotranspiration (ET) and other hydrological processes at the watershed scale remain poorly understood due in part to spatially and temporally heterogeneous conditions within the watershed, especially in areas of mountainous terrain. We used a spatially distributed model to understand and evaluate the relationship between water stress and ET in a forested mountain watershed during the snow-free growing season. Vegetation water stress increased as the growing season progressed, due to continued drying of soils, and persisted late into the growing season, even as vapor pressure deficit decreased with lower temperatures. As a result, ET became decoupled from vapor pressure deficit and became increasingly dependent on soil moisture later in the growing season, shifting from demand limitation to supply limitation. We found water stress and total growing season ET to be distributed nonuniformly across the watershed due to interactions between topography and vegetation. Areas having tall vegetation and low topographic index experienced the greatest water stress, yet they had some of the highest evapotranspiration rates in the watershed.

  3. Paleomagnetic results from the Shasta Bally Plutonic Belt in the Klamath Mountains Province, northern California

    NASA Astrophysics Data System (ADS)

    Mankinen, Edward A.; Irwin, William P.; Grommé, C. Sherman

    1988-01-01

    Available paleomagnetic data show approximately 100° of clockwise rotation for Permian and Triassic strata of the Eastern Klamath terrane. Jurassic strata of this terrane are rotated approximately 60° clockwise, which is comparable to rotations reported for Jurassic plutons that occur elsewhere in the Klamath Mountains province. Paleomagnetic data obtained during the present study from the Shasta Bally belt of Cretaceous plutons indicate 25.7° ± 13.6° of clockwise rotation for the province since Early Cretaceous time (≃ 136 Ma). The waning stages of rotation at the time of emplacement of the Shasta Bally belt plutons, which was closely followed by deposition of basal strata (Lower Cretaceous) of the Great Valley sequence, probably represents completion of accretion of the province to cratonic North America.

  4. Hydrology of Area 62, Northern Great Plains and Rocky Mountain Coal Provinces, New Mexico and Arizona

    USGS Publications Warehouse

    Roybal, F.E.; Wells, J.G.; Gold, R.L.; Flager, J.V.

    1984-01-01

    This report summarizes available hydrologic data for Area 62 and will aid leasing decisions, and the preparation and appraisal of environmental impact studies and mine-permit applications. Area 62 is located at the southern end of the Rocky Mountain Coal Province in parts of New Mexico and Arizona and includes approximately 9,500 square miles. Surface mining alters, at least temporarily, the environment; if the areas are unreclaimed, there can be long-term environmental consequences. The land-ownership pattern in Area 62 is complicated. The checkerboard pattern created by several types of ownership makes effective management of these lands difficult. The climate generally is semiarid with average annual precipitation ranging from 10 to 20 inches. Pinons, junipers, and grasslands cover most of the area, and much of it is used for grazing by livestock. Soils vary with landscape, differing from flood plains and hillslopes to mountain slopes. The major structural features of this area were largely developed during middle Tertiary time. The main structural features are the southern San Juan Basin and the Mogollon slope. Coal-bearing rocks are present in four Cretaceous rock units of the Mesaverde Group: the Gallup Sandstone, the Dileo Coal Member, and the Gibson Coal Member of the Crevasse Canyon Formation, and the Cleary Coal Member of the Menefee Formation. Area 62 is drained by Black Creek, the Puerco River, the Zuni River, Carrizo Wash-Largo Creek, and the Rio San Jose. Only at the headwaters of the Zuni River is the flow perennial. The streamflow-gaging station network consists of 25 stations operated for a variety of needs. Streamflow changes throughout the year with variation related directly to rainfall and snowmelt. Base flow in Area 62 is zero indicating no significant ground-water discharge. Mountainous areas contribute the highest mean annual runoff of 1.0 inch. Very few water-quality data are available for the surface-water stations. Of the nine surface

  5. Mesozoic petrotectonic development of the Sawyers Bar suprasubduction-zone arc, central Klamath Mountains, northern California

    SciTech Connect

    Ernst, W.G.

    1999-08-01

    The Sawyers Bar area of the central Klamath Mountains, California, consists of three tectonically juxtaposed supracrustal units: (1) on the east, the Stuart Fork metabasalt-metachert-metagraywacke terrane above the low-angle, east-dipping Soap Creek Ridge thrust; (2) the medial North Fork ophiolitic terrane, composed of intercalated St. Clair Creek laminated cherts and fine-grained quartzofeldspathic argillites, interstratified with and overlain by two mafic igneous, largely extrusive suites--North Fork (sensu stricto) mildly alkaline basalts, and Salmon River basaltic-diabasic-gabbroic arc tholeiites; and (3) the cherty, Eastern Hayfork metagraywacke melange terrane west of the minor, high-angle Twin Sisters fault. Mineral and bulk-rich elemental and isotopic data, integrated with geologic mapping, document deformation and fluid-rock interaction in the upper few kilometers of a suprasubduction-zone basaltic arc during tectonic accretion to the western margin of North America or a nearby offshore arc. The geologic history is advanced.

  6. Combustion efficiency and emission factors for wildfire-season fires in mixed conifer forests of the northern Rocky Mountains, US

    NASA Astrophysics Data System (ADS)

    Urbanski, S. P.

    2013-07-01

    In the US, wildfires and prescribed burning present significant challenges to air regulatory agencies attempting to achieve and maintain compliance with air quality regulations. Fire emission factors (EF) are essential input for the emission models used to develop wildland fire emission inventories. Most previous studies quantifying wildland fire EF of temperate ecosystems have focused on emissions from prescribed burning conducted outside of the wildfire season. Little information is available on EF for wildfires in temperate forests of the conterminous US. The goal of this work is to provide information on emissions from wildfire-season forest fires in the northern Rocky Mountains, US. In August 2011, we deployed airborne chemistry instruments and sampled emissions over eight days from three wildfires and a prescribed fire that occurred in mixed conifer forests of the northern Rocky Mountains. We measured the combustion efficiency, quantified as the modified combustion efficiency (MCE), and EF for CO2, CO, and CH4. Our study average values for MCE, EFCO2, EFCO, and EFCH4 were 0.883, 1596 g kg-1, 135 g kg-1, 7.30 g kg-1, respectively. Compared with previous field studies of prescribed fires in temperate forests, the fires sampled in our study had significantly lower MCE and EFCO2 and significantly higher EFCO and EFCH4. The fires sampled in this study burned in areas reported to have moderate to heavy components of standing dead trees and down dead wood due to insect activity and previous fire, but fuel consumption data was not available. However, an analysis of MCE and fuel consumption data from 18 prescribed fires reported in the literature indicates that the availability of coarse fuels and conditions favorable for the combustion of these fuels favors low MCE fires. This analysis suggests that fuel composition was an important factor contributing to the low MCE of the fires measured in this study. This study only measured EF for CO2, CO, and CH4; however, we

  7. Altitudinal Patterns of Species Diversity and Phylogenetic Diversity across Temperate Mountain Forests of Northern China.

    PubMed

    Zhang, Wenxin; Huang, Dizhou; Wang, Renqing; Liu, Jian; Du, Ning

    2016-01-01

    The spatial patterns of biodiversity and their underlying mechanisms have been an active area of research for a long time. In this study, a total of 63 samples (20m × 30m) were systematically established along elevation gradients on Mount Tai and Mount Lao, China. We explored altitudinal patterns of plant diversity in the two mountain systems. In order to understand the mechanisms driving current diversity patterns, we used phylogenetic approaches to detect the spatial patterns of phylogenetic diversity and phylogenetic structure along two elevation gradients. We found that total species richness had a monotonically decreasing pattern and tree richness had a unimodal pattern along the elevation gradients in the two study areas. However, altitudinal patterns in shrub richness and herbs richness were not consistent on the two mountains. At low elevation, anthropogenic disturbances contributed to the increase of plant diversity, especially for shrubs and herbs in understory layers, which are more sensitive to changes in microenvironment. The phylogenetic structure of plant communities exhibited an inverted hump-shaped pattern along the elevation gradient on Mount Tai, which demonstrates that environmental filtering is the main driver of plant community assembly at high and low elevations and inter-specific competition may be the main driver of plant community assembly in the middle elevations. However, the phylogenetic structure of plant communities did not display a clear pattern on Mount Lao where the climate is milder. Phylogenetic beta diversity and species beta diversity consistently increased with increasing altitudinal divergence in the two study areas. However, the altitudinal patterns of species richness did not completely mirror phylogenetic diversity patterns. Conservation areas should be selected taking into consideration the preservation of high species richness, while maximizing phylogenetic diversity to improve the potential for diversification in the

  8. Altitudinal Patterns of Species Diversity and Phylogenetic Diversity across Temperate Mountain Forests of Northern China

    PubMed Central

    Zhang, Wenxin; Huang, Dizhou; Wang, Renqing; Liu, Jian; Du, Ning

    2016-01-01

    The spatial patterns of biodiversity and their underlying mechanisms have been an active area of research for a long time. In this study, a total of 63 samples (20m × 30m) were systematically established along elevation gradients on Mount Tai and Mount Lao, China. We explored altitudinal patterns of plant diversity in the two mountain systems. In order to understand the mechanisms driving current diversity patterns, we used phylogenetic approaches to detect the spatial patterns of phylogenetic diversity and phylogenetic structure along two elevation gradients. We found that total species richness had a monotonically decreasing pattern and tree richness had a unimodal pattern along the elevation gradients in the two study areas. However, altitudinal patterns in shrub richness and herbs richness were not consistent on the two mountains. At low elevation, anthropogenic disturbances contributed to the increase of plant diversity, especially for shrubs and herbs in understory layers, which are more sensitive to changes in microenvironment. The phylogenetic structure of plant communities exhibited an inverted hump-shaped pattern along the elevation gradient on Mount Tai, which demonstrates that environmental filtering is the main driver of plant community assembly at high and low elevations and inter-specific competition may be the main driver of plant community assembly in the middle elevations. However, the phylogenetic structure of plant communities did not display a clear pattern on Mount Lao where the climate is milder. Phylogenetic beta diversity and species beta diversity consistently increased with increasing altitudinal divergence in the two study areas. However, the altitudinal patterns of species richness did not completely mirror phylogenetic diversity patterns. Conservation areas should be selected taking into consideration the preservation of high species richness, while maximizing phylogenetic diversity to improve the potential for diversification in the

  9. Cross-Scale Analysis of the Region Effect on Vascular Plant Species Diversity in Southern and Northern European Mountain Ranges

    PubMed Central

    Lenoir, Jonathan; Gégout, Jean-Claude; Guisan, Antoine; Vittoz, Pascal; Wohlgemuth, Thomas; Zimmermann, Niklaus E.; Dullinger, Stefan; Pauli, Harald; Willner, Wolfgang; Grytnes, John-Arvid; Virtanen, Risto; Svenning, Jens-Christian

    2010-01-01

    Background The divergent glacial histories of southern and northern Europe affect present-day species diversity at coarse-grained scales in these two regions, but do these effects also penetrate to the more fine-grained scales of local communities? Methodology/Principal Findings We carried out a cross-scale analysis to address this question for vascular plants in two mountain regions, the Alps in southern Europe and the Scandes in northern Europe, using environmentally paired vegetation plots in the two regions (n = 403 in each region) to quantify four diversity components: (i) total number of species occurring in a region (total γ-diversity), (ii) number of species that could occur in a target plot after environmental filtering (habitat-specific γ-diversity), (iii) pair-wise species compositional turnover between plots (plot-to-plot β-diversity) and (iv) number of species present per plot (plot α-diversity). We found strong region effects on total γ-diversity, habitat-specific γ-diversity and plot-to-plot β-diversity, with a greater diversity in the Alps even towards distances smaller than 50 m between plots. In contrast, there was a slightly greater plot α-diversity in the Scandes, but with a tendency towards contrasting region effects on high and low soil-acidity plots. Conclusions/Significance We conclude that there are strong regional differences between coarse-grained (landscape- to regional-scale) diversity components of the flora in the Alps and the Scandes mountain ranges, but that these differences do not necessarily penetrate to the finest-grained (plot-scale) diversity component, at least not on acidic soils. Our findings are consistent with the contrasting regional Quaternary histories, but we also consider alternative explanatory models. Notably, ecological sorting and habitat connectivity may play a role in the unexpected limited or reversed region effect on plot α-diversity, and may also affect the larger-scale diversity components. For

  10. Visceral Leishmaniasis in Rural Areas of Alborz Province of Iran and Implication to Health Policy

    PubMed Central

    Heidari, Aliehsan; Mohebali, Mehdi; Kabir, Kourosh; Barati, Hojatallah; Soultani, Yousef; Keshavarz, Hossein; Akhoundi, Behnaz; Hajjaran, Homa; Reisi, Hosein

    2015-01-01

    Visceral leishmaniasis (VL) or kala-azar mainly affects children in endemic areas. This study was conducted to determine the seroprevalence of VL using direct agglutination test (DAT) in children living in rural districts of Alborz Province located 30 km from Tehran capital city of Iran. Multi-stage cluster random sampling was applied. Blood samples were randomly collected from 1,007 children under 10 years of age in the clusters. A total of 37 (3.7%) of the studied population showed anti-Leishmania infantum antibodies with titers of ≥1:800. There was a significant association between positive sera and various parts of the rural areas of Alborz Province (P<0.002). Two children with anti-Leishmania infantum antibodies titers of ≥1:3,200 indicated kala-azar clinical features and treated with anti-leishmaniasis drugs in pediatric hospital. The findings of this study indicated that Leishmania infection is prevalent in rural areas of Alborz Province. Therefore, it is necessary to increase the awareness and alertness among physicians and public health managers, particularly in high-risk rural areas of the province in Iran. PMID:26323835

  11. Size-resolved aerosol trace elements at a rural mountainous site in Northern China: importance of regional transport.

    PubMed

    Pan, Yuepeng; Wang, Yuesi; Sun, Yang; Tian, Shili; Cheng, Mengtian

    2013-09-01

    This paper presents an intensive field measurement campaign carried out at the rural mountainous site of Xinglong (960 m a.s.l.) in Northern China during Sep. 3-20 2008. Size-segregated samples were collected daily and analyzed for 25 trace elements (TEs). The majority of the TEs showed comparable concentrations in fine (<2.1 μm) and coarse particles (2.1-9 μm). In addition, elements like K, Mn, Cu, Se, Mo, Ag, Cd, Tl and Pb were accumulated in fine mode whereas Al, Co and Sb were concentrated in a coarse mode. For most of the TEs, their enrichment factor (EF) increased with decreasing particle size from large (>9 μm) to coarse, and to fine, signifying influences by anthropogenic emissions. The observed concentrations of heavy metals in fine particles, with EF values higher than 100, were significantly higher than the historical data recorded in the 1980s and 1990s, reflecting the increasing emissions in the target area. One pronounced event occurred on Sep. 14 when all of the TEs showed a peak, which was associated with regional emissions from both southeast (SE) and southwest (SW) indicated by backward trajectory analysis. This is further supported by the measurements in upwind sites where the concentrations of TEs were several times higher than those in Xinglong, suggesting potential source regions. Episodes of heavy metals were generally characterized by significant enhancements of fine mode and air mass trajectories from SE or SW alone. Taking this finding and factor analysis results together, the metallic episodes were attributable to the long-range transport of regional plumes from coal consumption and nonferrous metal smelting. With the rapid urbanization and industrialization in Northern China, the increasing emissions of TEs will place a great strain on human health and the environment in the downwind regions, thus long-term and multi-site observation with high time resolution are necessary. PMID:23792621

  12. Comparison of changes in glacier area and thickness on the northern and southern slopes of Mt. Bogda, eastern Tianshan Mountains

    NASA Astrophysics Data System (ADS)

    Wang, Puyu; Li, Zhongqin; Wang, Wenbin; Li, Huilin; Wu, Lihua; Huai, Baojuan; Zhou, Ping; Jin, Shuang; Wang, Lin

    2016-09-01

    Rapid shrinkage and dramatic volume loss of the glaciers on Mt. Bogda in the eastern Tianshan Mountains have resulted in water shortages in the surrounding arid regions of China. Understanding ice thickness and its variation is important to the analysis of changes in glacial volume, which are directly related to regional hydrology and water resources. Fan-shaped Diffluence Glacier and Heigou Glacier No. 8 are located on the northern and southern slopes of Mt. Bogda, respectively. In this paper, the spatial distribution of the ice thickness of these two glaciers and the changes in their area and volume are discussed based on a 2009 survey result and comparison to previous investigations. The mean ice thickness of the tongue of Fan-shaped Diffluence Glacier was about 82.3 m and the calculated ice volume was 385.2 × 106 m3 in 2009. It had thinned by 14 ± 8 m (0.30 ± 0.17 m a- 1) from 1962 to 2009, equivalent to an ice volume loss of 65.5 ± 37.4 × 106 m3. The mean ice thickness of the tongue of Heigou Glacier No. 8 was 58.7 m and the calculated ice volume was 115.1 × 106 m3 in 2009. The tongue of Heigou Glacier No. 8 thinned by 13 ± 6 m (0.57 ± 0.26 m a- 1) from 1986 to 2009, which corresponds to an ice volume loss of 25.5 ± 11.8 × 106 m3. The greater thinning and retreat of Heigou Glacier No. 8 than those of Fan-shaped Diffluence Glacier is partially due to topographic characteristics. The difference can be attributed mainly to the greater increase in temperature on the southern slope than on the northern slope.

  13. Hydrology of area 53, Northern Great Plains and Rocky Mountain coal provinces, Colorado, Wyoming, and Utah

    USGS Publications Warehouse

    Driver, N.E.; Norris, J.M.; Kuhn, Gerhard; and others

    1984-01-01

    Hydrologic information and analysis are needed to aid in decisions to lease Federally owned coal and for the preparation of the necessary Environmental Assessments and Impact Study Reports. This need has become even more critical with the enactment of the Surface Mining Control and Reclamation Act of 1977 (Public Law 95-87). This report, one in a series of nationwide coal province reports, presents information thematically by describing single hydrologic topics through the use of brief texts and accompanying maps, graphs, or other illustrations. The report broadly characterizes the hydrology of Area 53 in northwestern Colorado, south-central Wyoming, and northeastern Utah. The report area, located primarily in the Wyoming Basin and Colorado Plateau physiographic provinces, consists of 14,650 square miles of diverse geology, topography, and climate. This diversity results in contrasting hydrologic characteristics. The two major rivers, the Yampa and the White Rivers, originate in humid granitic and basaltic mountains, then flow over sedimentary rocks underlying semiarid basins to their respective confluences with the Green River. Altitudes range from 4,800 to greater than 12,000 feet above sea level. Annual precipitation in the mountains, as much as 60 inches, is generally in the form of snow. Snowmelt produces most streamflow. Precipitation in the lower altitude sedimentary basins, ranging from 8 to 16 inches, is generally insufficient to sustain streamflow; therefore, most streams originating in the basins (where most of the streams in coal-mining areas originate) are ephemeral. Streamflow quality is best in the mountains where dissolved-solids concentrations generally are small. As streams flow across the sedimentary basins, mineral dissolution from the sedimentary rocks and irrigation water with high mineral content increase the dissolved-solids concentrations in a downstream direction. Due to the semiarid climate of the basins, soils are not adequately leached

  14. Permo-Triassic Accretionary Subduction Complex, southwestern Klamath Mountains, northern California

    NASA Astrophysics Data System (ADS)

    Wright, James E.

    1982-05-01

    The western Paleozoic and Triassic subprovince of the southwestern Klamath Mountains has previously been subdivided into three relatively steeply dipping, fault-bounded, litho-tectonic terranes. In descending structural order from east to west, these terranes are (1) the North Fork terrane, (2) the Hayfork terrane, and (3) the Rattlesnake Creek terrane. In a general fashion each of these terranes exhibits its own particular set of lithologic, structural, and temporal relationships that sets it apart from adjacent terranes. This threefold subdivision of the southwestern Klamath Mountains needs modification only as far as the Hayfork terrane is concerned. The Hayfork terrane is actually a composite terrane consisting of a structurally lower assemblage of predominantly basaltic metavolcaniclastic rocks and a structurally higher assemblage of chaotically disrupted metasedimentary rocks, juxtaposed along a previously unrecognized major regional thrust. These two lithologically and structurally distinct assemblages have been elevated to the status of a terrane in this report and are herein referred to as the western Hayfork terrane (structurally lower metavolcaniclastic assemblage) and the eastern Hayfork terrane (structurally overlying metasedimentary assemblage), and the fault which juxtaposes these two terranes is herein referred to as the Wilson Point thrust. This paper will focus on the eastern Hayfork and North Fork terranes and their relationship to other roughly coeval tectonic elements of the Klamath Mountain province. The eastern Hayfork terrane is best described as a tectono-stratigraphic unit consisting of a complex chert, argillite, and quartzose sandstone melange and broken formation that contains radiolarian cherts as young as Late Triassic in age. Scattered throughout this terrane are various types of blocks, some of which are clearly exotic. Metachert is by far the most common type of metamorphic block, and these blocks appear to have been derived via

  15. Impacts of conflict on land use and land cover in the Imatong Mountain region of South Sudan and northern Uganda

    NASA Astrophysics Data System (ADS)

    Gorsevski, Virginia B.

    The Imatong Mountain region of South Sudan makes up the northern most part of the Afromontane conservation 'biodiversity hotspot' due to the numerous species of plants and animals found here, some of which are endemic. At the same time, this area (including the nearby Dongotana Hills and the Agoro-Agu region of northern Uganda) has witnessed decades of armed conflict resulting from the Sudan Civil War and the presence of the Ugandan Lord's Resistance Army (LRA). The objective of my research was to investigate the impact of war on land use and land cover using a combination of satellite remote sensing data and semi-structured interviews with local informants. Specifically, I sought to (1) assess and compare changes in forest cover and location during both war and peace; (2) compare trends in fire activity with human population patterns; and (3) investigate the underlying causes influencing land use patterns related to war. I did this by using a Disturbance Index (DI), which isolates un-vegetated spectral signatures associated with deforestation, on Landsat TM and ETM+ data in order to compare changes in forest cover during conflict and post-conflict years, mapping the location and frequency of fires in subsets of the greater study area using MODIS active fire data, and by analyzing and summarizing information derived from interviews with key informants. I found that the rate of forest recovery was significantly higher than the rate of disturbance both during and after wartime in and around the Imatong Central Forest Reserve (ICFR) and that change in net forest cover remained largely unchanged for the two time periods. In contrast, the nearby Dongotana Hills experienced relatively high rates of disturbance during both periods; however, post war period losses were largely offset by gains in forest cover, potentially indicating opposing patterns in human population movements and land use activities within these two areas. For the Agoro-Agu Forest Reserve (AFR) region

  16. Changes in Physical and Chemical Soil Properties on Burnt Shrub Areas in Mediterranean Mountains, Northern Portugal

    NASA Astrophysics Data System (ADS)

    Fonseca, Felícia; de Figueiredo, Tomás; Leite, Micaela

    2014-05-01

    Human induced fire in scrublands to obtain better pastures for cattle is a relatively common practice in North Portugal. During burning, plant cover and litter layers are consumed, and the mineral soil is heated, resulting in changes to physical, chemical, mineralogical, and biological soil properties. Aiming at evaluating the effect of this kind of fires on a set of physical and chemical soil properties, two study areas were selected in contrasting mountain environments: Edroso, Vinhais municipality, NE Portugal, with typical Mediterranean climate, and Revelhe, Fafe, NW Portugal, with a strong ocean-influenced climate. In both, sampling was carried out in contiguous areas burnt and not burnt, covered by shrub vegetation, predominantly Cytisus multiflorus and Ulex europeus. In each study area (Edroso and Revelhe) 16 locations were selected for soil sampling (8 in the burned area and 8 in the not burnt area), six months after fire occurrence. Disturbed soil samples were collected in the layers 0-5, 5-10, 10-15, 15-20 and 20-30 cm depth, for assessing organic matter, N, P and K concentration, cation exchange capacity and related determinations, soil pH, electrical conductivity and soil texture. Undisturbed samples were collected, in 100 cm3 cylinders, to determine bulk density in the same above mentioned layers, and permeability in the 0-5 cm layer. Compared results of burnt and not burnt areas in Edroso and Revelhe study sites, show that coarse elements content and permeability decreased and bulk density slightly increased with the fire effect. Chemical properties in both sites changed with after fire, as organic matter content, exchangeable Al and cation exchange capacity increased, the opposite trend being found for phosphorus, sum of exchangeable bases and electrical conductivity. Potassium, total nitrogen and exchangeable acidity showed different soil responses to fire in the two study areas. Results stress the clear effects of fire on fertility related soil

  17. Linderiella jebalae sp. nov. (Crustacea: Branchiopoda: Anostraca), a new species from the Rif mountains (northern Morocco).

    PubMed

    Boix, Dani; Sala, Jordi; Escoriza, Daniel; Alonso, Miguel

    2016-01-01

    A new species of fairy shrimp, Linderiella jebalae sp. nov., was found in temporary ponds located in the Rif region of northern Morocco. Morphological characters of females, such as the basal long warty outgrowth of the antennae, the highly developed cuticular papillae in the second genital segment, and the presence of a keel-shaped process directed posteriorly in dorsal side of the brood pouch, clearly distinguish this species from the others of the genus. In the case of males, the basiomedial antennal outgrowth and the distal segment of the antenna are diagnostic features for the species. Cyst ornamentation, characterized by thick, blunt and sometimes truncated spines, also separate this species. This is the fourth known Palaearctic Linderiella species, all of them described recently (from 1980s onwards) and located in a restricted area, from south-eastern France to Iberian Peninsula and Morocco. PMID:27470776

  18. Hydrology of Area 61, Northern Great Plains and Rocky Mountain Coal Provinces, Colorado and New Mexico

    USGS Publications Warehouse

    Abbott, P.O.; Geldon, Arthur L.; Cain, Doug; Hall, Alan P.; Edelmann, Patrick

    1983-01-01

    Area 61 is located on the Colorado-New Mexico boundary in Huerfano and Las Animas Counties, Colorado, and Colfax County, New Mexico, and includes the Raton Mesa coal region. The 5 ,900-square-mile area is an asymmetrical structural trough bounded by the Rocky Mountains on the west and the Great Plains on the east. The area is drained by the Huerfano, Apishapa, Purgatoire, and Canadian Rivers (and their tributaries), all tributary to the Arkansas River. The principal coal-bearing formations are the Vermejo Formation of Late Cretaceous age and the Raton Formation of Late Cretaceous and Paleocene age. Much of the coal in the area is of coking quality, important to the metallurgical industry. Topographic relief in the area is greater than 8,700 feet, and this influences the climate which in turn affects the runoff pattern of area streams. Summer thunderstorms often result in flash floods. Virtually all geologic units in the region yield water. Depth to ground water ranges from land surface to 400 feet. Surface and ground water in the area contain mostly bicarbonate and sulfate ions; locally in the ground water, chloride ions predominate. Potential hydrologic problems associated with surface coal mining in the area are water-quality degradation, water-table decline, and increased erosion and sedimentation.

  19. Geology and petrology of the Wooley Creek batholith, Klamath Mountains, northern California

    NASA Astrophysics Data System (ADS)

    Barnes, C. G.

    The Wooley Creek batholith was intruded into metamorphic rocks of the western Paleozoic and Triassic belt (TrPz) of the Klamath Mountains 162 + or -2 my ago. The batholith crosscut a thrust fault between the lowest subunit of the TrPz, the Rattlesnake Creek terrane, and overlying Hayfork terrain metasediments. Contact metamorphic assemblages in the wall rocks show that the structurally deepest part of the pluton crystallized at about 7.5kb whereas the structurally shallowest part crystallized at about 3kb. The batholith and its host rocks were subsequently thrust over low-density rocks of the Galice Fm. and then tilted toward the southwest, presumably by regional doming. The Wooley Creek batholith is gradationally zoned from two-pyroxene gabbro in the deepest part to hornblende-biotite granite in the shallowest part. The plutonic rocks fall on two distinct chemical trends that correspond to rocks that contain pyroxene and rocks with only hornblende and biotite as mafic minerals. Pyroxene-bearing rocks are structurally lower and are enriched in Mg, Ca, Cr, Ni, Co, and Sc.

  20. Early Paleozoic blueschist from the schist of Skookum Gulch, eastern Klamath Mountains, northern California

    SciTech Connect

    Cotkin, S.J. ); Cotkin, M.L. ); Armstrong, R.L. )

    1992-05-01

    Late Ordovician blueschist from the schist of Skookum Gulch, eastern Klamath Mountains, California, is the oldest known blueschist in California and one of the oldest in North America. Lawsonite-bearing glaucophane schist occurs as lenses intimately interlayered with chlorite schist, quartz-albite schist, and dolomite marble. Detailed investigation of a portion of the Skookum Gulch schist demonstrates that these rock types share a common deformational and metamorphic history. The first deformation occurred during blueschist metamorphism and produced similar-style isoclinal folds and an axial-planar foliation. During subsequent deformations, parallel-style open to tight folds and local kink bands deformed foliation but produced no recognizable recrystallization. A phengite Rb-Sr date of 447 {plus minus} 9 Ma (Late Ordovician) is statistically indistinguishable from previously published K-Ar dates and is interpreted as the time of blueschist-facies metamorphism. Mineral separates from one rock yield a date of 353 {plus minus} 18 Ma, suggesting resetting during a Devonian to Early Mississippian thermal event. The schist of Skookum Gulch is a critical component of the Middle Ordovician to Early Silurian Callahan event, which included volcanism, plutonism, metamorphism, deformation, and sedimentation and occurred in response to collisional tectonics. Paleontological and provenance information indicate that the Callahan event occurred relatively close to the North American continental margin. In this regard, features produced by the Callahan event record the earliest period of Phanerozoic plate convergence recognized within the US Cordillera.

  1. Development of an expert system for assessing trumpeter swan breeding habitat in the Northern Rocky Mountains.

    USGS Publications Warehouse

    Sojda, Richard S.; Cornely, John E.; Howe, Adele E.

    2002-01-01

    A decision support system for the management of the Rocky Mountain Population of Trumpeter Swans (Cygnus buccinators) is being developed. As part of this, three expert systems are also in development: one for assessing the quality of Trumpeter Swan breeding habitat; one for making water level recommendations in montane, palustrine wetlands; and one for assessing the contribution a particular site can make towards meeting objectives from as flyway perspective. The focus of this paper is the development of the breeding habitat expert system, which currently consists of 157 rules. Out purpose is to provide decision support for issues that appear to be beyond the capability of a single persons to conceptualize and solve. We propose that by involving multiple experts in the development and use of the systems, management will be significantly improved. The knowledge base for the expert system has been developed using standard knowledge engineering techniques with a small team of ecological experts. Knowledge was then coded using production rules organized in decision trees using a commercial expert system development shell. The final system has been deployed on the world wide web.

  2. Lower tropospheric ozone and aerosol measurements at a coastal mountain site in Northern California

    NASA Astrophysics Data System (ADS)

    Post, A.; Conley, S. A.; Zhao, Y.; Cliff, S. S.; Faloona, I. C.; Wexler, A. S.; Lighthall, D.

    2012-12-01

    Increasing concern over the impacts of exogenous air pollution in California's Central Valley have prompted the establishment of a coastal, high altitude monitoring site at the Chews Ridge Observatory (1550 m) approximately 30 km east of Point Sur in Monterey County. Six months of ozone and aerosol measurements are presented in the context of long-range transport and its potential impact on surface air quality in the southern San Joaquin Valley. Moreover, approximately monthly ozone surveys are conducted by aircraft upwind, over the Pacific Ocean, and downwind, over the Central Valley, to characterize horizontal and vertical transport across the coastal mountains. The measurements exhibit no systematic diurnal variations of ozone or water vapor, an indication that the site primarily samples lower free tropospheric air which has not been significantly influenced by either local emissions or convective coupling to the surface. Aerosol size is measured with a scanning mobility particle sizer and composition is analyzed with an 8-stage rotating drum impactor whose substrates are characterized by X-ray fluorescence. Various elemental ratios and back trajectory calculations are used to infer the temporal patterns of influence that long range transport has on California air quality.

  3. Active tectonics of the Devils Mountain Fault and related structures, northern Puget Lowland and eastern Strait of Juan de Fuca region, Pacific Northwest

    USGS Publications Warehouse

    Johnson, Samuel Y.; Dadisman, Shawn V.; Mosher, David C.; Blakely, Richard J.; Childs, Jonathan R.

    2001-01-01

    Information from marine high-resolution and conventional seismic-reflection surveys, aeromagnetic mapping, coastal exposures of Pleistocene strata, and lithologic logs of water wells is used to assess the active tectonics of the northern Puget Lowland and eastern Strait of Juan de Fuca region of the Pacific Northwest. These data indicate that the Devils Mountain Fault and the newly recognized Strawberry Point and Utsalady Point faults are active structures and represent potential earthquake sources.

  4. Fractal Characteristics of Soil Retention Curve and Particle Size Distribution with Different Vegetation Types in Mountain Areas of Northern China.

    PubMed

    Niu, Xiang; Gao, Peng; Wang, Bing; Liu, Yu

    2015-12-01

    Based on fractal theory, the fractal characteristics of soil particle size distribution (PSD) and soil water retention curve (WRC) under the five vegetation types were studied in the mountainous land of Northern China. Results showed that: (1) the fractal parameters of soil PSD and soil WRC varied greatly under each different vegetation type, with Quercus acutissima Carr. and Robina pseudoacacia Linn. mixed plantation (QRM) > Pinus thunbergii Parl. and Pistacia chinensis Bunge mixed plantation (PPM) > Pinus thunbergii Parl. (PTP) > Juglans rigia Linn. (JRL) > abandoned grassland (ABG); (2) the soil fractal dimensions of woodlands (QRM, PPM, PTP and JRL) were significantly higher than that in ABG, and mixed forests (QRM and PPM) were higher than that in pure forests (PTP and JRL); (3) the fractal dimension of soil was positively correlated with the silt and clay content but negatively correlated with the sand content; and (4) the fractal dimension of soil PSD was positively correlated with the soil WRC. These indicated that the fractal parameters of soil PSD and soil WRC could act as quantitative indices to reflect the physical properties of the soil, and could be used to describe the influences of the Return Farmland to Forests Projects on soil structure. PMID:26633458

  5. Pattern and process in Northern Rocky Mountain headwaters: Ecological linkages in the headwaters of the Crown of the Continent

    SciTech Connect

    Hauer, F.R.; Stanford, J.A.; Lorang, M.S.

    2007-02-15

    The Crown of the Continent is one of the premiere ecosystems in North America containing Waterton-Glacier International Peace Park, the Bob Marshall-Great Bear-Scapegoat Wilderness Complex in Montana, various Provincial Parks in British Columbia and Alberta, several national and state forest lands in the USA, and Crown Lands in Canada. The region is also the headwater source for three of the continent's great rivers: Columbia, Missouri and Saskatchewan that flow to the Pacific, Atlantic and Arctic Oceans, respectively. While the region has many remarkably pristine headwater streams and receiving rivers, there are many pending threats to water quality and quantity. One of the most urgent threats comes from the coal and gas fields in the northern part of the Crown of the Continent, where coal deposits are proposed for mountain-top removal and open-pit mining operations. This will have significant effects on the waters of the region, its native plants and animals and quality of life of the people.

  6. Tree competition and species coexistence in a Quercus--Betula forest in the Dongling Mountains in northern China

    NASA Astrophysics Data System (ADS)

    Hou, Ji-hua; Mi, Xiang-cheng; Liu, Can-ran; Ma, Ke-ping

    2006-09-01

    The population size structure, growth dynamics and mode of competition among adult trees (≥ 4 cm DBH) of six abundant tree species in a 5 ha study plot of a temperate deciduous forest in the Dongling Mountains in northern China were investigated using diffusion and growth dynamics models. In the year of 2000, two dominant species, Quercus liaotungensis and Betula dahurica accounted for ca. 68.69% of the total basal area and 52.71% of the total density of adult plants. Q. liaotungensis, Populus davidiana and Acer mono exhibited inverse J-shaped DBH distributions whereas Betula dahurica, B. platyphylla and Salix caprea had unimodal DBH distributions. One-sided interspecific competition was detected between some species combinations at the scale of the 5 ha study plot, and the competitive effect was mainly size-dependent rather than from species-specific interactions with large individuals in the canopy layer out competing smaller individuals in the understory. Symmetric competition was found between Q. liaotungensis and A. mono only. However, considering the straight line relationship of G ( t, x) - √{D(t, x)}, which suggests that competitive asymmetry is very low or absent, combined with the relatively low mortality of trees with a DBH larger than 4 cm, we speculate that asymmetric interspecific competition was not important in structuring this tree community. Regeneration characteristics of each species are most likely important in regulating species coexistence and stand dynamics in this forest.

  7. Late Holocene geomorphic record of fire in ponderosa pine and mixed-conifer forests, Kendrick Mountain, northern Arizona, USA

    USGS Publications Warehouse

    Jenkins, S.E.; Hull, Sieg C.; Anderson, D.E.; Kaufman, D.S.; Pearthree, P.A.

    2011-01-01

    Long-term fire history reconstructions enhance our understanding of fire behaviour and associated geomorphic hazards in forested ecosystems. We used 14C ages on charcoal from fire-induced debris-flow deposits to date prehistoric fires on Kendrick Mountain, northern Arizona, USA. Fire-related debris-flow sedimentation dominates Holocene fan deposition in the study area. Radiocarbon ages indicate that stand-replacing fire has been an important phenomenon in late Holocene ponderosa pine (Pinus ponderosa) and ponderosa pine-mixed conifer forests on steep slopes. Fires have occurred on centennial scales during this period, although temporal hiatuses between recorded fires vary widely and appear to have decreased during the past 2000 years. Steep slopes and complex terrain may be responsible for localised crown fire behaviour through preheating by vertical fuel arrangement and accumulation of excessive fuels. Holocene wildfire-induced debris flow events occurred without a clear relationship to regional climatic shifts (decadal to millennial), suggesting that interannual moisture variability may determine fire year. Fire-debris flow sequences are recorded when (1) sufficient time has passed (centuries) to accumulate fuels; and (2) stored sediment is available to support debris flows. The frequency of reconstructed debris flows should be considered a minimum for severe events in the study area, as fuel production may outpace sediment storage. ?? IAWF 2011.

  8. Fractal Characteristics of Soil Retention Curve and Particle Size Distribution with Different Vegetation Types in Mountain Areas of Northern China

    PubMed Central

    Niu, Xiang; Gao, Peng; Wang, Bing; Liu, Yu

    2015-01-01

    Based on fractal theory, the fractal characteristics of soil particle size distribution (PSD) and soil water retention curve (WRC) under the five vegetation types were studied in the mountainous land of Northern China. Results showed that: (1) the fractal parameters of soil PSD and soil WRC varied greatly under each different vegetation type, with Quercus acutissima Carr. and Robina pseudoacacia Linn. mixed plantation (QRM) > Pinus thunbergii Parl. and Pistacia chinensis Bunge mixed plantation (PPM) > Pinus thunbergii Parl. (PTP) > Juglans rigia Linn. (JRL) > abandoned grassland (ABG); (2) the soil fractal dimensions of woodlands (QRM, PPM, PTP and JRL) were significantly higher than that in ABG, and mixed forests (QRM and PPM) were higher than that in pure forests (PTP and JRL); (3) the fractal dimension of soil was positively correlated with the silt and clay content but negatively correlated with the sand content; and (4) the fractal dimension of soil PSD was positively correlated with the soil WRC. These indicated that the fractal parameters of soil PSD and soil WRC could act as quantitative indices to reflect the physical properties of the soil, and could be used to describe the influences of the Return Farmland to Forests Projects on soil structure. PMID:26633458

  9. Sedimentary and microbial record of the Middle/Late Ordovician phosphogenetic episode in the northern Holy Cross Mountains, Poland

    NASA Astrophysics Data System (ADS)

    Trela, Wiesław

    2008-01-01

    Numerous phosphorite beds and phosphatic nodules occur in the upper Middle and lower Upper Ordovician carbonate-shale succession of the Bukowiany Formation outcropping in the northern Holy Cross Mountains, central Poland. The vertical stacking pattern of this succession indicates that phosphatic and accompanying strata reflect a conformable sedimentary succession accumulated during a rise of relative sea level. The base of the Bukowiany Formation is marked by a conspicuous phosphorite horizon revealing a low net sediment accumulation rate reflecting a switch into a mesotrophic ecological system. This horizon was produced by reworking and redeposition of pristine phosphate sediment (e.g. by currents activity) during the late Darriwilian transgression. The overlying sedimentary record appears to reflect nucleation of the phosphate phase in the sediment-water interface and its subsequent burial by the accompanying sediment. The phosphatized tiny stromatolites and nodules preserved within the Bukowiany Formation indicate that benthic microbial communities played an important role in redistribution and concentration of phosphate during deposition of this succession.

  10. Evaluating the effects of mountain resort development on snowmelt and runoff production: a case study from northern New England, USA

    NASA Astrophysics Data System (ADS)

    del Peral, A.; Wemple, B.

    2012-04-01

    Over the last decade, significant developments at mountain resorts in northern New England, USA have occurred to maintain competitiveness with western (USA) ski resorts. This development has included expansion of trail networks and snowmaking and development of resort base infrastructure, including housing, retail and amenities. Permitting these developments has posed particular challenges for predicting the effects of development on runoff and water quality. In this study, we describe efforts to model the effects of ski area development on snowmelt and runoff using a distributed rainfall-runoff model. Our test cases include a forested control watershed and an adjacent watershed encompassing a premier New England alpine ski resort. Empirical results from these watersheds show substantial differences in spring snowmelt and annual water yield between the watersheds. We are evaluating the performance of the Distributed Soil Hydrology Vegetation Model (DHSVM) to model snowmelt and runoff from these watersheds in order to assess its utility for predicting changes in runoff associated with resort development. We use distributed snow pack measurements to validate model simulations of snow accumulation and melt. Our results replicate observed patterns of runoff production in the watershed and can be used to test the effects of alternate development schemes on spring stream flow and annual water yield.

  11. Diagenetic aspects of tertiary carbonates west of the Northern Oman Mountains, United Arab Emirates

    NASA Astrophysics Data System (ADS)

    El-Saiy, A. K.; Jordan, B. R.

    2007-08-01

    To the south of Al-Ain, United Arab Emirates (UAE), lies the large mountain of Jebel Hafit. It which consists of foredeep basin sediments, which face the obducted allochthonous formations of neo-Tethys oceanic crust and associated deep marine sediments (i.e., Semail Ophiolites and Hawasina sediments). The foredeep sediments formed during the Early Eocene-Miocene. They are considered to be the main Paleogene marine exposure in Eastern Arabia. They are made up of limestones and marls and constitute four main rock units, namely: Rus, Dammam, Asmari and Fars formations, respectively, from base to top. The Rus (Late Early Eocene) is made up of fossiliferous, dolomitized limestone. The Dammam Formation (Middle to Late Eocene) conformably overlies the Rus Formation and comprises shale, marl, and limestone. The Asmari Formation (Early to Middle Oligocene) conformably overlies the Dammam Formation and is made up of nodular limestone. This is the first in depth study of diagenesis within the Dammam Formation. The petrographic investigation of this work reveals that the original textural and compositional characteristics of the Dammam Formation were modified by cementation, micritization, neomorphism, dolomitization, and, to a lesser extent, dissolution, compaction, dedolomitization, and silicification. Cementation with calcite and, less commonly, dolomite and iron oxides, in addition to dissolution effects, are more evident in the upper part of the Dammam Formation. Silicification and dolomitization are also extensive in the upper part of the Dammam Formation. Shallow burial of the Dammam Formation sediments in a partially closed system resulted in their compaction and consequent cementation with calcite. These carbonates display a wide spectra of diagenetic features, reflecting different environments. Micritization and early phases of cementation with calcite (isopachous calcite) likely occurred in a marine phreatic environment. Dolomitization and silicification most likely

  12. Petrogenesis of the Barcroft pluton, northern White-Inyo Mountains, east-central California

    NASA Astrophysics Data System (ADS)

    Ernst, W. G.

    2013-03-01

    The White-Inyo Range lies within the regional transition from Paleozoic-Precambrian North American continental basement to outboard Mesozoic and younger accreted terranes and a superimposed Andean-type arc. In the central White Mountains, the metaluminous Barcroft granodiorite invaded a major NE-striking, SE-dipping high-angle reverse fault—the Barcroft break. Because it is a relatively isolated igneous body and is well exposed over an elevation range of 1,500-4,000 m, its thermal history and that of the surrounding superjacent section are clearer than those of nearly coeval, crowded plutons emplaced in the hotter Sierra Nevada belt. The Barcroft pluton was emplaced as a compositionally heterogeneous series of areally scattered melt pulses episodically injected over the approximate interval 167-161 Ma. The oldest dated rocks are relatively quartzofeldspathic, whereas the youngest is more ferromagnesian, suggesting progressive partial fusion of a relatively mafic protolith. Heavy rare earth-enriched zircons indicate that Barcroft melts were derived at mid-crustal depths from a previously emplaced metabasaltic protolith containing plagioclase but lacking garnet. Granodioritic magma genesis involved the possible mixing of mafic and felsic melts, as well as very minor assimilation of country rocks, but mainly by fractional fusion and crystallization. Bulk chemical, rare earth, and isotopic data suggest that analyzed Barcroft rocks are members of a single suite. Granodioritic rocks are slightly more magnetite-rich at higher elevations on the NE, nearer the roof of the pluton. Earlier thermobarometry chronicled cooling and re-equilibration of the Barcroft pluton from its margins inward, as well as from mid-crustal generation depths of ~25 km through ascent and stalling at ~10-12 km. Refractory phase assemblages crystallized along the pluton margins, whereas subsolidus minerals in the interior of the of body continued to exchange with upper crustal deuteric and

  13. Study on frozen nuclei in the winter season in the northern mountains of Madrid (Spain)

    NASA Astrophysics Data System (ADS)

    Marcos, J. L.; Sánchez, J. L.; Posada, R.; Gascón, E.; Fernández, S.; Hermida, L.; García-Ortega, E.; López, L.

    2012-04-01

    In the Framework of Studies that the Group for Atmospheric Physics from the University of León has been developing about winter precipitation in the mountains of Madrid, one of the experimental objectives consists of the measurement of concentration (L-1) of frozen nuclei (IN) at the ground level, using an isothermal cloud chamber. The Experimental Center is found in the reservoir in Sierra Guadarrama, located about 50 km north of Madrid, at a height of 1294 meters above sea level. The sample is of 234 days, of which 119 showed precipitation, corresponding to three winter seasons (2008/2009, 2009/2010 and 2010/2011). The chamber is capable of operating at different temperatures. Making use of past experiences, we set the working temperature at -23°C. The principle objectives of the study were, on one hand, to determine the distribution of nuclei concentrations, and on the other, to analyze if this distribution presented similar behaviour, extracting days with precipitation from the sample. The results show that the concentration of nuclei is low. To be exact, on 75% of the days analyzed, this statistic did not exceed 25 L-1. With respect to the second objective described, we saw that the distribution of the concentration stayed very similar in those days in which ground precipitation was registered. In other words, precipitation was not associated with an increase in the number of nuclei. Finally, given the relative proximity of the Experimental Center to the city of Madrid, we took measurements of aerosols to analyze their possible influence on the presence of the nuclei. The results did not allow us to infer a statistically significant relationship between both concentrations. Acknowledgements This study was supported by the following grants: CEN20091028; GRANIMETRO (CGL2010-15930); MICROMETEO (IPT-310000-2010-22 ) and LE220A11-2 (Junta de Castilla y León).

  14. The elevational pattern of microbial community and enzyme activity along the northern slop of Changbai Mountain

    NASA Astrophysics Data System (ADS)

    Xu, Zhiwei; Yu, Guirui; Zhang, Xinyu; Ge, Jianpin; He, Nianpeng; Wang, Qiufeng; Wang, Dan

    2014-05-01

    we present a comprehensive analysis of soil microbial community structure, enzyme activities and their role in soil organic matter mineralization along six elevations representing five typical vegetation types from forest to alpine tundra in Changbai Mountain, China. The results showed that the microbial PLFAs presented hump-shaped patterns along the elevation with the total microbial PLFAs highest in Ermans birch forest soil. The fungi to bacteria and gram positive to negative bacteria ratios increased along the elevation with the lowest values in Broad leaved forest and Dark-coniferous spruce-fir forest soil, respectively. The soil microbial community structures showed a biogeography distribution pattern in vertical direction with microbial community structures in Broad leaved forest and Mixed coniferous broad leaved forest different from other four sites. The soil enzyme activities in Broad leaved forest and Mixed coniferous broad leaved forest were significantly higher than in other four elevations. Principal component analysis (PCA) revealed substantial differences in soil microbial community composition among study sites, appeared to be driven primarily by MAT, MAP, soil temperature and content of silt & clay on the first principal component (PC1) which accounted for 87.1 % of the total sample variance. However, soil nutrients mainly responsible for the variation of soil enzyme activities. The soil organic matter mineralization rates tended to be highest in Ermans birch forest site and lowest in Dark-coniferous spruce-fir forest site and showed positive relationship with total microbial, bacterial and actinomycetes PLFAs. These findings could be used to facilitate interpretation of soil microbial community and ecological function in latitude forests ecosystem especially in volcanic forest ecosystem.

  15. Patterns of hybridization among cutthroat trout and rainbow trout in northern Rocky Mountain streams.

    PubMed

    McKelvey, Kevin S; Young, Michael K; Wilcox, Taylor M; Bingham, Daniel M; Pilgrim, Kristine L; Schwartz, Michael K

    2016-02-01

    Introgressive hybridization between native and introduced species is a growing conservation concern. For native cutthroat trout and introduced rainbow trout in western North America, this process is thought to lead to the formation of hybrid swarms and the loss of monophyletic evolutionary lineages. Previous studies of this phenomenon, however, indicated that hybrid swarms were rare except when native and introduced forms of cutthroat trout co-occurred. We used a panel of 86 diagnostic, single nucleotide polymorphisms to evaluate the genetic composition of 3865 fish captured in 188 locations on 129 streams distributed across western Montana and northern Idaho. Although introgression was common and only 37% of the sites were occupied solely by parental westslope cutthroat trout, levels of hybridization were generally low. Of the 188 sites sampled, 73% contained ≤5% rainbow trout alleles and 58% had ≤1% rainbow trout alleles. Overall, 72% of specimens were nonadmixed westslope cutthroat trout, and an additional 3.5% were nonadmixed rainbow trout. Samples from seven sites met our criteria for hybrid swarms, that is, an absence of nonadmixed individuals and a random distribution of alleles within the sample; most (6/7) were associated with introgression by Yellowstone cutthroat trout. In streams with multiple sites, upstream locations exhibited less introgression than downstream locations. We conclude that although the widespread introduction of nonnative trout within the historical range of westslope cutthroat trout has increased the incidence of introgression, sites containing nonadmixed populations of this taxon are common and broadly distributed. PMID:26865958

  16. Early Paleozoic magmatic events in the eastern Klamath Mountains, northern California

    SciTech Connect

    Wallin, E.T.; Mattinson, J.M.; Potter, A.W.

    1988-02-01

    New U-Pb zircon ages for nine samples of tonalite and pegmatitic trondhjemite from the Trinity ophiolite and associated melange reveal a complex history of magmatic activity extending back into the earliest Cambrian, much older than previously believed. Earlier investigations, based on limited data, recognized lower Paleozoic crustal elements in the eastern Klamath terrane (EKT) ranging in age from Middle Ordovician to Early to Middle Devonian. The new work in the Yreka-Callahan area of the EKT confirms the Ordovician (440-475 Ma) and younger ages, but reveals for the first time the presence of tonalitic rocks that crystallized during a narrow time interval at about 565-570 Ma. The authors also recognize younger, Late Silurian magmatism at 412 Ma. In the context of available mapping, these ages indicate that the Trinity ophiolite is broadly polygenetic because parts of it yield crystallization ages that span approximately 150 m.y. Superjacent dismembered units of probable early Paleozoic age may be tectonostratigraphically equivalent to the Sierra City melange in the northern Sierra Nevada.

  17. Early Paleozoic magmatic events in the eastern Klamath Mountains, northern California

    NASA Astrophysics Data System (ADS)

    Wallin, E. Timothy; Mattinson, James M.; Potter, A. W.

    1988-02-01

    New U-Pb zircon ages for nine samples of tonalite and pegmatitic trondhjemite from the Trinity ophiolite and associated melange reveal a complex history of magmatic activity extending back into the earliest Cambrian, much older than previously believed. Earlier investigations, based on limited data, recognized lower Paleozoic crustal elements in the eastern Klamath terrane (EKT) ranging in age from Middle Ordovician to Early to Middle Devonian. The new work in the Yreka-Callahan area of the EKT confirms the Ordovician (440-475 Ma) and younger ages, but reveals for the first time the presence of tonalitic rocks that crystallized during a narrow time interval at about 565-570 Ma. We also recognize younger, Late Silurian magmatism at 412 Ma. In the context of available mapping, these ages indicate that the Trinity ophiolite is broadly polygenetic because parts of it yield crystallization ages that span approximately 150 m.y. Superjacent dismembered units of probable early Paleozoic age may be tectonostratigraphically equivalent to the Sierra City melange in the northern Sierra Nevada.

  18. Quality improvement initiatives by Aga Khan Health Service in the mountains of northern Pakistan.

    PubMed

    Jassani, Kashif; Essani, Rozina Roshan Ali; Abbas, Nadeem; Ahmed, Rashida

    2015-01-01

    Improving health care quality in a resource constraint environment in an emerging economy that is in a hard-to-reach geographic terrain can become a challenge especially when it has to follow the international standard which AKHS, P envisions to implement across the nation in all of its health facilities. Healthcare of the nation is a responsibility which is shouldered by both the government and the private sector. Private-sector, however, remains under pressure as its resource size is limited and it remains subject to stringent regulation and quality control requirements regardless of whether it is in the remotest corner of the country where proper land routes are either lacking or not safe. This article shares the unique experience of AKHS, P in achieving ISO 9001:2008 International Quality Management System Certification. Particularly at one of the "world's highest valleys -situated at Gilgit Baltistan at an altitude of 13,083 ft. above sea level in Northern Pakistan. The experience was unique in terms of demonstrating and recording how a quality management system can be implemented in one of the most difficult to reach areas where compliance to international quality standards was previously unthinkable. PMID:26058290

  19. Environmental evolution in Picos de Europa (Cantabrian Mountains, Northern Spain) since the last glacial cycle.

    NASA Astrophysics Data System (ADS)

    Nieuwendam, Alexandre; Ruiz-Fernández, Jesús; Oliva, Marc; Lopes, Vera; Cruces, Anabela; da Conceição Freitas, Maria

    2015-04-01

    The Western Massif of the Picos de Europa includes some of the highest elevations of the Cantabrian Mountains. The maximum ice expansion in this limestone range during the last glacial cycle preceded the global Last Glacial Maximum. A 5.4 m long sedimentary sequence was collected from Belbín, a depression damned by a moraine in a mid-altitude environment of this massif. Using a combination of several approaches we have reconstructed the environmental stages and intensity of cryogenic processes since that period until today: (1) geomorphological mapping combining field evidences, aerial photographs and topographic maps; (2) lithostratigraphic description of the cores identifying different sedimentary units; (3) Grain-size analyses of the fine fraction by laser diffraction; and (4) quartz grains using Cailleux (1942) analysis with modifications from Mycielska-Dowgiałło and Woronko (1998). The studied accumulative kame terrace has preserved a Late Quaternary record with geomorphological and climatic events, variable accumulation rates, and distinct grain properties resulting from frost and chemical weathering. The basal dating of the sediments of this section shows that the maximum glacial extent occurred prior to 37.2 ka cal BP. The lithostratigraphic analysis of the section shows evidence of four major stages regarding the environmental evolution in the area: (1) from 37.2 to 29 ka there was a phase with intense periglacial activity and deposition of slope deposits; (2) from 29 to 22 ka, the depression of Belbín gradually infilled; (3) from 22 to 8 ka, a paleolake was present in the study site; (4) since 8 ka, the lake became infilled. Besides, human-induced fires started at 4.9 ka probably for grazing purposes. Based on the sediment stratigraphy the data presented, demonstrates that in Belbín area there have been persistent cryogenic conditions since the last glacial cycle until present-day, with different degrees of intensity and type of weathering processes

  20. Stable isotopic signatures of diachronous Andean mountain building from volcanic glass, Condoroma Basin, northern Altiplano, Peru

    NASA Astrophysics Data System (ADS)

    Saylor, J.; Horton, B. K.; Stockli, D. F.

    2012-12-01

    Recent stable isotopic analyses of pedogenic carbonates from the central Altiplano (~18S) suggest that the plateau may have uplifted rapidly between 10 and 6 Ma possibly in response to removal of mantle lithosphere. Climate modeling, however, suggests that gradual uplift may have produced a similar magnitude effect in the stable isotopic system of the central Altiplano in response to attainment of a critical elevation. We present the results of new stable isotope (δD) analyses of volcanic glass from the Condoroma Basin in southern Peru (~15S). Nonmarine sedimentation in this hinterland basin extended from ~20 to ~5 Ma. The basin fill is composed primarily of lacustrine and lake-margin lithofacies but, critically, contains records of multiple volcanic eruptions. Samples of volcanic glass, which hydrates in the presence of surface water within ~10 kyr following eruption, were separated from multiple volcanic levels in two stratigraphic sections. Analysis of the deuterium isotopic composition of the volcanic glass reveals an abrupt and pronounced decrease of approximately 50-70‰ in both stratigraphic sections. Analyses of multiple grain size fractions yield consistent δD values, providing additional confidence in the robustness of the data. (U-Th)/He analysis of zircons separated from volcanic strata indicate that this shift occurred at ~18-14 Ma; earlier than in the central Altiplano. Applying the modern lapse rate implies an elevation increase of ~2.5 km. However, the isotopic shift could be the result of attainment of a threshold elevation, rather than representing a rapid, large-magnitude uplift event. Nevertheless, temporal variations suggest that uplift was not a single, plateau-wide event but rather, that the northern Altiplano was rapidly uplifted or attained the critical elevation prior to the central Altiplano. The possible effects of a diachronous rise in the Andes have not fully been incorporated into climate models. These data point to a diachronous

  1. Hydrological consequences of landscape fragmentation in mountainous northern Vietnam: Buffering of Hortonian overland flow

    NASA Astrophysics Data System (ADS)

    Ziegler, Alan D.; Giambelluca, Thomas W.; Plondke, Don; Leisz, Stephen; Tran, Liem T.; Fox, Jefferson; Nullet, Michael A.; Vogler, John B.; Dao, Minh Troung; Vien, Tran Duc

    2007-04-01

    SummaryWe use a hydrology-based fragmentation index to explore the influence of land-cover distribution on the generation and buffering of Hortonian overland flow (HOF) in two disturbed upland basins in northern Vietnam (Tan Minh). Both the current degree of fragmentation in Tan Minh and the current spatial arrangement of buffers (relative to HOF source areas) provide only limited opportunities for infiltrating surface runoff from upslope source areas, in part because of the high connectivity of swidden fields on long hillslopes. The intentional placement of buffers below HOF sources and the reduction of the down-slope lengths of swidden fields could reduce the occurrence of HOF on individual hillslopes. Reduction of the total watershed total depth of HOF would require maintaining a sufficient area of buffering land covers; and this may necessitate the use of longer fallow periods. These measures are, however, counter to the land-practice trends witnessed in the last several decades (i.e., no buffers, cultivation of long slopes, and increasingly shorter fallow periods). The two most likely scenarios of future land-cover change in Tan Minh—one representing increased fragmentation, the other decreased—both lead to an increase in HOF because of reduced buffering potential. The unlikely scenario of abandonment of agriculture and subsequent regeneration of forest, leads to both less fragmentation and less HOF. The study highlights the hydrological impacts associated with fragmentation at Tan Minh, which is the product of decades of local and regional forcing factors that have dictated the degree and timing of timber removal and swiddening at the site.

  2. Paleogeographic implications of Tertiary sedimentary rocks within the northern Rawhide and Artillery Mountains, Arizona

    SciTech Connect

    Yarnold, J.C.; Dickinson, W.R. . Dept. of Geosciences)

    1993-04-01

    Geologic mapping and analysis of Oligocene-Miocene sedimentary rocks in the upper plate of the Buckskin-Rawhide detachment fault system (west-central Arizona) reveals a complex paleogeographic history during fault displacement. Within the study area, four upper-plate fault blocks are capped by homoclinal sedimentary sections that display fanning dip relationships indicating concurrent tilting and sedimentation. Four sedimentary assemblages recognized within the study area can be correlated between fault blocks. The basal assemblage consists of lacustrine rocks and interfingering fluvial strata composed of detritus derived from the granitic terrane surrounding the northern part of the study area; these sediments were deposited during the earliest stages of tilting of upper-plate fault blocks. The overlying lower assemblage consists of fine-grained lacustrine deposits, sandy conglomerate and breccia. During lower-assemblage deposition, mass-flow-dominated alluvial fans were shed from source areas consisting mainly of Mesozoic and Paleozoic rocks exposed to the south of the study area. Tilting of fault blocks continued during deposition of the lower assemblage and strongly affected dispersal patterns and lithofacies distributions. The middle assemblage consists of conglomerate and sandstone deposited by an extensive south-directed stream system that probably flowed off undistended parts of the hanging wall, across extended parts, and locally onto the footwall. The upper assemblage consists of sandy conglomerate deposited by a northeast-directed system of broad, shallow steams; these deposits display a variety of clast types, including Tertiary mylonitic, sedimentary, and volcanic rocks that were eroded from the upwarped footwall of the core complex and overlying klippen.

  3. Bagley Fire Sediment Study: Shasta-Trinity National Forest, Eastern Klamath Mountains, Northern California

    NASA Astrophysics Data System (ADS)

    Bachmann, S.; De La Fuente, J. A.; Hill, B.; Mai, C.; Mikulovsky, R. P.; Mondry, Z.; Rust, B.; Young, D.

    2013-12-01

    The US Forest Service is conducting a study of sediment mobilization, transport, and deposition on the Bagley Fire, which burned about 18,000 hectares in late summer, 2012, on the Shasta-Trinity National Forest, south of McCloud, CA. The fire area is in steep terrain of the Eastern Klamath Mountains that are underlain primarily by metasedimentary rock. The watersheds affected drain into the headwaters of Squaw Creek, along with small streams tributary to the McCloud and Pit Rivers, all of which flow into Shasta Lake Reservoir. In November and December of 2012, intense storms occurred over the fire area with estimated return intervals of 25-50 years, based on 4-day storm totals in ranging from 38 to 56 cm. The Squaw Creek storm response was unique for this area, in that it remained turbid for about 2 months following the storms. Subsequent small storms through June, 2013 have also generated prolonged turbidity. This may be attributable to the remobilization of fine particles temporarily stored in the channel network. Preliminary observations from field reconnaissance include the following: a) Erosional processes were dominated by sheet, rill, and gully erosion, and the resulting sediment delivered to channels was rich in fine particles and gravels; b) Landslides were infrequent, and as a result, a limited amount of large rock and logs were delivered to channels; c) Sediment laden flows occurred in most burned low order channels, but classic debris flows, those scouring all vegetation from channel bottoms, were very uncommon; d) Most road stream crossing culverts failed in high severity burn areas; e) Low gradient stream reaches in Squaw Creek were aggraded with fine sediment; f) Sustained high levels of turbidity occurred in the main stem of Squaw Creek. The goals of this study are to characterize relative roles of surface erosion, landslides, and debris flows in delivering sediment to streams after the fire, and if possible, to develop a rough sediment budget

  4. Large-Scale Landslides in Rapidly Uplifted and Extremely Snowy Mountains in the Northern Japanese Alps

    NASA Astrophysics Data System (ADS)

    Kariya, Y.; Sato, G.; Arai, M.

    2006-12-01

    Mount Shirouma-dake (2932 m ASL, 36.75°N, 137.75°E) and its surrounding mountains have experienced rapid uplift and snowy climate over the late Quaternary period. The geology of this area, which comprises Paleozoic to Mesozoic ultramafic/sedimentary/metamorphic rocks and Neogene to Quaternary volcanic rocks, is very complicated. In addition, glaciers existed during MIS4 and 2 (no glaciers currently exist). Moreover, the active faults in the piedmont area are significant. This is because according to trenching studies, they have produced large earthquakes with a 1100-2400 y interval in the Holocene epoch. Therefore, it is recognized that the environment of this area is conducive to the occurrence of a landslide. Although the landforms in this area have been well described from glacial/periglacial geomorphological viewpoints, few details are available on landslides. The local sustainable tourism with geohazard mitigation requires more information on landslides because this area provides a spectacular landscape and attracts many visitors. Since the 1970s, many lodging and tourism facilities have been developed for such visitors. This area has also hosted the 1998 Winter Olympics because of its snowy climate. We performed geomorphological/geological analysis of the landslides and found that landslides and their precursors (uphill-facing scarps etc.) are common in most altitudinal zones. Many different types of landslides are observed in the bedrock slopes. Slumping is a typical mode. Mass rock creep (sagging), shallow failure, toppling, and landslide complexes are also observed. However, debris avalanche is restricted to the area in which volcanic rocks are distributed. Sometimes, the collapse of unconsolidated debris such as tills, colluvium, and alluvium occurs. In most cases, it is difficult to determine the depths of deformed zones without drilling results; however, it is assumed that a few landslides have a slip surface with a depth of 100 m. In some cases, the

  5. Emerald mineralization and metasomatism of amphibolite, khaltaro granitic pegmatite - Hydrothermal vein system, Haramosh Mountains, Northern Pakistan

    USGS Publications Warehouse

    Laurs, B.M.; Dilles, J.H.; Snee, L.W.

    1996-01-01

    Emerald mineralization is found within 0.1- to 1-m-thick hydrothermal veins and granitic pegmatites cutting amphibolite within the Nanga Parbat - Haramosh massif, in northern Pakistan. The amphibolite forms a sill-like body within garnet-mica schist, and both are part of a regional layered gneiss unit of Proterozoic (?) age. The 40Ar/39Ar data for muscovite from a pegmatite yield a plateau age of 9.13 ?? 0.04 Ma. Muscovite from mica schist and hornblende from amphibolite yield disturbed spectra with interpreted ages of 9 to 10 Ma and more than 225 Ma, respectively, which indicate that peak Tertiary metamorphism reached 325 to 550??C prior to 10 Ma. Pegmatites were emplaced after peak metamorphism during this interval and are older than pegmatites farther south in the massif. At Khaltaro, simply zoned albite-rich miarolitic pegmatites and hydrothermal veins containing various proportions of quartz, albite, tourmaline, muscovite, and beryl are associated with a 1- to 3-m-thick heterogeneous leucogranite sill, that is locally albitized. The pegmatites likely crystallized at 650 to 600??C at pressures of less than 2 kbar. Crystals of emerald form within thin (0.20, 0.54-0.89 wt%), to pale blue beryl (<0.07, 0.10-0.63%), to colorless beryl (<0.07, 0.07-0.28%). The amphibolite is metasomatized in less than 20-cm-wide selvages that are symmetrically zoned around veins or pegmatites. A sporadic inner zone containing F-rich biotite, tourmaline, and fluorite, with local albite, muscovite, quartz, and rare beryl, gives way to an intermediate zone containing biotite and fluorite with local plagioclase and quartz, and to an outer zone of amphibolite containing sparse biotite and local quartz. The inner and intermediate zones experienced gains of K, H, F, B, Li, Rb, Cs, Be, Ta, Nb, As, Y and Sr, and losses of Si, Mg, Ca, Fe, Cr, V and Sc. The outer alteration zone has gained F, Li, Rb, Cs, and As. Oxygen isotope analyses of igneous and hydrothermal minerals indicate that a

  6. Variations in Soil Microbial Communities and Residues Along an Altitude Gradient on the Northern Slope of Changbai Mountain, China

    PubMed Central

    Zhang, Bin; Liang, Chao; He, Hongbo; Zhang, Xudong

    2013-01-01

    Altitudinally-defined climate conditions provide specific vegetation types and soil environments that could influence soil microbial communities, which in turn may affect microbial residues. However, the knowledge is limited in terms of the degree to which microbial communities and residues present and differ along altitude. In this study, we examined the soil microbial communities and residues along the northern slope of Changbai Mountain, China using phospholipid fatty acid (PLFA) and amino sugar analysis, respectively. Soil samples were taken from five different vegetation belts defined by climates. Principal component analysis (PCA) revealed substantial differences in soil microbial community composition among study sites, appeared to be driven primarily by soil pH and C/N ratio on the first principal component (PC1) which accounted for 50.7% of the total sample variance. The alpine tundra was separated from forest sites on the second principal component (PC2) by a signifiscantly higher amount of fungal PLFA (18:2ω6,9). Soil pH and C/N ratio were also correlated with the ratios of Gram-positive to Gram-negative bacteria (Gm+/Gm−), glucosamine to galactosamine (GluN/GalN), and glucosamine to muramic acid (GluN/MurA). Both total PLFAs and amino sugars were positively correlated with soil organic carbon, inorganic nitrogen, available phosphorus and potassium. We concluded that soil pH and C/N ratio were the most important drivers for microbial community structure and amino sugar pattern, while substrate availability was of great importance in determining the concentrations of microbial communities and residues. These findings could be used to facilitate interpretation of soil microbial community and amino sugar data derived from measurements in latitude or managed forests. PMID:23776630

  7. Wolf population dynamics in the U.S. Northern Rocky Mountains are affected by recruitment and human-caused mortality

    USGS Publications Warehouse

    Gude, J.A.; Mitchell, M.S.; Russell, R.E.; Sime, C.A.; Bangs, E.E.; Mech, L.D.; Ream, R.R.

    2012-01-01

    Reliable analyses can help wildlife managers make good decisions, which are particularly critical for controversial decisions such as wolf (Canis lupus) harvest. Creel and Rotella (2010) recently predicted substantial population declines in Montana wolf populations due to harvest, in contrast to predictions made by Montana Fish, Wildlife and Parks (MFWP). We replicated their analyses considering only those years in which field monitoring was consistent, and we considered the effect of annual variation in recruitment on wolf population growth. Rather than assuming constant rates, we used model selection methods to evaluate and incorporate models of factors driving recruitment and human-caused mortality rates in wolf populations in the Northern Rocky Mountains. Using data from 27 area-years of intensive wolf monitoring, we show that variation in both recruitment and human-caused mortality affect annual wolf population growth rates and that human-caused mortality rates have increased with the sizes of wolf populations. We document that recruitment rates have decreased over time, and we speculate that rates have decreased with increasing population sizes and/or that the ability of current field resources to document recruitment rates has recently become less successful as the number of wolves in the region has increased. Estimates of positive wolf population growth in Montana from our top models are consistent with field observations and estimates previously made by MFWP for 2008-2010, whereas the predictions for declining wolf populations of Creel and Rotella (2010) are not. Familiarity with limitations of raw data, obtained first-hand or through consultation with scientists who collected the data, helps generate more reliable inferences and conclusions in analyses of publicly available datasets. Additionally, development of efficient monitoring methods for wolves is a pressing need, so that analyses such as ours will be possible in future years when fewer resources

  8. Evaluation of trace elements contamination in cloud/fog water at an elevated mountain site in Northern China.

    PubMed

    Liu, Xiao-huan; Wai, Ka-ming; Wang, Yan; Zhou, Jie; Li, Peng-hui; Guo, Jia; Xu, Peng-ju; Wang, Wen-xing

    2012-07-01

    Totally 117 cloud/fog water samples were collected at the summit of Mt. Tai (1534m a.s.l.)-the highest mountain in the Northern China Plain. The results were investigated by a combination of techniques including back trajectory model, regional air quality and dust storm models, satellite observations and Principal Component Analysis. Elemental concentrations were determined by Inductively Coupled Plasma Mass Spectrometry, with stringent quality control measures. Higher elemental concentrations were found at Mt. Tai compared with those reported by other overseas studies. The larger proportions and higher concentrations of toxic elements such as Pb and As in cloud/fog water compared with those in rainwater at Mt. Tai suggests higher potential hazards of cloud/fog water as a source of contamination in polluted areas to the ecosystem. Peak concentrations of trace elements were frequently observed during the onset of cloud/fog events when liquid water contents of cloud/fog water were usually low and large amount of pollutants were accumulated in the ambient air. Inverse relationship between elemental concentrations and liquid water contents were only found in the samples with high electrical conductivities and liquid water contents lower than 0.3gm(-3). Affected mainly by the emissions of steel industries and mining activities, air masses transported from south/southwest of Mt. Tai were frequently associated with higher elemental concentrations. The element Mn is attributed to play an important role in the acidity of cloud/fog water. The composition of cloud/fog water influenced by an Asian dust storm event was reported, which was seldom found in the literature. PMID:22503636

  9. Eye-to-eye with a mega-sheath fold: A case study from Wadi Mayh, northern Oman Mountains

    NASA Astrophysics Data System (ADS)

    Searle, M. P.; Alsop, G. I.

    2007-11-01

    Sheath folds are highly curvilinear folds, typically considered to develop by hinge rotation toward the transport direction during intense deformation. Most sheath folds are recognized on the centimeter to meter scale, with very few detailed studies of larger kilometer-scale structures. We here present evidence for a mega-scale sheath fold superbly exposed in the northern Oman Mountains. The Saih Hatat culmination consists of an exhumed high-pressure subduction zone with deep-level eclogites and garnet blueschists (As Sifah unit), epidote blueschists (Hulw unit) and carpholite-bearing metasediments (part of the “Upper plate”). Sheath folds are present at a variety of scales throughout the As Sifah, Hulw, and Upper plate tectonic packages. Curvilinear fold hinges along a 15-km-long profile outline the Wadi Mayh mega-sheath fold, which closes to the SSW and faces to the NNE. It consists of at least four secondary sheath folds with cross-sectional (y-z) eye folds measuring 200 m stacked on top of one another within Permian and Triassic shelf carbonates. These eye folds display highly elliptical geometries (Ryz > 5) and cat's-eye fold patterns consistent with simple/general shear. The sheath fold is enveloped by Ordovician and older rocks that do not show equal amounts of internal deformation. The upper bounding envelope is a detachment that has been subsequently sheath folded. The lower boundary of the sheath fold is the Upper plate-Lower plate detachment, which forms a major high-strain shear zone showing little vertical displacement but significant horizontal displacement. The sheath fold displays a SSW elongation (x axis) of at least 15 km and possibly up to 25 km, coupled with significant amounts of vertical flattening and WNW-ESE shortening.

  10. Perspectives on Precambrian basement architecture in the northern US Rocky Mountains from inherited zircons in the Idaho batholith

    NASA Astrophysics Data System (ADS)

    Gaschnig, R. M.; Vervoort, J. D.; Lewis, R.; Tikoff, B.

    2010-12-01

    Inherited accessory minerals in Phanerozoic plutons can often provide key information about Precambrian crystalline basement that is poorly exposed. Here, we present U-Pb age and Hf isotope data for Precambrian inherited zircons in the Cretaceous-Paleocene Idaho batholith, in anticipation of the IDOR (Idaho-Oregon) Earthscope Project. In situ U-Pb dating of these inherited zircons reveals major differences in the crustal architecture between the southern Atlanta and northern Bitterroot lobes of the Idaho batholith. Inheritance in the Atlanta lobe is dominated by ages of ~2.55 Ga and ~670 Ma, with the older age more prevalent in the southernmost samples. We interpret these ages to record the presence of significant Neoarchean and Neoproterozoic igneous or metaigneous rock in the subsurface since both ages can be correlated with known local bedrock exposures and xenoliths (in the case of the Neoarchean). In contrast, inherited zircons from the Bitterroot lobe yield a continuous age distribution between 1.9 and 1.4 Ga, which is remarkably similar to the detrital zircon age spectra of much of the Mesoproterozoic Belt Supergroup. Belt Supergroup rocks are the likely source of the zircon inheritance, implying that the inheritance pattern we see in the Bitterroot samples provides little new information on the crystalline basement on which the Belt Supergroup was deposited. The extent of Archean inheritance in the Atlanta lobe suggests that the Archean crust exposed in the Albion and Grouse Creek Mountains and present beneath the central and eastern Snake River Plain extends as far west as the Pre-Mesozoic continental margin and further north than previously thought, making it a potentially important piercing point in reconstructions of the Rodinian supercontinent. In situ Hf isotopic analyses of the Archean cores provide evidence for previously existing Early Archean crustal components to this crustal block, similar to components of the Wyoming Province to the east.

  11. Hurricane Mountain Formation melange: history of Cambro-Ordovician accretion of the Boundary Mountains terrane within the northern Appalachian orthotectonic zone

    SciTech Connect

    Boone, G.M.; Boudette, E.L.

    1985-01-01

    The Hurricane Mountain Formation (HMF) melange and associated ophiolitic and volcanogenic formations of Cambrian and lowermost Ordovician age bound the SE margin of the Precambrian Y (Helikian) Chain Lakes Massif in western Maine. HMF melange matrix, though weakly metamorphosed, contains a wide variety of exotic greenschist to amphibolite facies blocks as components of its polymictic assemblage, but blocks of high-grade cratonal rocks such as those of Chain Lakes or Grenville affinity are lacking. Formations of melange exposed in structural culminations of Cambrian and Ordovician rocks NE of the HMF in Maine and in the Fournier Group in New Brunswick are lithologically similar and probably tectonically correlative with the HMF; taken together, they may delineate a common pre-Middle Ordovician tectonic boundary. The authors infer that the Hurricane Mountain and St. Daniel melange belts define the SE and NW margins of the Boundary Mountains accreted terrane (BMT), which may consist of cratonal basement of Chain Lakes affinity extending from eastern Gaspe (deBroucker and St. Julien, 1985) to north-central New Hampshire. The Laurentian continental margin, underlain by Grenville basement, underplated the NW margin of this terrane, marked by the SDF suture zone, in late Cambrian to early Ordovician time, while terranes marked by Cambrian to Tremadocian (.) lithologies dissimilar to the Boundary Mountains terrane were accreted to its outboard margin penecontemporaneously. The docking of the Boundary Mountains terrane and the initiation of its peripheral melanges are equated to the Penobscottian disturbance.

  12. {open_quotes}Black Gold{close_quotes} leads to new structural interpretation, Northern Sangre de Cristo Mountains/Northeast San Luis Basin

    SciTech Connect

    Watkins, T.A.; Belcher, J.S.; Gries, R.

    1995-06-01

    In the course of exploring for gold along the east margin of the Rio Grande Rift (northern Sangre de Cristo Mountains and northeastern San Luis Basin) live Cretaceous oil was discovered in fractured Precambrian gneiss in 25 of 42 shallow drill holes. Geologic mapping located two outcrops of Mesozoic sediments along the west flank of the Sangre de Cristo Mountains. Mancos Shale, Dakota Group and Morrison Formation sediments were identified from 17 drill holes. These are the first known occurrences of Mesozoic sediments in the area. Previous investigations had concluded that the Mesozoic section eroded from the San Luis uplift during the Laramide. Surface and subsurface geologic data was integrated with gravity, magnetic and seismic surveys for a new structural interpretation. The San Luis Basin is separated from the mountains by an intermediate block and the main basin-bounding fault is three miles west-southwest of the mountain front. A major low-angle, normal fault or detachment fault is related to Miocene rifting. A thick section of Mesozoic sediments are interpreted to be present in the hanging wall of this low angle fault. Buried and thermally matured in a Laramide intermountane basin, these sediments are likely the source of the present day oil found in Precambrian rocks.

  13. Geomorphic analysis of transient landscapes in the Sierra Madre de Chiapas and Maya Mountains (northern Central America): implications for the North American-Caribbean-Cocos plate boundary

    NASA Astrophysics Data System (ADS)

    Andreani, L.; Gloaguen, R.

    2016-01-01

    We use a geomorphic approach in order to unravel the recent evolution of the diffuse triple junction between the North American, Caribbean, and Cocos plates in northern Central America. We intend to characterize and understand the complex tectonic setting that produced an intricate pattern of landscapes using tectonic geomorphology, as well as available geological and geophysical data. We classify regions with specific relief characteristics and highlight uplifted relict landscapes in northern Central America. We also analyze the drainage network from the Sierra Madre de Chiapas and Maya Mountains in order to extract information about potential vertical displacements. Our results suggest that most of the landscapes of the Sierra Madre de Chiapas and Maya Mountains are in a transient stage. Topographic profiles and morphometric maps highlight elevated relict surfaces that are characterized by a low-amplitude relief. The river longitudinal profiles display upper reaches witnessing these relict landscapes. Lower reaches adjust to new base-level conditions and are characterized by multiple knickpoints. These results backed by published GPS and seismotectonic data allow us to refine and extend existing geodynamic models of the triple junction. Relict landscapes are delimited by faults and thus result from a tectonic control. The topography of the Sierra Madre de Chiapas evolved as the result of (1) the inland migration of deformation related to the coupling between the Chiapas Massif and the Cocos forearc sliver and (2) the compression along the northern tip of the Central American volcanic arc. Although most of the shortening between the Cocos forearc sliver and the North American Plate is accommodated within the Sierra de Chiapas and Sierra de los Cuchumatanes, a small part may be still transmitted to the Maya Mountains and the Belize margin through a "rigid" Petén Basin.

  14. Geomorphic analysis of transient landscapes from the Sierra Madre de Chiapas and Maya Mountains (northern Central America): implications for the North American-Caribbean-Cocos plate boundary

    NASA Astrophysics Data System (ADS)

    Andreani, L.; Gloaguen, R.

    2015-09-01

    We use a geomorphic approach in order to unravel the recent evolution of the diffuse triple junction between the North American, Caribbean, and Cocos plates in northern Central America. The complex tectonic setting produced an intricate pattern of landscapes that we try to systemize using remote sensing tectonic geomorphology and available geological and geophysical data. We classify regions with specific relief characteristics and highlight uplifted relict landscapes in northern Central America. We also analyze the drainage network from the Sierra Madre de Chiapas and Maya Mountains in order to extract information about potential vertical displacements. Our results suggest that most of the landscapes of the Sierra Madre de Chiapas and Maya Mountains are in transient stage. Topographic profiles and morphometric maps highlight elevated relict surfaces that are characterized by a low amplitude relief. The river longitudinal profiles display upper reaches witnessing these relict landscapes while lower segments characterized by multiple knickpoints, that adjust to new base-level conditions. These results backed by published GPS and seismotectonic data allow us to refine and extend existing geodynamic models of the triple junction. Relict landscapes are delimited by faults and thus result from a tectonic control. The topography of the Sierra Madre de Chiapas evolved as the result of (1) the inland migration of deformation related to the coupling between the Chiapas Massif and the Cocos fore-arc sliver, and (2) the compression along the northern tip of the Central America Volcanic Arc. Although most of the shortening between the Cocos fore-arc sliver and the North American plate is accommodated within the Sierra de Chiapas and Sierra de los Cuchumatanes, a small part may be still transmitted to the Maya Mountains and the Belize margin through a "rigid" Petén basin.

  15. Ground Penetrating Radar Profiles of Breached Anticlinal Ridges in the Northern Piedmont of the San Bernardino Mountains in Southern California

    NASA Astrophysics Data System (ADS)

    Bobyarchick, A. R.; Eppes, M. C.; Diemer, J. A.; Cathey, R. B.; Cottingham, M. A.; Eckardt, I. J.; Shiflet, J. E.; Waldron, A. J.

    2006-12-01

    The northern piedmont of the San Bernardino Mountains contains kinematic elements characteristic of the Mojave block dextral plate boundary zone between the North American and Pacific plates and the complex convergent Transverse Ranges partition of that motion here represented by the North Frontal thrust system. Predominantly lateral slip in the central Mojave block is carried by the Helendale fault through Lucerne Valley and southward to intersect the North Frontal thrust system in the San Bernardino Mountains. Active anticlinal flexures and partially emergent north-verging thrust faults have deformed Pleistocene alluvial fans and older rocks into east-trending ridges in the piedmont on both sides of the Helendale fault. The Cougar Buttes anticline underlies such a ridge east of the fault and is breached by contemporaneous orthogonal washes in several places along strike of the anticline. Greater relief occurs where the alluvial fans comprise carbonate- cemented soils and particularly resistant, prominent petrocalcic horizons. It is within these incised valleys that the sequence of Tertiary through Pleistocene deposits show that the asymmetric anticline is cored by a thrust fault. In order to examine more closely the fold-fault association in the Cougar Buttes anticline and suggest possible kinematic models, we conducted several ground penetrating radar (GPR) profiles at different levels across the ridge. Relatively superior relief in some washes allowed us to conduct profiles along the present topographic ridge crests (and thus along the crestal zone of the fold) and also along wash bottoms to provide profiles at the level of the fold's core. We used a GSSI SIR-3000 GPR system equipped with a monostatic 100 MHz antennae set to continuous recording mode; traverses over very irregular ground were done in point data mode. The system was set up with nominal high and low cutoff filters and automatic gain control, but we found that AGC overly amplified multiples or

  16. Simulating the effects of fire and climate change on northern Rocky Mountain landscapes using the ecological process model FIRE-BGC

    SciTech Connect

    Keane, R.E.; Ryan, K.; Running, S.W.

    1995-12-31

    A mechanistic successional model, FIRE-BGC (a FIRE BioGeoChemical succession model), has been developed to investigate the role of fire and climate on long-term landscape dynamics in northern Rocky Mountain coniferous forests. This FIRE-BGC application explicitly simulates fire behavior and effects on landscape characteristics. Predictions of evapotranspiration are contrasted with and without fire over 200 years of simulation for the McDonald Drainage, Glacier National Park under current climate conditions are provided as an example of the potential of FIRE-BGC.

  17. Use of digital Munsell color space to assist interretation of imaging spectrometer data: Geologic examples from the northern Grapevine Mountains, California and Nevada

    NASA Technical Reports Server (NTRS)

    Kruse, F. A.; Knepper, D. H., Jr.; Clark, R. N.

    1986-01-01

    Techniques using Munsell color transformations were developed for reducing 128 channels (or less) of Airborne Imaging Spectrometer (AIS) data to a single color-composite-image suitable for both visual interpretation and digital analysis. Using AIS data acquired in 1984 and 1985, limestone and dolomite roof pendants and sericite-illite and other clay minerals related to alteration were mapped in a quartz monzonite stock in the northern Grapevine Mountains of California and Nevada. Field studies and laboratory spectral measurements verify the mineralogical distributions mapped from the AIS data.

  18. Holocene Paleoenvironment of the North-central Great Basin: Preliminary Results from Favre Lake, Northern Ruby Mountains, Nevada

    NASA Astrophysics Data System (ADS)

    Starratt, S.; Wahl, D.; Wan, E.; Anderson, L.; Wanket, J.; Olson, H.; Lloyd-Davies, T.; Kusler, J.

    2009-12-01

    Little is known about Holocene climate variability in north-central Nevada. This study aims to assess changes in watershed vegetation, fire history, lake levels and limnological conditions in order to understand secular to millennial-scale changes in regional climate. Favre Lake (2,899 m a.s.l.; 12 m deep; 7.7 hectares) is a flow-through lake in the northern Ruby Mountains. The primary sources of influent, both of which appear to be intermittent, are Castle Lake (2,989 m a.s.l.) and Liberty Lake (3,077 m a.s.l.). The bedrock of the three lake basins is early Paleozoic marble and Mesozoic granite and metamorphic rocks. Bathymetric maps and temperature, pH, salinity, and conductivity profiles have been generated for Favre Lake. Surface samples and a series of cores were also collected using a modified Livingstone piston corer. The presence of the Mazama ash in the basal sediment (~4 m below the sediment/water interface) indicates the record extends to ~7,700 cal yr B.P. Magnetic susceptibility (MS) and loss-on-ignition data indicate that the sediments in the lowest part of the core contain primary and reworked Mazama ash. About 2,000 years ago CaCO3 increased from 2 to 3% of the inorganic sediment. The upper 25 cm of the core are marked by an increase in MS which may indicate increased erosion due to grazing. Between about 7,700 and 6,000 cal yr B.P. the diatom flora is dominated by a diverse assemblage of benthic species. The remainder of the core is dominated by Fragilaria, suggesting that lake level rose and flooded the shelf that surrounds the depocenter of the lake. This is supported by changes in the abundance of the aquatic fern Isoetes. Pinus and Artemisia dominate the pollen record, followed by subordinate levels of Poaceae, Asteraceae, Amaranthaceae, and Sarcobatus. The late early Holocene (7,700-6,000 cal yr B.P.) is dominated by Pinus which is present in reduced amounts during the middle Holocene (6,000-3,000 cal yr B.P.) and then returns to dominance in

  19. Timing of Accretion and Mountain-Building in The Northern Andes of Colombia through Low-Temperature Thermochonology

    NASA Astrophysics Data System (ADS)

    Vinasco, C. J.; Restrepo-Moreno, S. A.; Marín, M. I.; Botero, M.; Bermudez, M. A.; Min, K. K.; Foster, D. A.; Noriega, S., Sr.; Montoya, E., Sr.; Londoño, L., Sr.; Bernet, M.

    2015-12-01

    Orogenic configuration of the Northern Andes is closely associated to accretional processes since the Upper Cretaceous. In Colombia, the regional boundary between a Paleozoic continental domain to the east and Cretaceous accreted terrenes to the west is well exposed in several E-W sections near Medellin City and along the Cauca River, which occupies a major depression located between the Central and Western cordilleras. The area is dominated by the N-S trending Romeral Fault System (RFS) that can be traced to southern Ecuador. Relationships between the RFS and W-SW verging thrust system are unknown, although they represent key components of a transpressional orogeny. To understand timing of accretion and associated mountain building processes, we performed (U-Th)/He and fission track dating on samples derived from vertical profiles in cordilleran massifs. Samples were collected along four vertical profiles on two distinct litho-tectonic units: (1) three vertical profiles in the older eastern realm corresponding to metamorphic basement rocks of the Paleozoic Paleo-continental margin and associated Cretaceous intrusives, and (2) one vertical profile in the Mande batholith, Eocene in age at the eastern portion of the Panama Chocó Block (PCB) . The resulting zircon (U-Th)/He (ZHe) ages show a clear contrast between the ancient eastern realm (~50-60 Ma) and the Mande Batholith (~30-40 Ma). Apatite (U-Th)/He (AHe) ages also show a strong contrast with 23-42 Ma for the eastern realm and a well defined cluster at ~4 Ma for the Mande Batholith. These preliminary results suggest distinctive cooling histories for the two litho-tectonic blocks. The Mande batholith (western block) records both the late Eocene and Pliocene events whereas the ancient eastern block does not preserve any of these events. The Paleocene events recorded by the eastern block are probably related to the Laramic orogenetic phase. Finally, elevation-invariable ZHe ages from the ancient eastern block

  20. D- 18O enriched waters of the Coast Range Mountains, northern California: Connate and ore-forming fluids

    NASA Astrophysics Data System (ADS)

    Peters, E. Kirsten

    1993-03-01

    D and 18O enriched waters of several weight percent salinity issue from hot and cold springs in Franciscan Complex and Great Valley Sequence rocks in the northern Coast Range Mountains of California. Although these waters have been described separately in the past and called "metamorphic," "connate," and "serpentinizing fluids," this study shows that the hot and cold springs are all fed by one source of water—trapped Cretaceous seawater modified by a variety of reactions. The district is an example of the complexities of subsurface waters and their importance for our understanding of metamorphic fluid sources, oil-field waters, and ore transport problems. The subsurface waters have a range of δ 34S values, including some near marine sulfate values (+20%.), and δ 13C near marine calcite values (0%.). Strontium isotopic signatures in the spring waters are derived from the Great Valley Sequence ( 87Sr /86Sr values near 0.705). The most saline spring pool is lined with serpentine phases found together as a fine white precipitate and has a pH of 11. One portion of the subsurface water is heated and reduced; it transports Au, Ag, Sb, As, and Hg to the surface (gold grades of the hot spring precipitates range from less than 1 ppm to over 10 ppm). These heated waters are chemically and isotopically similar to the fluids which formed Au mineralization at the nearby McLaughlin gold mine. The hot springs precipitate pyrite and native sulfur and are supersaturated with respect to calcite. Other springs are less saline and are oxidized, cooler, and diluted versions of the hot spring fluid. They do not carry ore metals but they are supersaturated with respect to silica and calcite. 3He /4He ratios of the springs gases are all above atmospheric values and indicate a possible magmatic component, consistent with the presence of Quaternary Clear Lake Volcanics. 129I data yield a minimum age of 60-80 Ma for the source of the iodide in the waters, consistent with the connate

  1. Examining soil erosion and nutrient accumulation in forested and agriculture lands of the low mountainous area of Northern Vietnam

    NASA Astrophysics Data System (ADS)

    Pham, A. T.; Gomi, T.; Takahisa, F.; Phung, K. V.

    2011-12-01

    We examined soil erosion and nutrient accumulations in the Xuanmai area located in the low mountainous region of Northern Vietnam, based on field investigations and remote sensing approaches. The study area had been degraded by land-use change from forest to agriculture in the last 20 years. In contrast, around the study area, the Vietnam government promoted reforestation projects. Such changes in land-use conditions, which may or may not be associated with vegetation ground cover conditions, potentially alter soil erosion and nutrient accumulation. We selected 10 dominant land-use types including forested land (e.g., Pinus massoniana and Acacia mangium plantation) agriculture land (e.g., Cassava), and bare land. We established three 1 x 1 m plots in each land-use type in September 2010. Vegetation biomass, litter cover, soil erosion (height of soil pedestal), and soil physical (soil bulk density and particle size distribution) and chemical properties (Total soil carbon, nitrate, and phosphorus) were measured. Height of soil pedestal can be a record of soil erosion by rain splash during rainy periods from April to August (prior to our field study). We also conducted remote sensing analysis using Landsat TM images obtained in 1993, 2000, and 2007 for identifying temporal patterns of land-use types. We found that the intensity of soil erosion depended primary on current vegetation ground cover condition with no regard of land-use. Hence, nutrient accumulation varied among vegetation ground cover and soil erosion. Remote sensing analysis suggested that shrub and bare lands had been altered from forested land more recently. Our finding suggested that variability of soil nutrient conditions can be associated with long-term soil erosion and production processes. Findings of our study are that: (1) current vegetation and litter ground cover affected the amount of surface soil erosion, and (2) legacy of land-use can be more critical for soil nutrient accumulation. Both

  2. Coseismic and blind fault of the 2015 Pishan Mw 6.5 earthquake: Implications for the sedimentary-tectonic framework of the western Kunlun Mountains, northern Tibetan Plateau

    NASA Astrophysics Data System (ADS)

    Lu, Renqi; Xu, Xiwei; He, Dengfa; Liu, Bo; Tan, Xibin; Wang, Xiaoshan

    2016-04-01

    On 3 July 2015, the Mw 6.5 Pishan earthquake occurred in the western Kunlun Mountains front, at the northern margin of the Tibetan Plateau. To reveal the sedimentary-tectonic framework of the seismically active structure, three high-resolution seismic reflection profiles and well drilling data were collected for seismic interpretation. The western Kunlun Mountains and Tarim Basin have two gypseous detachments and one basement detachment that control the tectonic framework and structural deformation. The upper gypseous detachment (D1) is in the lower Paleocene, and the middle gypseous detachment (D2) is in the Middle to Lower Cambrian. A Neogene shallow thrust system is developing above D1 and includes the Zepu fault (F2) and Mazar Tagh fault (F3). A deep thrust system is developing between D1 and D2 and forms a large-scale structural wedge beneath the western Kunlun Mountains front. The Pishan Mw 6.5 earthquake was triggered on a frontal blind fault of this deep thrust system. The lower detachment is in the Proterozoic basement (D3), which extends into the Tarim Basin and develops another deep thrust (F4) beneath the F3 belt. D1, D2, D3, and the Tiekelike fault (F1) merge together at depth. Crustal shortening of the western Kunlun Mountains front continues for approximately 54 km. Two tectonic evolutionary stages have occurred since the Miocene according to sedimentary unconformity, axial analysis, and fault interpretation. The results of this study indicate a regime of episodic growth of the western Kunlun Mountains and Tarim Basin during the Cenozoic.

  3. Microendemicity in the northern Hajar Mountains of Oman and the United Arab Emirates with the description of two new species of geckos of the genus Asaccus (Squamata: Phyllodactylidae)

    PubMed Central

    Jayasinghe, Sithum; Wilms, Thomas; Els, Johannes

    2016-01-01

    Background The Hajar Mountains of Oman and the United Arab Emirates (UAE) is the highest mountain range in Eastern Arabia. As a result of their old geological origin, geographical isolation, complex topography and local climate, these mountains provide an important refuge for endemic and relict species of plants and animals with strong Indo-Iranian affinities. Among vertebrates, the rock climbing nocturnal geckos of the genus Asaccus represent the genus with the highest number of endemic species in the Hajar Mountains. Recent taxonomic studies on the Zagros populations of Asaccus have shown that this genus is much richer than it was previously thought and preliminary morphological and molecular data suggest that its diversity in Arabia may also be underestimated. Methods A total of 83 specimens originally classified as Asaccus caudivolvulus (including specimens of the two new species described herein), six other Asaccus species from the Hajar and the Zagros Mountains and two representatives of the genus Haemodracon were sequenced for up to 2,311 base pairs including the mitochondrial 12S and cytb and the nuclear c-mos, MC1R and ACM4 genes. Phylogenetic relationships were inferred using both Bayesian and maximum-likelihood approaches and the former method was also used to calibrate the phylogenetic tree. Haplotype networks and phylogenetic trees were inferred from the phased nuclear genes only. Sixty-one alcohol-preserved adult specimens originally classified as Asaccus caudivolvulus from the northern Hajar Mountains were examined for 13 morphometric and the five meristic variables using multivariate methods and were also used to diagnose and describe the two new species. Results The results of the molecular and morphological analyses indicate that the species originally classified as Asaccus caudivolvulus is, in fact, an assemblage of three different species that started diversifying during the Mid-Miocene. The molecular phylogenies consistently recovered the Hajar

  4. Organosulfates and Carboxylic Acids in Secondary Organic Aerosols in Coniferous Forests in Rocky Mountains (USA), Sierra Nevada Mountains (USA) and Northern Europe (Finland and Denmark)

    NASA Astrophysics Data System (ADS)

    Glasius, M.; Hansen, A. M. K.; Kristensen, K.; Kristensen, T. B.; Mccubbin, I. B.; Hallar, A. G.; Petäjä, T.; Surratt, J. D.; Worton, D. R.; Bilde, M.; Kulmala, M. T.; Goldstein, A. H.

    2014-12-01

    Levels and chemical composition of secondary organic aerosols affect their climate effects and properties. Organosulfates (OS) are formed through heterogeneous reactions involving oxidized sulfur compounds, primarily originating from anthropogenic sources. Availability of authentic standards have until now been an obstacle to quantitative investigations of OS in atmospheric aerosols. We have developed a new, facile method for synthesis and purification of OS standards. Here we have used 7 standards to quantify OS and nitrooxy organosulfates (NOS) observed in aerosols collected at four sites in coniferous forests in USA and Europe during spring or summer. The two American sites were Storm Peak Laboratory, Colorado (Rocky Mountains, elevation 3220 m a.s.l) and Sierra Nevada Mountains, California (as part of BEARPEX 2007 and 2009). The European sites were Hyytiälä Forest Station, Finland (in the boreal zone) and Silkeborg, Denmark (temperate forest). Aerosol filter samples were extracted and analyzed using a high performance liquid chromatograph coupled through an electrospray inlet to a quadrupole time-of-flight mass spectrometer (HPLC-QTOF-MS). We identified 11 carboxylic acids using authentic standards, while 16 different OS and 8 NOS were identified based on their molecular mass and MS fragmentation patterns, as well as comparison with available standards. OS were ubiquitous in the atmospheric aerosol samples, even at the high elevation mountain station. Levels of carboxylic acids from oxidation of monoterpenes were 8-25 ng m-3 at Silkeborg and Storm Peak Laboratory, while concentrations at the sites with strong regional monoterpene emissions (Sierra Nevada Mountains and Hyytiälä) were much higher (10-200 ng m-3). At all sites, the dominant group of OS were derived from isoprene (IEPOX) and related compounds, while OS of monoterpenes showed lower concentrations, except at Hyytiälä during periods of north-westerly winds when monoterpene OS were at similar or

  5. Heterogeneous extrusion and exhumation of deep-crustal Variscan assembly: Geochronology of the Western Tatra Mountains, northern Slovakia

    NASA Astrophysics Data System (ADS)

    Moussallam, Y.; Schneider, D. A.; Janák, M.; Thöni, M.; Holm, D. K.

    2012-07-01

    The nature and style of mid-crustal assembly and exhumation during continental collision has been investigated in the Tatra Mountains of the Western Carpathians. The pre-Alpine basement of the Western Carpathians represents the easternmost exposure of the Variscan orogen in Europe, which marks the collision of Laurasia with Gondwanian-affiliated terranes during the Palaeozoic. The Tatric crystalline unit of the Western Tatra in northern Slovakia displays an inverted metamorphic sequence where a high-grade unit comprising migmatites with relicts of eclogite has been thrust over a lower-grade mica schist unit. New geochronological and thermochronological data together with published thermobarometry illuminate the metamorphic history of the Western Tatra. The Upper Unit eclogites with occasionally preserved omphacite record near isothermal decompression from 1.6 GPa to 1.0-1.2 GPa at 750-800 °C which lead to intensive re-equilibration at high-pressure granulite facies conditions, comparable to the peak metamorphic conditions of the host migmatite. Both eclogite and migmatite shared a retrograde P-T path following the insertion of the eclogite assemblage into the migmatites. The metamorphic evolution of the Lower Unit mica schist is constrained to peak P-T conditions of 0.6-0.8 GPa and 640 and 660 °C followed by retrogression. This suggests that different rock types of the Western Tatra metamorphic core shared only their exhumation path from mid-crustal levels. ID-TIMS Sm-Nd dating of garnet from eclogite yields a whole rock-garnet isochron age of 337 ± 10 Ma, with an initial ɛNd isotopic composition of + 8.3. In situ U-Pb dating of monazite from a migmatite surrounding the eclogite shows one age population of c. 380 Ma whereas monazite from a migmatite away from the eclogite preserves a robust 340 ± 11 Ma age which is indistinguishable from Sm-Nd garnet age and U-Pb age of zircons in the anatectic leucosome of the migmatite (347 ± 7 Ma). A younger monazite age

  6. Geologic structure and altitude of the top of the Minnelusa Formation, northern Black Hills, South Dakota and Wyoming, and Bear Lodge Mountains, Wyoming

    USGS Publications Warehouse

    Peter, Kathy D.; Kyllonen, David P.; Mills, K.R.

    1987-01-01

    Beginning in 1981, a 3-yr project was conducted to determine the availability and quality of groundwater in the sedimentary bedrock aquifers in the Black Hills of South Dakota and Wyoming. The project was limited to three bedrock units in order of increasing age: the Cretaceous Inyan kara Group, Permian and Pennsylvanian Minnelusa Formation, and Mississippian Madison (or Pahasapa) Limestone. This map shows the altitude of the top of the Minnelusa Formation in the northern Black Hills, and shows the configuration of the structural features in the northern part of the Black Hills and the eastern part of the Bear Lodge Mountains. In general, the Minnelusa Formation dips away from the Black Hills uplift, either to the northeast and the Williston Basin or, south of the Bear Lodge Mountains, to the southwest and the Powder River basin, which is outside the map area. In the map area, the upper beds of the Minnelusa Formation are an aquifer and the lower beds are a confining or semi-confining unit. The upper part of the Minnelusa Formation has a greater percentage of coarse-grained sandstone beds than the lower part. Furthermore, solution and removal of anhydrite, brecciation, and solution of cement binding the sandstone grains may have increased the permeability of the upper part of the Minnelusa Formation in the Black Hills. Wells completed in the upper part of the Minnelusa have yields that exceed 100 gal/min in some areas and at least one large diameter well is reported to flow 1,000 gal/min in some areas and at least one large diameter well is reported to flow 1,000 gal/min. Flowing wells have been completed in the Minnelusa aquifer in most of the study area in South Dakota and in about the northern one-half of Crook County, Wyoming. (Lantz-PTT)

  7. Geohydrology and water quality of the Inyan Kara, Minnelusa, and Madison aquifers of the northern Black Hills, South Dakota and Wyoming, and Bear Lodge Mountains, Wyoming

    USGS Publications Warehouse

    Kyllonen, D.P.; Peter, K.D.

    1987-01-01

    The Inyan Kara, Minnelusa, and Madison aquifers are the principal sources of ground water in the northern Black Hills, South Dakota and Wyoming, and Bear Lodge Mountains, Wyoming. The aquifers are exposed in the Bear Lodge Mountains and the Black Hills and are about 3,000 to 5,000 ft below the land surface in the northeast corner of the study area. The direction of groundwater movement is from the outcrop area toward central South Dakota. Recharge is by infiltration of precipitation and streamflow is by springs and well withdrawals. All three aquifers yield water to flowing wells in some part of the area. Measured and reported well yields in each of the three aquifers exceed 100 gal/min (gpm). A well open to the Minnelusa Formation and the upper part of the Madison Limestone yielded more than 2 ,000 gpm. Water from the Inyan Kara aquifer may require treatment for gross alpha radiation, iron, manganese, sulfate, and hardness before use in public water systems. Water from the Minnelusa aquifer in the northern one-half of the study area may require treatment for sulfate and hardness before use in public water systems. Water from the Madison aquifer in the northern one-half of the study area may require treatment of fluoride, gross alpha radiation, sulfate, and hardness before use in public water systems. Water from the Minnelusa and Madison aquifers in the southern one-half of the study area, though very hard (more than 180 mg/L hardness as calcium carbonate), is suitable for public water systems and irrigation. Flow between the Minnelusa and the Inyan Kara aquifers appears to be insignificant, based on the results of a digital model results. The model indicated there may be significant recharge to the Minnelusa and Madison aquifers by leakage between these two aquifers and perhaps deeper aquifers. (Author 's abstract)

  8. Exploring the Effects of GCM Uncertainty on the Hydrology and Water Allocation of a Small Mountain Watershed in Northern British Columbia, Canada.

    NASA Astrophysics Data System (ADS)

    Hirshfield, F.; Anderson, A.; Sui, J.

    2014-12-01

    Climate change and allocation of water supplies are causing water shortages and low flow conditions that threaten aquatic ecosystems around the world. Small mountain streams in Western Canada are experiencing increased water use from small diversion hydropower, increasing population, mining, agriculture, and changing energy extraction techniques. In addition, there are very few gauging sites for baseline water data because of the rugged mountain terrain and cold climate. Baseline data is important due to the sensitivity of small mountain streams to shifts in timing of snow pack melt and mid-winter melting, especially near and in coastal regions. Here we use HBV-EC to simulate the range in future flow in a northern mountain watershed under various climate scenarios and explore the uncertainty induced by different GMC models and downscaling for the Goathorn Creek watershed. To explore the effects of GCM model variability we selected four models (CGCM3, ECHAM5, GFDL-CM2.1, and CSIRO-Mk) and used the TreeGen downscaling method to generate multiple ensembles for emissions scenarios (A1B, A2 and B1) for each GCM model. The calibrated HBV-EC model was sensitive to the climate inputs and produced a 50 percent variation in flows for the 2050's and 2080's with the greatest reduction in mean flows by 0.33 m3/s predicted for the 2020's climate. Although, modeled future discharge is highly variable, some consistent trends are useful for water managers: results suggest spring discharge may occur up to two months earlier (CGCM3, A2 scenario), but was constantly one month earlier for all emission scenarios. This can lead to feasible management strategies such as granting fewer water permits or in areas with high future demand issuing permits with provisions for future storage.

  9. The amphibians and reptiles of Luzon Island, Philippines, VIII: the herpetofauna of Cagayan and Isabela Provinces, northern Sierra Madre Mountain Range.

    PubMed

    Brown, Rafe M; Siler, Cameron D; Oliveros, Carl H; Welton, Luke J; Rock, Ashley; Swab, John; Weerd, Merlijn Van; van Beijnen, Jonah; Jose, Edgar; Rodriguez, Dominic; Jose, Edmund; Diesmos, Arvin C

    2013-01-01

    We provide the first report on the herpetological biodiversity (amphibians and reptiles) of the northern Sierra Madre Mountain Range (Cagayan and Isabela provinces), northeast Luzon Island, Philippines. New data from extensive previously unpublished surveys in the Municipalities of Gonzaga, Gattaran, Lasam, Santa Ana, and Baggao (Cagayan Province), as well as fieldwork in the Municipalities of Cabagan, San Mariano, and Palanan (Isabela Province), combined with all available historical museum records, suggest this region is quite diverse. Our new data indicate that at least 101 species are present (29 amphibians, 30 lizards, 35 snakes, two freshwater turtles, three marine turtles, and two crocodilians) and now represented with well-documented records and/or voucher specimens, confirmed in institutional biodiversity repositories. A high percentage of Philippine endemic species constitute the local fauna (approximately 70%). The results of this and other recent studies signify that the herpetological diversity of the northern Philippines is far more diverse than previously imagined. Thirty-eight percent of our recorded species are associated with unresolved taxonomic issues (suspected new species or species complexes in need of taxonomic partitioning). This suggests that despite past and present efforts to comprehensively characterize the fauna, the herpetological biodiversity of the northern Philippines is still substantially underestimated and warranting of further study. PMID:23653519

  10. The amphibians and reptiles of Luzon Island, Philippines, VIII: the herpetofauna of Cagayan and Isabela Provinces, northern Sierra Madre Mountain Range

    PubMed Central

    Brown, Rafe M.; Siler, Cameron D.; Oliveros, Carl. H; Welton, Luke J.; Rock, Ashley; Swab, John; Weerd, Merlijn Van; van Beijnen, Jonah; Jose, Edgar; Rodriguez, Dominic; Jose, Edmund; Diesmos, Arvin C.

    2013-01-01

    Abstract We provide the first report on the herpetological biodiversity (amphibians and reptiles) of the northern Sierra Madre Mountain Range (Cagayan and Isabela provinces), northeast Luzon Island, Philippines. New data from extensive previously unpublished surveys in the Municipalities of Gonzaga, Gattaran, Lasam, Santa Ana, and Baggao (Cagayan Province), as well as fieldwork in the Municipalities of Cabagan, San Mariano, and Palanan (Isabela Province), combined with all available historical museum records, suggest this region is quite diverse. Our new data indicate that at least 101 species are present (29 amphibians, 30 lizards, 35 snakes, two freshwater turtles, three marine turtles, and two crocodilians) and now represented with well-documented records and/or voucher specimens, confirmed in institutional biodiversity repositories. A high percentage of Philippine endemic species constitute the local fauna (approximately 70%). The results of this and other recent studies signify that the herpetological diversity of the northern Philippines is far more diverse than previously imagined. Thirty-eight percent of our recorded species are associated with unresolved taxonomic issues (suspected new species or species complexes in need of taxonomic partitioning). This suggests that despite past and present efforts to comprehensively characterize the fauna, the herpetological biodiversity of the northern Philippines is still substantially underestimated and warranting of further study. PMID:23653519

  11. Knickzone propagation in the Black Hills and northern High Plains: a different perspective on the late Cenozoic exhumation of the Laramide Rocky Mountains

    USGS Publications Warehouse

    Zaprowski, Brent J.; Evenson, Edward B.; Pazzaglia, Frank J.; Epstein, Jack B.

    2001-01-01

    Geomorphic research in the Black Hills and northern High Plains poses an intriguing hypothesis for the Cenozoic evolution of this salient of the Laramide Rockies. Most recently, geologists have appealed to late Cenozoic epeirogenic uplift or climate change to explain the post-Laramide unroofing of the Rockies. On the basis of field mapping and the interpretation of long-valley profiles, we conclude that the propagation of knickzones is the primary mechanism for exhumation in the Black Hills. Long profiles of major drainages show discrete breaks in the slope of the channel gradient that are not coincident with changes in rock type. We use the term knickzones to describe these features because their profiles are broadly convex over tens of kilometers. At and below the knickzone, the channel is incising into bedrock, abandoning a flood plain, and forming a terrace. Above the knickzone, the channel is much less incised, resulting in a broad valley bottom. Numerous examples of stream piracy are documented, and in each case, the capture is recorded in the same terrace level. These observations are consistent with migrating knickzones that have swept through Black Hills streams, rearranging drainages in their wake. We demonstrate there are two knickzone fronts associated with mapped terraces. Preliminary field evidence of soil development shows that these terraces are time transgressive in nature. Our data strongly suggest that knickzone propagation must be considered a viable mechanism driving late Cenozoic fluvial incision and exhumation of the northern High Plains and adjacent northern Rocky Mountains.

  12. Study of the extensive air shower mass sensitive parameters in prototype of ALBORZ array

    NASA Astrophysics Data System (ADS)

    Rastegarzadeh, G.; Nemati, M.

    2015-03-01

    In this work we have used muon production depth distribution as well as the lateral distribution of the secondary particles of Extensive Air Showers (EAS) as two main parameters to infer the mass composition of primary cosmic rays. In order to achieve a realistic estimate of the mass composition, a sample of showers initiated by proton and iron particles as primaries have been simulated by CORSIKA code with zenith angle between 0° and 18° and discrete energies in a range between 1014 and 1016 eV for ALBORZ (1200 m a.s.l, Tehran, Iran) and KASKADE (110 m a.s.l, Karlsruhe, Germany) observation levels. Moreover lateral density distribution functions of energy for charged particles of air showers have been proposed for both proton and Iron primaries. We have indicated that among these two EAS parameters, lateral distribution of secondary particles provides better mass discrimination.

  13. Late Quaternary landscape evolution in the Kunlun Mountains and Qaidam Basin, Northern Tibet: A framework for examining the links between glaciation, lake level changes and alluvial fan formation

    USGS Publications Warehouse

    Owen, L.A.; Finkel, R.C.; Haizhou, M.; Barnard, P.L.

    2006-01-01

    The Qaidam Basin in Northern Tibet is one of the largest hyper-arid intermontane basins on Earth. Alluvial fans, pediment surfaces, shorelines and a thick succession of sediments within the basin, coupled with moraines and associated landforms in the adjacent high mountain catchments of the Kunlun Mountains, record a complex history of Late Quaternary paleoenvironmental change and landscape evolution. The region provides an ideal natural laboratory to examine the interaction between tectonics and climate within a continent-continent collision zone, and to quantify rates of landscape evolution as controlled by climate and the associated glacial and hydrological changes in hyper-arid and adjacent high-altitude environments. Geomorphic mapping, analysis of landforms and sediments, and terrestrial cosmogenic radionuclide surface exposure and optically stimulated luminescence dating serve to define the timing of formation of Late Quaternary landforms along the southern and northwestern margins of the Qaidam Basin, and in the Burhan Budai Shan of the Kunlun Mountains adjacent to the basin on the south. These dates provide a framework that suggests links between climatic amelioration, deglaciation, lake desiccation and alluvial fan evolution. At least three glacial advances are defined in the Burham Budai Shan of the Kunlun Mountains. On the northern side of this range these occurred in the penultimate glacial cycle or early in the last glacial cycle, during the Last Glacial Maximum (LGM)/Lateglacial and during the Holocene. On the south side of the range, advances occurred during the penultimate glacial cycle, MIS-3, and possibly the LGM, Lateglacial or Holocene. Several distinct phases of alluvial fan sedimentation are likewise defined. Alluvial fans formed on the southern side of the Kunlun Mountains prior to 200 ka. Ice-contact alluvial fans formed during the penultimate glacial and during MIS-3. Extensive incised alluvial fans that form the main valley fills north of

  14. Seven Post-Pennsylvanian Structural Events in the Dry Hills and Northern Osgood Mountains: Evidence of Late Paleozoic Tectonism and New Getchell Fault Offset Data

    NASA Astrophysics Data System (ADS)

    Taylor, W. J.; Siebenaler, S.; Cashman, P.; Trexler, J.; Davydov, V.

    2008-12-01

    An incomplete understanding of the number and style of deformational events in north-central Nevada complicate economic and stratigraphic studies. To help unravel this structural history, we mapped and measured structures in the Dry Hills, northern Osgood Mountains, Humboldt County, Nevada. This research identified at least seven Pennsylvanian age or younger deformational events. The location was selected because it contains the Roberts Mountain allochthon (RMA), the Pennsylvanian (IP) to Permian (P) age Etchart Formation that was deposited atop the RMA, and the Golconda allochthon (GA). Measured folds and faults provide evidence of at least four deformational events that occurred between emplacement of the RMA and GA. Evidence for Late Paleozoic deformational events was recently well documented in other regional locations, but this location is farther north than previous studies. This research is also important because it provides information about the style and regional extent of these tectonic events. Structural mapping and data analysis reveal that the Etchart Formation contains four upright fold sets (SE-, NNW-, SSW-, NE-trending, in chronologic order) and three fault sets (N-striking normal, ENE-striking thrust, NNE-striking thrust), which may relate to the three youngest fold sets. The relative ages of the folds and faults are constrained via cross-cutting relationships, overprinting, and the oldest fold set being confined solely to the lowest stratigraphic unit within the Etchart Formation. These structures developed prior to and during emplacement of the GA. Two angular unconformities, the C5 and P1 angular unconformities of Trexler et al. (2003), are newly recognized in the area. The SW-trending fold set underlies the C5 unconformity. The P1 unconformity is angular indicating a deformational event and has been confirmed with fusulinid-based ages. The P1 and C5 unconformities correlate to other locations in northern Nevada implying regional scale late

  15. Meteorites constrain the age of Antarctic ice at the Frontier Mountain blue ice field (northern Victoria Land)

    NASA Astrophysics Data System (ADS)

    Folco, L.; Welten, K. C.; Jull, A. J. T.; Nishiizumi, K.; Zeoli, A.

    2006-08-01

    We show that meteorites can provide chronological constraints upon the age of the ice cropping out at the Frontier Mountain meteorite trap (Antarctica) when their terrestrial age is placed in a glaciological context. Amongst the over 700 meteorites found so far, Frontier Mountain (FRO) 84001, 99028, 93005 and 93054 were most likely not wind-drifted across the ice field, since their masses (772-1665 g) are much heavier than the local ˜ 200 g wind transport threshold. The four meteorites were found along a stretch of ice where a representative section of the Frontier Mountain blue ice crops out. Based on the bedding of englacial tephra layers, the structure of the ice along the section appears to be essentially an up-glacier dipping monocline. The 14C terrestrial age of FRO 8401, 99028 and 93005 are 13 ± 2, 21 ± 3 and 27 ± 2 ky, respectively; the 41Ca/ 36Cl age of FRO 93054 is 40 ± 10 ky. The terrestrial ages of the four meteorites increase from the top to the bottom layers of the monocline. This geographic distribution is best explained by delivery of meteorites at the ice surface through the "ice-flow model" (i.e., englacial transport from the snow accumulation zone and exhumation in the blue ice area through ablation) rather than direct fall. Since the effect of ablation in decoupling terrestrial ages of meteorites and the age of the ice on which they sit must have been minor (most likely ≤ 7 ky) based on the local ice dynamics, we conclude that the age of the bulk of the ice body currently under ablation at Frontier Mountain is up to ˜ 50 ky old. This result has implications on both the meteorite concentrations mechanism at Frontier Mountain and the regional ice dynamics.

  16. Trace-metal concentrations, waters from selected sky lakes, streams and springs, northern Shawangunk Mountains, New York: geologic and ecologic implications

    USGS Publications Warehouse

    Friedman, J.D.; Huth, P.C.; Smiley, D.

    1990-01-01

    Reconnaissance sampling and chemical analysis of water from selected lakes, streams and springs of the northern Shawangunk Mountains in 1987 to 1988 to determine the influence of lithology on trace-metal concentrations in surface water, and to establish a base level of concentration of 27 selected metals by ICP-AES and Hg by cold-vapor AAS methods, for geochemical exploration, ecologic, acid-rain, and climatic-change studies, have yielded trace-metal concentrations greater than detection limits for 10 metallic elements. Eighteen additional metallic elements were also present in trace quantities below the quantitative detection limit. Two distinct geochemical populations are related to source lithology and pH. -from Authors

  17. Holocene environmental changes inferred from biological and sedimentological proxies in a high elevation Great Basin lake in the northern Ruby Mountains, Nevada, USA

    USGS Publications Warehouse

    Wahl, David B.; Starratt, Scott W.; Anderson, Lysanna; Kusler, Jennifer E.; Fuller, Christopher C.; Addison, Jason A.; Wan, Elmira

    2015-01-01

    Multi-proxy analyses were conducted on a sediment core from Favre Lake, a high elevation cirque lake in the northern Ruby Mountains, Nevada, and provide a ca. 7600 year record of local and regional environmental change. Data indicate that lake levels were lower from 7600-5750 cal yr BP, when local climate was warmer and/or drier than today. Effective moisture increased after 5750 cal yr BP and remained relatively wet, and possibly cooler, until ca. 3750 cal yr BP. Results indicate generally dry conditions but also enhanced climatic variability from 3750-1750 cal yr BP, after which effective moisture increased. The timing of major changes in the Favre Lake proxy data are roughly coeval and in phase with those recorded in several paleoclimate studies across the Great Basin, suggesting regional climatic controls on local conditions and similar responses at high and low altitudes.

  18. National coal resource assessment non-proprietary data: Location, stratigraphy, and coal quality for selected tertiary coal in the Northern Rocky Mountains and Great Plains region

    USGS Publications Warehouse

    Flores, Romeo M.; Ochs, A.M.; Stricker, G.D.; Ellis, M.S.; Roberts, S.B.; Keighin, C.W.; Murphy, E.C.; Cavaroc, V.V., Jr.; Johnson, R.C.; Wilde, E.M.

    1999-01-01

    One of the objectives of the National Coal Resource Assessment in the Northern Rocky Mountains and Great Plains region was to compile stratigraphic and coal quality-trace-element data on selected and potentially minable coal beds and zones of the Fort Union Formation (Paleocene) and equivalent formations. In order to implement this objective, drill-hole information was compiled from hard-copy and digital files of the: (1) U.S. Bureau of Land Management (BLM) offices in Casper, Rawlins, and Rock Springs, Wyoming, and in Billings, Montana, (2) State geological surveys of Montana, North Dakota, and Wyoming, (3) Wyoming Department of Environmental Quality in Cheyenne, (4) U.S. Office of Surface Mining in Denver, Colorado, (5) U.S. Geological Survey, National Coal Resource Data System (NCRDS) in Reston, Virginia, (6) U.S. Geological Survey coal publications, (7) university theses, and (8) mining companies.

  19. Historical patterns of western spruce budworm and douglas-fir tussock moth outbreaks in the northern Blue Mountains, Oregon, since a.d. 1700. Forest Service research paper

    SciTech Connect

    Swetnam, T.W.; Wickman, B.E.; Paul, H.G.; Baisan, C.H.

    1995-10-01

    Tree-ring samples from 21 mixed-conifer stands in the Blue Mountains of northeastern Oregon were analyzed for evidence of past western spruce budworm and Douglas-fir tussock moth outbreaks. Comparison of host and nonhost tree-ring growth provided an objective basis for distinguishing climatic effects from insect defoliation effects. Our reconstruction shows that since ca. A.D. 1700 at least eight regional budworm outbreaks occurred at intervals of about 21 to 53 years. Reduced radial growth periods caused by defoliation lasted from 13 to 17 years. Two regional budworm out-breaks occurred in the 19th century (ca. 1806 to 1822 and ca. 1851 to 1867), three outbreaks occurred in the northern Blue Mountains in the 20th century (ca. 1898 to 1910, ca. 1946 to 1958, and ca. 1980 to present), and an additional outbreak occurred in the Eagle Cap Wilderness (ca. 1925 to 1939). These findings generally lend support to the hypothesis that budworm outbreaks have increased in frequency and severity in the 20th century in northeastern Oregon.

  20. Assessment and monitoring of recreation impacts and resource conditions on mountain summits: examples from the Northern Forest, USA

    USGS Publications Warehouse

    Monz, Christopher A.; Marion, Jeffrey L.; Goonan, Kelly A.; Manning, Robert E.; Wimpey, Jeremy; Carr, Christopher

    2010-01-01

    Mountain summits present a unique challenge to manage sustainably: they are ecologically important and, in many circumstances, under high demand for recreation and tourism activities. This article presents recent advances in the assessment of resource conditions and visitor disturbance in mountain summit environments, by drawing on examples from a multiyear, interdisciplinary study of summits in the northeastern United States. Primary impact issues as a consequence of visitor use, such as informal trail formation, vegetation disturbance, and soil loss, were addressed via the adaption of protocols from recreation ecology studies to summit environments. In addition, new methodologies were developed that provide measurement sensitivity to change previously unavailable through standard recreation monitoring protocols. Although currently limited in application to the northeastern US summit environments, the methods presented show promise for widespread application wherever summits are in demand for visitor activities.

  1. Geo-archaeological investigations of Palaeolithic sites along the Ural Mountains - On the northern presence of humans during the last Ice Age

    NASA Astrophysics Data System (ADS)

    Svendsen, John Inge; Heggen, Herbjørn Presthus; Hufthammer, Anne Karin; Mangerud, Jan; Pavlov, Pavel; Roebroeks, Wil

    2010-11-01

    We review geo-archaeological results from six Palaeolithic sites along the western flank of the northern Ural Mountains. The oldest traces of human activities, dated to around 36-35 14C ka BP (43-40 cal ka), were found in alluvial strata at Mamontovaya Kurya at the Polar Circle - their connection to cultures further south remains uncertain. Slightly younger artefacts were found at the site Zaozer'e, nearly a thousand km further to the south, where a rich archaeological assemblage, dated to 34-33 14C ka BP (39-37 cal ka), was uncovered from underneath several meters of loess. The assemblage contains some small "Middle Palaeolithic like" bifaces alongside distinct Upper Palaeolithic traits, such as well-defined blades. This site also contains some perforated "pendants" made of freshwater molluscs. At the Byzovaya site, located at 65°N and radiocarbon dated to about 30-29 14C ka BP (34-32 cal ka), more than 300 artefacts and several thousand animal remains, mostly of mammoth, were incorporated in coarse-grained debris-flow deposits, sealed by aeolian sand. Pending the results from a new technological analysis of the whole artefact assemblage we can yet not decide whether Byzovaya should be categorized as a Middle- or Upper Palaeolithic site. The finds from Garchi, located in a loess sequence near Zaozer'e, have a similar or slightly younger age than the material from Byzovaya. Also at this site bifacial tools are present; alongside some characteristic triangle projectile points as well as some other elements which have nearly identical counterparts in the Upper Palaeolithic Kostenki/Streletskaya and Sungirian complexes, unambiguously associated with Modern humans. We conclude that the initial human colonisations along the Ural Mountains took place during a relatively favourable period of Marine Isotope Stage 3, when only small mountain glaciers existed in this region. The finds from the Medvezhia Peshera rock shelter have a completely different age (19-16 14C ka BP

  2. Influence of tectonic terranes adjacent to Precambrian Wyoming province of petroleum source and reservoir rock stratigraphy in northern Rocky Mountain region

    SciTech Connect

    Tonnsen, J.J.

    1984-07-01

    The perimeter of the Archean Precambrian Wyoming province can be generally defined. A Proterozoic suture belt separates the province from the Archean Superior province to the east. The western margin of the Precambrian rocks lies under the western Overthrust belt, but the Precambrian province extends at least as far west as southwest Montana and southeast Idaho. The province is bounded on the north and south by more regionally extensive Proterozoic mobile belts. In the northern belt, Archean rocks have been remobilized by Proterozoic tectonic events, but the southern belt does not appear to contain rocks as old as Archean. The tectonic response of these Precambrian terranes to cratonic and continental margin vertical and horizontal forces has exerted a profound influence on Phanerozoic sedimentation and stratigraphic facies distributions. Petroleum source rock and reservoir rock stratigraphy of the Northern Rocky Mountain region has been correlated with this structural history. In particular, the Devonian, Permian, and Jurassic sedimentation patterns can be shown to have been influenced by articulation among the different terranes comprising the ancient substructure. Depositional patterns in the Chester-Morrow carbonate and clastic sequence in the Central Montana trough are also related to this substructure. Further, a correlation between these tectonic terranes and the localization of regional hydrocarbon accumulations has been observed and has been useful in basin analyses for exploration planning.

  3. Silicic Volcanism at the Northern and Western Extent of the Columbia River Basalt Rhyolite Flare-up: Rhyolites of Dooley Mountain and Buchanan, Oregon

    NASA Astrophysics Data System (ADS)

    Large, A.; Streck, M. J.; Jenkins, E. N.; Ferns, M. L.

    2015-12-01

    Mid-Miocene (16.5-15 Ma) rhyolite volcanism associated with the eruption of lavas of the Columbia River Basalt Group (CRBG) stretches from NE Nevada to SW Idaho to NE Oregon over an area with about a 400 km diameter. Dooley Mountain and Buchanan rhyolite complexes are located along the northern termination near Baker City and along the western periphery near Burns of this rhyolite flare-up, respectively. Despite their importance for understanding co-genetic rhyolite volcanism to CRBG magmatism prior data on both complexes are sparse. Limited geochemical data exist only for Dooley Mountain and there is only one age date for either complex. Our ongoing study of both complexes is targeted to establish eruptive units and stratigraphy, to determine activity span, and to detail the petrology of rhyolite units by mapping or remapping key areas building on prior work (e.g., Evans, J. G., 1992, U.S.G.S. Map GQ-1694), by petrographic analysis and whole rock geochemistry, and by Ar-Ar geochronology. Both complexes are multi-phase, apparently long-lived centers that erupted mostly rhyolite lava flows and domes but locally derived pyroclastic units occur as well but are subordinate in volume. Rhyolite activity is currently pinned at 15.5-14.7 Ma at Dooley Mountain and at 16.1 Ma at Buchanan but is expected to be extending with more dating. Rhyolites range from aphyric to containing ~ 15% phenocrysts dominated by feldspar or quartz. Rhyolites range from low- to high-silica varieties and indicate variable degrees of differentiation as established by the following ranges for Ba, Sr, and Eu/Eu*, respectively: 1500-500, 200-75, 0.6-0.15 for Dooley Mountain and 1700-100, 250-8, 0.88-0.19 for Buchanan. In addition, preliminary data indicate rhyolites range in their affinity from calc-alkaline to more A-type rhyolites. We speculate that A-type varieties coincide in these peripheral rhyolite complexes with the peak of Grande Ronde Basalt activity that impacted the greater area.

  4. Peak discharges in steep mountain catchments in relation to rainfall variability, vegetation cover and geomorphology of the Rift Valley Escarpment of Northern Ethiopia

    NASA Astrophysics Data System (ADS)

    Gebreyohannes, Tesfaalem; Frankl, Amaury; Haile, Mitiku; Abraha, Amanuel; Monsieurs, Elise; Nyssen, Jan

    2015-04-01

    The hydrological characteristics of steep mountain streams are often considered to be mainly influenced by rainfall distribution and topography. In this study, with the objective of analyzing the runoff response of mountain catchments, a total of 340 peak stage discharges were recorded in three rainy seasons (2012-2014) in 11 sloping (27-65%) mountain catchments (0.4 - 25 km²) of the marginal western Rift Valley escarpment of Northern Ethiopia. Daily rainfall data were collected using 7 rain gauges installed at different altitudes (1623 - 2851 m a.s.l) in and nearby the catchments, and used to calculate weighted average daily rain depths over the catchments. Event peak discharges were calculated from daily measurements by 11 crest stage gauges using the Manning's equation. Percentages of land use and cover classes were detected from high resolution (0.6 m) Google Earth imagery (February 1, 2014). Morphometric characteristics of the catchments were computed from ASTER digital elevation model and topographic maps. Correlation analysis between daily rainfall and peak discharge showed direct relationship (R² = 0.5-0.94, P<0.01) in all the catchments. The average specific peak discharge was negatively related to percentage of forest and grass cover (R² = 0.64, P<0.01), time of concentration (R² = 0.31, P<0.01), drainage texture (R² = 0.42, P<0.01), and catchment perimeter (R² = 0.36, P<0.01). The specific peak discharge was positively correlated with average slope gradient of the catchments (R² = 0.34, P<0.01) and with an index representing the spatial distribution of forest and grass cover (R² = 0.43, P<0.01). A stepwise multiple regression analyses showed that 84% (P<0.01) of the variability of the runoff response in the catchments can be predicted by the percentage of forest and grass cover and the relief ratio of the catchments. All in all, this study demonstrates that the magnitude of flash floods in mountain catchments is not only influenced by the

  5. Crustal structure of Wrangellia and adjacent terranes inferred from geophysical studies along a transect through the northern Talkeetna Mountains

    USGS Publications Warehouse

    Glen, J.M.G.; Schmidt, J.; Pellerin, L.; McPhee, D.K.; O'Neill, J. M.

    2007-01-01

    Recent investigations of the Talkeetna Mountains in south-central Alaska were undertaken to study the region's framework geophysics and to reinterpret structures and crustal composition. Potential field (gravity and magnetic) and magnetotelluric (MT) data were collected along northwest-trending profiles as part of the U.S. Geological Survey's Talkeetna Mountains transect project. The Talkeetna Mountains transect area comprises eight 1:63,360 quadrangles (???9500 km2) in the Healy and Talkeetna Mountains 1?? ?? 3?? sheets that span four major lithostratigraphic terranes (Glen et al., this volume) including the Wrangellia and Peninsular terranes and two Mesozoic overlap assemblages inboard (northwest) of Wrangellia. These data were used here to develop 21/2-dimensional models for the three profiles. Modeling results reveal prominent gravity, magnetic, and MT gradients (???3.25 mGal/ km, ???100nT/km, ???300 ohm-m/km) corresponding to the Talkeetna Suture Zone-a first-order crustal discontinuity in the deep crust that juxtaposes rocks with strongly contrasting rock properties. This discontinuity corresponds with the suture between relatively dense magnetic crust of Wrangellia (likely of oceanic composition) and relatively less dense transitional crust underlying Jurassic to Cretaceous flysch basins developed between Wrangellia and North America. Some area of the oceanic crust beneath Wrangellia may also have been underplated by mafic material during early to mid-Tertiary volcanism. The prominent crustal break underlies the Fog Lakes basin approximately where theTalkeetna thrust faultwaspreviouslymappedas a surface feature. Potential fieldand MT models, however, indicate that the Talkeetna Suture Zone crustal break along the transect is a deep (2-8 km), steeply west-dipping structure-not a shallow east-dipping Alpine nappe-like thrust. Indeed, most of the crustal breaks in the area appear to be steep in the geophysical data, which is consistent with regional geologic

  6. Two new species of Zospeum Bourguignat, 1856 from the Basque-Cantabrian Mountains, Northern Spain (Eupulmonata, Ellobioidea, Carychiidae)

    PubMed Central

    Jochum, Adrienne; de Winter, Anton J.; Weigand, Alexander M.; Gómez, Benjamín; Prieto, Carlos

    2015-01-01

    Abstract Two new species of the genus Zospeum Bourguignat, 1856 are described from caves in the Sierra de Aitzgorri (Gipuzkoa) and the Sierra Salvada (Burgos) in Northern Spain. The taxa Zospeum vasconicum sp. n. and Zospeum zaldivarae sp. n. have recently, without a formal name, been included in a molecular study of worldwide members of the Carychiidae. In the present paper, the shell morphology and variation of these species is described and illustrated. PMID:25755625

  7. The March 11, 2002 Masafi, United Arab Emirates Earthquake: Insights into the Seismotectonics of the Northern Oman Mountains

    SciTech Connect

    Rodgers, A; Fowler, A; Al-Amri, A; Al-Enezi, A

    2005-04-26

    A moderate (M{approx}5) earthquake struck the northeastern United Arab Emirates (UAE) and northern Oman on March 11, 2002. The event was felt over a wide area of the northern Emirates and was accompanied by smaller (felt) events before and after the March 11 main shock. The event was large enough to be detected and located by global networks at teleseismic distances. We estimated focal mechanism and depth from broadband complete regional waveform modeling. We report a normal mechanism with a slight right-lateral strike-slip component consistent with the large-scale tectonics. The normal component suggests relaxation of obducted crust of the Semail Ophilite (specifically, the Khor Fakkan Block) while the right-lateral strike-slip component of the mechanism is consistent with shear across the Oman Line. Felt earthquakes are rare in the region, however no regional seismic network exists in the UAE to determine local seismicity. This event offers a unique opportunity to study the active tectonics of the region as well as inform future studies of seismic hazard in the UAE and northern Oman.

  8. MARBLE MOUNTAIN WILDERNESS, CALIFORNIA.

    USGS Publications Warehouse

    Donato, Mary M.; Hale, William N.

    1984-01-01

    The Marble Mountain Wilderness is located in the north-central Klamath Mountains of northern California. Geologic, geochemical, geophysical, and mineral investigations indicate that the wilderness has areas of probable and substantiated resource potential for placer gold, for chromite, and for marble. The geologic terrane precludes the occurrence of fossil fuel resources.

  9. Temporal and spatial constraints on the evolution of a Rio Grande rift sub-basin, Guadalupe Mountain area, northern New Mexico

    NASA Astrophysics Data System (ADS)

    Thompson, R. A.; Turner, K. J.; Cosca, M. A.; Drenth, B.; Hudson, M. R.; Lee, J.

    2013-12-01

    The Taos Plateau volcanic field (TPVF) in the southern San Luis Valley of northern New Mexico is the most voluminous of the predominantly basaltic Neogene (6-1 Ma) volcanic fields of the Rio Grande rift. Volcanic deposits of the TPVF are intercalated with alluvial deposits of the Santa Fe Group and compose the N-S-trending San Luis Basin, the largest basin of the northern rift (13,500 km2 in area). Pliocene volcanic rocks of the Guadalupe Mountain area of northern New Mexico are underlain by the southern end of one of the larger sub-basins of the San Luis Valley, the Sunshine sub-basin (~ 450 km2 in area) juxtaposed against the down-to-west frontal fault of the Precambrian-cored Sangre de Cristo Range. The sub-basin plunges northward and extends to near the Colorado-New Mexico border. The western margin (~15 km west of the Sangre de Cristo fault) is constrained by outcrops of Oligocene to Miocene volcanic rocks of the Latir volcanic field, interpreted here as a broad pre-Pliocene intra-rift platform underlying much of the northern TPVF. The southern sub-basin border is derived, in part, from modeling of gravity and aeromagnetic data and is interpreted as a subsurface extension of this intra-rift platform that extends southeastward to nearly the Sangre de Cristo range front. Broadly coincident with this subsurface basement high is the northwest-trending, curvilinear terminus of the down-to-northeast Red River fault zone. South of the gravity high, basin-fill alluvium and ~3.84 Ma Servilleta basalt lava flows thicken along a poorly exposed, down-to-south, basin-bounding fault of the northern Taos graben, the largest of the San Luis Valley sub-basins. The uppermost, western sub-basin fill is exposed along steep canyon walls near the confluence of the Rio Grande and the Red River. Unconformity-bound, lava flow packages are intercalated with paleo Red River fan alluvium and define six eruptive sequences in the Guadalupe Mountain area: (1) Guadalupe Mtn. lavas (dacite ~5

  10. Simulation and design of pre-ionization systems for Alborz tokamak

    NASA Astrophysics Data System (ADS)

    Shahshenas, Shiva; Amrollahi, Reza

    2015-04-01

    Alborz tokamak is an educational system for studying plasma phenomena in many physics and engineering experiments. A hot filament and a reverse discharge loop are used in the tokamak as the pre-ionization system. The hot cathode prepares a local initial electron density, then the reverse discharge loop trigger the ionization avalanche by means of inducing a toroidal electric field. The parameters of the hot filament are determined in order to produce the desired electron source. Filament temperature is simulated by using three-dimensional finite element method. The average values of filament temperature and electron density at the plasma core (at the end of pre-ionization process) were calculated and are about 2750 K and 1019 m-3, respectively. The resultant electron density and equivalent plasma resistivity due to reverse discharge loop are also calculated. In this paper, the simulation results, optimum structural style, the obtained parameters, the temperature of different parts of the filament and produced electron density are presented and discussed.

  11. Separation of intrinsic and scattering attenuation in the crust of central and eastern Alborz region, Iran

    NASA Astrophysics Data System (ADS)

    Farrokhi, M.; Hamzehloo, H.; Rahimi, H.; Allameh Zadeh, M.

    2016-04-01

    In this study, more than 380 local earthquakes (2 < ML < 4.5) have been used to estimate the direct-shear waves (Qd), coda (Qc), intrinsic (Qi) and scattering quality factor (QSc) in the crust of central and eastern Alborz region. The events were recorded by one temporary and two permanent networks. The quality factors of shear and coda waves have been individually estimated at different frequency bands by using coda normalization (CNM) method and single backscattering (SBS) method, respectively. Average frequency-dependent relationships have been estimated for Qd and Qc as 111 ± 4f0.85±0.04 and 112 ± 8f1.02±0.06, respectively. The intrinsic quality factor, Qi, has been separated from the scattering quality factor QSc by using individually estimated Qc and Qd values. The average frequency-dependent relationships of Qi and QSc have been calculated in the form of 108f1.00 and 784f0.56, respectively. The results of this study suggest that S-wave's attenuation (Qd-1) is dominated by the intrinsic attenuation. The attenuation of coda waves has been observed similar to the intrinsic attenuation, which indicates, the coda decay is mostly caused by the intrinsic attenuation. It has been observed that the scattering mean free path is frequency independent at frequencies greater than 6 Hz. The results of this study are similar to the tectonically active regions.

  12. Experiences on the development of a Community Based Early Warning System for mountain risks in northern Italy

    NASA Astrophysics Data System (ADS)

    Garcia, Carolina; Sterlacchini, Simone; de Amicis, Mattia; Fontana, Michele; Trozzi, Arianna; Frigerio, Ivan

    2010-05-01

    In the framework of the European project Mountain Risks (http://mountain-risks.eu/), one of the projects currently developed is a methodology to integrate risk management and evacuation emergency plans, focused on prevention as a key element for disaster risk reduction, applied in the Mountain Community Valtellina of Tirano, an area recurrently affected by several mountain hazards. Taking into account the actual state of disaster risk reduction initiatives in the study area, including the existence of a real time emergency plan based on GIS (Geographical Information Systems), DSS (Decision Support Systems), and ICT (Information & Communication Technology), but knowing the lack involvement of the general community in any of the preparation activities developed until the present and the lack of divulgation of the current emergency plan, it was decided that the methodology that could better adapt to the actual conditions of the study area would be a non structural Community Based Early Warning System (CBEWS). A CBEWS has been recognized by institutions as the UN and the INSDR, as an effective and important strategy for disaster risk reduction. This strategy is broadly used especially in developing countries and has proved its effectiveness in many disasters crisis all over the world. In spite of that, possibly for political and social reasons, there are really few applications of CBEWS in developed countries which has made the elaboration of this research project a particularly difficult process due to the lack of previous references with similar conditions to the one in the study area. Difficulties related to any multidisciplinary work which also involves the general community have been faced during the development of the project such as the differences in language (both the technical jargon of the different disciplines and the native language), time restrictions, the process of learning and adapting to different social structures, the process of contacting several

  13. Integrating Physical and Chemical Characteristics of Lakes into the Glacially Influenced Landscape of the Northern Cascade Mountains, Washington State, USA.

    PubMed

    Larson; Lomnicky; Hoffman; Liss; Deimling

    1999-09-01

    / A basic knowledge of the physical and chemical characteristics of lakes is needed by management to make informed decisions to protect water resources. In this study we investigated some of the physical and chemical characteristics of 58 lakes in alpine, subalpine, and forest vegetation zones in a natural area (North Cascades National Park Service Complex) between 1989 and 1993. The objectives of the study were to: (1) document the time of ice-out relative to lake elevation; (2) determine how a sharp climate gradient west and east of the hydrologic divide affected the time of ice-out for subalpine lakes; and (3) assess how lake water quality was associated with lake elevation, lake depth, and basin geology. As expected, lake ice-out times occurred earlier with decreasing elevation. East-slope subalpine lakes iced-out earlier than did west-slope subalpine lakes because the east slope of the study area was drier and warmer than the west slope. On average, the lakes were relatively cold, neutral in pH, and low in dissolved substances and concentrations of nitrogen and phosphorus. Although some shallow lakes (depth <10 m) exhibited the highest alkalinities, conductivities, and concentrations of phosphorus and nitrogen, most shallow lakes exhibited low values for these variables that were comparable to values observed in deep lakes. Geology did not play a major role in segregating the lakes based on water quality. Overall, lake temperature, pH, alkalinity, conductivity, and concentrations of total phosphorus and total Kjeldahl N increased with decreasing elevation. These changes in water quality with decreasing elevation in this temperate mountainous region corresponded with warmer air temperatures and increased vegetation biomass, soil depth and maturity, and dissolved substances and nutrients.KEY WORDS: Limnology; Mountain lakes; Water quality; North Cascades National Park Service Complex; National Park Servicehttp://link.springer-ny.com/link/service/journals/00267

  14. Zircon (U-Th)/He thermochronology of Neoproterozoic strata from the Mackenzie Mountains, Canada: Implications for the Phanerozoic exhumation and deformation history of the northern Canadian Cordillera

    NASA Astrophysics Data System (ADS)

    Powell, Jeremy; Schneider, David; Stockli, Daniel; Fallas, Karen

    2016-03-01

    Sedimentary strata of the Neoproterozoic Mackenzie Mountains Supergroup (MMSG) and Windermere Supergroup (WSG) occupy the cores of anticlines in the Mackenzie Mountains of the Canadian Cordilleran Foreland Belt. Stratigraphic and structural evidence suggest that these rocks have undergone several episodes of burial and unroofing relatively intact. We report single-grain detrital muscovite 40Ar/39Ar and zircon (U-Th)/He (ZHe) data from a suite of samples across the fold-thrust belt and the Neoproterozoic stratigraphic record. The strata have not reached high enough temperatures to reset the muscovite 40Ar/39Ar system, and instead our detrital muscovite data refine Tonian-Cryogenian depositional ages. Single-crystal ZHe dates range from 432 ± 35 to 46 ± 4 Ma, indicating that MMSG and WSG strata have not been heated sufficiently to fully reset the ZHe system. These factors make the Neoproterozoic strata an attractive natural laboratory to test the utility of the zircon radiation damage and annealing model on the quantification of thermal histories from detrital zircon populations that have accumulated radiation damage over long geologic timescales. Thermal modeling reveals that (1) a substantial sedimentary package was deposited following the Devonian and removed during Permo-Triassic cooling, and (2) the Cordilleran deformation front propagated through the study area from the Albian to the Paleocene, with a moderate increase in cooling rates between 75-67 Ma in the southwest and 60-55 Ma at the deformation front. Ultimately, relationships between radiation damage and helium diffusion kinetics in zircon explain substantial ZHe date dispersion and elucidate the temperature-time history of the northern Canadian Cordillera.

  15. [Species composition and community structure of a spruce-fir forest and a larch forest on the northern slope of Changbai Mountains, Northeast China].

    PubMed

    Kuang, Xu; Xing, Ding-Liang; Zhang, Zhao-Chen; Song, Hou-Juan; Wang, Yun-Yun; Fang, Shuai; Yuan, Zuo-Qiang; Ye, Ji; Lin, Fei; Wang, Xu-Gao; Hao, Zhan-Qing

    2014-08-01

    Spruce-fir forest is the best protected forest vegetation, while larch forest is intrazonal vegetation on the northern slope of Changbai Mountains. To further understand their species composition and community structure, we established a 4 hm2 forest permanent plot in each of these two forests in 2010. All free-standing plant species with DBH (diameter at breast height) ≥ 1 cm were mapped, tagged, and identified to species. The results showed that there were 9257 stems belonging to 8640 genotype individuals, 22 species, 6 genera and 12 families in the spruce-fir forest plot, while 4060 stems belonging to 3696 genotype individuals, 22 species, 8 genera and 16 families in the larch forest plot. Species composition in the two plots was very similar. Most of the species belonged to the Changbai Mountains plant flora. The analysis of species' importance values showed that there were dominant species in both communities. The spruce-fir forest was dominated by Abies nephrolepis and Larix olgensis, whose importance values accounted for 38.7% and 23.9% of the sum of importance values over all species in the plot, respectively. The larch forest was dominated solely by L. olgensis, whose importance value accounted for 61.9% of the sum of importance values over all species in the plot. Both forests were in good condition of regeneration and showed a reversed 'J' type in tree size distributions, at community level. However, different species showed different shapes in size distribution in the two forests. A. nephrolepis showed a reversed 'J' type size distribution in the spruce-fir forest, while L. olgensis with DBH ≥ 10 cm showed a hump-shaped distribution in the larch forest. Spatial distribution patterns of the main species changed differently with size class and spatial scales. Common species had different spatial distribution patterns in the two plots. PMID:25509062

  16. Diet and nutritional status among children 24–59 months by seasons in a mountainous area of Northern Vietnam in 2012

    PubMed Central

    Huong, Le Thi; Xuan, Le Thi Thanh; Phuong, Le Hong; Huyen, Doan Thi Thu; Rocklöv, Joacim

    2014-01-01

    Background Seasonal variation affects food availability. However, it is not clear if it affects dietary intake and nutritional status of children in Vietnam. Objectives This paper aims at examining the seasonal variation in nutrition status and dietary intake of children aged 24–59 months. Design A repeated cross-sectional study design was used to collect data of changes in nutritional status and diets of children from 24 to 59 months through four seasons in Chiem Hoa district, Tuyen Quang province, a predominately rural mountainous province of northern Vietnam. The quantitative component includes anthropometric measurements, 24 hours dietary recall and socio-economic characteristics. The qualitative component was conducted through focus group discussions (FGDs) with mothers of the children surveyed in the quantitative component. The purpose of FGDs was to explore the food habits of children during the different seasons and the behaviours of their mothers in relation to the food that they provide during these seasons. Results The prevalence of underweight among children aged 24–59 months is estimated at around 20–25%; it peaked in summer (24.9%) and reached a low in winter (21.3%). The prevalence of stunting was highest in summer (29.8%) and lowest in winter (22.2%). The prevalence of wasting in children was higher in spring and autumn (14.3%) and lower in summer (9.3%). Energy intake of children was highest in the autumn (1259.3 kcal) and lowest in the summer (996.9 kcal). Most of the energy and the nutrient intakes during the four seasons did not meet the Vietnamese National Institute of Nutrition recommendation. Conclusions Our study describes some seasonal variation in nutrition status and energy intake among children in a mountainous area northern Vietnam. Our study indicated that the prevalence of stunting and underweight was higher in summer and autumn, while the prevalence of wasting was higher in spring and autumn. Energy intake did not always meet

  17. Magnetic Fabric Investigations of the Sapinero Mesa and Fish Canyon Tuffs, Northern Part of the Southern Rocky Mountain Volcanic Field, Colorado

    NASA Astrophysics Data System (ADS)

    Harper, C.; Martin, M.; Geissman, J. W.

    2013-12-01

    Exposures of two laterally extensive ignimbrites in the northern part of the Southern Rocky Mountain Volcanic Field (SRMVF) allow examination of the emplacement mechanisms of these pyroclastic deposits as a function of deposition on irregular preexisting topography using magnetic fabric techniques. The Sapinero Mesa Tuff (28.19 × 0.03 Ma) was erupted from the San Juan/Uncompahgre Caldera Complex and the Fish Canyon tuff (ca. 28.02 × 0.16 Ma) was erupted from the La Garita caldera. These ignimbrites are major components of the SRMVF and were emplaced on highly irregular paleotopography. The Sapinero Mesa Tuff was emplaced directly on the late Eocene West Elk Breccia near and west of the Blue Mesa reservoir and directly on Precambrian crystalline rocks south of the Blue Mesa reservoir. The Fish Canyon Tuff was emplaced directly on Precambrian crystalline rocks south and southwest of Gunnison. Our study of these two ignimbrites is concentrated in the northern part of the SRMVF and examines how these deposits were emplaced on different topographic features. To date, a total of 16 sites in the Fish Canyon and Sapinero Mesa tuffs have been collected and analyzed for determination of magnetic fabrics through measurements of anisotropy of magnetic susceptibility (AMS). These samples are currently being analyzed for measurements of anisotropy of anhysteretic remanent magnetization (AARM). Initial analyses indicate transport directions that generally coincide with the inferred regional north-northwest transport direction. Additional sampling includes a greater spatial extent and a more focused method of collection with an emphasis on localities chosen with careful consideration of relationships to paleotopographic features present during emplacement of the ignimbrites. Specifically, we have selected linear features of varying scales with strikes that vary significantly from the regional, inferred transport directions. Our work provides a means to compare regional inferred

  18. Gravitational spreading of mountain ridges coeval with Late Weichselian deglaciation: impact on glacial landscapes in Tröllaskagi, northern Iceland

    NASA Astrophysics Data System (ADS)

    Coquin, Julien; Mercier, Denis; Bourgeois, Olivier; Cossart, Etienne; Decaulne, Armelle

    2015-01-01

    During the Late Weichselian deglaciation, the coastal mountains of northern central Iceland have experienced significant paraglacial readjustment processes in the form of conspicuous rock slope failures and deep-seated gravitational slope deformation (DSGSD). Local topographic slopes and ridges were deeply reshaped by these large scale paraglacial processes. Located on the eastern side of Skagafjörður, one of the largest fjords of northern Iceland, the Óslandshlíðarfjöll and Hnjúkar ridges (65°49N, 19°14W) exhibit geomorphic evidence of spectacular DSGDS. Several series of DSGSD-induced landforms such as crestal graben and troughs initiated by ridge-top splitting were investigated over a 30-km2 area. On the basis of geomorphological mapping we recognized: (i) a ridge-top splitting event mainly controlled by glacial debuttressing induced by a minimal 300 m lowering of the glacier surface in the Deildardalur valley; (ii) a rapid Late Weichselian deglaciation of the Deildardalur valley spanning a few thousands of years (ice-free stage probably reached around 14,000 years cal. BP); (iii) ridge-top splitting having an influence on large-scale glacial patterns by guiding and facilitating glacial erosion along ridge-top grabens, resulting in accelerated trough widening. Based on these interpretations, we propose an evolutionary sequence of both the kinematic stages of the DSGSD and the Late Weichselian deglaciation at the valley scale. This work provides new insights into (i) the patterns of the Late Weichselian deglaciation in the Skagafjörður area, especially in tributary valleys of the fjord, (ii) the timing of large-scale paraglacial ridge-top deformations in relation to the post-LGM deglaciation and (iii) the influence of paraglacial DSGSD features on large-scale glacial erosional patterns.

  19. Distribution pattern of metals in fluvial sediments in mountainous rural catchments: a case study in Northern Portugal

    NASA Astrophysics Data System (ADS)

    Reis, Anabela; Parker, Andrew; Alencoão, Ana

    2015-04-01

    The management of sediments-associated contaminants, concerning quality and quantity, in mountainous rivers is a pertinent issue; it is well known that mountainous rivers contribute with significant sedimentary loads, transported in short periods of time, in response to short precipitation episodes. Our contribution presents results of a research study developed in one of the tributaries of the River Douro, the River Corgo catchment (studied area of 295 km2). The River Corgo traverses Vila Real city and encounters the River Douro in Régua, in the West limit of the Douro Region - classified as UNESCO World Heritage. The altitudes vary between 200-1400m. The bedrock is composed of crystalline rocks and the land use is mainly forest and agriculture, with scattered urban settlements. The aim was to investigate the dynamics and availability of sediment contaminants in mountainous rural rivers, in a temperate climate. Active fluvial sediments (<63μm fraction) were studied with the aim of characterising the spatial and temporal distribution of the contents of Cd, Co, Cr, Ni, Cu, Zn, Pb, Fe and Mn, in the catchment. To assess possible different origins of metals (natural vs. anthropogenic), and potential availability, a sequential chemical approach was used (modified BCR procedure); the element concentrations were obtained by ICP-AES. The results suggest that Cr and Ni are the main metals from lithological source, with relatively higher contents in the residual fraction, and the lowest in the most mobile fractions. Copper, Zn and, in particular, Pb show higher concentrations in the most labile fractions, suggesting an important contribution of anthropogenic activities to the total contents in the sediments. The spatial distribution pattern of metal contents indicates higher contents of metals in the most mobile fractions occurring along the main courses of the major tributaries (in particular in the flatter reaches, where finer sediment preferentially accumulates). In

  20. A speleothem record of climate variability over the last millennium in the northern Wasatch Mountains, southeast Idaho

    NASA Astrophysics Data System (ADS)

    Lundeen, Z.; Brunelle, A.; Burns, S. J.; Asmerom, Y.; Polyak, V.

    2009-12-01

    A new speleothem isotope record from Minnetonka Cave, southeast Idaho, offers continuous decadal-resolution climate history over the last 800 years. The cave is located in the Bear River Range, the northernmost extension of the Wasatch Mountains, at an elevation of approximately 2400 meters. The Bear River Range is a primary hydrologic recharge area for the Bear River, the largest contributor to the Great Salt Lake. Correlation of the Minnetonka Cave isotope record with historic Great Salt Lake hydrograph data and regional historic temperature data indicate that the speleothem record quite accurately records changes in environmental conditions, at least over the instrumental period of record. The location of Minnetonka Cave is well situated to evaluate climate changes occurring at the boundary between northwest Pacific-dominated and the more arid southwest monsoon-dominated regions of North America. In addition, plans for diverting and impounding significant portions of Bear River water are currently being implemented by the State of Utah. Therefore, the data to be presented are also being used in an applied sense to evaluate the sustainability of those water resource developments in the context of observed climate variability over the last millennium.

  1. Contributions of natural and anthropogenic radiative forcing to mass loss of Northern Hemisphere mountain glaciers and quantifying their uncertainties.

    PubMed

    Hirabayashi, Yukiko; Nakano, Kazunari; Zhang, Yong; Watanabe, Satoshi; Tanoue, Masahiro; Kanae, Shinjiro

    2016-01-01

    Observational evidence indicates that a number of glaciers have lost mass in the past. Given that glaciers are highly impacted by the surrounding climate, human-influenced global warming may be partly responsible for mass loss. However, previous research studies have been limited to analyzing the past several decades, and it remains unclear whether past glacier mass losses are within the range of natural internal climate variability. Here, we apply an optimal fingerprinting technique to observed and reconstructed mass losses as well as multi-model general circulation model (GCM) simulations of mountain glacier mass to detect and attribute past glacier mass changes. An 8,800-year control simulation of glaciers enabled us to evaluate detectability. The results indicate that human-induced increases in greenhouse gases have contributed to the decreased area-weighted average masses of 85 analyzed glaciers. The effect was larger than the mass increase caused by natural forcing, although the contributions of natural and anthropogenic forcing to decreases in mass varied at the local scale. We also showed that the detection of anthropogenic or natural influences could not be fully attributed when natural internal climate variability was taken into account. PMID:27435236

  2. Distribution and origin of carbonaceous aerosol over a rural high-mountain lake area, Northern China and its transport significance

    NASA Astrophysics Data System (ADS)

    Han, Y. M.; Han, Z. W.; Cao, J. J.; Chow, J. C.; Watson, J. G.; An, Z. S.; Liu, S. X.; Zhang, R. J.

    PM 2.5 and TSP samples were collected at Lake Daihai, a rural high-mountain area in China, in four seasons during 2005-2007. Organic carbon (OC), elemental carbon (EC), char-EC, and soot-EC were analyzed using the thermal/optical reflectance (TOR) method with different temperature plateaus and oxidation atmospheres. TC, OC, EC, and char-EC concentrations of TSP and PM 2.5 showed seasonal variations with the highest concentrations in winter and the lowest in summer, while soot-EC reveals a little different variation, with the highest concentration in spring, indicating different source contributions from other parameters. OC/EC correlations were weaker at Daihai than those from urban areas. Although little differences existed in TSP and PM 2.5, average OC/EC ratios varied seasonally and ranged from ˜9.0 in winter to ˜5.0 in spring. Char-/soot-EC ratios showed similar pattern, with the highest average ratios (>3.0) in winter, consistent with the contributions from residential biomass burning and coal combustion. Back trajectories related the highest carbon concentrations with the southeasterly air masses and the lowest carbon levels with northward flows.

  3. Contributions of natural and anthropogenic radiative forcing to mass loss of Northern Hemisphere mountain glaciers and quantifying their uncertainties

    NASA Astrophysics Data System (ADS)

    Hirabayashi, Yukiko; Nakano, Kazunari; Zhang, Yong; Watanabe, Satoshi; Tanoue, Masahiro; Kanae, Shinjiro

    2016-07-01

    Observational evidence indicates that a number of glaciers have lost mass in the past. Given that glaciers are highly impacted by the surrounding climate, human-influenced global warming may be partly responsible for mass loss. However, previous research studies have been limited to analyzing the past several decades, and it remains unclear whether past glacier mass losses are within the range of natural internal climate variability. Here, we apply an optimal fingerprinting technique to observed and reconstructed mass losses as well as multi-model general circulation model (GCM) simulations of mountain glacier mass to detect and attribute past glacier mass changes. An 8,800-year control simulation of glaciers enabled us to evaluate detectability. The results indicate that human-induced increases in greenhouse gases have contributed to the decreased area-weighted average masses of 85 analyzed glaciers. The effect was larger than the mass increase caused by natural forcing, although the contributions of natural and anthropogenic forcing to decreases in mass varied at the local scale. We also showed that the detection of anthropogenic or natural influences could not be fully attributed when natural internal climate variability was taken into account.

  4. Contributions of natural and anthropogenic radiative forcing to mass loss of Northern Hemisphere mountain glaciers and quantifying their uncertainties

    PubMed Central

    Hirabayashi, Yukiko; Nakano, Kazunari; Zhang, Yong; Watanabe, Satoshi; Tanoue, Masahiro; Kanae, Shinjiro

    2016-01-01

    Observational evidence indicates that a number of glaciers have lost mass in the past. Given that glaciers are highly impacted by the surrounding climate, human-influenced global warming may be partly responsible for mass loss. However, previous research studies have been limited to analyzing the past several decades, and it remains unclear whether past glacier mass losses are within the range of natural internal climate variability. Here, we apply an optimal fingerprinting technique to observed and reconstructed mass losses as well as multi-model general circulation model (GCM) simulations of mountain glacier mass to detect and attribute past glacier mass changes. An 8,800-year control simulation of glaciers enabled us to evaluate detectability. The results indicate that human-induced increases in greenhouse gases have contributed to the decreased area-weighted average masses of 85 analyzed glaciers. The effect was larger than the mass increase caused by natural forcing, although the contributions of natural and anthropogenic forcing to decreases in mass varied at the local scale. We also showed that the detection of anthropogenic or natural influences could not be fully attributed when natural internal climate variability was taken into account. PMID:27435236

  5. Driving Forces of Dynamic Changes in Soil Erosion in the Dahei Mountain Ecological Restoration Area of Northern China Based on GIS and RS

    PubMed Central

    Li, Xiao; Niu, Xiang; Wang, Bing; Gao, Peng; Liu, Yu

    2016-01-01

    Dynamic change in soil erosion is an important focus of regional ecological restoration research. Here, the dynamic changes of soil erosion and its driving forces in the Dahei Mountain ecological restoration area of northern China were analyzed by LANDSAT TM remote sensing captured via geographic information system (GIS) technologies during three typical periods in 2004, 2008 and 2013. The results showed the following: (1) a decrease in intensive erosion and moderate erosion areas, as well as an increase in light erosion areas, was observed during two periods: one from 2004 to 2008 and the other from 2008 to 2013. (2) Between 2004 and 2008, the variation in the range of slight erosion was the largest (24.28%), followed by light erosion and intensive erosion; between 2008 and 2013, the variation in the range of intensive erosion area was the largest (9.89%), followed by slight erosion and moderate erosion. (3) Socioeconomic impact, accompanied by natural environmental factors, was the main driving force underlying the change in soil erosion within the ecological restoration area. In particular, the socioeconomic factors of per capita forest area and land reclamation rate, as well as the natural environmental factor of terrain slope, significantly influenced soil erosion changes within the ecological restoration area. PMID:26981637

  6. A comparison of rates of hornblende etching in soils in glacial deposits of the northern Rocky Mountains: Influence of climate and characteristics of parent material

    SciTech Connect

    Horn, L.L. . Dept. of Geology); Hall, R.D. . Dept. of Geology)

    1993-04-01

    Etching rates of hornblende grains in the soil matrix of glacial deposits in the Northern Rocky Mountains are dependent primarily upon the influences on soil moisture of the climate and texture of the parent materials. Etching is measured as the deepest penetration of weathering along cleavages. Previous works have shown that hornblende etching is a logarithmic function of depth. Hornblende etching is also a logarithmic function of age of the parent material, with etching rates declining rapidly after initially high rates during the first 10 to 15 kyr after deposition. A comparison of etching rates was made among four chronosequences from the Wind River Range, Wyoming and the Tobacco Root Range, Montana, which have differences in mean annual precipitation (MAP) and texture of the till parent materials. Using rates calculated from both ranges for the first 12 kyr after deposition, etching is slowest (0.02 [mu]m/1,000 yrs) in coarse-textured granitic parent materials where the MAP is 25--40 cm. In contrast, etching is faster by an order of magnitude (0.21 [mu]m/1,000 yrs) where MAP is 110--150 cm and the parent material is finer textured due to about 15% sedimentary rock material mixed with a granitic component. Within individual chronosequences, deposits at higher elevations have accelerated etching rates due to higher orographic precipitation or the influence of late-lying snow. These factors result in higher soil moisture content.

  7. Analysis of feature intervisibility and cumulative visibility using GIS, Bayesian and spatial statistics: a study from the Mandara Mountains, northern Cameroon.

    PubMed

    Wright, David K; MacEachern, Scott; Lee, Jaeyong

    2014-01-01

    The locations of diy-geδ-bay (DGB) sites in the Mandara Mountains, northern Cameroon are hypothesized to occur as a function of their ability to see and be seen from points on the surrounding landscape. A series of geostatistical, two-way and Bayesian logistic regression analyses were performed to test two hypotheses related to the intervisibility of the sites to one another and their visual prominence on the landscape. We determine that the intervisibility of the sites to one another is highly statistically significant when compared to 10 stratified-random permutations of DGB sites. Bayesian logistic regression additionally demonstrates that the visibility of the sites to points on the surrounding landscape is statistically significant. The location of sites appears to have also been selected on the basis of lower slope than random permutations of sites. Using statistical measures, many of which are not commonly employed in archaeological research, to evaluate aspects of visibility on the landscape, we conclude that the placement of DGB sites improved their conspicuousness for enhanced ritual, social cooperation and/or competition purposes. PMID:25383883

  8. Late Quaternary climatic and tectonic mechanisms driving river terrace development in an area of mountain uplift: A case study in the Langshan area, Inner Mongolia, northern China

    NASA Astrophysics Data System (ADS)

    Jia, Liyun; Zhang, Xujiao; He, Zexin; He, Xiangli; Wu, Fadong; Zhou, Yiqun; Fu, Lianzhen; Zhao, Junxiang

    2015-04-01

    The Langshan Range is located in the western Yin Mountain orogenic belts and the western Hetao fault-depression zone in Inner Mongolia, northern China. This area is on the northwestern margin of the East Asian monsoon region. The fluvial terraces in the transverse drainage of the Langshan Range represent a primary geomorphic response to local tectonic uplift and climatic changes. The terrace evolution was reconstructed using a combination of optically stimulated luminescence (OSL) dating and terrace tread measurements. The terraces, designated T4 through T1, were abandoned at about 58.00, 46.25, 32.19, and 15.79 ka BP, respectively. Their aggradation occurred primarily during cold periods of the last glacial stage, and incision occurred primarily during shifts from cold to warm climate stages. Geomorphic analysis showed the terrace heights were controlled by the tectonic uplift in the area. Differences in river incision rates and terrace geomorphic features indicate that the uplift of the Langshan Range included a component of tilting north to south during the period of 58.00-41.28 ka BP, whereas the uplift of the Langshan area tended to be equal on a regional scale after 32.19 ka BP.

  9. Driving Forces of Dynamic Changes in Soil Erosion in the Dahei Mountain Ecological Restoration Area of Northern China Based on GIS and RS.

    PubMed

    Li, Xiao; Niu, Xiang; Wang, Bing; Gao, Peng; Liu, Yu

    2016-01-01

    Dynamic change in soil erosion is an important focus of regional ecological restoration research. Here, the dynamic changes of soil erosion and its driving forces in the Dahei Mountain ecological restoration area of northern China were analyzed by LANDSAT TM remote sensing captured via geographic information system (GIS) technologies during three typical periods in 2004, 2008 and 2013. The results showed the following: (1) a decrease in intensive erosion and moderate erosion areas, as well as an increase in light erosion areas, was observed during two periods: one from 2004 to 2008 and the other from 2008 to 2013. (2) Between 2004 and 2008, the variation in the range of slight erosion was the largest (24.28%), followed by light erosion and intensive erosion; between 2008 and 2013, the variation in the range of intensive erosion area was the largest (9.89%), followed by slight erosion and moderate erosion. (3) Socioeconomic impact, accompanied by natural environmental factors, was the main driving force underlying the change in soil erosion within the ecological restoration area. In particular, the socioeconomic factors of per capita forest area and land reclamation rate, as well as the natural environmental factor of terrain slope, significantly influenced soil erosion changes within the ecological restoration area. PMID:26981637

  10. Analysis of Feature Intervisibility and Cumulative Visibility Using GIS, Bayesian and Spatial Statistics: A Study from the Mandara Mountains, Northern Cameroon

    PubMed Central

    Wright, David K.; MacEachern, Scott; Lee, Jaeyong

    2014-01-01

    The locations of diy-geδ-bay (DGB) sites in the Mandara Mountains, northern Cameroon are hypothesized to occur as a function of their ability to see and be seen from points on the surrounding landscape. A series of geostatistical, two-way and Bayesian logistic regression analyses were performed to test two hypotheses related to the intervisibility of the sites to one another and their visual prominence on the landscape. We determine that the intervisibility of the sites to one another is highly statistically significant when compared to 10 stratified-random permutations of DGB sites. Bayesian logistic regression additionally demonstrates that the visibility of the sites to points on the surrounding landscape is statistically significant. The location of sites appears to have also been selected on the basis of lower slope than random permutations of sites. Using statistical measures, many of which are not commonly employed in archaeological research, to evaluate aspects of visibility on the landscape, we conclude that the placement of DGB sites improved their conspicuousness for enhanced ritual, social cooperation and/or competition purposes. PMID:25383883

  11. Integrating physical and chemical characteristics of lakes into the glacially influenced landscape of the Northern Cascade Mountains, Washington State, USA

    USGS Publications Warehouse

    Larson, Gary L.; Lomnicky, G.A.; Liss, W.J.; Deimling, E.

    1999-01-01

    A basic knowledge of the physical and chemical characteristics of lakes is needed by management to make informed decisions to protect water resources. In this study we investigated some of the physical and chemical characteristics of 58 lakes in alpine, subalpine, and forest vegetation zones in a natural area (North Cascades National Park Service Complex) between 1989 and 1993. The objectives of the study were to: (1) document the time of ice-out relative to lake elevation; (2) determine how a sharp climate gradient west and east of the hydrologic divide affected the time of ice-out for subalpine lakes; and (3) assess how lake water quality was associated with lake elevation, lake depth, and basin geology. As expected, lake ice-out times occurred earlier with decreasing elevation. East-slope subalpine lakes iced-out earlier than did west-slope subalpine lakes because the east slope of the study area was drier and warmer than the west slope. On average, the lakes were relatively cold, neutral in pH, and low in dissolved substances and concentrations of nitrogen and phosphorus. Although some shallow lakes (depth ,10 m) exhibited the highest alkalinities, conductivities, and concentrations of phosphorus and nitrogen, most shallow lakes exhibited low values for these variables that were comparable to values observed in deep lakes. Geology did not play a major role in segregating the lakes based on water quality. Overall, lake temperature, pH, alkalinity, conductivity, and concentrations of total phosphorus and total Kjeldahl N increased with decreasing elevation. These changes in water quality with decreasing elevation in this temperate mountainous region corresponded with warmer air temperatures and increased vegetation biomass, soil depth and maturity, and dissolved substances and nutrients.

  12. High-alumina basalts from the Bogda Mountains suggest an arc setting for Chinese Northern Tianshan during the Late Carboniferous

    NASA Astrophysics Data System (ADS)

    Xie, Wei; Xu, Yi-Gang; Chen, Yi-Bing; Luo, Zhen-Yu; Hong, Lu-Bing; Ma, Liang; Liu, Hai-Quan

    2016-07-01

    Considerable debate persists as to the tectonic setting of the Tianshan Orogen during the Late Paleozoic, with active subduction system and intraplate large igneous provinces as two dominant schools. With aims of providing constraints on this issue, geochronological and geochemical analyses have been carried out on the Late Carboniferous high-Al basaltic lava (HAB) from the Bogda Mountains. These lavas, in conformable contact with the felsic rocks, belong to the Upper Carboniferous Liushugou Group. Zircon SHRIMP U-Pb dating of two felsic ignimbrites further suggest that they were mainly erupted during 315-319 Ma. The Bogda basaltic lava is classified as HAB given their high Al contents > 16% and their chemical resemblance to those from modern arcs such as Aleutian and Kamchatka. They are characterized by strong enrichment in large ion lithophile elements (LILE), strong negative Nb-Ta and Ti anomalies, and distinct positive Pb anomalies. Hence, they are significantly different from the mantle plume-related basalts, as exemplified by those from Siberian, Emeishan, and Tarim large igneous provinces. Instead, their MORB-like Nd-Hf-Pb isotopes and arc-like trace elements indicate that the Bogda HABs may have been generated from a mantle wedge metasomatized by sediment-derived melts. The sector and oscillatory zoning in clinopyroxene phenocrysts in the Bogda HABs is attributable to rapid dynamic crystallization during magma ascent. High Al content is due to delayed plagioclase nucleation likely by the high crystallization pressure rather than water content. Collectively, our data lend support to an island arc environment during the Late Paleozoic, probably related to southward subduction of the Paleo-Tianshan Ocean.

  13. A cholera outbreak in Alborz Province, Iran: a matched case-control study

    PubMed Central

    2016-01-01

    OBJECTIVES: A total of 229 confirmed cholera cases were reported in Alborz Province during an outbreak that lasted from June 2011 to August 2011. This study aimed to identify potential sources of transmission in order to determine suitable interventions in similar outbreaks. In other words, the lessons learned from this retrospective study can be utilized to manage future similar outbreaks. METHODS: An age-matched and sex-matched case-control study was conducted during the outbreak. For each case, two control subjects were selected from the neighborhood. A case of cholera was defined as a bacteriologically confirmed case with signs and symptoms of cholera. This study was conducted from June 14, 2011 through August 23, 2011. The data were analyzed by calculating odds ratios (ORs) using the logistic regression method. RESULTS: In this outbreak, 229 confirmed cholera cases were diagnosed. The following risk factors were found to be associated with cholera: consumption of unrefrigerated leftover food (OR, 3.05; 95% confidence interval [CI], 1.72 to 5.41), consumption of vegetables and fruits in the previous three days (OR, 2.75; 95% CI, 1.95 to 3.89), and a history of traveling in the previous five days (OR, 5.31; 95% CI, 2.21 to 9.72). CONCLUSIONS: Consumption of vegetables and fruits has remained an unresolved risk factor in cholera outbreaks in Iran in recent years. In order to reduce the risk of cholera, sanitary standards for fruits and vegetables should be observed at all points from production to consumption, the population should be educated regarding hygienic food storage during outbreaks, and sanitary standards should be maintained when traveling during cholera outbreaks. PMID:27188308

  14. Responses of mammal dispersers to fruit availability: Rowan ( Sorbus aucuparia) and carnivores in mountain habitats of northern Spain

    NASA Astrophysics Data System (ADS)

    Guitián, José; Munilla, Ignacio

    2010-03-01

    Despite the well known fact that carnivore mammals are important fruit consumers and legitimate seed dispersers in temperate habitats, little is known about their quantitative responses to fruit availability. Here we show the results of two studies conducted at two different temporal and spatial scales, that were intended to assess the response of pine martens ( Martes martes) and red foxes ( Vulpes vulpes) to variations in the supply of rowan ( Sorbus aucuparia) fruits in the Cantabrian Range (northern Iberia). First, we studied the association between fruit availability and the importance of rowan fruit in the diet of carnivores during a period of 11 consecutive years. This was accomplished by comparing fruit-crop size in 54 trees and the analysis of faecal contents in a sample of 863 faeces. Secondly, we assessed the consumption of fruits by these two species underneath the canopy of 20 rowan trees along 10 consecutive days. In the first study, the diet of martens and foxes consistently tracked interannual variations in rowan fruit availability, despite large fluctuations in fruit yield that included three mast years of heavy rowanberry crops and three non-fruiting years. For both carnivores total crop size was correlated with the frequency of occurrence and the proportion of rowan by volume in faeces. The second study suggested that carnivores feeding on fallen fruit tended to visit the trees that exhibited a higher density of fruits under the canopy. Thus, carnivores apparently choose to feed on high-density patches of fruit, which in turn were located underneath the canopy of the trees that produced the larger crops. Our results stress the need to pay proper attention to the role of carnivores as seed dispersers, in order to disentangle the evolutionary and ecological outcomes of plant-animal interactions in mixed-dispersed plants.

  15. Magnetic properties derived from a loess section at the northern piedmont of Tianshan Mountains, Xinjiang, China, and their paleoenvironmental significance

    NASA Astrophysics Data System (ADS)

    Li, Guanhua; Xia, Dunsheng; Jia, Jia; Zhao, Shuang; Gao, Fuyuan; Wang, Youjun; Lu, Hao; Chen, Fahu

    2015-11-01

    Loess deposits in the arid Central Asia contain valuable information on the evolution of local aridification and dust sources in the Northern Hemisphere. Xinjiang is located in the eastern part of Central Asia and previous researches have revealed the complex enhancement of magnetic susceptibility in loess-paleosol sequences. However, systematic magnetic archives of loess deposit in this arid Asian interior are still far from adequate. In this study, magnetic parameters combined with nonmagnetic properties (granulometry and chromaticity) were analysed on a loess section in Shawan (SW), northwestern China. The section shares a similar magnetic composition with those in the Chinese Loess Plateau (CLP) as well as other sites in Xinjiang. Ferrimagnetic components (magnetite and maghemite) dominate the magnetic signal while the contribution of antiferromagnetic phases (like hematite and goethite) and paramagnetic portions are relatively low. There is no specific correlation between magnetic concentration and pedogenic intensity in the SW section. In general, magnetic enhancement was largely influenced by the paleowind intensity. However, a positive correlation between magnetic susceptibility and pedogenesis is observed in the upper part (0-3.5 m depths), which is characterized by a moderate wind intensity. Moreover, pedogenesis might be responsible for the enhancement of fine magnetic particles in paleosols. Magnetic properties are controlled by coarse magnetic particles in the pseudo-single domain state, but a coarse stable single domain phase was found in certain paleosol samples. The input of detrital fractions from a nearby dust source probably controlled the magnetic properties while a superparamagnetic fraction, which has been deemed as a product of pedogenesis in the CLP, is limited in the SW section. Caution is needed to employ magnetic susceptibility directly for paleoclimatic assessment because of its uncertainty in the Xinjiang loess. However, the

  16. Catchment rehabilitation and hydro-geomorphic characteristics of mountain streams in the western Rift Valley escarpment of Northern Ethiopia

    NASA Astrophysics Data System (ADS)

    Ghebreyohannes Asfaha, Tesfaalem; Frankl, Amaury; Haile, Mitiku; Nyssen, Jan

    2013-04-01

    The catchments in the western Rift Valley escarpment of Northern Ethiopia are highly responsive in terms of hydro-geomorphic changes. With rapid deforestation in the first half of the 20th century, dense gully and scar networks developed, exporting huge amounts of runoff and sediment down to the fertile and densely populated Raya Valley. Consequently, threatening the environment and the livelihoods of the people both in the upstream and downstream areas. To reverse this problem, catchment-scale rehabilitation activities were initiated in the mid-1980s. In this study, we examine the hydro-geomorphic response of streams after catchment rehabilitation. Scar density was digitized from Google Earth imagery (2005) in 20 adjacent catchments and was explained in terms of its corresponding Normalized Difference Vegetation Index (NDVI) and slope gradient. This was accompanied by analysis of incidental repeat photographs and field observations. As evidenced by the series of repeat photographs, the vegetation cover of the catchments decreased up to 1975 and rapid reforestation occurred thereafter. A multiple regression analysis (R2=0.53, P<0.01) showed that scar density is negatively correlated with NDVI and positively with average gradient of very steep slopes (>60%). Moreover, due to reduction in discharge and sediment flow from the rehabilitated catchments, stream adjustments were observed in the field: previously braided stream channels have changed to single-thread streams, many lateral bars are stabilized and covered by vegetation, stream channels are incising due to clear water effect and the size of boulder deposits decreases. Therefore, the study shows that, land degradation activities in the upper catchments resulted in changes in hydro-geomorphic characteristics of the streams and reduction in runoff and sediment transport to the Raya Valley. Key words: scar density; NDVI; stream incision; soil and water conservation; stream adjustment; land use change.

  17. Northern Rocky Mountain Wildfires and Debris Flows: Millennial-Scale Interactions among Climate, Fire, Vegetation, and Geomorphic Response

    NASA Astrophysics Data System (ADS)

    Pierce, J. L.; Riley, K. E.; Weppner, K.

    2012-12-01

    As summer droughts and rising temperatures in the Western U.S. continue to fuel large wildfires, understanding the role of fire in mountain ecosystems becomes increasingly relevant. Past relationships among fire, climate, and vegetation change may help place recent fires within a historic context. In addition, post-fire floods and debris flows contribute large amounts of sediment to rivers and streams. Quantifying fire-related sediment inputs is important for disciplines ranging from stream ecology to landscape evolution. We examine evidence of fires and related hillslope erosion through 14C dating of alluvial charcoal fragments preserved in Holocene fire-related deposits in alluvial fans and stream sediments throughout a range of ecosystems in Idaho, USA. In addition, we measure sediment yields from recent fire-related debris flows and extrapolate the contribution of fire-related sediment inputs to streams over millennial timescales. Over Holocene timescales, independent records of forest-fires and fire-related erosion from ecosystems ranging from sagebrush steppe, pinion-juniper, ponderosa pine, lodgepole pine and mixed conifer forests indicate that sedimentation rates and processes on alluvial fans vary temporally with Holocene climate, and spatially with vegetation type. Despite variations in ecosystem type and associated fire regimes, many sites show similar broad-scale patterns. During the Pleistocene-Holocene transition large fires burned across many ecosystems. The mid-Holocene (~4-8 ka) is characterized by few fire-related deposits; however, this relatively fire-free interval is punctuated by fire peaks and associated sheetflooding ~7-6 ka. Since regional paleoclimatic reconstructions indicate the mid-Holocene was generally warm and dry the lack of fire is somewhat counterintuitive; however, decreased fuel loads, combined with perhaps a more stable climate may reduce fire and storm intensity and frequency. The late Holocene (last ~3 ka) cooler, wetter and

  18. The relation of harvesting intensity to changes in soil, soil water, and stream chemistry in a northern hardwood forest, Catskill Mountains, USA

    USGS Publications Warehouse

    Siemion, Jason; Burns, Douglas A.; Murdoch, Peter S.; Germain, Rene H.

    2011-01-01

    Previous studies have shown that clearcutting of northern hardwood forests mobilizes base cations, inorganic monomeric aluminum (Alim), and nitrate (NO3--N) from soils to surface waters, but the effects of partial harvests on NO3--N have been less frequently studied. In this study we describe the effects of a series of partial harvests of varying proportions of basal area removal (22%, 28% and 68%) on Alim, calcium (Ca2+), and NO3--N concentrations in soil extracts, soil water, and surface water in the Catskill Mountains of New York, USA. Increases in NO3--N concentrations relative to pre-harvest values were observed within a few months after harvest in soils, soil water, and stream water for all three harvests. Increases in Alim and Ca2+ concentrations were also evident in soil water and stream water over the same time period for all three harvests. The increases in Alim, Ca2+, and NO3--N concentrations in the 68% harvest were statistically significant as measured by comparing the 18-month pre-harvest period with the 18-month post-harvest period, with fewer significant responses in the two harvests of lowest intensity. All three solutes returned to pre-harvest concentrations in soil water and stream water in the two lowest intensity harvests in 2–3 years compared to a full 3 years in the 68% harvest. When the results of this study were combined with those of a previous nearby clearcut and 40% harvest, the post-harvest increases in NO3--N concentrations in stream water and soil water suggest a harvesting level above which the relation between concentration and harvest intensity changes; there was a greater change in concentration per unit change in harvest intensity when basal area removal was greater than 40%. These results indicate that the deleterious effects on aquatic ecosystems previously demonstrated for intensive harvests in northern hardwood forests of northeastern North America that receive high levels of atmospheric N deposition can be greatly

  19. Determining the sensitivity of the high mountain region in Northern Romania to climate and land use changes through multi-proxy analysis

    NASA Astrophysics Data System (ADS)

    Feurdean, Angelica; Geanta, Anca; Tantau, Ioan; Auer, Andreea; Hutchinson, Simon

    2013-04-01

    Climate and land use changes can have a great impact on high altitude environments due to their species' narrow tolerance capabilities, habitat fragmentation and habitat restriction. Since trees at the timberline and the treeline ecotone grow at their temperature and soil tolerance limit, even small alterations in these parameters can result in marked changes in the position of the treeline ecotone, diversity, and species composition. Current and future climate warming is anticipated to shift the tree and timberlines upwards, whereas land use changes can drive this movement in the opposite direction. Therefore the long-term responses of vegetation to past climate variations and land use changes are of particular relevance for the prediction of future vegetation change in high mountain areas. Here, we use a multi-proxy analysis (pollen, spores, micro and macrocharcoal, mineral magnetic properties and AMS 14C dating) of a 1m lacustrine sequence covering the last 5000 years located in the subalpine zone (1910 m a.s.l.) in the Rodna Mountains (Northern Romanian Carpathians) to determine the sensitivity of high mountain habitats (i.e., movements of the timberline and treeline ecotones, and changes in vegetation composition diversity) in response to climate, fires and land use. The pollen and stomata records reveal regional forests dominated by Pinus sylvestris between ca. 5000 and 4250 cal yrs BP, which were replaced by Picea abies, Abies alba and Fagus sylvatica from about 4200 cal yrs BP onwards. The proximity of the lake was treeless, dominated by sub-alpine shrubs (Alnus viridis), alpine herbaceous communities (Poaceae, Cyperaceae, Apiaceae, Asteraceae Tubuliflorae, A. Liguliflorae, Thalictrum) and ruderal species (Artemisia, Rumex, Chenopodiaceae) through almost the whole record. However, Pinus stomata found between 5000 and 4000 cal yr BP probably indicate a higher position of the treeline and the local occurrence of Pinus before 4000 cal yr BP. Our results show

  20. Use of airborne imaging spectrometer data to map minerals associated with hydrothermally altered rocks in the northern grapevine mountains, Nevada, and California

    USGS Publications Warehouse

    Kruse, F.A.

    1988-01-01

    Three flightlines of Airborne Imaging Spectrometer (AIS) data, acquired over the northern Grapevine Mountains, Nevada, and California, were used to map minerals associated with hydrothermally altered rocks. The data were processed to remove vertical striping, normalized using an equal area normalization, and reduced to reflectance relative to an average spectrum derived from the data. An algorithm was developed to automatically calculate the absorption band parameters band position, band depth, and band width for the strongest absorption feature in each pixel. These parameters were mapped into an intensity, hue, saturation (IHS) color system to produce a single color image that summarized the absorption band information, This image was used to map areas of potential alteration based upon the predicted relationships between the color image and mineral absorption band. Individual AIS spectra for these areas were then examined to identify specific minerals. Two types of alteration were mapped with the AIS data. Areas of quartz-sericite-pyrite alteration were identified based upon a strong absorption feature near 2.21 ??m, a weak shoulder near 2.25 ??m, and a weak absorption band near 2.35 ??m caused by sericite (fine-grained muscovite). Areas of argillic alteration were defined based on the presence of montmorillonite, identified by a weak to moderate absorption feature near 2.21 ??m and the absence of the 2.35 ??m band. Montmorillonite could not be identified in mineral mixtures. Calcite and dolomite were identified based on sharp absorption features near 2.34 and 2.32 ??m, respectively. Areas of alteration identified using the AIS data corresponded well with areas mapped using field mapping, field reflectance spectra, and laboratory spectral measurements. ?? 1988.

  1. Transport of airborne Picea schrenkiana pollen on the northern slope of Tianshan Mountains (Xinjiang, China) and its implication for paleoenvironmental reconstruction.

    PubMed

    Pan, Yanfang; Yan, Shun; Behling, Hermann; Mu, Guijin

    2013-06-01

    The understanding of airborne pollen transportation is crucial for the reconstruction of the paleoenvironment. Under favorable conditions, a considerable amount of long-distance-transported pollen can be deposited far from its place of origin. In extreme arid regions, in most cases, such situations occur and increase the difficulty to interpret fossil pollen records. In this study, three sets of Cour airborne pollen trap were installed on the northern slope of Tianshan Mountains to collect airborne Picea schrenkiana (spruce) pollen grains from July 2001 to July 2006. The results indicate that Picea pollen disperses extensively and transports widely in the lower atmosphere far away from spruce forest. The airborne Picea pollen dispersal period is mainly concentrated between mid-May and July. In desert area, weekly Picea pollen began to increase and peaked suddenly in concentration. Also, annual pollen indices do not decline even when the distance increased was probably related to the strong wind may pick up the deposited pollen grains from the topsoil into the air stream, leading to an increase of pollen concentration in the air that is irrelevant to the normal and natural course of pollen transport and deposition. This, in turn, may lead to erroneous interpretations of the pollen data in the arid region. This study provided insight into the shift in the Picea pollen season regarding climate change in arid areas. It is recorded that the pollen pollination period starts earlier and the duration became longer. The results also showed that the temperature of May and June was positively correlated with the Picea pollen production. Furthermore, the transport of airborne Picea pollen data is useful for interpreting fossil pollen records from extreme arid regions. PMID:23576840

  2. Effects of Pre-Fire Fuels Treatments on Post-Fire Burn Severity on the 2007 Fires in the Northern Rocky Mountains, USA

    NASA Astrophysics Data System (ADS)

    Hudak, A. T.; Morgan, P.; Robichaud, P. R.; Lewis, S. A.; Evans, J. S.

    2007-12-01

    Climate change may be contributing to regional warming and drying trends that are increasing the size and severity of wildfires. Regardless if climate is a factor, the escalating costs of fire suppression and post-fire rehabilitation on the many large fires of recent decades have driven a national effort to reduce hazardous fuels across large areas, particularly those in the wildland-urban interface (WUI). Nationally, concern is especially focused on the numerous large wildfires currently burning in the Northern Rocky Mountains with a need for rapid science-based assessment of burn severity, even as fires and fire suppression efforts continue. Our objective is to assess if and how well various fuels reduction treatments applied pre-fire mitigated burn severity measured in the field immediately post-fire. We will obtain data from the incident command teams, including fire weather, daily fire progression maps, and where strategic and tactical fire suppression measures were applied. Location and type of fuels treatment as well as data on local vegetation type, structure, and fuels will be obtained from local management agencies and national databases. We will pair our sampled field plots in treated and burned areas with those not treated and burned in similar stand and topographic conditions across three or more large forest fires. Our analysis is both quantitative and qualitative, and linked with efforts to assess fuel treatment effects on fire behavior and ease of fire suppression. We report specifically on whether various fuels treatments are mitigating fire effects on soil (e.g., char, percent exposed, infiltration rate, water repellency) and vegetation (e.g., scorch, tree mortality, understory abundance, recovery). We discuss which fuels treatments work and which do not work, and the extent to which fire weather and other factors beyond the control of fire managers may determine whether or not fuels treatments are effectively mitigating severe fire effects.

  3. [Vertical variability of Pinus sylvestris var. mongolica tree ring delta13C and its relationship with tree ring width in northern Daxing' an Mountains of Northeast China].

    PubMed

    Shang, Zhi-Yuan; Wang, Jian; Zhang, Wen; Li, Yan-Yan; Cui, Ming-Xing; Chen, Zhen-Ju; Zhao, Xing-Yun

    2013-01-01

    A measurement was made on the vertical direction tree ring stable carbon isotope ratio (delta13C) and tree ring width of Pinus sylvestris var. mongolica in northern Daxing' an Mountains of Northeast China, with the relationship between the vertical direction variations of the tree ring delta13C and tree ring width analyzed. In the whole ring of xylem, earlywood (EW) and bark endodermis, the delta13C all exhibited an increasing trend from the top to the base at first, with the maximum at the bottom of tree crown, and then, decreased rapidly to the minimum downward. The EW and late-wood (LW) had an increasing ratio of average tree ring width from the base to the top. The average annual sequence of the delta13C in vertical direction had an obvious reverse correspondence with the average annual sequence of tree ring width, and had a trend comparatively in line with the average annual sequence of the tree ring width ratio of EW to LW above tree crown. The variance analysis showed that there existed significant differences in the sequences of tree ring delta13C and ring width in vertical direction, and the magnitude of vertical delta13C variability was basically the same as that of the inter-annual delta13C variability. The year-to-year variation trend of the vertical delta13C sequence was approximately identical. For each sample, the delta13C sequence at the same heights was negatively correlated with the ring width sequence, but the statistical significance differed with tree height. PMID:23717983

  4. Compilation of data on strippable Fort Union coals in the northern Rocky Mountains and Great Plains region: A CD-ROM presentation

    SciTech Connect

    Flores, R.M.; Bader, L.R.; Cavaroc, V.V.

    1998-04-01

    The Fort Union Formation and equivalent formations of Paleocene age in the northern Rocky Mountains and Great Plains region contain 14 strippable coals that yielded more than 30 percent of the 1.03 billion short tons produced in the United States in 1996. These thick, low contaminant, compliant coals, which are utilized by electric power plants in 28 States, are being assessed by the US Geological Survey. The minable coals occur in the Powder River Basin in Wyoming and Montana, Hanna, Carbon and Greater Green River Basins in Wyoming, and Williston Basin in North Dakota. Production during the past 25 years of thick, high quality Fort Union and equivalent coal beds and zones in the region increased from 40 to more than 340 million short tons. The Powder River Basin is projected to produce 416 million short tons of coal in 2015. Major production in the Powder River Basin is from the Wyodak-Anderson, Anderson-Dietz, and Rosebud coal deposits. Producing Fort Union coals in the Williston Basin include the Beulah-Zap, Hagel, and Harmon coal deposits. Producing Fort Union coals in the Greater Green River Basin are in five beds of the Deadman coal zone. Coal production in the Hanna Basin is from eight beds in the Ferris and Hanna Formations. Coals in the Powder River Basin and Williston Basin contain much less sulfur and ash than coals produced in other regions in the conterminous US. When sulfur values are compared as pounds of SO{sub 2} per million Btu (as received basis), Powder River Basin and Williston Basin coals have the lowest amounts of any coals in the conterminous US.

  5. Role of New Nature Reserve in Assisting Endangered Species Conservation - Case Study of Giant Pandas in the Northern Qionglai Mountains, China.

    PubMed

    Guan, Tian-Pei; Owens, Jacob R; Gong, Ming-Hao; Liu, Gang; Ouyang, Zhi-Yun; Song, Yan-Ling

    2016-01-01

    The creation of nature reserves is the most direct way to save endangered species populations and their habitat. Development of the giant panda (Ailuropoda melanoleuca) nature reserve network in China was initiated in the 1960s, though the effort to create new reserves boomed considerably after the year 2000. Given this rapid development of protected areas in panda habitats, and the potential conflicting interests between conservation administrations and local economic development, it is essential to assess the role of new nature reserves in the overall giant panda conservation effort and reserve network. We utilized data from national giant panda surveys conducted in 2000 and 2012 to compare the size, spatial use, and distribution of panda populations, as well as the habitat suitability and connectivity in the Northern Qionglai Mountains between the two survey years. Our results show that although the total giant panda population in the study area did not change remarkably, local changes did occur. Most notably, the population in Wolong Nature Reserve declined by 27.3% (N = 39) and the population in Caopo Nature Reserve increased by 71.4% (N = 29) over the 12-year study period. We also found habitat suitability and availability decreased in both Wolong (12.4%) and Caopo (7.4%), but that the relative density of giant pandas declined (19.2%) and increased (84.6%) at each site, respectively. The distance between centers of high IUA were more distant in 2012 (14.1±1.9km) than that in 2000 (6.1±0.9km; t = -7.4, df = 5, p = 0.001), showing a scattered spatial pattern. Habitat availability decreased by 42% within the corridor between the two reserves, however panda occurrences in the corridor increased 24.6%. Compared to the total number of encounters, the proportion of the corridor increased 45.76%. Our results show the importance and success of the newly established Caopo to the conservation of giant pandas, and how crucial it is to identify and repair reserve

  6. Role of New Nature Reserve in Assisting Endangered Species Conservation - Case Study of Giant Pandas in the Northern Qionglai Mountains, China

    PubMed Central

    Guan, Tian-Pei; Owens, Jacob R.; Gong, Ming-Hao; Liu, Gang; Ouyang, Zhi-Yun; Song, Yan-Ling

    2016-01-01

    The creation of nature reserves is the most direct way to save endangered species populations and their habitat. Development of the giant panda (Ailuropoda melanoleuca) nature reserve network in China was initiated in the 1960s, though the effort to create new reserves boomed considerably after the year 2000. Given this rapid development of protected areas in panda habitats, and the potential conflicting interests between conservation administrations and local economic development, it is essential to assess the role of new nature reserves in the overall giant panda conservation effort and reserve network. We utilized data from national giant panda surveys conducted in 2000 and 2012 to compare the size, spatial use, and distribution of panda populations, as well as the habitat suitability and connectivity in the Northern Qionglai Mountains between the two survey years. Our results show that although the total giant panda population in the study area did not change remarkably, local changes did occur. Most notably, the population in Wolong Nature Reserve declined by 27.3% (N = 39) and the population in Caopo Nature Reserve increased by 71.4% (N = 29) over the 12-year study period. We also found habitat suitability and availability decreased in both Wolong (12.4%) and Caopo (7.4%), but that the relative density of giant pandas declined (19.2%) and increased (84.6%) at each site, respectively. The distance between centers of high IUA were more distant in 2012 (14.1±1.9km) than that in 2000 (6.1±0.9km; t = -7.4, df = 5, p = 0.001), showing a scattered spatial pattern. Habitat availability decreased by 42% within the corridor between the two reserves, however panda occurrences in the corridor increased 24.6%. Compared to the total number of encounters, the proportion of the corridor increased 45.76%. Our results show the importance and success of the newly established Caopo to the conservation of giant pandas, and how crucial it is to identify and repair reserve

  7. Effects of a clearcut on the net rates of nitrification and N mineralization in a northern hardwood forest, Catskill Mountains, New York, USA

    USGS Publications Warehouse

    Burns, Douglas A.; Murdoch, Peter S.

    2005-01-01

    The Catskill Mountains of southeastern New York receive among the highest rates of atmospheric nitrogen (N) deposition in eastern North America, and ecosystems in the region may be sensitive to human disturbances that affect the N cycle. We studied the effects of a clearcut in a northern hardwood forest within a 24-ha Catskill watershed on the net rates of N mineralization and nitrification in soil plots during 6 years (1994-1999) that encompassed 3-year pre- and post-harvesting periods. Despite stream NO3- concentrations that increased by more than 1400 ??mol l-1 within 5 months after the clearcut, and three measures of NO3- availability in soil that increased 6- to 8-fold during the 1st year after harvest, the net rates of N mineralization and nitrification as measured by in situ incubation in the soil remained unchanged. The net N-mineralization rate in O-horizon soil was 1- 2 mg N kg-1 day-1 and the net nitrification rate was about 1 mg N kg-1 day-1, and rates in B-horizon soil were only one-fifth to one-tenth those of the O-horizon. These rates were obtained in single 625 m2 plots in the clearcut watershed and reference area, and were confirmed by rate measurements at 6 plots in 1999 that showed little difference in N-mineralization and nitrification rates between the treatment and reference areas. Soil temperature increased 1 ?? 0.8??C in a clearcut study plot relative to a reference plot during the post-harvest period, and soil moisture in the clearcut plot was indistinguishable from that in the reference plot. These results are contrary to the initial hypothesis that the clearcut would cause net rates of these N-cycling processes to increase sharply. The in situ incubation method used in this study isolated the samples from ambient roots and thereby prevented plant N uptake; therefore, the increases in stream NO3- concentrations and export following harvest largely reflect diminished uptake. Changes in temperature and moisture after the clearcut were

  8. Experiments with clustering of catchments in PCA-reduced space and regionalization of a hydrological model (Central Alborz region, Iran)

    NASA Astrophysics Data System (ADS)

    Khosravi, Mohammad; Solomatine, Dimitri; Salajegheh, Ali; Mohseni Saravi, Mohsen; Malekian, Arash; Corzo, Gerald

    2015-04-01

    This study tested the possibility of simulating time series of daily streamflows in ungauged catchments based on climatic and physiographic similarity. The study area is located in central Alborz region in Iran. Fourteen (14) proper catchments, with the area ranged between 16 to 827Km2, in this region selected for testing. After applying Principal Component Analysis for selecting the most important parameters among the different climatic and physiographic parameters, five components which could explain more than 90% of variances of the data were selected and according to the values of the coefficients in selected PCA components, five parameters including: Area, Annual Rainfall, Annual temperature, gravelius compactness coefficient and mean elevation, were selected as the measures for clustering. Then mentioned parameters entered in K-means clustering analysis method to classify the catchments. Finally the catchments divided in three different clusters. Using the well known HBV model, we built a model for the closest catchment to the center of each cluster. Then, the thirteen (13) HBV model parameters were calibrated using Genetic Algorithm. We assumed that the remained catchments in each cluster are ungauged, and using the calibrated model, the daily time series of streamflows simulated in the remained catchments in the considered cluster (as the receiver catchments). Nash Sutcliffe and RMSE indices used to comparing the simulated and recorded data. The experiments with the considered case study confirmed that the model regionalization based on the physiographic and climatic characteristics could be a useful instrument in hydrological studies. Key words: Regionalization, HBV, PCA, Cluster, Catchment, central Alborz region

  9. Evidence for large-magnitude, post-Eocene extension in the northern Shoshone Range, Nevada, and its implications for Carlin-type gold deposits in the lower plate of the Roberts Mountains allochthon

    USGS Publications Warehouse

    Colgan, Joseph P.; Henry, Christopher D.; John, David A.

    2014-01-01

    The northern Shoshone and Toiyabe Ranges in north-central Nevada expose numerous areas of mineralized Paleozoic rock, including major Carlin-type gold deposits at Pipeline and Cortez. Paleozoic rocks in these areas were previously interpreted to have undergone negligible postmineralization extension and tilting, but here we present new data that suggest major post-Eocene extension along west-dipping normal faults. Tertiary rocks in the northern Shoshone Range crop out in two W-NW–trending belts that locally overlie and intrude highly deformed Lower Paleozoic rocks of the Roberts Mountains allochthon. Tertiary exposures in the more extensive, northern belt were interpreted as subvertical breccia pipes (intrusions), but new field data indicate that these “pipes” consist of a 35.8 Ma densely welded dacitic ash flow tuff (informally named the tuff of Mount Lewis) interbedded with sandstones and coarse volcaniclastic deposits. Both tuff and sedimentary rocks strike N-S and dip 30° to 70° E; the steeply dipping compaction foliation in the tuffs was interpreted as subvertical flow foliation in breccia pipes. The southern belt along Mill Creek, previously mapped as undivided welded tuff, includes the tuff of Cove mine (34.4 Ma) and unit B of the Bates Mountain Tuff (30.6 Ma). These tuffs dip 30° to 50° east, suggesting that their west-dipping contacts with underlying Paleozoic rocks (previously mapped as depositional) are normal faults. Tertiary rocks in both belts were deposited on Paleozoic basement and none appear to be breccia pipes. We infer that their present east tilt is due to extension on west-dipping normal faults. Some of these faults may be the northern strands of middle Miocene (ca. 16 Ma) faults that cut and tilted the 34.0 Ma Caetano caldera ~40° east in the central Shoshone Range (

  10. Upper Jurassic mafic magmatic rocks of the eastern Klamath Mountains, northern California: remnant of a volcanic arc built on young continental crust

    USGS Publications Warehouse

    Brouxel, M.; Lapierre, H.; Zimmermann, J.-L.

    1989-01-01

    Diabasic and gabbroic dikes intruding the lower Paleozoic Trinity Ophiolite in the Lovers Leap section, Klamath Mountains, California, display strong calc-alkalic petrological and geochemical features. These dikes, of Late Jurassic age (149??6Ma by K/Ar), are petrographically and geochemically similar to the contemporaneous calc-alkalic ultramafic magmatism well developed through the Klamath Mountains. They present negative Nb, Zr, and Ti anomalies typical of subduction-related magmatism and probably belong to a volcanic arc on an active continental margin. Values of ??Nd suggest that no old continental crust underlies the Klamath Mountains. -from Authors

  11. The world mountain Damavand: documentation and monitoring of human activities using remote sensing data

    NASA Astrophysics Data System (ADS)

    Kostka, Robert

    The use of different remote sensing data is demonstrated by example of the world mountain, Mt. Damavand (5671 m) in the Alborz Mountains, Iran. Several types of satellite data were required to master the complex task of preparing a monograph of this mountain: SSEOP images of NASA, Russian KFA-1000 pictures, CORONA panoramic images of NASA and Russian KVR-1000 orthoimages. Examples of climatic studies, transportation routes, water resources, conservation areas and relicts of human land-use are presented in order to show the potential of remote sensing data. The right choice of image data is a top priority in applied remote sensing in order to obtain significant results in the documentation and monitoring of human activities.

  12. Fault kinematics and active tectonics at the southeastern boundary of the eastern Alborz (Abr and Khij fault zones): Geodynamic implications for NNE Iran

    NASA Astrophysics Data System (ADS)

    Javidfakhr, Bita; Bellier, Olivier; Shabanian, Esmaeil; Siame, Lionel; Léanni, Laëtitia; Bourlès, Didier; Ahmadian, Seiran

    2011-10-01

    The Alborz is a region of active deformation within the Arabia-Eurasia collision zone. The Abr and the Khij Faults are two NE-trending left-lateral strike-slip faults in the eastern Alborz that correspond to the Shahrud fault system extended through an area of about 95 km × 55 km. Tectonic landforms typically associated with active strike-slip faults, such as deflected stream channels, offset ridges and fault scarps are documented along the mentioned faults. Detailed analyses of satellite images and digital topographic data accompanied by field surveys allowed us to measure horizontal offsets of about 420 ± 50 m and 400 ± 50 m for the Abr and Khij Faults, respectively. A total of 8 quartz-rich samples were sampled and dated from two different fan surfaces using in situ-produced 10Be cosmogenic dating method. Minimum exposure ages for the abandonment of the alluvial fan surfaces of 115 ± 14 kyr along the Abr Fault and of 230 ± 16 kyr along the Khij Fault imply that both faults are active with slip rates of about 3-4 mm yr -1 and 1-3 mm yr -1, respectively. The results of our study provide the first direct quantitative geological estimates of slip rate along these two active faults and place a new constraint on slip distribution between the faults in the eastern Alborz. Fault kinematic studies (from fault slip data) indicate a N35°E-trending maximum stress axis comprising a dominant strike-slip regime in agreement with the geomorphological analyses. The left-lateral strike-slip faulting along the Abr and Khij Faults and their associated fault zones in the eastern Alborz can be due to the westward component of motion of the South Caspian Basin with respect to Eurasia and Central Iran.

  13. Alborz-I array: A simulation on performance and properties of the array around the knee of the cosmic ray spectrum

    NASA Astrophysics Data System (ADS)

    Abdollahi, Soheila; Bahmanabadi, Mahmud; Pezeshkian, Yousef; Mortazavi Moghaddam, Saba

    2016-03-01

    The first phase of the Alborz Observatory Array (Alborz-I) consists of 20 plastic scintillation detectors each one with surface area of 0.25 m2spread over an area of 40 × 40 m2 realized to the study of Extensive Air Showers around the knee at the Sharif University of Technology campus. The first stage of the project including construction and operation of a prototype system has now been completed and the electronics that will be used in the array instrument has been tested under field conditions. In order to achieve a realistic estimate of the array performance, a large number of simulated CORSIKA showers have been used. In the present work, theoretical results obtained in the study of different array layouts and trigger conditions are described. Using Monte Carlo simulations of showers the rate of detected events per day and the trigger probability functions, i.e., the probability for an extensive air shower to trigger a ground based array as a function of the shower core distance to the center of array are presented for energies above 1 TeV and zenith angles up to 60°. Moreover, the angular resolution of the Alborz-I array is obtained.

  14. The Last Glacial Maximum in the Northern European loess belt: Correlations between loess-paleosol sequences and the Dehner Maar core (Eifel Mountains)

    NASA Astrophysics Data System (ADS)

    Zens, Joerg; Krauß, Lydia; Römer, Wolfgang; Klasen, Nicole; Pirson, Stéphane; Schulte, Philipp; Zeeden, Christian; Sirocko, Frank; Lehmkuhl, Frank

    2016-04-01

    The D1 project of the CRC 806 "Our way to Europe" focusses on Central Europe as a destination of modern human dispersal out of Africa. The paleo-environmental conditions along the migration areas are reconstructed by loess-paleosol sequences and lacustrine sediments. Stratigraphy and luminescence dating provide the chronological framework for the correlation of grain size and geochemical data to large-scale climate proxies like isotope ratios and dust content of Greenland ice cores. The reliability of correlations is improved by the development of precise age models of specific marker beds. In this study, we focus on the (terrestrial) Last Glacial Maximum of the Weichselian Upper Pleniglacial which is supposed to be dominated by high wind speeds and an increasing aridity. Especially in the Lower Rhine Embayment (LRE), this period is linked to an extensive erosion event. The disconformity is followed by an intensive cryosol formation. In order to support the stratigraphical observations from the field, luminescence dating and grain size analysis were applied on three loess-paleosol sequences along the northern European loess belt to develop a more reliable chronology and to reconstruct paleo-environmental dynamics. The loess sections were compared to newest results from heavy mineral and grain size analysis from the Dehner Maar core (Eifel Mountains) and correlated to NGRIP records. Volcanic minerals can be found in the Dehner Maar core from a visible tephra layer at 27.8 ka up to ~25 ka. They can be correlated to the Eltville Tephra found in loess section. New quartz luminescence ages from Romont (Belgium) surrounding the tephra dated the deposition between 25.0 + 2.3 ka and 25.8 + 2.4 ka. In the following, heavy minerals show an increasing importance of strong easterly winds during the second Greenland dust peak (~24 ka b2k) correlating with an extensive erosion event in the LRE. Luminescence dating on quartz bracketing the following soil formation yielded ages of

  15. 2.8-Ma ash-flow caldera at Chegem River in the northern Caucasus Mountains (Russia), contemporaneous granites, and associated ore deposits

    USGS Publications Warehouse

    Lipman, P.W.; Bogatikov, O.A.; Tsvetkov, A.A.; Gazis, C.; Gurbanov, A.G.; Hon, K.; Koronovsky, N.V.; Kovalenko, V.I.; Marchev, P.

    1993-01-01

    Diverse latest Pliocene volcanic and plutonic rocks in the north-central Caucasus Mountains of southern Russia are newly interpreted as components of a large caldera system that erupted a compositionally zoned rhyolite-dacite ash-flow sheet at 2.83 ?? 0.02 Ma (sanidine and biotite 40Ar/39Ar). Despite its location within a cratonic collision zone, the Chegem system is structurally and petrologically similar to typical calderas of continental-margin volcanic arcs. Erosional remnants of the outflow Chegem Tuff sheet extend at least 50 km north from the source caldera in the upper Chegem River. These outflow remnants were previously interpreted by others as erupted from several local vents, but petrologic similarities indicate a common origin and correlation with thick intracaldera Chegem Tuff. The 11 ?? 15 km caldera and associated intrusions are superbly exposed over a vertical range of 2,300 m in deep canyons above treeline (elev. to 3,800 m). Densely welded intracaldera Chegem Tuff, previously described by others as a rhyolite lava plateau, forms a single cooling unit, is > 2 km thick, and contains large slide blocks from the caldera walls. Caldera subsidence was accommodated along several concentric ring fractures. No prevolcanic floor is exposed within the central core of the caldera. The caldera-filling tuff is overlain by andesitic lavas and cut by a 2.84 ?? 0.03-Ma porphyritic granodiorite intrusion that has a cooling age analytically indistinguishable from that of the tuffs. The Eldjurta Granite, a pluton exposed low in the next large canyon (Baksan River) 10 km to the northwest of the caldera, yields variable K-feldspar and biotite ages (2.8 to 1.0 Ma) through a 5-km vertical range in surface and drill-hole samples. These variable dates appear to record a prolonged complex cooling history within upper parts of another caldera-related pluton. Major W-Mo ore deposits at the Tirniauz mine are hosted in skarns and hornfels along the roof of the Eldjurta Granite

  16. STRAWBERRY MOUNTAIN WILDERNESS, OREGON.

    USGS Publications Warehouse

    Thayer, T.P.; Stotelmeyer, Ronald B.

    1984-01-01

    The Strawberry Mountain Wilderness extends 18 mi along the crest of the Strawberry Range and comprises about 53 sq mi in the Malheur National Forest, Grant County, Oregon. Systematic geologic mapping, geochemical sampling and detailed sampling of prospect workings was done. A demonstrated copper resource in small quartz veins averaging at most 0. 33 percent copper with traces of silver occurs in shear zones in gabbro. Two small areas with substantiated potential for chrome occur near the northern edge of the wilderness. There is little promise for the occurrence of additional mineral or energy resources in the Strawberry Mountain Wilderness.

  17. Llandovery green/grey and black mudrock facies of the northern Holy Cross Mountains (Poland) and their relation to early Silurian sea-level changes and benthic oxygen level

    NASA Astrophysics Data System (ADS)

    Trela, Wiesław; Podhalańska, Teresa; Smolarek, Justyna; Marynowski, Leszek

    2016-08-01

    The Llandovery mudrock facies in the northern Holy Cross Mountains reveal lithological variability allowing their interpretation in the context of post-Ordovician climate and sea-level changes in the Caledonian foredeep basin developed along the present SW margin of Baltica. They form a succession up to 50 m thick made up of grey and greenish clayey mudstones interrupted by black shales. The sedimentary and geochemical data (total organic carbon, pyrite framboids and trace metals) clearly show that the black shales document periods of the significant sediment starvation and oxygen- deficient conditions. Their occurrence is confined to the persculptus-acuminatus, vesiculosus, cyphus, convolutus-sedgwickii, turriculatus-crispus, crenulata and spiralis graptolite biozones and they can be correlated with post-glacial transgressions. In contrast, the grey and greenish mudstones are interpreted as lithofacies reflecting permanent benthic oxygenation driven by deep-water ventilation during the Aeronian and Telychian regressions supported by sedimentary and geochemical studies, and diameters of pyrite framboids

  18. A summary of the U.S. Geological Survey 1999 resource assessment of selected coal zones in the Northern Rocky Mountains and Great Plains region, Wyoming, Montana, and North Dakota

    USGS Publications Warehouse

    Ellis, M.S.; Nichols, D.J.

    2002-01-01

    In 1999, 1,100 million short tons of coal were produced in the United States, 38 percent from the Northern Rocky Mountains and Great Plains region. This coal has low ash content, and sulfur content is in compliance with Clean Air Act standards (U.S. Statutes at Large, 1990).The National Coal Resource Assessment for this region includes geologic, stratigraphic, palynologic, and geochemical studies and resource calculations for 18 major coal zones in the Powder River, Williston, Green River, Hanna, and Carbon Basins. Calculated resources are 660,000 million short tons. Results of the study are available in U.S. Geological Survey Professional Paper 1625?A (Fort Union Coal Assess-ment Team, 1999) and Open-File Report 99-376 (Flores and others, 1999) in CD-ROM format.

  19. Depositional framework and regional correlation of pre-Carboniferous metacarbonate rocks of the Snowden Mountain area, central Brooks Range, Northern Alaska

    USGS Publications Warehouse

    Dumoulin, J.A.; Harris, A.G.

    1994-01-01

    This report describes lithofacies, conodont biostratigraphy and biofacies, and depositional environments of Proterozoic(?) through Devonian metacarbonate rocks in the Snowden Mountain area. These rocks are correlated with successions on the Seward Peninsula and across the Brooks Range. Lithologic and paleobiogeographic data suggest that these successions formed along a single continental margin which had faunal exchange with both North America and Siberia, rather than on a series of discrete platforms juxtaposed by later tectonic events.

  20. Granodiorites of the South Mountain Batholith (Nova Scotia, Canada) derived by partial melting of Avalonia granulite rocks beneath the Meguma terrane: Implications for the heat source of the Late Devonian granites of the Northern Appalachians

    NASA Astrophysics Data System (ADS)

    Shellnutt, J. Gregory; Dostal, Jaroslav

    2015-08-01

    The Late Devonian South Mountain Batholith (SMB) of Nova Scotia is the largest batholith of the northern Appalachians. The peraluminous granitic rocks range from biotite granodiorite to leucogranite. Samples collected from a drill core of the Scrag Lake granodioritic pluton of the western SMB are chemically homogeneous from the surface to a depth of ~ 1425 m. The homogeneous composition implies that the granodiorite was derived from a relatively homogeneous source and that country rock assimilation was not an important source for the parental magma. Equilibrium partial melt modeling of underlying sub-Meguma granulite rocks indicates that they are the primary source rocks of the granodiorites. We suggest that mantle-derived magmas intruded the lower crust and induce large-scale melting of the granulite basement rocks to produce the granodiorites. Fractional crystallization of the granodiorites plus assimilation of Meguma Supergroup metasediments likely produces the silica-rich rocks of the SMB. The cause of mantle melting is uncertain however it may be related to the transitioning of the northern Appalachians from a position above the deep mantle Pacific large low shear velocity province (LLSVP) to a higher shear velocity region of the mantle.

  1. Quality, Safety and Patient Centered Care--A Dream Come True in the Mountains of Northern Pakistan. An Award winning project of "2015 Quality, Safety & Patient Centered Care Award" at, Chicago USA.

    PubMed

    Jassani, Kashif; Essani, Rozina Roshan; Abbas, Syed Nadeem Husain

    2016-01-01

    Northern Pakistan remains very challenging terrain due to harsh weather all year round presenting an infrastructura, human resource and supply chain challenge of its own. Many times the facility had to move to different locations on emergency and ad hoc basis due to landslides, earthquakes affecting continuity of care. Providing quality healthcare to often resource constraint hard-to-reach areas has always been AKHS,P's unique forte. Breaking barriers for catchment population to access quality healthcare, AKHS,P embarked on an initiative of implementing, achieving and sustaining ISO 9001:2008 Quality Management System international standards certification. This article shares the unique experience of AKHS,P in achieving and sustaining ISO 9001:2008 International Quality Management System Certification. After untiring efforts and the hard work of ground staff; AKHS,P achieved ISO 9001:2008 International Quality Management System Certification as well as 1st Surveillance Audit which itself proved that AKHS,P sustained quality systems and ensured continuous quality improvement in the Mountains of Northern Pakistan. PMID:27180469

  2. Geometry and Kinematics of Thrust Tectonics of the Northern Longmenshan Mountains: Constraints for the Multi-phase Uplifting and Spreading of the Southeast Boundary of Qinghai-Tibet Plateau

    NASA Astrophysics Data System (ADS)

    He, Dengfa; John, Suppe; chen, Longbo

    2015-04-01

    The Longmenshan Mountains thrust belt (LMSTB) is the southeastern boundary of the Qinghai-Tibetan plateau (QTP). To study its structural geometry and kinematics is of great significance to constrain the formation mechanism and evolution processes of the Qinghai-Tibetan plateau. Bounded by Guanxian and Anxian area, LMSTB is subdivided into three segments from SW to NE (i.e., the southern, middle and northern segment). The northern Longmenshan segment, lying around Anxian to Guangyuan area, is located at the southwestern end of the Qinling Orogenic Belt and the northeastern end of the Songpan-Ganzi folded belt, and is connected with the Bikou block and the Micangshan thrust belt at its northernmost part, which leads to a distinct superimposed tectonic setting for it. By employing the sandstone apatite fission track (AFT) and electron spin resonance (ESR), together with the study of regional unconformities and strata development, the paper analyzes the differential uplifting history and the uplifting migration processes in different area. Based on the surface geology, and the high resolution seismic profiles and drilling data, the fault arrays, the structural style and its variations in this area are studied and by balanced geological cross-section restoration, the kinematics with time of these faults is discussed. It shows that prior to the Late Triassic, the tectonic setting was extensional at the northern Longmenshan. Yet, at the early stage of the Late Triassic, it transited to be compressional and experienced tectonic inversion, which made the Upper Triassic Xujiahe Formation (T3x) lies above the Middle Triassic Leikoupo Formation (T2l) with a lower angular unconformity. When came to the end of the depositional period of the third member of T3x, the northern Longmenshan began to uplift regionally, which resulted in the lower-angular unconformities and disconformities between T3x3 and T3x4. At the end of the T3x, the northern Longmenshan experienced intensive

  3. Christmas Mountains

    Atmospheric Science Data Center

    2013-04-17

    article title:  Christmas Mountains     View Larger Image ... New Brunswick. Located above image center are the Christmas Mountains, a region of old-growth forest nestled in a remote wilderness. Within ...

  4. Divisions of potential fracture permeability, based on distribution of structures and linear features in sedimentary rocks, northern Great Plains-Rocky Mountains region of Montana, North Dakota, South Dakota, Wyoming, and northern Nebraska

    USGS Publications Warehouse

    Cooley, Maurice E.

    1986-01-01

    Division of fracture traces in sedimentary rocks of Cenozoic to Precambrian Age - Eastern and central North and South Dakota and northern Nebraska include only Cenozoic to Pennsylvanian rocks at the surface and at relatively shallow depths; the area of shallow thrust faulting in north-central Montana includes many Cretaceous rocks. Fractures in the deeper rocks in these areas vary, depending on the local structure. Large areas of western Montana are underlain by Precambrian sedimentary rocks. 

  5. Significance of xenocrystic Precambrian zircon contained within the southern continuation of the Josephine ophiolite: Devils Elbow ophiolite remnant, Klamath Mountains, northern California

    NASA Astrophysics Data System (ADS)

    Wright, James E.; Wyld, Sandra J.

    1986-08-01

    The Josephine ophiolite of the western Jurassic belt, Klamath Mountain province of California and Oregon, is the expression of a well-documented Late Jurassic suprasubduction zone rift basin that formed between an active Late Jurassic arc to the west and a remnant Middle Jurassic arc to the east. The Devils Elbow ophiolite remnant (DEO) exposed along the South Fork of the Trinity River represents the southernmost continuation of the Josephine ophiolite and provides important new constraints on the early history of this rift basin. The DEO consists of pillow lavas and breccias and a well-developed sheeted dike complex that are depositionally overlain by a clast-supported breccia derived almost exclusively from ophiolitic detritus. Dikes and irregular pods of plagiogranite are conspicuous elements of the DEO and exhibit mutually crosscutting relations with mafic dikes; thus, they are interpreted as genetically related elements of the dike complex. Zircon separates from two widely separated plagiogranite dike localities yielded two distinct zircon populations: a clear, euhedral, magmatic population and a reddish, rounded xenocrystic population. The isotopic systematics of four zircon fractions from these two dike localities indicate a crystallization age for the DEO of 164 ±1 Ma and an age of ˜1.7 Ga for the xenocrystic zircon component. The occurrence of a xenocrystic Precambrian zircon component within the plagiogranites of the DEO provides unequivocal evidence that rifting occurred within preexisting zircon-bearing crustal rocks of the Klamath Mountains. As there is no Precambrian crust within the Klamath Mountains, the xenocrystic zircon population must have been derived from supracrustal sedimentary sequences. The most likely source for the older zircon component is a terrigenous metasedimentary sequence contained within the Rattlesnake Creek terrane, which formed part of the structural basement of the rifted Middle Jurassic arc. The incorporation of

  6. A 9000 year perspective on carbon accumulation rates under changing hydro-climate and vegetation conditions in a mountain peatland, northern Carpathians, Romania

    NASA Astrophysics Data System (ADS)

    Feurdean, Angelica; Panait, Andrei; Gałka, Mariusz; Diaconu, Andrei; Hutchinson, Simon; Mulch, Andreas; Tantau, Ioan; Hickler, Thomas

    2016-04-01

    Peatlands, in particular ombrogenous bogs, which entirely depend on water from precipitation, are sensitive to changes in the balance between precipitation and evapotranspiration; and therefore highly suitable for hydro-climatological reconstruction. Peatlands also represent a large carbon pool in the terrestrial biosphere. However, little is known about the C sequestration processes in mountain peatlands under various competing drivers of change (climate, vegetation, fire). We applied a multi-proxy approach (bulk density, loss on ignition, total organic carbon, testate amoebae, δ13C in Sphagnum, plant macrofossils, pollen and charcoal) to a peat sequence from a mountain ombrogenous bog (Tǎul Muced) to explore how changes in hydro-climate conditions, peat plant composition and fire have affected long-term physical peat properties and the rate of carbon accumulation over the last 9000 years. Carbon accumulation at this site ranged from 7 to 105 g C cm2 yr1 (mean 23 ± 14 g C cm2 yr_1). We found that high moisture availability (P-E) as inferred from testate amoebae and δ13C values in Sphagnum increased the carbon sink capacity of peatland. The strength of the relationship between the rate of carbon accumulation and climate appears particularly evident over the last millennium when high C accumulation rates correlated with the warm and wet conditions of the Medieval Climate Anomaly and lower C accumulation rates with the dry conditions of the Little Ice Age. We also found a significant positive correlation between the rate of C accumulation and changes in vegetation; rates were lowest (17 g C cm2 yr_1), during periods of mixed Sphagnum (primarily S. magellanicum and S. angustifolium) and vascular plant (Cyperaceae, Eriophorum vaginatum) growth and increased (31 g C cm2 yr_1) during the accumulation of Sphagnum peat, regardless the dominant Sphagnum species. We did not find indication of peatland fire during the investigated interval. Our study represents one of the

  7. Integration of geology, non-seismic geophysics and seismic data in a structurally complex, frontier oil play: Northern Sangre de Cristo Mountains/Northeast San Luis Basin, Colorado

    SciTech Connect

    Watkins, T.A.; Belcher, J.S.; Gries, R.

    1995-06-01

    The discovery of live Cretaceous oil in mineral exploration drill holes, followed by the identification of Mesozoic sediments in outcrop and in shallow drill holes, has lead to an integrated approach to exploration of a structurally complex, frontier oil play in south-central Colorado. Gravity, aeromagnetic, magnetotelluric (MT), and time domain electromagnetic (TDEM) data were acquired and interpreted in the initial stages of the project. Models derived from the geophysical data were augmented with geologic field work to explain specific anomalies. Interpretation of the gravity data was constrained by density measurements on representative rock samples collected in the field. Seismic data, acquired in the most recent exploration stage, provided confirmation and modification of the basin margin geometry. Velocity data from the seismic was integrated with resistivity, density, magnetic and geologic data to predict lithologies on an intermediate fault block located between the Sangre de Cristo Mountains and the San Luis Basin.

  8. Northern San Andreas Fault slip rates on the Santa Cruz Mountain section: 10Be dating of an offset alluvial fan complex, Sanborn County Park, Saratoga, CA

    NASA Astrophysics Data System (ADS)

    Guns, K. A.; Prentice, C. S.; DeLong, S. B.; Kiefer, K.; Blisniuk, K.; Burgmann, R.

    2015-12-01

    To better assess seismic hazard and fault behavior along the southern peninsula in the San Francisco Bay Area on the Santa Cruz Mountain section of the San Andreas Fault, we combine field observations and high-resolution lidar topography data with 10Be exposure dating on offset landforms to estimate geologic fault slip rates. Our mapping at Sanborn County Park near Saratoga reveals a progression of alluvial fans and debris flows offset from their upstream sources by dextral slip on the San Andreas Fault. These upstream sources are 3 drainages, Todd Creek, Service Road Creek and Aubry Creek. Coarse alluvial deposits from each of these creeks contain large Tertiary sandstone boulders of varying size and abundance, derived from the Vaqueros Formation, that allow us to constrain the provenance of offset alluvial deposits to their upstream sources. Initial reconstruction, based on clast-count data on lithology and size from Todd Creek (n=68), Service Road Creek (N=32) and the offset deposits (n=68), suggest ≥140 m of dextral fault movement. Initial 10Be cosmogenic dating of sandstone boulders on an offset deposit from Service Road Creek yields a maximum date of 8 ka, a date uncorrected for hillslope residence and fluvial transport of inherited 10Be concentrations. These data suggest a minimum slip rate of at least 17 mm/yr on the Santa Cruz Mountain section of the San Andreas Fault in the peninsula. Ongoing analysis will refine this fault slip rate. Our preliminary data underscore the potential of this site to provide geologic slip rate estimates, and therefore answer a question critical to seismic hazard assessment, in a region where steep terrain, mass wasting, vegetation and urban development have generally made slip rate estimates challenging to obtain.

  9. Thermal evolution of a portion of the Sevier hinterland: The northern Ruby Mountains - east Humboldt Range and Wood Hills, northwestern Nevada

    NASA Astrophysics Data System (ADS)

    Hodges, K. V.; Snoke, A. W.; Hurlow, H. A.

    1992-02-01

    Conventional thermobarometry and Gibbs' Method modeling have been used to obtain new information pertaining to the Mesozoic-Tertiary thermal evolution of the Ruby Mountains-East Humboldt Range and Wood Hills metamorphic complexes, northeastern Nevada. Kyanite-grade assemblages from Clover Hill, in the extreme northeastern part of the East Humboldt Range, were produced at temperatures of 780-810 K and depths in excess of 35 km; previously published geochronologic data suggest an Early Cretaceous or Late Jurassic age for this event. The Clover Hill area subsequently experienced a major unroofing interval prior to Late Cretaceous time, during which it was brought roughly 20 km closer to the surface. The lack of stratigraphic evidence for substantial Cretaceous erosion in the region and the topology of the pressure-temperature paths for the Clover Hill samples suggest that the unroofing mechanism may have been tectonic denudation related to the relaxation of large topographic gradients produced by crustal thickening in the hinterland of the Sevier orogen. Metamorphic rocks at Clover Hill and within the Wood Hills core complex equilibrated at 820-900 K and 500-640 MPa (18-24 km) in Cretaceous time, prior to 115 Ma. Other parts of the Ruby Mountains-East Humboldt Range metamorphic complex, presently structurally separated from the Clover Hill sequence, were intruded extensively by Late Cretaceous granitic magmas and attained substantially higher temperatures than the Clover Hill-Wood Hills block. Sillimanite-grade assemblages from these areas apparently underwent roughly 10 km of unroofing and 130 K of cooling prior to final equilibration at 820-920 K and 360-430 MPa (13-16 km) during Oligocene extension.

  10. A late Frasnian (Late Devonian) radiolarian, sponge spicule, and conodont fauna from the Slaven Chert, northern Shoshone Range, Roberts Mountains allochthon, Nevada

    USGS Publications Warehouse

    Boundy-Sanders, S. Q.; Sandberg, C.A.; Murchey, B.L.; Harris, A.G.

    1999-01-01

    Co-occuring conodonts, radiolarians, and sponge spicules from the type locality of the Slaven Chert, northern Shoshone Range, Nevada, indicate that the radiolarian and sponge spicule assemblage described herein correlates with the Late rhenana conodont Zone (late Frasnian). The moderately well preserved radiolarians are the first Frasnian-age fauna described from the Western Hemisphere. They include spumellarians, Ceratoikiscum, and Paleoscenidium, and a radiolarian which we have assigned to a new genus, Durahelenifore Boundy-Sanders and Murchey, with its type species, Durahelenifore robustum Boundy-Sanders and Murchey. Sponge spicules include umbellate microscleres of the Subclass Amphidiscophora, Order Hemidiscosa, previously documented only in Pennsylvanian and younger rocks.

  11. Understanding the role of wildland fire, insects, and disease in predicting climate change effects on whitebark pine: Simulating vegetation, disturbance, and climate dynamics in a northern Rocky Mountain landscape

    NASA Astrophysics Data System (ADS)

    Keane, R. E.; Loehman, R.

    2010-12-01

    Climate changes are projected to profoundly influence vegetation patterns and community compositions, either directly through increased species mortality and shifts in species distributions, or indirectly through disturbance dynamics such as increased wildfire activity and extent, shifting fire regimes, and pathogenesis. High-elevation landscapes have been shown to be particularly sensitive to climatic change, and are likely to experience significant impacts under predicted future climate change conditions. Whitebark pine (Pinus albicaulis), a high-elevation five-needle pine species that is important for snowpack retention, resource provision, and other ecosystem services in alpine environments in the northern Rocky Mountains, is particularly sensitive to an interacting complex of disturbances - climatic change, altered fire regimes, white-pine blister rust, and mountain pine beetles - that have already caused major changes in species distribution and density. Further changes in abiotic and biotic conditions will likely pose additional threats to the success of this keystone alpine tree species. We used the mechanistic simulation model Fire-BGCv2 to assess potential interacting effects of climate changes, pathogens, and wildfire on the distribution and density of whitebark pine in a high-elevation watershed in Glacier National Park, Montana, USA. The FireBGCv2 modeling platform is uniquely structured to address questions of future species distribution in response to interacting disturbance agents; further, we integrated a range of potential future climate conditions derived from downscaled Global Circulation Models to examine multiple potential future climatic contexts. Our results show that the distribution of whitebark pine is severely reduced under potential future climates, and that increased fire frequency and severity resulting from warmer, drier conditions further reduces the presence of the species on the simulation landscape. Simulation model results

  12. Results from Geothermal Logging, Air and Core-Water Chemistry Sampling, Air Injection Testing and Tracer Testing in the Northern Ghost Dance Fault, YUCCA Mountain, Nevada, November 1996 to August 1998

    SciTech Connect

    Lecain, G.D.; Anna, L.O.; Fahy, M.F.

    1998-08-01

    Geothermal logging, air and core-water chemistry sampling, air-injection testing, and tracer testing were done in the northern Ghost Dance Fault at Yucca Mountain, Nevada, from November 1996 to August 1998. The study was done by the U.S. Geological Survey, in cooperation with the U.S. Department of Energy. The fault-testing drill room and test boreholes were located in the crystal-poor, middle nonlithophysal zone of the Topopah Spring Tuff, a tuff deposit of Miocene age. The drill room is located off the Yucca Mountain underground Exploratory Studies Facility at about 230 meters below ground surface. Borehole geothermal logging identified a temperature decrease of 0.1 degree Celsius near the Ghost Dance Fault. The temperature decrease could indicate movement of cooler air or water, or both, down the fault, or it may be due to drilling-induced evaporative or adiabatic cooling. In-situ pneumatic pressure monitoring indicated that barometric pressure changes were transmitted from the ground surface to depth through the Ghost Dance Fault. Values of carbon dioxide and delta carbon-13 from gas samples indicated that air from the underground drill room had penetrated the tuff, supporting the concept of a well-developed fracture system. Uncorrected carbon-14-age estimates from gas samples ranged from 2,400 to 4,500 years. Tritium levels in borehole core water indicated that the fault may have been a conduit for the transport of water from the ground surface to depth during the last 100 years.

  13. Evaluation of soil erosion as a basis of sediment yield in mountainous catchments: a preliminary study in the River Douro Basin (Northern Portugal)

    NASA Astrophysics Data System (ADS)

    Reis, Anabela; Martinho Lourenço, José M.; Parker, Andrew; Alencoão, Ana

    2013-04-01

    The River Corgo drains a meso-scale mountainous rural catchment with an area of 295 km2, underlain by crystalline rocks, in a temperate climate, which integrates the transboundary River Douro Basin, in the northeast of Portugal. A geochemical survey on oxic fluvial sediments of the river network shows considerable contents of metals associated to the finer particles (< 63um). The results on the study of the sediment properties indicate that these are essentially detrital in origin, derived from soils and weathering products. Moreover, taking into account the hydrological pattern of the catchment, the seasonal and spatial variability of metal contents associated to the sediments suggests that the control of metal in the sediments by their mineralogical, geochemical and physical properties is governed primarily at the level of the basin soils system, especially in the Wet Period, when the sediments are frequently remobilised (Reis, 2010). Although the soil particles are a common pathway of transport and entrance of metals in the fluvial network by runoff derived erosion, this mechanism is naturally more marked in mountainous catchments. Modelling sediment and adsorbed contaminant transport within catchments can help to identify possible contaminant sources, as well as to estimate the delivered quantities of eroded material and associated contaminants. In catchments with the described morphological features, monitoring the transport of sediments poses some issues concerning: (a) the low mass yield of suspended sediment from river water, under low-flow conditions; (b) the maintenance of the sediment sampler's devices in the streams, in periods of high-flow or storm events. This study describes the preliminary results of a GIS-based mass balance model of overland sediment transport to the River. The erosion, the first step of sediment transport, was estimated by an empirical model - The Universal Soil Loss Equation (USLE). The objective was to construct a GIS based

  14. The Glacier National Park GLORIA Project: A new US Target Region for Alpine Plant Monitoring Installed in the Northern Rocky Mountains, Montana

    NASA Astrophysics Data System (ADS)

    Holzer, K.; Fagre, D.

    2004-12-01

    The Global Observation Research Initiative in Alpine Environments (GLORIA) is an international research network whose purpose is to assess climate change impacts on vegetation in alpine environments worldwide. A standard protocol was developed by the international office in Vienna, Austria, and has specific site requirements and techniques that allow sites to be compared worldwide. This protocol requires four summits to be selected within a target region, covering zonal differences of subalpine to nival, and on each of these summits intensive vegetation plots are set up and monitored on a five year interval. Only three target regions in North America have been completed to date, one in Glacier National Park, Montana, and the other two in the Sierra Nevada and White Mountains, California. The four GLORIA summit plots in Glacier National Park were completed over the summers of 2003 and 2004. Because the Continental Divide bisects Glacier National Park (north to south), we chose summits only East of the divide to stay within a similar climatic pattern. Establishing sites was difficult due to the steep and rocky glaciated terrain and the remoteness of suitable sites that required multi-day approaches. Our highest summit (Seward Mtn. 2717 m) is the northernmost and our lowest summit (Dancing Lady Mtn. 2245 m) is southernmost. Treeline is strongly influenced by terrain and is significantly more variable than in the central Rocky Mountains. This also was true of zonal differences of alpine vegetation. Subalpine and even grassland species were found on the same summits as upper alpine species and areas considered subnival. While different zonal areas often occurred on one summit, they were highly influenced by the aspect and slope of that summit area. Between 51 and 82 vascular plants were documented on each summit. There was a high degree of variability in species diversity and percent cover on each summit that was correlated to directional exposure. The summit morphology

  15. Holocene earthquakes and right-lateral slip on the left-lateral Darrington-Devils Mountain fault zone, northern Puget Sound, Washington

    USGS Publications Warehouse

    Personius, Stephen F.; Briggs, Richard W.; Nelson, Alan R.; Schermer, Elizabeth R; Maharrey, J. Zebulon; Sherrod, Brian; Spaulding, Sarah A.; Bradley, Lee-Ann

    2014-01-01

    Sources of seismic hazard in the Puget Sound region of northwestern Washington include deep earthquakes associated with the Cascadia subduction zone, and shallow earthquakes associated with some of the numerous crustal (upper-plate) faults that crisscross the region. Our paleoseismic investigations on one of the more prominent crustal faults, the Darrington–Devils Mountain fault zone, included trenching of fault scarps developed on latest Pleistocene glacial sediments and analysis of cores from an adjacent wetland near Lake Creek, 14 km southeast of Mount Vernon, Washington. Trench excavations revealed evidence of a single earthquake, radiocarbon dated to ca. 2 ka, but extensive burrowing and root mixing of sediments within 50–100 cm of the ground surface may have destroyed evidence of other earthquakes. Cores in a small wetland adjacent to our trench site provided stratigraphic evidence (formation of a laterally extensive, prograding wedge of hillslope colluvium) of an earthquake ca. 2 ka, which we interpret to be the same earthquake documented in the trenches. A similar colluvial wedge lower in the wetland section provides possible evidence for a second earthquake dated to ca. 8 ka. Three-dimensional trenching techniques revealed evidence for 2.2 ± 1.1 m of right-lateral offset of a glacial outwash channel margin, and 45–70 cm of north-side-up vertical separation across the fault zone. These offsets indicate a net slip vector of 2.3 ± 1.1 m, plunging 14° west on a 286°-striking, 90°-dipping fault plane. The dominant right-lateral sense of slip is supported by the presence of numerous Riedel R shears preserved in two of our trenches, and probable right-lateral offset of a distinctive bedrock fault zone in a third trench. Holocene north-side-up, right-lateral oblique slip is opposite the south-side-up, left-lateral oblique sense of slip inferred from geologic mapping of Eocene and older rocks along the fault zone. The cause of this slip reversal is

  16. VeWa: Assessing Vegetation Effects on Water Flows and Mixing in Northern Mountain Environments using Stable Isotopes and Conceptual Runoff Models

    NASA Astrophysics Data System (ADS)

    Tetzlaff, D.; Buttle, J. M.; Carey, S. K.; Laudon, H.; McDonnell, J.; McNamara, J. P.; Van Huijgevoort, M.; Spence, C.; Soulsby, C.

    2015-12-01

    The lack of comprehensive tracer data sets still hinders the development of a generalized understanding of how northern headwaters function hydrologically. As part of the ERC funded "VeWa" project, we combined a conceptual rainfall-runoff model and input-output relationships of stable isotopes to understand ecohydrological influences on hydrological partitioning in in six high-latitude experimental catchments located in the UK, USA, Sweden and Canada. We used stable isotope records from precipitation and stream flow to examine the effects of soils and landcover. A meta-analysis was carried out using the HBV-model to estimate the main storage changes characterising annual water balances. Annual snowpack storage importance was ranked differently across the sites, and the subsequent rate and longevity of melt was reflected in calibrated parameters that determine partitioning of waters between more rapid and slower flowpaths and associated variations in soil and groundwater storage. Variability of stream water isotopic composition depends on: (i) rate and duration of spring snowmelt; (ii) significance of summer/autumn rainfall; (iii) relative importance of near-surface and deeper flowpaths in routing water to the stream. Flowpath partitioning also regulates influences of summer evaporation on drainage waters. Deviations of isotope data from the Global Meteoric Water Line showed subtle effects of internal catchment processes on isotopic fractionation most likely through evaporation. After accounting for climate, evaporative fractionation is strongest at sites where lakes and near-surface runoff processes in wet riparian soils can mobilize isotopically-enriched water during summer and autumn. Given close soil-vegetation coupling, this may result in spatial variability in soil water isotope pools available for plant uptake. We argue that stable isotope studies are crucial in addressing the many open questions on hydrological functioning of northern environments.

  17. Human impacts to mountain streams

    NASA Astrophysics Data System (ADS)

    Wohl, Ellen

    2006-09-01

    Mountain streams are here defined as channel networks within mountainous regions of the world. This definition encompasses tremendous diversity of physical and biological conditions, as well as history of land use. Human effects on mountain streams may result from activities undertaken within the stream channel that directly alter channel geometry, the dynamics of water and sediment movement, contaminants in the stream, or aquatic and riparian communities. Examples include channelization, construction of grade-control structures or check dams, removal of beavers, and placer mining. Human effects can also result from activities within the watershed that indirectly affect streams by altering the movement of water, sediment, and contaminants into the channel. Deforestation, cropping, grazing, land drainage, and urbanization are among the land uses that indirectly alter stream processes. An overview of the relative intensity of human impacts to mountain streams is provided by a table summarizing human effects on each of the major mountainous regions with respect to five categories: flow regulation, biotic integrity, water pollution, channel alteration, and land use. This table indicates that very few mountains have streams not at least moderately affected by land use. The least affected mountainous regions are those at very high or very low latitudes, although our scientific ignorance of conditions in low-latitude mountains in particular means that streams in these mountains might be more altered than is widely recognized. Four case studies from northern Sweden (arctic region), Colorado Front Range (semiarid temperate region), Swiss Alps (humid temperate region), and Papua New Guinea (humid tropics) are also used to explore in detail the history and effects on rivers of human activities in mountainous regions. The overview and case studies indicate that mountain streams must be managed with particular attention to upstream/downstream connections, hillslope

  18. Liquefaction Hazard Maps for Three Earthquake Scenarios for the Communities of San Jose, Campbell, Cupertino, Los Altos, Los Gatos, Milpitas, Mountain View, Palo Alto, Santa Clara, Saratoga, and Sunnyvale, Northern Santa Clara County, California

    USGS Publications Warehouse

    Holzer, Thomas L.; Noce, Thomas E.; Bennett, Michael J.

    2008-01-01

    Maps showing the probability of surface manifestations of liquefaction in the northern Santa Clara Valley were prepared with liquefaction probability curves. The area includes the communities of San Jose, Campbell, Cupertino, Los Altos, Los Gatos Milpitas, Mountain View, Palo Alto, Santa Clara, Saratoga, and Sunnyvale. The probability curves were based on complementary cumulative frequency distributions of the liquefaction potential index (LPI) for surficial geologic units in the study area. LPI values were computed with extensive cone penetration test soundings. Maps were developed for three earthquake scenarios, an M7.8 on the San Andreas Fault comparable to the 1906 event, an M6.7 on the Hayward Fault comparable to the 1868 event, and an M6.9 on the Calaveras Fault. Ground motions were estimated with the Boore and Atkinson (2008) attenuation relation. Liquefaction is predicted for all three events in young Holocene levee deposits along the major creeks. Liquefaction probabilities are highest for the M7.8 earthquake, ranging from 0.33 to 0.37 if a 1.5-m deep water table is assumed, and 0.10 to 0.14 if a 5-m deep water table is assumed. Liquefaction probabilities of the other surficial geologic units are less than 0.05. Probabilities for the scenario earthquakes are generally consistent with observations during historical earthquakes.

  19. Geology of the Hog Mountain tonalite and associated lode gold deposits, Northern Alabama Piedmont: Final report for the 1986-1987 project year

    SciTech Connect

    Green, N.L.; Lesher, C.M.

    1988-02-01

    The Hog Mountain tonalite intrudes lower Paleozoic graphitic phyllites of the Wedowee formation and is transgressed by a series of planar, en echelon, bifurcating, auriferous quartz-sulfide veins with well-defined sericite-sulfide alteration envelopes. Least-altered tonalite is white, medium-grained, and weakly to non-foliated. It is characterized by moderately uniform distributions of quartz and oscillatory-normal zoned plagioclase (An/sub 7-41/), with minor amounts of biotite, muscovite, ilmenite, apatite, zircon and corroded garnet; K-feldspar is rare. Least-altered granitoids are peraluminous (A/CNK > 1.15), exhibit significant major- and trace-element variations, are characterized by relatively low REE contents, and have moderately high /delta//sup 18/O (+9.7 to +11.2 %) and uniform /delta/D (-82 to -78 %) values. Biotite log (X/sub Mg//X/sub Fe/)-log(X/sub F//X/sub OH/) relations suggest contamination of an I-type granitic melt by graphitic metapelites. Corroded garnets (Pyr/sub 3/Alm/sub 55/Spess/sub 17/Gross/sub 25/) within the granitoids are chemically-similar to euhedral garnets in adjacent schists and in fine-grained, foliated plagioclase-biotite-muscovite-ilmenite xenoliths, and were probably derived from the metasedimentary host rocks. Equilibration conditions of the xenolith mineral assemblages (465-510/degree/C at ca. 6 kb), calculated using garnet-biotite-muscovite-plagioclase thermobarometry, are similar to inferred metamorphic P-T conditions of underthrusting of Wedowee metasediments to mid-crustal levels during Paleozoic crustal thickening. Observed chemical variations may be modeled by plagioclase/biotite-controlled fractionation of a peraluminous tonalitic melt, accompanied by local cumulus mineral-intercumulus liquid segregation and graphitic metapelite contamination during emplacement. 70 refs., 20 figs.

  20. Origin of high Sr/Y magmas from the northern Taihang Mountains: Implications for Mesozoic porphyry copper mineralization in the North China Craton

    NASA Astrophysics Data System (ADS)

    Gao, Yongfeng; Santosh, M.; Wei, Ruihua; Ma, Guoxi; Chen, Zhikuan; Wu, Jinluan

    2013-12-01

    A number of porphyry Cu deposits have been described from east China which occur in association with Mesozoic high Sr/Y rocks within the continental interior rather than in an arc setting. However, the origin of these high Sr/Y rocks remains controversial. In this study we report precise zircon U-Pb age, as well as major-trace element and Sr-Nd-Pb isotope compositions from the Mujicun Cu mineralized porphyries in the northern Taihang orogen of eastern North China Craton (NCC). LA-ICP-MS zircon U-Pb dating yields an emplacement age of 143 ± 2 Ma, identical to the molybdenite Re-Os isochron ages of 142.5 ± 1.4 Ma for this intrusion. Like most of the Mesozoic adakitic rocks from the eastern NCC, the ore-bearing porphyries and associated volcanic lavas from northern Taihang orogen are rich in large ion lithophile elements and light REE, and have highly differentiated REE patterns. The porphyries and associated volcanic lavas have Sr-Nd-Pb isotopic compositions showing EM1-like isotopic signatures. Such geochemical and isotopic features confirm that the parental magma for these rocks originated from melting of an enriched sub-continental lithospheric mantle source. In comparison to the associated lavas, the ore-bearing porphyries have pronounced low FeO3T, TiO2 and P2O5 contents, and middle-heavy REE (and Y) and Zr concentrations, indicating fractional crystallization of amphibole with the observed accessory mineral assemblage such as Fe-Ti oxides, titanite, zircon and apatite. On the other hand, most of the porphyries exhibit relatively high Al2O3, Ba and Sr concentrations and pronounced positive Eu anomalies, excluding significant plagioclase fractionation due to suppression of the high water content in the magmas. The presence of the contemporary amphibole cumulates regionally exposed in the study area strongly support significant amphibole fractionation during the formation of the Mujicun porphyries. Thus, fractionation of a water-saturated magma is proposed as a

  1. Landscape, Mountain Worship and Astronomy in Socaire

    NASA Astrophysics Data System (ADS)

    Moyano, Ricardo

    The spatiotemporal analysis of mountain worship in the indigenous community of Socaire, Atacama, northern Chile, relates to cultural, geographical, climatic, psychological, and astronomical information gathered from ethno archaeological studies. We identify a system of offerings to the mountains that incorporates concepts such as ceque (straight line), mayllku (mountain lord or ancestor), and pacha (space and time). Here, the mountains on the visible horizon (Tumisa, Lausa, Chiliques, Ipira, and Miñiques) feature as the fingers on the left hand (PAH Triad). This structure regulates annual activities and rituals and sets the basis for the Socaireños' worldview raised on a humanized landscape.

  2. Earthshots: Satellite images of environmental change – Elburz Mountains, Iran

    USGS Publications Warehouse

    U.S. Geological Survey

    2013-01-01

    The Elburz Mountains run parallel to the southern coast of the Caspian Sea, and these mountains act as a barrier to rain clouds moving southward; as the clouds rise in altitude to cross the mountains they drop their moisture. This abundant rainfall supports a heavy rainforest (the bright red area) on the northern slopes. The valley to the south receives little precipitation because of this rain-shadow effect of the mountains.

  3. Paleomagnetism of the Mesozoic Asik Mountain mafic complex in northern Alaska: implications for the tectonic history of the Arctic composite terrane

    USGS Publications Warehouse

    Lewchuk, Michael T.; Foucher, Jamie; Elmore, R.D.

    2004-01-01

    At least three mutually exclusive hypotheses exist for the origin of the Arctic composite terrane and its Mesozoic location relative to the stable craton of North America. The most widely accepted hypothesis calls for counterclockwise rotation of the Arctic composite terrane as it rifted from the Arctic Archipelago. A second hypothesis calls for no relative movement, and a third places the Arctic composite terrane on the Kula plate as a part of a separate ribbon-shaped microcontinent. All three hypotheses predict unique positions for the Arctic composite terrane with respect to rotation and translation since the middle of the Mesozoic. Paleomagnetic and susceptibility studies were conducted on rocks from 15 sites in the ~160 Ma (K-Ar cooling age) Asik Mountain mafic to ultramafic complex in the western part of the Arctic composite terrane. Coherent data from 11 sites yielded a direction of dec = 255.1°, inc = 82.1° κ = 19.3, α95 = 9.6°, α63 = 5.6°. Contact and fold tests were not possible but the direction differs distinctly from the modern magnetic direction. The anisotropy of magnetic susceptibility revealed a well-developed oblate fabric of variable orientation. The orientation of the fabric was not related to the regional stress regime, so we conclude that the rocks were not deformed and metamorphosed during thrusting, and thus the magnetic remanence direction obtained is most likely primary. The direction yields a pole position at long = 166.8°E, lat = 59.8°N, A95 = 18.4°, A63 = 10.7° that is discordant to the expected 160 Ma reference direction for North America. Counterclockwise rotation of the Arctic composite terrane would yield a perfect fit to the 160 Ma reference pole with an allowance for up to 5° of northward translation. This result, combined with previous paleomagnetic data, makes a convincing argument that the Arctic composite terrane has not remained fixed in its current orientation with respect to North America. However, the data are

  4. Processes affecting the response of sulfate concentrations to clearcutting in a northern hardwood forest, Catskill Mountains, New York, U.S.A.

    USGS Publications Warehouse

    Welsch, D.L.; Burns, Douglas A.; Murdoch, Peter S.

    2004-01-01

    The effects of disturbance on the biogeochemical processes that affect the sulfur (S) cycle in forested ecosystems are important, but have been studied in only a few locations. In this investigation, the mechanisms that caused large decreases in stream SO42- concentrations after clearcutting a small forested catchment in the Catskill Mountains of southeastern New York in 1997 were identified through an examination of pH and SO42- concentrations in soil solutions, bulk deposition of SO42- in throughfall collectors, adsorbed SO 42- concentrations in buried soil bags, and spatial variations in SO42- concentrations in shallow groundwater. The load of SO42- -S in stream water during the first 2 years after clearcutting was about 2 kg ha-1.year-1 less than the background value of 8-10 kg ha-1 year-1. The 10 and 19% decrease in net throughfall flux of SO42- -S during the 2nd and 3rd year after the clearcut, respectively, reflects reduced dry deposition of S after removal of the canopy, but this decrease accounts for 0 and 43%, respectively, of the decrease in SO42- load in streamflow for these 2 years. The pH of B-horizon soil water decreased from 4.5 to 4.0 within 8 months after the clearcut, and SO42- concentrations decreased from 45 ??mol L-1 to less than 20 ??mol L-1 during this time. A strong correlation between SO 42- concentrations and pH values (r2=0.71, p<0.01) in B-horizon soil water during the post-harvest period (1997-1999) reflects increased SO42- adsorption in response to soil acidification. Sulfate concentrations in groundwater from 21 spatially distributed wells were inversely related to a topographic index that served as a surrogate for soil wetness; thus, providing additional evidence that SO 42- adsorption was the dominant cause of the decreased SO42- concentrations in the stream after clearcutting. These results are consistent with those from a 1985 whole-tree harvest at the Hubbard Brook Experimental Forest in New Hampshire in which increased SO 42

  5. Effects of flow releases on macroinvertebrate assemblages in the Indian and Hudson Rivers in the Adirondack Mountains of Northern New York

    USGS Publications Warehouse

    Baldigo, Barry P.; Smith, A.J.

    2011-01-01

    The effects of flow releases (daily during spring and four times weekly during summer) from a small impoundment on macroinvertebrate assemblages in the lower Indian River and upper Hudson River of northern New York were assessed during the summers of 2005 and 2006. Community indices, feeding guilds, dominant species and Bray—Curtis similarities at three sites on the Indian River, below a regulated impoundment, were compared with those at four control sites on the Cedar River, below a run-of-the-river impoundment of comparable size. The same indices at four less-likely affected sites on the Hudson River, below the mouth of the Indian River, were compared with those at an upstream control site on the Hudson River. Results show that the function and apparent health of macroinvertebrate communities were generally unaffected by atypical flow regimes and/or altered water quality at study reaches downstream from both dams in the Indian, Cedar and Hudson Rivers. The lentic nature of releases from both impoundments, however, produced significant changes in the structure of assemblages at Indian and Cedar River sites immediately downstream from both dams, moderate effects at two Indian River sites 2.4 and 4.0 km downstream from its dam, little or no effect at three Cedar River sites 7.2-34.2 km downstream from its dam, and no effect at any Hudson River site. Bray—Curtis similarities indicate that assemblages did not differ significantly among sites within similar impact categories. The paucity of scrapers at all Indian River sites, and the predominance of filter-feeding Simulium gouldingi and Pisidium compressum immediately below Abanakee dam, show that only minor differences in dominant species and trophic structure of macroinvertebrate communities occurred at affected sites in the Indian River compared to the Cedar River. Thus, flow releases had only a small, localized effect on macroinvertebrate communities in the Indian River.

  6. New morpho-stratigraphic constraints for the evolution of the alluvial fan system along the northern slopes of the Taburno-Camposauro Mountains (Calore River basin, Southern Italy)

    NASA Astrophysics Data System (ADS)

    Leone, Natalia; Amato, Vincenzo; Aucelli, Pietro P. C.; Cesarano, Massimo; Filocamo, Francesca; Petrosino, Paola; Rosskopf, Carmen M.; Valente, Ettore; Giralt, Santiago; Casciello, Emilio

    2016-04-01

    The Lower Calore River Valley is a morphostructural depression located in the inner sector of the Campanian Apennine, between the Taburno-Camposauro and the Matese carbonate massifs. The river is the main left tributary of the Volturno River, it has a meandering channel partially structural-controlled. Numerous morphotectonic clues and historical seismicity data suggest that this part of the Apennine chain was particularly active during the late-Quaternary. In detail, the valley is E-W oriented and presents an asymmetry of the opposed valley slopes. The left side, corresponding to the northern flank of the Camposauro massif, is characterized by a steep slope (70°-35°), partially controlled by a ~E-W oriented fault system, and by a wide less-inclined piedmont aggradation zone. The latter started growing since middle Pleistocene, with the deposition of alluvial fans and slope deposits over the well cemented early Pleistocene breccias of Laiano Synthem. The alluvial fan deposition has been active until present giving rise to three main generations of alluvial fans. The right side of the valley, instead, is characterized by seven orders of fluvial terraces, both of erosional and depositional origin. The quaternary morpho-stratigraphic evolution of alluvial fans and fluvial terraces has been strongly conditioned by the interaction of tectonic phases and climatic variations. A detailed geomorphological study (1:5.000 in scale) was carried out with the aim to map the main depositional and erosional fluvial landforms and to identify the main tectonic lineaments of the area. A detailed field survey allowed to better define the stratigraphic and paleoenvironmental context in which the alluvial deposits developed and also to find chrono-stratigraphic markers. Tephra-stratigraphic analyses were performed on pyroclastic deposits interbedded into the alluvial fan and fluvial successions. At the moment the age of the first generation of alluvial fans is still under

  7. Stone Mountain

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This color image taken by the panoramic camera onboard the Mars Exploration Rover Opportunity shows the part of the rock outcrop dubbed Stone Mountain at Meridiani Planum, Mars. Scientists are examining Stone Mountain with the instruments on the rover's instrument deployment device, or 'arm,' in search of clues about the composition of the rock outcrop. [figure removed for brevity, see original site] A Patch of Stone (Figure credit: NASA/JPL/Cornell/USGS)

    The colorless square in this color image of the martian rock formation called Stone Mountain is one portion of the rock being analyzed with tools on the Mars Exploration Rover Opportunity's instrument deployment device, or 'arm.' The square area is approximately 3 centimeters (1.2 inches) across. Stone Mountain is located within the rock outcrop on Meridiani Planum, Mars. The image was taken by the rover's panoramic camera.

  8. Mountain research

    NASA Astrophysics Data System (ADS)

    The newly incorporated International Mountain Society (IMS) will in May begin publication of an interdisciplinary scientific journal, Mountain Research and Development. The quarterly will be copublished with the United National University; additional support will come from UNESCO.A primary objective of IMS is to ‘help solve mountain land-use problems by developing a foundation of scientific and technical knowledge on which to base management decisions,’ according to Jack D. Ives, president of the Boulder-based organization. ‘The Society is strongly committed to the belief that a rational worldwide approach to mountain problems must involve a wide range of disciplines in the natural and human sciences, medicine, architecture, engineering, and technology.’

  9. White Mountain Wilderness, New Mexico

    SciTech Connect

    Segerstrom, K.; Stotelmeyer, R.B.

    1984-01-01

    On the basis of a mineral survey made during 1971-1973, the White Mountain Wilderness, which constitutes much of the western and northern White Mountains, New Mexico, is appraised to have six areas of probable mineral potential for base and precious metals. In mineral deposits exist in the wilderness, the potential is for small deposits of base and precious metals in veins and breccia pipes or, more significantly, the possibility for large low-grade disseminated porphyry-type molybdenum deposits. There is little promise for the occurrence of geothermal energy resources in the area.

  10. Caucasus Mountains

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Often regarded as the southeastern border of Europe, the Caucasus Mountains can be seen here stretching from the Black Sea (left) to the Caspian Sea (right). The mountain range spans 700 miles (1125 km), crossing the countries of Russian Federation, Georgia, and Azerbaijan from left to right respectively. With a snowline of approximately 11,000 feet and peaks such as Mt. Elbrus, that reach 15,000 feet, much of the snow visible in this image is present year round. Also visible in this image are apparent phytoplankton blooms in the Caspian Sea, marked by blue-green swirls.

  11. Spatial distribution and temporal variation of ecological capital and their relation to climate change and the changes of land use and land cover on the northern slope of the Tianshan Mountain, China

    NASA Astrophysics Data System (ADS)

    Zhang, Qing; Chen, Xiuwan; Gao, Wei; Zhang, Xianfeng; Zhou, Kefa; Wang, Xinli

    2007-09-01

    Ecological capital of an ecosystem is the total value of the direct biological products in the system and the value of ecological service. The assessment of ecological capital is a new research area emerged from the challenge in the interdisciplinary research of ecology and social development. It is fundamental to establish a green national economy accounting system. Scientific evaluation of ecological capital is helpful for considering ecological cost in making the decision for economic development, and it is demanded for sustainable development. In this study, a quantitative assessment model of ecological property has been developed based on the analysis of per unit yield in the conventional ecology together with the utilization of remote sensing data from the Landsat TM, CBERS, MODIS, and NOAA database, land use and land cover data, and field measurements. The study area covers Changji Autonomous District, Xinjiang, China on the northern slope of Tianshan Mountain that is located in a typical arid area. Dynamic monitoring of ecological capital was performed using remote sensing techniques. Spatial distribution and temporal variation of ecological properties were characterized. The effects of land cover and land use as well as climate change on those variation and distribution were analyzed. The results show a significant increase in the ecological capital during 1990-2003. The spatial distribution of ecological properties is characterized by a negative gradient from higher altitudes to lower altitudes (plains) and from oases to deserts, which is consistent with the zonal distribution of vegetation in arid areas. Due to global warming, the climate in Xinjiang has been changed into a warmer and wetter environment during the last 50 years, which improves the plant growing conditions in the alpine regions, piedmont hilly regions, and the oases. On the other hand, the natural environment in the arid and semiarid regions in northwest China becomes more severe, and the

  12. Magnificent Mountains

    ERIC Educational Resources Information Center

    Anderson, Heather

    2004-01-01

    One way to increase awareness of endangered national heritage is to teach youth the importance of the land through the study of selected works of art. This article describes a lesson, in which students will study the work of Thomas Moran and create a mountain range collage. A short biography of Thomas Moran is included.

  13. EVIDENCE OF AIRBORNE CONTAMINATION OF WESTERN NORTH AMERICAN MOUNTAIN ECOSYSTEMS

    EPA Science Inventory

    There is emerging evidence that mountain ecosystems in the western USA are receiving deposition of persistent bioaccumulative toxicants with origins in North America and elsewhere in the Northern Hemisphere. The toxic materials include metals and organic compounds. Of particula...

  14. [Mountain sickness].

    PubMed

    Bultas, Jan

    2015-01-01

    Mountaineering brings many health risks, one of which is mountain sickness. Its mildest form - acute mountain sickness - is mainly characterized by subjective symptoms (headache, loss of appetite, insomnia, weakness, nausea and rarely also vomiting). Advanced and life-threatening forms are characterized by tissue edema - cerebral or pulmonary high altitude edema. The common denominator of these acute forms is the low oxygen tension leading to hypoxemia and tissue ischemia. Sum of maladaptive or adaptive processes can modify the clinical picture. Underlying mechanisms of the chronic forms of pulmonary disease are the adaptation processes - pulmonary hypertension and polycythemia leading to heart failure.The only causal therapeutic intervention is to restore adequate oxygen tension, descend to lower altitudes or oxygen therapy. Pharmacotherapy has only a supportive effect. The prophylaxis includes stimulation of the respiratory center by carbonic anhydrase inhibitors (acetazolamide) antiedematous treatment with glucocorticoids (dexamethasone), increase lymphatic drainage of the lungs and brain by β2-agonists (salmeterol) or mitigation of pulmonary hypertension by calcium channel blockers or phosphodiesterase-5 inhibitors (sildenafil or tadalafil). PMID:26750624

  15. Seasonal Distributions of Mountain Torques during FGGE.

    NASA Astrophysics Data System (ADS)

    Wei, Ming-Ying; Schaack, Todd K.

    1984-10-01

    Based on surface pressure and terrain height analyses from the National Meteorological Center, mountain torques are calculated for January, April, July and October 1979 during the First GARP Global Experiment. The zonally integrated mountain torques are generally in good agreement with previous studies. For all four months, positive torque exists in the tropical latitudes as well as in the polar and subtropical latitudes of the Northern Hemisphere; negative torque exists in northern middle latitudes and most of the Southern Hemisphere. An exception occurs in July when the mountain torque is negative between 5 and 25°N and positive in the Southern Hemisphere subtropics. Over latitudes where large terrain variation exists such as near 20°S due to the Andes, the estimate obtained in this study is larger in magnitude than that from previous work. The difference is due to the differences in both grid resolution and the particular atmospheric data and topography selected.The meridional profiles of individual continental mountain torques are examined to illustrate geographical contributions to the net zonal torque. The positive mountain torque in northern high latitudes is due mainly to North America and Greenland. Both North America and Eurasia contribute to the sink of angular momentum in northern middle latitudes and the source in the subtropical latitudes. The negative torque between 5 and 25°N in July is due to the influence of the Indian monsoon trough on Arabia and Africa. The negative mountain torque over South America dominates the positive torque over Africa and Australia in the Southern Hemisphere in January and October.Although the monthly averaged zonally integrated mountain torque assumes lesser importance when compared to the frictional torque, regional mountain torque at the synoptic time scale is quite large and can have considerable influence on the large scale circulation. Hemispheric torques are in qualitative agreement with previous work. Due to

  16. Preliminary results of chronostratigraphic field work, OSL-dating and morphogenetic reconstruction of an alluvial apron at Alborz southern foothill, Damghan basin, Iran

    NASA Astrophysics Data System (ADS)

    Büdel, Christian; Fuchs, Markus; Majid Padashi, Seyed; Baumhauer, Roland

    2014-05-01

    Here we present preliminary results of a chronostratigraphic study of an alluvial fan in the Damghan Basin, northern Iran. The basin sediments date back to the Mio- and Pliocene and therefore represent the starting point of alluvial fan aggradation. Today, the still active alluvial fans prograde from the Albors Mountain ranges and sit on the older sediment bodies. In this study, our focus is on the late Pleistocene to Holocene alluvial fan sedimentation history. The upper stratigraphy of the alluvial fans and intercalated lake deposits is characterized by six individual layers of gravels and fines, representing six different stratigraphic units. These units are described and classified by detailed geomorphological and stratigraphic mapping. To establish an alluvial fan chronology, six profiles were sampled for OSL dating. As expected, due to the high-energy transport system of alluvial fan aggradation in semi-desert environments, OSL dating of these sediments is challenging due to the problem of insufficient bleaching. Consequently, most of the samples are interpreted as maximum ages. However, the measurements show a consistent internal age structure and the overall OSL-based chronology is in agreement with the age model derived from our geomorphological analysis. As a first interpretation, based on surveyed geomorphological features and chronological analysis, we could identify seven morphodynamic phases, leading to a genetic model of alluvial fan aggradation. The oldest Pleistocene age estimate is derived from a former lake terrace. The following ages represent ongoing lake sediment deposition and the development of a proximal and mid-fan gravel cover. After the youngest lake deposits were accumulated within the Holocene, the lake starts to retreat and small alluvial fans are filling up the former lake bottom. This last sedimentation phase can be divided in at least two sub-phases, probably coupled to a lateral shifting of the active depositional lobe and to the

  17. Bryozoa of the Murdock Mountain formation (Wordian, Permian), Leach Mountains, northeastern Nevada

    USGS Publications Warehouse

    Gilmour, E.H.; McColloch, M.E.; Wardlaw, B.R.

    1997-01-01

    A thin limestone tongue in the upper part of the Murdock Mountain Formation of northeastern Nevada contains abundant bryozoans of earliest Wordian age. This bryozoan fauna is close to the Kungurian-Kazanian boundary in Russia. These bryozoans are younger than those found in the Kaibab Formation of southern Nevada and slightly older than those in the Gerster Limestone of northern Nevada. This limestone tongue, herein referred to as the Stenodiscus beds, lies below the Thamnosia beds described by Wardlaw in the Murdock Mountain section of the Leach Mountains. This bryozoan-rich limestone tongue serves as a marker unit for mapping the Murdock Formation in the Leach Mountains. Nine new species of bryozoans occur in the Stenodiscus beds of the Murdock Mountain Formation: Hinganella felderi, Neoeridotrypella schilti, Stenopora parvaexozona, Stenodiscus murdockensis, Dyscritella acanthostylia, Pseudobatostomella irregularis. Streblotrypa (Streblotrypa) elongata, Morozoviella praecurriensis, and Thamniscus erraticus, Hinganella felderi, Neoeridotrypella schilti, Dyscritella acanthostylia, and Streblotrypa (Streblotrypa) elongata are very similar to species described from Russia.

  18. 2. EAGLE MOUNTAIN SWITCHYARD. EAGLE MOUNTAIN PUMP PLANT CAN BE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. EAGLE MOUNTAIN SWITCHYARD. EAGLE MOUNTAIN PUMP PLANT CAN BE SEEN THROUGH SWITCHYARD IN BACKGROUND. 165MM LENS. - Eagle Mountain Pump Plant, Ten miles north of Route 10, southeast of Eagle Mountain, Eagle Mountain, Riverside County, CA

  19. Late glacial aridity in southern Rocky Mountains

    SciTech Connect

    Davis, O.K.; Pitblado, B.L.

    1995-09-01

    While the slopes of the present-day Colorado Rocky Mountains are characterized by large stands of subalpine and montane conifers, the Rockies of the late glacial looked dramatically different. Specifically, pollen records suggest that during the late glacial, Artemisia and Gramineae predominated throughout the mountains of Colorado. At some point between 11,000 and 10,000 B.P., however, both Artemisia and grasses underwent a dramatic decline, which can be identified in virtually every pollen diagram produced for Colorado mountain sites, including Como Lake (Sangre de Cristo Mountains), Copley Lake and Splains; Gulch (near Crested Butte), Molas Lake (San Juan Mountains), and Redrock Lake (Boulder County). Moreover, the same pattern seems to hold for pollen spectra derived for areas adjacent to Colorado, including at sites in the Chuska Mountains of New Mexico and in eastern Wyoming. The implications of this consistent finding are compelling. The closest modem analogues to the Artemisia- and Gramineae-dominated late-glacial Colorado Rockies are found in the relatively arid northern Great Basin, which suggests that annual precipitation was much lower in the late-glacial southern Rocky Mountains than it was throughout the Holocene.

  20. Conodont color alteration (CAI) as an aid to structural interpretation in the Black Pine Mountains, Idaho

    USGS Publications Warehouse

    Smith, Fred J., Jr.; Wardlaw, Bruce R.

    2012-01-01

    The Black Pine Mountains, southeastern Cassia County, Idaho, consist of southern and northern blocks separated by a northeast-trending, high-angle fault. Differences in conodont color alteration values distinguish the two blocks. The southern block has significantly higher organic maturation levels than the northern block and is interpreted to have been thrust northeastward adjacent to the northern block.

  1. Strong Genetic Differentiation of Submerged Plant Populations across Mountain Ranges: Evidence from Potamogeton pectinatus in Iran

    PubMed Central

    Abbasi, Shabnam; Afsharzadeh, Saeed; Saeidi, Hojjatollah; Triest, Ludwig

    2016-01-01

    Biogeographic barriers for freshwater biota can be effective at various spatial scales. At the largest spatial scale, freshwater organisms can become genetically isolated by their high mountain ranges, vast deserts, and inability to cross oceans. Isolation by distance of aquatic plants is expected to be stronger across than alongside mountain ridges whereas the heterogeneity of habitats among populations and temporary droughts may influence connectivity and hamper dispersal. Suitable aquatic plant habitats became reduced, even for the widespread submerged Potamogeton pectinatus L. (also named Stuckenia pectinata) giving structure to various aquatic habitats. We compared the level of genetic diversity in a heterogeneous series of aquatic habitats across Iran and tested their differentiation over distances and across mountain ranges (Alborz and Zagros) and desert zones (Kavir), with values obtained from temperate region populations. The diversity of aquatic ecosystems across and along large geographic barriers provided a unique ecological situation within Iran. P. pectinatus were considered from thirty-six sites across Iran at direct flight distances ranging from 20 to 1,200 km. Nine microsatellite loci revealed a very high number of alleles over all sites. A PCoA, NJT clustering and STRUCTURE analysis revealed a separate grouping of individuals of southeastern Iranian sites and was confirmed by their different nuclear ITS and cpDNA haplotypes thereby indicating an evolutionary significant unit (ESU). At the level of populations, a positive correlation between allelic differentiation Dest with geographic distance was found. Individual-based STRUCTURE analysis over 36 sites showed 7 genetic clusters. FST and RST values for ten populations reached 0.343 and 0.521, respectively thereby indicating that allele length differences are more important and contain evolutionary information. Overall, higher levels of diversity and a stronger differentiation was revealed among

  2. Strong Genetic Differentiation of Submerged Plant Populations across Mountain Ranges: Evidence from Potamogeton pectinatus in Iran.

    PubMed

    Abbasi, Shabnam; Afsharzadeh, Saeed; Saeidi, Hojjatollah; Triest, Ludwig

    2016-01-01

    Biogeographic barriers for freshwater biota can be effective at various spatial scales. At the largest spatial scale, freshwater organisms can become genetically isolated by their high mountain ranges, vast deserts, and inability to cross oceans. Isolation by distance of aquatic plants is expected to be stronger across than alongside mountain ridges whereas the heterogeneity of habitats among populations and temporary droughts may influence connectivity and hamper dispersal. Suitable aquatic plant habitats became reduced, even for the widespread submerged Potamogeton pectinatus L. (also named Stuckenia pectinata) giving structure to various aquatic habitats. We compared the level of genetic diversity in a heterogeneous series of aquatic habitats across Iran and tested their differentiation over distances and across mountain ranges (Alborz and Zagros) and desert zones (Kavir), with values obtained from temperate region populations. The diversity of aquatic ecosystems across and along large geographic barriers provided a unique ecological situation within Iran. P. pectinatus were considered from thirty-six sites across Iran at direct flight distances ranging from 20 to 1,200 km. Nine microsatellite loci revealed a very high number of alleles over all sites. A PCoA, NJT clustering and STRUCTURE analysis revealed a separate grouping of individuals of southeastern Iranian sites and was confirmed by their different nuclear ITS and cpDNA haplotypes thereby indicating an evolutionary significant unit (ESU). At the level of populations, a positive correlation between allelic differentiation Dest with geographic distance was found. Individual-based STRUCTURE analysis over 36 sites showed 7 genetic clusters. FST and RST values for ten populations reached 0.343 and 0.521, respectively thereby indicating that allele length differences are more important and contain evolutionary information. Overall, higher levels of diversity and a stronger differentiation was revealed among

  3. The Knight and the King: two new species of giant bent-toed gecko (Cyrtodactylus, Gekkonidae, Squamata) from northern New Guinea, with comments on endemism in the North Papuan Mountains

    PubMed Central

    Oliver, Paul M.; Richards, Stephen J.; Mumpuni; Rösler, Herbert

    2016-01-01

    Abstract The diverse biota of New Guinea includes many nominally widespread species that actually comprise multiple deeply divergent lineages with more localised histories of evolution. Here we investigate the systematics of the very large geckos of the Cyrtodactylus novaeguineae complex using molecular and morphological data. These data reveal two widespread and divergent lineages that can be distinguished from each other, and from type material of Cyrtodactylus novaeguineae, by aspects of size, build, coloration and male scalation. On the basis of these differences we describe two new species. Both have wide distributions that overlap extensively in the foothill forests of the North Papuan Mountains, however one is seemingly restricted to hill and lower montane forests on the ranges themselves, while the other is more widespread throughout the surrounding lowlands. The taxon endemic to the North Papuan Mountains is related to an apparently lowland form currently known only from Waigeo and Batanta Island far to the west – hinting at a history on island arcs that accreted to form the North Papuan Mountains. PMID:27006624

  4. The Knight and the King: two new species of giant bent-toed gecko (Cyrtodactylus, Gekkonidae, Squamata) from northern New Guinea, with comments on endemism in the North Papuan Mountains.

    PubMed

    Oliver, Paul M; Richards, Stephen J; Mumpuni; Rösler, Herbert

    2016-01-01

    The diverse biota of New Guinea includes many nominally widespread species that actually comprise multiple deeply divergent lineages with more localised histories of evolution. Here we investigate the systematics of the very large geckos of the Cyrtodactylus novaeguineae complex using molecular and morphological data. These data reveal two widespread and divergent lineages that can be distinguished from each other, and from type material of Cyrtodactylus novaeguineae, by aspects of size, build, coloration and male scalation. On the basis of these differences we describe two new species. Both have wide distributions that overlap extensively in the foothill forests of the North Papuan Mountains, however one is seemingly restricted to hill and lower montane forests on the ranges themselves, while the other is more widespread throughout the surrounding lowlands. The taxon endemic to the North Papuan Mountains is related to an apparently lowland form currently known only from Waigeo and Batanta Island far to the west - hinting at a history on island arcs that accreted to form the North Papuan Mountains. PMID:27006624

  5. Petrogenesis of Tarom high-potassic granitoids in the Alborz-Azarbaijan belt, Iran: Geochemical, U-Pb zircon and Sr-Nd-Pb isotopic constraints

    NASA Astrophysics Data System (ADS)

    Nabatian, Ghasem; Ghaderi, Majid; Neubauer, Franz; Honarmand, Maryam; Liu, Xiaoming; Dong, Yunpeng; Jiang, Shao-Yong; von Quadt, Albrecht; Bernroider, Manfred

    2014-01-01

    Large-scale Upper Eocene plutons in the Western Alborz-Azarbaijan orogenic belt mostly show calc-alkaline and I-type geochemical features contrasted by the Tarom complex with its high-potassic to shoshonitic affinity. The pluton was emplaced in the Tarom subzone of the orogenic belt and its laser ICP-MS zircon U-Pb age of 41 Ma is interpreted as the age of magma crystallization. The Tarom complex is composed of quartz monzodiorite, quartz-monzonite and monzogranite, the SiO2 contents range from 57 to 70 wt.%, the K2O + Na2O content is high (5.0-8.9 wt.%) and K2O/Na2O ratio ranges from 0.4 to 1.9. All the investigated rocks are enriched in light rare earth elements (LREEs), large ion lithophile elements (LILEs) and depleted in high field strength elements (HFSEs), and bear a weak Eu anomaly (Eu/Eu* = 0.46 to 1.38) in chondrite-normalized trace element patterns. The samples display some variety in initial Sr and Nd isotopic compositions, marked with low ISr = 0.704-0.705 and ɛNd (40 Ma) = - 4.2 to + 3.4 (- 5.7 for an enclave) values. The Pb isotopic ratios are (206Pb/204Pb) = 18.52-18.86, (207Pb/204Pb) = 15.57-15.72 and (208Pb/204Pb) = 38.47-39.08. Comparison with experimental studies, together with mantle-like isotopic ratios and comparisons of REE patterns, points to an origin of chemically enriched lithospheric mantle source for the Tarom plutonic complex. Partial melting process involving different partial melting degrees affecting heterogeneously metasomatized mantle is a process that seems likely to have occurred in the studied complex as the major differentiation process. The Tarom monzonitic plutons are considered to be post-orogenic intrusions that were emplaced in an environment of lithospheric extension, causing asthenospheric upwelling. Asthenospheric upwelling induced a thermal anomaly which caused partial melting of metasomatized subcontinental lithospheric mantle in the Tarom area.

  6. Zircon U-Pb ages, geochemical and Sr-Nd-Pb-Hf isotopic constraints on petrogenesis of the Tarom-Olya pluton, Alborz magmatic belt, NW Iran

    NASA Astrophysics Data System (ADS)

    Nabatian, Ghasem; Jiang, Shao-Yong; Honarmand, Maryam; Neubauer, Franz

    2016-02-01

    A petrological, geochemical and Sr-Nd-Pb isotopic study was carried out on the Tarom-Olya pluton, Iran, in the central part of the Alpine-Himalayan orogenic belt. The pluton is composed of diorite, monzonite, quartz-monzonite and monzogranite, which form part of the Western Alborz magmatic belt. LA-ICP-MS analyses of zircons yield ages from 35.7 ± 0.8 Ma to 37.7 ± 0.5 Ma, interpreted as the ages of crystallization of magmas. Rocks from the pluton have SiO2 contents ranging from 57.0 to 69.9 wt.%, high K2O + Na2O (5.5 to 10.3 wt.%) and K2O/Na2O ratio of 0.9 to 2.0. Geochemical discrimination criteria show I-type and shoshonitic features for the studied rocks. All investigated rocks are enriched in light rare earth elements (LREEs), large ion lithophile elements (LILEs), depleted in high-field strength elements (HFSEs), and show weak or insignificant Eu anomalies (Eu/Eu* = 0.57-1.02) in chondrite-normalized trace element patterns. The Tarom-Olya pluton samples also show depletions in Nb, Ta and Ti typical of subduction-related arc magmatic signatures. The samples have relatively low ISr (0.7047-0.7051) and positive εNd(36 Ma) (+ 0.39 to + 2.10) values. The Pb isotopic ratios show a (206Pb/204Pb)i ratio of 18.49-18.67, (207Pb/204Pb)i ratio of 15.58-15.61 and (208Pb/204Pb)i ratio of 38.33-38.77. The εHf(t) values of the Tarom-Olya pluton zircons vary from - 5.9 to + 8.4, with a peak at + 2 to + 4. The depleted mantle Hf model ages for the Tarom-Olya samples are close to 600 Ma. These isotope evidences indicate contribution of juvenile sources in petrogenesis of the Tarom-Olya pluton. Geochemical and isotopic data suggest that the parental magma of the Tarom-Olya pluton was mainly derived from a sub-continental lithospheric mantle source, which was metasomatized by fluids and melts from the subducted Neotethyan slab with a minor crustal contribution. Subsequent hot asthenospheric upwelling and lithospheric extension caused decompression melting in the final stage of

  7. Looking at the roots of the highest mountains: the lithospheric structure of the Himalaya-Tibet and the Zagros orogens. Results from a geophysical-petrological study

    NASA Astrophysics Data System (ADS)

    Tunini, L.; Jimenez-Munt, I.; Fernandez, M.; Villasenor, A.; Afonso, J. C.; Verges, J.

    2013-12-01

    The Himalaya-Tibet and Zagros orogens are the two most prominent mountain belts built by continental collision. They are part of a huge belt of Cenozoic age which runs from the Pyrenees to Burma. In its central sector, the collision with the southern margin of the Eurasian plate has resulted not only in the building of mountain ranges over the north-eastern edges of the Arabian and Indian plates but also in widespread deformation 1000-3000 km from the suture zones. Zagros and Himalaya-Tibet orogens share many geodynamic processes but at different rates, amount of convergence and stage of development. The study of their present-day structures provides new insights into their quasi coeval collisional event pointing out differences and similarities in the mountain building processes. We present 2D crust and upper mantle cross-sections down to 400 km depth, along four SW-NE trending profiles. Two profiles cross the Zagros Mountains, running from the Mesopotamian Foreland Basin up to the Alborz and Central Iran. Two other profiles run through the Himalaya-Tibetan orogen: the western transect crosses the western Himalaya, Tarim Basin, Tian Shan Mountains and Junggar Basin; the eastern transect runs from the Indian shield to the Beishan Basin, crossing the eastern Himalaya, Tibetan Plateau, Qaidam Basin and Qilian Mountains. We apply the LitMod-2D code which integrates potential fields (gravity and geoid), isostasy (elevation) and thermal (heat flow and temperature distribution) equations, and mantle petrology. The resulting crust and upper mantle structure is constrained by available data on elevation, Bouguer anomaly, geoid height, surface heat flow and seismic data including P- and S-wave tomography models. Our results show distinct deformation patterns between the crust and the lithospheric mantle beneath the Zagros and Himalaya-Tibetan orogens, indicating a strong strain partitioning in both areas. At crustal level, we found a thickening beneath the Zagros and the

  8. Fault kinematics and stress fields in the Rwenzori Mountains, Uganda

    NASA Astrophysics Data System (ADS)

    Sachau, Till; Koehn, Daniel; Stamps, D. Sarah; Lindenfeld, Michael

    2015-03-01

    The Rwenzori Mountains in western Uganda form an active rift-transfer zone in the western branch of the East African Rift System. Here we quantify local stress fields in high resolution from field observations of fault structures to shed light on the complex, polyphase tectonics expected in transfer zones. We apply the multiple inverse method, which is optimized for heterogeneous fault-slip data, to the northern and central Rwenzori Mountains. Observations from the northern Rwenzori Mountains show larger heterogeneity than data from the central Rwenzori, including unexpected compressional features; thus the local stress field indicates polyphase transpressional tectonics. We suggest that transpression here is linked to rotational and translational movements of the neighboring Victoria block relative to the Rwenzori block that includes strong overprinting relationships. Stress inversions of data from the central Rwenzori Mountains indicate two distinct local stress fields. These results suggest that the Rwenzori block consists of smaller blocks.

  9. Rocky Mountain spotted fever

    MedlinePlus

    Rocky Mountain spotted fever is a disease caused by a type of bacteria carried by ticks. ... Rocky Mountain spotted fever is caused by the bacteria Rickettsia rickettsii (R. Rickettsii) , which is carried by ticks. The ...

  10. Acute mountain sickness

    MedlinePlus

    High altitude cerebral edema; Altitude anoxia; Altitude sickness; Mountain sickness; High altitude pulmonary edema ... Acute mountain sickness is caused by reduced air pressure and lower oxygen levels at high altitudes. The faster you ...

  11. Rocky Mountain spotted fever

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/000654.htm Rocky Mountain spotted fever To use the sharing features on this page, please enable JavaScript. Rocky Mountain spotted fever is a disease caused by a ...

  12. Anti-Atlas Mountains, Morocco

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The Anti-Atlas Mountains of northern Africa and the nearby Atlas mountains were created by the prolonged collision of the African and Eurasian tectonic plates, beginning about 80 million years ago. Massive sandstone and limestone layers have been crumpled and uplifted more than 4,000 meters in the High Atlas and to lower elevations in the Anti-Atlas. Between more continuous major fold structures, such as the Jbel Ouarkziz in the southwestern Anti-Atlas, tighter secondary folds (arrow) have developed. Earlier, the supercontinent of Pangea rifted apart to form precursors to the Mediterranean and the Atlantic Ocean (Beauchamp and others, 1996). In those seas sands, clays, limey sediments, and evaporite layers (gypsum, rock salt) were deposited. Later, during the mountain-building plate collision, the gypsum layers flowed under the pressure and provided a slippery surface on which overlying rigid rocks could glide (Burkhard, 2001). The broad, open style of folds seen in this view is common where evaporites are involved in the deformation. Other examples can be found in the Southern Zagros of Iran and the Sierra Madre Oriental of Mexico. Information Sources: Beauchamp, W., Barazangi, M., Demnati, A., and El Alji, M., 1996, Intracontinental rifting and inversion: Missour Basin and Atlas Mountains, Morocco: Tulsa, American Association of Petroleum Geologists Bulletin, v. 80, No. 9, p. 1459-1482. Burkhard, Martin, 2001, Tectonics of the Anti-Atlas of Morocco -- Thin-skin/thick-skin relationships in an atypical foreland fold belt. University of Neuchatel, Switzerland: http://www-geol.unine.ch/Structural/Antiatlas.html (accessed 1/29/02). STS108-711-25 was taken in December, 2001 by the crew of Space Shuttle mission 108 using a Hasselblad camera with 250-mm lens. The image is provided by the Earth Sciences and Image Analysis Laboratory at Johnson Space Center. Additional images taken by astronauts and cosmonauts can be viewed at the NASA-JSC Gateway to Astronaut Photography

  13. Geological map of Bare Mountain, Nye County, Nevada

    SciTech Connect

    Monsen, S.A.; Carr, M.D.; Reheis, M.C.; Orkild, P.P.

    1992-12-31

    Bare Mountain comprises the isolated complex of mountain peaks southeast of the town of Beatty in southern Nye County, Nevada. This small mountain range lies between the alluvial basins of Crater Flat to the east and the northern Amargosa Desert to the southwest. The northern boundary of the range is less well defined, but for this report, the terrane of faulted Miocene volcanic rocks underlying Beatty Mountain and the unnamed hills to the east are considered to be the northernmost part of Bare Mountain. The southern tip of the mountain range is at Black Marble, the isolated hill at the southeast corner of the map. The main body of the range, between Fluorspar Canyon and Black Marble, is a folded and complexly faulted, but generally northward-dipping (or southward-dipping and northward-overturned), sequence of weakly to moderately metamorphosed upper Proterozoic and Paleozoic marine strata, mostly miogeoclinal (continental shelf) rocks. The geology of Bare Mountain is mapped at a scale of 1:24,000.

  14. Mountains and arid climates of middle latitudes

    SciTech Connect

    Manabe, S.; Broccoli, A.J. )

    1990-01-12

    Simulations from a global climate model with and without orography have been used to investigate the role of mountains in maintaining extensive arid climates in middle latitudes of the Northern hemisphere. Dry climates similar to those observed were simulated over central Asia and western interior North America in the experiment with mountains, whereas relatively moist climates were simulated in these areas in the absence of orography. The experiments suggest that these interior regions are dry because general subsidence and relatively infrequent storm development occur upstream of orographically induced stationary wave troughs. Downstream of these troughs, precipitation-bearing storms develop frequently in association with strong jet streams. In contrast, both atmospheric circulation and precipitation were more zonally symmetric in the experiment without mountains. In addition, orography reduces the moisture transport into the continental interiors from nearby oceanic sources. The relative soil wetness of these regions in the experiment without mountains is consistent with paleoclimatic evidence of less aridity during the late Tertiary, before substantial uplift of the Rocky Mountains and Tibetan Plateau is believed to have occurred.

  15. Atmospheric deposition maps for the Rocky Mountains

    USGS Publications Warehouse

    Nanus, L.; Campbell, D.H.; Ingersoll, G.P.; Clow, D.W.; Mast, M.A.

    2003-01-01

    Variability in atmospheric deposition across the Rocky Mountains is influenced by elevation, slope, aspect, and precipitation amount and by regional and local sources of air pollution. To improve estimates of deposition in mountainous regions, maps of average annual atmospheric deposition loadings of nitrate, sulfate, and acidity were developed for the Rocky Mountains by using spatial statistics. A parameter-elevation regressions on independent slopes model (PRISM) was incorporated to account for variations in precipitation amount over mountainous regions. Chemical data were obtained from the National Atmospheric Deposition Program/National Trends Network and from annual snowpack surveys conducted by the US Geological Survey and National Park Service, in cooperation with other Federal, State and local agencies. Surface concentration maps were created by ordinary kriging in a geographic information system, using a local trend and mathematical model to estimate the spatial variance. Atmospheric-deposition maps were constructed at 1-km resolution by multiplying surface concentrations from the kriged grid and estimates of precipitation amount from the PRISM model. Maps indicate an increasing spatial trend in concentration and deposition of the modeled constituents, particularly nitrate and sulfate, from north to south throughout the Rocky Mountains and identify hot-spots of atmospheric deposition that result from combined local and regional sources of air pollution. Highest nitrate (2.5-3.0kg/ha N) and sulfate (10.0-12.0kg/ha SO4) deposition is found in northern Colorado.

  16. Hopa Mountain and the Idea of Highlander: A Mission Driven by a Philosophy

    ERIC Educational Resources Information Center

    Branch, Kirk; Sachatello-Sawyer, Bonnie

    2013-01-01

    Hopa Mountain is a nonprofit organization committed to developing citizen leaders in rural and tribal communities in the Northern Rockies. The mission of Hopa Mountain is rooted in the principle that the local people have within themselves the strength and wisdom to bring about community change. This mission was inspired by the broader philosophy…

  17. Northern plants and ozone.

    PubMed

    Manninen, Sirkku; Huttunen, Satu; Tømmervik, Hans; Hole, Lars R; Solberg, Sverre

    2009-12-01

    Forests in northern Fennoscandia are mainly composed of the O3-sensitive species--Scots pine and downy, mountain, and silver birches. Seminatural vegetation also contributes to biodiversity, carbon cycling, and ecosystem services as a part of forests, mires, meadows, and road verges. Fumigation experiments show that current O3 concentrations of 30-50 ppb reduce plant biomass production and reproduction. Visible foliar injury is attributable to peak O3 concentrations and relates to fast phenological development and high growth rate. Trees can acclimate to O3-induced water stress by producing more xeromorphic leaves or needles. The direct effects of O3 on grassland vegetation also translate to changes in the structure and size of the soil microbial community, and ecosystem N cycling. It is necessary to reduce the emission of O3 precursors and maintain high biodiversity to protect northern ecosystems. Regular, systematic, countrywide monitoring and validation as well as quantification of the effects of O3 on plants in the Nordic countries are also necessary. PMID:20175438

  18. Massanutten Mountain, Virginia, USA (Anaglyph)

    NASA Technical Reports Server (NTRS)

    2003-01-01

    Massanutten Mountain lies in the Shenandoah Valley of northern Virginia. Rock layers in the mountain are folded downward in an overall 'U' shape (called a syncline) which accounts for its peculiar double ridge shape with a highly elongated valley between. The ridges have formed because they are capped with a sandstone layer which is resistant to weathering and erosion. Limestones and shales are less resistant and form the lowlands and valleys. The north and south forks of the Shenandoah River flank Massanutten Mountain and display unusually pronounced meander patterns. Other layered sedimentary rocks form other ridgeline patterns in the Allegheny Mountains, to the upper left. But the igneous and metamorphic (crystalline) rocks of the Blue Ridge Mountains erode into a very different topographic pattern to the southeast. This small area provides an excellent example rock type, geologic structure, and fluvial (stream) processes all influencing landform development.

    This anaglyph was produced by first shading a preliminary elevation model from data acquired by the Shuttle Radar Topography Mission. The stereoscopic effect was then created by generating two differing perspectives, one for each eye. When viewed through special glasses, the result is a vertically exaggerated view of the Earth's surface in its full three dimensions. Anaglyph glasses cover the left eye with a red filter and cover the right eye with a blue filter.

    Elevation data used in this image were acquired by the Shuttle Radar Topography Mission aboard the Space Shuttle Endeavour, launched on February 11, 2000. The mission used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar that flew twice on the Space Shuttle Endeavour in 1994. The Shuttle Radar Topography Mission was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C

  19. Linking metamorphic textures to U-Pb monazite in-situ geochronology to determine the age and nature of aluminosilicate-forming reactions in the northern Monashee Mountains, British Columbia

    NASA Astrophysics Data System (ADS)

    Gervais, Félix; Hynes, Andrew

    2013-02-01

    The Monashee Mountains of the Canadian Cordillera are thought to expose a classic Barrovian-facies series of isograds. The timing of aluminosilicate growth in the region was determined for four pelitic schist samples by combining textural relationships with monazite compositional zoning and monazite U-Pb geochronology conducted directly on thin-sections by the laser ablation method. Three distinct phases of kyanite growth are recorded in the kyanite zone: at c. 153 Ma, between 122 and 94 Ma and between 76 and 58 Ma. For each phase, monazite and garnet grew synchronously with kyanite, probably by a reaction involving the breakdown of staurolite. In contrast, sillimanite growth by muscovite dehydration melting occurred at or before c. 104 Ma in the sillimanite zone, and retrograde sillimanite grew in schists previously metamorphosed at the kyanite grade during the first two phases by the influx of hot, acidic fluids during top-to-the-east shearing at ca. 71 Ma. These results indicate that rocks metamorphosed at different places and different times in the orogen were juxtaposed prior to being overprinted at the sillimanite grade in the Late Cretaceous-Early Paleocene during the influx of hot fluids in a structurally coherent body deforming by easterly directed shearing. This study also provides new insight into monazite petrogenesis and suggests that, at least in some circumstances, monazite formation is linked to the staurolite-out reaction that produces kyanite.

  20. Northern Nutrition.

    ERIC Educational Resources Information Center

    Northwest Territories Dept. of Education, Yellowknife.

    This guide contains nutrition information and nutrition education strategies aimed at residents of the Canadian Arctic. Section I: (1) defines nutrition terms; (2) describes the sources and functions of essential nutrients; (3) explains Canada's food guide and special considerations for the traditional northern Native diet and for lactose…

  1. Mesozoic and early Tertiary paleostructure and sedimentology of central Wasatch Mountains, Uinta Mountains, and Uinta basin

    SciTech Connect

    Picard, M.D.; Bruhn, R.L.; Beck, S.L.

    1983-08-01

    During latest Cretaceous-Eocene time, 5,000 m (16,000 ft) of beds were deposited in central and northeast Utah. In the Late Cretaceous, sediment derived from the Sevier-Laramide thrust belt was transported to the east and southeast. Southerly paleocurrent directions in the base of the Currant Creek Formation (Maestrichtian) raise the possibility that uplift of the Uintas may have begun by then. The thrust belt continued as a major highland during the early Paleocene, and major uplift of the Uintas occurred. By the middle Paleocene there was an extensive lake which regressed during the late Paleocene as uplift of the Uintas continued. Lake Uinta reached its maximum size during the middle Eocene. Lower (early Duchesnean) and upper (Late Duchesnean) conglomeratic intervals record major episodes of uplift in the Uintas during latest Eocene. Structurally, the Wasatch Mountains are part of a marginal foreland fold and thrust belt. In the northern Wasatch Mountains, pre-Late Cretaceous thrust fault plates were folded in part of a large, ramp-anticline that is cored by allochthonous, crystalline basement . Foreland thrust belt structures in the central Wasatch Mountains were folded about the east-trending Uinta axis as the Uinta Mountains formed. Eastward movement on the Hogsback thrust during the Paleocene was transferred onto the adjacent Uinta axis and Uinta Mountains structure, causing about 20 km (12 mi) of sinistral slip in the western Uinta Mountains. A south-dipping fault ramp was located beneath the Uinta Mountains and extended to depths of 15 to 20 km (9 to 12 mi). Oblique-slip on this ramp probably resulted in about 20 km (12 mi) of crustal shortening perpendicular to the trend of the mountains.

  2. Sacred Mountains Scholars Gaining a New Window on the Universe.

    ERIC Educational Resources Information Center

    Ainsworth, Diane

    1992-01-01

    Describes the Sacred Mountains Scholars Program, a collaborative training program of the National Aeronautics and Space Administration's (NASA) Jet Propulsion Laboratory and Northern Arizona University that gives American Indian undergraduates the opportunity to explore engineering, business, and space science careers during summer on-the-job…

  3. Nature and continuity of the Sundance Fault, Yucca Mountain, Nevada

    SciTech Connect

    Potter, Christopher J.; Dickerson, Robert P.; Day, Warren C.

    2000-01-12

    This report describes the detailed geologic mapping (1:2,400 scale) that was performed in the northern part of the potential nuclear waste repository area at Yucca Mountain, Nevada, to determine the nature and extent of the Sundance Fault zone and to evaluate structural relations between the Sundance and other faults.

  4. Association of Different Genetic Types of Francisella-Like Organisms with the Rocky Mountain Wood Tick (Dermacentor andersoni) and the American Dog Tick (Dermacentor variabilis) in Localities Near Their Northern Distributional Limits

    PubMed Central

    Chilton, Neil B.

    2012-01-01

    Dermacentor andersoni and Dermacentor variabilis from allopatric and sympatric populations near their northern distributional limits were examined for the presence of Francisella species using molecular techniques that targeted 373 bp of the 16S rRNA gene. Although there was no evidence for the presence of Francisella tularensis in any tick, Francisella-like endosymbionts (FLEs) were common in D. andersoni and D. variabilis adults and immatures. A significantly greater proportion of female ticks contained FLEs compared to male ticks. In addition, significantly more D. variabilis adult individuals contained multiple FLE sequence types than did D. andersoni adults. Ten different types of FLEs were identified based on the sequence data, which has implications for diagnostic tests and epidemiological studies of F. tularensis in tick populations in Canada. The three most prevalent types of FLEs have been detected previously in D. andersoni or D. variabilis from other parts of their distributional ranges, whereas the other seven FLE types have not been reported previously. A comparison of the FLEs from both allopatric and sympatric populations of these two tick species provided insight into the relative host-specificity and the modes of transmission of these tick-borne bacteria. In general, each FLE type was specific for one tick species, suggesting vertical transmission of each bacterium. However, there were a few instances of potential cross-transfer of two FLE types to the other tick species at locations where D. andersoni and D. variabilis occurred in sympatry, suggesting that there may be occasional horizontal transmission of some FLEs. PMID:22179251

  5. 2. VIEW OF NORTHERN WATER TANK (FEATURE B2), FACING SOUTH. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. VIEW OF NORTHERN WATER TANK (FEATURE B-2), FACING SOUTH. THE ADIT ROAD IS SHOWN IN THE RIGHT SIDE OF THE PHOTO. - Nevada Lucky Tiger Mill & Mine, Water Tanks, East slope of Buckskin Mountain, Paradise Valley, Humboldt County, NV

  6. The effects of orography on midlatitude Northern Hemisphere dry climates

    SciTech Connect

    Broccoli, A.J.; Manabe, S. )

    1992-11-01

    The role of mountains in maintaining extensive midlatitude arid regions in the Northern Hemisphere was studied utilizing simulations from the GFDL GMC with and without orography. In the integration with mountains, dry climates were simulated over the interior of North America and central Asia, in good agreement with the observed climate. The results from these experiments indicate that midlatitude dryness is due largely to the existence of orography. 38 refs.

  7. Chronology of latest Pleistocene mountain glaciation in the western Wasatch Mountains, Utah, U.S.A.

    NASA Astrophysics Data System (ADS)

    Laabs, Benjamin J. C.; Marchetti, David W.; Munroe, Jeffrey S.; Refsnider, Kurt A.; Gosse, John C.; Lips, Elliott W.; Becker, Richard A.; Mickelson, David M.; Singer, Brad S.

    2011-09-01

    Understanding the timing of mountain glacier and paleolake expansion and retraction in the Great Basin region of the western United States has important implications for regional-scale climate change during the last Pleistocene glaciation. The relative timing of mountain glacier maxima and the well-studied Lake Bonneville highstand has been unclear, however, owing to poor chronological limits on glacial deposits. Here, this problem is addressed by applying terrestrial cosmogenic 10Be exposure dating to a classic set of terminal moraines in Little Cottonwood and American Fork Canyons in the western Wasatch Mountains. The exposure ages indicate that the main phase of deglaciation began at 15.7 ± 1.3 ka in both canyons. This update to the glacial chronology of the western Wasatch Mountains can be reconciled with previous stratigraphic observations of glacial and paleolake deposits in this area, and indicates that the start of deglaciation occurred during or at the end of the Lake Bonneville hydrologic maximum. The glacial chronology reported here is consistent with the growing body of data suggesting that mountain glaciers in the western U.S. began retreating as many as 4 ka after the start of northern hemisphere deglaciation (at ca. 19 ka).

  8. Estimates of cloud water deposition at Mountain Acid Deposition Program sites in the Appalachian Mountains.

    PubMed

    Baumgardner, Ralph E; Isil, Selma S; Lavery, Thomas F; Rogers, Christopher M; Mohnen, Volker A

    2003-03-01

    Cloud water deposition was estimated at three high-elevation sites in the Appalachian Mountains of the eastern United States (Whiteface Mountain, NY; Whitetop Mountain, VA; and Clingman's Dome, TN) from 1994 through 1999 as part of the Mountain Acid Deposition Program (MADPro). This paper provides a summary of cloud water chemistry, cloud liquid water content, cloud frequency, estimates of cloud water deposition of sulfur and nitrogen species, and estimates of total deposition of sulfur and nitrogen at these sites. Other cloud studies in the Appalachians and their comparison to MADPro are also summarized. Whiteface Mountain exhibited the lowest mean and median concentrations of sulfur and nitrogen ions in cloud water, while Clingman's Dome exhibited the highest mean and median concentrations. This geographic gradient is partly an effect of the different meteorological conditions experienced at northern versus southern sites in addition to the difference in pollution content of air masses reaching the sites. All sites measured seasonal cloud water deposition rates of SO4(2-) greater than 50 kg/ha and NO3(-) rates of greater than 25 kg/ha. These high-elevation sites experienced additional deposition loading of SO4(2-) and NO3(-) on the order of 6-20 times greater compared with lower elevation Clean Air Status and Trends Network (CASTNet) sites. Approximately 80-90% of this extra loading is from cloud deposition. PMID:12661689

  9. Late Cretaceous paleomagnetism of the Tucson Mountains: implications for vertical axis rotations in south central Arizona

    USGS Publications Warehouse

    Hagstrum, J.T.; Lipman, P.W.

    1991-01-01

    The Tucson Mountains of southern Arizona are the site of an Upper Cretaceous caldera from which the rhyolitic Cat Mountain Tuff was erupted at about 72 Ma. Two magnetic units within the Cat Mountain Tuff are distinguished by paleomagnetic data in both the northern and southern Tucson Mountains. The available paleomagnetic data indicate that rocks in southern Arizona have not remained unrotated with respect to North America since Late Cretaceous time and that vertical axis rotations may have played an important role in the region during Laramide deformation. -from Authors

  10. Mountaineering fatalities on Denali.

    PubMed

    McIntosh, Scott E; Campbell, Aaron D; Dow, Jennifer; Grissom, Colin K

    2008-01-01

    Mount McKinley, or Denali, is the tallest mountain in North America and attracts over 1,000 climbers annually from around the world. Since Denali is located within a national park, the National Park Service (NPS) manages mountaineering activities and attempts to maintain a balance of an adventurous experience while promoting safety. We retrospectively reviewed the fatalities on Denali from 1903 to 2006 to assist the NPS, medical personnel, and mountaineers improve safety and reduce fatalities on the mountain. Historical records and the NPS climber database were reviewed. Demographics, mechanisms, and circumstances surrounding each fatality were examined. Fatality rates and odds ratios for country of origin were calculated. From 1903 through the end of the 2006 climbing season, 96 individuals died on Denali. The fatality rate is declining and is 3.08/1,000 summit attempts. Of the 96 deaths, 92% were male, 51% occurred on the West Buttress route, and 45% were due to injuries sustained from falls. Sixty-one percent occurred on the descent and the largest number of deaths in 1 year occurred in 1992. Climbers from Asia had the highest odds of dying on the mountain. Fatalities were decreased by 53% after a NPS registration system was established in 1995. Although mountaineering remains a high-risk activity, safety on Denali is improving. Certain groups have a significantly higher chance of dying. Registration systems and screening methods provide ways to target at-risk groups and improve safety on high altitude mountains such as Denali. PMID:18331224

  11. Mantle Subduction and Uplift of Intracontinental Mountains: A Case Study from the Chinese Tianshan Mountains within Eurasia

    PubMed Central

    Li, Jinyi; Zhang, Jin; Zhao, Xixi; Jiang, Mei; Li, Yaping; Zhu, Zhixin; Feng, Qianwen; Wang, Lijia; Sun, Guihua; Liu, Jianfeng; Yang, Tiannan

    2016-01-01

    The driving mechanism that is responsible for the uplift of intracontinental mountains has puzzled geologists for decades. This study addresses this issue by using receiver function images across the Chinese Tianshan Mountains and available data from both deep seismic profiles and surface structural deformation. The near-surface structural deformation shows that the Tianshan crust experienced strong shortening during the Cenozoic. The receiver function image across the Tianshan Mountains reveals that the lithosphere of the Junggar Basin to the north became uncoupled along the Moho, and the mantle below the Moho subducted southwards beneath the northern part of the Tianshan Mountains, thereby thickening the overlying crust. Similar deep structures, however, are not observed under the Tarim Basin and the adjacent southern Tianshan Mountains. This difference in the deep structures correlates with geomorphological features in the region. Thus, a new model of mantle subduction, herein termed M-type subduction, is proposed for the mountain-building processes in intracontinental compressional settings. The available geomorphological, geological and seismic data in the literatures show that this model is probably suitable for other high, linear mountains within the continent. PMID:27353861

  12. Mantle Subduction and Uplift of Intracontinental Mountains: A Case Study from the Chinese Tianshan Mountains within Eurasia

    NASA Astrophysics Data System (ADS)

    Li, Jinyi; Zhang, Jin; Zhao, Xixi; Jiang, Mei; Li, Yaping; Zhu, Zhixin; Feng, Qianwen; Wang, Lijia; Sun, Guihua; Liu, Jianfeng; Yang, Tiannan

    2016-06-01

    The driving mechanism that is responsible for the uplift of intracontinental mountains has puzzled geologists for decades. This study addresses this issue by using receiver function images across the Chinese Tianshan Mountains and available data from both deep seismic profiles and surface structural deformation. The near-surface structural deformation shows that the Tianshan crust experienced strong shortening during the Cenozoic. The receiver function image across the Tianshan Mountains reveals that the lithosphere of the Junggar Basin to the north became uncoupled along the Moho, and the mantle below the Moho subducted southwards beneath the northern part of the Tianshan Mountains, thereby thickening the overlying crust. Similar deep structures, however, are not observed under the Tarim Basin and the adjacent southern Tianshan Mountains. This difference in the deep structures correlates with geomorphological features in the region. Thus, a new model of mantle subduction, herein termed M-type subduction, is proposed for the mountain-building processes in intracontinental compressional settings. The available geomorphological, geological and seismic data in the literatures show that this model is probably suitable for other high, linear mountains within the continent.

  13. Mantle Subduction and Uplift of Intracontinental Mountains: A Case Study from the Chinese Tianshan Mountains within Eurasia.

    PubMed

    Li, Jinyi; Zhang, Jin; Zhao, Xixi; Jiang, Mei; Li, Yaping; Zhu, Zhixin; Feng, Qianwen; Wang, Lijia; Sun, Guihua; Liu, Jianfeng; Yang, Tiannan

    2016-01-01

    The driving mechanism that is responsible for the uplift of intracontinental mountains has puzzled geologists for decades. This study addresses this issue by using receiver function images across the Chinese Tianshan Mountains and available data from both deep seismic profiles and surface structural deformation. The near-surface structural deformation shows that the Tianshan crust experienced strong shortening during the Cenozoic. The receiver function image across the Tianshan Mountains reveals that the lithosphere of the Junggar Basin to the north became uncoupled along the Moho, and the mantle below the Moho subducted southwards beneath the northern part of the Tianshan Mountains, thereby thickening the overlying crust. Similar deep structures, however, are not observed under the Tarim Basin and the adjacent southern Tianshan Mountains. This difference in the deep structures correlates with geomorphological features in the region. Thus, a new model of mantle subduction, herein termed M-type subduction, is proposed for the mountain-building processes in intracontinental compressional settings. The available geomorphological, geological and seismic data in the literatures show that this model is probably suitable for other high, linear mountains within the continent. PMID:27353861

  14. Nature of thrusting along western flank of Bighorn Mountains, Wyoming

    SciTech Connect

    Noggle, K.S.

    1986-08-01

    The northern portion of the Bighorn Mountains is characterized by opposed mountain-front thrusts, of which the southwest direction is dominant. Blind basement thrusts along the northeastern flank do not pierce the folded Paleozoic cover; whereas on the western flank, southwest-directed thrust segments expose Precambrian rocks along a 24-km (14-mi) extent. Field studies on the western flank show evidence of four major southwest-directed thrust segments delineated by tear-fault boundaries, which include from northwest to southeast: (1) the Five Springs thrust, a low-angle, out-of-the-syncline fault mainly involving the sedimentary sequence; (2) the Bear Creek thrust, a continuation of the Five Springs out-of-the-syncline fault; (3) the South Beaver Creek thrust, which juxtaposes Precambrian rocks against a tectonically thinned, overturned anticlinal limb of Mississippian through Jurassic rocks and which is inward from an out-of-the-syncline thrust involving little displacement of Jurassic formations; and (4) a mountain-front reentrant that coincides with the zone where the South Beaver Creek thrust continues beneath Paleozoic cover, causing the upper flexure of a double monocline. The central portion of the Bighorn Mountains is thrust eastward, whereas the northern portion is thrust southwestward with much less displacement. The segmented association of southwest-directed basement thrusts along the western flank of the northern Bighorns is indicative of the major transport direction for that portion of the Bighorn uplift.

  15. Mountain-Top Science

    ERIC Educational Resources Information Center

    Cussen, John P.

    1976-01-01

    Described is the Talcott Mountain Science Center for Student Involvement, Inc., near Hartford, Connecticut, and the programs in natural science offered at the facility and by center personnel in local schools. (SL)

  16. Acute mountain sickness

    MedlinePlus

    High altitude cerebral edema; Altitude anoxia; Altitude sickness; Mountain sickness; High altitude pulmonary edema ... If you have fluid in your lungs (pulmonary edema), treatment may include: Oxygen A high blood pressure ...

  17. YUCCA MOUNTAIN SITE DESCRIPTION

    SciTech Connect

    A.M. Simmons

    2004-04-16

    The ''Yucca Mountain Site Description'' summarizes, in a single document, the current state of knowledge and understanding of the natural system at Yucca Mountain. It describes the geology; geochemistry; past, present, and projected future climate; regional hydrologic system; and flow and transport within the unsaturated and saturated zones at the site. In addition, it discusses factors affecting radionuclide transport, the effect of thermal loading on the natural system, and tectonic hazards. The ''Yucca Mountain Site Description'' is broad in nature. It summarizes investigations carried out as part of the Yucca Mountain Project since 1988, but it also includes work done at the site in earlier years, as well as studies performed by others. The document has been prepared under the Office of Civilian Radioactive Waste Management quality assurance program for the Yucca Mountain Project. Yucca Mountain is located in Nye County in southern Nevada. The site lies in the north-central part of the Basin and Range physiographic province, within the northernmost subprovince commonly referred to as the Great Basin. The basin and range physiography reflects the extensional tectonic regime that has affected the region during the middle and late Cenozoic Era. Yucca Mountain was initially selected for characterization, in part, because of its thick unsaturated zone, its arid to semiarid climate, and the existence of a rock type that would support excavation of stable openings. In 1987, the United States Congress directed that Yucca Mountain be the only site characterized to evaluate its suitability for development of a geologic repository for high-level radioactive waste and spent nuclear fuel.

  18. MIDDLE MOUNTAIN-TOBACCO ROOT ROADLESS AREA, MONTANA.

    USGS Publications Warehouse

    O'Neill, J. Michael; Cather, Eric E.

    1984-01-01

    A mineral-resource survey of the northern part of the Tobacco Root Mountains, Montana determined that the area included in or enclosed by the Middle Mountain-Tobacco Root Roadless Area contains serveral areas of probable or substantiated mineral-resource potential. Most of the mineralized areas are located in or adjacent to intrusive rocks of Late Cretaceous age. Mineral resources are probably of three types: disseminated and stockwork copper and molybdenum in porphyry-type deposits; gold-silver-quartz veins; and gold-bearing silicified zones. No energy resources were identified in this study.

  19. Middle Miocene Displacement Along the Rand Detachment Fault, Rand Mountains

    NASA Astrophysics Data System (ADS)

    Shulaker, D. Z.; Grove, M. J.

    2015-12-01

    Laramide flat-slab subduction extinguished Sierra Nevada pluton emplacement in southern California by ca. 85 Ma as trench-derived sediments were underthrust and accreted beneath arc basement. These relationships are well illustrated in the Rand Mountains, situated just south of the Garlock fault in the northwestern Mojave Desert. Here, accreted rocks within the Rand Mountains are referred to as Rand Schist. The Rand Detachment fault juxtaposes Rand Schist beneath 87 Ma Sierran granitoids. New zircon (U-Th)/He age results from schist and basement juxtaposed across the Rand Detachment fault are 15 ± 3 Ma and 30 ± 5 Ma, respectively. When considered within the context of previously reported thermochronology from the Rand Mountains, our data shows that the Rand Detachment fault in the Rand Mountains is a middle Miocene fault that facilitated extension of the northwest Mojave Desert. This timing is in temporal and spatial agreement with regional extension throughout the Mojave triggered by northern migration of the slab window after collision of the Mendocino Triple Junction with the southern California margin. Further evidence of slab-window-related magmatism in the easternmost Rand Mountains is provided by the 19 Ma Yellow Aster pluton and 19 Ma rhyolite porphyry. It is possible that Miocene extension re-activated an older structure within the Rand Mountains. For example, a similar low-angle fault juxtaposing schist and basement present in the San Emigdio Mountains is believed to have accommodated large scale Late Cretaceous displacement, exhuming Rand Schist and overlying deepest Sierran basement to shallow crustal levels by 77 Ma [1]. However, 68-72 Ma phengite cooling ages and other thermochronology from the Rand Mountains indicates that any pre-Miocene extension in this area must postdate that in the San Emigdio Mountains. [1] Chapman et al., 2012. Geosphere, 8, 314-341.

  20. Mammoth Mountain, California broadband seismic experiment

    NASA Astrophysics Data System (ADS)

    Dawson, P. B.; Pitt, A. M.; Wilkinson, S. K.; Chouet, B. A.; Hill, D. P.; Mangan, M.; Prejean, S. G.; Read, C.; Shelly, D. R.

    2013-12-01

    Mammoth Mountain is a young cumulo-volcano located on the southwest rim of Long Valley caldera, California. Current volcanic processes beneath Mammoth Mountain are manifested in a wide range of seismic signals, including swarms of shallow volcano-tectonic earthquakes, upper and mid-crustal long-period earthquakes, swarms of brittle-failure earthquakes in the lower crust, and shallow (3-km depth) very-long-period earthquakes. Diffuse emissions of C02 began after a magmatic dike injection beneath the volcano in 1989, and continue to present time. These indications of volcanic unrest drive an extensive monitoring effort of the volcano by the USGS Volcano Hazards Program. As part of this effort, eleven broadband seismometers were deployed on Mammoth Mountain in November 2011. This temporary deployment is expected to run through the fall of 2013. These stations supplement the local short-period and broadband seismic stations of the Northern California Seismic Network (NCSN) and provide a combined network of eighteen broadband stations operating within 4 km of the summit of Mammoth Mountain. Data from the temporary stations are not available in real-time, requiring the merging of the data from the temporary and permanent networks, timing of phases, and relocation of seismic events to be accomplished outside of the standard NCSN processing scheme. The timing of phases is accomplished through an interactive Java-based phase-picking routine, and the relocation of seismicity is achieved using the probabilistic non-linear software package NonLinLoc, distributed under the GNU General Public License by Alomax Scientific. Several swarms of shallow volcano-tectonic earthquakes, spasmodic bursts of high-frequency earthquakes, a few long-period events located within or below the edifice of Mammoth Mountain and numerous mid-crustal long-period events have been recorded by the network. To date, about 900 of the ~2400 events occurring beneath Mammoth Mountain since November 2011 have

  1. The Geologic Story of the Uinta Mountains

    USGS Publications Warehouse

    Hansen, Wallace R.

    1969-01-01

    The opening of the West after the Civil War greatly stimulated early geologic exploration west of the 100th Meridian. One of the areas first studied, the Uinta Mountains region, gained wide attention as a result of the explorations of three Territorial Surveys, one headed by John Wesley Powell, one by Clarence King, and one by Ferdinand V. Hayden. Completion of the Union Pacific Railroad across southern Wyoming 100 years ago, in 1869, materially assisted geologic exploration, and the railheads at Green River and Rock Springs greatly simplified the outfitting of expeditions into the mountains. The overlap of the Powell, King, and Hayden surveys in the Uinta Mountains led to efforts that were less concerted than competitive and not without acrimony. Many parts of the area were seen by all three parties at almost the same time. Duplication was inevitable, of course, but all three surveys contributed vast quantities of new knowledge to the storehouse of geology, and many now-basic concepts arose from their observations. Powell's area of interest extended mainly southward from the Uinta Mountains to the Grand Canyon, including the boundless plateaus and canyons of southern Utah and northern Arizona. King's survey extended eastward from the High Sierra in California to Cheyenne, Wyoming, and encompassed a swath of country more than 100 miles wide. Hayden's explorations covered an immense region of mountains and basins from Yellowstone Park in Wyoming southeast throughout most of Colorado. Powell first entered the Uinta Mountains in the fall of 1868, having traveled north around the east end of the range from the White River country to Green River, Wyoming, then south over a circuitous route to Flaming Gorge and Browns Park, and finally back to the White River, where he spent the winter. In 1869, after reexamining much of the area visited the previous season, Powell embarked on his famous 'first boat trip' down the Green and Colorado Rivers. This trip was more exploratory

  2. 9. Rear of northern kiln group, looking northeast. Although not ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. Rear of northern kiln group, looking northeast. Although not visible from this distance, the Viola Mine was located in the mountain range in the background. - Warren King Charcoal Kilns, 5 miles west of Idaho Highway 28, Targhee National Forest, Leadore, Lemhi County, ID

  3. The Conifers of the Northern Rockies. Bulletin, 1917, No. 53

    ERIC Educational Resources Information Center

    Kirkwood, J. F.

    1918-01-01

    The purpose of this bulletin is to enable persons not technically trained in botany to identify the coniferous species of the northern Rocky Mountain region lying within the United States. Forest trees of all kinds have interest for all people. Familiar and affection knowledge of them has culture value of a very fine kind. For the people of some…

  4. 31. SOUTH PLANT NORTHERN EDGE, SHOWING CELL BUILDING (BUILDING 242) ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    31. SOUTH PLANT NORTHERN EDGE, SHOWING CELL BUILDING (BUILDING 242) AT LEFT, LABORATORY (BUILDING 241) AT CENTER AND CAUSTIC FUSION PLANT (BUILDING 254) AT RIGHT. VIEW TO SOUTHWEST. - Rocky Mountain Arsenal, Bounded by Ninety-sixth Avenue & Fifty-sixth Avenue, Buckley Road, Quebec Street & Colorado Highway 2, Commerce City, Adams County, CO

  5. Flathead River Basin Hydrologic Observatory, Northern Rocky Mountains

    NASA Astrophysics Data System (ADS)

    Woessner, W. W.; Running, S. W.; Potts, D. F.; Kimball, J. S.; Deluca, T. H.; Fagre, D. B.; Makepeace, S.; Hendrix, M. S.; Lorang, M. S.; Ellis, B. K.; Lafave, J.; Harper, J.

    2004-12-01

    We are proposing the 22, 515 km2 glacially-sculpted Flathead River Basin located in Montana and British Columbia as a Hydrologic Observatory. This hydrologic landscape is diverse and includes large pristine watersheds, rapidly developing intermountain valleys, and a 95 km2 regulated reservoir and 510 km2 lake. The basin has a topographic gradient of over 2,339 m, and spans high alpine to arid climatic zones and a range of biomes. Stream flows are snow-melt dominated and underpinned by groundwater baseflow. The site headwaters contain 37 glaciers and thousands of square kilometers of watersheds in which fire and disease are the only disturbances. In contrast, the HO also contains watersheds at multiple scales that were dominated by glaciers within the last 100 years but are now glacier free, impacted by timber harvests and fires of varying ages to varying degrees, modified by water management practices including irrigation diversion and dams, and altered by development for homes, cities and agriculture. This Observatory provides a sensitive monitor of historic and future climatic shifts, air shed influences and impacts, and the consequences of land and water management practices on the hydrologic system. The HO watersheds are some of the only pristine watersheds left in the contiguous U.S.. They provide critical habitat for key species including the native threaten bull trout and lynx, and the listed western cutthroat trout, bald eagle, gray wolf and the grizzly bear. For the last several thousand years this system has been dominated by snow-melt runoff and moderated by large quantities of water stored in glacial ice. However, the timing and magnitude of droughts and summer flows have changed dramatically. With the information that can be gleaned from sediment cores and landscape records at different scales, this HO provides scientists with opportunities to establish baseline watershed conditions and data on natural hydrologic variability within the system. Such a context frames the current and further observations and assists with translating measured changes into links with the varied HO ecosystems.

  6. Improving climate change knowledge in the Northern Rocky Mountains, USA.

    NASA Astrophysics Data System (ADS)

    Fagre, D. B.

    2007-12-01

    There are many challenges to involving authentic scientists in classroom and media communications and one is the willingness of scientists to participate. The reticence of scientists to be involved has various roots but one solution is to partner with individuals and institutions experienced in outreach. At Glacier National Park, USGS scientists have worked closely with the Crown of the Continent Research and Learning Center, part of a U.S. National Park Service initiative to improve science-based decisionmaking. The controversial topic of global warming has been embraced as a science theme and research results have been crafted into compact messages for various audiences. The interpretive staff developed a core curriculum on climate change and receive annual training directly from scientists on the most recent research. The interpretive staff interact directly while leading hikes, giving campfire talks, and at visitor centers with many of the 2.2 million visitors each year who are generally more receptive while on vacation than during busy daily lives. Wayside exhibits along the Going-to- the-Sun Road explain climate change and melting glaciers, free brochures describe other aspects of climate change, electronic kiosks have short movies, and a newsletter handout at the entrance station has a science feature in it. To aid this effort, scientists have worked harder at developing compelling graphics, creating animations, serving more media-savvy materials on websites, and providing CDs with scientific data and backup materials. A website developed for serving historic and current photographs of glaciers has been so popular with the media that it has received as many as 8,000 hits in a day. Active participation by scientists in network newscasts and documentaries may involve up to 2 days of hiking TV crews into the backcountry and much effort in reviewing scripts and confirming information. This is essential to keeping credible information going to the public despite the considerable time investments by scientists. Articles in the print media are facilitated by maintaining a photograph/graphic database of research activities but working directly with reporters is still the critical link. Finally, new approaches have been explored by collaborating with artists to take science messages to different audiences.

  7. Mountain Home Well - Photos

    DOE Data Explorer

    Shervais, John

    2012-01-11

    The Snake River Plain (SRP), Idaho, hosts potential geothermal resources due to elevated groundwater temperatures associated with the thermal anomaly Yellowstone-Snake River hotspot. Project HOTSPOT has coordinated international institutions and organizations to understand subsurface stratigraphy and assess geothermal potential. Over 5.9km of core were drilled from three boreholes within the SRP in an attempt to acquire continuous core documenting the volcanic and sedimentary record of the hotspot: (1) Kimama, (2) Kimberly, and (3) Mountain Home. The Mountain Home drill hole is located along the western plain and documents older basalts overlain by sediment. Data submitted by project collaborator Doug Schmitt, University of Alberta

  8. Using noble gases to investigate mountain-front recharge

    USGS Publications Warehouse

    Manning, A.H.; Solomon, D.K.

    2003-01-01

    Mountain-front recharge is a major component of recharge to inter-mountain basin-fill aquifers. The two components of mountain-front recharge are (1) subsurface inflow from the mountain block (subsurface inflow), and (2) infiltration from perennial and ephemeral streams near the mountain front (stream seepage). The magnitude of subsurface inflow is of central importance in source protection planning for basin-fill aquifers and in some water rights disputes, yet existing estimates carry large uncertainties. Stable isotope ratios can indicate the magnitude of mountain-front recharge relative to other components, but are generally incapable of distinguishing subsurface inflow from stream seepage. Noble gases provide an effective tool for determining the relative significance of subsurface inflow, specifically. Dissolved noble gas concentrations allow for the determination of recharge temperature, which is correlated with recharge elevation. The nature of this correlation cannot be assumed, however, and must be derived for the study area. The method is applied to the Salt Lake Valley Principal Aquifer in northern Utah to demonstrate its utility. Samples from 16 springs and mine tunnels in the adjacent Wasatch Mountains indicate that recharge temperature decreases with elevation at about the same rate as the mean annual air temperature, but is on average about 2??C cooler. Samples from 27 valley production wells yield recharge elevations ranging from the valley elevation (about 1500 m) to mid-mountain elevation (about 2500 m). Only six of the wells have recharge elevations less than 1800 m. Recharge elevations consistently greater than 2000 m in the southeastern part of the basin indicate that subsurface inflow constitutes most of the total recharge in this area. ?? 2003 Published by Elsevier Science B.V.

  9. Development of Archean crust in the Wind River Mountains, Wyoming

    NASA Technical Reports Server (NTRS)

    Frost, C. D.; Koesterer, M. E.; Koesterer, M. E.; Koesterer, M. E.; Koesterer, M. E.

    1986-01-01

    The Wind River Mountains are a NW-SE trending range composed almost entirely of high-grade Archean gneiss and granites which were thrust to the west over Phanerozoic sediments during the Laramide orogeny. Late Archean granites make up over 50% of the exposed crust and dominates the southern half of the range, while older orthogneisses and magnatites form most of the northen half of the range. Locally these gneisses contain enclaves of supracrustal rocks, which appear to be the oldest preserved rocks in the range. Detailed work in the Medina Mountain area of the central Wind River Mountains and reconnaissance work throughout much of the northern part of the range has allowed definition of the sequence of events which marked crustal development in this area. The sequence of events are described.

  10. The vegetation of Yucca Mountain: Description and ecology

    SciTech Connect

    1996-03-29

    Vegetation at Yucca Mountain, Nevada, was monitored over a six-year period, from 1989 through 1994. Yucca Mountain is located at the northern limit of the Mojave Desert and is the only location being studied as a potential repository for high-level nuclear waste. Site characterization consists of a series of multidisciplinary, scientific investigations designed to provide detailed information necessary to assess the suitability of the Yucca Mountain Site as a repository. This vegetation description establishes a baseline for determining the ecological impact of site characterization activities; it porvides input for site characterization research and modeling; and it clarifies vegetation community dynamics and relationships to the physical environment. A companion study will describe the impact of site characterization of vegetation. Cover, density, production, and species composition of vascular plants were monitored at 48 Ecological Study Plots (ESPs) stratified in four vegetation associations. Precipitation, soil moisture, and maximum and minimum temperatures also were measured at each study plot.

  11. Blue Mountains Ecoregion: Chapter 16 in Status and trends of land change in the Western United States--1973 to 2000

    USGS Publications Warehouse

    Soulard, Christopher E.

    2012-01-01

    The Blue Mountains Ecoregion encompasses approximately 65,461 km² (25,275 mi²) of land bordered on the north by the Columbia Plateau Ecoregion, on the east by the Northern Rockies Ecoregion, on the south by the Snake River Basin and the Northern Basin and Range Ecoregions, and on the west by the Cascades and the Eastern Cascades Slopes and Foothills Ecoregions (fig. 1) (Omernik, 1987; U.S. Environmental Protection Agency, 1997). Most of the Blue Mountains Ecoregion is located within Oregon (83.5 percent); 13.8 percent is in Idaho, and 2.7 percent is in Washington. The Blue Mountains are composed of primarily Paleozoic volcanic rocks, with minor sedimentary, metamorphic, and granitic rocks. Lower mountains and numerous basin-and-range areas, as well as the lack of Quaternary-age volcanoes, distinguish the Blue Mountains from the adjacent Cascade Range (Thorson and others, 2003).

  12. MISR Views Northern Australia

    NASA Technical Reports Server (NTRS)

    2000-01-01

    MISR images of tropical northern Australia acquired on June 1, 2000 (Terra orbit 2413) during the long dry season. Left: color composite of vertical (nadir) camera blue, green, and red band data. Right: multi-angle composite of red band data only from the cameras viewing 60 degrees aft, 60 degrees forward, and nadir. Color and contrast have been enhanced to accentuate subtle details. In the left image, color variations indicate how different parts of the scene reflect light differently at blue, green, and red wavelengths; in the right image color variations show how these same scene elements reflect light differently at different angles of view. Water appears in blue shades in the right image, for example, because glitter makes the water look brighter at the aft camera's view angle. The prominent inland water body is Lake Argyle, the largest human-made lake in Australia, which supplies water for the Ord River Irrigation Area and the town of Kununurra (pop. 6500) just to the north. At the top is the southern edge of Joseph Bonaparte Gulf; the major inlet at the left is Cambridge Gulf, the location of the town of Wyndham (pop. 850), the port for this region. This area is sparsely populated, and is known for its remote, spectacular mountains and gorges. Visible along much of the coastline are intertidal mudflats of mangroves and low shrubs; to the south the terrain is covered by open woodland merging into open grassland in the lower half of the pictures.

    MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is a division of the California Institute of Technology.

  13. Yucca Mountain tuffs

    SciTech Connect

    1996-08-01

    This is a compilation of petrographic slides detailing the microstructure and petrographic character of the tuff deposits associated with the Yucca Mountain radioactive waste repository. It describes crystal structures, clay alterations, and mineral associations. The paper contains a description of the petrographic thin-sections but contains no narrative or conclusions of what the slides suggest with regards to the facility.

  14. DOE's Yucca Mountain Studies.

    ERIC Educational Resources Information Center

    Department of Energy, Washington, DC.

    This booklet is about the disposal of high-level nuclear waste in the United States with a particular focus on Yucca Mountain, Nevada as a repository site. Intended for readers who do not have a technical background, the booklet discusses why scientists and engineers think high-level nuclear waste may be disposed of safely underground. An…

  15. The Strongest Mountain

    ERIC Educational Resources Information Center

    Monnes, Colleen

    2004-01-01

    The article describes an activity for the author's fifth-grade students called "build the strongest mountain." To them, it was not a lesson--it was a challenge. To the author, it was an activity that turned a run-of-the-mill Earth science unit into a terrific opportunity for students to demonstrate their knowledge of erosion and develop…

  16. Mountain-Plains Curriculum.

    ERIC Educational Resources Information Center

    Mountain-Plains Education and Economic Development Program, Inc., Glasgow AFB, MT.

    The document lists the Mountain-Plains curriculum by job title (where applicable), including support courses. The curriculum areas covered are mathematics skills, communication skills, office education, lodging services, food services, marketing and distribution, welding support, automotive, small engines, career guidance, World of Work, health…

  17. Collision and mountain building

    NASA Astrophysics Data System (ADS)

    Trifonov, V. G.

    2016-01-01

    The spatial, chronological, and genetic relationships of recent (Late Alpine) collisions to mountain building are considered at three levels of scale: (i) in separate zones of the Arabian-Caucasus segment of the Alpine-Himalayan Orogenic Belt, (ii) throughout the central segment of this belt from the Alps to the Himalalayas, and (iii) in Central Asia and other mountain belts of continents. Three stages of mountain building are distinguished at all three levels. The first stage starts with widespread collision and similar plate interactions from the end of the Eocene to the middle Miocene and is expressed in the formation of uplifts, commonly no higher than the moderately elevated level in regions that concentrate deformations of transverse shortening induced by compression. The second short stage, which embraces the Pliocene-Quaternary and occasionally the end of the Miocene, differs in general, though differentiated in the value and intensification of vertical movements, when the height of mountains increases by 2-3 times. Elevations are spread over certain platform territories and even frameworks of rift zones. This is related not so much to the intensity of compression and shortening as to the compositional transformation of the upper mantle and the lower crust, leading to their decompaction. Comparison with the Hercynian and Caledonian orogenic stages shows that the second phase, predetermined by widespread collision, reflects a more important geodynamic event expressed in a change of the global plate interaction system and its deep-seated sources.

  18. Rocky Mountain Perspectives.

    ERIC Educational Resources Information Center

    Dutkiewicz, Jody Steiner, Ed.

    This publication features articles detailing the state of educational programs in the Rocky Mountain area. The articles address: 1) the impact of physical geography on culture, education, and lifestyle; 2) the education of migrant and/or agricultural workers and their children; 3) educational needs of children in rural areas; 4) outdoor education;…

  19. The Mountaineer Minority

    ERIC Educational Resources Information Center

    Egerton, John; Gaillard, Frye

    1974-01-01

    Discusses the new Appalachian movement, based on the assumption that mountain people are a distinct and maligned cultural minority; the people of Appalachia, white, black and red, have begun to strike back against the dam-builders, strip-miners, and others they say are gouging out the region's mineral resources by the cheapest means possible no…

  20. [Mountaineering and altitude sickness].

    PubMed

    Maggiorini, M

    2001-06-01

    Almost every second trekker or climber develops two to three symptoms of the high altitude illness after a rapid ascent (> 300 m/day) to an altitude above 4000 m. We distinguish two forms of high altitude illness, a cerebral form called acute mountain sickness and a pulmonary form called high altitude pulmonary edema. Essentially, acute mountain sickness is self-limiting and benign. Its symptoms are mild to moderate headache, loss of appetite, nausea, dizziness and insomnia. Nausea rarely progresses to vomiting, but if it does, this may anticipate a progression of the disease into the severe form of acute mountain sickness, called high altitude cerebral edema. Symptoms and signs of high altitude cerebral edema are severe headache, which is not relieved by acetaminophen, loss of movement coordination, ataxia and mental deterioration ending in coma. The mechanisms leading to acute mountain sickness are not very well understood; the loss of cerebral autoregulation and a vasogenic type of cerebral edema are being discussed. High altitude pulmonary edema presents in roughly twenty percent of the cases with mild symptoms of acute mountain sickness or even without any symptoms at all. Symptoms associated with high altitude pulmonary edema are incapacitating fatigue, chest tightness, dyspnoe at the minimal effort that advances to dyspnoe at rest and orthopnoe, and a dry non-productive cough that progresses to cough with pink frothy sputum due to hemoptysis. The hallmark of high altitude pulmonary edema is an exaggerated hypoxic pulmonary vasoconstriction. Successful prophylaxis and treatment of high altitude pulmonary edema using nifedipine, a pulmonary vasodilator, indicates that pulmonary hypertension is crucial for the development of high altitude pulmonary edema. The primary treatment of high altitude illness consists in improving hypoxemia and acclimatization. For prophylaxis a slow ascent at a rate of 300 m/day is recommended, if symptoms persist, acetazolamide at a

  1. Digital mountains: toward development and environment protection in mountain regions

    NASA Astrophysics Data System (ADS)

    Jiang, Xiaobo

    2007-06-01

    Former studies on mountain system are focused on the department or subject characters, i.e. different department and branches of learning carry out researches only for their individual purposes and with individual characters of the subject of interests. As a whole, their investigation is lacking of comprehensive study in combination with global environment. Ecological environment in mountain regions is vulnerable to the disturbance of human activities. Therefore, it is a key issue to coordinate economic development and environment protection in mountain regions. On the other hand, a lot of work is ongoing on mountain sciences, especially depending on the application of RS and GIS. Moreover, the development of the Digital Earth (DE) provides a clue to re-understand mountains. These are the background of the emergence of the Digital Mountains (DM). One of the purposes of the DM is integrating spatial related data and information about mountains. Moreover, the DM is a viewpoint and methodology of understanding and quantifying mountains holistically. The concept of the DM is that, the spatial and temporal data related to mountain regions are stored and managed in computers; moreover, manipulating, analyzing, modeling, simulating and sharing of the mountain information are implemented by utilizing technologies of RS, GIS, GPS, Geo-informatic Tupu, computer, virtual reality (VR), 3D simulation, massive storage, mutual operation and network communication. The DM aims at advancing mountain sciences and sustainable mountain development. The DM is used to providing information and method for coordinating the mountain regions development and environment protection. The fundamental work of the DM is the design of the scientific architecture. Furthermore, construct and develop massive databases of mountains are the important steps these days.

  2. Tectonic evolution of the central Brooks Range mountain front: Evidence from the Atigun Gorge region

    USGS Publications Warehouse

    Mull, C.G.; Glenn, R.K.; Adams, K.E.

    1997-01-01

    Atigun Gorge, at the northern front of the eastern Endicott Mountains, contains well-exposed rocks of the upper part of the Endicott Mountains allochthon and rocks of the structurally higher Picnic Creek or Ipnavik River allochthon. These allochthons contain rocks as young as Early Cretaceous (Valanginian) and are separated by a nearly vertical fault zone that contains exotic blocks of Triassic and Jurassic chert and silicified mudstone. Siliceous rocks of this type are not present in the Endicott Mountains allochthon but are characteristic of the Picnic Creek, Ipnavik River, and some of the other allochthons that structurally overlie the Endicott Mountains allochthon in the central and western Brooks Range. These exotic blocks, therefore indicate that structurally higher rocks of either the Picnic Creek or Ipnavik River allochthon were emplaced during the Early Cretaceous and are preserved along the northern flank of the eastern Endicott Mountains. The deformed thickness of this higher allochthon in the subsurface north of the mountains is unknown but probably exceeds 2 kilometers. Similar relations are mapped east of Atigun Gorge in an area of structural transition from the eastern Endicott Mountains into the northern Philip Smith Mountains, which are formed by the parautochthonous North Slope stratigraphic assemblage. The allochthonous rocks at the mountain front are regionally unconformably overlain by proximal Lower Cretaceous (Albian) foredeep conglomerate at the southern flank of the Colville basin, but at Atigun Gorge, the base of these deposits is interpreted as a possible back thrust at a triangle zone. Conglomerate clasts in the foredeep deposits are dominantly chert, mafic igneous rock, and other lithologies characteristic of the Picnic Creek and Ipnavik River allochthons and scattered clasts from the Endicott Mountains allochthon. The conglomerates show that the chert-rich allochthonous rocks and the Endicott Mountains allochthon were emplaced in the

  3. Geothermal systems of northern Nevada

    USGS Publications Warehouse

    Hose, Richard Kenneth; Taylor, Bruce Edward

    1974-01-01

    Hot springs are numerous and nearly uniformly distributed in northern Nevada. Most occur on the flanks of basins, along Basin and Range (late Miocene to Holocene) faults, while some occur in the inner parts of the basins. Surface temperatures of the springs range from slightly above ambient to, boiling; some springs are superheated. Maximum subsurface water temperatures calculated on the basis of quartz solubility range as high as 252?C, although most are below 190?C. Flows range from a trickle to several hundred liters per minute. The Nevada geothermal systems differ markedly from the power-producing system at The Geysers, Calif., and from those areas with a high potential, for power production (e.g., Yellowstone Park, Wyo.; Jemez Mountains, N. Mex.). These other systems are associated with Quaternary felsic volcanic rocks and probably derive their heat from cooling magma rather high in the crust. In northern Nevada, however, felsic volcanic rocks are virtually all older than 10 million years, and. analogous magmatic heat sources are, therefore, probably lacking. Nevada is part of an area of much higher average heat flow than the rest of the United States. In north-central Nevada, geothermal gradients are as great as 64?C per kilometer in bedrock and even higher in basin fill. The high gradients probably result from a combination of thin crust and high temperature upper mantle. We suggest that the geothermal systems of northern Nevada result from circulation of meteoric waters along Basin and Range faults and that their temperature chiefly depends upon (1) depth of circulation and (2) the geothermal gradient near the faults.

  4. Climate dominated topography in a tectonically active mountain range

    NASA Astrophysics Data System (ADS)

    Adams, B. A.; Ehlers, T. A.

    2015-12-01

    Tests of the interactions between tectonic and climate forcing on Earth's topography often focus on the concept of steady-state whereby processes of rock deformation and erosion are opposing and equal. However, when conditions change such as the climate or tectonic rock uplift, then surface processes act to restore the balance between rock deformation and erosion by adjusting topography. Most examples of canonical steady-state mountain ranges lie within the northern hemisphere, which underwent a radical change in the Quaternary due to the onset of widespread glaciation. The activity of glaciers changed erosion rates and topography in many of these mountain ranges, which likely violates steady-state assumptions. With new topographic analysis, and existing patterns of climate and rock uplift, we explore a mountain range previously considered to be in steady-state, the Olympic Mountains, USA. The broad spatial trend in channel steepness values suggests that the locus of high rock uplift rates is coincident with the rugged range core, in a similar position as high temperature and pressure lithologies, but not in the low lying foothills as has been previously suggested by low-temperature thermochronometry. The details of our analysis suggest the dominant topographic signal in the Olympic Mountains is a spatial, and likely temporal, variation in erosional efficiency dictated by orographic precipitation, and Pleistocene glacier ELA patterns. We demonstrate the same topographic effects are recorded in the basin hypsometries of other Cenozoic mountain ranges around the world. The significant glacial overprint on topography makes the argument of mountain range steadiness untenable in significantly glaciated settings. Furthermore, our results suggest that most glaciated Cenozoic ranges are likely still in a mode of readjustment as fluvial systems change topography and erosion rates to equilibrate with rock uplift rates.

  5. Climate Change Has Cascading Ecological Effects on Mountain Ecosystems

    NASA Astrophysics Data System (ADS)

    Fagre, D. B.

    2007-12-01

    Evidence that ecosystems of the Northern Rocky Mountains are responding to climate change abounds. Alpine glaciers, as iconic landscape features, are disappearing rapidly with some glaciers losing one half of their area in five years. A model developed in the 1990s to predict future rates of melt has proved too conservative when compared to recent measurements. The largest glaciers in Glacier National Park are almost 10 years ahead of schedule in their retreat. The cascading ecological effects of losing glaciers in high-elevation watersheds includes shifts in distribution and dominance of temperature-sensitive stream macroinvertebrates as stream volume dwindles (or disappears) in later summer months and water temperatures increase. Critical spawning areas for threatened bull trout (Salvelinus confluentus) will be lost without the consistent supply of cold water that melting snow and ice provide and raise management questions regarding the efficacy of recovery efforts. Snowpacks are documented as becoming smaller and melting earlier in the spring, facilitating the invasion of subalpine meadows by trees and reducing habitat for current alpine wildlife. Even vital ecosystem disturbances, such as periodic snow avalanches that clear mountain slope forests, have been shown by tree-ring studies to be responsive to climatic trends and are likely to become less prevalent. Monitoring of high-elevation mountain environments is difficult and has largely been opportunistic despite the fact that these areas have experienced three times the temperature increases over the past century when compared to lowland environments. A system of alpine observatories is sorely needed. Tighter integration of mountains studies, and comparisons among diverse mountain systems of the western U.S. has been initiated by the USGS-sponsored Western Mountain Initiative and the Consortium for Integrated Climate Research in Western Mountains to begin addressing this need.

  6. Yucca Mountain Milestone

    SciTech Connect

    Hunt, Rod

    1997-06-09

    The Department of Energy project to determine if the Yucca Mountain site in Nevada is suitable for geologic disposal of high-level nuclear waste reached a major milestone in late April when a 25-foot-diameter tunnel boring machine ``holed through'' completing a five-mile-long, horseshoe-shaped excavation through the mountain. When the cutting-head of the giant machine broke through to daylight at the tunnel's south portal, it ended a 2 1/2-year excavation through the mountain that was completed ahead of schedule and with an outstanding safety record. Video of the event was transmitted live by satellite to Washington, DC, where it was watched by Secretary of Energy Frederico Pena and other high-level DOE officials, signifying the importance of the project's mission to find a repository for high-level nuclear waste and spent nuclear fuel produced by nuclear power plants. This critical undertaking is being performed by DOE's Office of Civilian Radioactive Waste Management (OCRWM). The tunnel is the major feature of the Exploratory Studies Facility (ESF), which serves as an underground laboratory for engineers and scientists to help determine if Yucca Mountain is suitable to serve as a repository for the safe disposal of high-level nuclear waste. Morrison Knudsen's Environmental/Government Group is providing design and construction-management services on the project. The MK team is performing final design for the ESF and viability assessment design for the underground waste repository that will be built only if the site is found suitable for such a mission. In fact, if at anytime during the ESF phase, the site is found unsuitable, the studies will be stopped and the site restored to its natural state.

  7. Correlation of the Klamath Mountains and Sierra Nevada

    USGS Publications Warehouse

    Irwin, William P.

    2003-01-01

    This report graphically portrays the broadly parallel tectonic development of the Klamath Mountains and Sierra Nevada from early Paleozoic to Early Cretaceous time. It is dedicated to J.S. Diller of the U.S. Geological Survey who, during his pioneer field studies a century ago, recognized significant similarities between these two important provinces. The report is based mainly on the numerous published reports of the field and laboratory studies by various geologists and students during the last century, and to a lesser extent on my own field work which has been substantial in the Klamath Mountains but minimal in the Sierra Nevada. For brevity, required by the format of this report, little of the extensive literature pertaining to these two provinces is referenced. This report is preliminary in nature and was prepared as an aid to further study of the tectonic relations between the Klamath Mountains and Sierra Nevada. This report consists of two sheets: Sheet 1, Map showing accreted terranes and plutons of the Klamath Mountains and Sierra Nevada, and Sheet 2, Successive accretionary episodes of the Klamath mountains and northern part of Sierra Nevada, showing related plutonic, volcanic, and metamorphic events. The map on Sheet 1 was compiled and modified from two Open-File maps (Irwin and Wooden, 1999 and 2001) which had been compiled and modified mainly from Jennings (1977), Harwood (1992), Irwin (1994), Jayko (1988), Graymer and Jones (1994), Edelman and Sharp (1989), Schweickert and others (1999), Saucedo and Wagner(1992), Saleeby and Sharp (1980), Wagner and others (1981), and various other sources. For detailed lists of the sources for the isotopic age data used in Sheets 1 and 2, see Irwin and Wooden (1999 and 2001). On Sheet 2, the accretionary episodes are shown sequentially from left to right in two tiers of figures. Episodes for the Klamath Mountains are in the upper tier; correlative episodes of the Sierra Nevada are directly below in the lower tier

  8. Patient-centred mountain medicine.

    PubMed

    Szawarski, Piotr; Hillebrandt, David

    2016-08-01

    Venturing into the mountains, doctors have accompanied expeditions to provide routine care to the teams, undertake research and occasionally take on a rescue role. The role of doctors practicing mountain medicine is evolving. Public health issues involving concepts of health and safety have become necessary with the coming of commercial and youth expeditions. Increasingly individuals with a disability or a medical diagnosis choose to ascend to high altitudes. Doctors become involved in assessment of risk and providing advice for such individuals. The field of mountain medicine is perhaps unique in that acceptance of risk is part of the ethos of climbing and adventure. The pursuit of mountaineering goals may represent the ultimate conquest of a disability. Knowledge of mountain environment is essential in facilitating mountain ascents for those who choose to undertake them, in spite of a disability or medical condition. PMID:27234206

  9. Observing globular cluster RR Lyraes with the BYU West Mountain Observatory

    NASA Astrophysics Data System (ADS)

    Jeffery, E. J.; Joner, M. D.; Walton, R. S.

    2016-05-01

    We have utilized the 0.9-meter telescope of the Brigham Young University West Mountain Observatory to secure data on six northern hemi- sphere globular clusters. Here we present observations of RR Lyrae stars located in these clusters. We compare light curves produced using both DAOPHOT and ISIS software packages. Light curve fitting is done with FITLC.

  10. Bordetella bronchiseptica associated with pulmonary disease in mountain voles (Microtus montanus)

    USGS Publications Warehouse

    Jensen, W.I.; Duncan, R.M.

    1980-01-01

    Bordetella bronchiseptica was isolated from the lungs of all of six mountain voles (Microtus montanus) found dead or dying of pulmonary infection near the Bear River Research Station in northern Utah in January, 1973. The possibility of concomitant viral or mycoplasmal infection was not ruled out.

  11. Intraspecific phylogeography of red squirrels (Tamiasciurus hudsonicus) in the central Rocky Mountain region of North America.

    PubMed

    Wilson, Gregory M; Den Bussche, Ronald A; McBee, Karen; Johnson, Lacrecia A; Jones, Cheri A

    2005-11-01

    We used variation in a portion of the mitochondrial DNA control region to examine phylogeography of Tamiasciurus hudsonicus, a boreal-adapted small mammal in the central Rocky Mountain region. AMOVA revealed that 65.66% of genetic diversity was attributable to variation within populations, 16.93% to variation among populations on different mountain ranges, and 17.41% to variation among populations within mountain ranges. Nested clade analysis revealed two major clades that likely diverged in allopatry during the Pleistocene: a southern clade from southern Colorado and a northern clade comprising northern Colorado, Wyoming, eastern Utah, and eastern Idaho. Historically restricted gene flow as a result of geographic barriers was indicated between populations on opposite sides of the Green River and Wyoming Basin and among populations in eastern Wyoming. In some instances genetic structure indicated isolation by distance. PMID:16247688

  12. Flash floods in the Tatra Mountain streams: frequency and triggers.

    PubMed

    Ballesteros-Cánovas, J A; Czajka, B; Janecka, K; Lempa, M; Kaczka, R J; Stoffel, M

    2015-04-01

    Flash floods represent a frequently recurring natural phenomenon in the Tatra Mountains. On the northern slopes of the mountain chain, located in Poland, ongoing and expected future changes in climate are thought to further increase the adverse impacts of flash floods. Despite the repeat occurrence of major floods in the densely populated foothills of the Polish Tatras, the headwaters have been characterized by a surprising lack of data, such that any analysis of process variability or hydrometeorological triggers has been largely hampered so far. In this study, dendrogeomorphic techniques have been employed in four poorly-gauged torrential streams of the northern slope of the Tatra Mountains to reconstruct temporal and spatial patterns of past events. Using more than 1100 increment cores of trees injured by past flash floods, we reconstruct 47 events covering the last 148 years and discuss synoptic situations leading to the triggering of flash floods with the existing meteorological and flow gauge data. Tree-ring analyses have allowed highlighting the seasonality of events, providing new insights about potential hydrometeorological triggers as well as a differentiating flash flood activity between catchments. Results of this study could be useful to design future strategies to deal with flash flood risks at the foothills of the Polish Tatras and in the Vistula River catchment. PMID:25594906

  13. Major-ion chemistry of the Rocky Mountain snowpack, USA

    USGS Publications Warehouse

    Turk, J.T.; Taylor, H.E.; Ingersoll, G.P.; Tonnessen, K.A.; Clow, D.W.; Mast, M.A.; Campbell, D.H.; Melack, J.M.

    2001-01-01

    During 1993-97, samples of the full depth of the Rocky Mountain snowpack were collected at 52 sites from northern New Mexico to Montana and analyzed for major-ion concentrations. Concentrations of acidity, sulfate, nitrate, and calcium increased from north to south along the mountain range. In the northern part of the study area, acidity was most correlated (negatively) with calcium. Acidity was strongly correlated (positively) with nitrate and sulfate in the southern part and for the entire network. Acidity in the south exceeded the maximum acidity measured in snowpack of the Sierra Nevada and Cascade Mountains. Principal component analysis indicates three solute associations we characterize as: (1) acid (acidity, sulfate, and nitrate), (2) soil (calcium, magnesium, and potassium), and (3) salt (sodium, chloride, and ammonium). Concentrations of acid solutes in the snowpack are similar to concentrations in nearby wetfall collectors, whereas, concentrations of soil solutes are much higher in the snowpack than in wetfall. Thus, dryfall of acid solutes during the snow season is negligible, as is gypsum from soils. Snowpack sampling offers a cost-effective complement to sampling of wetfall in areas where wetfall is difficult to sample and where the snowpack accumulates throughout the winter. Copyright ?? 2001 .

  14. Altitude, Acute Mountain Sickness and Headache

    MedlinePlus

    ... Mountain Sickness, and Headache Print Email Altitude, Acute Mountain Sickness, and Headache ACHE Newsletter Sign up for ... entering your e-mail address below. Altitude, Acute Mountain Sickness, and Headache David W. Dodick, MD, FAHS, ...

  15. Does mountain permafrost in Mongolia control water availability?

    NASA Astrophysics Data System (ADS)

    Menzel, Lucas; Kopp, Benjamin; Munkhjargal, Munkhdavaa

    2016-04-01

    In semi-arid Mongolia, continuous and discontinuous permafrost covers wide parts of the mountains, especially in the northwest of the country. Long-term analysis of annual discharge from rivers draining the mountainous parts shows high temporal variability, with some evidence of decreasing trends, accompanied by decreased intra-annual variability. Investigations show that annual precipitation features small changes while annual air temperature significantly increased over the last decades, with warming rates clearly outranging the global average. Widespread and drastic changes in land cover through forest fires in northern Mongolia might have an additional impact on water retention and the stability of permafrost. Hence, there is concern about an increased degradation of mountain permafrost and a possible impact on river discharge and water availability. Decreased water availability from the mountains would have strong socio-economic implications for the population living in the steppe belt downstream the mountains. Therefore, a monitoring program has been conducted in northern Mongolia that aims to improve the understanding of how climate change and forest fires are influencing mountain permafrost and water resources. The study region, Sugnugur valley, is located about 100 km north of Ulaanbaatar and includes the transition belt between the steppe, the boreal zone and the alpine tundra of the Khentii Mountains. Extensive measurements of soil temperatures, soil moisture, discharge and climatic parameters have been carried out along transects which stretch across the Sugnugur river valley and include steppe, boreal forest as well as burnt forest. First results indicate that the environmental conditions show drastic changes after forest fire, with reduced water retention in the headwaters. After forest fires, changing runoff processes above the permafrost table have been observed, where water drains rapidly along preferential flow paths. This eventually leads to

  16. SP mountain data analysis

    NASA Technical Reports Server (NTRS)

    Rawson, R. F.; Hamilton, R. E.; Liskow, C. L.; Dias, A. R.; Jackson, P. L.

    1981-01-01

    An analysis of synthetic aperture radar data of SP Mountain was undertaken to demonstrate the use of digital image processing techniques to aid in geologic interpretation of SAR data. These data were collected with the ERIM X- and L-band airborne SAR using like- and cross-polarizations. The resulting signal films were used to produce computer compatible tapes, from which four-channel imagery was generated. Slant range-to-ground range and range-azimuth-scale corrections were made in order to facilitate image registration; intensity corrections were also made. Manual interpretation of the imagery showed that L-band represented the geology of the area better than X-band. Several differences between the various images were also noted. Further digital analysis of the corrected data was done for enhancement purposes. This analysis included application of an MSS differencing routine and development of a routine for removal of relief displacement. It was found that accurate registration of the SAR channels is critical to the effectiveness of the differencing routine. Use of the relief displacement algorithm on the SP Mountain data demonstrated the feasibility of the technique.

  17. Petrogenesis of the Late Cretaceous northern Alberta kimberlite province

    NASA Astrophysics Data System (ADS)

    Eccles, D. Roy; Heaman, Larry M.; Luth, Robert W.; Creaser, Robert A.

    2004-09-01

    At present, 48 Late Cretaceous (ca. 70-88 Ma) kimberlitic pipes have been discovered in three separate areas of the northern Alberta: the Mountain Lake cluster, the Buffalo Head Hills field and the Birch Mountains field. The regions can be distinguished from one another by their non-archetypal kimberlite signature (Mountain Lake) or, in the case of kimberlite fields, primitive (Buffalo Head Hills) to evolved (Birch Mountains) magmatic signatures. The dominant process of magmatic differentiation is crystal fractionation and accumulation of olivine, which acts as the main criteria to distinguish between primitive and evolved Group I-type kimberlite fields in the northern Alberta. This is important from the viewpoint of diamond exploration because the majority (about 80%) of the more primitive Buffalo Head Hills kimberlites are diamondiferous, whereas the more evolved Birch Mountains pipes are barren of diamonds for the most part. Petrographically, the Buffalo Head Hills samples are distinct from the Birch Mountains samples in that they contain less carbonate, have a smaller modal abundance of late-stage minerals such as phlogopite and ilmenite, and have a higher amount of fresh, coarse macrocrystal (>0.5 mm) olivine. Consequently, samples from the Buffalo Head Hills have the highest values of MgO, Cr and Ni, and have chemistries similar to those of primitive hypabyssal kimberlite in the Northwest Territories. Based on whole-rock isotopic data, the Buffalo Head Hills K6 kimberlite has 87Sr/ 86Sr and ɛNd values similar to those of South African Group I kimberlites, whereas the Birch Mountains Legend and Phoenix kimberlites have similar ɛNd values (between 0 and +1.9), but distinctly higher 87Sr/ 86Sr values (0.7051-0.7063). The lack of whole-rock geochemical overlap between kimberlite and the freshest, least contaminated Mountain Lake South pipe rocks reflects significant mineralogical differences and Mountain Lake is similar geochemically to olivine alkali basalt

  18. Site testing for the VLT in Northern Chile

    NASA Astrophysics Data System (ADS)

    Woltjer, L.

    The European Southern Observatory (ESO) will need sites for three telescopes. The telescopes considered include the 3.5 m New Technology Telescope to be completed in 1987, the 15 m Swedish-ESO mm/submm telescope, and the Very Large Telescope (VLT). The first two telescopes will probably be placed on La Silla. However, because of humidity considerations, a later transfer of the 15 m mm/submm telescope to a drier site appears possible. The main reason for conducting a new site survey is related to the VLT. Possible areas for establishing an observatory in the Southern Hemisphere are examined, taking into account Northern Chile. Attention is given to an area south of Antofagasta, mountains west of the Salar de Punta Negra, mountains between San Pedro de Atacama and El Tatio, mountains east of La Silla, problems regarding the observation of faint objects, water vapor content, and difficulties due to wind.

  19. 13. TREES ALONG LATERAL SEGMENT AT THE NORTHERN END OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. TREES ALONG LATERAL SEGMENT AT THE NORTHERN END OF LAKE LADORA. - Highline Canal, Sand Creek Lateral, Beginning at intersection of Peoria Street & Highline Canal in Arapahoe County (City of Aurora), Sand Creek lateral Extends 15 miles Northerly through Araphoe County, City & County of Denver, & Adams County to its end point, approximately 1/4 mile Southest of intersectioin of D Street & Ninth Avenue in Adams County (Rocky Mountain Arsenal, Commerce City Vicinity), Commerce City, Adams County, CO

  20. YUCCA MOUNTAIN PROJECT - A BRIEFING --

    SciTech Connect

    NA

    2003-08-05

    This report has the following articles: Nuclear waste--a long-term national problem; Spent nuclear fuel; High-level radioactive waste; Radioactivity and the environment; Current storage methods; Disposal options; U.S. policy on nuclear waste; The focus on Yucca Mountain; The purpose and scope of the Yucca Mountain Project; The approach for permanently disposing of waste; The scientific studies at Yucca Mountain; The proposed design for a repository at Yucca Mountain; Natural and engineered barriers would work together to isolate waste; Meticulous science and technology to protect people and the environment; Licensing a repository; Transporting waste to a permanent repository; The Environmental Impact Statement for a repository; Current status of the Yucca Mountain Project; and Further information available on the Internet.

  1. Extrusional Tectonics over Plate Corner: an Example in Northern Taiwan

    NASA Astrophysics Data System (ADS)

    Lu, Chia-Yu; Lee, Jian-Cheng; Li, Zhinuo; Lee, Ching-An; Yeh, Chia-Hung

    2016-04-01

    In northern Taiwan, contraction, transcurrent shearing, block rotation and extension are four essential tectonic deformation mechanisms involved in the progressive deformation of this arcuate collision mountain belt. The neotectonic evolution of the Taiwan mountain belt is mainly controlled not only by the oblique convergence between the Eurasian plate and the Philippine Sea plate but also the corner shape of the plate boundary. Based on field observations and analyses, and taking geophysical data (mostly GPS) and experimental modelling into account, we interpret the curved belt of northern Taiwan as a result of of contractional deformation (with compression, thrust-sheet stacking & folding, back thrust duplex & back folding) that induced vertical extrusion, combined with increasing transcurrent & rotational deformation (with transcurrent faulting, bookshelf-type strike-slip faulting and block rotation) that induced transcurrent/rotational extrusion and extension deformation which in turn induced extensional extrusion. As a consequence, a special type of extrusional folds was formed in association with contractional, transcurrent & rotational and extensional extrusions subsequently. The extrusional tectonics in northern Taiwan reflect a single, albeit complicated, regional pattern of deformation. The crescent-shaped mountain belt of Northeastern Taiwan develops in response to oblique indentation by an asymmetric wedge indenter, retreat of Ryukyu trench and opening of the Okinawa trough.

  2. Geology at Yucca Mountain

    SciTech Connect

    1993-05-01

    Both advocates and critics disagree on the significance and interpretation of critical geological features which bear on the safety and suitability of Yucca Mountain as a site for the construction of a high-level radioactive waste repository. Critics believe that there is sufficient geological evidence to rule the site unsuitable for further investigation. Some advocates claim that there is insufficient data and that investigations are incomplete, while others claim that the site is free of major obstacles. We have expanded our efforts to include both the critical evaluations of existing geological and geochemical data and the collection of field data and samples for the purpose of preparing scientific papers for submittal to journals. Summaries of the critical reviews are presented in this paper.

  3. Iron Mountain Electromagnetic Results

    SciTech Connect

    Gail Heath

    2012-07-01

    Iron Mountain Mine is located seventeen miles northwest of Redding, CA. After the completion of mining in early 1960s, the mine workings have been exposed to environmental elements which have resulted in degradation in water quality in the surrounding water sheds. In 1985, the EPA plugged ore stoops in many of the accessible mine drifts in an attempt to restrict water flow through the mine workings. During this process little data was gathered on the orientation of the stoops and construction of the plugs. During the last 25 years, plugs have begun to deteriorate and allow acidic waters from the upper workings to flow out of the mine. A team from Idaho National Laboratory (INL) performed geophysical surveys on a single mine drift and 3 concrete plugs. The project goal was to evaluate several geophysical methods to determine competence of the concrete plugs and orientation of the stopes.

  4. ESTIMATES OF CLOUD WATER DEPOSITION AT MOUNTAIN DEPOSITION AT MOUNTAIN ACID DEPOSITION PROGRAM SITES IN THE APPALACHIAN MOUNTAINS

    EPA Science Inventory

    Cloud water deposition was estimated at three high elevation sites in the Appalachian Mountains of the eastern United States (Whiteface Mountain, NY, Whitetop Mountain, VA, and Clingrnan's Dome, TN) from 1994 through 1999 as part of the Mountain Acid Deposition Program (MADPro). ...

  5. Archaeocyathan buildups within an entirely siliciclastic succession: New discovery in the Toyonian Lalun Formation of northern Iran, the Proto-Paleotethys passive margin of northern Gondwana

    NASA Astrophysics Data System (ADS)

    Lasemi, Yaghoob; Amin-Rasouli, Hadi

    2007-10-01

    Meter-scale buildups constructed exclusively by archaeocyaths have been recognized within the uppermost Lower Cambrian siliciclastic succession of Eastern Alborz in northern Iran. They are the only known Toyonian reefs in Iran and adjacent countries and occur in the lower part of the Shale unit of the Lalun Formation. The reefs are of limited lateral extent, reach a maximum thickness of 2.5 m and consist of several reef complexes containing cabbage- or sack-shaped buildups surrounded by well-bedded, colored shale. Each reef complex in the main reef zone consists of meter-scale individual and kalyptrate (compound) buildups that are overgrown by laminated stromatolite. The individual buildups are 12 to 75 cm thick and 5 to 50 cm in diameter, but the compound buildups are up to 2 m thick and their diameter ranges from 75 to 120 cm. In contrast to most Lower Cambrian reefs, these compound buildups demonstrate a complete ecological succession including pioneer and climax phases. Archaeocyaths in the buildups are solitary and colonial types showing great diversity of growth forms, with vase-, bowl- and cup-shaped and cylindrical forms present. The cups range from less than 1 mm to 1.5 cm in diameter and are up to 4 cm tall in the majority of the skeletons, but they may reach up to 4 cm in diameter in the massive colonial forms or in the branching forms of the upper outer part of the compound bioherms. The limited lateral extent of the reef horizons, and lateral facies changes in the colored shale toward various reefs supports deposition in drowned tidal channels in an estuarine depositional environment. A change of the individual bioherms to larger compound buildups suggests lateral depth variation of the tidal channels. Partial infilling of the primary inter-biohermal cavities by large reef clasts and cross-laminated siltstone to very fine sandstone suggests occasional disturbances by storms and periodic influx of coarse siliciclastics. In striking contrast to other

  6. Glacial reorganization of topography in a tectonically active mountain range

    NASA Astrophysics Data System (ADS)

    Adams, Byron; Ehlers, Todd

    2016-04-01

    Tests of the interactions between tectonic and climate forcing on Earth's topography often focus on the concept of steady-state whereby processes of rock deformation and erosion are opposing and equal. However, when conditions change such as the climate or tectonic rock uplift, then surface processes act to restore the balance between rock deformation and erosion by adjusting topography. Most examples of canonical steady-state mountain ranges lie within the northern hemisphere, which underwent a radical change in the Quaternary due to the onset of widespread glaciation. The activity of glaciers changed erosion rates and topography in many of these mountain ranges, which likely violates steady-state assumptions. With new topographic analysis, and existing patterns of climate and rock uplift, we explore a mountain range previously considered to be in steady-state, the Olympic Mountains, USA. The details of our analysis suggest the dominant topographic signal in the Olympic Mountains is a spatial, and likely temporal, variation in erosional efficiency dictated by orographic precipitation, and Pleistocene glacier ELA patterns, and not tectonic rock uplift rates. Alpine glaciers drastically altered the relief structure of the Olympic Mountains. The details of these relief changes are recorded in channel profiles as overdeepenings, reduced slopes, and associated knickpoints. We find the position of these relief changes within the orogen is dependent on the position of the Pleistocene ELA. While alpine glaciers overdeepened valleys in regions near the Pleistocene ELA (which has a tendency to increase relief), headward erosion of west and north flowing glacier systems captured significant area from opposing systems and caused drainage divide lowering. This divide lowering reduced relief throughout the range. We demonstrate similar topographic effects recorded in the basin hypsometries of other Cenozoic mountain ranges around the world. The significant glacial overprint on

  7. Fire and vegetation history of the Jemez Mountains

    USGS Publications Warehouse

    Allen, Craig D.

    2001-01-01

    Historic patterns of fire occurrence and vegetation change in the Jemez Mountains of northern New Mexico have been described in detail by using multiple lines of evidence. Data sources include old aerial and ground-based photographs, historic records, charcoal deposits from bogs, fire-scarred trees (Figure 1), tree-ring reconstructions of precipitation, and field sampling of vegetation and soils. The forests and woodlands that cloak the Southwestern uplands provide the most extensive and detailed regional-scale network of fire history data available in the world (Swetnam and Baisan 1996, Swetnam et al. 1999, Allen 2002).

  8. 27 CFR 9.80 - York Mountain.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false York Mountain. 9.80... Mountain. (a) Name. The name of the viticultural area described in this section is “York Mountain.” (b) Approved map. The approved map for the York Mountain viticultural area is the U.S.G.S. map entitled...

  9. 27 CFR 9.55 - Bell Mountain.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Bell Mountain. 9.55... Mountain. (a) Name. The name of the viticultural area described in this section is “Bell Mountain.” (b) Approved map. The appropriate map for determining the boundaries of the Bell Mountain viticultural area...

  10. 27 CFR 9.167 - Red Mountain

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Red Mountain 9.167 Section... Mountain (a) Name. The name of the viticultural area described in this section is “Red Mountain.” (b) Approved maps. The appropriate map for determining the boundaries of the Red Mountain viticultural area...

  11. 27 CFR 9.55 - Bell Mountain.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Bell Mountain. 9.55... Mountain. (a) Name. The name of the viticultural area described in this section is “Bell Mountain.” (b) Approved map. The appropriate map for determining the boundaries of the Bell Mountain viticultural area...

  12. 27 CFR 9.55 - Bell Mountain.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Bell Mountain. 9.55... Mountain. (a) Name. The name of the viticultural area described in this section is “Bell Mountain.” (b) Approved map. The appropriate map for determining the boundaries of the Bell Mountain viticultural area...

  13. 27 CFR 9.55 - Bell Mountain.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Bell Mountain. 9.55... Mountain. (a) Name. The name of the viticultural area described in this section is “Bell Mountain.” (b) Approved map. The appropriate map for determining the boundaries of the Bell Mountain viticultural area...

  14. 27 CFR 9.167 - Red Mountain

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Red Mountain 9.167 Section... Mountain (a) Name. The name of the viticultural area described in this section is “Red Mountain.” (b) Approved maps. The appropriate map for determining the boundaries of the Red Mountain viticultural area...

  15. 27 CFR 9.80 - York Mountain.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false York Mountain. 9.80... Mountain. (a) Name. The name of the viticultural area described in this section is “York Mountain.” (b) Approved map. The approved map for the York Mountain viticultural area is the U.S.G.S. map entitled...

  16. 27 CFR 9.167 - Red Mountain

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Red Mountain 9.167 Section... Mountain (a) Name. The name of the viticultural area described in this section is “Red Mountain.” (b) Approved maps. The appropriate map for determining the boundaries of the Red Mountain viticultural area...

  17. 27 CFR 9.80 - York Mountain.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false York Mountain. 9.80... Mountain. (a) Name. The name of the viticultural area described in this section is “York Mountain.” (b) Approved map. The approved map for the York Mountain viticultural area is the U.S.G.S. map entitled...

  18. 27 CFR 9.55 - Bell Mountain.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Bell Mountain. 9.55... Mountain. (a) Name. The name of the viticultural area described in this section is “Bell Mountain.” (b) Approved map. The appropriate map for determining the boundaries of the Bell Mountain viticultural area...

  19. 27 CFR 9.80 - York Mountain.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false York Mountain. 9.80... Mountain. (a) Name. The name of the viticultural area described in this section is “York Mountain.” (b) Approved map. The approved map for the York Mountain viticultural area is the U.S.G.S. map entitled...

  20. 27 CFR 9.167 - Red Mountain

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Red Mountain 9.167 Section... Mountain (a) Name. The name of the viticultural area described in this section is “Red Mountain.” (b) Approved maps. The appropriate map for determining the boundaries of the Red Mountain viticultural area...

  1. 27 CFR 9.167 - Red Mountain

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Red Mountain 9.167 Section... Mountain (a) Name. The name of the viticultural area described in this section is “Red Mountain.” (b) Approved maps. The appropriate map for determining the boundaries of the Red Mountain viticultural area...

  2. 27 CFR 9.80 - York Mountain.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false York Mountain. 9.80... Mountain. (a) Name. The name of the viticultural area described in this section is “York Mountain.” (b) Approved map. The approved map for the York Mountain viticultural area is the U.S.G.S. map entitled...

  3. How the mountain pine beetle (Dendroctonus ponderosae) breached the Canadian Rocky Mountains.

    PubMed

    Janes, Jasmine K; Li, Yisu; Keeling, Christopher I; Yuen, Macaire M S; Boone, Celia K; Cooke, Janice E K; Bohlmann, Joerg; Huber, Dezene P W; Murray, Brent W; Coltman, David W; Sperling, Felix A H

    2014-07-01

    The mountain pine beetle (MPB; Dendroctonus ponderosae Hopkins), a major pine forest pest native to western North America, has extended its range north and eastward during an ongoing outbreak. Determining how the MPB has expanded its range to breach putative barriers, whether physical (nonforested prairie and high elevation of the Rocky Mountains) or climatic (extreme continental climate where temperatures can be below -40 °C), may contribute to our general understanding of range changes as well as management of the current epidemic. Here, we use a panel of 1,536 single nucleotide polymorphisms (SNPs) to assess population genetic structure, connectivity, and signals of selection within this MPB range expansion. Biallelic SNPs in MPB from southwestern Canada revealed higher genetic differentiation and lower genetic connectivity than in the northern part of its range. A total of 208 unique SNPs were identified using different outlier detection tests, of which 32 returned annotations for products with putative functions in cholesterol synthesis, actin filament contraction, and membrane transport. We suggest that MPB has been able to spread beyond its previous range by adjusting its cellular and metabolic functions, with genome scale differentiation enabling populations to better withstand cooler climates and facilitate longer dispersal distances. Our study is the first to assess landscape-wide selective adaptation in an insect. We have shown that interrogation of genomic resources can identify shifts in genetic diversity and putative adaptive signals in this forest pest species. PMID:24803641

  4. How the Mountain Pine Beetle (Dendroctonus ponderosae) Breached the Canadian Rocky Mountains

    PubMed Central

    Janes, Jasmine K.; Li, Yisu; Keeling, Christopher I.; Yuen, Macaire M.S.; Boone, Celia K.; Cooke, Janice E.K.; Bohlmann, Joerg; Huber, Dezene P.W.; Murray, Brent W.; Coltman, David W.; Sperling, Felix A.H.

    2014-01-01

    The mountain pine beetle (MPB; Dendroctonus ponderosae Hopkins), a major pine forest pest native to western North America, has extended its range north and eastward during an ongoing outbreak. Determining how the MPB has expanded its range to breach putative barriers, whether physical (nonforested prairie and high elevation of the Rocky Mountains) or climatic (extreme continental climate where temperatures can be below −40 °C), may contribute to our general understanding of range changes as well as management of the current epidemic. Here, we use a panel of 1,536 single nucleotide polymorphisms (SNPs) to assess population genetic structure, connectivity, and signals of selection within this MPB range expansion. Biallelic SNPs in MPB from southwestern Canada revealed higher genetic differentiation and lower genetic connectivity than in the northern part of its range. A total of 208 unique SNPs were identified using different outlier detection tests, of which 32 returned annotations for products with putative functions in cholesterol synthesis, actin filament contraction, and membrane transport. We suggest that MPB has been able to spread beyond its previous range by adjusting its cellular and metabolic functions, with genome scale differentiation enabling populations to better withstand cooler climates and facilitate longer dispersal distances. Our study is the first to assess landscape-wide selective adaptation in an insect. We have shown that interrogation of genomic resources can identify shifts in genetic diversity and putative adaptive signals in this forest pest species. PMID:24803641

  5. Genetics Home Reference: Northern epilepsy

    MedlinePlus

    ... Understand Genetics Home Health Conditions Northern epilepsy Northern epilepsy Enable Javascript to view the expand/collapse boxes. Download PDF Open All Close All Description Northern epilepsy is a genetic condition that causes recurrent seizures ( ...

  6. Structural style of east flank of Bighorn Mountains, Johnson and Sheridan Counties, Wyoming

    SciTech Connect

    Furner, R.B. )

    1989-09-01

    The 70 mi-long portion of the east flank of the Bighorn Mountains, between Sheridan and Mayoworth, Wyoming, is structurally divisible into three distinct segments - northern, central, and southern - each distinguished by a dominant sense of vergence and structural style. The northern segment displays southwest-verging reverse faults and associated folds, indicating tectonic transport out of the Powder River basin and onto the mountain flank. The central segment displays northeast and east-northeast-verging reverse faults and associated folds, indicating tectonic transport of the mountain flank over the Powder River basin. Seismic and drill-hole data indicate most of these reverse faults dip to the southwest and west-southwest at angles of 35{degree} or less. The southern segment displays west-southwest-verging reverse faults and associated folds, again indicating tectonic transport out of the Powder River basin and onto the mountain flank. All major structures identified within the area of investigation are basement involved, and the geometry of the rocks supports the concept that the mountain flank deformed under the influence of northeast-southwest-directed horizontal compression rather than vertically oriented block uplift.

  7. Long-range atmospheric transport and the distribution of polycyclic aromatic hydrocarbons in Changbai Mountain.

    PubMed

    Zhao, Xiangai; Kim, Seung-Kyu; Zhu, Weihong; Kannan, Narayanan; Li, Donghao

    2015-01-01

    The Changbai (also known as "Baekdu") Mountain, on the border between China and North Korea, is the highest mountain (2750 m) in northeastern China. Recently, this mountain region has experienced a dramatic increase in air pollution, not only because of increasing volumes of tourism-derived traffic but also because of the long-range transport of polluted westerly winds passing through major industrial and urban cities in the eastern region of China. To assess the relative importance of the two sources of pollution, 16 polycyclic aromatic hydrocarbons (PAHs) as model substances were determined in the mountain soil. A total of 32 soil samples were collected from different sides of the mountain at different latitudes between July and August of 2009. The ∑PAH concentrations were within the range 38.5-190.1 ng g(-1) on the northern side, 117.7-443.6 ng g(-1) on the southern side, and 75.3-437.3 ng g(-1) on the western side. A progressive increase in the level of ∑PAHs with latitude was observed on the southern and western sides that face the westerly wind with abundant precipitation. However, a similar concentration gradient was not observed on the northern side that receives less rain and is on the leeward direction of the wind. The high-molecular-weight PAH compounds were predominant in the soils on the southern and western sides, while low-molecular-weight PAHs dominated the northern side soils. These findings show that the distribution of PAHs in the mountain soil is strongly influenced by the atmospheric long-range transport and cold trapping. PMID:25036943

  8. Development of foreland basins around western Sichuan basin, and implications for mountain building in eastern Tibet

    NASA Astrophysics Data System (ADS)

    Chen, S.; Liu, M.

    2014-12-01

    The Sichuan basin is surrounded by the Tibetan Plateau to the west, and the Michang Shan and Daba Shan mountains to the north and northwest. Foreland basins have been developed along the western and northern margins of the Sichuan basin since Triassic, receiving sediments with significant along-strike variations. These sediment records provide useful insights into the history of mountain building around the Sichuan Basin. We have collected exploration well data from western Sichuan Basin. Using backstripping, we reconstructed the basement deformation history, which reflect sedimentary and tectonic loadings related to mountain building. We used a 3-D numerical modeling technique with multi-grid technique to simulate flexural deformation of the Sichuan Basin lithosphere, and to infer tectonic loading and mountain building along western and northern margins of the Sichuan Basin from the late Triassic to the Cenozoic. Our results suggest that the shortening of the Daba Shan and Michuan Shan orogens mainly occurred during the late Jurassic-Cretaceous. During Cenozoic, the tectonic loading mainly occurred along the southwestern margins of the Sichuan Basin, corresponding to the development of the Longmen Shan mountain belt. The tectonic loading of the northern Longmen Shan on the Sichuan Basin has been markedly reduced since the Cenozoic, evidenced by the lack of Cenozoic foreland basin development. This indicates mechanical decoupling between uplift of the Tibetan Plateau and the Sichuan Basin, consistent with the deep down-cutting of the Longmen Shan fault and predominantly strike-slip motion on the fault. The limited Cenozoic foreland basin development in the southwestern margin of the Sichuan Basin is consistent with localized high-angle thrusting of the southern Longmen Shan mountains. This work was supported by the National Natural Science Foundation of China (grants 41104046).

  9. Extinction of Harrington's Mountain Goat

    NASA Astrophysics Data System (ADS)

    Mead, Jim I.; Martin, Paul S.; Euler, Robert C.; Long, Austin; Jull, A. J. T.; Toolin, Laurence J.; Donahue, Douglas J.; Linick, T. W.

    1986-02-01

    Keratinous horn sheaths of the extinct Harrington's mountain goat, Oreamnos harringtoni, were recovered at or near the surface of dry caves of the Grand Canyon, Arizona. Twenty-three separate specimens from two caves were dated nondestructively by the tandem accelerator mass spectrometer (TAMS). Both the TAMS and the conventional dates indicate that Harrington's mountain goat occupied the Grand Canyon for at least 19,000 years prior to becoming extinct by 11,160 ± 125 radiocarbon years before present. The youngest average radiocarbon dates on Shasta ground sloths, Nothrotheriops shastensis, from the region are not significantly younger than those on extinct mountain goats. Rather than sequential extinction with Harrington's mountain goat disappearing from the Grand Canyon before the ground sloths, as one might predict in view of evidence of climatic warming at the time, the losses were concurrent. Both extinctions coincide with the regional arrival of Clovis hunters.

  10. Extinction of Harrington's mountain goat

    SciTech Connect

    Mead, J.I.; Martin, P.S.; Euler, R.C.; Long, A.; Jull, A.J.T.; Toolin, L.J.; Donahue, D.J.; Linick, T.W.

    1986-02-01

    Keratinous horn sheaths of the extinct Harrington's mountain goat, Oreamnos harringtoni, were recovered at or near the surface of dry caves of the Grand Canyon, Arizona. Twenty-three separate specimens from two caves were dated nondestructively by the tandem accelerator mass spectrometer (TAMS). Both the TAMS and the conventional dates indicate that Harrington's mountain goat occupied the Grand Canyon for at least 19,000 years prior to becoming extinct by 11,160 +/- 125 radiocarbon years before present. The youngest average radiocarbon dates on Shasta ground sloths, Nothrotheriops shastensis, from the region are not significantly younger than those on extinct mountain goats. Rather than sequential extinction with Harrington's mountain goat disappearing from the Grand Canyon before the ground sloths, as one might predict in view of evidence of climatic warming at the time, the losses were concurrent. Both extinctions coincide with the regional arrival of Clovis hunters.

  11. Mid-pacific mountains revisited

    NASA Astrophysics Data System (ADS)

    Kroenke, Loren W.; Kellogg, James N.; Nemoto, Kenji

    1985-06-01

    The Mid-Pacific Mountains are guyots whose volcanic pedestals have been constructed on a broad basement plateau, the flanks of which are downfaulted. Edifice construction may have been controlled by an orthogonal system of intersecting faults trending roughly ENE and NNW. Low amplitude gravity anomalies observed over the Mid-Pacific Mountains indicate complete Airy-Heiskanen isostatic compensation, crustal thickening, and eruption on thin elastic lithosphere. Tholeiites of the Mid-Pacific Mountains resemble lavas of Iceland and the Galapagos Islands. The orthogonal fault system, low gravity anomalies, and lava chemistry of the Mid-Pacific Mountains can be explained by eruption on or near a great ENE-trending rift system.

  12. The Dilemma of Mountain Roads

    EPA Science Inventory

    Mountain roads and trails are proliferating throughout developing Southeast Asia with severe but largely unrecognized long-term consequences related to effects of landslides and surface erosion on communities and downstream resources.

  13. Geography and Weather: Mountain Meterology.

    ERIC Educational Resources Information Center

    Mogil, H. Michael; Collins, H. Thomas

    1990-01-01

    Provided are 26 ideas to help children explore the effects of mountains on the weather. Weather conditions in Nepal and Colorado are considered separately. Nine additional sources of information are listed. (CW)

  14. The Generation of Downwind Rainbands by Mountains

    NASA Astrophysics Data System (ADS)

    Wright, Carly; Gray, Sue; Kirshbaum, Daniel; Schultz, David

    2016-04-01

    In this study we investigate rainbands that form downwind of mountainous terrain using both observational data and output from an operational forecast model. Although relatively small in scale (a few tens of km across by up to ˜100 km in length), these often poorly forecast bands can cause localised flooding as they can be associated with intense precipitation over several hours due to the anchoring effect of orography. A case study is performed of a rainband that was observed over Scotland on the 29 December 2012. This case study was chosen due to the occurrence of heavy continuous precipitation near orography. Radar images during the event showed a clear band along The Great Glen Fault, a deep valley between the Northern Highlands and the Grampian Mountains. The deterministic convection-permitting high-resolution Met Office model forecast, using the United Kingdom Variable resolution (UKV) model (1.5 km horizontal grid spacing), failed to represent this band. However, some members of the ensemble convection-permitting (MOGREPS-UK) Met Office forecast produced a similar band to that observed. Localised convergence and weak convective available potential energy (CAPE) along the fault supported the formation of the valley band. To determine the effect of model resolution on the model's representation of the rainband, a forecast was performed with the horizontal grid spacing decreased to 500 m. In this forecast a rainband formed in the correct location which generated precipitation accumulations close to those observed, but with a time displacement. Work is in progress to assess the robustness of this forecast skill improvement by embedding simulations at the same resolution within the operational global (MOGREPS-G) ensemble members. Results to date suggest that accurate representation of mesoscale rainbands requires model resolutions higher than those used operationally by national weather centres.

  15. Oroclinal bending, distributed deformation, and Arabia-Eurasia convergence in NE Iran

    NASA Astrophysics Data System (ADS)

    Mac Niocaill, C.; Alimohammadian, H.; Walker, R. T.; Hollingsworth, J.

    2013-05-01

    The collision of Arabia with Eurasia has produced significant region shortening across wide areas of Iran. These plates converge in a N-S direction at about 25mm/yr, and virtually the entire active collision zone is contained with the geographical and political boundaries of the country. Many features of continental tectonics are well preserved within the region, such as the partitioning of oblique motions onto parallel strike-slip and thrust faults, the concentration of deformation around the boundaries of rigid blocks, and the rotations of tectonic blocks around vertical axes. The collision zone terminates abruptly in the NE of the country, with active deformation trending N-S along the border with Afghanistan, and this is converted into shortening in the Kopeh Dagh and Alborz mountains. There mountain ranges changing from a NW-SE trend along the border with Turkmenistan to an E-W trend in Northern Iran. In the eastern Alborz mountains, the overall pattern of N-S shortening is accommodated on major thrust systems bounding the eastern branch of the Alborz (east of 57°E), Sabzevar, andKuh-e-Sorkh mountain ranges, which lie south of the Kopeh Dagh mountains. This shortening has resulted in significant crustal thickening, forming peaks up to 3000m high. To the west of 57°E much of the convergence seems to be accommodated on large left-lateral strike-slip faults. Active shortening dies out eastward into Afghanistan, which is thought to belong to stable Eurasia. This change in deformation style has given rise to a significant curvature of the eastern Alborz, and a major issue of contention is whether this curvature reflects a component of oroclinal bending of an originally linear mountain belt that has been rotated to its present configuration of whether the motion is purely translational. We present new palaeomagnetic data from Neogene sediments, distributed across NE Iran that provide new constraints on the deformation of the region. A complex pattern of both

  16. Atlas Mountain Range, Mali, Africa

    NASA Technical Reports Server (NTRS)

    1992-01-01

    ATLAS pallets are backdropped against the Atlas Mountains (31.0N, 1.0W). ATLAS is an acronym for ATmospheric Laboratory for Applications and Science. Taken from a point over Mali, in the western Sahara, the northwest looking view shows dunes in the Iguidi dune sea and colors characteristic of the Saharan side of the Atlas Mountains. The edge of a large sandstorm, that transported sand and dust to Yugoslavia and beyond, can also be seen.

  17. Io: Mountains and crustal extension

    NASA Technical Reports Server (NTRS)

    Heath, M. J.

    1985-01-01

    It is argued that there is good reason to conclude that mountains on Io, like those on Earth, are subject to growth and decay. The decay of mountains will be assisted by the ability of SO sub 2 to rot silicate rock and by explosive escape of sub-surface SO sub 2 from aquifers (Haemus Mons is seen to be covered by bright material, presumably fallout from a SO sub 2 rich plume which had been active on the mountain flanks). On the west side of the massif at 10 degrees S, 270 degrees W a rugged surface consists of long ridges running perpendicular to the downslope direction, suggesting tectonic denudation with crustal blocks sliding down the mountain flank. Tectonic denudation may be assisted, as in the case of the Bearpaw Mountains, Montana by overloading mountain flanks with volcanic products. The surfaces of some massifs exhibit a well developed, enigmatic corrugated terrain, consisting of complex ridge systems. Ridges may bifurcate, anastomose to form closed depressions and form concentric loops. Taken together, observations of morphology, heat flux, surface deposits and styles of volcanism may point to the existence of lithosphere domains with distinct compositions and tectonic regimes.

  18. Uplift of the Transantarctic Mountains

    SciTech Connect

    Stump, E.

    1987-09-01

    The Transantarctic Mountains, a major continental range, extend approximately 3,000 kilometers, vary from less than 50 to more than 400 kilometers wide, and have elevations of up to 4,500 meters. Earth scientists have generally defined the stratigraphy of the range and recognize that uplift of the region occurred after the Jurassic period but still know very little about the processes that effected uplift. Unlike other major mountain chains, the Transantarctic Mountains show no evidence of thrusting, folding, regional metamorphism, and andesitic volcanism associated with their uplift. The objectives during austral summer 1987-1988 are to map the uplift geometry of the Transantarctic Mountains using erosion surfaces (pre-Devonian Kukir peneplain) and widespread terrace levels as datum planes and to determine the uplift rates for the mountain range using fission-track dating of apatites. Presently, fission-track dating provides only quantitative data on the initiation time, amount, and rate of uplift. Through research, the authors hopes to extend data from Victoria Land through 1,600 kilometers of the Transantarctic Mountains. This study also has implications for the glacial history of Antarctica, because the uplift occurred during the inception, growth, and subsequent fluctuations of the east and west antarctic ice sheets. It will also add to our understanding of the nature of the East-West Antarctic boundary and to the knowledge of the sedimentation history in the Ross embayment and the basins beneath polar plateau.

  19. SULFUR DYNAMICS IN MINERAL HORIZONS OF TWO NORTHERN HARDWOOD SOILS A COLUMN STUDY WITH 35S

    EPA Science Inventory

    Sulfur dynamics of two Spodosols were ascertained using soil columns constructed from homogenized mineral soil from northern hardwood ecosystems at the Huntington Forest (HF) in the Adirondack Mountains of New York and Bear Brook Watershed in Maine (BBWM). olumns were leached for...

  20. The Hispano Ranchos of Northern New Mexico: Continuity and Change. Teaching with Historic Places.

    ERIC Educational Resources Information Center

    Koman, Rita G.

    Northern New Mexico boasts river valleys surrounded by snow covered mountains. But it is also harsh and unforgiving. One settler called it a "glorious hell." The "Hispanos," as the early Spanish settlers and their descendants were called, and the "Anglos," the immigrants from the east, were often in conflict. The physical fabric of their early…

  1. Debris-Flow Hazards within the Appalachian Mountains of the Eastern United States

    USGS Publications Warehouse

    Wieczorek, Gerald F.; Morgan, Benjamin A.

    2008-01-01

    Tropical storms, including hurricanes, often inflict major damage to property and disrupt the lives of people living in coastal areas of the Eastern United States. These storms also are capable of generating catastrophic landslides within the steep slopes of the Appalachian Mountains. Heavy rainfall from hurricanes, cloudbursts, and thunderstorms can generate rapidly moving debris flows that are among the most dangerous and damaging type of landslides. This fact sheet explores the nature and occurrence of debris flows in the central and southern Appalachian Mountains, which extend from central Pennsylvania to northern Alabama.

  2. Mineral resources of the Bull Mountain Wilderness Study Area, Garfield and Wayne counties, Utah

    SciTech Connect

    Dubiel, R.F.; Bromfield, C.S.; Church, S.E.; Kemp, W.M.; Larson, M.J.; Peterson, F.

    1988-01-01

    The US Geological Survey and the US Bureau of Mines conducted studies to appraise the mineral resources and mineral resource potential of the Bull Mountain Wilderness Study Area. The study area contains sedimentary rocks ranging in age from Jurassic and Triassic( ) to Cretaceous that have been intruded by Tertiary igneous stocks, lacoliths, and bysmaliths. No mines or prospects or identified resources are present within the study area. The northern half of the Bull Mountain Wilderness Study Area has a high mineral resource potential for gypsum, and the entire study area has a low resource potential for uranium and vanadium, coal, oil and gas, and geothermal energy.

  3. Observing Globular Cluster RR Lyraes with the BYU West Mountain Observator

    NASA Astrophysics Data System (ADS)

    Jeffery, Elizabeth; Joner, Michael D.

    2016-01-01

    We have utilized the 0.9-meter telescope of the Brigham Young University West Mountain Observatory to secure data on six northern hemisphere globular clusters. Here we present observations of RR Lyrae stars located in these clusters, including light curves. We compare light curves produced using both DAOPHOT and ISIS software packages. Light curve fitting is done with FITLC. We acknowledge continued support from the Brigham Young University College of Physical and Mathematical sciences for operation of the West Mountain Observatory. Some of the observations included in this presentation were secured within the term of NSF grant AST-0618209.

  4. Detailed interpretation of aeromagnetic data from the Patagonia Mountains area, southeastern Arizona

    USGS Publications Warehouse

    Bultman, Mark W.

    2015-01-01

    Euler deconvolution depth estimates derived from aeromagnetic data with a structural index of 0 show that mapped faults on the northern margin of the Patagonia Mountains generally agree with the depth estimates in the new geologic model. The deconvolution depth estimates also show that the concealed Patagonia Fault southwest of the Patagonia Mountains is more complex than recent geologic mapping represents. Additionally, Euler deconvolution depth estimates with a structural index of 2 locate many potential intrusive bodies that might be associated with known and unknown mineralization.

  5. Rocky Mountain spotted fever.

    PubMed

    Comer, K M

    1991-01-01

    Rocky Mountain spotted fever is an endemic tickborne disease found throughout the United States and other regions of the world. Exposure may result in a spectrum of disease from subclinical infection to severe or fatal multiorgan collapse. The disease is maintained in nature in Ixodid tick vectors and their hosts. The most important ticks in the United States are Dermacentor variabilis and Dermacentor andersoni. Small mammals are the natural reservoirs in the wild. Dogs become infected when a tick harboring Rickettsia rickettsii feeds on the dog. Dogs do not develop sufficient rickettsemia to act as a reservoir in the transmission of Rickettsia rickettsii. Thus, although dogs act as sentinels to the presence of the disease, they cannot directly transmit infection. Signs in early stages of disease often are nonspecific. The most characteristic laboratory abnormality is thrombocytopenia, but serologic testing is necessary for confirmation of infection. Tetracycline and chloramphenicol are effective antibiotics to treat infection. Treatment should continue for 14 to 21 days to allow host immune defenses to develop and eradicate the organism. Prevention requires avoidance of tick-infested areas and rapid removal of ticks should exposure occur. PMID:2014623

  6. Thermochronology applied to the Chiapas mountains, Mexico.

    NASA Astrophysics Data System (ADS)

    Brichau, S.; Witt, C.; Carter, A.

    2008-12-01

    The Chiapas area is located at a triple junction between the Caribbean, North American and Cocos plates. It is an ideal area to investigate how tectonics influence landscape development and surface processes in the context of erosion, sediment routing and sedimentary basin evolution. At present the long-term evolution of the Chiapas Mountain is not well understood especially regarding the timing and magnitude of tectonic phases that led to formation of the Chiapas Mountains and its present-day topography. This area is mainly formed by the Permian Chiapas batholith (~250 Ma) and the Chiapas sierra. Important stratigraphic changes in nature and thickness lead authors to consider that up to six tectonic 'phases' participated in mountain formation and evolution. In this way, each major change in sediment nature, from marine to continental, has been related to uplift of the batholith and increase of sediment input. The onset of deformation along the region results from the northward migration of the left-lateral strike slip systems which is connected, further south, to the Polochic-Motagua fault system (i.e. limit between the North America and Caribbean plates). In this tectonic setting deformation along the Chiapas area results from the transpressive component of deformation related to the relative motion of the North American and Caribbean plates. A regional thermochronological study has been initiated to constrain the location, timing and magnitude of rock uplift associated with this transpressive regime. Thermochronometry will also help to constrain links to sedimentary basin development by identifying possible source areas (based on the assumption that exhumation of uplifted blocks is accompanied by erosion) and constrain sediment routing. U-Pb results obtained on the Palaeocene-Miocene series of the Sierra shows an important component from Greenvillian- type basement rocks (i.e. 0.8-1Ga) that have not been identified along the Chiapas region. The most likely

  7. Mountain geomorphosites in Odle Group (Dolomites, Italy)

    NASA Astrophysics Data System (ADS)

    Coratza, Paola; Ghinoi, Alessandro; Marchetti, Mauro; Soldati, Mauro

    2016-04-01

    The area, considered in the present study, is located in the north-eastern sector of the Gardena valley, in the Odle Group, a popular destination of summer and winter tourism (more than 3000 m a.s.l.). The area has a strong hiking-tourism vocation thanks to its spectacular high-mountain landscape and a dense network of hiking tracks. The well-developed network of hiking paths and slopes for many different climbing skills offers a lot of possibilities for high-mountain excursions. Permanent dwelling-places are absent with the exceptions of a few tourist structures nearby opened during certain periods of the year. This area, as all Dolomites, which became UNESCO Word Heritage Site in 2009, represent landscape mosaics, which express the summation of landscape histories and processes offering an almost complete educational open-air laboratory due to the variety and complexity of phenomena and processes taking place during present climate conditions and during recent geological periods. These mountains, due to the aggregation of relict, recent and active landforms constitute an outstanding geoheritage, suitable for educational and tourist purposes. Landforms typical of past morphoclimatic conditions (inherited geomorphosites) share the stage with forms and processes active in the current morphoclimatic conditions (active geomorphosites); their spatial and geometrical relationships may be sufficient to trace a relative time-line of the geomorphological history of the area. Several glacial landforms testify for the presence and the activity of a glacial tongue hosted in the valley during the Lateglacial, mainly located in the northern sector of the area, where altitudes range from about 2000 m to about 2300 m a.s.l. Among these, worth of note are the well-preserved glacial cirques of Val dla Roa and those located at the southern margin of the Odle Group. Quite well preserved moraine ridges are present at a mean altitude of some 2000 m at the Alpe di Cisles as well as

  8. Two new water beetles from the Hantamsberg, an inselberg in the Northern Cape of South Africa (Coleoptera, Hydraenidae).

    PubMed

    Bilton, David T

    2014-01-01

    Mesoceration hantam sp. nov. and Parhydraena faeni sp. nov., are described from the Hantamsberg plateau, an inselberg in the Northern Cape of South Africa. The new species are so far known only from temporary waters on the Hantamsberg summit, where they were both abundant. Sampling in these mountains also revealed an interesting accompanying water beetle fauna, including the northernmost known record of Hydropeplus montanus Omer-Cooper, a species characteristic of mountain fynbos further south in the region. PMID:25543944

  9. Current and Potential Tree Locations in Tree Line Ecotone of Changbai Mountains, Northeast China: The Controlling Effects of Topography

    PubMed Central

    Zong, Shengwei; Wu, Zhengfang; Xu, Jiawei; Li, Ming; Gao, Xiaofeng; He, Hongshi; Du, Haibo; Wang, Lei

    2014-01-01

    Tree line ecotone in the Changbai Mountains has undergone large changes in the past decades. Tree locations show variations on the four sides of the mountains, especially on the northern and western sides, which has not been fully explained. Previous studies attributed such variations to the variations in temperature. However, in this study, we hypothesized that topographic controls were responsible for causing the variations in the tree locations in tree line ecotone of the Changbai Mountains. To test the hypothesis, we used IKONOS images and WorldView-1 image to identify the tree locations and developed a logistic regression model using topographical variables to identify the dominant controls of the tree locations. The results showed that aspect, wetness, and slope were dominant controls for tree locations on western side of the mountains, whereas altitude, SPI, and aspect were the dominant factors on northern side. The upmost altitude a tree can currently reach was 2140 m asl on the northern side and 2060 m asl on western side. The model predicted results showed that habitats above the current tree line on the both sides were available for trees. Tree recruitments under the current tree line may take advantage of the available habitats at higher elevations based on the current tree location. Our research confirmed the controlling effects of topography on the tree locations in the tree line ecotone of Changbai Mountains and suggested that it was essential to assess the tree response to topography in the research of tree line ecotone. PMID:25170918

  10. Worldwide acceleration of mountain erosion under a cooling climate.

    PubMed

    Herman, Frédéric; Seward, Diane; Valla, Pierre G; Carter, Andrew; Kohn, Barry; Willett, Sean D; Ehlers, Todd A

    2013-12-19

    Climate influences the erosion processes acting at the Earth's surface. However, the effect of cooling during the Late Cenozoic era, including the onset of Pliocene-Pleistocene Northern Hemisphere glaciation (about two to three million years ago), on global erosion rates remains unclear. The uncertainty arises mainly from a lack of consensus on the use of the sedimentary record as a proxy for erosion and the difficulty of isolating the respective contributions of tectonics and climate to erosion. Here we compile 18,000 bedrock thermochronometric ages from around the world and use a formal inversion procedure to estimate temporal and spatial variations in erosion rates. This allows for the quantification of erosion for the source areas that ultimately produce the sediment record on a timescale of millions of years. We find that mountain erosion rates have increased since about six million years ago and most rapidly since two million years ago. The increase of erosion rates is observed at all latitudes, but is most pronounced in glaciated mountain ranges, indicating that glacial processes played an important part. Because mountains represent a considerable fraction of the global production of sediments, our results imply an increase in sediment flux at a global scale that coincides closely with enhanced cooling during the Pliocene and Pleistocene epochs. PMID:24352288

  11. Bioactive compounds from northern plants.

    PubMed

    Hohtola, Anja

    2010-01-01

    Northern conditions are characterised by long days with much light and low temperatures during the growing season. It has been chimed that herbs and berries grown in the north are stronger tasting compared to those of southern origin. The compounds imparting aroma and color to berries and herbs are secondary metabolites which in plants mostly act as chemical means of defense. Recently, the production of secondary metabolites using plant cells has been the subject of expanding research. Light intensity, photoperiod and temperature have been reported to influence the biosynthesis of many secondary metabolites. Native wild aromatic and medicinal plant species of different families are being studied to meet the needs of raw material for the expanding industry of e.g., health-promoting food products known as nutraceutics. There are already a large number of known secondary compounds produced by plants, but the recent advances in modern extraction and analysis should enable many more as yet unknown compounds to be found, characterised and utilised. Rose root (Rhodiola rosea) is a perennial herbaceous plant which inhabits mountain regions throughout Europe, Asia and east coastal regions of North America. The extract made from the rhizomes acts as a stimulant like the Ginseng root. Roseroot has been categorized as an adaptogen and is reported to have many pharmacological properties. The biologically active components of the extract are salitroside tyrosol and cinnamic acid glycosides (rosavin, rosarin, rosin). Round-leaved sundew (Drosera rotundifolia L.) has circumboreal distribution. It inhabits nutrient-poor, moist and sunny areas such as peat bogs and wetlands. Sundew leaves are collected from the wild-type for various medicinal preparations and can be utilized in treating e.g., as an important "cough-medicine" for different respiratory diseases. The antimicrobial activity of extracts of aerial parts against various bacteria has been investigated. Drosera produces

  12. Hydrometeorology of Rocky Mountain floods

    NASA Astrophysics Data System (ADS)

    Jarrett, Robert D.

    Climatology and flood hydrology of the Rocky Mountains were the topics of a workshop held in Lakewood, Colo., October 4-5, 1990. Ninety-one people participated in the workshop, which was organized by Robert Jarrett, U.S. Geological Survey, Denver; John Liou, Federal Emergency Management Agency, Denver; and Doug Laiho, Delta Environmental Consultants, Boulder, representing the American Society of Civil Engineers.The workshop was held to address some of the recognized complexities in the hydrometeorology of floods in the Rocky Mountains. The complexities are caused by the effects of rough mountain terrain on meteorology, snowmelt and rainfall flooding, and limited rainfall and streamflow data. The current theories and methods used to estimate flood flows in the Rocky Mountains, particularly estimation of the probable maximum precipitation (PMP) and the probable maximum flood (PMF), have been questioned by hydrologists and engineers for some time. Purposes of the workshop were to review the current understanding and ongoing research of floods—both frequent and extreme, including the PMF, in the Rocky Mountains; to bring together scientists, engineers, and flood-plain managers in government, industry, consulting firms, and universities; and to provide a mechanism for the exchange of ideas and technology between climatologists, meteorologists, hydrologists, engineers, and managers.

  13. Mountain biking injuries: an update.

    PubMed

    Kronisch, Robert L; Pfeiffer, Ronald P

    2002-01-01

    This article reviews the available literature regarding injuries in off-road bicyclists. Recent progress in injury research has allowed the description of several patterns of injury in this sport. Mountain biking remains popular, particularly among young males, although sales and participation figures have decreased in the last several years. Competition in downhill racing has increased, while cross-country racing has decreased somewhat in popularity. Recreational riders comprise the largest segment of participants, but little is known about the demographics and injury epidemiology of noncompetitive mountain cyclists. Most mountain bikers participating in surveys reported a history of previous injuries, but prospective studies conducted at mountain bike races have found injury rates of <1%. The most common mechanism of injury involves a forward fall over the handlebars, usually while riding downhill, which can result in direct trauma to the head, torso and upper extremities. A variety of factors can be associated with this type of fall, including trail surface irregularities, mechanical failures and loss of control. In mountain bike racing the risk of injury may be higher for women than men. Minor injuries such as abrasions and contusions occur frequently, but are usually of little consequence. Fractures usually involve the torso or upper extremities, and shoulder injuries are common. Head and face injuries are not always prevented by current helmet designs. Fatal injuries are rare but have been reported. Improvements in safety equipment, rider training and racecourse design are suggested injury prevention measures. The authors encourage continued research in this sport. PMID:12076178

  14. Aerosol pollution over Northern India and Bangladesh

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The skies over Northern India are filled with a thick soup of aerosol particles all along the southern edge of the Himalayan Mountains, and streaming southward over Bangladesh and the Bay of Bengal. Notice that the air over the Tibetan Plateau to the north of the Himalayas is very clear, whereas the view of the land surface south of the mountains is obstructed by the brownish haze. Most of this air pollution comes from human activities. The aerosol over this region is notoriously rich in sulfates, nitrates, organic and black carbon, and fly ash. These particles not only represent a health hazard to those people living in the region, but scientists have also recently found that they can have a significant impact on the region's hydrological cycle and climate (click to read the relevant NASA press release). This true-color image was acquired on December 4, 2001, by the Moderate-resolution Imaging Spectroradiometer (MODIS), flying aboard NASA's Terra satellite. It is interesting to compare the image above with this earlier MODIS image over the region, acquired on October 23, 2001. Notice the difference in the clarity of the air over the region in the earlier image. Under the thick plume of aerosol, the Brahmaputra (upper right) and Ganges Rivers are still visible. The many mouths of the Ganges have turned the northern waters of the Bay of Bengal a murky brown as they empty their sediment-laden waters into the bay. Toward the upper lefthand corner of the image, there appears to be a fresh swath of snow on the ground just south of the Himalayas.

  15. Mountaineer`s gas facilities decision support system

    SciTech Connect

    1997-02-01

    Mountaineer Gas Co. of Charleston, W.Va., is justifiably proud of its capacity to combine electronic maps with a full database of information about its facilities and customers, and use that mix to make the decisions required in operating a gas company with better information and more quickly. Determining when a pipeline needs replacement or repair used to take several days at Mountaineer. With the new system in place, the decision can be made in a matter of minutes. The paper describes the system and its development, then discusses adding customer information as the next step.

  16. STS-45 Earth observation of the Rocky Mountains in Montana and Alberta

    NASA Technical Reports Server (NTRS)

    1992-01-01

    STS-45 Earth observation taken onboard Atlantis, Orbiter Vehicle (OV) 104, is of the Rocky Mountains in northern Montana and southern Alberta. Glacier National Park is in the center of the snow-covered Front Range. Beyond and to the left, Flathead Lake, surrounded by dark forest, can barely be made out within the light-colored valley. This view extends across the Columbia River Basin in Oregon to the eastern Cascades. Fallow wheat land on the northern High Plains is visible in the foreground.

  17. Passive Seismic Imaging of the Ruby Mountains Core Complex, Nevada

    NASA Astrophysics Data System (ADS)

    Litherland, M.; Klemperer, S. L.

    2015-12-01

    We investigate the deep crustal structure of the Ruby Mountains Core Complex (RMCC) using data collected from the Ruby Mountains Seismic Experiment. This project, part of the Earthscope Flexible Array program, deployed 50 passive broadband stations across the RMCC from 2010 to 2012. Previous investigations of the area have included extensive surface mapping and active seismic profiles across the surrounding basins, but better imaging beneath the mountain range is needed to understand the tectonic processes that formed the RMCC. The RMCC exhibits typical core-complex structure of deep crustal rocks exhumed to the surface beneath a gently dipping detachment, with a thick mylonitic shear zone directly underlying the detachment. In the RMCC, the westward dip of the detachment, the ~1km-thick mylonite zone formed in the Paleogene, and a south-to-north increase in metamorphic grade provide targets for imaging. We used common conversion point stacking of receiver functions to produce 3 profiles of structural discontinuities beneath the RMCC: one along the axis of the RMCC, and two crossing lines, one in the northern RMCC, and one in the southern part of the range. Due to the deep sedimentary basins surrounding the RMCC, various de-multiple processes were required to reduce the effects of basin reverberations. To better constrain the velocity structure of the area, we used ambient-noise tomography, and finally, we produced a joint inversion of our receiver functions and ambient-noise data. We observe a mostly flat Moho at about 30 km depth beneath the RMCC that dips slightly to the south, with faint mid-crustal converters that also dip south at ~30°. In the southern RMCC, the Moho dips ~20° westward, but this is not observed in the northern RMCC. This suggests that much of the exhumation involved in the RMCC formation likely involved ductile flow that left a mostly flat Moho, but more recent processes also may have left observable changes in lower-crustal structure.

  18. Regional metamorphism in the Condrey Mountain Quadrangle, north-central Klamath Mountains, California

    USGS Publications Warehouse

    Hotz, Preston Enslow

    1979-01-01

    A subcircular area of about 650 km 2 in northern California and southwestern Oregon is occupied by rocks of the greenschist metamorphic facies called the Condrey Mountain Schist. This greenschist terrane is bordered on the east and west by rocks belonging to the amphibolite metamorphic facies that structurally overlie and are thrust over the Condrey Mountain Schist. The amphibolite facies is succeeded upward by metavolcanic and metasedimentary rocks belonging to the greenschist metamorphic facies. The Condrey Mountain Schist is composed predominantly of quartz-muscovite schist and lesser amounts of actinolite-chlorite schist formed by the metamorphism of graywacke and spilitic volcanic rocks that may have belonged to the Galice Formation of Late Jurassic age. Potassium-argon age determinations of 141?4 m.y. and 155?5 m.y. obtained on these metamorphic rocks seem to be incompatible with the Late Jurassic age usually assigned the Galice. The rocks that border the amphibolite facies are part of an extensive terrane of metavolcanic and metasedimentary rocks belonging to the western Paleozoic and Triassic belt. The metavolcanic rocks include some unmetamorphosed spilite but are mostly of the greenschist metamorphic facies composed of oligoclase (An15-20) and actinolite with subordinate amounts of chlorite and clinozoisiteepidote. The interbedded sedimentary rocks are predominantly argillite and slaty argillite, less commonly siliceous argillite and chert, and a few lenticular beds of marble. On the south, high-angle faults and a tabular granitic pluton separate the greenschist metavolcanic terrane from the amphibolite facies rocks; on the east, nonfoliated amphibolite is succeeded upward, apparently conformably, by metasedimentary rocks belonging to the greenschist metavolcanic terrane. In the southern part of Condrey Mountain quadrangle, an outlier of a thrust plate composed of the Stuart Fork Formation overlies the metavolcanic and metasedimentary rocks. The Stuart

  19. 10. SLIGHTLY OBLIQUE VIEW OF EAGLE MOUNTAIN PUMP COMPLEX. NOTE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. SLIGHTLY OBLIQUE VIEW OF EAGLE MOUNTAIN PUMP COMPLEX. NOTE AUXILIARY STRUCTURES. - Eagle Mountain Pump Plant, Ten miles north of Route 10, southeast of Eagle Mountain, Eagle Mountain, Riverside County, CA

  20. Timber Mountain Precipitation Monitoring Station

    SciTech Connect

    Lyles, Brad; McCurdy, Greg; Chapman, Jenny; Miller, Julianne

    2012-01-01

    A precipitation monitoring station was placed on the west flank of Timber Mountain during the year 2010. It is located in an isolated highland area near the western border of the Nevada National Security Site (NNSS), south of Pahute Mesa. The cost of the equipment, permitting, and installation was provided by the Environmental Monitoring Systems Initiative (EMSI) project. Data collection, analysis, and maintenance of the station during fiscal year 2011 was funded by the U.S. Department of Energy, National Nuclear Security Administration, Nevada Site Office Environmental Restoration, Soils Activity. The station is located near the western headwaters of Forty Mile Wash on the Nevada Test and Training Range (NTTR). Overland flows from precipitation events that occur in the Timber Mountain high elevation area cross several of the contaminated Soils project CAU (Corrective Action Unit) sites located in the Forty Mile Wash watershed. Rain-on-snow events in the early winter and spring around Timber Mountain have contributed to several significant flow events in Forty Mile Wash. The data from the new precipitation gauge at Timber Mountain will provide important information for determining runoff response to precipitation events in this area of the NNSS. Timber Mountain is also a groundwater recharge area, and estimation of recharge from precipitation was important for the EMSI project in determining groundwater flowpaths and designing effective groundwater monitoring for Yucca Mountain. Recharge estimation additionally provides benefit to the Underground Test Area Sub-project analysis of groundwater flow direction and velocity from nuclear test areas on Pahute Mesa. Additionally, this site provides data that has been used during wild fire events and provided a singular monitoring location of the extreme precipitation events during December 2010 (see data section for more details). This letter report provides a summary of the site location, equipment, and data collected in

  1. Rocky Mountain Snowpack Chemistry at Selected Sites, 2004

    USGS Publications Warehouse

    Ingersoll, George P.; Mast, M. Alisa; Nanus, Leora; Handran, Heather H.; Manthorne, David J.; Hultstrand, Douglas M.

    2007-01-01

    During spring 2004, the U.S. Geological Survey in cooperation with the National Park Service and the U.S. Department of Agriculture, Forest Service collected and analyzed snowpack samples for 65 sites in the Rocky Mountain region from New Mexico to Montana. Snowpacks were sampled from late February through early April and generally had well-below-average- to near-average snow-water equivalent. Regionally, on April 1, snow-water equivalent ranged from 50 to 89 percent. At most regional sites monitored during 1993-2004, snowpack ammonium, nitrate, and sulfate concentrations for 2004 were lower than the 12-year averages. Snowpack ammonium concentrations in the region were lower than average concentrations for the period at 61 percent of sites in the region, but showed a new pattern compared to previous years with three of the four highest 2004 concentrations observed in northern Colorado. Nitrate concentrations in 2004 were lower than the 12-year average for the year at 53 percent of regional sites, and typically occurred at sites in Wyoming, Idaho, and Montana where powerplants and large industrial areas were limited. A regional decrease in sulfate concentrations across most of the Rocky Mountains (with concentrations lower than the 12-year average at 84 percent of snowpack sites) was consistent with other monitoring of atmospheric deposition in the Western United States. Total mercury concentrations, although data are only available for the past 3 years, decreased slightly for the region as a whole in 2004 relative to 2003. Ratios of stable sulfur isotopes indicated a similar regional pattern as observed in recent years with sulfur-34 (d34S) values generally increasing northward from northern New Mexico and southern Colorado to northern Colorado, Wyoming, Idaho, and Montana.

  2. BLOOD MOUNTAIN ROADLESS AREA, GEORGIA.

    USGS Publications Warehouse

    Koeppen, Robert P.; Armstrong, Michelle K.

    1984-01-01

    A mineral-resource survey of the Blood Mountain Roadless Area, Georgia, indicates that there is little promise for the occurrence of mineral and energy resources. Natural gas may be present at great depth, perhaps 5 mi down and below the overthrust sheets of the Blue Ridge Mountains, but presently available information is not adequate to evaluate the resource potential of this commodity. Further seismic studies and exploratory drilling are needed to evaluate the gas potential of this part of the Eastern Overthrust Belt.

  3. Yearly report, Yucca Mountain project

    SciTech Connect

    Brune, J.N.

    1992-09-30

    We proposed to (1) Develop our data logging and analysis equipment and techniques for analyzing seismic data from the Southern Great Basin Seismic Network (SGBSN), (2) Investigate the SGBSN data for evidence of seismicity patterns, depth distribution patterns, and correlations with geologic features (3) Repair and maintain our three broad band downhole digital seismograph stations at Nelson, nevada, Troy Canyon, Nevada, and Deep Springs, California (4) Install, operate, and log data from a super sensitive microearthquake array at Yucca Mountain (5) Analyze data from micro-earthquakes relative to seismic hazard at Yucca Mountain.

  4. Aeromagnetic search for Cenozoic magmatism over the Admiralty Mountains Block (East Antarctica)

    USGS Publications Warehouse

    Armadillo; E.; Ferraccioli, F.; Zunino, A.; Bozzo, E.; Rocchi, S.; Armienti, P.

    2007-01-01

    Cenozoic magmatic rocks of the Transantarctic Mountains provide an important window on the tectonic and magmatic processes of the West Antarctic Rift System. Previous aeromagnetic investigations in northern Victoria Land have delineated Cenozoic volcanic and intrusive complexes assigned to the McMurdo Volcanic Group and Meander Intrusives over the Transantarctic Mountains. We present a new aeromagnetic anomaly map for the region north of the Mariner Glacier to study the extent and spatial distribution of these Cenozoic rocks over the previously unexplored Admiralty Mountains. The new map shows that the Meander Intrusives are restricted to the coastal region between the Malta Plateau and the Daniell Peninsula. However, the McMurdo Volcanic Group rocks extend further inland, and may delineate a hitherto unrecognised volcano-tectonic rift zone, extending as far north as the Trafalgar Glacier.

  5. A geological reconnaissance across the Bitterroot Range and Clearwater Mountains in Montana and Idaho

    USGS Publications Warehouse

    Lindgren, Waldemar

    1904-01-01

    This report describes, in a preliminary way, a belt of country extending westward from the Bitterroot Valley, across the dividing range and the rugged mountains of the Clearwater system, down to the fertile plateaus which border the canyon of Snake River. It thus presents a reconnaissance section from western Montana across northern Idaho, and deals chiefly with areas about which, thus far, little geological information has been available.

  6. The Biggest Tuya or Table Mountain in the North Atlantic?

    NASA Astrophysics Data System (ADS)

    Helgadottir, G.; Reynisson, P.

    2012-12-01

    Multibeam mapping in cruise A201206 of the Marine Research Institute in June 2012 revealed a huge submarine mountain with a striking look of a tuya. Tuya is by defenition a subrectangular or circular, constructional, flat-topped mountain, made up of hyaloclastites and/or pillow lava, usually with cap lava (Mathews 1947). The mountain lies at 950-1.400 waterdepth some 120 nautical miles west of the Snaefellsnes peninsula and the mapped part of it is around 300 km2. For comparison, the largest tuya in Iceland is Eiriksjokull with a basal area of 77 km2 (Jakobsson and Gudmundsson 2008). Above the mountains edge at 1.100 m waterdepth the hight increases gradually towards the top of the mountain were some craters are exposed. The mountain has a a youthful apperance. Analysing of rock samples are needed to find out if that is the case or if it is connected with an old rifting zone. The goal of the survey was to map fishing areas (f. ex. of the Greenland halibut); to explore the environment of the strong ocean currents coming from north through the Greenland Strait (also called Denmark Strait) but also to gain additional bathymetrical data in the vicinity of what we believe are mud volcanoes, discovered in a fairly recent MRI's mapping cruise. Now, like erlier on, several mud volcanoes appeared, some of them up to 350 m high. If this proves to be right, this is the first finding of these features in Icelandic waters. The research area coincides largely with sediments of the Snorri drift. Seismic lines through this sediment show possible diapir formation (Egloff and Johnson 1978) which strengthens the idea of those features beeing mud volcanoes. The current 9.000 km2 mapping with EM 300 has added significantly to our knowledge of the morphology of the seafloor around Iceland. References: Mathews, W. H. 1947: "Tuyas": Flat-topped volcanoes in northern Brithish Columbia. Amer. J. Sci. 245, 560-570. Jakobsson, S. P. and Gudmundsson, M. T. 2008: Subglacial and intraglacial

  7. Northern Plains 'Crater'

    NASA Technical Reports Server (NTRS)

    2004-01-01

    10 December 2004 The lower left (southwest) corner of this Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the location of a somewhat filled and buried meteor impact crater on the northern plains of Mars. The dark dots are boulders. A portion of a similar feature is seen in the upper right (northeast) corner of the image. This picture, showing landforms (including the odd mound north/northeast of the crater) that are typical of the martian northern lowland plains, was obtained as part of the MGS MOC effort to support the search for a landing site for the Phoenix Mars Scout lander. Phoenix will launch in 2007 and land on the northern plains in 2008. This image is located near 68.0oN, 227.4oW, and covers an area approximately 3 km (1.9 mi) wide. The scene is illuminated by sunlight from the lower left.

  8. Rapid middle Miocene extension and unroofing of the southern Ruby Mountains, Nevada

    USGS Publications Warehouse

    Colgan, Joseph P.; Howard, Keith A.; Fleck, Robert J.; Wooden, Joseph L.

    2010-01-01

    Paleozoic rocks in the northern Ruby Mountains were metamorphosed during Mesozoic crustal shortening and Cenozoic magmatism, but equivalent strata in the southern Ruby Mountains were never buried deeper than stratigraphic depths prior to exhumation in the footwall of a west dipping brittle normal fault. In the southern Ruby Mountains, Miocene sedimentary rocks in the hanging wall of this fault date from 15.2 to 11.6 Ma and contain abundant detritus from the Paleozoic section. Apatite fission track and (U-Th)/He samples of the Eocene Harrison Pass pluton record rapid cooling that peaked ca. 17–15 Ma, while apatite fission track data from Jurassic plutons east and west of the southern Ruby Mountains indicate near-surface temperatures (<60°C) since the Cretaceous. We interpret these data to record rapid unroofing of the southern Ruby Mountains during slip on the west dipping brittle detachment between 17–16 and 10–12 Ma, followed by minor high-angle faulting. We interpret published Oligocene to early Miocene K-Ar biotite and zircon fission track dates from the Harrison Pass pluton to be partially reset rather than to directly record fault slip. Our new data, together with published data on the distribution and composition of Miocene basin fill, suggest that rapid middle Miocene slip took place on the west dipping brittle detachment that bounds the Ruby Mountains and East Humboldt Range for 150 km along strike. This fault was thus active during a period of rapid extension (ca. 17–15 to 12–10 Ma) documented widely across the northern Basin and Range Province.

  9. Provenance of Norphlet sandstone, northern Gulf Coast

    SciTech Connect

    Ryan, W.P.; Ward, W.C.; Kuglar, R.L.

    1987-09-01

    The Upper Jurassic Norphlet sandstone of the northern Gulf Coast is predominantly subarkose, with some arkose in the eastern area and sublitharenite and quartzarenite in the western area. Despite great depths of burial and despite feldspar and rock-fragment constituents, diagenesis has not appreciably altered the composition of Norphlet sandstone. Therefore, reconstruction of original composition of Norphlet sandstone presented little difficulty. Variation in detrital modes of the Norphlet suggests compositionally distinct source terranes. Samples from Florida, Alabama, and Mississippi reflect the influence of metamorphic and plutonic rocks of the Appalachian Piedmont Province and of Triassic-Jurassic volcanic rocks. Sandstones in east Texas, northern Louisiana, and southern Arkansas were derived from sedimentary and metasedimentary rocks of the Ouachita system. The Arbuckle Mountains and Llano uplift may have supplied trace amounts of quartzo-feldspathic and volcanic-rock fragments to the extreme western part of the study area. Norphlet sandstones represent a mixture of collision-orogen-derived sediment from the Appalachian and/or Ouachita system and continental-block-derived sediment from paleohighs and uplifts within the Gulf basin. However, Norphlet sandstones plot in the craton-interior and transitional-continental fields on Q-F-L and QM-F-Lt tectonic-provenance diagrams, because of mineralogically mature source rocks, elimination of unstable grains by abrasion and sorting during deposition, and/or sediment mixing from different source terranes.

  10. 27 CFR 9.94 - Howell Mountain.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Howell Mountain. 9.94... Howell Mountain. (a) Name. The name of the viticultural area described in this section is “Howell Mountain.” (b) Approved maps. The appropriate maps for determining the boundaries of the Howell...

  11. 27 CFR 9.102 - Sonoma Mountain.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Sonoma Mountain. 9.102... Sonoma Mountain. (a) Name. The name of the viticultural area described in this section is “Sonoma Mountain.” (b) Approved maps. The approved maps for determining the boundary of the Sonoma...

  12. 27 CFR 9.112 - Arkansas Mountain.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Arkansas Mountain. 9.112... Arkansas Mountain. (a) Name. The name of the viticultural area described in this section is “Arkansas Mountain.” (b) Approved maps. The appropriate maps for determining the boundary of the Arkansas...

  13. 27 CFR 9.102 - Sonoma Mountain.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Sonoma Mountain. 9.102... Sonoma Mountain. (a) Name. The name of the viticultural area described in this section is “Sonoma Mountain.” (b) Approved maps. The approved maps for determining the boundary of the Sonoma...

  14. 49 CFR 71.8 - Mountain zone.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 1 2012-10-01 2012-10-01 false Mountain zone. 71.8 Section 71.8 Transportation Office of the Secretary of Transportation STANDARD TIME ZONE BOUNDARIES § 71.8 Mountain zone. The fourth zone, the mountain standard time zone, includes that part of the United States that is west of...

  15. 27 CFR 9.94 - Howell Mountain.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Howell Mountain. 9.94... Howell Mountain. (a) Name. The name of the viticultural area described in this section is “Howell Mountain.” (b) Approved maps. The appropriate maps for determining the boundaries of the Howell...

  16. 27 CFR 9.94 - Howell Mountain.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Howell Mountain. 9.94... Howell Mountain. (a) Name. The name of the viticultural area described in this section is “Howell Mountain.” (b) Approved maps. The appropriate maps for determining the boundaries of the Howell...

  17. 27 CFR 9.112 - Arkansas Mountain.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Arkansas Mountain. 9.112... Arkansas Mountain. (a) Name. The name of the viticultural area described in this section is “Arkansas Mountain.” (b) Approved maps. The appropriate maps for determining the boundary of the Arkansas...

  18. 49 CFR 71.8 - Mountain zone.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 1 2013-10-01 2013-10-01 false Mountain zone. 71.8 Section 71.8 Transportation Office of the Secretary of Transportation STANDARD TIME ZONE BOUNDARIES § 71.8 Mountain zone. The fourth zone, the mountain standard time zone, includes that part of the United States that is west of...

  19. 27 CFR 9.94 - Howell Mountain.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Howell Mountain. 9.94... Howell Mountain. (a) Name. The name of the viticultural area described in this section is “Howell Mountain.” (b) Approved maps. The appropriate maps for determining the boundaries of the Howell...

  20. 27 CFR 9.102 - Sonoma Mountain.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Sonoma Mountain. 9.102... Sonoma Mountain. (a) Name. The name of the viticultural area described in this section is “Sonoma Mountain.” (b) Approved maps. The approved maps for determining the boundary of the Sonoma...

  1. 27 CFR 9.112 - Arkansas Mountain.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Arkansas Mountain. 9.112... Arkansas Mountain. (a) Name. The name of the viticultural area described in this section is “Arkansas Mountain.” (b) Approved maps. The appropriate maps for determining the boundary of the Arkansas...

  2. 27 CFR 9.102 - Sonoma Mountain.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Sonoma Mountain. 9.102... Sonoma Mountain. (a) Name. The name of the viticultural area described in this section is “Sonoma Mountain.” (b) Approved maps. The approved maps for determining the boundary of the Sonoma...

  3. 49 CFR 71.8 - Mountain zone.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Mountain zone. 71.8 Section 71.8 Transportation Office of the Secretary of Transportation STANDARD TIME ZONE BOUNDARIES § 71.8 Mountain zone. The fourth zone, the mountain standard time zone, includes that part of the United States that is west of...

  4. 27 CFR 9.112 - Arkansas Mountain.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Arkansas Mountain. 9.112... Arkansas Mountain. (a) Name. The name of the viticultural area described in this section is “Arkansas Mountain.” (b) Approved maps. The appropriate maps for determining the boundary of the Arkansas...

  5. 27 CFR 9.94 - Howell Mountain.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Howell Mountain. 9.94... Howell Mountain. (a) Name. The name of the viticultural area described in this section is “Howell Mountain.” (b) Approved maps. The appropriate maps for determining the boundaries of the Howell...

  6. 49 CFR 71.8 - Mountain zone.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 1 2011-10-01 2011-10-01 false Mountain zone. 71.8 Section 71.8 Transportation Office of the Secretary of Transportation STANDARD TIME ZONE BOUNDARIES § 71.8 Mountain zone. The fourth zone, the mountain standard time zone, includes that part of the United States that is west of...

  7. 27 CFR 9.102 - Sonoma Mountain.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Sonoma Mountain. 9.102... Sonoma Mountain. (a) Name. The name of the viticultural area described in this section is “Sonoma Mountain.” (b) Approved maps. The approved maps for determining the boundary of the Sonoma...

  8. 49 CFR 71.8 - Mountain zone.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 1 2014-10-01 2014-10-01 false Mountain zone. 71.8 Section 71.8 Transportation Office of the Secretary of Transportation STANDARD TIME ZONE BOUNDARIES § 71.8 Mountain zone. The fourth zone, the mountain standard time zone, includes that part of the United States that is west of...

  9. Effects of Landfall Location and Approach Angle of an Idealized Tropical Cyclone over a Long Mountain Range

    NASA Astrophysics Data System (ADS)

    Liu, Liping; Lin, Yuh-Lang; Chen, Shu-Hua

    2016-02-01

    Effects of landfall location and approach angle on track deflection associated with a tropical cyclone (TC) passing over an idealized and Central Appalachian Mountain is investigated by a series of idealized numerical experiments. When the TC landfalls on the central portion of the mountain range, it is deflected to the south upstream, passes over the mountain anticyclonically, and then moves westward downstream. The TC motion is steered by the positive vorticity tendency (VT) which is dominated by horizontal vorticity advection upstream and downstream, but with additional influence from the stretching and residual terms, which are mainly associated with diabatic heating and frictional effects. The track deflection mechanism upstream and downstream is similar to the dry flow in previous study, but is very different in the vicinity of the mountain. When the TC landfalls near the northern (southern) tip, it experiences less (more) southward deflection due to stronger (weaker) vorticity advection around the tip. When the TC approaches the mountain range from the southeast and landfalls on the northern tip, center, or southern tip, the track deflections are similar to those embedded in an easterly flow but with weaker orographic blocking. These results are similar to the cases simulated in the dry flow in previous study, except that there is no track discontinuity due to the weaker orographic blocking associated with strong TC convection. When a TC moves along the north-south mountain range from the south, it tends to deflect toward the mountain and then crosses over to the other side at later time. In these cases, the positive VT is influenced by all horizontal vorticity advection, vorticity stretching (diabatic heating) and residual (friction) terms due to longer and stronger interaction with the mountain range. The vorticity stretching is mainly caused by diabatic heating in the moist flow, instead of by lee slope vorticity stretching in the previous study for dry

  10. Anatomy of a Mountain Range.

    ERIC Educational Resources Information Center

    Chew, Berkeley

    1993-01-01

    Provides written tour of Colorado Rockies along San Juan Skyway in which the geological features and formation of the mountain range is explored. Discusses evidence of geologic forces and products such as plate tectonic movement and the Ancestral Rockies; subduction and the Laramide Orogeny; volcanism and calderas; erosion, faulting, land…

  11. Lone Mountain processing boosts recovery

    SciTech Connect

    Baumgarth, T.; Bethell, P.; Gupta, B.K.

    2005-08-01

    A new deslime column flotation circuit installed at Arch Coal's Lone Mountain preparation plant in St. Charles, Va., USA recovers an additional 20 tph. The article describes how this column technology was selected. It explains the circuit design, start-up and post upgrade distant testing. 4 figs., 4 tabs.

  12. Artifical Mountains: A Synthetic Approach

    ERIC Educational Resources Information Center

    Sipiera, Paul P.; Aumann, John A.

    1974-01-01

    Describes a secondary science unit which uses an urban environment to develop a comparison between naturally formed mountains and man-constructed skyscrapers. The unit is one in a series of fifty laboratory activities designed to stimulate students of earth science by interrelating scientific principles and procedures to a familiar environment.…

  13. Gearing Up for Mountain Biking.

    ERIC Educational Resources Information Center

    Jahnke, Thomas; Hamson, Mike

    1999-01-01

    Examines the gear system of a mountain bike to discover any redundancy in the many gear settings available to the cyclist. Suggests a best strategy for changing up through the gears on a typical 21-gear system and an adjustment to the available gears that would result in a smoother change. (Author/ASK)

  14. The Mountaineer-Malaysia Connection.

    ERIC Educational Resources Information Center

    Young, Jeff

    1997-01-01

    A 26-day summer field course of West Virginia University's (WVU) Recreation and Parks Department took students to Malaysia's mountains and rainforests to observe how Malaysians are managing national parks, problem elephants, and population pressures on parks. The adventure provided powerful learning experiences. Further exchanges between WVU and…

  15. FACING NORTHEAST ACROSS NORTHERN END OF PARK TOWARDS ITS NORTHERN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    FACING NORTHEAST ACROSS NORTHERN END OF PARK TOWARDS ITS NORTHERN CORNER - Candler Park Historic District, Roughly bounded by Moreland, Dekalb, McLendon & Harold Avenues, Matthews Street & Clifton Terrace, Atlanta, Fulton County, GA

  16. Continental margin evolution of the northern Arabian platform in Syria

    SciTech Connect

    Best, J.A.; Barazangi, M. ); Al-Saad, D.; Sawaf, T.; Gebran, A. )

    1993-02-01

    Synthesis of available geological and geophysical data in the Syrian Arab Republic permits a descriptive account of the pre-Cenozoic geologic history of the northern Arabian platform. The northern Arabian platform appears to be a composite plate similar up to that interpreted in the rocks of the Arabian shield. The structural and stratigraphic relationships of the Paleozoic and Mesozoic sedimentary sections in Syria record the transformation of an eastward-facing Gondwana passive margin in the early Paleozoic into a westward-facing Levantine margin in the Mesozoic, at which time the northern platform was closely associated with the creation of the eastern Mediterranean basin. Timing of the margin transformation is inferred from the orientation and thickness variations of Lower Triassic rocks, but the transformation may have initiated as early as the Permian. The diversity and timing of geological features in Syria suggest that the northern Arabian platform did not behave as a rigid plate throughout its geological history. The present-day Palmyride mountain belt, located within the northern Arabian platform in Syria and initiated in the early Mesozoic as a northeast-trending rift nearly perpendicular to the Levantine margin, subsequently was inverted in the Cenozoic by transpression. The location of the rift may be associated with the reactivation of a zone of crustal weakness, i.e., a Proterozoic suture zone previously proposed from modeling of Bouguer gravity data. Thus, the northern and southern parts of the Arabian platform are similar in their respective geologic histories during the Proterozoic and Paleozoic; however, the northern Arabian platform was greatly affected by Mesozoic rifting and the creation of the eastern Mediterranean basin during the Mesozoic. 13 figs.

  17. Miocene calc-alkaline magmatism, calderas, and crustal extension in the Kofa and Castle Dome Mountains, southwestern Arizona

    SciTech Connect

    Grubensky, M.J. ); Bagby, W.C. )

    1990-11-10

    Two widespread lower Miocene rhyolite ash flow tuffs in the Kofa and Castle Dome Mountains of southwestern Arizona are products of caldera-forming eruptions. These closely erupted tuffs, the tuff of Yaqui Tanks and the tuff of Ten Ewe Mountain, are approximately 22 Ma in age and their eruptions culminate a 1- to 2-m.y.-long burst of calc-alkaline volcanic activity centered on the northern Castle Dome Mountains. Exotic blocks of Proterozoic and Mesozoic crystalline rocks up to 20 m across are present in exposures of the tuff of Yaqui Tanks exposed in the central Castle Dome Mountains and the southern Kofa Mountains. A single, thick cooling unit of the tuff of Ten Ewe Mountain that includes thick lenses of mesobreccia marks the location of the younger caldera that extends from Palm Canyon in the western Kofa Mountains eastward more than 7 km along strike to the central part of the range. Large residual Bouguer gravity anomalies, one beneath each inferred caldera, are interpreted as batholithic rocks or low-density caldera fill. Caldera-related volcanism in the Kofa region occurred during a transition in extensional tectonic regimes: From a regime of east-west trending uplifts and basins to a regime manifest primarily by northwest striking normal faults. A narrow corridor of folding and strike-slip faulting formed during volcanism in the southern Kofa Mountains. Upper Oligocene or lower Miocene coarse sedimentary rocks along the southern flank of the Chocolate Mountains anticlinorium in the southern Castle Dome Mountains mark the periphery of a basin similar to other early and middle Tertiary basins exposed in southern California. The volcanic section of the Kofa region was dissected by high-angle normal faults related to northeast-southwest oriented crustal extension typical of the southern Basin and Range province.

  18. Cenozoic stratigraphy of the Sahara, Northern Africa

    USGS Publications Warehouse

    Swezey, Christopher S.

    2009-01-01

    This paper presents an overview of the Cenozoic stratigraphic record in the Sahara, and shows that the strata display some remarkably similar characteristics across much of the region. In fact, some lithologies of certain ages are exceptionally widespread and persistent, and many of the changes from one lithology to another appear to have been relatively synchronous across the Sahara. The general stratigraphic succession is that of a transition from early Cenozoic carbonate strata to late Cenozoic siliciclastic strata. This transition in lithology coincides with a long-term eustatic fall in sea level since the middle Cretaceous and with a global climate transition from a Late Cretaceous–Early Eocene “warm mode” to a Late Eocene–Quaternary “cool mode”. Much of the shorter-term stratigraphic variability in the Sahara (and even the regional unconformities) also can be correlated with specific changes in sea level, climate, and tectonic activity during the Cenozoic. Specifically, Paleocene and Eocene carbonate strata and phosphate are suggestive of a warm and humid climate, whereas latest Eocene evaporitic strata (and an end-Eocene regional unconformity) are correlated with a eustatic fall in sea level, the build-up of ice in Antarctica, and the appearance of relatively arid climates in the Sahara. The absence of Oligocene strata throughout much of the Sahara is attributed to the effects of generally low eustatic sea level during the Oligocene and tectonic uplift in certain areas during the Late Eocene and Oligocene. Miocene sandstone and conglomerate are attributed to the effects of continued tectonic uplift around the Sahara, generally low eustatic sea level, and enough rainfall to support the development of extensive fluvial systems. Middle–Upper Miocene carbonate strata accumulated in northern Libya in response to a eustatic rise in sea level, whereas Upper Miocene mudstone accumulated along the south side of the Atlas Mountains because uplift of the

  19. Quantity and location of groundwater recharge in the Sacramento Mountains, south-central New Mexico (USA), and their relation to the adjacent Roswell Artesian Basin

    NASA Astrophysics Data System (ADS)

    Rawling, Geoffrey C.; Newton, B. Talon

    2016-06-01

    The Sacramento Mountains and the adjacent Roswell Artesian Basin, in south-central New Mexico (USA), comprise a regional hydrologic system, wherein recharge in the mountains ultimately supplies water to the confined basin aquifer. Geologic, hydrologic, geochemical, and climatologic data were used to delineate the area of recharge in the southern Sacramento Mountains. The water-table fluctuation and chloride mass-balance methods were used to quantify recharge over a range of spatial and temporal scales. Extrapolation of the quantitative recharge estimates to the entire Sacramento Mountains region allowed comparison with previous recharge estimates for the northern Sacramento Mountains and the Roswell Artesian Basin. Recharge in the Sacramento Mountains is estimated to range from 159.86 × 106 to 209.42 × 106 m3/year. Both the location of recharge and range in estimates is consistent with previous work that suggests that ~75 % of the recharge to the confined aquifer in the Roswell Artesian Basin has moved downgradient through the Yeso Formation from distal recharge areas in the Sacramento Mountains. A smaller recharge component is derived from infiltration of streamflow beneath the major drainages that cross the Pecos Slope, but in the southern Sacramento Mountains much of this water is ultimately derived from spring discharge. Direct recharge across the Pecos Slope between the mountains and the confined basin aquifer is much smaller than either of the other two components.

  20. Quantity and location of groundwater recharge in the Sacramento Mountains, south-central New Mexico (USA), and their relation to the adjacent Roswell Artesian Basin

    NASA Astrophysics Data System (ADS)

    Rawling, Geoffrey C.; Newton, B. Talon

    2016-04-01

    The Sacramento Mountains and the adjacent Roswell Artesian Basin, in south-central New Mexico (USA), comprise a regional hydrologic system, wherein recharge in the mountains ultimately supplies water to the confined basin aquifer. Geologic, hydrologic, geochemical, and climatologic data were used to delineate the area of recharge in the southern Sacramento Mountains. The water-table fluctuation and chloride mass-balance methods were used to quantify recharge over a range of spatial and temporal scales. Extrapolation of the quantitative recharge estimates to the entire Sacramento Mountains region allowed comparison with previous recharge estimates for the northern Sacramento Mountains and the Roswell Artesian Basin. Recharge in the Sacramento Mountains is estimated to range from 159.86 × 106 to 209.42 × 106 m3/year. Both the location of recharge and range in estimates is consistent with previous work that suggests that ~75 % of the recharge to the confined aquifer in the Roswell Artesian Basin has moved downgradient through the Yeso Formation from distal recharge areas in the Sacramento Mountains. A smaller recharge component is derived from infiltration of streamflow beneath the major drainages that cross the Pecos Slope, but in the southern Sacramento Mountains much of this water is ultimately derived from spring discharge. Direct recharge across the Pecos Slope between the mountains and the confined basin aquifer is much smaller than either of the other two components.

  1. 30. NORTHERN SEGMENT OF THE LATERAL IN THE NORTHWEST QUARTER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    30. NORTHERN SEGMENT OF THE LATERAL IN THE NORTHWEST QUARTER OF SECTION 25 STRUCTURE PICTURED IN CO-43-A-28. - Highline Canal, Sand Creek Lateral, Beginning at intersection of Peoria Street & Highline Canal in Arapahoe County (City of Aurora), Sand Creek lateral Extends 15 miles Northerly through Araphoe County, City & County of Denver, & Adams County to its end point, approximately 1/4 mile Southest of intersectioin of D Street & Ninth Avenue in Adams County (Rocky Mountain Arsenal, Commerce City Vicinity), Commerce City, Adams County, CO

  2. Late Quaternary tectonic activity and crustal shortening rate of the Bogda mountain area, eastern Tian Shan, China

    NASA Astrophysics Data System (ADS)

    Wu, Chuanyong; Wu, Guodong; Shen, Jun; Dai, Xunye; Chen, Jianbo; Song, Heping

    2016-04-01

    The Bogda mountain range is the highest range among the northern Tian Shan mountains. Based on geologic and geomorphologic field surveys, trench excavation and optically stimulated luminescence (OSL) dating, we targeted the active Fukang fault along the Bogda mountain range and identified the late Quaternary deformation characteristics of this area. We found that the Fukang fault dislocated different geomorphic surfaces of the northern Bogda piedmont. The vertical fault displacement corresponds to the topographic relief of the Bogda over long time scales. Since the late Quaternary, the crustal shortening rate was estimated to be 0.90 ± 0.20 mm/yr, which is less than that of the western segment of the northern Tian Shan. We interpret the Bogda fold and thrust belt to be a thick-skinned structure, since a high angle thrust fault bounds the Bogda mountain range and the foreland basin. The deformation characteristics of this region have been dominated by vertical uplift, and the component of propagation toward the basin has been very limited. This tectonic deformation is evidenced as vertical growth. Although the deformation rate is small, the uplift amplitude is very significant in this region.

  3. Best Practices Case Study: Pine Mountain Builders - Pine Mountain, GA

    SciTech Connect

    2011-09-01

    Case study of Pine Mountain Builders who worked with DOE’s IBACOS team to achieve HERS scores of 59 on 140 homes built around a wetlands in Georgia. The team used taped rigid foam exterior sheathing and spray foam insulation in the walls and on the underside of the attic for a very tight 1.0 to 1.8 ACH 50 building shell.

  4. A tunnel runs through it: an inside view of the Tualatin Mountains, Oregon

    USGS Publications Warehouse

    Walsh, Ken; Peterson, Gary L.; Beeson, Marvin H.; Wells, Ray E.; Fleck, Robert J.; Evarts, Russell C.; Duvall, Alison; Blakely, Richard J.; Burns, Scott

    2011-01-01

    The Tualatin Mountains form a northwest-striking ridge about 350 m high that separates Portland, Oregon, from the cities of the Tualatin Valley to the west. Known informally as the Portland Hills, the ridge is a late Cenozoic anticline, bounded by reverse faults that dip toward the anticlinal axis. The anticline is a broad, open fold consisting chiefly of Miocene Columbia River Basalt Group, with remnants of Miocene-Pliocene Troutdale Formation and Pleistocene basalt of the Boring Volcanic Field on the flanks of the anticline. Anticlinal structures similar to the Tualatin Mountains are characteristic of the northern Willamette Valley, where the structures accommodate margin-parallel shortening of the Cascadia fore arc. Global Positioning System (GPS) results indicate that the shortening is due to the northward motion of Oregon at several millimeters per year with respect to stable North America. Some of the uplifts may contain active faults, but the structures are poorly exposed and are overlain by thick Pleistocene loess and Missoula flood deposits. Between 1993 and 1998, construction of the 3-mile-long (4500-m-long) TriMet MAX Light Rail tunnel through the Tualatin Mountains provided an unusual opportunity to investigate the geological structure and history of the Tualatin Mountains. This report is a collaborative effort among the tunnel geologists and the U.S. Geological Survey (USGS) to document the geologic story and quantify late Cenozoic and Quaternary deformation rates of the Tualatin Mountains.

  5. Bedrock geologic map of the Yucca Mountain area, Nye County, Nevada

    SciTech Connect

    Day, W.C.; Potter, C.J.; Sweetkind, D.S.; Fridrich, C.J.; Dickerson, R.P.; San Juan, C.A.; Drake, R.M. II

    1998-11-01

    Yucca Mountain, Nye County, Nevada, has been identified as a potential site for underground storage of high-level radioactive nuclear waste. Detailed bedrock geologic maps form an integral part of the site characterization program by providing the fundamental framework for research into the geologic hazards and hydrologic behavior of the mountain. This bedrock geologic map provides the geologic framework and structural setting for the area in and adjacent to the site of the potential repository. The study area comprises the northern and central parts of Yucca Mountain, located on the southern flank of the Timber Mountain-Oasis Valley caldera complex, which was the source for many of the volcanic units in the area. The Timber Mountain-Oasis Valley caldera complex is part of the Miocene southwestern Nevada volcanic field, which is within the Walker Lane belt. This tectonic belt is a northwest-striking megastructure lying between the more active Inyo-Mono and Basin-and-Range subsections o f the southwestern Great Basin.

  6. Ice in the northern plains: Relic of a frozen ocean?

    NASA Technical Reports Server (NTRS)

    Lucchitta, B. K.

    1993-01-01

    Viking images revealed many features in the northern plains and along their boundary that early investigators believed to be formed by ice-related processes. The features are possible pingos, pseudocraters, table mountains and moberg ridges, thermokarst depressions, moraines, patterned ground, and lobate aprons that suggest viscous flow such as that of ice or rock glaciers. More recently, many of these features were reinterpreted as related to sedimentation in hypothetical former polar lakes, oceans, or alluvial plains or as shoreline features of associated water bodies. Some evidence that points toward the existence of former bodies of standing water in the northern plains, but is also consistent with the idea that these bodies were ice covered or completely frozen is reviewed.

  7. Late Wisconsinan ice sheet flow across northern and central Vermont, USA

    NASA Astrophysics Data System (ADS)

    Wright, Stephen F.

    2015-12-01

    A compilation of over 2000 glacial striation azimuths across northern and central Vermont, northeastern USA, provides the basis for interpreting a sequence of ice flow directions across this area. The oldest striations indicate widespread ice flow to the southeast, obliquely across the mountains. Similarly oriented striations between northern Vermont and the ice sheet's terminus in the Gulf of Maine suggest that a broad area of southeast ice flow existed at the Last Glacial Maximum. Younger striations with more southerly azimuths on both the mountain ridgelines and within adjacent valleys indicate that ice sheet flow trajectories in most areas rotated from southeast to south, parallel to the North-South alignment of the mountains, as the ice sheet thinned. This transition in ice flow direction was time transgressive from south to north with the Green Mountains eventually separating a thick south-flowing lobe of ice in the Champlain Valley from a much thinner lobe of south-flowing ice east of the mountains. While this transition was taking place yet ice was still thick enough to flow across the mountains, ice flow along a narrow ˜65 km long section of the Green Mountains shifted to the southwest such that ice was flowing into the Champlain Valley. The most likely process driving this change was a limited period of fast ice flow in the Champlain Valley, a short-lived ice streaming event, that drew down the ice surface in the valley. The advancing ice front during this period of fast ice flow may be responsible for the Luzerne Readvance south of Glens Falls, New York. Valley-parallel striations across the area indicate strong topographic control on ice flow as the ice sheet thinned.

  8. Modeling differentiation of Karaj Dam basement igneous rocks (northern Iran)

    NASA Astrophysics Data System (ADS)

    Esmaeily, D.; M-Mashhour, R.

    2009-04-01

    The Karaj Dam basement igneous body (KDB) is located in the north of city of Karaj, 30 km from city of Tehran, which lies between 35° 50' N to 36° 05' N and between 50° 50' E to 51° 15' E. It is one of the several plutonic bodies within the E-W trending Alborz zone in northern Iran. Following the late Cretaceous orogenic movements, vast volumes of dacite, andesites and basaltic lavas with tuffaceous and other clastic sediments were deposited during Eocene time, forming Karaj Formation in central Iran and Albourz. The KDB is penetrated thorough middle and upper tuff units from Karaj Formation which is underlain by late Jurassic depositions (Shemshak Formation) and overlain by the Neogene red Conglomerates in regard to stratographic consideration. It is mainly composed of a layered series dominated by gabbro, diorite and monzonite, which is a rock sequence formed upward from the lower to upper chilled margins, respectively. The chilled margins, which have gabbroic in composition, show porphyritic texture with euhedral to subhedral plagioclase (andesine & labradorite) and pyroxene (augite) megacrysts up to 5 mm long. These rocks become coarse-grained inward and transform to equigranular texture gradually.In addition, a small fine-grained doleritic stock as well as some doleritic dykes is intrusive into the pyroclastic volcanic rocks of Karaj Formation. It is possible to observe doleritic enclaves included in the KDB, indicating that the KDB are slightly younger than the dolerites. Whole rock geochemistry and mineral chemistry of the plagioclase and pyroxene in various rock samples, suggest differentiation processes. The Mg# of the pyroxene and An% of plagioclase of the contact chilled samples can be used as an indication of the original magma and plotted between the gabbro and monzonitic samples. In addition, increasing of the Mg# within the whole rock samples from the upper of contact chilled, in comparison to the lower one, demonstrates elemental differentiation

  9. Movements of northern flying squirrels in different-aged forest stands of western Oregon

    USGS Publications Warehouse

    Martin, K.J.; Anthony, R.G.

    1999-01-01

    In western Oregon, northern flying squirrels (Glaucomys sabrinus) are the primary prey species for northern spotted owls (Strix occidentalis caurina), an old-growth associated species. To assess differences between old-growth and second-growth habitat, we livetrapped and radiotagged 39 northern flying squirrels to estimate their home range sizes and describe movements in 2 old-growth and 2 second-growth conifer forest stands in the Cascade Mountains of central Oregon. Sampling periods were summer and fall of 1991-92. Home range sizes averaged 4.9 ha and did not differ (P > 0.30) between the 2 stand types. Male northern flying squirrels had larger (P ??? 0.03) mean home ranges (5.9 ?? 0.8 ha; ?? ?? SE; n = 20) than females (3.9 ?? 0.4 ha; n = 19). Northern flying squirrel movement distances between successive, noncorrelated telemetry locations averaged 71 m (n = 1,090). No correlation was found between distances moved and stand type or sex. Northern flying squirrel's home range sizes, movements, and densities were similar between the 2 stand types. We suggest abundance and movements of northern flying squirrels are not influencing the preferential selection of oldgrowth forests by northern spotted owls.

  10. Tectonic and igneous geology of the northern Shoshone Range, Nevada, with sections on gravity in Crescent Valley and economic geology

    USGS Publications Warehouse

    Gilluly, James; Gates, Olcott; Plouff, Donald; Ketner, K.B.

    1965-01-01

    Part of the northern Shoshone Range and its bordering valleys are shown in the Mount Lewis and Crescent Valley quadrangles of the U.S. Geological Survey's Topographic Atlas. A very small part of the Cortez Mountains extends into the Crescent Valley quadrangle and is also described.

  11. Lessons from a 5 yr citizen-science monitoring program, Mountain Watch, to engage hikers in air quality/visibility and plant phenology monitoring in the mountains

    NASA Astrophysics Data System (ADS)

    Murray, G.; Weihrauch, D.; Kimball, K.; McDonough, C.

    2010-12-01

    The AMC’s citizen scientist monitoring program, Mountain Watch, engages hikers in observational monitoring while recreating in the northern Appalachian Mountains. The program uses two monitoring activities:1) tracking the phenology of 11 mountain flowers species, and 2) the visitors real world perception of on-mountain visibility and its ‘quality’ with proximate monitored air quality parameters. The Mountain Watch program objectives are a) to engage and educate the public through hands-on monitoring, b) to motivate the participant to take further action towards environmental stewardship, and c) to provide supplemental data to AMC’s ongoing science-based research to further our understanding of the impact of human activity on mountain ecosystems. The Mountain Watch plant monitoring includes recording the time and location of alpine and forest plants flowering and other phenological phases using AMC field guides and datasheets. In the White Mountains of New Hampshire concurrent meteorological data, including soil temperature, is paired with the phenology observations as part of AMC’s research to develop spatial and temporal phenology models with air and soil temperature for northeastern mountains. Mountain Watch’s visibility monitoring program has hikers record visual range and rate the view at select vistas in comparison to a clear day view photo guide when visiting AMC’s backcountry huts. The results are compared to proximate air quality measurements, which assists in determining how White Mountain National Forest air quality related values and natural resources management objectives are being met. Since 2006 the Mountain Watch program has received over 3,500 citizen datasheets for plant reproductive phenology and visibility monitoring. We estimate that we have reached more than 15,000 hikers through our facility based education programming focused on air quality and phenology and field monitoring hikes. While we consider this good success in engaging

  12. A numerical study of the acid rain in northern Taiwan in winter season

    SciTech Connect

    Chen, Ching-Sen; Deng, Zen-Sing

    1996-12-31

    Two-thirds of the land mass of Taiwan island is covered by mountains. In winter precipitation could occur in northern Taiwan when the prevailing wind was from northeastern direction. In northern Taiwan the acid rain (pH value less than 5.0) in winter time could contribute about 30 rain in the whole year. A three-dimensional numerical model with terrain following coordinated system was used to simulate the precipitation system and the characteristics of acid rain. A smooth terrain was assumed in the model. A mean sounding was used to initialize the numerical model when acid rain occurred in northern Taiwan during winter time from 1991 to 1993. Investigations of the effect of pollutions from abroad on the acid rain in northern Taiwan in winter are considered for the future.

  13. Microbial activity at Yucca Mountain

    SciTech Connect

    Horn, J.M.; Meike, A.

    1995-09-25

    The U.S. Department of Energy is engaged in a suitability study for a potential geological repository at Yucca Mountain, Nevada, for the containment and storage of commercially generated spent fuel and defense high-level nuclear waste. There is growing recognition of the role that biotic factors could play in this repository, either directly through microbially induced corrosion (MIC), or indirectly by altering the chemical environment or contributing to the transport of radionuclides. As a first step toward describing and predicting these processes, a workshop was held on April 10-12, 1995, in Lafayette, California. The immediate aims of the workshop were: (1) To identify microbially related processes relevant to the design of a radioactive waste repository under conditions similar to those at Yucca Mountain. (2) To determine parameters that are critical to the evaluation of a disturbed subterranean environment. (3) To define the most effective means of investigating the factors thus identified.

  14. Recompression therapy of mountain sickness.

    PubMed

    Marković, Dubravko; Kovacević, Hasan

    2002-03-01

    This paper describes the treatment of a severe case of acute mountain sickness with a portable hyperbaric chamber. A 37-year old climber was treated for acute high altitude pulmonary oedema, which developed on the North Col of Mount Everest, at an altitude of 7,060 m. The treatment in the portable Gamow bag hyperbaric chamber lasted two hours, with a bag pressure of 103 mm Hg (0.136 kg/cm2 or 2 psig) using ambient air, without the addition of oxygen. With this pressure increase, the hyperbaric chamber lowered the patient's effective ambient altitude from 6,050 to 4,400 m. The treatment was successful and the pulmonary oedema disappeared. Outside the hyperbaric chamber, the patient recovered fully when he reached the altitude of 2,000 m. Portable hyperbaric chamber is recommended for the treatment of severe cases of acute mountain sickness, as well as for risky descent to lower altitudes. PMID:12150075

  15. Overprinting deformations in mantle rocks of Dun Mountain, New Zealand

    NASA Astrophysics Data System (ADS)

    Donnelly, S.; Newman, J.; Lamb, W. M.; Tikoff, B.

    2013-12-01

    Dun Mountain is the northern-most of three well-exposed ultramafic massifs in the Dun Mountain Ophiolite Belt (DMOB), South Island, New Zealand. The Dun Mountain massif is characterized by dunite and harzburgite compositional bands ranging in thickness from 1 cm to 1 m. Despite its compositional and structural simplicity relative to the other DMOB ultramafic bodies, microstructures at Dun Mountain preserve evidence for overprinting deformations. Olivine appears in bi- and tri-modal grain size distributions and olivine grains exhibit undulose extinction and subgrains. Pyroxenes exhibit exsolution lamellae and acute angles that partially surround olivine, spinel, and/or other pyroxene grains. Intermediate-sized olivine and pyroxene grains occur in microscale compositional bands with straight grain boundaries coincident with compositional boundaries. Grain size analyses were carried out using the mean lineal intercept method with Spektor's chord analysis, and stresses are estimated using the experimentally derived grain size piezometer. Three distinct grain size populations are resolved. The coarse olivine grains have an average chord length of 5.0 mm corresponding to a stress of 2 MPa. The coarse olivine grains have no microstructurally equivalent pyroxenes; for rheologic estimates, pressure (P) and temperature (T) from the intermediate grain compositions are assumed to reflect a minimum P and T for the coarse population. The intermediate grain size population has an average chord length of 1.8 mm, yielding a stress of ~5 MPa. Geothermometry (estimated from compositions of coexisting pyroxenes) yields a temperature of ~1130 °C at a mimimum pressure of 600 MPa. The finest grain size population has an average chord length of 0.4 mm with stress ~ 15 MPa, and geothermometry yields T ≈ 950 °C, at a minimum P of 550 MPa. Image analysis indicates an olivine shape-preferred orientation with axial ratio of 1.9:1, subparallel to the harzburgite/dunite foliation measured in

  16. Holocene glacier activity in the British Columbia Coast Mountains, Canada

    NASA Astrophysics Data System (ADS)

    Mood, Bryan J.; Smith, Dan J.

    2015-11-01

    The Coast Mountains flank the Pacific Ocean in western British Columbia, Canada. Subdivided into the southern Pacific Ranges, central Kitimat Ranges and northern Boundary Ranges, the majority of large glaciers and icefields are located in the Boundary and Pacific ranges. Prior descriptions of the Holocene glacial history of this region indicate the Holocene was characterized by repeated episodes of ice expansion and retreat. Recent site-specific investigations augment our understanding of the regional character and duration of these events. In this paper, previously reported and new radiocarbon evidence is integrated to provide an updated regional assessment. The earliest evidence of glacier expansion in the Coast Mountains comes from the Boundary Ranges at 8.9 and 7.8 ka and in the Pacific Ranges at 8.5-8.2 ka, with the latter advance corresponding to an interval of rapid, global climate deterioration. Although generally warm and dry climates from 7.3 to 5.3 ka likely limited the size of glaciers in the region, there is radiocarbon evidence for advances over the interval from 7.3 to 6.0 and at 5.4-5.3 ka in the Pacific Ranges. Following these advances, glaciers in the Pacific Ranges expanded down valley at 4.8-4.6, 4.4-4.0, 3.5-2.6, 1.4-1.2, and 0.8-0.4 ka, while glaciers in Boundary Ranges were advancing at 4.1-4.0, 3.7-3.4, 3.1-2.8, 2.3, 1.7-1.1, and 0.8-0.4 ka. After 0.4 ka, it appears that most glaciers in the Coast Mountains continued to expand to attain their maximum Holocene extents by the early 18th to late 19th centuries. This enhanced record of Holocene glacier activity highlights the temporal synchrony in the Coast Mountains. Individual expansion events in the mid-to late Holocene broadly correspond to intervals of regional glacier activity reported in the Canadian Rocky Mountains, in Alaska, and on high-elevation volcanic peaks in Washington State.

  17. Timescales of orogeny: Jurassic construction of the Klamath Mountains

    NASA Astrophysics Data System (ADS)

    Hacker, Bradley R.; Donato, Mary M.; Barnes, Calvin G.; McWilliams, M. O.; Ernst, W. G.

    1995-06-01

    An electronic supplement of this material may be obtained on a diskette or Anonymous FTP from KOSMOS.AGU.ORG (LOGIN to AGU's FTP account using ANONYMOUS as the username and GUEST as the password. Go to the right directory by typing CD APEND. Type LS to see what files are available. Type GET and the name of the file to get it. Finally, type EXIT to leave the system.) (Paper 94YCJ2454, Timescales of orogeny: Jurassic construction of the Klamath Mountains, B.R. Hacker, M.M. Donato, C.G. Barnes, M.O. McWilliams, and W.G. Ernst). Diskette may be ordered from American Geophysical Union, 2000 Florida Avenue, N.W., Washington, DC 20009; $15.00. Payment must accompany order. Classical interpretations of orogeny were based on relatively imprecise biostratigraphic and isotopic age determinations that necessitated grouping apparently related features that may in reality have been greatly diachronous. Isotopic age techniques now have the precision required to resolve the timing of orogenic events on a scale much smaller than that of entire mountain belts. Forty-five new 40Ar/39Ar ages from the Klamath Mountains illuminate the deformation, metamorphism, magmatism, and sedimentation involved in the Jurassic construction of that orogen, leading to a new level of understanding regarding how preserved orogenic features relate to ancient plate tectonic processes. The new geochronologic relationships show that many Jurassic units of the Klamath Mountains had 200 Ma or older volcanoplutonic basement. Subsequent formation of a large ˜170 Ma arc was followed by contractional collapse of the arc. Collision with a spreading ridge may have led to large-scale NW-SE extension in the central and northern Klamaths from 167 to ˜155 Ma, coincident with the crystallization of voluminous plutonic and volcanic suites. Marked cooling of a large region of the central Klamath Mountains to below ˜350°C at ˜150 Ma may have occurred as the igneous belt was extinguished by subduction of colder

  18. Spatial patterns in forest composition and standing dead red spruce in montane forests of the Adirondacks and northern Appalachians.

    PubMed

    Craig, B W; Friedland, A J

    1991-08-01

    The decline of red spruce (Picea rubens Sarg.) in montane forests of the northeastern United States has been previously reported. The objective of this study was to assess spatial patterns, if any, in standing dead red spruce stems in the Adirondacks of New York and northern Appalachians of Vermont, New Hampshire, and Maine. A stratified random sample of 19 mountains along a west to east transect in the Adirondacks and the northern Appalachians showed that the live basal area of all species was highest in the White Mountains (34.6 m(2) ha(-1)) and lowest in the Adirondack Mountains (23.7 m(2) ha(-1)) in the Green Mountains was significantly lower than in any other region. Intact standing dead red spruce in the Adirondack and Green Mountains (30%) was significantly higher than that in the three eastern clusters (14%). The amount of intact standing dead red spruce trees increased with elevation in only the western part of the region. With the exception of the Adirondacks, there was a greater average percent dead red spruce on the west side than on the east side of each mountain. The sum of standing dead for other tree species (average 13%) showed no statistically significant patterns with region, elevation or aspect, and was significantly lower than the amount of total dead red spruce (average 42%). The standing dead red spruce patterns we observed cannot be associated with any specific causal factors at this time. PMID:24233751

  19. Rocky Mountain snowpack chemistry network; history, methods, and the importance of monitoring mountain ecosystems

    USGS Publications Warehouse

    Ingersoll, George P.; Turk, John T.; Mast, M. Alisa; Clow, David W.; Campbell, Donald H.; Bailey, Zelda C.

    2002-01-01

    Because regional-scale atmospheric deposition data in the Rocky Mountains are sparse, a program was designed by the U.S. Geological Survey to more thoroughly determine the quality of precipitation and to identify sources of atmospherically deposited pollution in a network of high-elevation sites. Depth-integrated samples of seasonal snowpacks at 52 sampling sites, in a network from New Mexico to Montana, were collected and analyzed each year since 1993. The results of the first 5 years (1993?97) of the program are discussed in this report. Spatial patterns in regional data have emerged from the geographically distributed chemical concentrations of ammonium, nitrate, and sulfate that clearly indicate that concentrations of these acid precursors in less developed areas of the region are lower than concentrations in the heavily developed areas. Snowpacks in northern Colorado that lie adjacent to both the highly developed Denver metropolitan area to the east and coal-fired powerplants to the west had the highest overall concentrations of nitrate and sulfate in the network. Ammonium concentrations were highest in northwestern Wyoming and southern Montana.

  20. Micrometeorites from the Transantarctic Mountains

    PubMed Central

    Rochette, P.; Folco, L.; Suavet, C.; van Ginneken, M.; Gattacceca, J.; Perchiazzi, N.; Braucher, R.; Harvey, R. P.

    2008-01-01

    We report the discovery of large accumulations of micrometeorites on the Myr-old, glacially eroded granitic summits of several isolated nunataks in the Victoria Land Transantarctic Mountains. The number (>3,500) of large (>400 μm and up to 2 mm in size) melted and unmelted particles is orders of magnitudes greater than other Antarctic collections. Flux estimates, bedrock exposure ages and the presence of ≈0.8-Myr-old microtektites suggest that extraterrestrial dust collection occurred over the last 1 Myr, taking up to 500 kyr to accumulate based on 2 investigated find sites. The size distribution and frequency by type of cosmic spherules in the >200-μm size fraction collected at Frontier Mountain (investigated in detail in this report) are similar to those of the most representative known micrometeorite populations (e.g., South Pole Water Well). This and the identification of unusual types in terms of composition (i.e., chondritic micrometeorites and spherulitic aggregates similar to the ≈480-kyr-old ones recently found in Antarctic ice cores) and size suggest that the Transantarctic Mountain micrometeorites constitute a unique and essentially unbiased collection that greatly extends the micrometeorite inventory and provides material for studies on micrometeorite fluxes over the recent (≈1 Myr) geological past. PMID:19011091

  1. The hydrology of Yucca Mountain

    SciTech Connect

    Flint, A.L.; Flint, L.E.; Bodvarsson, G.S.; Kwicklis, E.M.; Fabryka-Martin, J.M.

    2000-12-04

    Yucca Mountain, located in southern Nevada in the Mojave Desert, is being considered as a geologic repository for high-level radioactive waste. Although the site is arid, previous studies indicate net infiltration rates of 5-10 mm yr(-1) under current climate conditions. Unsaturated flow of water through the mountain generally is vertical and rapid through the fractures of the welded tuffs and slow through the matrix of the nonwelded tuffs. The vitric-zeolitic boundary of the nonwelded tuffs below the potential repository, where it exists, causes perching and substantial lateral flow that eventually flows through faults near the eastern edge of the potential repository and recharges the underlying groundwater system. Fast pathways are located where water flows relatively quickly through the unsaturated zone to the water table. For the bulk of the water a large part of the travel time from land surface to the potential repository horizon (similar to 300 m below land surface) is through the interlayered, low fracture density, nonwelded tuff where flow is predominantly through the matrix. The unsaturated zone at Yucca Mountain is being modeled using a three-dimensional, dual-continuum numerical model to predict the results of measurements and observations in new boreholes and excavations. The interaction between experimentalists and modelers is providing confidence in the conceptual model and the numerical model and is providing researchers with the ability to plan further testing and to evaluate the usefulness or necessity of further data collection.

  2. Northern Meridiani Scene

    NASA Technical Reports Server (NTRS)

    2004-01-01

    19 November 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows eroded remnants of layered sedimentary rock in northern Sinus Meridiani. The layering is best seen in the circular feature at the center/right, which is an old meteor impact crater that was once filled and buried beneath the sedimentary rocks, then later exhumed and eroded to its present state. All of the sedimentary rocks exposed in this portion of northern Sinus Meridiani are probably older than the rocks in central Sinus Meridiani that have been examined this year by the Mars Exploration Rover, Opportunity. Like the rocks visited by the rover, these, too, may contain detailed clues regarding a wetter Mars in the distant past. These landforms are located near 6.0oN, 2.0oW. The image covers an area approximately 3 km (1.9 mi) wide. Sunlight illuminates the scene from the left/lower left.

  3. Geophysical studies in the vicinity of Blue Mountain and Pumpernickel Valley near Winnemucca, north-central Nevada

    USGS Publications Warehouse

    Ponce, David A.

    2012-01-01

    From May 2008 to September 2009, the U.S. Geological Survey (USGS) collected data from more than 660 gravity stations, 100 line-km of truck-towed magnetometer traverses, and 260 physical-property sites in the vicinity of Blue Mountain and Pumpernickel Valley, northern Nevada (fig. 1). Gravity, magnetic, and physical-property data were collected to study regional crustal structures as an aid to understanding the geologic framework of the Blue Mountain and Pumpernickel Valley areas, which in general, have implications for mineral- and geothermal-resource investigations throughout the Great Basin.

  4. Sierra Nevada Mountain Range as seen from STS-58

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The Sierra Nevada Mountain Range can be seen in this north-looking high oblique view taken in October, 1993, by the STS-58 crew. Visible in the view to the west of the Sierra Nevada are the San Joaquin and Sacramento Valleys of central California. The San Francisco/Oakland Bay Area can be seen to the west of the valley at the extreme left of the photograph. To the east or right of the Sierra Nevada, the basin and Range Region of central and northern Nevada is visible. Mono Lake, Lake Tahoe and Pyramid lake are also visible in this scene. The long northwest/southeast trending Walker Lane Shear Zone, which lies just to the east (right) of the Sierra Nevada is also visible. Near the top of the view (near the horizon), the snow covered volcanic peak Mount Shasta can be seen.

  5. Northern Plains Patterns

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-513, 14 October 2003

    Patterns are common on the northern plains of Mars. Like their terrestrial counterparts in places like Siberia, Alaska, and northern Canada, patterned ground on Mars might be an indicator of the presence of ground ice. Whether it is true that the patterns on Mars are related to ground ice and whether the ice is still present beneath the martian surface are unknown. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) picture shows an example of patterned ground on the martian northern plains near 72.4oN, 252.6oW. The dark dots and lines are low mounds and chains of mounds. The circular feature near the center of the image is the location of a buried meteor impact crater; its presence today is marked only by the dark boulders on its rim and ejecta blanket that have managed to remain uncovered at the martian surface. The area shown is 3 km (1.9 mi) wide and illuminated by sunlight from the lower left.

  6. PREFACE: Northern Eurasia Earth Science Partnership Initiative

    NASA Astrophysics Data System (ADS)

    Groisman, Pavel; Soja, Amber J.

    2009-12-01

    The Northern Eurasia Earth Science Partnership Initiative (NEESPI) was launched five years ago with the release of its Science Plan (http://neespi.org). Gradually, the Initiative was joined by numerous international projects and launched in the European Union, Russia, United States, Canada, Japan, and China. Currently, serving as an umbrella for more than 130 individual research projects (always with international participation) and with a 15M annual budget, this highly diverse initiative is in full swing. Since the first NEESPI focus issue (Pavel Groisman et al 2007 Environ. Res. Lett. 2 045008 (1pp)) in December 2007, several NEESPI Workshops and Sessions at International Meetings have been held that strengthen the NEESPI grasp on biogeochemical cycle and cryosphere studies, climatic and hydrological modeling, and regional NEESPI components in the Arctic, non- boreal Eastern Europe, Central Asia, northern Siberia, and mountainous regions of the NEESPI domain. In May 2009, an overview NEESPI paper was published in the Bulletin of the American Meteorological Society (BAMS) (Pavel Groisman et al 2009 Bull. Am. Met. Soc. 90 671). This paper also formulated a requirement to the next generation of NEESPI studies to work towards attaining a higher level of integration of observation programs, process studies, and modeling, across disciplines. Three books devoted to studies in different regions of Northern Eurasia prepared by the members of the NEESPI team have appeared and/or are scheduled to appear in 2009. This (second) ERL focus issue dedicated to climatic and environmental studies in Northern Eurasia is composed mostly from the papers that were presented at two NEESPI Open Science Sessions at the Annual Fall Meeting of the American Geophysical Union (December 2008, San Francisco, CA) and at the General Assembly of the European Geosciences Union (April 2009, Vienna, Austria), as well as at the specialty NEESPI Workshops convened in Jena, Helsinki, Odessa, Urumqi

  7. Mountain hemlock growth responds to climatic variability at annual and decadal time scales

    USGS Publications Warehouse

    Peterson, D.W.; Peterson, D.L.

    2001-01-01

    Improved understanding of tree growth responses to climate is needed to model and predict forest ecosystem responses to current and future climatic variability. We used dendroecological methods to study the effects of climatic variability on radial growth of a subalpine conifer, mountain hemlock (Tsuga mertensiana). Tree-ring chronologies were developed for 31 sites, spanning the latitudinal and elevational ranges of mountain hemlock in the Pacific Northwest. Factor analysis was used to identify common patterns of inter-annual growth variability among the chronologies, and correlation and regression analyses were used to identify climatic factors associated with that variability. Factor analysis identified three common growth patterns, representing groups of sites with different climate-growth relationships. At high-elevation and midrange sites in Washington and northern Oregon, growth was negatively correlated with spring snowpack depth, and positively correlated with growth-year summer temperature and the winter Pacific Decadal Oscillation index (PDO). In southern Oregon, growth was negatively correlated with spring snowpack depth and previous summer temperature, and positively correlated with previous summer precipitation. At the low-elevation sites, growth was mostly insensitive to annual climatic variability but displayed sensitivity to decadal variability in the PDO opposite to that found at high-elevation sites. Mountain hemlock growth appears to be limited by late snowmelt, short growing seasons, and cool summer temperatures throughout much of its range in the Pacific Northwest. Earlier snowmelt, higher summer temperatures, and lower summer precipitation in southern Oregon produce conditions under which growth is limited by summer temperature and/or soil water availability. Increasing atmospheric CO2 concentrations could produce warmer temperatures and reduced snowpack depths in the next century. Such changes would likely increase mountain hemlock growth

  8. Cosmogenic 10Be Exposure Age Limits on the Angel Lake Glaciation, Ruby Mountains, Northeastern Nevada

    NASA Astrophysics Data System (ADS)

    Laabs, B. J.; Munroe, J. S.; Best, L. C.; Caffee, M. W.

    2011-12-01

    Evidence of Pleistocene glaciations in the northern Great Basin of the interior western U.S. has been known for decades. Nonetheless, this area has received considerably less attention than the eastern and western extremes of the Great Basin, despite being centrally located among numerous well-dated Pleistocene glacial chronologies and in a setting where such chronologies can provide clues to the influence of North American ice sheets, Great Basin paleolakes, and atmospheric circulation changes on climate change. Among the most extensively glaciated mountains in the Great Basin are the Ruby and East Humboldt Mountains in northeastern Nevada, where the type localities for the last two Pleistocene glaciations in the region, the Lamoille and Angel Lake Glaciations, are found. The glacial record in these two ranges includes sequences of moraines deposited during the Angel Lake Glaciation, displaying abundant material suitable for terrestrial cosmogenic 10Be surface-exposure dating. Exposure ages of boulders from atop a sequence of well-preserved moraines in Seitz Canyon in the western Ruby Mountains limit the end of the Angel Lake Glaciation to 19.3 ± 1.0 ka. This preliminary age limit verifies that the Angel Lake Glaciation coincided with marine oxygen-isotope stage 2 and the global Last Glacial Maximum, and suggests that mountain glaciers in northeastern Nevada began retreating in step with the Laurentide Ice Sheet. When compared to glacial chronologies from elsewhere in the region, this age limit indicates an early start of the last deglaciation relative to the Sierra Nevada and the Wasatch Mountains, at the western and eastern extremes of the Great Basin respectively. Furthermore, this age limit suggests that ice retreat began before the highstands of the largest Great Basin paleolakes, Lakes Bonneville and Lahontan. Further development of the glacial chronology of the northern Great Basin is needed to evaluate the significance of these apparent age differences

  9. Mountain Weather and Climate, Third Edition

    NASA Astrophysics Data System (ADS)

    Hastenrath, Stefan

    2009-05-01

    For colleagues with diverse interests in the atmosphere, glaciers, radiation, landforms, water resources, vegetation, human implications, and more, Mountain Weather and Climate can be a valuable source of guidance and literature references. The book is organized into seven chapters: 1, Mountains and their climatological study; 2,Geographical controls of mountain meteorological elements; 3, Circulation systems related to orography; 4, Climatic characteristics of mountains; 5, Regional case studies; 6, Mountain bioclimatology; and 7, Changes in mountain climates. These chapters are supported by l78 diagrams and photographs, 47 tables, and some 2000 literature references. The volume has an appendix of units and energy conversion factors and a subject index, but it lacks an author index.

  10. SANTA LUCIA WILDERNESS, AND GARCIA MOUNTAIN, BLACK MOUNTAIN, LA PANZA, MACHESNA MOUNTAIN, LOS MACHOS HILLS, BIG ROCKS, AND STANLEY MOUNTAIN ROADLESS AREAS, CALIFORNIA.

    USGS Publications Warehouse

    Frizzell, Virgil A., Jr.; Kuizon, Lucia

    1984-01-01

    The Santa Lucia Wilderness Area and Garcia Mountain, Black Mountain, La Panza, Machesna Mountain, Los Machos Hills, Big Rocks, and Stanley Mountain Roadless Areas together occupy an area of about 218 sq mi in the Los Padres National Forest, California. On the basis of a mineral-resource evaluation a small area in the Black Mountain Roadless Area has a probable mineral-resource potential for uranium, and a small area in the Stanley Mountain Roadless Area has probable potential for low-grade mercury resources. Although petroleum resources occur in rocks similar to those found in the study area, no potential for petroleum resources was identified in the wilderness or any of the roadless areas. No resource potential for other mineral resources was identified in any of the areas. Detailed geologic mapping and geochemical sampling probably would increase knowledge about distribution and modes of occurrence of uranium and cinnabar in those areas, respectively.

  11. Contemporary doming of the Adirondack mountains: Further evidence from releveling

    USGS Publications Warehouse

    Isachsen, Y.W.

    1981-01-01

    The Adirondack Mountains constitute an anomalously large, domical uplift on the Appalachian foreland. The dome has a NNE-SSW axis about 190 km long, and an east-west dimension of about 140 km. It has a structural relief of at least 1600 m, and a local topographic relief of up to 1200 m. First-order leveling in 1955, and again in 1973 along a north-south line at the eastern margin of the Adirondack shows an uplift rate of 2.2 mm/yr at the latitude of the center of the dome and a subsidence rate of 2.8 mm/yr at the northern end of the line near the Canadian border. The net amount of arching along this releveled line is 9 cm ?? 2 cm (Isachsen, 1975). To test the idea that this arching represented an "edge effect" of contemporary doming of the Adirondacks as a whole, the National Geodetic Survey was encouraged to relevel a 1931 north-south line between Utica and Fort Covington (near the Canadian border) which crosses the center of the dome. The releveling showed that the mountain mass is undergoing contemporary domical uplift at a rate which reaches 3.7 mm/yr near the center of the dome (compare with 1 mm/yr for the Swiss Alps). Three other releveled lines in the area support this conclusion. ?? 1981.

  12. Geology of the central Mineral Mountains, Beaver County, Utah

    SciTech Connect

    Sibbett, B.S.; Nielson, D.L.

    1980-03-01

    The Mineral Mountains are located in Beaver and Millard Counties, southwestern Utah. The range is a horst located in the transition zone between the Basin and Range and Colorado Plateau geologic provinces. A multiple-phase Tertiary pluton forms most of the range, with Paleozoic rocks exposed on the north and south and Precambrian metamorphic rocks on the west in the Roosevelt Hot Springs KGRA (Known Geothermal Resource Area). Precambrian banded gneiss and Cambrian carbonate rocks have been intruded by foliated granodioritic to monzonitic rocks of uncertain age. The Tertiary pluton consists of six major phases of quartz monzonitic to leucocratic granitic rocks, two diorite stocks, and several more mafic units that form dikes. During uplift of the mountain block, overlying rocks and the upper part of the pluton were partially removed by denudation faulting to the west. The interplay of these low-angle faults and younger northerly trending Basin and Range faults is responsible for the structural control of the Roosevelt Hot Springs geothermal system. The structural complexity of the Roosevelt Hot Springs KGRA is unique within the range, although the same tectonic style continues throughout the range. During the Quaternary, rhyolite volcanism was active in the central part of the range and basaltic volcanism occurred in the northern portion of the map area. The heat source for the geothermal system is probably related to the Quaternary rhyolite volcanic activity.

  13. Alpine exhumation of the central Cantabrian Mountains, Northwest Spain

    NASA Astrophysics Data System (ADS)

    Fillon, C.; Pedreira, D.; Beek, P. A.; Huismans, R. S.; Barbero, L.; Pulgar, J. A.

    2016-02-01

    The Cantabrian Mountains extend along the Atlantic coast of northern Spain and are known to have experienced an Alpine phase of deformation, reactivating well-expressed Variscan structures. They form the westward continuation of the Pyrenean range and were similarly uplifted consequently to the convergence between the Iberian and European plates. Nevertheless, due to the scarcity of syntectonic sediments and structural markers in a large outcrop of Variscan basement, little is known about the precise timing and amount of the Alpine exhumation phase in the Cantabrian Mountains. We present a new low-temperature thermochronology data set, composed of nine apatite fission track (AFT) and six zircon (U-Th)/He (ZHe) ages, sampled along structurally well-constrained N-S profiles through the central part of the Cantabrian Mountains and complemented by 3-D thermokinematic modeling. The occurrence of Eocene-Oligocene AFT and ZHe ages in the center of the profiles allows us to frame the period of Alpine exhumation from 39 to 29 Ma, at a rate of 0.24-0.3 km Myr-1. Moreover, the reset ZHe ages imply significant burial of the samples, by up to 8-10 km in the center of the range. Therefore, the Alpine exhumation phase was significant, and synchronous to the main phase of exhumation in the central Pyrenees, although exhumation rates were an order of magnitude lower. Three-dimensional thermokinematic modeling of the data confirms the timing of uplift of this area, but its resolution is limited by the relatively small number of reset ages over a large area.

  14. Deep vertical propagation of mountain waves above Scandinavia

    NASA Astrophysics Data System (ADS)

    Dörnbrack, Andreas; Gisinger, Sonja; Rapp, Markus; Witschas, Benjamin; Ehard, Benedikt; Wagner, Johannes; Achtert, Peggy; Stober, Gunter; Kivi, Rigel; Gumbel, Jörg

    2015-04-01

    The project "Investigation of the life cycle of gravity waves (GW-LCYCLE) is part of the German research initiative ROMIC (Role of the Middle atmosphere In Climate) funded by the ministry of research. In close cooperation with Scandinavian partners as the Stockholm University and the Finnish Meteorological Institute a first field phase was conducted in November/December 2013. The field program combined ground-based observations of tropospheric and lower stratospheric flow and stratospheric and mesospheric temperature by lidars and radars at Alomar (N) and at Esrange (S) with airborne and balloonb