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Sample records for red river fault

  1. Late Quaternary tectonics and seismotectonics along the Red River fault zone, North Vietnam

    NASA Astrophysics Data System (ADS)

    Phan, Trong Trinh; Ngo, Van Liem; Nguyen, Van Huong; Hoang, Quang Vinh; Bui, Van Thom; Bui, Thi Thao; Mai, Thanh Tan; Nguyen, Hoang

    2012-09-01

    A study of active tectonic development in Vietnam is of great importance. Right lateral strike-slip offsets along the Red River fault during the Pliocene-present are determined by analyzing tributaries, Quaternary alluvial fans, river valley from Landsat, SPOT images, detailed topographical maps and field observation. Along the SW fault of the Red River, right lateral offsets of stream channels range between 150 and 700 m (mean offsets of 300 m). Drainage offsets (170-450 m) are found on the eastern branch. Assuming the major phase of incision is visible in this area which is close to the Red River delta due to the onset of Riss glaciation. Using the average length of offset channels and a minimum rate of 100-150 mm/yr for river propagation, we estimate the horizontal slip rates of 2.9 ± 1.7 mm/yr for Song Chay fault, 2.3 ± 1.5 mm/yr for Red River left side fault and 2.1 ± 1.5 mm/yr for Red River left side fault. Several active faults associated with it are observed in Son La area. The Phong Tho-Nam Pia fault is clearly seen in the geomorphology which separates Tu Le and Song Da rift zones. In normal fault segments striking NW-SE, SW dipping is observed clearly from SPOT images. In the field, triangular facets indicate typical dip slip displacement. Based on different data, vertical slip rate of Phong Tho-Nam Pia fault is estimated to be 0.2-0.4 mm/y for Pliocene-present, 0.5-3 mm/y for Quaternary-present and 0.6-1.7 for the present time. Based on various methods, maximum credible earthquakes for different fault segments in Vietnam were estimated.

  2. Structure and tectonic geomorphology of the Qujiang fault at the intersection of the Ailao Shan-Red River fault and the Xianshuihe-Xiaojiang fault system, China

    NASA Astrophysics Data System (ADS)

    Wang, Yang; Zhang, Bo; Hou, Jianjun; Xu, Xiwei

    2014-11-01

    The northwest-striking Qujiang fault is located at the southeastern tip of the Sichuan-Yunnan block, which is bounded by the Ailao Shan-Red River fault and the Xianshuihe-Xiaojiang fault system. The Qujiang fault is one of the most seismically active faults in western Yunnan, China and is considered to be the seismogenic fault of the 1970 Ms 7.7 Tonghai earthquake. In this study, we examine the geometry, kinematics, and geomorphology of this fault through field observations, satellite images, and DEMs. It is a Holocene active fault characterized by dextral strike-slip movements with dip-slip components. It can be divided into northwest and southeast segments depending on different kinematics. The northwest segment from Baiyizhai to Wujie shows right-lateral strike slip with normal components, whereas it is characterized by dextral movements with the northeast wall thrusting over the opposite in the southeast segment from Wujie to Miaobeishan. The geophysical data combined with our investigations indicate that the fault dips steeply to the NE at depth, while secondary faults with different dip directions developed at shallow surface owing to fault bifurcation. During the Tonghai earthquake, a blind fault may have developed on the southwest wall, resulting in aftershocks concentrated to the southwest of the surface raptures. Multiple tectonic landforms are developed along the fault. The right-lateral Holocene slip rate was determined to be 2.84-3.27 mm/year based on radiometrically dated offset gullies. Our analyses show that the present deformation at the intersection of the Ailao Shan-Red River fault and the Xianshuihe-Xiaojiang fault system is partitioned into a shortening distributed over a region ~ 150 km wide and a right-lateral strike slip localized on the Qujiang and Jianshui faults. Since the late Pleistocene, the Qujiang fault has been playing an important role in accommodating the ongoing SE-directed movements of the Sichuan-Yunnan block, creating strong earthquakes to release strain energy.

  3. Potassic magma genesis and the Ailao Shan-Red River fault

    NASA Astrophysics Data System (ADS)

    Flower, Martin F. J.; Hong, Nguy?n; Lo, Chinh-hua; Ch, Cung Thu'?'ng; Cu''ng, Nguy?n Qu?c; Liu, Fu-tian; Deng, Jin-fu; Mo, Xuan-xue

    2013-09-01

    Two types of K-rich magma of Eocene to Early Oligocene (ca. 40-30) and Plio-Pleistocene (ca. 5-0.1 Ma) age were emplaced prior to and following left-lateral slip on the Ailao Shan-Red River (ASRR) fault, a regional shear zone extending between southwest China and the Tonkin Gulf (South China Sea) that accommodated 'escape' of the Indochina block. The first type is exposed in the Dali-Lijiang and adjacent regions of western Yunnan and Sichuan and comprises ultramafic potassic to ultrapotassic 'absarokites' and their shoshonite, banakite, and SiO2-rich derivatives which were emplaced immediately prior to activation of the ASRR fault. They are characterized by high Mg.-nos, and low contents of fusible oxides (FeO*, CaO, Al2O3), for equivalent MgO content, and pronounced primitive mantle-normalized high-field strength element (HFSE) depletions. In contrast, 'post-escape' K-rich magmas were erupted in the Puer, Maguan-Pingbian regions of south and southeast Yunnan. Apart from their relative enrichments in potassium they show typical HFSE-rich intra-plate compositional affinity. Geological and geomorphic evidence, and thermochronologic age dating of metamorphisc events, suggest that left-lateral shearing occurred between ca. 30 and 17 Ma; thereby accommodating the southeastward 'escape' of Indochina and (possibly) two episodes of spreading in the South China Sea. The southwestern part of Dali-Lijiang magmatic products was detached and offset by ca. 600 km and are now located in Phan Xi Pang in northern Viet Nam. The same is true for the Permo-Triassic Emeishan flood basalts, whose western exposures were likewise displaced by the same amount and are now represented by the Song Da complex, also in northern Viet Nam. Here, we report geochemical, isotopic, and 40Ar/39Ar age data for samples from both the 'pre-escape' Dali-Lijiang magmas and the 'post-escape' K-rich Puer, Maguan-Pingbian basalts and basanites, with a view to comparing and contrasting their interpolated source compositions, estimated conditions of upper mantle melt segregation and, by inference, their mantle dynamic and contamination histories insofar as these were conditioned by the India-Asia collision. Our interpretations yielded two complementary conclusions. The first contends that the pre-escape magmas result from adiabatic melting of crust-contaminated asthenosphere comprising a 'mlange' of continental lithospheric mantle (CLM) (hydrated by sab-derived hysdrous fluids released at 0.2-0.5 GPa) and lower crust, delaminated from the overriding plate during mantle wedge corner flow and further enriched by metasomatic melts of subducted continental crust. We postulate that incipient H2O-saturated melting of the 'mlange' occurs at depths of between ca. 100 and 200 km after being 'dragged' down by relict oceanic slab fragments, in response to the dehydration of supra-subduction amphibole- and phlogopite. The ensuing viscosity 'crisis' and buoyancy relative to ambient 'fertile' convecting mantle of such asthenospheric 'pockets', and the collision-related change from lithospheric compression to extension, almost certainly predisposes such a refractory yet crust-contaminated 'pockets' to rapid adiabatic melting. The second conclusion concerns the post-escape K-rich basalts and basanites and is based on the contention that decompression melting of thermally anomalous K-rich asthenospheric occurred in response to regional post-escape transtension, concomitant with the cessation Indochina escape and contiguous seafloor spreading. However, although these magmas share the HFSE-rich fertile source character of other, widely dispersed, post-escape Cenozoic basalts they more specifically resemble relatively rare examples of intra-plate, K-rich activity observed in northeast China, central Spain, and elsewhere in Asia and Europe, arguably (indirectly) reflecting mantle perturbations caused by major continental collisions.

  4. Reactivation of a collisional suture by Miocene transpressional domes associated with the Red River and Song Chay detachment faults, northern Vietnam

    NASA Astrophysics Data System (ADS)

    Osozawa, Soichi; Van Vuong, Nguyen; Van Tich, Vu; Wakabayashi, John

    2015-06-01

    Elongate Miocene gneissose and granitic domes in northern Vietnam formed in a dextral-transpressional ductile shear regime, possibly associated with large-scale restraining step-overs along dextral faults. Initial anticlinal D1 doming involved folding of both basement and hanging wall rocks with D1 secondary folds that verge toward the anticlinal axes. Such folds reflect dome-scale flexural slip folding. With continued shortening, D2 detachment faults developed on the flanks of the anticlines along the hanging wall-basement interface, so that the basement was extruded vertically into the overlying hanging wall rocks. The detachment faults were associated with D2 drag folds that verge away from the anticlinal axes. The hanging wall assemblage lacks a well-ordered stratigraphy, displaying primarily block-in-matrix fabric. We identified bedded cherts, associated with umbers and alkalic basaltic intrusions within these hanging wall rocks, a first report of such rocks from Vietnam. The association of cherts, umbers, and basaltic intrusions and extrusions with block-in-matrix units with clastic rocks strongly suggest that the hanging wall rocks comprise part of a subduction complex. Because the base of a subduction complex is a former subduction megathrust horizon, the hanging wall-basement interface represents a reactivated collisional suture. Such a suture was probably associated with the Indosinian orogeny, and the basement should be the Indochina continental block. This structure may have influenced the position of Miocene dextral faulting in addition to controlling the position of the dome detachments. The well-known Red River fault marks the boundary of one of the domes, but in this region it appears to be a detachment (normal) fault rather than a dextral strike-slip fault. However, the association with the dome evolution with large-scale restraining step-overs suggests that dextral faulting associated with dome development may lie further away from the dome axes than the detachment.

  5. Late Neogene structural inversion around the northern Gulf of Tonkin, Vietnam: Effects from right-lateral displacement across the Red River fault zone

    NASA Astrophysics Data System (ADS)

    Fyhn, Michael B. W.; Phach, Phung V.

    2015-02-01

    Continental extrusion may take up much of the deformation involved in continental collisions. Major strike-slip zones accommodate the relative extrusion displacement and transfer deformation away from the collision front. The Red River fault zone (RRFZ) accommodated left- and right-lateral displacements when Indochina and South China were extruded during the Indian-Eurasian collision. The northern Song Hong basin onshore and offshore in the Gulf of Tonkin delineates the direct extension of the RRFZ and thus records detailed information on the collision-induced continental extrusion. We assess the rapidly evolving kinematics of the fault zone buried within the basin based on seismic analysis. Contrary to previous studies, we do not identify indications for latest Miocene left-lateral motion across the RRFZ. We tentatively consider the shift from left- to right-lateral motion to have occurred already during the middle Late Miocene as indicated by inversion of NE-SW-striking faults in the Bach Long Vi area. Right-lateral displacement terminated around the end of the Miocene in the Song Hong basin. However, continued inversion in the Bach Long Vi area and NNW-SSE-striking normal faulting suggests a stress regime compatible with right-lateral motion across the onshore part of the RRFZ continuing to the present. Inversion around the Bach Long Vi Island may have accommodated up to a few kilometers of right-lateral displacement between the Indochina and South China blocks. Comparable NE-SW-striking fault zones onshore may have accommodated a larger fraction of the right-lateral slip across the RRFZ, thus accounting for the restricted transfer of lateral displacement to the offshore basins.

  6. 33 CFR 165.T09-0263 - Safety zone; Red River Safety Zone, Red River, MN.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Safety zone; Red River Safety Zone, Red River, MN. 165.T09-0263 Section 165.T09-0263 Navigation and Navigable Waters COAST GUARD... § 165.T09-0263 Safety zone; Red River Safety Zone, Red River, MN. (a) Location. The following area is...

  7. USGS Research on the Flooded Red River

    The 2011 Red River flood was the third largest in Fargo, ND since 1900. In the background of this photo, USGS authorized personnel take a boat out on the river to record streamflow and water level measurements....

  8. 33 CFR 117.491 - Red River.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Red River. 117.491 Section 117.491 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Louisiana § 117.491 Red River. (a) The draw of the Union...

  9. 33 CFR 117.491 - Red River.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Red River. 117.491 Section 117.491 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Louisiana § 117.491 Red River. (a) The draw of the Union...

  10. 33 CFR 117.135 - Red River.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Red River. 117.135 Section 117.135 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Arkansas § 117.135 Red River. The draws of the bridges...

  11. 33 CFR 117.135 - Red River.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Red River. 117.135 Section 117.135 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Arkansas § 117.135 Red River. The draws of the bridges...

  12. 33 CFR 117.135 - Red River.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Red River. 117.135 Section 117.135 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Arkansas § 117.135 Red River. The draws of the bridges...

  13. 33 CFR 117.491 - Red River.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Red River. 117.491 Section 117.491 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Louisiana § 117.491 Red River. (a) The draw of the Union...

  14. 33 CFR 117.491 - Red River.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Red River. 117.491 Section 117.491 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Louisiana § 117.491 Red River. (a) The draw of the Union...

  15. 33 CFR 117.491 - Red River.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Red River. 117.491 Section 117.491 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Louisiana § 117.491 Red River. (a) The draw of the Union...

  16. 33 CFR 117.135 - Red River.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Red River. 117.135 Section 117.135 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Arkansas § 117.135 Red River. The draws of the bridges...

  17. 33 CFR 117.135 - Red River.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Red River. 117.135 Section 117.135 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Arkansas § 117.135 Red River. The draws of the bridges...

  18. RED RIVER BASIN BIOLOGICAL MONITORING WORKGROUP

    EPA Science Inventory

    The goal of this project is to improve coordination of biological monitoring efforts in the Red River Basin. This is to be accomplished through coordination of a study to develop sampling protocols for macroinvertebrates in the main stream and lower tributaries of the Red River....

  19. Hairpin river loops and slip-sense inversion on southeast Asian strike-slip faults

    NASA Astrophysics Data System (ADS)

    Lacassin, Robin; Replumaz, Anne; Hervé Leloup, P.

    1998-08-01

    In the Golden Triangle region of southeast Asia (northern Thailand, Laos and Burma, southern Yunnan), the Mekong, Salween, and neighboring rivers show hairpin geometries where they cross active strike-slip faults. Restoration of young, left-lateral offsets of these rivers leaves residual right-lateral bends of many kilometers. We interpret these hairpins as evidence of late Cenozoic slip-sense inversion on these faults, about 5 to 20 Ma. Near the Red River fault, stress field and slip-sense inversion occurred ca. 5 Ma. This implies that the present course of these large rivers has existed for at least several million years. Pliocene Quaternary slip rates, possibly on the order of 1 mm/yr, are inferred on each of the strike-slip faults of the Golden Triangle.

  20. 76 FR 23485 - Safety Zone; Red River

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-27

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Red River AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a temporary safety zone for all waters of the... across latitude 46 20'00'' N, extending the entire width of the river. This safety zone is needed...

  1. Comparison of Cenozoic Faulting at the Savannah River Site to Fault Characteristics of the Atlantic Coast Fault Province: Implications for Fault Capability

    SciTech Connect

    Cumbest, R.J.

    2000-11-14

    This study compares the faulting observed on the Savannah River Site and vicinity with the faults of the Atlantic Coastal Fault Province and concludes that both sets of faults exhibit the same general characteristics and are closely associated. Based on the strength of this association it is concluded that the faults observed on the Savannah River Site and vicinity are in fact part of the Atlantic Coastal Fault Province. Inclusion in this group means that the historical precedent established by decades of previous studies on the seismic hazard potential for the Atlantic Coastal Fault Province is relevant to faulting at the Savannah River Site. That is, since these faults are genetically related the conclusion of ''not capable'' reached in past evaluations applies.In addition, this study establishes a set of criteria by which individual faults may be evaluated in order to assess their inclusion in the Atlantic Coast Fault Province and the related association of the ''not capable'' conclusion.

  2. 33 CFR 207.380 - Red Lake River, Minn.; logging regulations for portion of river above Thief River Falls.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false Red Lake River, Minn.; logging... Red Lake River, Minn.; logging regulations for portion of river above Thief River Falls. (a) Parties wishing to run logs on Red Lake River must provide storage booms near the head of the river to take...

  3. 33 CFR 207.380 - Red Lake River, Minn.; logging regulations for portion of river above Thief River Falls.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Red Lake River, Minn.; logging... Red Lake River, Minn.; logging regulations for portion of river above Thief River Falls. (a) Parties wishing to run logs on Red Lake River must provide storage booms near the head of the river to take...

  4. 33 CFR 207.380 - Red Lake River, Minn.; logging regulations for portion of river above Thief River Falls.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Red Lake River, Minn.; logging... Red Lake River, Minn.; logging regulations for portion of river above Thief River Falls. (a) Parties wishing to run logs on Red Lake River must provide storage booms near the head of the river to take...

  5. 33 CFR 207.380 - Red Lake River, Minn.; logging regulations for portion of river above Thief River Falls.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Red Lake River, Minn.; logging... Red Lake River, Minn.; logging regulations for portion of river above Thief River Falls. (a) Parties wishing to run logs on Red Lake River must provide storage booms near the head of the river to take...

  6. 33 CFR 207.380 - Red Lake River, Minn.; logging regulations for portion of river above Thief River Falls.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 3 2013-07-01 2013-07-01 false Red Lake River, Minn.; logging... Red Lake River, Minn.; logging regulations for portion of river above Thief River Falls. (a) Parties wishing to run logs on Red Lake River must provide storage booms near the head of the river to take...

  7. Saline Soils in the Red River Valley

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Red River Valley of the North stretches over 315 miles from northeastern South Dakota through northwestern Minnesota and eastern North Dakota into southern Manitoba. Nearly all this area is in dryland farms and is highly productive. Salinity has been recognized as a major factor affecting crop p...

  8. Cubic Foot - Red River at Fargo

    A white box in the foreground of this photograph demonstrates one cubic foot. The peak streamflow at the USGS Red River of the North at Fargo, ND streamgage was around 26,000 cubic feet per second on April 9, 2011....

  9. USGS Research on the Red River in Fargo

    USGS scientists Joel Galloway and Dan Thomas prepare to take streamflow and water level measurements of the flooded Red River in downtown Fargo, ND. The USGS Red River of the North at Fargo streamgage can be seen in the background....

  10. The Red River Valley archeological project

    NASA Technical Reports Server (NTRS)

    Bennett, Jack; Smith, Lawson; Laustrup, Mark

    1986-01-01

    The Red River Valley Archeology Project is a long-term effort involving numerous individuals and institutions engaged in archeological investigations in the Texas and Oklahoma portions of the Red River Valley. To date the focus of the project was on site location. The project acquired both Thermal Infrared Multispectral Scanner (TIMS), TMS, and color infrared photographs over a significant portion of the project area in an effort to define signatures for archeological sites and to assist in the detailed geomorphological mapping of the flood plain. Preliminary analysis of acquired data indicates that both the TIMS and TMS can make a substantial contribution to landform definition, the identification of cultural resources, and to the clarification of site-landform correlations in this riverine environment.

  11. Water resources of Red River Parish, Louisiana

    USGS Publications Warehouse

    Newcome, Roy; Page, Leland Vernon

    1963-01-01

    Red River Parish is on the eastern flank of the Sabine uplift in northwestern Louisiana. The 'area is underlain by lignitic clay and sand of Paleocene and Eocene age which dip to the east at the rate of about 30 feet per mile. The Red River is entrenched in these rocks in the western part of the parish. Alternating valley filling and erosion during the Quaternary period have resulted in the present lowland with flanking terraces. In the flood-plain area moderate to large quantities of very hard, iron-bearing water, suitable for irrigation, are available to wells in the alluvial sand and gravel of Quaternary age. The aquifer ranges in thickness from 20 to slightly more than 100 feet. It is recharged by downward seepage of rainfall through overlying clay and silt, by inflow from older sands adjacent to and beneath the entrenched valley, and by infiltration from the streams where the water table is below stream level during flood stages or as a result of pumping. Water levels are highest in the middle of the valley. Ground water moves mainly toward the Red River on the east and Bayou Pierre on the west, but small amounts move down the valley. Computations based on water-level and aquifer-test data indicate that the Quaternary alluvium contains more than 330 billion gallons of ground water in storage and that the maximum discharge of ground water to the streams is slightly more than 30 mgd (million gallons per day). At times of high river stage, surface water flows into the aquifer at a rate that depends in part upon the height and duration of the river stage. Moderate supplies of soft, iron-bearing water may be obtained from dissected Pleistocene terrace deposits that flank the flood plains of the Red River and Black Lake Bayou. However, the quantity of water that can be pumped from these deposits varies widely from place to place because of differences in the areal extent and saturated thickness of the segments of the deposits; this extent and thickness are governed in turn by the amount of erosion the deposits have undergone. Beds of fine-grained lignitic sands of Tertiary age contain water of generally good quality to depths of 150 to 450 feet. The thinness and low permeability of the sands restrict their development to low-yield wells. Water from these sands in the western part of the parish, where they lie beneath the alluvial valley, is more mineralized than that from the younger Tertiary sands exposed in the east-central area. Streamflow records have been collected on the principal streams in Red River Parish since 1939. Additional spot low-flow data were obtained on several small streams originating within the parish for a study made in connection with the preparation of this report. Quality-of-water data for streams in the parish were collected on an occasional spot-sampling basis prior to and during this investigation. The largest source of surface water in the parish is the Red River, which drains approximately 63,400 square miles upstream from the parish. The Red River has an average flow of about 13,100 cfs (cubic feet per second), or about 8,500 mgd. Many of the streams that drain the upland area are not dependable sources of supply because their flows are not well sustained during dry seasons. The average annual precipitation over the parish is about 52 inches, of which about 17 inches becomes runoff; this runoff is equivalent to a continuous flow of about 1.25 cfs per square mile. Seasonal and annual runoff varies, but no significant trends have been noticed. The principal surface-water problems in the parish pertain to flood control, drainage, irrigation, and navigation. Flood problems have been alleviated considerably by the operation of Denison Dam (Lake Texoma), the completion of levees on the Red River, channel improvements on Bayou Pierre, and the completion of Wallace Lake reservoir on Cypress Bayou. There are wet lands along the Red River that would be very productive if properly drained

  12. Numerical modelling of river rearrangement along strike-slip faults

    NASA Astrophysics Data System (ADS)

    Brocard, G. Y.; Simon-Labric, T.; van der Beek, P.; Teyssier, C.

    2009-12-01

    Most studies of climate-tectonic interactions have focused on steady state orogens that evolve through orogen-normal convergence. Yet, most orogens have a major component of strike skip (wrenching). Although river captures occur in various kinds of geomorphic settings, they are frequently produced in such orogens by strike-slip faulting. The impacts of river captures are not well quantified because compelling diagnostic features and good quality proximal records are rarely found. We have modified the CASCADE numerical surface-process model to incorporate horizontal motion across a strike-slip fault and to study the evolution of drainage organization. Two river geometries are used to study the effect of horizontal movement on drainage systems. (1) The first simulates the deformation of an isolated crosswise stream. The continued horizontal displacement of streams leads to stream deflection and formation of a deep valley along the fault. The elongation of the river is not limited by the presence of other streams, and the lengthening process lowers river gradients and likely diminishes the river’s erosional efficiency. The ratio between uplift and strike-slip rates controls the response of drainage systems. We define two extreme cases (i) with a low ratio, the river presents a flat profile along the fault and a knick-point at a gorge outlet where the river leaves the fault; further work is in progress to test the influence of different parameters on the position of the knick-point; (ii) with a high ratio, catchment uplift compensates the horizontal elongation of the river. The river keeps the same profile. The system remains in steady-state. (2) The second geometry simulates two parallel crosswise rivers. In this case, lenghtening ends when drains are brought into contact by strike-slip faults. The physical barrier between them is tectonically removed. Our models show an expected transient increase in local relief and therefore basin incision. Through elongation and capture, deformation in a wrench zone produces a constantly evolving pattern of stream reaches with various incision rates. Drainage basins located upstream from the wrench zone experience a series of sudden captures and longer intervening periods of lengthening and slowing erosion. This results in oscillations in incision rate and internal drainage adjustments. Erosion and landscape, in these wrenched systems, thus operate in permanent disequilibrium.

  13. 33 CFR 117.665 - Red River of the North.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Red River of the North. 117.665 Section 117.665 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Minnesota § 117.665 Red River of the North. The...

  14. 33 CFR 117.129 - Little Red River.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Little Red River. 117.129 Section 117.129 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Arkansas § 117.129 Little Red River. The draws of...

  15. 33 CFR 117.665 - Red River of the North.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Red River of the North. 117.665 Section 117.665 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Minnesota § 117.665 Red River of the North. The...

  16. 33 CFR 117.129 - Little Red River.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Little Red River. 117.129 Section 117.129 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Arkansas § 117.129 Little Red River. The draws of...

  17. 33 CFR 117.129 - Little Red River.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Little Red River. 117.129 Section 117.129 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Arkansas § 117.129 Little Red River. The draws of...

  18. 33 CFR 117.665 - Red River of the North.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Red River of the North. 117.665 Section 117.665 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Minnesota § 117.665 Red River of the North. The...

  19. 33 CFR 117.129 - Little Red River.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Little Red River. 117.129 Section 117.129 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Arkansas § 117.129 Little Red River. The draws of...

  20. 33 CFR 117.129 - Little Red River.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Little Red River. 117.129 Section 117.129 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Arkansas § 117.129 Little Red River. The draws of...

  1. 33 CFR 117.665 - Red River of the North.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Red River of the North. 117.665 Section 117.665 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Minnesota § 117.665 Red River of the North. The...

  2. 33 CFR 117.665 - Red River of the North.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Red River of the North. 117.665 Section 117.665 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Minnesota § 117.665 Red River of the North. The...

  3. Asymmetrical valleys created by the geomorphic response of rivers to strike-slip fault

    NASA Astrophysics Data System (ADS)

    Zhang, Ke; Liu, Kaiyu; Yang, Jinchun

    2004-11-01

    Offset fluvial valleys, including rivers beheaded and deflected by strike-slip faults, have long been used to estimate horizontal displacements on the faults. Larger rivers crossing such faults, however, sometimes show either no offset or only a small amount of offset compared to smaller rivers crossing the same faults. The larger rivers with higher erosional rates may widen their valleys asymmetrically downstream of strike-slip faults, rather than being beheaded or deflected. Examples are described from the Yellow River near the NE margin of the Tibetan Plateau. River beheading and asymmetrical widening are two end-members of a fluvial valley's response to strike-slip faulting, whereas deflection is a combination of both. Recognition of the formation of such asymmetrical valleys related to strike-slip faulting will help to understand fault activity better over longer time spans and enable a re-evaluation of many fault histories worldwide.

  4. Long-term changes to river regimes prior to late Holocene coseismic faulting, Canterbury, New Zealand

    NASA Astrophysics Data System (ADS)

    Campbell, Jocelyn K.; Nicol, Andrew; Howard, Matthew E.

    2003-09-01

    Two sites are described from range front faults along the foothills of the Southern Alps of New Zealand, where apparently a period of 200-300 years of accelerated river incision preceded late Holocene coseismic ruptures, each probably in excess of M w 7.5. They relate to separate fault segments and seismic events on a transpressive system associated with fault-driven folding, but both show similar evidence of off-plane aseismic deformation during the downcutting phase. The incision history is documented by the ages, relative elevations and profiles of degradation terraces. The surface dating is largely based on the weathering rind technique of McSaveney (McSaveney, M.J., 1992. A Manual for Weathering-rind Dating of Grey Sandstones of the Torlesse Supergroup, New Zealand. 92/4, Institute of Geological and Nuclear Sciences), supported by some consistent radiocarbon ages. On the Porters Pass Fault, drainage from Red Lakes has incised up to 12 m into late Pleistocene recessional outwash, but the oldest degradation terrace surface T I is dated at only 690±50 years BP. The upper terraces T I and T II converge uniformly downstream right across the fault trace, but by T III the terrace has a reversed gradient upstream. T II and T III break into multiple small terraces on the hanging wall only, close to the fault trace. Continued backtilting during incision caused T IV to diverge downstream relative to the older surfaces. Coseismic faulting displaced T V and all the older terraces by a metre high reverse scarp and an uncertain right lateral component. This event cannot be younger than a nearby ca. 500 year old rock avalanche covering the trace. The second site in the middle reaches of the Waipara River valley involves the interaction of four faults associated with the Doctors Anticline. The main river and tributaries have incised steeply into a 2000 year old mid-Holocene, broad, degradation surface downcutting as much as 55 m. Beginning approximately 600 years ago accelerating incision eventually attained rates in excess of 100 mm/year in those reaches closely associated with the Doctors Anticline and related thrust and transfer faults. All four faults ruptured, either synchronously or sequentially, between 250 and 400 years ago when the river was close to 8 m above its present bed. Better cross-method checks on dating would eliminate some uncertainties, but the apparent similarities suggest a pattern of precursor events initiated by a period of base level drop extending for several kilometres across the structure, presumably in response to general uplift. Over time, deformation is concentrated close to the fault zone causing tilting of degradation terraces, and demonstrably in the Waipara case at least, coseismic rupture is preceded by marked acceleration of the downcutting rate. Overall base level drop is an order of magnitude greater than the throw on the eventual fault scarp. The Ostler Fault (Van Dissen et al., 1993) demonstrates that current deformation is taking place on similar thrust-fault driven folding in the Southern Alps. Regular re-levelling since 1966 has shown uplift rates of 1.0-1.5 mm/year at the crest of a 1-2 km half wave length anticline, but this case also illustrates the general problem of interpreting the significance of rates derived from geophysical monitoring relative to the long term seismic cycle. If the geomorphic signals described can be shown to hold for other examples, then criteria for targeting faults approaching the end of the seismic cycle in some tectonic settings may be possible.

  5. Paleoseismology of the Denali fault at the Nenana River

    NASA Astrophysics Data System (ADS)

    Taylor, T. P.; Bemis, S. P.

    2012-12-01

    The Denali fault is a major right-lateral strike-slip fault that has seen increased investigation since the 2002 M 7.9 rupture. The western limit of the 2002 rupture lies 60 km east of the Parks Highway and the remainder of the Denali fault west of this point has not experienced a historic rupture. The Denali fault trace at the Parks Highway has seen only reconnaissance investigation and paleoseismic data remains nonexistent. If the Denali fault slip rate at the Parks Highway is similar to the slip rates determined to the east (~10mm/yr.) and west (~7-9mm/yr.), then at least one meter of strain has accumulated since the last major earthquake on this portion of the fault. To contribute to the development of the paleoearthquake history of the Denali fault west of the 2002 rupture, we chose to target the portion of the fault adjacent to the Parks Highway where it crosses the Nenana River. Using LiDAR digital elevation models we identified a portion of the Denali Fault immediately east of the Parks Highway to investigate. The site, Dead Mouse, is located on a fluvial terrace approximately 10 m above the modern Nenana River, and the scarp is characterized by 3 en-echelon fissures that trend 30 degrees clockwise relative to the main fault trace. We excavated two trenches, DM1 and DM2, exposing evidence for 3, possibly 4, earthquakes. Our first trench, DM1, crosses the well-defined surface trace of the Denali fault, whereas the second trench, DM2, is approximately 5 m northeast of DM1 and across an en-echelon fissure. DM1 exposed up to 1.7 m of fine grained sediment lying on top of fluvial gravels; hand-augering revealed up to 1 m of additional fine grained sediment below our exposed stratigraphy. DM1 also exposed evidence of multiple deformation events, with the most recent event creating two fissure-like rubble zones with normal displacement. DM2 exposed up to 1.5 m of fine grained sediment also lying on top of fluvial gravels; further augering revealed up to 2 m of additional fine grained sediment below our exposed stratigraphy. DM2 exposed a series of north-dipping reverse faults and south-dipping normal faults suggesting multiple deformational events. Fault displacements in both DM1 and DM2 trenches are well-constrained by organic-bearing horizons and dating of radiocarbon samples from these horizons are in progress. The thickness of fine-grained sediment and abundant dateable material illustrate the significant potential for this site to expand the paleoseismic record of the Denali fault. Furthermore, our interpretation of the emplacement of these fine-grained sediments suggests significant flood events during the recent history of the Nenana River.

  6. Numerical modelling of river reorganization along strike-slip faults

    NASA Astrophysics Data System (ADS)

    Simon-Labric, T.; van der Beek, P.; Teyssier, C.; Brocard, G.

    2009-04-01

    Most studies of climate-tectonic interactions have focused on steady state orogens that evolve through orogen-normal convergence. Yet, most orogens have a major component of strike skip (wrenching). Although river captures occur in various kinds of geomorphic settings, they are frequently produced in such orogens by strike-slip faulting. The impacts of river captures are not well quantified because compelling diagnostic features and good quality proximal records are rarely found. CASCADE numerical simulation code (Braun and Sanbridge, 1997) has been modified to model horizontal motion across a strike-slip fault and to witness the evolution of river drainage organization. Two river geometries are used to study the effect of horizontal movement on river drainage system. (1) The first one simulates the deformation of an "isolated crosswise stream". The continued horizontal displacement of streams leads to stream deflection and formation of a deep valley along the fault. The elongation of the river is not limited by the presence of other streams, and the lengthening process lowers river gradients and likely diminishes the river's erosional efficiency. (2) The second geometry simulates two parallel crosswise rivers. In this case, lenghtening ends when drains are brought into contact by strike-slip faults. The physical barrier between them is tectonically removed. Further work is in progress to test the influence of capture on the basin incision. First results seem to show an expected transient increase in local relief and therefore basin incision. Through elongation and capture, deformation in a wrench zone produces a constantly evolving pattern of stream reaches with various incision rates. Drainage basins located upstream from the wrench zone experience a series of sudden captures and longer intervening periods of lengthening and slowing erosion. This results in oscillations in incision rate and internal drainage adjustments. Erosion and landscape, in these wrenched systems, thus operate in permanent disequilibrium. Braun, J. and Sambridge, M., 1997, Modelling landscape evolution on geologic time scales: a new method based on irregular spatial discretization, Basin Research, v.9, pp.27-52.

  7. The Bear River Fault Zone, Wyoming and Utah: Complex Ruptures on a Young Normal Fault

    NASA Astrophysics Data System (ADS)

    Schwartz, D. P.; Hecker, S.; Haproff, P.; Beukelman, G.; Erickson, B.

    2012-12-01

    The Bear River fault zone (BRFZ), a set of normal fault scarps located in the Rocky Mountains at the eastern margin of Basin and Range extension, is a rare example of a nascent surface-rupturing fault. Paleoseismic investigations (West, 1994; this study) indicate that the entire neotectonic history of the BRFZ may consist of two large surface-faulting events in the late Holocene. We have estimated a maximum per-event vertical displacement of 6-6.5 m at the south end of the fault where it abuts the north flank of the east-west-trending Uinta Mountains. However, large hanging-wall depressions resulting from back rotation, which front scarps that locally exceed 15 m in height, are prevalent along the main trace, obscuring the net displacement and its along-strike distribution. The modest length (~35 km) of the BRFZ indicates ruptures with a large displacement-to-length ratio, which implies earthquakes with a high static stress drop. The BRFZ is one of several immature (low cumulative displacement) normal faults in the Rocky Mountain region that appear to produce high-stress drop earthquakes. West (1992) interpreted the BRFZ as an extensionally reactivated ramp of the late Cretaceous-early Tertiary Hogsback thrust. LiDAR data on the southern section of the fault and Google Earth imagery show that these young ruptures are more extensive than currently mapped, with newly identified large (>10m) antithetic scarps and footwall graben. The scarps of the BRFZ extend across a 2.5-5.0 km-wide zone, making this the widest and most complex Holocene surface rupture in the Intermountain West. The broad distribution of Late Holocene scarps is consistent with reactivation of shallow bedrock structures but the overall geometry of the BRFZ at depth and its extent into the seismogenic zone are uncertain.

  8. The Study of Crustal Heterogeneity in Ma River Fault Zone, Vietnam : An Application in Receiver Function

    NASA Astrophysics Data System (ADS)

    Su, C. M. M.; Wen, S.; Tang, C. C.; Yeh, Y. L.; Toan, D. V.; Phong, L. H.; Chen, C.

    2014-12-01

    The Indochina block is located at the junction of four plates, which are India, Eurasia, Philippine Sea and Pacific plates, and the geological evolution at this area is also complex. Due to the well-known Red River fault zone play an important role in the evolution of the escape of the Indochina block, the southern part of this fault zone also exist another boundary fault zone, which is called Ma river fault. This area still exists many unknowns in the tectonic evolution. Therefore, this study analyzes teleseismic receiver functions to determine the crustal structure along the Ma river fault, northern Vietnam. We have selected teleseismic events with Mw≥5, and epicenter distance is between 30° and 90° and a Multiple-Taper Correlation (MTC) method is adapted to calculate receiver functions (RFs) for each station. The converted phase, such as P-to-S obtained from RFs, allows us to have insights on the characteristics of crustal structures including the dip of discontinuous interface and anisotropy as well. The above properties have significant effects on amplitudes and arrival time of RFs. Thus, we use Neighborhood Algorithm applied to receiver functions computed from 5 stations has yielded optimum crustal models that include anisotropy and has minimum misfit between the observed RFs and synthetic ones. Our preliminary results indicate that the depth of the Moho discontinuity in the Ma river fault zone is between 25 km and 35 km, the range of S-wave velocity is from 3.6 km/s to 4.5 km/s, and the orientations of crustal anisotropy are related with the local stress status as well. In addition, the low-velocity zone in the lower crust is observed beneath our study area. We hypothesize that the low-velocity zone in the lower crust might be caused by rising of upper mantle, or an extension of the low-velocity zone in the lower crust which is observed beneath the southeastern Tibet and the South China block.

  9. Fault patterns in Benin River and Makaraba Fields: A regional play type for the Niger Delta

    SciTech Connect

    Adeyekun, A.B.; Faparusi, B.D.; Nunns, A.G.

    1995-08-01

    Using 830 km{sup 2} of excellent 3-D seismic data, we determined the fault patterns that are responsible for hydrocarbon entrapment in the Benin River and Makaraba fields, onshore northwestern Niger Delta. Both fields are trapped downthrown to the major listric GbokoMaka growth fault system, which trends E18{degrees}S for over 40 km, and has at least 2000 m of displacement to the southwest. Several major splay faults break off the main trend in a southeasterly direction, creating a series of fault-bounded structural compartments. Each of these compartments opens to the southeast and has a structural attic at the junction of the splay fault with the main fault trend. These compartments create large-scale traps for hydrocarbons migrating from east to west up the gentle regional dip within the Miocene Ughelli depobelt. The Benin River field is trapped in the major compartment between the GbokoMaka fault and the Benin River splay fault. The large Makaraba field is similarly trapped between the GbokoMaka and MakaWest faults. Such traps require an upthrown fault seal at the master fault and a downthrown fault seal at the splay fault. In the Makamba field, the trap potential is enhanced by rollover into the GbokoMaka fault. The same structural style is also evident along several other major fault trends to the north and the south, and probably represents an important play type in the onshore western Niger delta.

  10. Distribution of faults in a transition zone: Bimodal faulting in the Pit River region, Shasta County, California

    NASA Astrophysics Data System (ADS)

    Austin, L. J.; Weldon, R. J.; Paulson, K. T.

    2012-12-01

    Northern California marks a zone of transition between oblique subduction in Cascadia, dextral transtension in Walker Lane, and north-south compression of the Klamath Mountains. Because of its unique location, the region between Mt. Shasta and Lassen Peak provides insight into the distribution of deformation in regions of transitional tectonic regimes. In particular, the Pit River region provides several excellent exposures of faults in a diatomite quarry and in larger regional structures. We present information on the distribution, amount of slip, and orientation of local faults, and demonstrate how these data reflect the interaction of multiple regional stress fields. We have measured and compiled the orientations of many small faults to evaluate the distribution of deformation in a complex zone of oblique extension and compression. A ~0.5 km2 diatomite quarry near the Pit River and Lake Britton exposes hundreds of faults with small amounts of displacement. Two main faulting patterns emerge: 1) high angle NW/SE-striking faults characterized by normal, oblique normal, or strike slip kinematic indicators; and 2) lower angle E/W-striking faults with evidence of reverse to oblique reverse motion. We find that the regional landscape reflects a dominant mode of faulting that is NW/SE-striking normal, oblique normal, or strike slip; the Hat Creek and Rocky Ledge faults, each with tens of meters of oblique normal offset, exemplify this. Observations of numerous smaller faults in the diatomite quarry also show a dominant pattern of NW/SE-striking faults. E/W-striking compressional structures are present, but are less abundant. Faults of differing orientations occur together in the quarry and occasionally cross cut one another. Many faults cross but do not offset each other, indicating that they formed simultaneously. Where cross-cutting faults do exhibit offset, the NW/SE-striking faults offset E/W-striking faults, which suggests that NW/SE oriented faults have been longer lived or have had more recent activity. This relationship indicates that while the two main faulting patterns did coexist for a period of time, NW/SE-striking faults continued to deform after E/W features shut off.

  11. USGS Red River of the North at Fargo Streamgage

    Water level measurement from the USGS Red River of the North at Fargo streamgage in downtown Fargo, ND. The water level peaked at around 39 feet at this streamgage on April 9. Real-time water level and streamflow data from this gage can be accessed online....

  12. Quantifying Morphologic Changes in a Low Gradient River Crossing Southeast Louisiana Fault Zones

    NASA Astrophysics Data System (ADS)

    Fischer, G.; Gasparini, N. M.; Dawers, N. H.

    2011-12-01

    This study investigates the signature of faulting in low gradient, alluvial rivers crossing the Baton Rouge fault zone (BRFZ) and Denham Springs-Scotlandville fault zone (DSSFZ), which encompass a set of East-West striking normal faults in southeast Louisiana. These faults exhibit surface expressions associated with up to a few meters of vertical displacement of Late Pleistocene sediments, but little is known about their activity during the Holocene. Our study aims to quantify geomorphic changes in a number of rivers that cross these fault zones and to use these changes to gain insight into the history of faulting in the region. We hypothesize that fault movement will be evident in patterns of river sinuosity, slope, and width to depth ratio. We focus on four subparallel channels of various discharges that cross either or both the BRFZ and the DSSFZ. Information on local fault scarp heights and channel reaches are extracted by GIS analysis of the LA LiDAR 5 m DEM, as well as flow modeling using the HEC-RAS software program. On the Tickfaw River, we conducted field surveys using differential GPS to record contemporary water surface slopes and channel location. Historic channel features on the Tickfaw are characterized using a series of aerial photographs dating back to 1952. Over the past 50 years, the Tickfaw River has shortened its course through the study area significantly (~4.9%) by means of meander cutoffs. Since 1952, sinuosity (P) has decreased in all of the Tickfaw channel reaches that cross fault segments. Currently, the sinuosity is extremely low (average P = 1.14) where the river crosses the DSSFZ and slightly higher where the river crosses the BRFZ (average P = 1.9). We use the LiDAR data to quantify offset on the faults that the river crosses. These values will be compared with the average lateral migration rate of the river in order to better understand the time scales over which both processes operate. If the faults appear to have little morphologic impact on the river, it is likely that that fluvial migration rates are rapid enough to erase any signature of the accumulated throw from the faults. With continued analysis, our goal is to develop a reliable method for using alluvial rivers to help unravel the history of fault systems in low gradient landscapes, with possible applications for detecting regions vulnerable to fault-related subsidence.

  13. 78 FR 62359 - Red River Hydro LLC; Notice of Availability of Final Environmental Assessment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-21

    ..., 52 FR 47897), the Office of Energy Projects has reviewed Red River Hydro LLC's application for an... Energy Regulatory Commission Red River Hydro LLC; Notice of Availability of Final Environmental... prepared a final environmental assessment (EA). The project would be located on the Red River in...

  14. 33 CFR 165.T09-0260 - Safety zone; Red River.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Safety zone; Red River. 165.T09... Navigation Areas and Limited Access Areas Ninth Coast Guard District § 165.T09-0260 Safety zone; Red River. (a) Location. The following area is a safety zone: Waters of the Red River in the State of...

  15. 78 FR 36767 - Red River Hydro LLC; Notice of Availability of Draft Environmental Assessment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-19

    ..., 52 FR 47897), the Office of Energy Projects has reviewed Red River Hydro LLC's application for an... Energy Regulatory Commission Red River Hydro LLC; Notice of Availability of Draft Environmental... prepared a draft environmental assessment (draft EA). The project would be located on the Red River...

  16. 76 FR 49462 - Red River Hydro LLC; Notice of Application Tendered For Filing With the Commission and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-10

    ... Energy Regulatory Commission Red River Hydro LLC; Notice of Application Tendered For Filing With the.... Date Filed: July 29, 2011. d. Applicant: Red River Hydro LLC (Red River), a wholly-owned subsidiary of... would be located on the Red River in Rapides Parish, Louisiana at an existing lock and dam owned...

  17. 77 FR 34371 - Red River Hydro LLC; Notice of Application Tendered for Filing With the Commission and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-11

    ... Energy Regulatory Commission Red River Hydro LLC; Notice of Application Tendered for Filing With the.... c. Date Filed: May 24, 2012. d. Applicant: Red River Hydro LLC (Red River), a wholly-owned...: The project would be located on the Red River in Rapides Parish, Louisiana at an existing lock and...

  18. 75 FR 54026 - Safety Zone; Red Bull Flugtag, Delaware River, Camden, NJ

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-03

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Red Bull Flugtag, Delaware River, Camden... portion of the Delaware River during the Red Bull Flugtag event. The safety zone is necessary to protect... vessels and vessels from any debris in the water as a result from the event. Basis and Purpose Red...

  19. 76 FR 22033 - Safety Zone; Red River Safety Zone, Red River, MN

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-20

    ... latitude 46 20'00'' N, including those portions of the river in Wilkin, Clay, Norman, Polk, Marshall and... of Minnesota north of a line drawn across latitude 46 20'00'' N, including those portions of...

  20. Quality of water in the Red River alluvial aquifer; Pool 1, Red River waterway area, Vick, Louisiana

    USGS Publications Warehouse

    Smoot, C.W.; Seanor, R.C.; Huff, G.F.

    1994-01-01

    Water-quality changes in the Red River alluvial aquifer within the area affected by pool 1 near Vick, Louisiana, were monitored during pre-construction (1974-78) and post-construction (1984-92) of Lock and Dam 1. Changes greater or less than background values have occurred in an area within 2 miles of Lock and Dam 1, and in one well located about 10 miles west of Lock and Dam 1. Comparison between the pre-construction and post-construction water-quality analyses indicated the total hardness as calcium carbonate and concentrations of dissolved chloride, iron, and manganese generally have decreased in the Red River alluvial aquifer south of the Red River and near Lock and Dam l. The maximum decrease of the median total hardness as calcium carbonate was from 730 to 330 mg/L (milligrams per liter), dissolved chloride from 77 to 46 mg/L, dissolved iron from 18 to 6.9 mg/L, and dissolved manganese from 1.4 to 0.56 mg/L. Analyses of water from wells west of Lock and Dam 1 indicated an increase of the median total hardness as calcium carbonate was from 200 to 260 mg/L, and dissolved iron concentration was from 0.33 to 1.4 mg/L. North of the river and 1 mile west of Lock and Dam l, the median concentration of dissolved chloride increased from 45 to 130 mg/L in water from one well, and median total hardness as calcium cabonate and concentrations of dissolved iron and manganese also increased. Because well Ct-74 is completed in a sand that is in contact with a saltwater sand of Tertiary age, this increase is probably a temporal increase due to upconing after lowering the water level in the alluvial aquifer by pumping of dewatering wells during construction of Lock and Dam 1.

  1. Simple shear detachment fault system and marginal grabens in the southernmost Red Sea rift

    NASA Astrophysics Data System (ADS)

    Tesfaye, Samson; Ghebreab, Woldai

    2013-11-01

    The NNW-SSE oriented Red Sea rift, which separates the African and Arabian plates, bifurcates southwards into two parallel branches, southeastern and southern, collectively referred to as the southernmost Red Sea rift. The southern branch forms the magmatically and seismo-tectonically active Afar rift, while the less active southeastern branch connects the Red Sea to the Gulf of Aden through the strait of Bab el Mandeb. The Afar rift is characterized by lateral heterogeneities in crustal thickness, and along-strike variation in extension. The Danakil horst, a counterclockwise rotating, narrow sliver of coherent continental relic, stands between the two rift branches. The western margin of the Afar rift is marked by a series of N-S aligned right-lateral-stepping and seismo-tectonically active marginal grabens. The tectonic configuration of the parallel rift branches, the alignment of the marginal grabens, and the Danakil horst are linked to the initial mode of stretching of the continental crust and its progressive deformation that led to the breakup of the once contiguous African-Arabian plates. We attribute the initial stretching of the continental crust to a simple shear ramp-flat detachment fault geometry where the marginal grabens mark the breakaway zone. The rift basins represent the ramps and the Danakil horst corresponds to the flat in the detachment fault system. As extension progressed, pure shear deformation dominated and overprinted the initial low-angle detachment fault system. Magmatic activity continues to play an integral part in extensional deformation in the southernmost Red Sea rift.

  2. A History of Flooding in the Red River Basin

    USGS Publications Warehouse

    Ryberg, Karen R.; Macek-Rowland, Kathleen M.; Banse, Tara A.; Wiche, Gregg J.

    2007-01-01

    The U.S. Geological Survey (USGS), one of the principal Federal agencies responsible for the collection and interpretation of water-resources data, works with other Federal, State, local, tribal, and academic entities to ensure that accurate and timely data are available for making decisions regarding public welfare and property during natural disasters and to increase public awareness of the hazards that occur with such disasters. The Red River of the North Basin has a history of flooding and this poster is designed to increase public awareness of that history and of the factors that contribute to flooding.

  3. Hosgri fault zone, offshore Santa Maria River to Point Arguello, California

    SciTech Connect

    Cummings, D.; Gaal, R.A.

    1987-05-01

    The Hosgri fault zone between the Santa Maria River and Point Arguello was studied using 1280 line km of digital CDP seismic reflection and analog seismic reflection data. The fault zone is interpreted as (1) being high angle within the upper 1.5 sec two-way traveltime (approximately 2500 m); (2) having apparent reverse displacement, east block relatively up; and (3) based on subbottom and 3.5-kHz data, not cutting apparent unconsolidated (assumed Quaternary) sediments. The fault zone is well defined at the north end of the survey area, 12 km offshore, where it consists of two subparallel faults. Although the apparent vertical offset in this area is reasonably distinct, the amount of strike-slip displacement could not be determined from the available data because of the absence of well-defined piercing points. These two faults curve eastward near 34/sup 0/40'N and latitude and horsetail, striking onshore between 34/sup 0/38'N and 34/sup 0/40'N latitude. These faults may be the offshore extensions of the Lompoc-Solvang fault on the south and one of the (buried) Santa Ynez River faults on the north.

  4. Quaternary faulting of basalt flows on the Melones and Almanor fault zones, North Fork Feather River, northeastern California

    SciTech Connect

    Wakabayashi, J. , Hayward, CA ); Page, W.D. . Geosciences Dept.)

    1993-04-01

    Field relations indicate multiple sequences of late Cenozoic basalt flowed down the canyon of the North Fork Feather River from the Modoc Plateau during the Pliocene and early Quaternary. Remnants of at least three flow sequences are exposed in the canyon, the intermediate one yielding a K/Ar plagioclase date of 1.8 Ma. Topographic profiling of the remnants allows identification of Quaternary tectonic deformation along the northern Plumas trench, which separates the Sierra Nevada from the Diamond Mountains. The authors have identified several vertical displacements of the 1.8-Ma unit in the North Fork canyon and the area NE of Lake Almanor. NE of the lake, three NW-striking faults, each having down-to-the-west displacements of up to 35 m, are related to faulting along the east side of the Almanor tectonic depression. Analysis of the displaced basalt flows suggests that uplift of the Sierra Nevada occurred with canyon development prior to 2 Ma, and has continued coincident with several subsequent episodes of basalt deposition. Quaternary faulting of the basalt is associated with the Melones fault zone and the Plumas trench where they extend northward from the northern Sierra Nevada into the Modoc Plateau and southern Cascades. In contrast to the Mohawk Valley area, where the Plumas trench forms a 5-km-wide graben, faulting in the Almanor region is distributed over a 15-km-wide zone. A change in the strike of faulting occurs at Lake Almanor, from N50W along the Plumas trench to N20W north of the lake. The right-slip component on the fault of the Plums trench may result in a releasing bend at the change in strike and explain the origin of the Almanor depression.

  5. Evolution of regional stresses based on faulting and folding near the Pit River, Shasta County, California

    NASA Astrophysics Data System (ADS)

    Austin, L. J.; Weldon, R. J.

    2013-12-01

    We investigate the evolution of the regional stress state near the Pit River, northeastern California, by analyzing faults and folds preserved in and adjacent to a diatomite mine north of the Pit River near Burney. By measuring the orientation of 250 faults and 140 kinematic indicators on fault planes, we have determined principal stress directions preserved during the past million years. We observe the best exposures of faults in the diatomite mine, a paleolake deposit with an age tightly constrained by 1045 ka volcanic rocks below and the 973 ka Pole Creek basalt above (Muffler et al, 2012). To ensure a regionally representative analysis, we also include faults from the surrounding area, which are sparse but show consistent results. If we analyze all of the high angle faults as a single heterogeneous set, we find a stress state that would produce right-lateral strike-slip faulting on a moderately dipping southeast-striking fault plane. When we break the faults into groups based on orientation and include very low angle faults, we see an evolution of the stress state through time. The maximum principal stress directions (sigma 1) for the groups cluster along a north-south axis, and the lesser principal stresses (sigma 2 and sigma 3) are distributed along an east-west axis. Because moderately-dipping faults have strikes subparallel to regional normal faults and have kinematic indicators that are both down dip and parallel to strike, we infer that normal faulting occurred first and that some normal faults have been reactivated as strike slip faults. Because low angle faults form a distinct conjugate set and cut or deform high angle faults, we infer that they are the youngest. Low angle faults cluster into two groups that dip shallowly to the northwest and southwest. Analysis of the two groups as a conjugate set is consistent with individual analysis of each, and the slip vectors for the two groups cluster around the intersection with the sigma 1-3 plane. This would be very unlikely if low angle faults were simply accommodation structures or due to landsliding or compaction. High precision survey data along marker beds in the diatomite mine show at least two generations of subtle folding, which is distinct from the pre-paleolake basement topography. On a stereonet, poles to bedding planes in the diatomite cluster neatly along two great circles that define two fold axes. Folds are roughly orthogonal and trend southeast and southwest, plunging gently 2-4 degrees. We infer that the southeast generation of folds formed with other fault-parallel folds associated with normal faults in the region, such as the nearby Five Corners monocline. Evolution at this site through time is consistent with the spatial distribution of stress states at the northwest end of Walker Lane. We observe domains of normal faulting generally to the west, strike-slip faulting to the southeast, and reverse faulting to the northwest.

  6. 33 CFR 208.26 - Altus Dam and Reservoir, North Fork Red River, Okla.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false Altus Dam and Reservoir, North Fork Red River, Okla. 208.26 Section 208.26 Navigation and Navigable Waters CORPS OF ENGINEERS..., North Fork Red River, Okla. The Bureau of Reclamation, or its designated agent, shall operate the...

  7. 75 FR 17106 - Safety Zone; Red Bull Air Race, Detroit River, Detroit, MI

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-05

    ..., 2008 issue of the Federal Register (73 FR 3316). Public Meeting We do not now plan to hold a public... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Red Bull Air Race, Detroit River, Detroit... vessels from portions of the Detroit River during the Red Bull Air Race. This temporary safety zone...

  8. 75 FR 30708 - Safety Zone; Red Bull Air Race, Detroit River, Detroit, MI

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-02

    ... Federal Register (75 FR 17106). We received zero comments on the proposed rule. No public meeting was... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Red Bull Air Race, Detroit River, Detroit... from portions of the Detroit River during the Red Bull Air Race. This temporary safety zone...

  9. 33 CFR 208.26 - Altus Dam and Reservoir, North Fork Red River, Okla.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Altus Dam and Reservoir, North Fork Red River, Okla. 208.26 Section 208.26 Navigation and Navigable Waters CORPS OF ENGINEERS..., North Fork Red River, Okla. The Bureau of Reclamation, or its designated agent, shall operate the...

  10. 33 CFR 208.26 - Altus Dam and Reservoir, North Fork Red River, Okla.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Altus Dam and Reservoir, North Fork Red River, Okla. 208.26 Section 208.26 Navigation and Navigable Waters CORPS OF ENGINEERS..., North Fork Red River, Okla. The Bureau of Reclamation, or its designated agent, shall operate the...

  11. 33 CFR 208.26 - Altus Dam and Reservoir, North Fork Red River, Okla.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 3 2013-07-01 2013-07-01 false Altus Dam and Reservoir, North Fork Red River, Okla. 208.26 Section 208.26 Navigation and Navigable Waters CORPS OF ENGINEERS..., North Fork Red River, Okla. The Bureau of Reclamation, or its designated agent, shall operate the...

  12. 33 CFR 208.26 - Altus Dam and Reservoir, North Fork Red River, Okla.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Altus Dam and Reservoir, North Fork Red River, Okla. 208.26 Section 208.26 Navigation and Navigable Waters CORPS OF ENGINEERS..., North Fork Red River, Okla. The Bureau of Reclamation, or its designated agent, shall operate the...

  13. Statistical Correlation between Red Wood Ant Sites and Neotectonic Strike-Slip Faults

    NASA Astrophysics Data System (ADS)

    Berberich, G.; Klimetzek, D.; Wöhler, C.; Grumpe, A.

    2012-04-01

    Recent research in the West Eifel (West Germany) has demonstrated the correlation of soil gas anomalies and spatial distribution of red wood ant (RWA) mounds along strike-slip faults. RWA can be used as biological indicators for the identification of neotectonic fault systems (Berberich 2010, Schreiber & Berberich 2011). For myrmecologists, the causes and stringency of such a linkage are paramount, since linear patterns have been mostly associated with edge effects of forest stands and/or roads (Klimetzek 1970, Klimetzek & Kaiser 1995, Wellenstein 1990). Therefore, geostatistical techniques were applied in the West Eifel and the Bodanrück (South West Germany) to distribution data of approx. 3,000 resp. 2,300 mounds of RWA (Formica spp., Hymenoptera: Formicidae) in correlation with known neotectonic fault systems Both study areas are located in areas with a complex tectonic history. Commenced during the Neogene and persisted during the Quaternary, the uplift of both, the Rhenoherzynikum and the Black Forest, affects the dynamics of the study areas and reactivates pre-existing Palaeozoic crustal discontinuities. The West Eifel (Rhenoherzynikum) was tectonically sheared in Mesozoic and Cenozoic times. The current NW-SE-trending main stress direction opens pathways for geogenic gases. At the same time, Variscan faults as part of a conjugated shear system, are reactivated. At the Bodanrück, the compressional stress field (NNW-SSE) leads to a WSW-ENE extensional regime, in which faults cut through the entire crust (Ziegler & Dèzes 2007, Nagra 1992). The prominent large-scale neotectonic structure is the NW-SE to WNW-ESE trending "Freiburg-Bonndorf-Hegau-Bodensee-Graben" that consists of several sub-trenches (Müller et al. 2002). Field surveys indicate a possible existence of a NNE-SSW trending strike-slip fault extending east of Stein am Rhein (Büchi & Müller 2003) possibly reactivated in the Quaternary (Birkhäuser et al. 2001). Available focal mechanism solutions show a lack of possible fault planes striking between 40 and 90 degrees from north (Deichmann 1990). In addition, a NNW-SSE and NS trending fault system exist. We tested the hypothesis that the spatial distribution of RWA mounds would map the neotectonic stress field directly (Berberich et al. 2012). A statistical method for the automatic extraction of linear patterns from point clouds (Hough transform) was applied to the spatial distribution of RWA mounds. The maxima of the resulting histograms denote the preferential alignment directions. In both cases, it could be clearly shown that the spatial distribution of RWA mounds directly map the main stress field and the conjugated shear system in hierarchically succession. In the West Eifel, RWA depict mainly the opening direction of the Quaternary volcanic field (NW-SE), the WSW-ENE extensional regime and the reactivated Variscan fault systems (NNE-SSW, NE-SW). At the Bodanrück, the hypothesized existence of the NNE-SSW strike-slip fault systems (Büchi & Müller 2003) and additionally NE-SW, NNW-SSE and NS directions could be demonstrated. In conclusion, the statistical analyses show that spatial distribution of RWA maps neotectonic, gaspermeable strike-slip faults. This is especially useful in those cases, where information about the neotectonic regime is incomplete or the resolution by technical means is insufficient.

  14. Does Karakorum Fault Cut Across the Great Himalaya? Findings of Strike Slip Active Fault Along the Humla-Karnali River in the Northwestern Part of Nepal

    NASA Astrophysics Data System (ADS)

    Kumahara, Y.; Maemoku, H.; Yagi, H.; Nagatomo, T.; Upreti, B. N.

    2005-12-01

    It is well known that collision between the Indian and the Eurasian plates does not cause only mega thrusting along the Himalayan front but also great strike-slip shear or N-S extensional zones in the Tibetan block. Active tectonics of Tibet is presumed to be extrusion of Tibetan block along great strike-slip faults such as the Altyn Tagh and the Kunlun faults and consequent evolution of normal faults of N-S direction in the tensional stress field. The Karakorum fault seems to be terminated by Himalayan range on its southeastern edge (Searle,1996). As a southeastern extension of the fault, we found a new fault named Yari fault that was strike-slip fault across the Great Himalayan Range along Humla-Karnali River using a method of photo interpretation of aerial photographs and US spy satellite images. Nakata (1989) showed that MCT (Main Central Trust) active fault system and Bari Gad fault which is located within the Lesser Himalaya of western Nepal are right-stepping echelon striking NW- SE for 170km based on photo interpretation and fieldwork, and also pointed out that those could connect to the Karakoram fault system. There was, however, a gap for about 100 km between the Karakoram fault and the northernmost of the MCT active fault system. In 1990_fs, the Topological Survey of Nepal took vertical air photographs covered all the territory with the aim of publishing topographical maps. With using those new aerial photographs, we recognized an active fault cutting the Great Himalaya in the northwestern Nepal up to the international border of China as NW extension of the MCT active fault system. It is named Yari fault after nearest village name, which has single trace for 50km striking NW-SE generally. In the east of Yari village, alluvial fans and river terraces of different age have been displaced along the fault trace continuously with marked by north-facing scarp and right-lateral offset stream. Yari fault should play very important role as a bridge connecting Karakorum fault on the north of Himalaya and MCT (Main Central Trust) active fault system that is located along the topographical boundary of Higher Himalaya and Lower Himalaya. We would like to establish a hypothesis that not only Tibetan block but also Himalayan ranges are being divided by a series of strike-slip faults such as those strike-slip faults and extruded eastward.

  15. GeoBioScience: Red Wood Ants as Bioindicators for Active Tectonic Fault Systems in the West Eifel (Germany)

    PubMed Central

    Berberich, Gabriele; Schreiber, Ulrich

    2013-01-01

    Simple Summary In a 1.140 km² study area of the volcanic West Eifel, approx. 3,000 Red Wood Ant (RWA; Formica rufa-group) mounds had been identified and correlated with tectonically active gas-permeable faults, mostly strike-slip faults. Linear alignment of RWA mounds and soil gas anomalies distinctly indicate the course of these faults, while clusters of mounds indicate crosscut zones of fault systems, which can be correlated with voids caused by crustal block rotation. This demonstrates that RWA are bioindicators for identifying active fault systems and useful where information on the active regime is incomplete or the resolution by technical means is insufficient. Abstract In a 1.140 km² study area of the volcanic West Eifel, a comprehensive investigation established the correlation between red wood ant mound (RWA; Formica rufa-group) sites and active tectonic faults. The current stress field with a NW-SE-trending main stress direction opens pathways for geogenic gases and potential magmas following the same orientation. At the same time, Variscan and Mesozoic fault zones are reactivated. The results showed linear alignments and clusters of approx. 3,000 RWA mounds. While linear mound distribution correlate with strike-slip fault systems documented by quartz and ore veins and fault planes with slickensides, the clusters represent crosscut zones of dominant fault systems. Latter can be correlated with voids caused by crustal block rotation. Gas analyses from soil air, mineral springs and mofettes (CO2, Helium, Radon and H2S) reveal limiting concentrations for the spatial distribution of mounds and colonization. Striking is further the almost complete absence of RWA mounds in the core area of the Quaternary volcanic field. A possible cause can be found in occasionally occurring H2S in the fault systems, which is toxic at miniscule concentrations to the ants. Viewed overall, there is a strong relationship between RWA mounds and active tectonics in the West Eifel. PMID:26487413

  16. 77 FR 14965 - Special Local Regulations; Red Bull Candola, New River, Fort Lauderdale, FL

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-14

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulations; Red Bull Candola, New River... east of the South Andrews Avenue Bascule Bridge in Fort Lauderdale, Florida for the Red Bull Candola... this rule because the Coast Guard did not receive necessary information about the Red Bull...

  17. Seismic Reflection Project Near the Southern Terminations of the Lost River and Lemhi Faults, Eastern Snake River Plain, Idaho

    SciTech Connect

    S. M. Jackson; G. S. Carpenter; R. P. Smith; J. L. Casper

    2006-10-01

    Thirteen seismic reflection lines were processed and interpreted to determine the southern terminations of the Lost River and Lemhi faults along the northwest boundary of the eastern Snake River Plain (ESRP). The southernmost terminations of the Arco and Howe segments were determined to support characterization of the Lost River and Lemhi fault sources, respectively, for the INL probabilistic seismic hazard analysis. Keywords:Keywords are required forExternal Release Review*Keywords  Keywords *Contacts (Type and Name are required for each row) Type ofContactContact Name  POC Editor RecordFour commercial seismic reflection lines (Arco lines 81-1 and 81-2; Howe lines 81-3 and 82-2) were obtained from the Montana Power Company. The seismic data were collected in the early 1980’s using a Vibroseis source with station and shot point locations that resulted in 12-fold data. Arco lines 81?1 and 81?2 and Howe lines 81?3 and 82?2 are located within the basins adjacent to the Arco and Howe segments, respectively. Seven seismic lines (Arco lines A1, A2, A3, and A4 and Howe lines H1, H2, and H3) were acquired by EG&G Idaho, Inc. Geosciences for this study using multiple impacts with an accelerated weight drop source. Station and shot point locations yielded 12-fold data. The seismic reflection lines are oriented perpendicular to and at locations along the projected extensions of the Arco and Howe fault segments within the ESRP. Two seismic lines (Arco line S2 and Howe line S4) were obtained from Sierra Geophysics. In 1984, they acquired seismic reflection data using an accelerated weight drop source with station and shot point locations that yielded 6-fold data. The two seismic reflection lines are oriented perpendicular to and at locations along the projected extensions of the Arco and Howe fault segments within the ESRP. In 1992 for this study, Geotrace Technologies Inc. processed all of the seismic reflection data using industry standard processing techniques. The southern termination of the Howe segment of the Lemhi fault was placed between Howe lines H1 and H2, 2.2 km south of the fault’s southernmost surface expression. In the adjacent basin, south-dipping normal faults at the northern end of Howe line 81-3 and two southwest-dipping normal faults at the northeastern end of Howe line 82-2 that can be correlated with Howe segment. South of the surface expression, two southwest-dipping normal faults on Howe line H1 can be correlated with the Howe segment. Further into the ESRP, Howe lines H2, H3, and S4 show continuous flat lying reflectors and indicate no fault offset. The southern termination of the Arco segment of the Lost River fault was placed between Arco lines S2 and A3, a distance of 4.6 km south of the fault’s southernmost surface expression. Within the basin, west-dipping normal faults interpreted on Arco lines 81-1 and 81-2 can be correlated with the Arco segment. Further south within the Arco volcanic rift zone (VRZ), three seismic lines (Arco lines A2, S2, and A3) permit two interpretations. The west- and south-dipping normal faults on Arco lines A2 and S2 could be associated with slip along the Arco segment. These normal faults have an opposite dip to an east-dipping fault on Arco line A3. The observed small-offsets (< 85 m) along the oppositely dipping normal faults can be interpreted as a graben structure that resulted from dike intrusion within the Arco VRZ. Arco line A4 further south within the Arco VRZ shows flat lyin

  18. Establishing river basin organisations inVietnam: Red River, Dong Nai River and Lower Mekong Delta.

    PubMed

    Taylor, P; Wright, G

    2001-01-01

    River basin management is receiving considerable attention at present. Part of the debate, now occurring worldwide, concerns the nature of the organisations that are required to manage river basins successfully, and whether special-purpose river basin organisations (RBOs) are always necessary and in what circumstance they are likely to (i) add to the management of the water resources and (ii) be successful. The development of river basin management requires a number of important elements to be developed to a point where the river basin can be managed successfully. These include the relevant laws, the public and non-government institutions, the technical capabilities of the people, the understanding and motivation of people, and the technical capacity and systems, including information. A river basin organisation (or RBO) is taken to mean a special-purpose organisation charged with some part of the management of the water resources of a particular river basin. Generally speaking, such organisations are responsible for various functions related to the supply, distribution, protection and allocation of water, and their boundaries follow the watershed of the river in question. However, the same functions can be carried out by various organisations, which are not configured on the geographical boundaries of a river basin. This paper outlines recent work on river basin organisation in Vietnam, and makes some comparisons with the situation in Australia. PMID:11419135

  19. Borderline science: expert testimony and the Red River boundary dispute.

    PubMed

    Cittadino, Eugene

    2004-06-01

    The 1918 discovery of oil in the bed of the Red River, which forms the border between Texas and Oklahoma, led to a U.S. Supreme Court case that involved the extensive use of expert witnesses in fields such as geology, geography, and ecology. What began as a dispute between the two states soon became a multisided controversy involving those states, the federal government, Native Americans, and individual placer-mining claimants. After the federal attorneys introduced scientific experts into the dispute, including the plant ecologist Henry Chandler Cowles and the geographer Isaiah Bowman, fresh from negotiations at the Paris Peace Conference, Texas attorneys fielded their own team of opposing experts. Charged with the task of determining the location of the border, defined as the south bank of the river at the time of the 1819 treaty with Spain, the scientific experts presented the court with volumes of evidence and elaborate arguments, much of it contradictory and involving creative interpretations of existing theories. The case exhibited all the now-familiar features of a trial using expert witnesses, for which it represents an early, overlooked, and particularly complex example. PMID:15490965

  20. 77 FR 24949 - Red River Lock & Dam No. 4 Hydroelectric Project; BOST4 Hydroelectric LLC; Notice of Proposed...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-26

    ... Energy Regulatory Commission Red River Lock & Dam No. 4 Hydroelectric Project; BOST4 Hydroelectric LLC... affected by issuance of a license for the proposed Red River Lock & Dam No. 4 Hydroelectric Project No... Hydroelectric LLC, as applicant for the proposed Red River Lock & Dam No. 4 Project No. 12757, is invited...

  1. Basement Surface Faulting and Topography for Savannah River Site and Vicinity

    SciTech Connect

    Cumbest, R.J.

    1998-12-17

    This report integrates the data from more than 60 basement borings and over 100 miles of seismic reflection profiling acquired on the Savannah River Site to map the topography of the basement (unweathered rock) surface and faulting recorded on this surface.

  2. Map of the Rinconada and Reliz Fault Zones, Salinas River Valley, California

    USGS Publications Warehouse

    Rosenberg, Lewis I.; Clark, Joseph C.

    2009-01-01

    The Rinconada Fault and its related faults constitute a major structural element of the Salinas River valley, which is known regionally, and referred to herein, as the 'Salinas Valley'. The Rinconada Fault extends 230 km from King City in the north to the Big Pine Fault in the south. At the south end of the map area near Santa Margarita, the Rinconada Fault separates granitic and metamorphic crystalline rocks of the Salinian Block to the northeast from the subduction-zone assemblage of the Franciscan Complex to the southwest. Northwestward, the Rinconada Fault lies entirely within the Salinian Block and generally divides this region into two physiographically and structurally distinct areas, the Santa Lucia Range to the west and the Salinas Valley to the east. The Reliz Fault, which continues as a right stepover from the Rinconada Fault, trends northwestward along the northeastern base of the Sierra de Salinas of the Santa Lucia Range and beyond for 60 km to the vicinity of Spreckels, where it is largely concealed. Aeromagnetic data suggest that the Reliz Fault continues northwestward another 25 km into Monterey Bay, where it aligns with a high-definition magnetic boundary. Geomorphic evidence of late Quaternary movement along the Rinconada and Reliz Fault Zones has been documented by Tinsley (1975), Dibblee (1976, 1979), Hart (1976, 1985), and Klaus (1999). Although definitive geologic evidence of Holocene surface rupture has not been found on these faults, they were regarded as an earthquake source for the California Geological Survey [formerly, California Division of Mines and Geology]/U.S. Geological Survey (CGS/USGS) Probabilistic Seismic Hazards Assessment because of their postulated slip rate of 1+-1 mm/yr and their calculated maximum magnitude of 7.3. Except for published reports by Durham (1965, 1974), Dibblee (1976), and Hart (1976), most information on these faults is unpublished or is contained in theses, field trip guides, and other types of reports. Therefore, the main purpose of this project is to compile and synthesize this body of knowledge into a comprehensive report for the geologic community. This report follows the format of Dibblee (1976) and includes discussions of the sections of the Rinconada Fault and of the Reliz Fault, as well as their Neogene history and key localities. Accompanying this report is a geologic map database of the faults, key localities, and earthquake epicenters, in ESRI shapefile format.

  3. Feedback between deformation and magmatism in the Lloyds River Fault Zone: An example of episodic fault reactivation in an accretionary setting, Newfoundland Appalachians

    NASA Astrophysics Data System (ADS)

    Lissenberg, C. Johan; van Staal, Cees R.

    2006-08-01

    The Lloyds River Fault Zone is a 10-15 km wide amphibolite-grade shear zone that formed during the Ordovician Taconic Orogeny. It separates ophiolites and arc-back-arc complexes formed in Iapetus from a peri-Laurentian microcontinent (Dashwoods microcontinent). The Lloyds River Fault Zone comprises three high-strain zones, dominantly composed of mylonitic amphibolites, separated by less deformed plutonic rocks. Structural, age and metamorphic data suggest the Lloyds River Fault Zone accommodated sinistral-oblique underthrusting of ophiolites underneath the Dashwoods microcontinent prior to 471 ± 5 Ma at 800°C and 6 kbar. Plutonic rocks within the Lloyds River Fault Zone comprise two suites dated at 464 ± 2 plus 462 ± 2 and 459 ± 3 Ma, respectively. The younger age of the plutons with respect to some of the amphibolites, evidence for magmatic deformation, and the elongate nature of the plutons parallel to the Lloyds River Fault Zone suggest they were emplaced within the fault zone during deformation. Both intrusive episodes triggered renewed deformation at high temperatures (770-750°C), illustrating the positive feedback between deformation and magmatism. Offshoots of the plutons intruded undeformed ophiolitic gabbros outside the Lloyds River Fault Zone. Deformation localized within the intrusive sheets, coeval with static contact metamorphism of the host gabbros, leading to the development of new, small-scale shear zones. This illustrates that channeling of plutons into shear zones and nucleation of shear zones in melt-rich zones may occur simultaneously within the same fault system.

  4. Red River Stream Improvement Final Design Nez Perce National Forest.

    SciTech Connect

    Watershed Consulting, LLC

    2007-03-15

    This report details the final stream improvement design along the reach of Red River between the bridge below Dawson Creek, upstream for approximately 2 miles, Idaho County, Idaho. Geomorphic mapping, hydrologic profiles and cross-sections were presented along with existing fish habitat maps in the conceptual design report. This information is used to develop a stream improvement design intended to improve aquatic habitat and restore riparian health in the reach. The area was placer mined using large bucket dredges between 1938 and 1957. This activity removed most of the riparian vegetation in the stream corridor and obliterated the channel bed and banks. The reach was also cut-off from most valley margin tributaries. In the 50 years since large-scale dredging ceased, the channel has been re-established and parts of the riparian zone have grown in. However, the recruitment of large woody debris to the stream has been extremely low and overhead cover is poor. Pool habitat makes up more than 37% of the reach, and habitat diversity is much better than the project reach on Crooked River. There is little large woody debris in the stream to provide cover for spawning and juvenile rearing, because the majority of the woody debris does not span a significant part of the channel, but is mainly on the side slopes of the stream. Most of the riparian zone has very little soil or subsoil left after the mining and so now consists primarily of unconsolidated cobble tailings or heavily compacted gravel tailings. Knapweed and lodgepole pine are the most successful colonizers of these post mining landforms. Tributary fans which add complexity to many other streams in the region, have been isolated from the main reach due to placer mining and road building.

  5. Streamflow losses along the Balcones Fault Zone, Nueces River basin, Texas

    USGS Publications Warehouse

    Land, L.F.; Boning, C.W.; Harmsen, Lynn; Reeves, R.D.

    1983-01-01

    An investigation was conducted to quantify and to determine distribution of streamflow losses and gains that occur during base flow conditions in the Balcones Fault Zone of the Neuces River basin. The streams studied include the West Nueces, Nueces , Dry Frio, Frio, and Sabinal Rivers, and Seco, Hondo, and Verde Creeks. Discharge measurements made during storm recession flows of these streams identified direct recharge to outcrops of the Edwards aquifer and related limestones that ranged from as high as 393 cubic feet per second for the Frio River to as low as 42 cubic feet per second for the Sabinal River. Recharge to outcrops of the Buda Limestone, Eagle Ford Shale, and Austin Group also eventually reaches the Edwards aquifer, and measurements identified losses to these formations ranging from as high as 174 cubic feet per second for the Frio River to near zero for Verde Creek. (USGS)

  6. No Red River capture since the late Oligocene: Geochemical evidence from the Northwestern South China Sea

    NASA Astrophysics Data System (ADS)

    Zhao, Meng; Shao, Lei; Liang, Jianshe; Li, Qianyu

    2015-12-01

    Rare earth elements (REE) in the sediment samples of six industrial wells from the Yinggehai-Song Hong Basin in the Northwestern South China Sea were analyzed and compared with the detrital zircon U-Pb data from earlier studies to extrapolate sediment provenance. The results reveal that the Red River (Song Hong River), Hainan Island and Central Vietnam have been the main provenances of the Yinggehai-Song Hong Basin since the late Oligocene. The Red River has been supplying sediments with positive Eu anomalies from basic-ultrabasic metamorphic and volcanic parent rocks to most parts of the basin, while Hainan Island has delivered sediments with negative Eu anomalies from granitic and sedimentary parent rocks to the eastern slope area of the basin. The progradational downlap structures in the seismic profiles also support the finding that the sediment supply is mainly from the Red River and from Hainan Island. The metamorphic rocks, which are widespread within the Red River drainage, not only provided high volumes of sediments to the basin but also contributed to the positive Eu anomalies observed. Because their REE and U-Pb signatures are similar to those of the Red River source, the metamorphic and igneous rocks of the Song Ma Suture Zone, Kontum Massif, and Jinghong area were probably parts of a large basic provenance region before being separated by strike-slip movements along the Ailao Shan-Red River shear zone. Furthermore, our results indicate that the Red River drainage area has been relatively stable since the late Oligocene. Therefore, if a drainage capture from the Red River occurred, it is likely to have taken place before the late Oligocene.

  7. Regional and local emissions in red river delta, Northern Vietnam.

    PubMed

    Bac, V T; Hien, P D

    2009-09-01

    Fine (PM(2.2)) and coarse (PM(2.2-10)) particles concurrently collected in urban (Hanoi) and rural (Lucnam) areas were analyzed for ionic and elemental compositions to provide input for PMF receptor modeling of emission sources in the Red River Delta (RRD), a key economic development region in Vietnam. Long-range transport (LRT) aerosol, coal fly ash from major coal-fired plants in RRD, and marine aerosols are regional sources, which explain the minor variability of the mass concentrations of fine particles across the region. Local sources include soil/resuspended road dust, local coal fly ash, and biomass burning. Soil/resuspended road dust is the largest source component of coarse particles at the two sites. It is more abundant in Hanoi than in Lucnam reflecting the urban-rural contrast in traffic and construction works. Receptor models reveal the incorporation of secondary sulfate, nitrate, and ammonium into the various primary particles, i.e., soot, minerals, soil organic matter, and sea salt. Soot particles from LRT carry the largest amounts of sulfate and ammonium mass concentrations measured at the two sites. Based on receptor models, the yields and possible chemical forms of secondary sulfate, nitrate, and ammonium in different types of primary particles can be inferred. PMID:19890405

  8. The Eastern Lower Tagus Valley Fault Zone in central Portugal: Active faulting in a low-deformation region within a major river environment

    NASA Astrophysics Data System (ADS)

    Canora, Carolina; Vilanova, Susana P.; Besana-Ostman, Glenda M.; Carvalho, João; Heleno, Sandra; Fonseca, Joao

    2015-10-01

    Active faulting in the Lower Tagus Valley, Central Portugal, poses a significant seismic hazard that is not well understood. Although the area has been affected by damaging earthquakes during historical times, only recently has definitive evidence of Quaternary surface faulting been found along the western side of the Tagus River. The location, geometry and kinematics of active faults along the eastern side of the Tagus valley have not been previously studied. We present the first results of mapping and paleoseismic analysis of the eastern strand of the Lower Tagus Valley Fault Zone (LTVFZ). Geomorphological, paleoseismological, and seismic reflection studies indicate that the Eastern LTVFZ is a left-lateral strike-slip fault. The detailed mapping of geomorphic features and studies in two paleoseismic trenches show that surface fault rupture has occurred at least six times during the past 10 ka. The river offsets indicate a minimum slip rate on the order of 0.14-0.24 mm/yr for the fault zone. Fault trace mapping, geomorphic analysis, and paleoseismic studies suggest a maximum magnitude for the Eastern LTVFZ of Mw ~ 7.3 with a recurrence interval for surface ruptures ~ 1.7 ka. At least two events occurred after 1175 ± 95 cal yr BP. Single-event displacements are unlikely to be resolved in the paleoseismic trenches, thus our observations most probably represent the minimum number of events identified in the trenches.

  9. 77 FR 43591 - Tri-State Financial Co., LLC, (d/b/a North Country Ethanol), Red River Energy, LLC; Notice of Filing

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-25

    ... Energy Regulatory Commission Tri-State Financial Co., LLC, (d/b/a North Country Ethanol), Red River... North Country Ethanol (Tri-State), and Red River Energy, LLC (Red River) filed an application, pursuant... No. CP05-75-000, and for Red River to acquire and operate Tri-State's facilities located in...

  10. Evolution of regional stress state based on faulting and folding near the pit river, Shasta county, California

    NASA Astrophysics Data System (ADS)

    Austin, Lauren Jean

    We investigate the evolution of the regional stress state near the Pit River, northern California, in order to understand the faulting style in a tectonic transition zone and to inform the hazard analysis of Fault 3432 near the Pit 3 Dam. By analyzing faults and folds preserved in and adjacent to a diatomite mine north of the Pit River, we have determined principal stress directions preserved during the past million years. We find that the stress state has evolved from predominantly normal to strike slip and most recently to reverse, which is consistent with regional structures such as the extensional Hat Creek Fault to the south and the compressional folding of Mushroom Rock to the north. South of the Pit River, we still observe normal and strike slip faults, suggesting that changes in stress state are moving from north to south through time.

  11. Earthquake fault superhighways

    NASA Astrophysics Data System (ADS)

    Robinson, D. P.; Das, S.; Searle, M. P.

    2010-10-01

    Motivated by the observation that the rare earthquakes which propagated for significant distances at supershear speeds occurred on very long straight segments of faults, we examine every known major active strike-slip fault system on land worldwide and identify those with long (> 100 km) straight portions capable not only of sustained supershear rupture speeds but having the potential to reach compressional wave speeds over significant distances, and call them "fault superhighways". The criteria used for identifying these are discussed. These superhighways include portions of the 1000 km long Red River fault in China and Vietnam passing through Hanoi, the 1050 km long San Andreas fault in California passing close to Los Angeles, Santa Barbara and San Francisco, the 1100 km long Chaman fault system in Pakistan north of Karachi, the 700 km long Sagaing fault connecting the first and second cities of Burma, Rangoon and Mandalay, the 1600 km Great Sumatra fault, and the 1000 km Dead Sea fault. Of the 11 faults so classified, nine are in Asia and two in North America, with seven located near areas of very dense populations. Based on the current population distribution within 50 km of each fault superhighway, we find that more than 60 million people today have increased seismic hazards due to them.

  12. Preconstruction and postconstruction ground-water levels, Lock and Dam 4, Red River Valley, Louisiana

    USGS Publications Warehouse

    Ludwig, A.H.; Reed, J.E.

    1979-01-01

    Proposed construction of a series of locks and dams in the Red River in Louisiana will cause a permanent increase in average river stage. The potentiometric surface of the shallow alluvial aquifer and the water table in the fine-grained material confining the aquifer will be affected. The purpose of this study, using digital-modeling techniques, was to predict the average postconstruction potentiometric surface (steady state) and the water table (nonsteady state) so that potential effects of the water-level changes could be evaluated. Plans for lock and dam 4 at realined mile 154 (kilometer 250) above the mouth of the Red River call for a pool elevation of 115 feet (35 meters) and will cause an average increase in river stage ranging from 24 to 4.5 feet (7 to 1.4 meters). As a result, ground-water levels will be raised 1 foot (0.3 meter) or more between the Red River and Bayou Pierre from the dam to Coushatta , and below Campti, east of the river. The potentiometric surface may be at or near land surface in low areas between the Red River and Bayou Pierre, and above land surface locally upstream from the dam. The magnitude of ground-water-level fluctuations near the river will be reduced to less than half the present range.

  13. Fan-delta and interdeltaic shoreline sediments of Middle Devonian Granite Wash and Keg River clastics, Red Earth field, north Alberta basin, Canada

    SciTech Connect

    Sabry, H.

    1989-03-01

    A detailed sedimentological investigation of over 4000 ft of core and 500 well logs of the Middle Devonian granite wash and Keg River clastics in the Red Earth field, North Alberta basin, Canada, has led to the recognition of a granite wash subaerial fan-delta system that is laterally continuous with a Keg River subaqueous delta component along an eastern shoreline of the ancestral Peace River arch. The subaerial fan delta includes alluvial fan facies, sheet wash and mud flows, and playa lakes. The subaqueous delta component includes lower shoreface, upper shoreface, beach-foreshore, eolian sand dunes, lagoon, washover sands, tidal channels and flats, and supratidal carbonates and anhydrites. Within this system, six mappable units are defined. A conceptual depositional model for the sequence depicts four main events. (1) Erosion of Peach River arch uplifted fault blocks, which produced coarse-grained fan-delta sediments in an adjacent fault-bounded margin. Subsequent fluvial reworking resulted in the deposition of thick, lenticular, wedge-shaped alluvial fans of granite wash. (2) Progradation of alluvial fans seaward into the Keg River Sea. (3) Transgression by Middle Devonian seas from the east, which reworked alluvial fans and led to deposition of discontinuous linear sand bodies represented by the Keg River regressive shoreline sediments. (4) Restriction of the sea by the Presqu'ile barrier reef to the north, which deposited evaporites of the Muskeg Formation over the whole sequence. Modern analog to this fan-delta system is the coastal fans of the Gulf of Aqaba, Red Sea. Red Earth field contains over 27 million bbl of recoverable oil, related to a combination structural-stratigraphic trap.

  14. 75 FR 16010 - Safety Zone; Red River, MN

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-31

    ... across latitude 46 20'00'' N, including those portions of the river in Wilkin, Clay, Norman, Polk...'' N, including those portions of the river in Wilkin, Clay, Norman, Polk, Marshall and Kittson... river in Wilkin, Clay, Norman, Polk, Marshall and Kittson counties, to the United...

  15. BLOOMING MECHANISM OF FRESHWATER RED-TIDE IN EUTRORHIC ABOLISHED-RIVER

    NASA Astrophysics Data System (ADS)

    Nagabayashi, Hisao; Hirayama, Kazuo; Horikawa, Kunihiko

    This paper analyzes blooming mechanism of freshwater red-tide in an abolished-river which eutrophicated by seventy-years. Outbreaks of red tide of the river is depend on two phenomenon; the first one is the effect of secondary current generated by the wind along with the temperature rise, the second is the flow for the downstream by the release discharge from the power generation-dam in the downstream. Euglena spp. in euglena and Uroglena spp. in yellow-zooxanthellas is clarified to be the dominant species of the freshwater red-tide.

  16. GeoBioScience: Red Wood Ants as Bioindicators for Active Tectonic Fault Systems in the West Eifel (Germany).

    PubMed

    Berberich, Gabriele; Schreiber, Ulrich

    2013-01-01

    In a 1.140 km² study area of the volcanic West Eifel, a comprehensive investigation established the correlation between red wood ant mound (RWA; Formica rufa-group) sites and active tectonic faults. The current stress field with a NW-SE-trending main stress direction opens pathways for geogenic gases and potential magmas following the same orientation. At the same time, Variscan and Mesozoic fault zones are reactivated. The results showed linear alignments and clusters of approx. 3,000 RWA mounds. While linear mound distribution correlate with strike-slip fault systems documented by quartz and ore veins and fault planes with slickensides, the clusters represent crosscut zones of dominant fault systems. Latter can be correlated with voids caused by crustal block rotation. Gas analyses from soil air, mineral springs and mofettes (CO₂, Helium, Radon and H₂S) reveal limiting concentrations for the spatial distribution of mounds and colonization. Striking is further the almost complete absence of RWA mounds in the core area of the Quaternary volcanic field. A possible cause can be found in occasionally occurring H₂S in the fault systems, which is toxic at miniscule concentrations to the ants. Viewed overall, there is a strong relationship between RWA mounds and active tectonics in the West Eifel. PMID:26487413

  17. Deep seated landslides along the Meilungshan fault in Laonung River Waterdhed, southern Taiwan

    NASA Astrophysics Data System (ADS)

    Ho, Dia-Jie; Lin, Ching-Weei; Tseng, Chih-Ming

    2013-04-01

    Landslides in Taiwan represent one of most relevant natural hazards for the society. In particular, the large scaled deep-seated landslides deserve attention, because they can be reactivated during intense events and can evolve into destructive failures. For example, one deep seated landslide, the Hsiaolin landslide, with an area of about 250 ha, buried the entire village of Hsiaolin in Kaohsiung County causing 397 causalities, the disappearance of 53 others, and buried over 100 houses during the Typhoon Morakot in 2009. The Laonung River watershed which covered 1367 km2 is selected as our study area. The study area is mainly compose of Miocene slate and sedimentary rocks that are separated by a major fault, the Meilungshan fault. The Meilungshan fault is part of the boundary fault separating the Central Range and Western Foothill in southern Taiwan. The fault is a west verging, high angle NNE trending thrust. Some outcrops show the fault zone is over one hundred and fifty meters thick, and it is mainly composed of gouge and fault breccias of slate. Within the study area, 361 sites with an area greater than 10 ha and with sliding topographic features of deep seated landslide such as crown main escarpment, down slope scarp, up slope scarps, and lateral cracks are recognized from LiDAR derived 1 m resolution DEM. Among these, 16 sites are selected for field investigation and all of them are confirmed as deep seated landslides. This implies the reliability of interpretation results from LiDAR derived DEM even in heavy forest region such as Taiwan. In order to know the influence of the Meilungshan fault in the development of deep seated landslides, landslide density are calculated. The landslide density is 7.7% when whole watershed is considered. However, the landslide density significantly increases to 19.3% when only an area 223km2 that contains the Meilungshan fault with a 2km buffer zone is in the calculation. This result indicates that deformation zone associated with major fault is crucial in the development of deep seated landslides in the study area.

  18. Habitat preferences of foraging red-cockaded woodpeckers at the Savannah River Site, South Carolina.

    SciTech Connect

    Franzreb, Kathleen, E.

    2004-12-31

    Franzreb, Kathleen, E. 2004. Habitat preferences of foraging red-cockaded woodpeckers at the Savannah River Site, South Carolina. In: Red-cockaded woodpecker; Road to Recovery. Proceedings of the 4th Red-cockaded woodpecker Symposium. Ralph Costa and Susan J. Daniels, eds. Savannah, Georgia. January, 2003. Chapter 9. Habitat Management and Habitat Relationships. Pp 553-561. Abstract: I constructed a foraging study to examine habitat use of red-cockaded woodpeckers at the Savannah River Site, South Carolina. Because much of the land had been harvested in the late 1940s and early 1950s prior to being sold to the Department of Energy, the available habitat largely consisted of younger trees (e.g., less than 40 years old). From 1992 to 1995, I examined the foraging behavior and reproductive success of 7 groups of red-cockaded woodpeckers.

  19. River Gain and Loss Studies for the Red River of the North Basin, North Dakota and Minnesota

    USGS Publications Warehouse

    Williams-Sether, Tara

    2004-01-01

    The Dakota Water Resources Act passed by the U.S. Congress in 2000 authorized the Secretary of the Interior to conduct a comprehensive study of future water-quantity and -quality needs of the Red River of the North (Red River) Basin in North Dakota and of possible options to meet those water needs. To obtain the river gain and loss information needed to properly account for available streamflow within the basin, available river gain and loss studies for the Sheyenne, Turtle, Forest, and Park Rivers in North Dakota and the Wild Rice, Sand Hill, Clearwater, South Branch Buffalo, and Otter Tail Rivers in Minnesota were reviewed. Ground-water discharges for the Sheyenne River in a reach between Lisbon and Kindred, N. Dak., were about 28.8 cubic feet per second in 1963 and about 45.0 cubic feet per second in 1986. Estimated monthly net evaporation losses for additional flows to the Sheyenne River from the Missouri River ranged from 1.4 cubic feet per second in 1963 to 51.0 cubic feet per second in 1976. Maximum water losses for a reach between Harvey and West Fargo, N. Dak., for 1956-96 ranged from about 161 cubic feet per second for 1976 to about 248 cubic feet per second for 1977. Streamflow gains of 1 to 1.5 cubic feet per second per mile were estimated for the Wild Rice, Sand Hill, and Clearwater Rivers in Minnesota. The average ground-water discharge for a 5.2-mile reach of the Otter Tail River in Minnesota was about 14.1 cubic feet per second in August 1994. The same reach lost about 14.1 cubic feet per second between February 1994 and June 1994 and about 21.2 cubic feet per second between August 1994 and August 1995.

  20. High resolution seismic survey, Pen Branch Fault, Savannah River Site, South Carolina

    SciTech Connect

    Berkman, E. )

    1991-04-01

    An investigation of the Pen Branch Fault at the Savannah River Site by a series of short, high resolution seismic reflection lines was conducted. The purpose was to acquire, process, and interpret 19.9 miles of data, optimized for the upper 300 ft of geologic strata, in sufficient density such that processing performed in the conventional stepwise approach, followed by detailed interpretation, would define small scale spatial variability and structural features in the vicinity of the fault leading to definition of the location of the fault, the shallowest extent of the fault, and the quantification of the sense and magnitude of motion. The depth of optimization for the last two lines was modified to the 300 ft of geologic strata immediately above basement. Three older seismic surveys, other geophysical data, and associated borehole and geologic data were reviewed. The equipment and the acquisition, processing, and interpretation procedures are discussed in the report. The report includes a detailed line by line description and discussion of the interpretation. Figures include reference maps, contour displays of the stacking and interval velocities, diagrammatic references sketches of the interpreted layering and sedimentary features, index sketches, and specific color prints made on the workstation during the course of the interpretation. A volume of manuals on seismic devices and related equipment is included.

  1. High resolution seismic survey, Pen Branch Fault, Savannah River Site, South Carolina. Final report

    SciTech Connect

    Berkman, E.

    1991-04-01

    An investigation of the Pen Branch Fault at the Savannah River Site by a series of short, high resolution seismic reflection lines was conducted. The purpose was to acquire, process, and interpret 19.9 miles of data, optimized for the upper 300 ft of geologic strata, in sufficient density such that processing performed in the conventional stepwise approach, followed by detailed interpretation, would define small scale spatial variability and structural features in the vicinity of the fault leading to definition of the location of the fault, the shallowest extent of the fault, and the quantification of the sense and magnitude of motion. The depth of optimization for the last two lines was modified to the 300 ft of geologic strata immediately above basement. Three older seismic surveys, other geophysical data, and associated borehole and geologic data were reviewed. The equipment and the acquisition, processing, and interpretation procedures are discussed in the report. The report includes a detailed line by line description and discussion of the interpretation. Figures include reference maps, contour displays of the stacking and interval velocities, diagrammatic references sketches of the interpreted layering and sedimentary features, index sketches, and specific color prints made on the workstation during the course of the interpretation. A volume of manuals on seismic devices and related equipment is included.

  2. [Temporal and spatial distribution of red tide in Yangtze River Estuary and adjacent waters].

    PubMed

    Liu, Lu-San; Li, Zi-Cheng; Zhou, Juan; Zheng, Bing-Hui; Tang, Jing-Liang

    2011-09-01

    The events of red tide were collected in Yangtze River Estuary and adjacent waters from 1972 to 2009. Based on geographic information system (GIS) analysis on the temporal and spatial distribution of red tide, the distribution map was generated accordingly. The results show: (1) There are three red tide-prone areas, which are outside the Yangtze River estuary and the eastern of Sheshan, Huaniaoshan-Shengshan-Gouqi, Zhoushan and the eastern of Zhujiajian. The red tide occurred 174 times in total, in which there were 25 times covered the area was larger than 1 000 km2. After 2000, the frequency of red tide were significantly increasing; (2) The frequent occurrence of red tide was in May (51% of total occurrence) and June (20% of total occurrence); (3) In all of the red tide plankton, the dominant species were Prorocentrum danghaiense, Skeletonema costatum, Prorocentrum dantatum, Nactiluca scientillans. The red tides caused by these species were 38, 35, 15, 10 times separately. PMID:22165212

  3. The Mint River Fault: an Extensional Detachment in the York Mountains, Seward Peninsula, Alaska

    NASA Astrophysics Data System (ADS)

    Toro, J.; Burnette, L.; Amato, J.; Repetski, J.; Gehrels, G.

    2005-12-01

    The role of crustal extension in the origin of the gneiss domes of the Bering Strait region of Alaska and Russia has been debated for over a decade. Alternative models for gneiss dome formation include 1) thermal re-equilibration after crustal thickening by arc collision (Lieberman, 1988; Patrick and Evans, 1989); 2) extensional collapse of the crust during with mid-Cretaceous magmatism (Miller et al., 1992; Amato et al., 1994) and 3) thermally-induced diapiric rise of the high-grade rocks (Calvert et al., 1999). One major difference with the classic metamorphic core complexes of the Basin and Range is that, because of deep exhumation, evidence for mid-Cretaceous supra-crustal extension has not been widely documented in the Bering Strait region. In the York Mountains, the one area of the Seward Peninsula where unmetamorphosed rocks are preserved, the structure was originally described as a thrust belt (Sainsbury, 1969). New detailed mapping, structural analysis, 40Ar/39Ar thermochronology, and conodont biostratigraphy carried out in the York Mountains show that the Mint River Fault, which is the basal detachment of the supposed thrust belt, is actually a low angle extensional detachment fault. This fault separates polydeformed low greenschist grade rocks in the lower plate from unmetamorphosed Lower Ordovician to Silurian carbonates in the upper plate. The upper plate is cut by three major normal faults, the largest of which has about 4 km of down-to-the-south slip. These faults also tilt the Early Paleozoic carbonate succession. A younger-on-older relationship across one of the mayor faults is documented by conodont biostratigraphy demonstrating that these are not thrusts, as was previously believed. Stress inversion, based on minor brittle faults in the upper plate, indicates a direction of extension of 194, which is consistent with the strike of major normal faults. No direct evidence of bedding-plane thrusting could be documented, although minor folds do exist, probably formed during shortening that predated extensional deformation. The lower plate is composed of latest Proterozoic to early Cambrian lithic quartzites and slates intruded by 540+/-5 Ma gabbros (LA-ICPMS U/Pb in zircon), overlain by Lower Ordovician metacarbonates. The structure of the lower plate is characterized by at least two generations of folds. The kinematics of the earliest event are obscure, as the F1 fold axes are widely scattered and fold vergence is inconsistent. The D2 event resulted in vertical flattening and the dominant sub-horizontal metamorphic fabric. Lower plate slates yielded disturbed 40Ar/39Ar spectra with predominantly mid-Jurassic to mid-Cretaceous age steps. Although the quality of these data does not allow unambiguous interpretation, it does suggest that greenschist facies metamorphism took place in the Late Mesozoic. Extensional deformation must have occurred after metamorphism and prior to intrusion of the Brooks Mountain granite, which cuts the Mint River Fault, and is dated at 77.8+/-1 Ma by 40Ar/39Ar in biotite. Basaltic dikes in the upper plate, which are subparallel to the mayor normal faults, yielded 40Ar/39Ar ages of 77 to 78 Ma. Although the timing of the onset of extension in the York Mountains is poorly constrained so far, it appears to be compatible with the rise of the Kigluiak dome, which culminated at about 90 Ma (Amato et al., 2001).

  4. Protect and Restore Red River Watershed, 2007-2008 Annual Report.

    SciTech Connect

    Bransford, Stephanie

    2009-05-04

    The Nez Perce Tribe Department of Fisheries Resource Management, Watershed Division approaches watershed restoration with a ridge-top to ridge-top approach. The Nez Perce Tribe (NPT) and the Nez Perce National Forest (NPNF) have formed a partnership in completing watershed restoration activities, and through this partnership more work is accomplished by sharing funding and resources in our effort. The Nez Perce Tribe began watershed restoration projects within the Red River Watershed of the South Fork Clearwater River in 2001. Progress has been made in restoring the watershed through road decommissioning and culvert replacement. From completing a watershed assessment to two NEPA efforts and a final stream restoration design, we will begin the effort of restoring the mainstem channel of Red River to provide spawning and rearing habitat for anadromous and resident fish species. Roads have been surveyed and prioritized for removal or improvement as well as culverts being prioritized for replacement to accommodate fish passage throughout the watershed. Another major, and extremely, important component of this project is the Red River Meadow Conservation Easement. We have begun the process of pursuing a conservation easement on approximately 270 acres of prime meadow habitat (Red River runs through this meadow and is prime spawning and rearing habitat).

  5. 78 FR 76596 - Proposed Levels of Service at Locks and Dams on the J Bennett Johnston Waterway (Red River)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-18

    ..., 2013 (78 FR 34083). The hours of availability for locking at Lindy C. Boggs Lock and Dam, John H... Johnston Waterway (Red River) AGENCY: Department of the Army, U.S. Army Corps of Engineers, DoD. ACTION... regulation governing the use, administration, and navigation of the Red River and Locks is Section 4 of...

  6. 77 FR 47493 - DMH Trust fbo Martha M. Head-Acquisition of Control Exemption-Red River Valley & Western Railroad...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-08

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF TRANSPORTATION Surface Transportation Board DMH Trust fbo Martha M. Head--Acquisition of Control Exemption-- Red River..., has filed a verified notice of exemption to acquire control of Red River Valley & Western...

  7. Distributions of median nutrient and chlorophyll concentrations across the Red River Basin, USA.

    PubMed

    Longing, D; Haggard, B E

    2010-01-01

    Acquisition and compilation of water-quality data for an 11-yr time period (1996-2006) from 589 stream and river stations were conducted to support nutrient criteria development for the multistate Red River Basin shared by Arkansas, Louisiana, New Mexico, Oklahoma, and Texas. Ten water-quality parameters were collected from six data sources (USGS, Arkansas Department of Environmental Quality, Louisiana Department of Environmental Quality, Oklahoma Conservation Commission, Oklahoma Water Resources Board, and Texas Commission on Environmental Quality), and an additional 13 parameters were acquired from at least one source. Median concentrations of water-quality parameters were calculated at each individual station and frequency distributions (minimum, 10th, 25th, 50th, 75th, 90th percentiles, and maximum) of the median concentrations were calculated. Across the Red River Basin, median values for total nitrogen (TN), total phosphorus (TP), and sestonic chlorophyll-a (chl-a) ranged from < 0.02 to 20.2 mg L(-1), < 0.01 to 6.66 mg L(-1), and 0.10 to 262 microg L(-1), respectively. Overall, the 25th percentiles of TN data specific to the Red River Basin were generally similar to the USEPA-recommended ecoregion nutrient criteria of 0.31 to 0.88 mg L(-1), whereas median TP and chl-a data specific to the Red River Basin showed 25th percentiles higher than the USEPA-recommended criteria (0.010-0.067 mg TP L(-1); 0.93-3.00 microg chl-a L(-1)). The unique location of the Red River Basin in the south-central United States places it near the boundaries of several aggregate ecoregions; therefore, the development of ecoregion nutrient criteria likely requires using data specific to the Red River Basin, as shown in these analyses. This study provided basin-specific frequency distribution of median concentrations of water-quality parameters as the first step to support states in developing nutrient criteria to protect designated uses in the multijurisdictional Red River Basin. PMID:21284293

  8. RED SHINER INVASION OF THE UPPER COOSA RIVER SYSTEM: DYNAMICS AND ECOLOGICAL CONSEQUENCES

    EPA Science Inventory

    The red shiner (Cyprinella lutrensis) has been widely introduced across 11 states outside its native range, presumably through bait-bucket and aquarium releases. Its native range includes Great Plain and Central Lowland tributaries of the Mississippi River and western Coastal Pla...

  9. 77 FR 47334 - Safety Zone; Red Bull Flugtag, Delaware River; Camden, NJ

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-08

    ... Acronyms DHS Department of Homeland Security FR Federal Register NPRM Notice of Proposed Rulemaking A... Federal Register (73 FR 3316). 4. Public Meeting We do not now plan to hold a public meeting. But you may... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Red Bull Flugtag, Delaware River;...

  10. Floods in a Changing Climate: A Case Study From the Red River Basin

    NASA Astrophysics Data System (ADS)

    Rasmussen, P. F.

    2014-12-01

    In many parts of the world, the frequency of large flood events appears to have increased. Although it is impossible to associate any particular event with climate change, there is a general perception that climate change may be at least part of the reason for changes in the statistical distribution of floods. The Red River, sometimes called the Red River of the North, originates at the borders of North Dakota, South Dakota, and Minnesota and flows north through the Province of Manitoba before emptying into Lake Winnipeg. There have been several severe spring floods on the Red River in recent years, creating speculation that increased greenhouse gas concentrations are changing the frequency of floods. In this study, we investigate whether this is a reasonable assumption based on global climate model output. A regression model has been developed to predict spring peak discharge on the Red River at a streamflow gage located at the border of the US and Canada. The predictor variables include antecedent fall precipitation used as a proxy for soil moisture at freeze-up, winter snow accumulation, and spring precipitation during the period of melt. Data from the CMIP5 GCM model ensemble are used to determine change factors for the predictor variables. The modified predictor variables are then used to produce scenarios of floods in a changed climate. The use of multiple GCMs and multiple Representative Concentration Pathways (RCPs) allows for an estimate of uncertainty to be associated with the results.

  11. Application of an inverse method for calculating three-dimensional fault geometries and clip vectors, Nun River Field, Nigeria

    SciTech Connect

    Kerr, H.G.; White, N.

    1996-03-01

    A general, automatic method for determining the three-dimensional geometry of a normal fault of any shape and size is applied to a three-dimensional seismic reflection data set from the Nun River field, Nigeria. In addition to calculating fault geometry, the method also automatically retrieves the extension direction without requiring any previous information about either the fault shape or the extension direction. Solutions are found by minimizing the misfit between sets of faults that are calculated from the observed geometries of two or more hanging-wall beds. In the example discussed here, the predicted fault surface is in excellent agreement with the shape of the seismically imaged fault. Although the calculated extension direction is oblique to the average strike of the fault, the value of this parameter is not well resolved. Our approach differs markedly from standard section-balancing models in two important ways. First, we do not assume that the extension direction is known, and second, the use of inverse theory ensures that formal confidence bounds can be determined for calculated fault geometries. This ability has important implications for a range of geological problems encountered at both exploration and production scales. In particular, once the three-dimensional displacement field has been constrained, the difficult but important problem of three-dimensional palinspastic restoration of hanging-wall structures becomes tractable.

  12. Preconstruction and postconstruction ground-water levels, Lock and Dam 2, Red River Valley, Louisiana

    USGS Publications Warehouse

    Ludwig, A.H.

    1979-01-01

    Proposed construction of a series of locks and dams in the Red River in Louisiana will cause a permanent increase in average river stage. The potentiometric surface of the shallow alluvial aquifer and the water table in the fine-grained material confining the aquifer will be affected. The purpose of this study, using digital-modeling techniques, was to predict the average postconstruction potentiometric surface (steady state) and the water table (nonsteady state) so that potential effects of the water-level changes could be evaluated. Plans for lock and dam 1 at mile 44 (kilometer 71) above the mouth of the Red River call for a pool elevation of 40 feet (12.2 meters) and will cause an average increase in river stage of 9 feet (2.7 meters). As a result, ground-water levels will be raised 1 foot (0.3 meter) or more within 4 miles (6.4 kilometers) of the river. The potentiometric surface may be near land surface in low-lying areas, and above land surface along the course of drainage features near the dam. The magnitude of ground-water-level fluctuations near the river will be reduced. (Woodard-USGS)

  13. Preconstruction and postconstruction ground-water levels, Lock and Dam 3, Red River Valley, Louisiana

    USGS Publications Warehouse

    Ludwig, A.H.; Terry, J.E.

    1979-01-01

    Proposed construction of a series of locks and dams in the Red River in Louisiana will cause a permanent increase in average river stage. The potentiometric surface of the shallow alluvial aquifer and the water table in the fine-grained material confining the aquifer will be affected. The purpose of this study, using digital-modeling techniques, was to predict the average postconstruction potentiometric surface (steady state) and the water table (nonsteady state) so that potential effects of the water-level changes could be evaluated. Plans for lock and dam 3 at realined mile 111 (kilometer 179) above the mouth of the Red River call for a pool elevation of 87 feet (27 meters) and will cause an average increase in river stage ranging from 21 to 3.5 feet (l.4 to 1.1 meters). As a result, ground-water levels will be raised to near land surface in low areas east of the river from the damsite to Aloha and in a 0.5-mile (0.8-kilometer) strip along the west side extending 9 miles (14 kilometers) above the dam. The potentiometric surface may be above land surface locally near the dam. The magnitude of ground-water-level fluctuations near the river will be reduced to less than half the preconstruction range.

  14. Preconstruction and postconstruction ground-water levels, Lock and Dam 2, Red River Valley, Louisiana

    USGS Publications Warehouse

    Ludwig, A.H.

    1979-01-01

    Proposed construction of a series of locks and dams in the Red River in Louisiana will cause a permanent increase in average river stage. The potentiometric surface of the shallow alluvial aquifer and the water table in the fine-grained material confining the aquifer will be affected. The purpose of this study using digital-modeling techniques, was to predict the average postconstruction potentiometric surface (steady state) and the water table (nonsteady state) so that potential effects of the water-level changes could be evaluated. Plans for lock and dam 2 at mile 87 (kilometer 140) above the mouth of the Red River call for a pool elevation of 58 feet (17.7 meters) and will cause an average increase in river stage of 12.5 feet (3.8 meters). As a result, ground-water levels will be raised 1 foot (0.3 meter) or more within 4 miles (6.4 kilometers) of the river and will be near land surface in low areas. The potentiometric surface may be as much as 1 to 2 feet (0.3 to 0.6 meter) above land surface south of Latanier along Chatlin Lake Canal and south of the Annandale area of Alexandria. The magnitude of ground-water-level fluctuations near the river will be reduced.

  15. Preconstruction and simulated postconstruction ground-water levels at urban centers in the Red River Navigation Project area, Louisiana

    USGS Publications Warehouse

    Rogers, J.E.

    1984-01-01

    The Red River Valley in Louisiana is 3 to 10 miles wide and is underlain by the Red River alluvial aquifer. This aquifer is in hydraulic connection with the Red River. Precipitation infiltrates the aquifer and water discharges from the aquifer at the Red River and major tributaries. Construction of locks and dams along the Red River will cause new, higher minimum stages for the river for each of the pools. Water levels will rise and outflow from the alluvial aquifer to the river after construction of the locks and dams will be at higher elevations because of the new river stages. Mathematical models of the stream-aquifer system simulate the effects of the lock and dam system for plan B-3, modified. Water-level changes in the aquifer in response to the changes imposed by the system are greatest near the river and are progressively smaller away from the river. The saturated zone in the fine-grained material overlying the aquifer provides the principal potential impact on structures and vegetation in urban areas. As water levels in the aquifer rise, the saturated zone above the aquifer will decrease the thickness. The soil zone in low areas in some communities will be waterlogged. (USGS)

  16. Red shiner invasion and hybridization with blacktail shiner in the upper Coosa River, USA

    USGS Publications Warehouse

    Walters, D.M.; Blum, M.J.; Rashleigh, B.; Freeman, B.J.; Porter, B.A.; Burkhead, N.M.

    2008-01-01

    Human disturbance increases the invasibility of lotic ecosystems and the likelihood of hybridization between invasive and native species. We investigated whether disturbance contributed to the invasion of red shiner (Cyprinella lutrensis) and their hybridization with native blacktail shiner (C. venusta stigmatura) in the Upper Coosa River System (UCRS). Historical records indicated that red shiners and hybrids rapidly dispersed in the UCRS via large, mainstem rivers since the mid to late 1990s. We measured the occurrence and abundance of parental species and hybrids near tributary-mainstem confluences and characterized populations at these incipient contact zones by examining variation across morphological traits and molecular markers. Red shiners represented only 1.2% of total catch in tributaries yet introgression was widespread with hybrids accounting for 34% of total catch. Occurrence of red shiners and hybrids was highly correlated with occurrence of blacktail shiners, indicating that streams with native populations are preferentially colonized early in the invasion and that hybridization is a key process in the establishment of red shiners and their genome in new habitats. Tributary invasion was driven by post-F1 hybrids with proportionately greater genomic contributions from blacktail shiner. Occurrence of red shiners and hybrids and the relative abundance of hybrids significantly increased with measures of human disturbance including turbidity, catchment agricultural land use, and low dissolved oxygen concentration. Red shiners are a significant threat to Southeast Cyprinella diversity, given that 41% of these species hybridize with red shiner, that five southeastern drainages are invaded, and that these drainages are increasingly disturbed by urbanization. ?? 2007 Springer Science+Business Media B.V.

  17. A comprehensive fluvial geomorphology study of riverbank erosion on the Red River in Winnipeg, Manitoba, Canada

    NASA Astrophysics Data System (ADS)

    Kimiaghalam, Navid; Goharrokhi, Masoud; Clark, Shawn P.; Ahmari, Habib

    2015-10-01

    Riverbank erosion on the Red River in Winnipeg, Manitoba has raised concerns over the last 20 years and more. Although several recent studies have shown that fluvial erosion can reduce riverbank stability and promote geotechnical slope failure, there are too few that have focused on this phenomenon. The present study includes field measurements, experimental testing, and numerical modelling to quantify fluvial erosion through a 10 km reach of the Red River. Results have shown that seasonal freeze-thaw processes can dramatically reduce the critical shear stress and increase erodibility of the riverbanks. Moreover, a simple method has been employed using hydrodynamic numerical models to define the applied shear stresses on the river banks based on the river water level, which will be useful for further research and design purposes. The TEMP/W numerical model was used to define seasonal frost depth to estimate freeze-thaw effects. Finally all field measurements, experimental and numerical models results were used to predict annual fluvial erosion through this reach of the river.

  18. Water type and suitability of Oklahoma surface waters for public supply and irrigation Part 4: Red River mainstem and North Fork Red River basin through 1979

    USGS Publications Warehouse

    Stoner, Jerry D.

    1981-01-01

    Water-quality data for the Red River mainstem and the North Fork Red River basin within Oklahoma, through 1979, were examined for water type and suitability for public water supply and irrigation use. Of 96 stations with available data, 53 stations or 55 percent were considered to have sufficient data for analysis. The classification of water type was based on the relation of the major ions: calcium, magnesium, sodium, carbonate, bicarbonate, sulfate, and chloride to each other within the range of measured specific conductance. The suitability of the water for use as a public supply was based on the concentration distribution of selected constituents. The constituents selected were those with maximum contaminant levels established by regulation, or constituents for which recommended maximum limits have been established and for which historic data are available. The irrigation-classification method of Wilcox was used to relate sodium, calcium, and magnesium concentrations and the salinity distribution to the use of the water for irrigation. If data are available, the chance of phytotoxic effects by boron is discussed.

  19. Bathymetry of the Hong and Luoc River Junction, Red River Delta, Vietnam, 2010

    USGS Publications Warehouse

    Kinzel, Paul J.; Nelson, Jonathan M.; Toan, Duong Duc; Thanh, Mung Dinh; Shimizu, Yasuyuki

    2012-01-01

    The U.S. Geological Survey, in collaboration with the Water Resources University in Hanoi, Vietnam, conducted a bathymetric survey of the junction of the Hong and Luoc Rivers. The survey was done to characterize the channel morphology of this delta distributary network and provide input for hydrodynamic and sediment transport models. The survey was carried out in December 2010 using a boat-mounted multibeam echo sounder integrated with a global positioning system. A bathymetric map of the Hong and Luoc River junction was produced which was referenced to the datum of the Trieu Duong tide gage on the Luoc River.

  20. INTELLIGENT COMPUTING SYSTEM FOR RESERVOIR ANALYSIS AND RISK ASSESSMENT OF THE RED RIVER FORMATION

    SciTech Connect

    Mark A. Sippel; William C. Carrigan; Kenneth D. Luff; Lyn Canter

    2003-11-12

    Integrated software has been written that comprises the tool kit for the Intelligent Computing System (ICS). The software tools in ICS have been developed for characterization of reservoir properties and evaluation of hydrocarbon potential using a combination of inter-disciplinary data sources such as geophysical, geologic and engineering variables. The ICS tools provide a means for logical and consistent reservoir characterization and oil reserve estimates. The tools can be broadly characterized as (1) clustering tools, (2) neural solvers, (3) multiple-linear regression, (4) entrapment-potential calculator and (5) file utility tools. ICS tools are extremely flexible in their approach and use, and applicable to most geologic settings. The tools are primarily designed to correlate relationships between seismic information and engineering and geologic data obtained from wells, and to convert or translate seismic information into engineering and geologic terms or units. It is also possible to apply ICS in a simple framework that may include reservoir characterization using only engineering, seismic, or geologic data in the analysis. ICS tools were developed and tested using geophysical, geologic and engineering data obtained from an exploitation and development project involving the Red River Formation in Bowman County, North Dakota and Harding County, South Dakota. Data obtained from 3D seismic surveys, and 2D seismic lines encompassing nine prospective field areas were used in the analysis. The geologic setting of the Red River Formation in Bowman and Harding counties is that of a shallow-shelf, carbonate system. Present-day depth of the Red River formation is approximately 8000 to 10,000 ft below ground surface. This report summarizes production results from well demonstration activity, results of reservoir characterization of the Red River Formation at demonstration sites, descriptions of ICS tools and strategies for their application.

  1. Spatial/temporal patterns of Quaternary faulting in the southern limb of the Yellowstone-Snake River Plain seismic parabola, northeastern Basin and Range margin

    SciTech Connect

    McCalpin, J.P. )

    1993-04-01

    During the period 1986--1991, 11 backhoe trenches were excavated across six Quaternary faults on the northeastern margin of the Basin and Range province. These faults comprise the southern limb of a parabola of Quaternary faults and historic moderate-magnitude earthquakes which is roughly symmetrical about the Snake River Plain, and heads at the Yellowstone hot spot. Fifteen Holocene paleoseismic events have been bracketed by radiocarbon or thermoluminescence ages. On the six central faults, the latest rupture event occurred in a relatively short time interval between 3 ka and 6 ka. The period between 6 ka and the end of the latest glaciation (ca. 15 ka) was a period of relative tectonic quiescence on the central faults, but not on the two end faults with higher slip rates (Wasatch and Teton faults). Southward-younging of events in the 3--6 ka period may indicate that temporally-clustered faulting was initiated at the Yellowstone hot spot. Faults at the same latitude, such as the Star Valley-Grey's River pair of faults, or the East Cache-Bear Lake-Rock Creek system of faults, show nearly identical timing of latest rupture events within the pairs or systems. Faults at common latitudes probably sole into the same master decollement, and thus are linked mechanically like dominoes. The timing of latest ruptures indicates that faulting on the westernmost fault preceded faulting on successively more eastern faults by a few hundred years. This timing suggests that slip on the westernmost faults mechanically unloaded the system, causing tectonic instabilities farther east.

  2. Establishment of a viable population of red-cockaded woodpeckers at the Savannah River Site

    SciTech Connect

    Allen, D.H.

    1989-01-01

    In 1985 the Southeastern Forest Experiment Station in cooperation with the Department of Energy (DOE), the Savannah River Forest Station (SRFS) and the Savannah River Ecology Laboratory (SREL) initiated a research/management program to restore a viable population of red-cockaded woodpeckers (RCW) to the Savannah River Site (SRS). The program has progresses in two phases. The first phase (1985-1987) focused on stabilizing the declining RCW population at SRS. The second phase (1988-present) has focused on facilitating population expansion. In 1989 we have focused our efforts on development of techniques for excavating new RCW cavities, identification of old-growth stands with the potential of providing new nesting habitat to support population expansion, continued flying squirrel control, continued translocations of RCW's as needed, and monitoring clan composition and reproduction.

  3. Topography, river network and recent fault activity at the margins of the Central Main Ethiopian Rift (East Africa)

    NASA Astrophysics Data System (ADS)

    Molin, Paola; Corti, Giacomo

    2015-11-01

    Along its length, the Main Ethiopian Rift (MER) in East Africa records a transition from early fault-dominated morphology in the South to axial magma assisted-rifting typical of continental break-up in the North. It is one of the few locations on Earth offering a complete picture of the evolution of continental rifting and thus provides a unique opportunity to directly analyze how the drainage network reorganizes under extensional tectonic forcing. In this paper we present a new analysis of the river network and relative landforms-complemented with a summary of recent geological data-at both rift margins of the Central MER, a key sector of the rift capturing the phase of drainage reorganization between incipient and mature rifting. This analysis shows that hydrography is strongly influenced by recent tectonics. Rectangular drainage patterns, windgaps, and lacustrine/swampy areas formed by structural dams document that the rivers are in continuous competition with fault activity. The irregular longitudinal profiles (with knickpoints/knickzones in correspondence with faults) also suggest that rivers are in a transient state of disequilibrium related to recent tectonic activity at rift margins, in agreement with previous geological and seismological data. A more regional analysis extended to the adjoining Northern and Southern MER indicates that rifting evolves from initial stages characterized by margins poorly incised by rivers with gentle channel gradients (except in correspondence with faults), to mature phases in which rift margins are highly incised by a well organized fluvial network composed by concave and steep rivers. Our regional analysis also indicates a stronger and/or more recent tectonic activity at the rift margins proceeding to the south, in line with previous models of rift development.

  4. Effects of Late Cretaceous and Cenozoic faulting on the geology and hydrology of the coastal plain near the Savannah River, Georgia and South Carolina

    USGS Publications Warehouse

    Faye, R.E.; Prowell, D.C.

    1982-01-01

    Geologic and hydrologic investigations by the U.S. Geological Survey have defined stratigraphic and hydraulic anomalies suggestive of faulting within Coastal Plain sediments between the Ogeechee River in east-central Georgia and the Edisto River in west-central South Carolina. Examination of borehole cuttings, cores, and geophysical logs from test wells indicate that Triassic rocks and Upper Cretaceous and lower Tertiary Coastal Plain sediments near the Barnwell-Allendale County line near Millett, South Carolina, are offset by a northeast-trending fault downthrown to the northwest. The location of this suspected Coastal Plain fault generally coincides with the location of an inferred fault in basement rocks as interpreted from aeromagnetic surveys. Apparent vertical offsets range from about 700 feet at the base of Upper Cretaceous sediments to about 20 feet in strata of Late Eocene age. As a result, the Upper Cretaceous Middendorf Formation which directly overlies crystalline and Triassic rocks updip (northwest) of this fault, is absent immediately downdip of the fault. The thickness of Tipper Cretaceous sediments is also sharply reduced from about 700 feet to about 180 feet across the fault. Sediments of the basal Coastal Plain aquifer are largely truncated by uplifted Triassic rocks at the fault near Millett, South Carolina. Lateral ground-water flow near the Savannah River Is consequently disrupted updip of the fault and ground water is transferred vertically into overlying sediments and possibly into the Savannah River. At several locations, abrupt changes in potentiometric head occur across this fault. Computed transmissivity of the basal Coastal Plain aquifer is also radically reduced downdip of the fault, sharply reversing a downdip trend of rapidly increasing aquifer transmissivity. Other anomalous potentiometric data along a northeast-trending line between Statesboro, Georgia, and Fairfax, South Carolina, suggest the possibility of similar faulting in correlative geologic units. The location of the suspected fault near Statesboro, Georgia, generally coincides with the eastward extension of the Gulf Trough, a regional potentiometric anomaly in central Georgia.

  5. Forecasting changes in water quality in rivers associated with growing biofuels in the Arkansas-White-Red river basin, USA

    DOE PAGESBeta

    Jager, Yetta; Brandt, Craig C; Baskaran, Latha Malar; Srinivasan, Raghavan; Turhollow Jr, Anthony F; Schweizer, Peter E

    2015-01-01

    The mid-section of the Arkansas-White-Red (AWR) river basin near the 100th parallel is particularly promising for sustainable biomass production using cellulosic perennial crops and residues. Along this longitudinal band, precipitation becomes limiting to competing crops that require irrigation from an increasingly depleted groundwater aquifer. In addition, the deep-rooted perennial, switchgrass, produces modest-to-high yields in this region with minimal inputs and could compete against alternative crops and land uses at relatively low cost. Previous studies have also suggested that switchgrass and other perennial feedstocks offer environmentally benign alternatives to corn and corn stover. However, water quality implications remain a significant concernmore » for conversion of marginal lands to bioenergy production because excess nutrients produced by agriculture for food or for energy contribute to eutrophication in the dead-zone in the Gulf of Mexico. This study addresses water quality implications for the AWR river basin. We used the SWAT model to compare water quality in rivers draining a baseline, pre-cellulosic-bioenergy and post-cellulosic-bioenergy landscapes for 2022 and 2030. Simulated water quality responses varied across the region, but with a net tendency toward decreased amounts of nutrient and sediment, particularly in subbasins with large areas of bioenergy crops in 2030 future scenarios. We conclude that water quality is one aspect of sustainability for which cellulosic bioenergy production in this region holds promise.« less

  6. Forecasting changes in water quality in rivers associated with growing biofuels in the Arkansas-White-Red river drainage, USA

    DOE PAGESBeta

    Jager, Henriette I.; Baskaran, Latha M.; Schweizer, Peter E.; Turhollow, Anthony F.; Brandt, Craig C.; Srinivasan, Raghavan

    2014-05-15

    We study that the mid-section of the Arkansas-White-Red (AWR) river basin near the 100th parallel is particularly promising for sustainable biomass production using cellulosic perennial crops and residues. Along this longitudinal band, precipitation becomes limiting to competing crops that require irrigation from an increasingly depleted groundwater aquifer. In addition, the deep-rooted perennial, switchgrass, produces modest-to-high yields in this region with minimal inputs and could compete against alternative crops and land uses at relatively low cost. Previous studies have also suggested that switchgrass and other perennial feedstocks offer environmentally benign alternatives to corn and corn stover. However, water quality implications remainmore » a significant concern for conversion of marginal lands to bioenergy production because excess nutrients produced by agriculture for food or for energy contribute to eutrophication in the dead-zone in the Gulf of Mexico. This study addresses water quality implications for the AWR river basin. We used the SWAT model to compare water quality in rivers draining a baseline, pre-cellulosic-bioenergy and post-cellulosic-bioenergy landscapes for 2022 and 2030. Simulated water quality responses varied across the region, but with a net tendency toward decreased amounts of nutrient and sediment, particularly in subbasins with large areas of bioenergy crops in 2030 future scenarios. We conclude that water quality is one aspect of sustainability for which cellulosic bioenergy production in this region holds promise.« less

  7. Forecasting changes in water quality in rivers associated with growing biofuels in the Arkansas-White-Red river drainage, USA

    SciTech Connect

    Jager, Henriette I.; Baskaran, Latha M.; Schweizer, Peter E.; Turhollow, Anthony F.; Brandt, Craig C.; Srinivasan, Raghavan

    2014-05-15

    We study that the mid-section of the Arkansas-White-Red (AWR) river basin near the 100th parallel is particularly promising for sustainable biomass production using cellulosic perennial crops and residues. Along this longitudinal band, precipitation becomes limiting to competing crops that require irrigation from an increasingly depleted groundwater aquifer. In addition, the deep-rooted perennial, switchgrass, produces modest-to-high yields in this region with minimal inputs and could compete against alternative crops and land uses at relatively low cost. Previous studies have also suggested that switchgrass and other perennial feedstocks offer environmentally benign alternatives to corn and corn stover. However, water quality implications remain a significant concern for conversion of marginal lands to bioenergy production because excess nutrients produced by agriculture for food or for energy contribute to eutrophication in the dead-zone in the Gulf of Mexico. This study addresses water quality implications for the AWR river basin. We used the SWAT model to compare water quality in rivers draining a baseline, pre-cellulosic-bioenergy and post-cellulosic-bioenergy landscapes for 2022 and 2030. Simulated water quality responses varied across the region, but with a net tendency toward decreased amounts of nutrient and sediment, particularly in subbasins with large areas of bioenergy crops in 2030 future scenarios. We conclude that water quality is one aspect of sustainability for which cellulosic bioenergy production in this region holds promise.

  8. Forecasting changes in water quality in rivers associated with growing biofuels in the Arkansas-White-Red river basin, USA

    SciTech Connect

    Jager, Yetta; Brandt, Craig C; Baskaran, Latha Malar; Srinivasan, Raghavan; Turhollow Jr, Anthony F; Schweizer, Peter E

    2015-01-01

    The mid-section of the Arkansas-White-Red (AWR) river basin near the 100th parallel is particularly promising for sustainable biomass production using cellulosic perennial crops and residues. Along this longitudinal band, precipitation becomes limiting to competing crops that require irrigation from an increasingly depleted groundwater aquifer. In addition, the deep-rooted perennial, switchgrass, produces modest-to-high yields in this region with minimal inputs and could compete against alternative crops and land uses at relatively low cost. Previous studies have also suggested that switchgrass and other perennial feedstocks offer environmentally benign alternatives to corn and corn stover. However, water quality implications remain a significant concern for conversion of marginal lands to bioenergy production because excess nutrients produced by agriculture for food or for energy contribute to eutrophication in the dead-zone in the Gulf of Mexico. This study addresses water quality implications for the AWR river basin. We used the SWAT model to compare water quality in rivers draining a baseline, pre-cellulosic-bioenergy and post-cellulosic-bioenergy landscapes for 2022 and 2030. Simulated water quality responses varied across the region, but with a net tendency toward decreased amounts of nutrient and sediment, particularly in subbasins with large areas of bioenergy crops in 2030 future scenarios. We conclude that water quality is one aspect of sustainability for which cellulosic bioenergy production in this region holds promise.

  9. Structure and geological history of the Lepanto-Cervantes releasing bend on the Abra river fault, Luzon Central Cordillera, Philippines

    NASA Astrophysics Data System (ADS)

    Ringenbach, Jean Claude; Stephan, Jean François; Maleterre, Philippe; Bellon, Herve

    1990-11-01

    The Luzon Central Cordillera corresponds to the uplifted and tectonized magmatic arc associated with the Manila Trench subduction zone. It is cut into N-S trending strips by the horsetail-like overprint of the Philippine strike-slip fault. The median branch, herein named the Abra River Fault, splits away to the west from the Dalton Fault and runs north-northwestward for 240 km through the range. Trending N150E in its southern part, it undergoes a sinistral bend in the Lepanto-Cervantes area, and then strikes N-S, makes a second bend and runs north-northeast up to the northwestern tip of the island. In the bend area, the compartment east of the fault has subsided, forming a narrow strip along the southern Lepanto segment and a wider trough parallel to the fault which stretches 25 km from Cervantes. The basement of the strip is position dependent, corresponding either to the Oligo-Miocene arc succession (volcanoclastic sediments and dioritic intrusive), or to the pre-Late Eocene ophiolitic basement of the arc. In the Lepanto area, two volcanic formations are preserved: the oldest one, the Malaya Formation is latest Miocene in age (6.1 ± 0.3 and 5.7 ± 0.28 Ma by K/Ar) and represents the infill of the trough, the youngest, the Mount Pudso volcanics, is Holocene in age (0.5 Ma by K/Ar). The Cervantes trough contains a thick (reaching 1700 m) volcanoclastic sequence dated as latest Miocene-Early Pliocene (3.7 ± 0.18-6.2 ± 0.28 Ma by K/Ar (the Malaya Formation). On the western and southern sides, the Abra River Fault separates the very deformed infill from the strongly uplifted pre-Late Miocene basement. On the east side, the basement, whose elevation increases gradually eastward, is disconformably overlain by the Mio-Pliocene sequence. To the north, the trough is slightly deformed. The structural analysis of the Lepanto-Cervantes strip, together with the local and regional geological and geochronological data, allow us to propose a three-stage history. The first stage during the early Late Miocene, is the major left-lateral wrench displacement of the Abra River Fault and the appearance of the bend under a transpressive regime. The second stage from latest Miocene to Early Pliocene, and marked by strong volcanic activity, comes with and/or immediately follows the subsidence of the Lepanto-Cervantes strip. The last stage, starting in the Late Pliocene, is characterized by the E-W foreshortening of the Cervantes Trough, and the beginning of its erosion.

  10. Paleocurrent evidence for lateral displacement of the Pliocene Colorado River delta by the San Andreas fault system, southeastern California

    NASA Astrophysics Data System (ADS)

    Winker, Charles D.; Kidwell, Susan M.

    1986-09-01

    More than 600 paleocurrent measurements from fluvial paleochannels of the early Colorado River delta plain, preserved in the Palm Spring Formation in the Fish Creek Vallecito (FCV) section of southern California, indicate that the FCV section was on the Gulf of California (southeastern) flank of the delta plain as recently as 2.8 Ma. These measurements imply ˜130 km of tectonic translation to the northwest since 2.8 Ma, which can be accounted for by the displacement histories of Baja California and component faults of the San Andreas system. Stratigraphic data from the FCV section and other Neogene localities, when plotted on a palinspastic base, indicate (1) marine transgression of a narrow Gulf of California rift basin and Bouse embayment (site of modern lower Colorado River) by 5.5 Ma, and (2) uplift of the Bouse embayment, initiation of the: lower Colorado River, and southward progradation of the delta to essentially its present position by 4 Ma.

  11. INTELLIGENT COMPUTING SYSTEM FOR RESERVOIR ANALYSIS AND RISK ASSESSMENT OF THE RED RIVER FORMATION

    SciTech Connect

    Kenneth D. Luff

    2002-09-30

    Integrated software has been written that comprises the tool kit for the Intelligent Computing System (ICS). Luff Exploration Company is applying these tools for analysis of carbonate reservoirs in the southern Williston Basin. The integrated software programs are designed to be used by small team consisting of an engineer, geologist and geophysicist. The software tools are flexible and robust, allowing application in many environments for hydrocarbon reservoirs. Keystone elements of the software tools include clustering and neural-network techniques. The tools are used to transform seismic attribute data to reservoir characteristics such as storage (phi-h), probable oil-water contacts, structural depths and structural growth history. When these reservoir characteristics are combined with neural network or fuzzy logic solvers, they can provide a more complete description of the reservoir. This leads to better estimates of hydrocarbons in place, areal limits and potential for infill or step-out drilling. These tools were developed and tested using seismic, geologic and well data from the Red River Play in Bowman County, North Dakota and Harding County, South Dakota. The geologic setting for the Red River Formation is shallow-shelf carbonate at a depth from 8000 to 10,000 ft.

  12. Origin and geometry of Red River Dolomite Reservoirs, Western Williston Basin

    SciTech Connect

    Longman, M.W.; Fertal, T.G.; Glennie, J.S.

    1983-05-01

    Remarkably uniform distribution of limestone, laminated dolomite, and anhydrite as determined from compensated neutron-density logs suggests that the entire Ordovician Red River Formation of the central Williston Basin was deposited in subtidal ''brining-upward'' sequences. Study of cores and thin sections verifies this locally dolomitized fossiliferous wackestones and packstones, laminated to evenly bedded unfossiliferous mudstones (dolomitized in many wells), and bedded anhydrite. No evidence of subaerial exposure was observed in these rock units. Dolomitization in the Red River ''C'' zone is highly localized. An empirical study of dolomite distribution using data from well logs reveals the presence of dozens of pods of dolomite immediately beneath the ''C'' anhydrite. The pods are up to 200 ft (60 m) thick and 1 mi (1.6 km) in diameter and consist of concentered lenses of (1) tight (locally anhydritic) cryptocrystalline dolomite up to 40 ft (12.2 m) thick and 3,300 ft (1,000 m) in diameter, (2) fine to medium-grained porous dolomite that forms the reservoirs, and (3), still farther from the cryptocrystalline dolomite, relatively tight partly dolomitized limestones. could have been found through application of this model and others could be more efficiently developed.

  13. Evidence for synsedimentary coseismic hydraulic fracturing in the Middle Devonian Cedar Valley Group, Plum River Fault Zone of Iowa

    SciTech Connect

    Ludvigson, G.A.; Gonzalez, L.A.; Faulds, J.E. )

    1993-03-01

    Correspondence between the Plum River Fault Zone and stratigraphic asymmetry the Middle Devonian Wapsipinicon and Cedar Valley groups in eastern Iowa have long been considered to record probable paleotectonism. Mesoscopic evidence for Devonian paleotectonism is exposed in strata of the Rapid Mbr of the Little Cedar Fm (Givetian) at the Silver Creek Graben, a 150 m-wide fault block within the Plum River Fault zone in southern Jackson county, Iowa. Little Cedar limestones are cut by multiple generations of brittle microstructures including compound sediment/spar-filled veins, tectonic stylolites that cut bedding at high angles, and late calcite veins coupled with stylolites. Internal sediments filling compound veins are preserved as unfossiliferous early gray and late olive-colored inclusion-rich microspars, both with mottled luminescence. Inclusions in the microspars consist of detrital illite and diagenetic microdolomite. Spars enclosing the internal sediments have a constructional oscillatory luminescent-nonluminescent zonation. Internal sediments in compound veins at Silver Creek Graben apparently were drawn downward through 15--30 m of overlying Cedar Valley carbonates to fill dilational fractures opened by coseismic hydraulic fracturing during the late Givetian erosional episode that followed deposition of the Coralville Fm. Preliminary sampling of cements and gray microspars from compound veins have [delta][sup 18]O values ranging from [minus]6 to [minus]5 [per thousand] and [delta][sup 13]C values ranging from [minus]6.5 to [minus]3 [per thousand]. These components are interpreted to record diagenesis in a meteoric phreatic environment.

  14. The red-cockaded woodpecker on the Savannah River Site: Aspects of reproductive success.

    SciTech Connect

    Johnston, Peter A.; Imm, Donald, W.; Jarvis, William L.

    2004-12-31

    Red-cockaded woodpecker; Road to Recovery. Proceedings of the 4th Red-cockaded woodpecker Symposium. Ralph Costa and Susan J. Daniels, eds. Savannah, Georgia. January, 2003. Chapter 5. Status and Trends of Populations. Pp 224-229. Abstract: The red-cockaded woodpecker (Picoides borealis) population on the Savannah River Site has been closely monitored and studied over the last 17 years. In 1985, the USDA Forest Service Southern Research Station was given responsibility to study and manage this population in an effort to prevent its extirpation. In December 1985, there were only 4 individuals on the site: 1 pair and 2 solitary males. The population had increased to a total of 175 individuals in 42 active clusters in 2002. Although this represents a very successful recovery effort, there has been substantial annual variation in nesting survival from banding to fledging. Data were analyzed to more completely understand the factors affecting reproduction. No significant effects of age of the breeding male and female, years paired, number of helpers, habitat quality, number of nestings, and time of nest initiation were found when comparing reproductive success in 117 nesting attempts from 1999 to 2002. However, the number of neighboring groups had a direct effect on mortality rates, possibly demonstrating the importance of cluster spacing.

  15. Lower Red River Meadow Restoration Project : Biennial Report 1996-97.

    SciTech Connect

    LRK Communications; Wildlife Habitat Institute; Pocket Water, Inc.

    2003-07-01

    The Red River has been straightened and the riparian vegetation corridor eliminated in several reaches within the watershed. The river responded by incision resulting in over-steepened banks, increased sedimentation, elevated water temperatures, depressed groundwater levels, reduced floodplain function, and degraded fish habitat. The Lower Red River Meadow Restoration Project is a multi-phase ecosystem enhancement effort that restores natural physical and biological processes and functions to stabilize the stream channel and establish high quality habitats for fish and wildlife. A natural channel restoration philosophy guides the design and on the ground activities, allowing the channel to evolve into a state of dynamic equilibrium. Two years of planning, two years of restoration in Phases I and II, and one year post-restoration monitoring are complete. By excavating new bends and reconnecting historic meanders, Phase I and II channel realignment increased channel length by 3,060 feet, decreased channel gradient by 25 percent, and increased sinuosity from 1.7 to 2.3. Cross-sectional shapes and point bars were modified to maintain deep pool habitat at low flow and to reconnect the meadow floodplain. Improved soil moisture conditions will help sustain the 31,500 native riparian plantings reestablished within these two phases. Overall, short-term restoration performance was successful. Analyses of long-term parameters document either post-restoration baseline conditions or early stages of evolution toward desired conditions. An adaptive management strategy has helped to improve restoration designs, methods, and monitoring. Lessons learned are being transferred to a variety of audiences to advance the knowledge of ecological restoration and wise management of watersheds.

  16. Mobilization of arsenic and iron from Red River floodplain sediments, Vietnam

    NASA Astrophysics Data System (ADS)

    Postma, Dieke; Jessen, Søren; Hue, Nguyen Thi Minh; Duc, Mai Thanh; Koch, Christian Bender; Viet, Pham Hung; Nhan, Pham Quy; Larsen, Flemming

    2010-06-01

    Sediments from the Red River and from an adjacent floodplain aquifer were investigated with respect to the speciation of Fe and As in the solid phase, to trace the diagenetic changes in the river sediment upon burial into young aquifers, and the related mechanisms of arsenic release to the groundwater. Goethite with subordinate amounts of hematite were, using Mössbauer spectroscopy, identified as the iron oxide minerals present in both types of sediment. The release kinetics of Fe, As, Mn and PO 4 from the sediment were investigated in leaching experiments with HCl and 10 mM ascorbic acid, both at pH 3. From the river sediments, most of the Fe and As was mobilized by reductive dissolution with ascorbic acid while HCl released very little Fe and As. This suggests As to be associated with an Fe-oxide phase. For oxidized aquifer sediment most Fe was mobilized by ascorbic acid but here not much As was released. However, the reduced aquifer sediments contained a large pool of Fe(II) and As that is readily leached by HCl, probably derived from an unidentified authigenic Fe(II)-containing mineral which incorporates As as well. Extraction with ascorbic acid indicates that the river sediments contain both As(V) and As(III), while the reduced aquifer sediment almost exclusively releases As(III). The difference in the amount of Fe(II) leached from river and oxidized aquifer sediments by ascorbic acid and HCl, was attributed to reductive dissolution of Fe(III). The reactivity of this pool of Fe(III) was quantified by a rate law and compared to that of synthetic iron oxides. In the river mud, Fe(III) had a reactivity close to that of ferrihydrite, while the river sand and oxidized aquifer sediment exhibited a reactivity ranging from lepidocrocite or poorly crystalline goethite to hematite. Mineralogy by itself appears to be a poor predictor of the iron oxide reactivity in natural samples using the reactivity of synthetic Fe-oxides as a reference. Sediments were incubated, both unamended and with acetate added, and monitored for up to 2 months. The river mud showed the fastest release of both Fe and As, while the effect of acetate addition was minor. This suggests that the presence of reactive organic carbon is not rate limiting. In the case of the river and aquifer sediments, the release of Fe and As was always stimulated by acetate addition and here reactive organic carbon was clearly the rate limiting factor. The reduced aquifer sediment apparently can sustain slower but prolonged microbially-driven release of As. The highly reactive pools of Fe(III) and As in the river mud could be due to reoxidation of As and Fe contained in the reducing groundwater from the floodplain aquifers that are discharging into the river. Deposition of the suspended mud on the floodplain during high river stages is proposed to be a major flux of As onto the floodplain and into the underlying aquifers.

  17. Modeling regional variation in riverine fish biodiversity in the Arkansas-White-Red River basin

    SciTech Connect

    Schweizer, Peter E; Jager, Yetta

    2011-01-01

    The patterns of biodiversity in freshwater systems are shaped by biogeography, environmental gradients, and human-induced factors. In this study, we developed empirical models to explain fish species richness in subbasins of the Arkansas White Red River basin as a function of discharge, elevation, climate, land cover, water quality, dams, and longitudinal position. We used information-theoretic criteria to compare generalized linear mixed models and identified well-supported models. Subbasin attributes that were retained as predictors included discharge, elevation, number of downstream dams, percent forest, percent shrubland, nitrate, total phosphorus, and sediment. The random component of our models, which assumed a negative binomial distribution, included spatial correlation within larger river basins and overdispersed residual variance. This study differs from previous biodiversity modeling efforts in several ways. First, obtaining likelihoods for negative binomial mixed models, and thereby avoiding reliance on quasi-likelihoods, has only recently become practical. We found the ranking of models based on these likelihood estimates to be more believable than that produced using quasi-likelihoods. Second, because we had access to a regional-scale watershed model for this river basin, we were able to include model-estimated water quality attributes as predictors. Thus, the resulting models have potential value as tools with which to evaluate the benefits of water quality improvements to fish.

  18. Old-growth definition for Red River bottom forests in the eastern United States. Forest Service general technical report

    SciTech Connect

    Shear, T.; Young, M.; Kellison, R.

    1997-05-01

    Our goal was to develop a description of old-growth red river bottom forests of the Southeastern United States. We compared the characteristics of forests described in the scientific literature and forests we examined to various published criteria for old-growth condition. Because red rivers are a relatively new landscape feature (most < 250 years old, resulting from human-induced soil erosion) and because dramatic changes to their floodplains continue to occur, we do not believe that any old-growth red river forests exist. All the stands along these rivers present at European settlement have been cut and/or otherwise severely altered. In the dynamic landscape after settlement, there have been no opportunities for new old-growth forests to develop. Stands older than 50 to 60 years are rare. Therefore, we propose a stand condition called older growth and list the characteristics. With time and stable site conditions, we believe that old-growth and red river forests can develop from older-growth forests.

  19. Role of Growth Faulting in the Quaternary Development of Mississippi-River Delta

    NASA Astrophysics Data System (ADS)

    Mohrig, D.; George, T. J.; Straub, K. M.

    2008-12-01

    We use an industry grade seismic volume and observations of present-day surface topography to resolve the influence of growth faulting on evolution of Mississippi delta in southeastern Louisiana from the Pleistocene to Recent. The volume of seismic data covers an area roughly 1400 square kilometers in size and it resolves many normal faults with displacements that can be tied to movement of Jurassic Louann Salt in the subsurface. We have defined the Quaternary activity associated with 6 of these normal faults by measuring the progressive offset of strata deposited on the delta surface over time. These measurements of fault displacement were restricted to the sedimentary section positioned 150 to 1500 m beneath the delta surface. Total vertical offsets measured within this Quaternary section range from 60 to 150 m. These fault displacements represent abrupt spatial variations in subsidence rate that are between 4 and 8 percent of the regional, long-term deposition rate. Our best estimates for the Quaternary rates of fault displacement vary between 0.1 and 1 mm/yr. Five faults can be connected to deformation of the modern delta surface. Wetland on the footwall is replaced by open water on the hanging wall of these structures. In spite of this evidence for modern surface deformation, the orientations of buried, seismically resolved channel bodies do not appear to be affected by the positions of active growth faults. We will evaluate the competition between subsidence and sedimentation patterns that leads to this style of channelized stratigraphy.

  20. Constructing an Alpine Fault Paleoseismicity Record from Slumped Lacustrine Deposits in the Cascade River Valley, South Westland, New Zealand

    NASA Astrophysics Data System (ADS)

    Coffey, G.; Moy, C. M.; Toy, V. G.; Ohneiser, C.; Howarth, J. D.

    2014-12-01

    The Alpine Fault is a major structure in New Zealand capable of producing earthquakes of magnitude 7 or greater, which delineates the boundary between the Australian and Pacific plates. Paleoseismic records of these earthquakes indicate recurrence intervals of 300 - 400 years over the last 1,300 years. However, there are no pre-Holocene records. Documenting the late Pleistocene record of magnitude, timing, and frequency of earthquakes would significantly reduce uncertainty in hazard analyses. The tectonically complex Cascade River Valley follows the Southern Alpine Fault, where the fault dominantly accommodates strike-slip motion. Two ~7m outcrops of proglacial lacustrine silt are exposed along the river in which, deformed rhythmites bounded by planar laminated rhythmites have been identified. These exhibit a variety of fold geometries in outcrop and x-ray computed tomography (CT) scans, all of which show some degree of asymmetry. Initial radiocarbon ages of 14,400 and 13,300 14C yr BP have been obtained from terrestrial plant material isolated from samples near the base of one outcrop. Given the age range and laminae density, these dates suggest that the rhythmites are varves, but additional radiocarbon dates and CT-scans will be used to confirm this. The deformed horizons are interpreted to be seismites formed by slumping. Earthquake shaking triggers an increase in pore fluid pressure, which destabilises the sublacustrine slope causing failure and the release of silt into the sedimentary system. As silt is transported by downslope shear it is deformed in distinct layers. Displacement of volumes of silt also causes the formation of seiche waves that apply shear stress to lake floor sediments causing further deformation. Deviations in magnetic susceptibility and the declination of magnetic remanence observed underneath and within deformed horizons are interpreted to be a response of earthquake shaking. Data from these different proxies will be presented and compiled to generate a record of earthquake shaking from the Southern Alpine Fault.

  1. [Preliminary analysis of the characteristics of red tide areas in Changjiang River estuary and its adjacent sea].

    PubMed

    Zhou, Mingjiang; Yan, Tian; Zhou, Jingzhong

    2003-07-01

    A review was made on the main environmental characteristics such as currents and water body, diluted water and its turning direction, upwelling, front, nutrients and its sources and plankton community in the Changjiang River estuary and its adjacent sea areas which could affect the growth, migration, assembling, resting and competition of harmful algae to form red tides. Analyses were also conducted to reveal features of the red tides events recorded in this area in terms of time, location and causative species. Some preliminary results from recent cruises carried out in the investigated sea area, where red tides were frequently occurring, were introduced. PMID:14587317

  2. Temporal and spatial distribution of red tide outbreaks in the Yangtze River Estuary and adjacent waters, China.

    PubMed

    Liu, Lusan; Zhou, Juan; Zheng, Binghui; Cai, Wenqian; Lin, Kuixuan; Tang, Jingliang

    2013-07-15

    Between 1972 and 2009, evidence of red tide outbreaks in the Yangtze River Estuary and adjacent waters was collected. A geographic information system (GIS) was used to analyze the temporal and spatial distribution of these red tides, and it was subsequently used to map the distribution of these events. The results show that the following findings. (1) There were three red tide-prone areas: outside the Yangtze River Estuary and the eastern coast of Sheshan, the Huaniaoshan-Shengshan-Gouqi waters, and the Zhoushan areas and eastern coast of Zhujiajian. In these areas, red tides occurred 174 total times, 25 of which were larger than 1000 km(2) in areal extent. After 2000, the frequency of red tide outbreaks increased significantly. (2) During the months of May and June, the red tide occurrence in these areas was 51% and 20%, respectively. (3) Outbreaks of the dominant red tide plankton species Prorocentrum dong-haiense, Skeletonema costatum, Prorocentrum dantatum, and Noctiluca scientillan occurred 38, 35, 15, and 10 times, respectively, during the study interval. PMID:23628547

  3. Integrated and Sustainable Water Management of Red-Thai Binh Rivers System Under Change

    NASA Astrophysics Data System (ADS)

    Giuliani, M.; Anghileri, D.; Castelletti, A.; Mason, E.; Micotti, M.; Soncini-Sessa, R.; Weber, E.

    2014-12-01

    Vietnam is currently undergoing a rapid economic and demographic development, characterized by internal migrations from the rural areas to the main cities with increasing water demands to guarantee adequate energy and food productions. Hydropower is the primary renewable energy resource in the country, accounting for 33% of the total electric power production, while agriculture contributes for 18% of the national GDP and employs 70% of the population. To cope with this heterogeneous and fast-evolving context, water resources development and management have to be reconsidered by enlarging their scope across sectors and by adopting effective tools to analyze the potential of current and projected infrastructure along with their operating strategies. This work contributes a novel decision-analytic framework based on Multi-Objective Evolutionary Direct Policy Search (MOE-DPS) to support the design of integrated and sustainable water resources management strategies in the Red-Thai Binh River system. The Red River Basin is the second largest basin of Vietnam, with a total area of about 169,000 km2, and comprises three main tributaries and several reservoirs, namely SonLa and HoaBinh on the Da River, ThacBa and TuyenQuang on the Lo River. These reservoirs are regulated for maximizing hydropower production, mitigating flood primarily in Hanoi, and guaranteeing irrigation water supply to the agricultural districts in the delta. The dimensionality of the system and the number of objectives involved increase the complexity of the problem. We address these challenges by combining the MOE-DPS framework with Gaussian radial basis functions policy approximation and the Borg MOEA, which have been demonstrated to guarantee good solutions quality in such many objective policy design problems. Results show that the proposed framework successfully identified alternative management strategies for the system, which explore different tradeoffs among the multi-sector services involved. These solutions are then evaluated under various scenarios of climate change and projected socio-economic conditions to identify their vulnerabilities and, possibly, to design improved operating policies, which are more robust to the future uncertainties.

  4. The cost of anaplasmosis in the Red River Plains and south-east areas of Louisiana.

    PubMed

    Morley, R S; Hugh-Jones, M E

    1989-01-01

    Losses from morbidity and mortality due to anaplasmosis were assessed in beef and dairy cattle of the Red River Plains and south-east areas of Louisiana. The cost of treatment and prevention of anaplasmosis and losses in milk production and those due to deaths or culling were valued at $0.5 million for the year 1983 in these two areas. The cost of prevention included the use of tetracyclines in feed and salt-mineral supplements, injectable tetracycline, vaccination and an estimated 10% of the cost of insecticidal ear tags, sprays, pour-on applications and dust bags. The remainder of these costs and the total cost of vector control in dairy cattle was attributed to the control of fly annoyance. Treatment costs included veterinary fees and the owner's treatment costs, including labour costs. PMID:2588475

  5. Morphometric studies of genus Placocheilus (Teleostei: Cypriniformes) from Red River, China

    PubMed Central

    ZHOU, Wei; LI, Min-hui; WANG, Chun-ping; QI, Mi

    2015-01-01

    It is practically difficult to differentiate Placocheilus robustus and Placocheilus caudofasciatus from Red River drainage of China. Without stated reasons, P. robustus has been assumed as the synonyms of P. caudofasciatus. The present study aims to decipher the morphological differences between two species so as to provide reliable clues for their classification by multivariate morphometry. A total of 72 specimens of two species in genus Placocheilus were examined. Besides morphological character comparisons, 10 anatomic landmarks were utilized and 23 frame structures and 15 general characters measured. The scatter plot results of principal component analysis showed that all specimens were clustered together and could not be defined as two distinct species. No significant morphological differences existed in four diagnostic characters between P. robustus and P. caudofasciatus. Thus the results of the present study fail to support P. robustus as a valid and independent species. PMID:26646572

  6. Integration of environmental and spectral data for sunflower stress determination. [Red River Valley, Minnesota

    NASA Technical Reports Server (NTRS)

    Lillesand, T.; Seeley, M.

    1983-01-01

    Stress in sunflowers was assessed in western and northwestern Minnesota. Weekly ground observations (acquired in 1980 and 1981) were analyzed in concert with large scale aerial photography and concurrent LANDSAT data. Using multidate supervised and unsupervised classification procedures, it was found that all crops grown in association with sunflowers in the study area are spectrally separable from one another. Under conditions of extreme drought, severely stressed plants were differentiable from those not severely stressed, but between-crop separation was not possible. Initial regression analyses to estimate sunflower seed yield showed a sensitivity to environmental stress during the flowering and seed development stages. One of the most important biological factors related to sunflower production in the Red River Valley area was found to be the extent and severity of insect infestations.

  7. Preconstruction and postconstruction ground-water levels, Lock and Dam 5 and 6, Red River Valley, Louisiana

    USGS Publications Warehouse

    Ludwig, A.H.; Terry, J.E.

    1979-01-01

    Proposed construction of a series of locks and dams in the Red River in Louisiana will cause a permanent increase in average river stage. The potentiometric surface of the shallow alluvial aquifer and the water table in the fine-grained material confining the aquifer will be affected. The purpose of this study, using digital-modeling techniques, was to predict the average postconstruction potentiometric surface (steady state) and the water table (nonsteady state) so that potential effects of the water-level changes could be evaluated. Plans for lock and dam 5 at mile 243 (kilometer 390) above the mouth of the Red River call for a pool elevation of 145 feet (44 meters) and will cause an average increase in river stage of 23 feet (7.0 meters). As a result, ground-water levels in the pool area will be raised to near land surface in much of the area between the river and Bayou Pierre and as much as 2 miles (3.2 kilometers) east of the river from the dam upstream to realined mile 220 (kilometer 350). Areas of Barksdale Air Force Base where levels are now near land surface would be enlarged and extend downstream along Flat River to near Curtis. The potentiometric surface may be above land surface near Howard, Anderson Island, and Dixie Gardens. (Woodard-USGS)

  8. Strike-slip faulting, topographic growth and block movements as deduced from drainage anomalies: The Yeşilırmak River basin, northern Turkey

    NASA Astrophysics Data System (ADS)

    Gürbüz, Esra; Kazancı, Nizamettin; Gürbüz, Alper

    2015-10-01

    This study aims to understand the various effects of known tectonism on a fluvial network and to interpret the tectonic deformations using described, and analysed systematic anomalies in the drainage basin of the Yeşilırmak River in northern Turkey at countermarch. This region, which is divided into several faulted wedges by right-lateral strike-slip faulting of the North Anatolian fault zone and its individual splays, has experienced several moderate to large earthquakes with high amounts of surface ruptures during the historical and instrumental periods. The Yeşilırmak River basin includes several geomorphic imprints of such widespread and frequent strike-slip deformations. Offsets (between 750 m and 19 km), aligned drainages, and linear valleys (170 km) are expected geomorphic and tectonic responses to strike-slip faulting in the fluvial system. We used such indicators to determine the long term effects of strike-slip faulting in the Yeşilırmak River drainage network. The measured stream offsets represent decreasing values toward southern splay faults consistent with published geodetic data for the region. However, some other large-scale geomorphic anomalies extracted from the drainage network are not explainable by only strike-slip tectonics. Compressional structures, i.e., anticlines, synclines, in the region are responsible for such large-scale drainage diversions (20-24 km) along the river courses. Although these diversions, the North Anatolian fault zone is the main driving force shaping present geomorphology on a regional scale. The Sungurlu-Ezinepazarı fault also plays a critical role in landscape evolution. Their activities and associated block movements have resulted with tilting processes. On the other hand, the entire fluvial network should be modified by the sea level changes of the Black Sea, particularly in the late Quaternary.

  9. Late-summer food of red-winged blackbirds in a fresh tidal-river marsh

    USGS Publications Warehouse

    Meanley, B.

    1961-01-01

    During late summer in the Delaware Valley and Chesapeake Bay region, hundreds of thousands of Red-winged Blackbirds feed in wild rice beds of fresh tidal-river marshes. The period during which wild rice seed is available coincides with the ripening period of a part of the corn crop, and there is evidence to indicate that the availability of the wild rice reduces bird feeding pressure on corn in the area. The importance of wild rice and other marsh plants to the redwing during the period when wild rice seed is available was studied further by field observations and by analysis of stomach contents of 130 birds collected in wild rice beds of the Patuxent River in southern Maryland. Seeds of marsh plants formed the bulk of the food of redwings collected. Dotted smartweed, wild rice, and Walter?s millet were the most important food plants. Corn was the fourth most important item. It occurred in 35, approximately one-fourth, of the stomachs

  10. Holocene delta plain development in the Song Hong (Red River) delta, Vietnam

    NASA Astrophysics Data System (ADS)

    Funabiki, Ayako; Haruyama, Shigeko; Quy, Nguyen Van; Hai, Pham Van; Thai, Dinh Hung

    2007-05-01

    Holocene delta plain development was investigated based on three sediment cores analyzed in detail from the Song Hong (Red River) delta plain in Vietnam. Two cores (DA and PD) from the western delta plain showed both the landward limit of the transgressive estuarine system in the valley incised during the last glacial maximum and floodplain evolution since the middle Holocene. On the other hand, a core (TL) from the eastern delta plain revealed a Pleistocene terrace buried under the deltaic sediments and a slow accumulation rate compared with that in the west. At 8 cal ky BP, the shoreline migrated very close to the present Hanoi city area, and the sedimentary environment changed to tidal flat or salt marsh. Hanoi city marks the northern limit of shoreline transgression. The mangrove swamp expanded from 8 to 5 cal ky BP to the landward limit of the delta plain. Subsequently, the shoreline migrated seaward as a result of delta progradation and sea-level lowering. From 5 cal ky BP, the emerged area evolved into a floodplain and natural levees formed along the abandoned river channels on the western delta plain, but at 2 cal ky, archeological sites indicate that the Holocene terrace in the eastern delta plain was still inundated.

  11. Modeling River Incision Across Active Normal Faults Using the Channel-Hillslope Integrated Landscape Development Model (CHILD): the case of the Central Apennines (Italy)

    NASA Astrophysics Data System (ADS)

    Attal, M.; Tucker, G.; Whittaker, A.; Cowie, P.; Roberts, G.

    2005-12-01

    River systems constitute some of the most efficient agents that shape terrestrial landscapes. Fluvial incision rates govern landscape evolution but, due to the variety of processed involved and the difficulty of quantifying them in the field, there is no "universal theory" describing the way rivers incise into bedrock. The last decades have seen the birth of numerous fluvial incision laws associated with models that assign different roles to hydrodynamic variables and to sediments. In order to discriminate between models and constrain their parameters, the transient response of natural river systems to a disturbance (tectonic or climatic) can be used. Indeed, the different models predict different kinds of transient response whereas most models predict a similar power law relationship between slope and drainage area at equilibrium. To this end, a coupled field - modeling study is in progress. The field area consists of the Central Apennines that are subject to active faulting associated with a regional extensional regime. Fault initiation occurred 3 My ago, associated with throw rates of 0.3 +/- 0.2 mm/yr. Due to fault interaction and linkage, the throw rate on the faults located near the center of the fault system increased dramatically 0.7 My ago (up to 2 mm/yr), whereas slip rates on distal faults either decayed or remained approximately constant. The present study uses the landscape evolution model, CHILD, to examine the behavior of rivers draining across these active faults. Distal and central faults are considered in order to track the effects of the fault acceleration on the development of the fluvial network. River characteristics have been measured in the field (e.g. channel width, slope, sediment grain size) and extracted from a 20m DEM (e.g. channel profile, drainage area). We use CHILD to test the ability of alternative incision laws to reproduce observed topography under known tectonic forcing. For each of the fluvial incision models, a Monte-Carlo simulation has been performed, allowing the exploration of a wide range of values for the different parameters relative to tectonic, climate, sediment characteristics, and channel geometry. Observed profiles are consistent with a dominantly wave-like, as opposed to diffusive, transient response to accelerated fault motion. The ability of the different models to reproduce more or less accurately the catchment characteristics, in particular the specific profiles exhibited by the rivers, are discussed in light of our first results.

  12. Reconnaissance of mercury in lakes, wetlands, and rivers in the Red River of the North Basin, North Dakota, March through August 2001

    USGS Publications Warehouse

    Sando, Steven K.; Wiche, G.J.; Lundgren, R.F.; Sether, Bradley A.

    2003-01-01

    Devils Lake rose dramatically during the 1990's, causing extensive flood damages. Because of the potential for continued flooding, the U.S. Army Corps of Engineers has been conducting studies to evaluate the feasibility of constructing and operating an outlet from Devils Lake. The occurrence of mercury in lakes, wetlands, and rivers and the potential for increased loading of mercury into the Sheyenne River as a result of a Devils Lake outlet needed to be evaluated as part of the studies. Sixteen lake, wetland, and river sites in the Devils Lake, Sheyenne River, Red River of the North, and Red Lake River Basins were sampled and analyzed for mercury constituents and other selected properties and constituents relevant to mercury aquatic chemistry. For the lake and wetland sites, whole-water methylmercury concentrations ranged from less than 0.04 to 3.53 nanograms per liter and whole-water total mercury concentrations ranged from 0.38 to 7.02 nanograms per liter. Conditions favorable for methylation of mercury generally exist at the lake and wetland sites, as indicated by larger dissolved methylmercury concentrations in near-bottom samples than in near-surface samples and by relatively large ratios of methylmercury to total mercury (generally greater than 10 percent for the summer sampling period). Total mercury concentrations were larger for the summer sampling period than for the winter sampling period for all lake and wetland sites. A wetland site in the upper Devils Lake Basin had the largest mercury concentrations for the lake and wetland sites. For the river sites, whole-water methylmercury concentrations ranged from 0.15 to 1.13 nanograms per liter and whole-water total mercury concentrations ranged from 2.00 to 26.90 nanograms per liter. Most of the mercury for the river sites occurred in particulate inorganic phase. Summer ratios of whole-water methylmercury to whole-water total mercury were 35 percent for Starkweather Coulee (a wetland-dominated site), near or less than 10 percent for the Sheyenne River sites, and less than 8 percent for the Red River of the North and Red Lake River sites. Although the number of samples collected during this investigation is small, results indicated an outlet from Devils Lake probably would not have adverse effects on mercury concentrations in the Sheyenne River upstream from Lake Ashtabula. However, because discharges in the Sheyenne River would increase during some periods, loads of mercury entering Lake Ashtabula also would increase. Lake Ashtabula probably serves as a sink for suspended sediment and mercury. Thus, a Devils Lake outlet probably would not have substantial effects on mercury concentrations and loads in the downstream part of the Sheyenne River or in the Red River of the North. More substantial effects could occur for Lake Ashtabula.

  13. Holocene evolution of the Song Hong (Red River) delta system, northern Vietnam

    NASA Astrophysics Data System (ADS)

    Tanabe, Susumu; Saito, Yoshiki; Lan Vu, Quang; Hanebuth, Till J. J.; Lan Ngo, Quang; Kitamura, Akihisa

    2006-05-01

    The Song Hong (Red River) delta, located on the western coast of the Gulf of Bac Bo (Tonkin) in the South China Sea, formed as a result of the Song Hong sediment discharge throughout the Holocene. The river's sedimentary basin upstream from the delta plain is not large. The delta plain comprises emerged tidal/mangrove flats formed during the sea-level highstand at + 2-3 m (6-4 cal. kyr BP) and a beach-ridge strandplain, with straight-to-lobate beach ridges, on the landward and seaward sides of the delta plain, respectively. The delta affords us the opportunity to examine river-mouth morphodynamics comprehensively in relation to sediment discharge and sea-level changes. In this paper, we describe the Holocene evolution of the Song Hong delta system and the river-mouth morphodynamics on the basis of seven sediment cores, each 30-70 m long, taken from the delta plain during 1999-2001 and 101 radiocarbon dates obtained from the core sediments. Sediments from the seven cores, consisting of incised-valley fills since the last glacial maximum, can be divided, in ascending order, into fluvial sediments composed of gravelly sand and mottled clay, tide-influenced estuarine sediments containing shell and wood fragments, and deltaic sediments composed of tide-influenced sand and mud deposits, in which the contents of sand and wood fragments increase upward. By applying sequence stratigraphic concepts, a transgressive surface can be identified at the gravelly sand-mottled clay boundary, and the maximum flooding surface can be identified at the estuarine-deltaic sediments boundary. The lowstand systems tract, transgressive systems tract, and highstand systems tract record 15, 15-9, and 9-0 cal. kyr BP, respectively. During the past 9 kyr, the majority of the sediment discharged by the Song Hong accumulated in the incised valley and enhanced progradation at the river mouth. The river mouth prograded from the bay head toward the gulf, and its morphology changed from funnel-shaped (9-6 cal. kyr BP) to straight (6-2 cal. kyr BP) and finally to lobate (2-0 cal. kyr BP). The morphological change from a funnel-shaped to straight coast is interpreted to have been closely related to a hydrologic regime shift from a tide-dominated bay-head setting to a wave-influenced open-coast setting. The cessation of the sea-level rise at 6 cal. kyr BP may have played only a small role in the change of river-mouth morphology because the progradation rate decelerated from 22 to 4 m/yr, instead of accelerating at that time. The river-mouth morphodynamic change from straight to lobate was largely caused by an increase in the Song Hong sediment discharge from 17-27 (9-2 cal. kyr BP) to 49 million t/yr (2-0 cal. kyr BP) as a result of anthropogenic deforestation along the upper reaches of the Song Hong.

  14. Aquatic communities and contaminants in fish from streams of the Red River of the North basin, Minnesota and North Dakota

    USGS Publications Warehouse

    Goldstein, R.M.

    1995-01-01

    Available data on the ecology of aquatic organisms in the Red River of the North Basin, a study unit of the U.S. Geological Survey's National Water-Quality Assessment program, were collated from numerous sources. Lack of information for invertebrates and algae precluded a general summary of distribution and ecology throughout the basin. Data on fish species distributions in the major streams of the Red River of the North Basin were analyzed based on the drainage area of the stream and the number of ecoregions the stream flowed through. Species richness increased with both drainage area (log drainage area in square kilometers, R2=0.41, p=0.0055) and the number of ecoregions a river flowed through. However, theses two factors are autocorrelated because the larger the drainage, the more likely that the river will flow through more than one ecoregion. A cluster analysis identified five river groups based on similarity of species within the fish community. Analysis of trophic and taxonomic composition provided justification for the cluster groups. There were significant differences (p=0.05) in the trophic composition of the river cluster groups with respect to the number of predator species, omnivore species, benthic insectivore species, and general insectivore species. Although there were no significant differences in the number of species in the bass and sunfish family or the sucker family, the number of species in the minnow family and the darter subfamily were different (p=0.05) among the groups identified by cluster analysis. Data on contaminant concentrations in fish from the Red River of the North indicated that most trace elements and organochlorine compounds present in tissues were not at levels toxic to fish or humans. Minnesota and North Dakota have issued a fish consumption advisory based on levels of mercury and (or) PCBs found in some species.

  15. Establishment of a Viable Population of Red-Cockaded Woodpeckers at the Savannah River Site

    SciTech Connect

    Johnston, P.A.

    2002-01-14

    Report on program's objective to restore viable population of Red-cockaded woodpecker at SRS. Several management strategies were used to promote population expansion of Red-cockaded woodpecker and reduction of interspecific competition with Red-Cockaded woodpecker.

  16. Red Planet? Red River!FIELD Works on the Red-Mud Flood Polluted Marcal Riverside: ph Measurements by the HUSAR-5 Nxt-Based Rover Model of the SZÉCHENYI ISTVÁN High School, Sopron, Hungary.

    NASA Astrophysics Data System (ADS)

    Lang, A.; Cserich, D.; Kiss, D.; Erdélyi, S.; Nickl, I.; Bérczi, S.

    2011-10-01

    On October 4, 2010, heavy industrial catastrophe polluted the Marcal river in West-Hungary. The Red-mud sludge, the byproduct of the alumina production, poured from a containment pond because of the broken dike. The environmental pollution first appeared in the creeks and rivers in the vicinity of the alumina plant at Ajka. Earlier our group prepared pH measurement robotics on the HUSAR-5 rover therefore our idea was to carry out - a planetary analog type - field works with the rover on the polluted region. The locality was about 100 kilometrs from our town, Sopron. We visited 3 times the region.

  17. Dynamic Emulation Modeling of irrigation water deficit in the Red-Thai Binh River Delta, Vietnam

    NASA Astrophysics Data System (ADS)

    Dinh, Q.; Cassaro, L.; Micotti, M.; Soncini-Sessa, R.

    2013-12-01

    Water deficit (WD) is the factor that most affects agricultural productivity in irrigated land. The optimal management of water resources requires estimating and forecasting its intensity in space and time. In large irrigation systems, the adoption of a physically-based (PB), distributed, dynamic model (e.g.Mike11) is a viable solution, since it can simulate the hydraulic processes that occurs in the system, including the operation of hydraulic structures according with rules based on water demand and water availability. However PB models always have a high dimensional state that prevents their adoption within optimization algorithms, even the most advanced ones. Additionally, the information they produce (the time trajectories of all the variables of the systems) is definitively larger than what is actually required (the trajectories of WDs in pre-specified areas) in the management problem. Thus input/output (I/O) lumped models would be more appropriate, but their calibration is generally prevented by the lack of sufficiently long time series of the output variables (WDs in our case). The solution we explored is to split the process into two steps: the first is the calibration of a PB model (Mike11 in our case study) in a traditional way, using the available time series; the second is the identification of an I/O model from the WD time series generated by the PB model We present a dynamic emulation modelling (DEMo) approach which leads to the identification of an emulation model, namely a simplified, computationally-efficient model built over a sample data-set produced via simulation of the original model (Mike11). The core mechanism of the procedure is a feature-ranking algorithm, based on Extremely Randomized Trees, through which the suitable input variables of the emulation model are automatically selected. The emulation model, in the form of an I/O relationship, is then identified using Artificial Neural Networks. The proposed approach is demonstrated on a real-world case study: the Red-Thai Binh River Delta in Vietnam. It is a large and complex river system, supplied by five unregulated rivers and four large multi-purpose reservoirs, the operating rules of which have to be designed. In order to ascertain the effects of their regulation on the WD in the Delta, a Mike11 model was calibrated and validated. It describes 320 rivers and canals for a total length of 4200 km, 11 irrigation districts and many structures, among which 88 sluice gates and 302 irrigation water intakes (simulated as controlled pumps). Its inputs are the four reservoirs releases, the non-regulated flows of the five rivers, the sea levels at the nine river mouths, the water demand at each one of the irrigation water intakes. The considered outputs are the daily WD in the 11 districts. The dimension of the state vector of the model is of the order of 16,000. From the high dimensional Mike11, a low dimensional (11 dimension) DEMo model was identified that mimics very well (R2=0.95) the WDs as computed by the Mike11 model. The DEMo model will be later on embedded within a large multi-objective optimal control problem to design the operating rules of the four reservoirs.

  18. Basin-scale characterization of river hydromorphology by map derived information: A case study on the Red River (Sông Hông), Vietnam

    NASA Astrophysics Data System (ADS)

    Schmitt, R. J.; Bizzi, S.; Castelletti, A.

    2012-12-01

    The understanding of river hydromorphological processes has been recognized in the last decades as a priority of modern catchment management, since fluvial geomorphic processes shape physical habitat, affect river infrastructures and influence freshwater ecological processes. Characterization of river hydromorphological features is commonly location specific and highly demanding in terms of field-works, resource and expertise required. Therefore, its routine application at regional or national scales, although an urgent need of catchment management, is infeasible at present. Recently available high-resolution data, such as DEM or LIDAR, opens up novel potential for basin-wide analysis of fluvial processes at limited effort and cost. Specifically, in this study we assess the feasibility of characterizing river hydromorphology from specific map derived geomorphic controls namely: channel gradient, bankfull flow, specific stream power, and degree of channel confinement. The river network, extracted from a digital elevation model and validated with available network shape-files and optical satellite imagery, available flow gauging stations and GIS processing allow producing continuous values of geomorphic drivers defined over given length segments at catchment or regional scales. This generic framework was applied to the Red River (Sông Hông) basin, the second largest basin (87,800 km2) in Vietnam. Besides its economic importance, the river since few years is experiencing severe river bed incisions due to the building of new dams in the upstream part of the catchment and sand mining in the surrounding of the capital city Hanoi. In this context, characterized by an high developing rate, current efforts to increase water productivity by infrastructure and management measures require a thorough understanding of fluvial system and, in particular, of the basin-wide river hydromorphology. The framework proposed has allowed producing high-dimensional samples of spatially distributed geomorphic drivers at catchment scale for the Red River basin. This novel dataset has been then analysed using self-organizing maps (SOM) an artificial neural network model that is capable of learning from complex, multidimensional data without specification of what the outputs should be, and of generating a nonlinear classification of visually decipherable clusters. The use of the above framework allowed to analyze the spatial distribution of geomorphic features at catchment scale, reviling patterns of similarities and dissimilarities within the catchment and allowing classification of river reaches characterized by similar geomorphic drivers and then likely (but still to be validated) fluvial processes. The paper proposes an innovative and promising technique to produce hydromorphological classifications at catchment scale opening the way towards regional or national scale hydromorphological assessments through automatic GIS and statistical procedures with moderate effort, an urgent requirement of modern catchment management.

  19. An Inverse Fault Detection From Shallow Geophysical Data at the P Reactor Area, Savannah River Site, South Carolina

    NASA Astrophysics Data System (ADS)

    Cameron, A. E.; Knapp, C. C.; Addison, A. D.; Waddel, M.

    2008-12-01

    Surface and borehole Ground Penetrating Radar (GPR), a Shallow Seismic Reflection (SSR) as well as Electrical Resistivity Tomography (ERT) surveys were conducted at Savannah River Site (SRS), South Carolina, in order to investigate the shallow stratigraphy, hydrogeophysical zonation, and the applicability and performance of these imaging techniques. The study site is the P Reactor Area located within the Upper Atlantic Coastal Plain, with clastic sediments ranging from Late Cretaceous to Miocene age. Lithologies consist of sand, clayey sand, and clay with minor amounts of calcareous minerals. The target of this research is the delineation and prediction of migration pathways of a large contaminant plume including trichloroethylene (TCE) that originates from the northwest section of the reactor facility and discharges into the nearby Steel Creek. Here, we present results from stratigraphic and hydrogeophysical characterizations using (1) the GPR technique involving the PulseEKKO 100 GPR system with 50, 100, and 200 MHz antennas, (2) the SSR method with a Geometrics 120-channel seismograph, and (3) the ERT technique with the SuperSting R8 IP with 8-channel multi-electrode resistivity and IP imaging system. Faulting on the GPR, SSR and ERT profiles may be observed through offsets of reflecting interfaces, dipping discontinuities, or fault plane imaging, all leading to a constrained interpretation of a fault system at the study site. The simultaneous use of the 50, 100 and 200 MHz antennas with the SSR and ERT methods allows us to generate a geologic cross-section of the subsurface to perform analyes of the radar and acoustic reflection data as a function of frequency, conductivity and acoustic impedance to facilitate interpolation and extrapolation of the hydraulic properties such as hydraulic conductivity (K) and porosity of the study area.

  20. Hydrogeology and Physical Characteristics of Water Samples at the Red River Aluminum Site, Stamps, Arkansas

    NASA Astrophysics Data System (ADS)

    Czarnecki, J. B.; Stanton, G. P.; Freiwald, D. A.

    2001-12-01

    The Red River Aluminum site near Stamps, Arkansas, contains waste piles of salt cake and metal byproducts from the smelting of aluminum. The waste piles are subjected to about 50 inches of rainfall a year, resulting in the dissolution of the salts and metal. To assess the potential threat to underlying ground-water resources at the site, its hydrogeology was characterized by measuring water levels and field parameters of water quality in 23 wells and at 2 surface-water sites. Seventeen of these monitor wells were constructed at various depths for this study to allow for the separate characterization of the shallow and deep ground-water systems, the calculation of vertical gradients, and the collection of water samples at different depths within the flow system. Lithologic descriptions from drill-hole cuttings and geophysical logs indicate the presence of interbedded sands, gravels, silts, and clays to depths of 65 feet. The regionally important Sparta aquifer underlies the site. Water levels in shallow wells indicate radial flow away from the salt-cake pile located near the center of the site. Flow in the deep system is to the west and southwest toward Bodcau Creek. Water-level data from eight piezometer nests indicate a downward hydraulic gradient from the shallow to deep systems across the site. Values of specific conductance (an indicator of dissolved salts) ranged from 215 to 196,200 microsiemens per centimeter and indicate that saline waters are being transported horizontally and vertically downward away from the site.

  1. Red River Wildlife Management Area HEP Report, Habitat Evaluation Procedures, Technical Report 2004.

    SciTech Connect

    Ashley, Paul

    2004-11-01

    A habitat evaluation procedures (HEP) analysis conducted on the 314-acre Red River Wildlife Management Area (RRWMA) managed by the Idaho Department of Fish and Game resulted in 401.38 habitat units (HUs). Habitat variables from six habitat suitability index (HSI) models, comprised of mink (Mustela vison), mallard (Anas platyrhynchos), common snipe (Capella gallinago), black-capped chickadee (Parus altricapillus), yellow warbler (Dendroica petechia), and white-tailed deer (Odocoileus virginianus), were measured by Regional HEP Team (RHT) members in August 2004. Cover types included wet meadow, riverine, riparian shrub, conifer forest, conifer forest wetland, and urban. HSI model outputs indicate that the shrub component is lacking in riparian shrub and conifer forest cover types and that snag density should be increased in conifer stands. The quality of wet meadow habitat, comprised primarily of introduced grass species and sedges, could be improved through development of ephemeral open water ponds and increasing the amount of persistent wetland herbaceous vegetation e.g. cattails (Typha spp.) and bulrushes (Scirpus spp.).

  2. Characterisation of Adaptive Genetic Diversity in Environmentally Contrasted Populations of Eucalyptus camaldulensis Dehnh. (River Red Gum)

    PubMed Central

    Dillon, Shannon; McEvoy, Rachel; Baldwin, Darren S.; Rees, Gavin N.; Parsons, Yvonne; Southerton, Simon

    2014-01-01

    As an increasing number of ecosystems face departures from long standing environmental conditions under climate change, our understanding of the capacity of species to adapt will become important for directing conservation and management of biodiversity. Insights into the potential for genetic adaptation might be gained by assessing genomic signatures of adaptation to historic or prevailing environmental conditions. The river red gum (Eucalyptus camaldulensis Dehnh.) is a widespread Australian eucalypt inhabiting riverine and floodplain habitats which spans strong environmental gradients. We investigated the effects of adaptation to environment on population level genetic diversity of E. camaldulensis, examining SNP variation in candidate gene loci sampled across 20 climatically diverse populations approximating the species natural distribution. Genetic differentiation among populations was high (FST = 17%), exceeding previous estimates based on neutral markers. Complementary statistical approaches identified 6 SNP loci in four genes (COMT, Dehydrin, ERECTA and PIP2) which, after accounting for demographic effects, exhibited higher than expected levels of genetic differentiation among populations and whose allelic variation was associated with local environment. While this study employs but a small proportion of available diversity in the eucalyptus genome, it draws our attention to the potential for application of wide spread eucalypt species to test adaptive hypotheses. PMID:25093589

  3. Hydrogeochemical characteristics of groundwater from the two main aquifers in the Red River Delta, Vietnam

    NASA Astrophysics Data System (ADS)

    Nguyen, Thuy Thanh; Kawamura, Akira; Tong, Thanh Ngoc; Nakagawa, Naoko; Amaguchi, Hideo; Gilbuena, Romeo

    2014-10-01

    In the Red River Delta, situated in the northern part of Vietnam, nearly its entire population depends solely on groundwater for daily water consumptions. For this reason, groundwater quality assessments must be carefully carried out using hydrogeochemical properties, to ensure effective groundwater resource planning for the Delta’s present and future groundwater use. In this study, the spatial and seasonal changes in the hydrogeochemical characteristics of groundwater in the two main aquifers of the RRD were investigated by analyzing the physicochemical data obtained in 2011 from 31 conjunctive wells in the Delta’s Holocene unconfined aquifer (HUA) and Pleistocene confined aquifer (PCA) using the Piper diagram and the Gibbs diagram. Results of the data analysis show that the groundwater in both aquifers in the upstream area of the delta is dominated by the [Ca2+-HCO3-] water-type, while the [Na+-Cl-] dominates along the middle-stream and downstream areas. Seasonal changes in the hydrogeochemical facies in both aquifers, comparing the results for the dry and the rainy seasons, were detected in about one third of the sampling wells, which were mainly located at the upstream portion of the Delta. The hydrogeochemical facies of HUA were different from that of PCA by about 45% of the sampling wells in both the dry and the rainy seasons, which were found mostly in the upstream and middle-stream areas.

  4. A subsynoptic-scale kinetic energy study of the Red River Valley tornado outbreak (AVE-SESAME 1)

    NASA Technical Reports Server (NTRS)

    Jedlovec, G. J.; Fuelberg, H. E.

    1981-01-01

    The subsynoptis-scale kinetic energy balance during the Red River Valley tornado outbreak is presented in order to diagnose storm environment interactions. Area-time averaged energetics indicate that horizontal flux convergence provides the major energy source to the region, while cross contour flow provides the greatest sink. Maximum energy variability is found in the upper levels in association with jet stream activity. Area averaged energetics at individual observation times show that the energy balance near times of maximum storm activity differs considerably from that of the remaining periods. The local kinetic energy balance over Oklahoma during the formation of a limited jet streak receives special attention. Cross contour production of energy is the dominant local source for jet development. Intense convection producing the Red River Valley tornadoes may have contributed to this local development by modifying the surrounding environment.

  5. Influence of Organic Agriculture on the Net Greenhouse Effect in the Red River Valley, Minnesota

    NASA Astrophysics Data System (ADS)

    Phillips, R. L.

    2004-12-01

    Fluxes for the suite of biologically-produced greenhouse gases (CH4, N2O and CO2) are strongly influenced by agriculture, yet the influence of organic agriculture on all three gases, which comprise the net greenhouse effect (GHE), is not clear in the context of large-scale agricultural production. Greenhouse gas mitigation potential will depend upon the net balance for all three gases [GHE balance (CO2 equiv.)= CO2 flux+ 23CH4flux + 296N2Oflux]. On-farm, field-scale experiments were performed to test the hypothesis that the net GHE at the soil-atmosphere interface is reduced under organic wheat production, compared with conventional, and that effects vary inter-seasonally. Trace gas fluxes were measured at the soil-atmosphere interface for organic and conventional wheat farms in the Red River Valley, Minnesota, one of the most productive agricultural regions in the US. We utilized 40-60 ha field pairs planted with hard red spring wheat (Triticum aestivum L.). Treatment pairs were located 6km apart and consisted of fields continuously cropped for wheat/soybean/sugar beet production for over 20 yr. Ten random, permanent points were generated for each 8.1 ha sub-plot nested inside each field. Each field pair was similar with respect to crop, climate, cultivation history, tillage, rotation, soil texture, pH, macronutrients, bulk density, and water holding capacity. Differences between treatments for the last five years were soil amendments (compost or urea) and herbicide/fungicide application versus mechanical weed control. We collected gas fluxes at each of the 41 points from April (wheat emergence) until the end of July (maturity) to determine the hourly and seasonally integrated net GHE for each management practice, given similar soil/plant/climatic conditions. Moreover, we analyzed inter-seasonal variability to determine the relationship between wheat phenology and flux under field conditions for soil temperature and moisture (water-filled pore space). The net GHE for organic fields was less spatially and temporally variable than conventional, with average daily flux between 0.48 and 1.44 g CO2 equiv. m-2 d-1. Average daily flux in conventional fields ranged between 0.48 and 3.12 g CO2 equiv. m-2 d-1, with highest values in April and May. While soil moisture in organic fields was significantly greater than conventional, it did not interact with treatment to affect trace gas flux. Instead, the effect of organic on N2O, CO2 and the net GHE was strongly influenced by crop stage, an agronomically meaningful proxy integrating time and plant growth conditions. Most CH4 flux observations were 0. Integrated fluxes for each of the 40 sites over the growing season was averaged by field pair and treatment. Although the magnitude of the treatment effect for average seasonal integrated flux varied between field pairs for CO2 and N2O fluxes, the overall influence of treatment on the net GHE was similar. Overall, soils under organically produced wheat emitted 200 kg CO2 equiv. ha-1 per season less than conventionally produced wheat. We observed 1) the net GHE for similar field sites in the Red River Valley was reduced under organic versus conventional agriculture, 2) N2O flux in organic fields was significantly lower than conventional fields for both field pair sites, and 3) the effect of treatment on CO2 flux was site specific.

  6. Evaluating the Invasion of Red Cedar (Juniperus viriginiana) Downstream of Gavins Point Dam, Missouri National Recreational River

    NASA Astrophysics Data System (ADS)

    Greene, S.; Knox, J. C.

    2013-12-01

    Gavins Point Dam, the final dam on the main-stem Missouri River, alters downstream river form and function. Throughout a 59-mile downstream reach, the dam reduces overbank flooding and lowers the water surface by 1-3 meters. Under the dam-created hydro-geomorphic conditions, native cottonwood trees are unable to regenerate. The limited regeneration of native riparian cottonwoods, the lowered water surface, and the reduced overbank flooding creates a terrace environment within the riparian habitat. Consequently, red cedars, a native upland tree, are invading this new terrace-like riparian environment. To this end, we apply Bayesian statistical models to investigate patterns of red cedar riparian invasion and assess ecosystem function patterns along this flow-regulated reach. We set up plots within cottonwood stands along a 59-km reach downstream of Gavins Point Dam. Within each plot, we collected soil samples, litter samples, stem densities of trees, and collected cores of the largest cottonwood and largest red cedar in each plot. To assess influences of red cedar on soil indicators of ecosystem function and general patterns of ecosystem function within the study area, we measured organic carbon, nitrogen, pH, electrical conductivity, and hydrophobicity. To determine drivers and patterns of invasion and ecosystem function we conducted Bayesian linear regressions and means comparison tests. Red cedars existed along the floodplain prior to regulation. However, according to our tree age data and stem density data red cedars existed at a lower population than today. We found that 2 out of 565 red cedars established before the dam was completed. Also, we found no significant difference in soil properties between soils with established red cedar and soils with established cottonwood. By studying soil texture data, and interpreting fluvial geomorphic surfaces in the field and via aerial photography, we found soil texture generally reflects the type of fluvial surface created before or at the beginning of flow regulation. Red cedar establishment and soil property differences are correlated to percent sand in the soil. According to our interpretation of geomorphic surfaces, the sandier soils represent higher energy depositional surfaces, such as islands and pointbars. Thus, these legacy geomorphic surfaces are a determinant of red cedar establishment patterns and soil property patterns. Land managers and other researchers needing to make predictions for other areas can use our model-building process to quickly map and assess impacts of invasion. In addition, our results show how a Bayesian model provides information about feedbacks between environmental parameters that can help determine and target restoration goals.

  7. Using 10Be erosion rates and fluvial channel morphology to constrain fault throw rates in the southwestern Sacramento River Valley, California, USA

    NASA Astrophysics Data System (ADS)

    Cyr, A. J.

    2013-12-01

    The Sacramento - San Joaquin River Delta, California, USA, is a critical region for California water resources, agriculture, and threatened or endangered species. This landscape is affected by an extensive set of levees that enclose artificial islands created for agricultural use. In addition to their importance for sustaining agriculture, this levee system also supports extensive transport and power transmission infrastructure and urban/suburban development. These levees are susceptible to damage from even moderate ground shaking by either a large earthquake on one of the high-activity faults in the nearby San Francisco Bay region, or even a moderate earthquake on one of the low-activity faults in the Delta region itself. However, despite this danger the earthquake hazards in this region are poorly constrained due to our lack of understanding of faults in and near the Delta region. As part of an effort to better constrain the seismic hazard associated with known, but poorly constrained, faults in the region, a geomorphic analysis of the Dunnigan Hills, northwest of Woodland, CA, is being combined with cosmogenic 10Be catchment-averaged erosion rates. The Dunnigan Hills are a low-relief (maximum elevation 87 m) landscape generated by fault-bend folding above the west-vergent Sweitzer reverse fault that soles into a blind east-vergent reverse fault. These faults have been imaged by seismic reflection data, and local microseismicity indicates that this system is actively propagating to the east. However, the throw rates on the faults in this system remain unconstrained, despite the potential for significant shaking such as that experienced in the nearby April, 1892 earthquake sequence between Winters and Vacaville, Ca, ~25 km to the south, which has been estimated at magnitude 6.0 or greater. Geomorphic and cosmogenic 10Be analyses from 12 catchments draining the eastern flank of the Dunnigan Hills will be used to infer vertical rock uplift rates to better constrain activity on the west-vergent Sweitzer fault and the east-vergent blind reverse fault. All of the sampled catchments are underlain exclusively by Tehama Sandstone. Moreover, there are no mapped surface traces of faults in the sampled catchments. This minimizes the possibility of changes in lithogic resistance to impact the erosion rates and channel analyses. These analyses, combined with fault geometries derived from published seismic reflection data and structural cross sections, allows us to constrain the throw rates on these faults and thus better evaluate the associated seismic hazard.

  8. National Water-Quality Assessment Program: Data Collection in the Red River of the North Basin, Minnesota, North Dakota, and South Dakota, 1992-95

    USGS Publications Warehouse

    Stoner, J.D.; Lorenz, D.L.

    1995-01-01

    A water-quality assessment began in 1991 for the Red River of the North (Red River) Basin as part of a national study. Data collection for the reconnainssance and intensive phases of the study briefly is described for each of the major components (streams, aquatic biology, and ground water) used to assess regional water quality. The data will be analyzed to address national and local water-quality concerns.

  9. Evidence of Late Quaternary Faulting along the Northeastern Segment of the Stagner Creek Fault in the Northwestern Wind River Basin, Wyoming

    NASA Astrophysics Data System (ADS)

    Abousaif, A.; Wang, H.; Cochran, W. J.; Hinrichs, N.; Gomez, F.; Sandvol, E. A.

    2012-12-01

    The Stagner Creek fault, located along the southern margin of the Owl Creek Mountains in central Wyoming, is one of several east-west striking Quaternary faults that may correspond with scattered, present-day, intraplate seismicity in the region. These Quaternary faults are peculiar in that they strike nearly orthogonal to the Basin and Range faults observed in western Wyoming, and their orientation may reflect the influence of inherited, Laramide structures. These east-west striking faults are inferred to be predominantly normal faults. Previous studies have documented the Quaternary activity of the Stagner Creek fault affecting 6 distinct alluvial fan southeast of the Boysen Reservoir. This study aims to expand on these prior efforts using geomorphic and geophysical analyses. In this area, the Stagner Creek fault is expressed as a prominent scarp, visible in air photos and satellite imagery. Microtopographic mapping was accomplished using a real-time kinematic GPS surveying. The resulting DEM provides detailed scarp morphology, as well as documenting possible knick points within the alluvial surfaces upstream from the scarp. The alluvial surface has a regional slope of 2-3 degrees, and the scarp face has a relatively shallow slope of 6-12 degrees. Scarp heights range from 0.4 to 2 meters. The minimum scarp may reflect a single faulting event, corresponding with a magnitude 6.5 - 6.7. These surfaces are believed to be Late Pleistocene and younger, and geochronological constraints are pending. A shallow seismic reflection profile acquired across the scarp imaged structure to depths of about 500 meters. The profile suggests a steep fault coincident with the surface scarp that offsets Tertiary reflectors several 10s of meters in the subsurface. The steep dip is similar to Laradmide structures. These results suggest that the Stagner Creek fault is capable of generating moderate magnitude earthquakes in this low-strain tectonic environment.

  10. News and Views: Airborne radar reveals fault rupture detail; Rhapsody in blue, not red; Ammunition for dark skies activists

    NASA Astrophysics Data System (ADS)

    2010-08-01

    Satellite synthetic aperture radar is a valuable tool for understanding the deformation of the surface of the Earth at earthquake faults; now NASA scientists have used SAR on planes to get an altogether closer look at quake effects. A campaign in Texas to raise awareness of light pollution has produced resources including a video, highlighting causes, effect and solutions, available online.

  11. Assessing trends in organochlorine concentrations in Lake Winnipeg fish following the 1997 red river flood

    USGS Publications Warehouse

    Stewart, A.R.; Stern, G.A.; Lockhart, W.L.; Kidd, K.A.; Salki, A.G.; Stainton, M.P.; Koczanski, K.; Rosenberg, G.B.; Savoie, D.A.; Billeck, B.N.; Wilkinson, Philip M.; Muir, D.C.G.

    2003-01-01

    As we move toward the virtual elimination of persistent organic pollutants (POPs) in the environment our understanding of how short-term variability affects long-term trends of POPs in natural populations will become increasingly more important. In this study we report short-term trends in organochlorine (OC) levels in fish from Lake Winnipeg in the months and years following the 1997 100-year flood of the Red River ecosystem. Our goal was to understand the effects of an episodic event on OC levels in benthic and pelagic invertebrates and in fish. Despite elevated loading of OCs into the south basin of Lake Winnipeg during the flood there were no differences in OC levels of surface sediments or emergent mayflies. After adjusting for differences in lipid content and length among sample times, we did find significant increases in total DDT (??DDT) and total polychlorinated biphenyl (??PCB) post-flood (March 1999) in top predators including walleye and burbot. Significant increases were also observed in OC concentrations of zooplankton and yellow perch (> 2 fold in ??PCB, ??DDT, total chlordane (??CHL), total chlorobenzenes (??CBZ)) and walleye (1.4 fold ??PCB) over a 2-month period in the summer following the flood. Analysis of specific congener patterns over time suggest that the major changes in fish OC levels pre- and post-flood did not appear to be linked to transport of new compounds into the Lake during the flood, but to species shifts within the plankton community. Our results indicate that short-term variation (???2 months) in OC distributions within biota may be equal to or greater than those resulting from episodic events such as spring floods.

  12. Petrology and geochemistry of subbituminous coals from the Red Deer River Valley, Alberta Plains, Canada

    SciTech Connect

    Gentzis, T.; Goodarzi, F.

    1998-11-01

    Coals and associated carbonaceous strata along the Red Deer River Valley in Alberta have a wide variation in boron concentrations (10--628 ppm). Boron concentrations decrease from bottom to top of the coal-bearing succession, closely reflecting changes in depositional environment conditions. These changes range from subaquatic deposition in the delta plain area and influence of brackish waters due to a marine transgression, to deposition in areas removed from any brackish water influence. There is good agreement between boron variation and depositional environment as interpreted from regional geology. However, the relation between boron and sulfur is not clear; samples with high boron concentrations are high in sulfur while low boron samples also have high sulfur. Compared to mean concentrations in world coals, some of the highest elemental concentrations measured in coals of this study are: As (38.0 ppm), Ba (2800 ppm), Cr (91.0 ppm), Mn (232 ppm), and V (209 ppm). There is a similarity in the vertical variation of the elements Th and Hf, while bentonite layers are enriched in Ba and Sr, pointing to the presence of gorceixite. No enrichment of REEs was observed in the bentonite layers. A comparison of elemental concentration to world mean values for coals shows that the RDRV coals are elevated in As (up to 4{times}), Cr (up to 12 {times}), Mn (up to 4 {times}), Mo (up to 12 {times}), Th (up to 5 {times}), V (up to 12 {times}) and Zn (up to 5 {times}). Compared to coals from the eastern Alberta Plains of similar rank, age, and depositional environment, the RDRV coals have higher or similar concentrations of all elements of environmental significance, with the exception of Be and Pb. When compared to coals of similar rank in the western Alberta plains deposited under freshwater conditions, the RDRV coals have higher concentration of As, B, Ba, Sb, and Sr, similar concentrations of Be, Co, Cu, Mn, Pb, Se, Th, and U, and lower concentrations of Ni.

  13. Active normal faults and river damming: the importance of tectonics and climate in shaping the landscape of the southern Tibetan plateau

    NASA Astrophysics Data System (ADS)

    Kali, E.; van der Woerd, J.; Liu-Zeng, J.; LeBéon, M.; Leloup, P.-H.; Mahéo, G.; Tapponnier, P.; Thuizat, R.

    2012-04-01

    Understanding the interaction between tectonics, climate and erosion is key to unravel the geodynamic evolution of rapidly evolving landscapes. Normal faulting along the Ama Drime and fluvial incision of the Arun river are used to better describe the recent evolution of the south-central Tibetan plateau. The Arun catchment can be separated in two parts, an upper catchment characterized by the presence of abandoned shorelines testifying of the presence of a paleolake, and a lower basin with deep gorges characterized by strong fluvial incision. This geometry implies ancient damming of the Arun river in the vicinity of the Kharta normal fault. Two shorelines, the highest at 4400 m asl and a major one at 4260 m a.s.l. have been dated at about 200-250 ka and at 80-120 ka using both OSL and 10Be cosmogenic dating methods of surface and subsurface samples. In the south Kharta basin, river terraces ˜100 m above the present riverbed are offset between 10 and 15 m by one branch of the normal fault. 10Be cosmogenic nuclide exposure ages of these terraces range between 9 and 11 ka, consistent with aggradation after the Last Glacial Maximum (LGM ˜20 ka), followed by rapid incision of the Arun. A few kilometres south of Kharta, the normal fault offsets by about 30 m abandoned lateral moraines with ages ranging from 20 to 70 ka. These measurements constrain the rates of vertical displacement along the normal faults to range between 0.7 and 1.4 mm/yr since 10-15 ka. The 20-70 ka rate is less well constrained but is of the same order. To the north, the range of ages (30 to 166 ka) of a terrace offset by 150 m suggests a formation during MIS-5e, and thus a vertical slip-rate of about 1±0.5 mm/yr. 70 kilometres farther north-east, moraines are offset by 20-40 m across the Mabja west-dipping normal fault in the nothward prologation of the Kharta fault. If the moraines are correlated with the LGM advance the Mabja fault vertical slip-rate is similar to that of the Kharta fault. All these data indicate vertical rates on the order of 0.6 to 1.7 mm/yr on the North-Ssouth active faults in the Ama Drime area. The peculiar course of the Arun river meandering within gorges into the footwall of the Kharta fault downstream of the paleolake remnants indicates interaction between river damming and active normal faulting. The high lake stands may be correlated to the penultimate and last interglacial stages corresponding to enhance moisture across the Himalayas. It further suggest dam buildup during cold and dry glacial stages favoring diminished fluvial erosion and enhanced morainic debris accumulation in the gorge during continuous tectonic uplift. The end of the last lake high-stand (100-120ka) is in agreement with the highest and oldest evidence of fluvial terraces downstream of the gorge. These results show the importance of fluvial and tectonic interaction in connecting closed basins to drained valleys and thus in shaping large parts of the Tibetan plateau.

  14. Constituent loads and flow-weighted average concentrations for major subbasins of the upper Red River of the North Basin, 1997-99

    USGS Publications Warehouse

    Sether, Bradley A.; Berkas, Wayne R.; Vecchia, Aldo V.

    2004-01-01

    Data were collected at 11 water-quality sampling sites in the upper Red River of the North (Red River) Basin from May 1997 through September 1999 to describe the water-quality characteristics of the upper Red River and to estimate constituent loads and flow-weighted average concentrations for major tributaries of the Red River upstream from the bridge crossing the Red River at Perley, Minn. Samples collected from the sites were analyzed for 5-day biochemical oxygen demand, bacteria, dissolved solids, nutrients, and suspended sediment. Concentration data indicated the median concentrations for most constituents and sampling sites during the study period were less than existing North Dakota and Minnesota standards or guidelines. However, more than 25 percent of the samples for the Red River at Perley, Minn., site had fecal coliform concentrations that were greater than 200 colonies per 100 milliliters, indicating an abundance of pathogens in the upper Red River Basin. Although total nitrite plus nitrate concentrations generally increased in a downstream direction, the median concentrations for all sites were less than the North Dakota suggested guideline of 1.0 milligram per liter. Total and dissolved phosphorus concentrations also generally increased in a downstream direction, but, for those constituents, the median concentrations for most sampling sites exceeded the North Dakota suggested guideline of 0.1 milligram per liter. For dissolved solids, nutrients, and suspended sediments, a relation between constituent concentration and streamflow was determined using the data collected during the study period. The relation was determined by a multiple regression model in which concentration was the dependent variable and streamflow was the primary explanatory variable. The regression model was used to compute unbiased estimates of annual loads for each constituent and for each of eight primary water-quality sampling sites and to compute the degree of uncertainty associated with each estimated annual load. The estimated annual loads for the eight primary sites then were used to estimate annual loads for five intervening reaches in the study area. Results were used as a screening tool to identify which subbasins contributed a disproportionate amount of pollutants to the Red River. To compare the relative water quality of the different subbasins, an estimated flow-weighted average (FWA) concentration was computed from the estimated average annual load and the average annual streamflow for each subbasin. The 5-day biochemical oxygen demands in the upper Red River Basin were fairly small, and medians ranged from 1 to 3 milligrams per liter. The largest estimated FWA concentration for dissolved solids (about 630 milligrams per liter) was for the Bois de Sioux River near Doran, Minn., site. The Otter Tail River above Breckenridge, Minn., site had the smallest estimated FWA concentration (about 240 milligrams per liter). The estimated FWA concentrations for dissolved solids for the main-stem sites ranged from about 300 to 500 milligrams per liter and generally increased in a downstream direction. The estimated FWA concentrations for total nitrite plus nitrate for the main-stem sites increased from about 0.2 milligram per liter for the Red River below Wahpeton, N. Dak., site to about 0.9 milligram per liter for the Red River at Perley, Minn., site. Much of the increase probably resulted from flows from the tributary sites and intervening reaches, excluding the Otter Tail River above Breckenridge, Minn., site. However, uncertainty in the estimated concentrations prevented any reliable conclusions regarding which sites or reaches contributed most to the increase. The estimated FWA concentrations for total ammonia for the main-stem sites increased from about 0.05 milligram per liter for the Red River above Fargo, N. Dak., site to about 0.15 milligram per liter for the Red River near Harwood, N. Dak., site. T

  15. Change in Sahelian Rivers hydrograph: The case of recent red floods of the Niger River in the Niamey region

    NASA Astrophysics Data System (ADS)

    Descroix, Luc; Genthon, Pierre; Amogu, Okechukwu; Rajot, Jean-Louis; Sighomnou, Daniel; Vauclin, Michel

    2012-12-01

    Changes in the hydrological regime of Sahelian Rivers are considered based upon the example of the Middle Niger River and its exceptional flood in 2010 near the city of Niamey. It is shown that rainfall in 2010 was only average with respect to the long term record, with neither the monthly rainfall distribution in terms of the amount of rainfall nor the distribution of rainy events changing significantly in the last few decades. Particularly, no increase in the number of extreme rainfall events is observed. In spite of this, the Niger River's right bank tributaries have shown a sharp increase in runoff since the 1970s, which is still ongoing, and has resulted in a modification of the Niger River's regime from a single hydrograph to a two flood hydrograph, the local flood, occurring during the rainy season being the more pronounced one. This modification is likely due to an increase of bare soils and crusted soil areas as a consequence of human pressure, resulting mostly from the spatial extension of crop areas and the shortening of fallow periods. Changes in connectivity of the river networks on both banks of the Niger such as endorheism bursting events also caused an increase in the contributing basin area. Policy makers should be alerted to the effects of intensive cropping, land clearing and overgrazing in some areas, on the hydrological regimes of Sahelian Rivers.

  16. Seasonal variability of faecal indicator bacteria numbers and die-off rates in the Red River basin, North Viet Nam

    PubMed Central

    Nguyen, Huong Thi Mai; Le, Quynh Thi Phuong; Garnier, J.; Janeau, J.-L.; Rochelle-Newall, E.

    2016-01-01

    The Red River is the second largest river in Viet Nam and constitutes the main water source for a large percentage of the population of North Viet Nam. Here we present the results of an annual survey of Escherichia coli (EC) and Total Coliforms (TC) in the Red River basin, North Viet Nam. The objective of this work was to obtain information on faecal indicator bacteria (FIB) numbers over an annual cycle and, secondly, to determine the die-off rates of these bacterial indicators. Monthly observations at 10 stations from July 2013–June 2014 showed that TC and EC reached as high as 39100 cfu (colony forming units) 100 ml−1 and 15300 colonies 100 ml−1, respectively. We observed a significant seasonal difference for TC (p < 0.05) with numbers being higher during the wet season. In contrast, no significant seasonal difference was found for EC. The FIB die-off rates ranged from 0.01 d−1 to a maximum of 1.13 d−1 for EC and from 0.17 d−1 to 1.33 d−1 for TC. Die-off rates were significantly higher for free bacteria than for total (free + particle attached) bacteria, suggesting that particle attachment provided a certain level of protection to FIB in this system. PMID:26869451

  17. Seasonal variability of faecal indicator bacteria numbers and die-off rates in the Red River basin, North Viet Nam.

    PubMed

    Nguyen, Huong Thi Mai; Le, Quynh Thi Phuong; Garnier, J; Janeau, J-L; Rochelle-Newall, E

    2016-01-01

    The Red River is the second largest river in Viet Nam and constitutes the main water source for a large percentage of the population of North Viet Nam. Here we present the results of an annual survey of Escherichia coli (EC) and Total Coliforms (TC) in the Red River basin, North Viet Nam. The objective of this work was to obtain information on faecal indicator bacteria (FIB) numbers over an annual cycle and, secondly, to determine the die-off rates of these bacterial indicators. Monthly observations at 10 stations from July 2013-June 2014 showed that TC and EC reached as high as 39100 cfu (colony forming units) 100?ml(-1) and 15300 colonies 100?ml(-1), respectively. We observed a significant seasonal difference for TC (p?

  18. Systematic deflection and offset of the Yangtze River drainage system along the strike-slip Ganzi-Yushu-Xianshuihe Fault Zone, Tibetan Plateau

    NASA Astrophysics Data System (ADS)

    Yan, Bing; Lin, Aiming

    2015-07-01

    The Ganzi-Yushu-Xianshuihe Fault Zone (GYXFZ) is a typical active strike-slip fault that has triggered many large historic earthquakes, including the 2010 Mw 6.9 Yushu earthquake in the central Tibetan Plateau. This fault zone extends for ca. 800 km from the central Tibetan Plateau to its southeastern margin and varies in trend from WNW-ESE in the northwestern segment of the fault zone to NNW-SSE in the southeastern segment, having the geometry of an arc projecting northeastwards. In this study, we present evidence for the systematical sinistral deflection and/or offset of the Yangtze River and its branch stream channels and valleys along the GYXFZ. Topographic analysis of three-dimensional (3D) perspective images constructed using digital elevation model (DEM) data, 0.5 m-resolution WorldView and GeoEye images, and 15 m-resolution Landsat-Enhanced Thematic Mapper (ETM+) images, together with analysis of geological structures, reveals the following: (i) the main river channels and valleys of the Yangtze River drainage system show systematic sinistral deflections and/or offsets along the GYXFZ; (ii) various amounts of sinistral offset have accumulated on the tributary stream channels, valleys, and gullies of the Yangtze River along the fault, with a linear relation, D = aL, between the upstream length L from the deflected point and the offset amount D with a certain coefficient a; (iii) the maximum amount of sinistral offset is up to ca. 60 km, which was accumulated in the past 13-5 Ma; and (iv) the long-term average strike-slip rate is ca. 4.6-12 mm/year. Geological and geomorphic evidence, combined with geophysical data, demonstrates that the GYXFZ is currently active as one of the major seismogenic faults in the Tibetan Plateau, dominated by left-lateral strike-slip motion. Our findings supply important evidence for the tectonic evolution of strike-slip faults in the Tibetan Plateau since the Eurasia-India continental collision.

  19. Arsenic in groundwater of the Red River floodplain, Vietnam: Controlling geochemical processes and reactive transport modeling

    NASA Astrophysics Data System (ADS)

    Postma, Dieke; Larsen, Flemming; Minh Hue, Nguyen Thi; Duc, Mai Thanh; Viet, Pham Hung; Nhan, Pham Quy; Jessen, Søren

    2007-11-01

    The mobilization of arsenic (As) to the groundwater was studied in a shallow Holocene aquifer on the Red River flood plain near Hanoi, Vietnam. The groundwater chemistry was investigated in a transect of 100 piezometers. Results show an anoxic aquifer featuring organic carbon decomposition with redox zonation dominated by the reduction of Fe-oxides and methanogenesis. Enhanced PCO 2 pressure causes carbonate dissolution to take place but mainly in the soil and unsaturated zone. The concentration of As increases over depth to a concentration of up to 550 μg/L. Most As is present as As(III) but some As(V) is always found. Arsenic correlates well with NH 4, relating its release to organic matter decomposition and the source of As appears to be the Fe-oxides being reduced. Part of the produced Fe(II) is apparently reprecipitated as siderite containing less As. Results from sediment extraction indicate most As to be related to the Fe-oxide fractions. The measured amount of sorbed As is low. In agreement, speciation calculations for a Fe-oxide surface suggest As(III) to constitute only 3% of the surface sites while the remainder is occupied by carbonate and silica species. The evolution in water chemistry over depth is homogeneous and a reactive transport model was constructed to quantify the geochemical processes along the vertical groundwater flow component. A redox zonation model was constructed using the partial equilibrium approach with organic carbon degradation in the sediment as the only rate controlling parameter. Apart from the upper meter a constant degradation rate of 0.15 C mmol/L/yr could explain the redox zonation throughout the aquifer. Modeling also indicates that the Fe-oxide being reduced is of a stable type like goethite or hematite. Arsenic is contained in the Fe-oxides and is first released during their dissolution. Our model further suggests that part of the released As is adsorbed on the surface of the remaining Fe-oxides and in this way may be retarded.

  20. Impact of the Hoa Binh dam (Vietnam) on water and sediment budgets in the Red River basin and delta

    NASA Astrophysics Data System (ADS)

    Vinh, V. D.; Ouillon, S.; Thanh, T. D.; Chu, L. V.

    2014-10-01

    The Hoa Binh dam (HBD), located on a tributary of the Red River in Vietnam, has a capacity of 9.45 × 109 m3 and was commissioned in December 1988. Although it is important for flood prevention, electricity production and irrigation in northern Vietnam, the Hoa Binh dam has also highly influenced the suspended sediment distribution in the lower Red River basin, in the delta and in the coastal zone. Its impact was analysed from a 50-year data set of water discharge and suspended sediment concentration (1960-2010), and the distribution of water and sediment across the nine mouths of the delta was simulated using the MIKE11 numerical model before and after the dam settlement. Although water discharge at the delta inlet decreased by only 9%, the yearly suspended sediment flux dropped, on average, by 61% at Son Tay near Hanoi (from 119 to 46 × 106 t yr-1). Along the coast, reduced sedimentation rates are coincident with the lower sediment delivery observed since the impoundment of the Hoa Binh dam. Water regulation has led to decreased water discharge in the wet season (-14% in the Red River at Son Tay) and increased water discharge in the dry season (+12% at the same station). The ratios of water and suspended sediment flows, as compared to the total flows in the nine mouths, increased in the northern and southern estuaries and decreased in the central, main Ba Lat mouth. The increasing volume of dredged sediments in the Haiphong harbour is evidence of the silting up of the northern estuary of Cam-Bach Dang. The effect of tidal pumping on enhanced flow occurring in the dry season and resulting from changed water regulation is discussed as a possible cause of the enhanced siltation of the estuary after Hoa Binh dam impoundment.

  1. 77 FR 27118 - Safety Zone; Rocketts Red Glare Fireworks, Ancarrows Landing Park, James River, Richmond, VA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-09

    ..., VA in the Federal Register (76 FR 13525). We ] received no comments on the proposed rule. No public... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Rocketts Red Glare Fireworks, Ancarrows... in Richmond, VA in support of the Rocketts Red Glare Fireworks event. This action is necessary...

  2. Trace metal and metalloid levels in surface water of Marcal River before and after the Ajka red mud spill, Hungary.

    PubMed

    Nagy, Andrea Szabó; Szabó, János; Vass, István

    2013-11-01

    The aim of this study was to compare and assess the dissolved concentrations of trace elements (As, Zn, Hg, Cd, Cr, Ni, Pb and Cu) in surface water of Marcal River before and after the red mud spill that occurred in Ajka, western Hungary, in October 2010. The caustic sludge flooded the surrounding settlements and polluted the nearby Torna Creek, which flows through the Marcal and Raba rivers into the Danube. A total of 92 surface water samples were collected from the Marcal River in the period of 2007-2012 and analysed for dissolved trace metal(loid)s by atomic absorption spectroscopy method. After the spill, the water management authority initially focused on acid dosing of surface waters to lower pH and was effective in lowering both pH and metal(loid) concentrations. Among the dissolved trace metal(loid)s, arsenic and nickel levels were moderately higher in the Marcal River 2 years since the spill compared to that observed in the pre-disaster period. The concentrations of dissolved trace metal(loid)s did not exceed the European water quality standards and the US Environmental Protection Agency aquatic life criteria values (excluding one sample for cadmium). PMID:23975713

  3. Bromide, Chloride, and Sulfate Concentrations and Loads at U.S. Geological Survey Streamflow-Gaging Stations 07331600 Red River at Denison Dam, 07335500 Red River at Arthur City, and 07336820 Red River near DeKalb, Texas, 2007-09

    USGS Publications Warehouse

    Baldys, Stanley; Churchill, Christopher J.; Mobley, Craig A.; Coffman, David K.

    2010-01-01

    The U.S. Geological Survey, in cooperation with the City of Dallas Water Utilities Division, did a study to characterize bromide, chloride, and sulfate concentrations and loads at three U.S. Geological Survey streamflow-gaging stations on the reach of the Red River from Denison Dam, which impounds Lake Texoma, to the U.S. Highway 259 bridge near DeKalb, Texas. Bromide, chloride, and sulfate concentrations and loads were computed for streamflow-gaging stations on the study reach of the Red River. Continuous streamflow and specific conductance data and discrete samples for bromide, chloride, sulfate, and specific conductance were collected at three main-stem streamflow-gaging stations on the Red River: 07331600 Red River at Denison Dam near Denison, Texas (Denison Dam gage), 07335500 Red River at Arthur City, Texas (Arthur City gage), and 07336820 Red River near DeKalb, Texas (DeKalb gage). At each of these streamflow-gaging stations, discrete water-quality data were collected during January 2007-February 2009; continuous water-quality data were collected during March 2007-February 2009. Two periods of high flow resulted from floods during the study; floods during June-July 2007 resulted in elevated flow during June-September 2007 and smaller floods during March-April 2008 resulted in elevated flow during March-April 2008. Bromide, chloride, and sulfate concentrations in samples collected at the three gages decreased downstream. Median bromide concentrations ranged from 0.32 milligram per liter at the Denison Dam gage to 0.19 milligram per liter at the DeKalb gage. Median chloride concentrations ranged from 176 milligrams per liter at the Denison Dam gage to 108 milligrams per liter at the DeKalb gage, less than the 300-milligrams per liter secondary maximum contaminant level established by the Texas Commission on Environmental Quality. Median sulfate concentrations ranged from 213 milligrams per liter at the Denison Dam gage to 117 milligrams per liter at the DeKalb gage, also less than the 300-milligrams per liter secondary maximum contaminant level. Kruskal-Wallis analyses indicated statistically significant differences among bromide, chloride, and sulfate concentrations at the three gages. Regression equations to estimate bromide, chloride, and sulfate loads were developed for each of the three gages. The largest loads were estimated for a period of relatively large streamflow, June-September 2007, when about 50 percent of the load for the study period occurred at each gage. Adjusted R-squared values were largest for regression equations for the DeKalb gage, ranging from .957 for sulfate to .976 for chloride. Adjusted R-squared values for all regression equations developed to estimate loads of bromide, chloride, and sulfate at the three gages were .899 or larger.

  4. General weather conditions and precipitation contributing to the 2011 flooding in the Mississippi River and Red River of the North Basins, December 2010 through July 2011: Chapter B in 2011 floods of the central United States

    USGS Publications Warehouse

    Vining, Kevin C.; Chase, Katherine J.; Loss, Gina R.

    2013-01-01

    Excessive precipitation produced severe flooding in the Mississippi River and Red River of the North Basins during spring and summer 2011. The 2011 flooding was caused by weather conditions that were affected in part by a La Niña climate pattern. During the 2010–11 climatological winter (December 2010–February 2011), several low pressure troughs from the Rocky Mountains into the Ohio River subbasin produced large amounts of precipitation. Precipitation was above normal to record amounts in parts of the Missouri River, Red River of the North, and upper Mississippi River subbasins, and mostly normal to below normal in the Ohio River and lower Mississippi River subbasins. During the 2011 climatological spring (March–May 2011), a large low pressure trough over the continental States and a high pressure ridge centered in the vicinity of the Gulf of Mexico combined to produce storms with copious precipitation along frontal boundaries across the Central States. Rain totals recorded during the April 18–28, 2011, precipitation event were more than 8 inches at several locations, while an impressive total of 16.15 inches was recorded at Cape Girardeau, Missouri. Several locations in the Missouri River subbasin had rainfall totals that were nearly one-third to one-half of their 1971–2000 normal annual amounts during a May 16–31, 2011, precipitation event. During June and July, thunderstorm development along frontal boundaries resulted in areas of heavy rain across the Missouri River, Red River of the North, and upper Mississippi River subbasins, while rainfall in the lower Mississippi River subbasin was mostly below normal.

  5. Red shiner invasion and hybridization with blacktail shiner in the upper Coosa River, USA

    EPA Science Inventory

    Human disturbance increases the invasibility of lotic ecosystems and the likelihood of hybridization between invasive and native species. We investigated whether disturbance has contributed to the invasion of red shiner (Cyprinella lutrensis) and their hybridization with native b...

  6. Oscillating brittle and viscous behavior through the earthquake cycle in the Red River Shear Zone: Monitoring flips between reaction and textural softening and hardening

    NASA Astrophysics Data System (ADS)

    Wintsch, Robert P.; Yeh, Meng-Wan

    2013-03-01

    Microstructures associated with cataclasites and mylonites in the Red River shear zone in the Diancang Shan block, Yunnan Province, China show evidence for both reaction hardening and softening at lower greenschist facies metamorphic conditions. The earliest fault-rocks derived from Triassic porphyritic orthogneiss protoliths are cataclasites. Brittle fractures and crushed grains are cemented by newly precipitated quartz. These cataclasites are subsequently overprinted by mylonitic fabrics. Truncations and embayments of relic feldspars and biotites show that these protolith minerals have been dissolved and incompletely replaced by muscovite, chlorite, and quartz. Both K-feldspar and plagioclase porphyroclasts are truncated by muscovite alone, suggesting locally metasomatic reactions of the form: 3K-feldspar + 2H+ = muscovite + 6SiO2(aq) + 2K+. Such reactions produce muscovite folia and fish, and quartz bands and ribbons. Muscovite and quartz are much weaker than the reactant feldspars and these reactions result in reaction softening. Moreover, the muscovite tends to align in contiguous bands that constitute textural softening. These mineral and textural modifications occurred at constant temperature and drove the transition from brittle to viscous deformation and the shift in deformation mechanism from cataclasis to dissolution-precipitation and reaction creep. These mylonitic rocks so produced are cut by K-feldspar veins that interrupt the mylonitic fabric. The veins add K-feldspar to the assemblage and these structures constitute both reaction and textural hardening. Finally these veins are boudinaged by continued viscous deformation in the mylonitic matrix, thus defining a late ductile strain event. Together these overprinting textures and microstructures demonstrate several oscillations between brittle and viscous deformation, all at lower greenschist facies conditions where only frictional behavior is predicted by experiments. The overlap of the depths of greenschist facies conditions with the base of the crustal seismic zone suggests that the implied oscillations in strain rate may have been related to the earthquake cycle.

  7. Metal accumulation in eggs of the red-eared slider (Trachemys scripta elegans) in the Lower Illinois River.

    PubMed

    Tryfonas, Anna E; Tucker, John K; Brunkow, Paul E; Johnson, Kevin A; Hussein, Hussein S; Lin, Zhi-Qing

    2006-03-01

    The Illinois River is a highly utilized navigable waterway in the US Midwest, and has historically been contaminated with metal toxicants from various industrial and municipal pollution sources. Little information on metal contamination is available in the Lower Illinois River, and in particular, in the habitat of the red-eared slider (Trachemys scripta elegans) at the southern end of the river near Grafton, IL. This study was conducted to determine current levels of metal contamination in water, sediment, soil, and plants in the habitat, as well as to reveal temporal and spatial variations of metal accumulation in eggs of the red-eared slider. Aluminum, Cd, Cr, Cu, Mn, Ni, Pb, V, Sn, and Zn were analyzed by inductively-coupled plasma spectroscopy. High concentrations of metals were observed in lake sediment, compared with the concentrations in water, soil, and plant tissues. Sediment Ni concentrations (mg kg(-1)) varied from 66 to 95 and Sn from 1100 to 1600. Five detectable metals in egg content were Zn (24.2 +/- 13), Al (2.2 +/- 1.2), Sn (1.8 +/- 1.1), Mn (1.1 +/- 0.6), and Cu (0.9 +/- 0.5); nine detectable metals in egg shell were Zn (6.8 +/- 3.9), Sn (3.7 +/- 3.1), Cu (1.9 +/- 1.3), Cr (1.6 +/- 1.5), V (1.6 +/- 1.4), Pb (1.3 +/- 0.7), Ni (1.3 +/- 0.9), Mn (1.0 +/- 0.8), and Cd (0.16 +/- 0.11). Zinc accumulation in egg content was significantly correlated with Zn in egg shell (r = 0.445, P < 0.002, n = 42). While significant spatial variation was observed in egg shell, metal accumulation in eggs (content and shell) collected from the same ground of turtles consecutively for 4 years did not show a significant temporal change. PMID:16216308

  8. Impact of the Hoa Binh Dam (Vietnam) on water and sediment budgets in the Red River basin and delta

    NASA Astrophysics Data System (ADS)

    Vu, D. V.; Ouillon, S.; Tran, D. T.; La, V. C.

    2014-01-01

    The Hoa Binh Dam, located on a tributary of the Red River in Vietnam, has a capacity of 9.45 × 109 m3 and was commissioned in December 1988. Although being important for flood prevention, electricity production, and irrigation in northern Vietnam, the Hoa Binh Dam has also highly influenced the suspended sediment distribution in the lower Red River basin, in the delta and in the coastal zone. Its impact was analysed from 50 yr dataset of water discharge and suspended sediment concentration (1960-2010) and the distribution of water and sediment across the nine mouths of the delta was calculated using the MIKE 11 numerical model before and after the dam settlement. Although water discharge at the delta inlet decreased by only 8.8%, the yearly suspended sediment flux dropped, on average from 119 to 43 × 106 t yr-1 at Son Tay near Hanoi, and from 85 to 35 × 106 t yr-1 in the river mouths. Water regulation has led to decreased water discharge in the wet season and increased water discharge in the dry season. Suspended sediment discharge proportionally increased in northern and southern estuaries and decreased through the main and central Ba Lat mouth. Tidal pumping, which causes a net sediment flux from the coast to the estuary at low discharge, is high in the northern delta, as a consequence of the high tidal range (up to 4.5 m in spring tide; diurnal tide). The shifts in the dynamic and characteristics of the turbidity maximum zone in the Cam-Bach Dang estuary are probably the cause of the enhanced sediment deposition in the Haiphong harbor. Along the coast, the reduced sedimentation rates are coincident with the lower sediment delivery that has been observed since the impoundment of the Hoa Binh Dam.

  9. Variation of the fractal dimension anisotropy of two major Cenozoic normal fault systems over space and time around the Snake River Plain, Idaho and SW Montana

    NASA Astrophysics Data System (ADS)

    Davarpanah, A.; Babaie, H. A.

    2012-12-01

    The interaction of the thermally induced stress field of the Yellowstone hotspot (YHS) with existing Basin and Range (BR) fault blocks, over the past 17 m.y., has produced a new, spatially and temporally variable system of normal faults around the Snake River Plain (SRP) in Idaho and Wyoming-Montana area. Data about the trace of these new cross faults (CF) and older BR normal faults were acquired from a combination of satellite imageries, DEM, and USGS geological maps and databases at scales of 1:24,000, 1:100,000, 1:250,000, 1:1000, 000, and 1:2,500, 000, and classified based on their azimuth in ArcGIS 10. The box-counting fractal dimension (Db) of the BR fault traces, determined applying the Benoit software, and the anisotropy intensity (ellipticity) of the fractal dimensions, measured with the modified Cantor dust method applying the AMOCADO software, were measured in two large spatial domains (I and II). The Db and anisotropy of the cross faults were studied in five temporal domains (T1-T5) classified based on the geologic age of successive eruptive centers (12 Ma to recent) of the YHS along the eastern SRP. The fractal anisotropy of the CF system in each temporal domain was also spatially determined in the southern part (domain S1), central part (domain S2), and northern part (domain S3) of the SRP. Line (fault trace) density maps for the BR and CF polylines reveal a higher linear density (trace length per unit area) for the BR traces in the spatial domain I, and a higher linear density of the CF traces around the present Yellowstone National Park (S1T5) where most of the seismically active faults are located. Our spatio-temporal analysis reveals that the fractal dimension of the BR system in domain I (Db=1.423) is greater than that in domain II (Db=1.307). It also shows that the anisotropy of the fractal dimension in domain I is less eccentric (axial ratio: 1.242) than that in domain II (1.355), probably reflecting the greater variation in the trend of the BR system in domain I. The CF system in the S1T5 domain has the highest fractal dimension (Db=1.37) and the lowest anisotropy eccentricity (1.23) among the five temporal domains. These values positively correlate with the observed maxima on the fault trace density maps. The major axis of the anisotropy ellipses is consistently perpendicular to the average trend of the normal fault system in each domain, and therefore approximates the orientation of extension for normal faulting in each domain. This fact gives a NE-SW and NW-SE extension direction for the BR system in domains I and II, respectively. The observed NE-SW orientation of the major axes of the anisotropy ellipses in the youngest T4 and T5 temporal domains, oriented perpendicular to the mean trend of the normal faults in the these domains, suggests extension along the NE-SW direction for cross faulting in these areas. The spatial trajectories (form lines) of the minor axes of the anisotropy ellipses, and the mean trend of fault traces in the T4 and T5 temporal domains, define a large parabolic pattern about the axis of the eastern SRP, with its apex at the Yellowstone plateau.

  10. Establishment of a viable population of red-cockaded woodpeckers at the Savannah River Site. Annual report, FY1992

    SciTech Connect

    Laves, K.S.

    1992-09-11

    The Southeastern Forest Experiment Station (SEFES) began research on the red-cockaded woodpecker (RCW) on the Savannah River Site (SRS) in 1985 with the objective of restoring a viable population. This Project is conducted in cooperation with the Department of Energy, the Savannah River Forest Station (SRFS) and the Savannah River Ecology Laboratory. The program has consisted of two phases. The stabilization phase (1985--1987) focused on preventing the immediate extirpation of the RCW population. During this phase the number of breeding pairs of RCWs increased from one to three, and the total population increased from five to 14 birds. We are currently in the expansion phase (1987--present). To facilitate the population expansion of the RCW at SRS, SEFES and SRFS have implemented numerous research and management activities. These include: control of mid-story vegetation to improve habitat suitability, installation of artificial cavities for RCWS, translocations of RCWs within the SRS and from other populations, maintenance of cavities by installing metal restrictors to discourage cavity competition, and generic research to ascertain the degree of relatedness between individuals and populations.

  11. Establishment of a viable population of red-cockaded woodpeckers at the Savannah River Site. Annual report, FY 1990

    SciTech Connect

    Allen, D.H.

    1990-12-31

    In 1985 the Southeastern Forest Experiment Station (SEFES) in cooperation with the Department of Energy, the Savannah River Forest Station (SRFS) and the Savannah River Ecology Laboratory (SREL) initiated a research/management program to restore a viable population of red-cockaded woodpeckers (RCW) to the Savannah River Site (SRS). We managed to stabilize the population in the first couple of years through an intensive flying squirrel removal project as well as augmentation of female RCW`s to the SRS population. We are now in the expansion phase of the project. In 1990 we have focused our efforts on: (1) developing a cavity excavation method and excavating cavities in suitable habitat; (2) flying squirrel control; (3) translocation of RCW`s; (4) monitoring clan composition and reproduction; (5) identification of old-growth stands with the potential of providing new nesting habitat to support population expansion; and (6) surveying lands near SRS where RCW`s were thought to exist. This report summarizes activities for FY 1990 and plans for FY 1991.

  12. Sediment concentrations, loads, and particle-size distributions in the Red River of the North and selected tributaries near Fargo, North Dakota, during the 2011 spring high-flow event

    USGS Publications Warehouse

    Galloway, Joel M.; Blanchard, Robert A.; Ellison, Christopher A.

    2011-01-01

    Most of the bedload samples had particle sizes in the 0.5 to 1 millimeter and 0.25 to 0.5 millimeter ranges from the Maple River, Wild Rice River, Rush River, Buffalo River, and Red River sites. The Rush and Lower Branch Rush Rivers also had a greater portion of larger particle sizes in the 1 to 2 millimeter range. The Sheyenne River sites had a greater portion of smaller particle sizes in the bedload in the 0.125 to 0.5 millimeter range compared to the other sites. The bed material in samples collected during the 2011 spring high-flow event demonstrated a wider distribution of particle sizes than were observed in the bedload; the coarsest material was found at the Red River near Christine and the Lower Branch Rush River and the finest material at the Sheyenne River sites.

  13. Gastrointestinal parasites of critically endangered primates endemic to Tana River, Kenya: Tana River red colobus (Procolobus rufomitratus) and crested mangabey (Cercocebus galeritus).

    PubMed

    Mbora, David N M; Munene, Elephas

    2006-10-01

    We conducted fecal egg counts of gastrointestinal parasites of 2 critically endangered primates endemic to the forest of Tana River, Kenya. We aimed to use the fecal egg counts as proxies to quantify the prevalence of gastrointestinal parasites between the 2 primates. The Tana River red colobus (Procolobus rufomitratus) and crested mangabey (Cercocebus galeritus) are of similar body size, but their behavioral ecology is very different. We predicted that mangabeys would have a higher prevalence of parasites because they are mostly terrestrial omnivores, live in larger social groups, and therefore range widely. We detected 10 nematodes and 3 protozoans in mangabeys and 7 nematodes and 2 protozoans in colobus. We detected a higher number of different parasite species in individual mangabeys, and 4 of the 5 nematodes requiring intermediate hosts were found in mangabeys. The overall prevalence of parasites was higher for mangabeys, but this difference was not statistically significant. For colobus, we found a trend whereby the number of different parasite species in individual monkeys was higher in males and in lactating females. However, there was no difference in the prevalence of parasites between the sexes or between lactating and nonlactating females. PMID:17152930

  14. Coupling legacy geomorphic surface facies to riparian vegetation: Assessing red cedar invasion along the Missouri River downstream of Gavins Point dam, South Dakota

    NASA Astrophysics Data System (ADS)

    Greene, Samantha L.; Knox, James C.

    2014-01-01

    Floods increase fluvial complexity by eroding established surfaces and creating new alluvial surfaces. As dams regulate channel flow, fluvial complexity often decreases and the hydro-eco-geomorphology of the riparian habitat changes. Along the Missouri River, flow regulation resulted in channel incision of 1-3 m within the study area and disconnected the pre-dam floodplain from the channel. Evidence of fluvial complexity along the pre-dam Missouri River floodplain can be observed through the diverse depositional environments represented by areas of varying soil texture. This study evaluates the role of flow regulation and depositional environment along the Missouri River in the riparian invasion of red cedar downstream of Gavins Point dam, the final dam on the Missouri River. We determine whether invasion began before or after flow regulation, determine patterns of invasion using Bayesian t-tests, and construct a Bayesian multivariate linear model of invaded surfaces. We surveyed 59 plots from 14 riparian cottonwood stands for tree age, plot composition, plot stem density, and soil texture. Red cedars existed along the floodplain prior to regulation, but at a much lower density than today. We found 2 out of 565 red cedars established prior to regulation. Our interpretation of depositional environments shows that the coarser, sandy soils reflect higher energy depositional pre-dam surfaces that were geomorphically active islands and point bars prior to flow regulation and channel incision. The finer, clayey soils represent lower energy depositional pre-dam surfaces, such as swales or oxbow depressions. When determining patterns of invasion for use in a predictive statistical model, we found that red cedar primarily establishes on the higher energy depositional pre-dam surfaces. In addition, as cottonwood age and density decrease, red cedar density tends to increase. Our findings indicate that flow regulation caused hydrogeomorphic changes within the study area that permitted red cedar invasion of the riparian habitat and that the type of depositional environment partially determines where along the riparian landscape red cedar invades.

  15. Pervasive post-Eocene faulting and folding in unconsolidated sediments of the Mississippi River, Central U.S. as imaged by high-resolution CHIRP seismic data

    NASA Astrophysics Data System (ADS)

    Fave, X. J.; Magnani, M.; Waldron, B. A.; McIntosh, K. D.; Saustrup, S.; Guo, L.

    2010-12-01

    Despite being located in the stable continental interior of the North American plate, in 1811-1812 the New Madrid Seismic Zone (NMSZ) experienced among the largest magnitude historical earthquakes that ever occurred in the U.S. Paleoseismological evidence shows that large earthquakes have been occurring every 500 yr in the region for the past few thousand years, and historical and instrumental seismicity demonstrate that the NMSZ fault system is actively deforming today. By contrast, motion rates emerging from almost twenty years of geodetic observations substantiate a very slow rate of deformation across the NMSZ faults, suggesting that present velocities are not representative of the long-term deformation rate of the NMSZ fault system, and that deformation has likely been accommodated along structures additional to the NMSZ. In the summer of 2010, a high-resolution marine seismic reflection survey was carried out along the Mississippi River as part of a multi-year cooperative effort to investigate the spatial and temporal distribution of deformation in the Mississippi Embayment. Coincident to the seismic reflection profile, the survey also acquired ~300 km of CHIRP (Edgetech SB-512i) data from Cape Girardeau, MO to Caruthersville, MO. The CHIRP used a 0.7-1.2 kHz source pulse and recorded to a depth of 5-50 m sub-bottom. Here we present the preliminary interpretation of part of the CHIRP profile along the Mississippi River north of Hickman, KY, where the survey imaged a highly reflective sedimentary package down to a depth of ~50 m. The sedimentary sequence is about 20 m thick and appears to be bounded at the top and at the bottom by angular unconformities. The package is mildly folded and pervasively faulted, in some cases by extensional faults that exhibit up to 2 m of displacement and that reach the riverbed. Based on exposure of Eocene deposits 7 km to the east of the study area, and on the correlation of electric and gamma logs of nearby oil, gas and water wells, projected from 12 km to the west and which penetrated the Eocene units at a depth of 67 m, we determined that the reflective package corresponds to one of the elements of the Jackson Fm, (i.e. the top of the Eocene and of the Tertiary sequences), sealed at the top by the basal unconformity of the Mississippi River Quaternary alluvium and at the bottom by the Claiborne Group deposits. ¬

  16. Long-term monitoring (1960-2008) of the river-sediment transport in the Red River Watershed (Vietnam): temporal variability and dam-reservoir impact.

    PubMed

    Dang, Thi Ha; Coynel, Alexandra; Orange, Didier; Blanc, Gérard; Etcheber, Henri; Le, Lan Anh

    2010-09-15

    The Red River (China/Vietnam, A=155,000 km(2)) is a typical humid tropics river originating from the mountainous area of Yunnan Province in China. Based on information on daily discharge (Q) and suspended particulate matter (SPM) concentration between 1960-2008 for the SonTay gauging station (outlet of the River and entry to the Delta) provided by the National Institute IMHE-MONRE, the mean annual SPM flux was estimated at 90 Mt/yr, corresponding to a sediment yield of 600 t/km(2)/yr. The temporal variability of annual SPM fluxes (ranging from 24 to 200 Mt/yr) is strongly related to the interannual hydrological conditions. However, some years of high water flow were not associated with high sediment fluxes, especially after 1989 when the HoaBinh dam came into operation. Therefore, the median discharge pre- (3389 m(3)/s) and post 1989 (3495 m(3)/s) are similar indicating there was little or no change between both periods. Sediment rating curves (power law-type; SPM=aQ(b)) were fitted for both periods (1960-1989; 1990-2008). The analysis of the pre- and post-1989 sediment rating parameters (a, b) suggests a downshift of b-parameter values after 1989, attributed to a decrease of the sediment supply due to the commissioning of the HoaBinh dam. A single sediment rating curve derived from 1960-1989 data was used to simulate the annual variability of former sediment delivery, generating excellent cumulative flux estimates (error ~1%). In contrast, applying the same rating curve to the 1990-2008 data resulted in systematic and substantial (up to 109%) overestimation. This suggests that the HoaBinh dam reduces annual SPM delivery to the delta by half, implying important metal/metalloid storage behind the HoaBinh dam. PMID:20673966

  17. Streamflow characteristics of streams in the Upper Red River of the North basin, North Dakota, Minnesota, and South Dakota

    USGS Publications Warehouse

    Wiche, G.J.; Williams-Sether, Tara

    1997-01-01

    Statistical summaries of streamflow data for all active and inactive gaging stations for the Red River Basin upstream of and including Halstad, Minnesota, are presented in this report. The summaries for each streamflow-gaging station include (1) manuscript (station description), (2) graph of the annual mean discharge for the period of record, (3) statistics of monthly and annual mean discharges, (4) graph of the annual flow duration, (5) monthly and annual flow duration, (6) probability of annual high discharges, (7) probability of annual low discharges, (8) probability of seasonal low discharges, (9) annual peak discharge and corresponding gage height for the period of record, and (10) monthly and annual mean discharges for the period of record.

  18. Reservoir characterization of the Ordovician Red River Formation in southwest Williston Basin Bowman County, ND and Harding County, SD

    SciTech Connect

    Sippel, M.A.; Luff, K.D.; Hendricks, M.L.; Eby, D.E.

    1998-07-01

    This topical report is a compilation of characterizations by different disciplines of the Red River Formation in the southwest portion of the Williston Basin and the oil reservoirs which it contains in an area which straddles the state line between North Dakota and South Dakota. Goals of the report are to increase understanding of the reservoir rocks, oil-in-place, heterogeneity, and methods for improved recovery. The report is divided by discipline into five major sections: (1) geology, (2) petrography-petrophysical, (3) engineering, (4) case studies and (5) geophysical. Interwoven in these sections are results from demonstration wells which were drilled or selected for special testing to evaluate important concepts for field development and enhanced recovery. The Red River study area has been successfully explored with two-dimensional (2D) seismic. Improved reservoir characterization utilizing 3-dimensional (3D) and has been investigated for identification of structural and stratigraphic reservoir compartments. These seismic characterization tools are integrated with geological and engineering studies. Targeted drilling from predictions using 3D seismic for porosity development were successful in developing significant reserves at close distances to old wells. Short-lateral and horizontal drilling technologies were tested for improved completion efficiency. Lateral completions should improve economics for both primary and secondary recovery where low permeability is a problem and higher density drilling is limited by drilling cost. Low water injectivity and widely spaced wells have restricted the application of waterflooding in the past. Water injection tests were performed in both a vertical and a horizontal well. Data from these tests were used to predict long-term injection and oil recovery.

  19. Water-use data for the Red River of the North Basin, North Dakota, Minnesota, and South Dakota, 1979-2001

    USGS Publications Warehouse

    Macek-Rowland, Kathleen M.; Arntson, Allan D.; Ryberg, Karen R.; Dahl, Ann L.; Lieb, Amy

    2004-01-01

    The Red River of the North, located in the north-central plains of the United States, plays an important role in population growth and economic development of the region. Because of recent and projected growth in population, industry, and agriculture in the Red River of the North Basin, alternatives to additional water resources will be needed to supplement future water needs. Past and current water-use data are needed to help select the most viable water-resource alternatives. Withdrawal and return flow data were collected from various sources throughout the Red River of the North Basin from 1979 through 2001. The withdrawal data were aggregated by subbasin, monthly totals, and water-use categories. The return flow data were aggregated by subbasin and monthly totals. The Red River of the North Basin was divided into subbasins based on locations of U.S. Geological Survey streamflow-gaging stations and by specifically-identified reaches. Results of the water-use compilation are provided in this report.

  20. Water quality, sediment, and soil characteristics near Fargo-Moorhead urban areas as affected by major flooding of the Red River of the North

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objectives of this study were to assess if urban environments affect floodwater quality, and to determine the quantity and quality of overbank sediment deposited in an urban environment after floodwaters recede. Water samples during major flooding of the Red River of the North (RR) were taken on...

  1. Adsorption and desorption of arsenic to aquifer sediment on the Red River floodplain at Nam Du, Vietnam

    NASA Astrophysics Data System (ADS)

    Thi Hoa Mai, Nguyen; Postma, Dieke; Thi Kim Trang, Pham; Jessen, Søren; Hung Viet, Pham; Larsen, Flemming

    2014-10-01

    The adsorption of arsenic onto aquifer sediment from the Red River floodplain, Vietnam, was determined in a series of batch experiments. Due to water supply pumping, river water infiltrates into the aquifer at the field site and has leached the uppermost aquifer sediments. The leached sediments remain anoxic but contain little reactive arsenic and iron, and are used in our experiments. The adsorption and desorption experiments were carried out by addition or removal of arsenic from the aqueous phase in sediment suspensions under strictly anoxic conditions. Also the effects of HCO3, Fe(II), PO4 and Si on arsenic adsorption were explored. The results show much stronger adsorption of As(V) as compared to As(III), full reversibility for As(III) adsorption and less so for As(V). The presence or absence of HCO3 did not influence arsenic adsorption. Fe(II) enhanced As(V) sorption but did not influence the adsorption of As(III) in any way. During simultaneous adsorption of As(III) and Fe(II), As(III) was found to be fully desorbable while Fe(II) was completely irreversibly adsorbed and clearly the two sorption processes are uncoupled. Phosphate was the only solute that significantly could displace As(III) from the sediment surface. Compiling literature data on arsenic adsorption to aquifer sediment in Vietnam and Bangladesh revealed As(III) isotherms to be almost identical regardless of the nature of the sediment or the site of sampling. In contrast, there was a large variation in As(V) adsorption isotherms between studies. A tentative conclusion is that As(III) and As(V) are not adsorbing onto the same sediment surface sites. The adsorption behavior of arsenic onto aquifer sediments and synthetic Fe-oxides is compared. Particularly, the much stronger adsorption of As(V) than of As(III) onto Red River as well as on most Bangladesh aquifer sediments, indicates that the perception that arsenic, phosphate and other species compete for the same surface sites of iron oxides in sediments with properties similar to those of, for example a synthetic goethite, probably is not correct. A simple two-component Langmuir adsorption model was constructed to quantitatively describe the reactive transport of As(III) and PO4 in the aquifer.

  2. Late Pleistocene to Holocene river terrace deformation within the Little Salmon Fault Zone: insights to tectonic transition from Cascadia Subduction to San Andreas transform stress regimes, Van Duzen river, Northern California

    NASA Astrophysics Data System (ADS)

    Nicovich, S.; Hemphill-Haley, M. A.; Leroy, T. H.

    2014-12-01

    The southern Cascadia subduction zone (CSZ) of northwestern California exhibits northeast-directed contraction, transitioning to north-northwest directed translation within the broad San Andreas fault (SAF) transform margin to the south. The Little Salmon fault (LSF) is one of the southern-most, active thrust faults within the onshore fold and thrust belt of the CSZ, and lies proximal to the transition from compressional to dextral stress across the Mendocino Triple Junction. Thus, it is an ideal location to characterize strain associated with this complex region of transitional stress regimes. High precision topographic data (LiDAR) enabled detailed mapping of geomorphic features that would otherwise be obscured by dense vegetation of the area. A northwest trending lineament, sub-parallel and south of the main splay of the LSF is observed on LiDAR imagery. The lineament exhibits potential up-to-the-northeast offset and traverses several Van Duzen river terrace risers and treads that range from Pleistocene to potentially Holocene in age. A shallow, exploratory trench was hand-excavated across the lineament. The shallow, roughly 1.5 m-deep, 16 m-long trench exposed imbricated gravels that dip into the base of the trench in the upper end. Coring within the lower end of the trench mapped the southern extent of the gravels. The architecture of the unconsolidated, clast-supported gravel deposit displays a diffuse up-to-the-northeast step. More obvious offset may be expressed at lower depths and/or in mediums with more confining stress. The linear map expression of the lineament across relatively steep terrain suggests that the fault may be relatively steeply dipping. Conjugate deformation shear bands within Neogene bedrock nearby along the Van Duzen river provide additional information about the state of stress within this area of transition.

  3. Historic and unregulated monthly streamflow for selected sites in the Red River of the North basin in North Dakota, Minnesota, and South Dakota, 1931-99

    USGS Publications Warehouse

    Emerson, Douglas G.; Dressler, Valerie M.

    2002-01-01

    Operation of the Garrison Diversion Unit in North Dakota may have various effects on the quantity and quality of streamflow in the Sheyenne River and the Red River of the North. To model the effects that the Garrison Diversion Unit could have on water quality, gaged and estimated historic streamflow data and estimated unregulated streamflow data were compiled to develop a complete monthly streamflow record for January 1931 through September 1999 (the data-development period) for 35 sites in the Red River of the North Basin in North Dakota, Minnesota, and South Dakota.During the entire data-development period, gaged streamflow data were available for only 4 of the 35 sites, incomplete data of various length were available for 10 sites, and no data were available for 21 sites. Drainage- area ratio and Maintenance of Variance Extension Type 1 methods were used to estimate the historic streamflow for months when no data were available.Unregulated streamflow for the 35 sites was estimated by eliminating the hydrologic effects of Orwell Reservoir, Lake Traverse, Mud Lake, Lake Ashtabula, and surface-water withdrawals. Modeled flows at the Red River of the North at Wahpeton by the U.S. Army Corps of Engineers were used to eliminate the effects of Orwell Reservoir, Lake Traverse, and Mud Lake, and water-balance procedures were used to eliminate the effects of Lake Ashtabula.

  4. An experimental study of the impact of location on the effectiveness of recruitment clusters for red-cockaded woodpeckers at the Savannah River Site.

    SciTech Connect

    Walters, J., R.; Taylor, T., B.; Daniels, S., J.

    2003-05-29

    This report summarizes results of research on red-cockaded woodpeckers (Picoides borealis) conducted by personnel from Virginia Polytechnic Institute and State University (Virginia Tech) and the Duke Marine Laboratory at the Savannah River Site (SRS), South Carolina, from September 29, 2000 through September 28, 2002. This period represents the first two years of a five-year Cooperative Agreement between Virginia Tech and the USDA Forest Service, Savannah River. This report serves as an Interim Project Report with respect to the Cooperative Agreement (No. OO-CA-ll 083600-010), and a Final Project Report for the initial award to Virginia Tech (FRS No.428911).

  5. Ground-water data for the Salt Basin, Eagle Flat, Red Light Draw, Green River Valley, and Presidio Bolson in westernmost Texas

    USGS Publications Warehouse

    White, Donald Edward; Gates, J.S.; Smith, Joe T.; Fry, B.J.

    1978-01-01

    From October 1971 through October 1974, the U.S. Geological Survey collected groundwater data in the basins in Texas west of the Pecos River drainage area and northwest of the Big Bend country. The basins included are, from east to west: The Presidio Bolson; the Salt Basin; Green River Valley, Eagle Flat, and Red Light Draw. The data collection program consisted of an inventory of all major irrigation, municipal-supply, and industrial wells; selected stock and domestic wells; and selected springs. Water samples were collected from representative wells and springs for chemical analyses. (Woodard-USGS)

  6. Ground-water data for the Salt Basin, Eagle Flat, Red Light Draw, Green River Valley and Presidio Bolson in westernmost Texas

    USGS Publications Warehouse

    White, Donald E.; Gates, Joseph S.; Smith, James T.; Fry, Bonnie J.

    1980-01-01

    From October 1971 through October 1974. the U.S. Geological Survey collected ground-water data in the basins in Texas west of the Pecos River drainage area and northwest of the Big Bend country. The basins included are, from east to west: The Presidio Bolson; the Salt Basin; Green River Valley, Eagle Flat, and Red Light Draw. These data, which were collected in cooperation with the Texas Department of Water Resources (formerly Texas Water Development Board), will provide information for a continuing assessment of water availability within the State.

  7. Timing and rate of exhumation along the Litang fault system, implication for fault reorganization in Southeast Tibet

    NASA Astrophysics Data System (ADS)

    Zhang, Yuan-Ze; Replumaz, Anne; Wang, Guo-Can; Leloup, Philippe Hervé; Gautheron, Cécile; Bernet, Matthias; Beek, Peter; Paquette, Jean Louis; Wang, An; Zhang, Ke-Xin; Chevalier, Marie-Luce; Li, Hai-Bing

    2015-06-01

    The Litang fault system that crosses the Litang Plateau, a low relief surface at high elevation (~4200-4800 m above sea level) that is not affected by regional incision, provides the opportunity to study exhumation related to tectonics in the SE Tibetan Plateau independently of regional erosion. Combining apatite and zircon fission track with apatite (U-Th)/He thermochronologic data, we constrain the cooling history of the Litang fault system footwall along two transects. Apatite fission track ages range from 4 to 16 Ma, AHe ages from 2 to 6 Ma, and one zircon fission track age is ~99 Ma. These data imply a tectonic quiet period sustained since at least 100 Ma with a slow denudation rate of ~0.03 km/Ma, interrupted at 7 to 5 Ma by exhumation at a rate between 0.59 and 0.99 km/Ma. We relate that faster exhumation to the onset of motion along the left-lateral/normal Litang fault system. That onset is linked to a Lower Miocene important kinematic reorganization between the Xianshuihe and the Red River faults, with the eastward propagation of the Xianshuihe fault along the Xiaojiang fault system and the formation of the Zhongdian fault. Such strike-slip faults allow the sliding to the east of a wide continental block, with the Litang fault system accommodating differential motion between rigid blocks. The regional evolution appears to be guided by the strike-slip faults, with different phases of deformation, which appears more in agreement with an "hidden plate-tectonic" model rather than with a "lower channel flow" model.

  8. Hydrogeology and physical characteristics of water samples at the Red River aluminum site, Stamps, Arkansas, April 2001

    USGS Publications Warehouse

    Czarnecki, John B.; Stanton, Gregory P.; Freiwald, David A.

    2001-01-01

    The Red River Aluminum site near Stamps, Arkansas, contains waste piles of salt cake and metal byproducts from the smelting of aluminum. The waste piles are subjected to about 50 inches of rainfall a year, resulting in the dissolution of the salts and metal. To assess the potential threat to underlying ground-water resources at the site, its hydrogeology was characterized by measuring water levels and field parameters of water quality in 23 wells and at 2 surface-water sites. Seventeen of these monitor wells were constructed at various depths for this study to allow for the separate characterization of the shallow and deep ground-water systems, the calculation of vertical gradients, and the collection of water samples at different depths within the flow system. Lithologic descriptions from drill-hole cuttings and geophysical logs indicate the presence of interbedded sands, gravels, silts, and clays to depths of 65 feet. The regionally important Sparta aquifer underlies the site. Water levels in shallow wells indicate radial flow away from the salt-cake pile located near the center of the site. Flow in the deep system is to the west and southwest toward Bodcau Creek. Water-level data from eight piezometer nests indicate a downward hydraulic gradient from the shallow to deep systems across the site. Values of specific conductance (an indicator of dissolved salts) ranged from 215 to 196,200 microsiemens per centimeter and indicate that saline waters are being transported horizontally and vertically downward away from the site

  9. Establishment of a viable population of red-cockaded woodpeckers at the Savannah River Plant: Progress report, 1985 through 1988

    SciTech Connect

    Allen, D.H.; Lennartz, M.R.

    1988-12-06

    In 1985 the Southeastern Forest Experiment Station (SEFES) in cooperation with the Department of Energy began research on the red-cockaded woodpecker (RCW) at the Savannah River Plant (SRP). In early 1986 there were four RCW's on the SRP, including one pair in colony 19 and solitary males in colonies 5 and 16. Because of the decline in past years, it was deemed necessary to bring in birds from outside the plant to augment the local RCW population. In the next two years, translocations and local reproduction increased the population to 14 birds and the number of breeding clans from one to three. Although only two clans bred and fledged young in 1988, the population remains at 14 birds and has expanded to occupy five colony sites. Research and management activities implemented or continued over the past year include: translocations of birds within the SRP and from the Francis Marion National Forest (FMNF) to SRP, herbicide, burning and thinning for hardwood control and increased diameter growth of pines, the removal of flying squirrels from active colonies, and the installation of nest boxes, RCW artificial cavities and metal restrictors to reduce competition from other species.

  10. Comparison of mercury concentrations in liver, muscle, whole bodies, and composites of fish from the Red River of the North

    USGS Publications Warehouse

    Goldstein, Robert M.; Brigham, Mark E.; Stauffer, Joseph C.

    1996-01-01

    Carp (Cyprinus carpio) from four sites and channel catfish (Ictalurus punctatus) from one site in the Red River of the North in 1994 were analyzed for total mercury content. In carp, mercury concentrations differed among liver, muscle, and whole bodies (0.11, 0.31, and 0.18 µg/g wet weight, respectively), between large and small size groups, but not location. Mercury distribution in channel catfish tissues differed from that in carp. Liver and muscle tissue had similar mean concentrations; each was higher than whole-body concentrations (0.16, 0.18, and 0.11 µg/g, respectively). Mercury concentrations were not significantly different between the two size groups of channel catfish. Weighted-mean mercury concentrations from seven individual fish agreed closely (usually within 10%) with concentrations determined on physical composites of the same fish. The ratio of mercury in whole bodies to mercury in muscle was similar for both carp and channel catfish. Historical data indicate that this ratio may be applicable to other species and locations. The ratio of mercury in livers to whole bodies and muscle differed between carp and channel catfish, which may reflect physiological differences between different trophic groups.

  11. Data for selected gaging stations in the upper Red River of the North Basin in Minnesota, September 2001 through September 2003

    USGS Publications Warehouse

    Damschen, William C.; Nustad, Rochelle A.

    2005-01-01

    Surface-water and water-quality data were collected to use in development of upper Red River of the North Basin Total Maximum Daily Loads (TMDLs). This report presents the data that were collected. During September 2001 through September 2003, data were collected at 13 selected gaging stations in the upper Red River of the North Basin. Continuous streamflow data were collected at three of the gaging stations. Water-quality samples were collected at all 13 gaging stations; and, simultaneous with sample collection, in-stream specific conductance, pH, water temperature, dissolved oxygen, and turbidity were measured. Samples were analyzed for selected nutrients, selected bacteria, chlorophyll a, and suspended sediment. Continuous in-stream water-quality monitors were installed at two gaging stations to measure specific conductance, pH, water temperature, dissolved oxygen, and turbidity.

  12. Mercury, methylmercury, and other water-quality data from flood-control impoundments and natural waters of the Red River of the North Basin, Minnesota, 1997-99

    USGS Publications Warehouse

    Brigham, Mark E.; Olson, Mark L.; DeWild, John F.

    1999-01-01

    It is now well documented that impoundment of natural waters, with inundation of terrestrial area, results in enhanced conversion of inorganic mercury to methylmercury, a form that is toxic and bioaccumulates to a greater extent than inorganic mercury. Concentrations of mercury, methylmercury, and other water-quality constituents are reported from water sampled from flood-control impoundments and natural (unimpounded) waters of the Red River of the North Basin from 1997-99.

  13. Wide-area estimates of evapotranspiration by red gum (Eucalyptus camaldulensis) and associated vegetation in the Murray-Darling River Basin, Australia

    USGS Publications Warehouse

    Nagler, Pamela L.; Doody, Tanya M.; Glenn, Edward P.; Jarchow, Christopher J; Barreto-Munoz, Armando; Didan, Kamel

    2016-01-01

    Floodplain red gum forests (Eucalyptus camaldulensis plus associated grasses, reeds and sedges) are sites of high biodiversity in otherwise arid regions of southeastern Australia. They depend on periodic floods from rivers, but dams and diversions have reduced flood frequencies and volumes, leading to deterioration of trees and associated biota. There is a need to determine their water requirements so environmental flows can be administered to maintain or restore the forests. Their water requirements include the frequency and extent of overbank flooding, which recharges the floodplain soils with water, as well as the actual amount of water consumed in evapotranspiration (ET). We estimated the flooding requirements and ET for a 38 134 ha area of red gum forest fed by the Murrumbidgee River in Yanga National Park, New South Wales. ET was estimated by three methods: sap flux sensors placed in individual trees; a remote sensing method based on the Enhanced Vegetation Index from MODIS satellite imagery and a water balance method based on differences between river flows into and out of the forest. The methods gave comparable estimates yet covered different spatial and temporal scales. We estimated flood frequency and volume requirements by comparing Normalized Difference Vegetation Index values from Landsat images with flood history from 1995 to 2014, which included both wet periods and dry periods. ET during wet years is about 50% of potential ET but is much less in dry years because of the trees' ability to control stomatal conductance. Based on our analyses plus other studies, red gum trees at this location require environmental flows of 2000 GL yr−1 every other year, with peak flows of 20 000 ML d−1, to produce flooding sufficient to keep them in good condition. However, only about 120–200 GL yr−1 of river water is consumed in ET, with the remainder flowing out of the forest where it enters the Murray River system.

  14. Chlorinated hydrocarbons and mercury in sediments, red-winged blackbirds (Agelaius phoeniceus) and tree swallows (Tachycineta bicolor) from wetlands in the Great Lakes-St. Lawrence River basin

    SciTech Connect

    Bishop, C.A.; Koster, M.D.; Chek, A.A.; Hussell, D.J.T.; Jock, K.

    1995-03-01

    In 1991, the authors collected red-winged blackbird (Agelauis phoeniceus) eggs and tree swallow (Tachycineta bicolor) eggs and nestlings, and sediment samples from 2 wetland sites in the Great lakes and St. Lawrence River basin. They analyzed for chlorinated hydrocarbons and total mercury and found that biota contained contaminant concentrations which were one to two orders of magnitude above those in sediments. Maximum concentrations of contaminants were found in Akwesasne, St. Lawrence river (PCBs = 18,558.8 ng/g in red-winged blackbird eggs, oxychlordane = 58.8/g and mirex = 40.1 ng/g in tree swallow eggs); Mud Creek, Lake Erie and Cootes Paradise. Despite the migratory habits of red-winged blackbirds and tree swallows, agreement among biota and sediment in geographic variation of contaminant concentrations supports the use of these animals as biomonitors of persistent chemicals. Although chlorinated hydrocarbon concentrations in red-winged blackbird eggs were significantly correlated with sediment contamination, the local nature of the tree swallow chick diet suggests that nestlings would be the best indicator of local contaminant trends.

  15. Mortality associated with melarsomine dihydrochloride administration in two North American river otters (Lontra canadensis) and a red panda (Ailurus fulgens fulgens).

    PubMed

    Neiffer, Donald L; Klein, Edwin C; Calle, Paul P; Linn, Michael; Terrell, Scott P; Walker, Rodney L; Todd, Donna; Vice, Carol C; Marks, Steven K

    2002-09-01

    Two adult North American river otters (Lontra canadensis) and an adult red panda (Ailurus fulgens fulgens) at three separate institutions died within 22 hr after receiving single 2.5- to 2.7-mg/kg doses of melarsomine dihydrochloride administered in the epaxial musculature as a treatment for filarid nematodes. One otter had a suspected Dirofilaria immitis infection, the other had a confirmed D. lutrae infection, and the red panda had a confirmed Dirofilaria sp. infection, presumably with D. immitis. Postmortem examinations revealed similar gross lesions, although they were less severe in the red panda. The trachea and primary bronchi contained abundant foamy fluid, the lungs were mottled with areas of consolidation, and the pulmonary parenchyma exuded abundant fluid at the cut section. Histologic evaluation revealed acute pulmonary edema, which resulted in respiratory failure and death. There may have been direct pulmonary cellular toxicity of melarsomine dihydrochloride or a severe systemic anaphylactic reaction to antigens released after parasite death. An idiosyncratic drug reaction or a low therapeutic index of melarsomine probably caused the death of the three individuals. Melarsomine dihydrochloride use should be avoided in North American river otters and red pandas. PMID:12462491

  16. Red waters of Myrionecta rubra are biogeochemical hotspots for the Columbia River estuary with impacts on primary/secondary productions and nutrient cycles

    SciTech Connect

    Herfort, Lydie; Peterson, Tawnya D.; Prahl, Fredrick G.; McCue, Lee Ann; Needoba, Joe A.; Crump, Byron C.; Roegner, G. Curtis; Campbell, Victoria; Zuber, Peter A.

    2012-02-29

    The localized impact of blooms of the mixotrophic ciliate Myrionecta rubra in the Columbia River estuary during 2007-2010 was evaluated with biogeochemical, light microscopy, physiological and molecular data. M. rubra affected surrounding estuarine nutrient cycles, as indicated by high and low concentrations of organic nutrients and inorganic nitrogen, respectively, associated with red waters. M. rubra blooms also altered the energy transfer pattern in patches of the estuarine water that contain the ciliate by creating areas characterized by high primary production and elevated levels of fresh autochthonous particulate organic matter, therefore shifting the trophic status in emergent red water areas of the estuary from net heterotrophy towards autotrophy. The pelagic estuarine bacterial community structure was unaffected by M. rubra abundance, but red waters of the ciliate do offer a possible link between autotrophic and heterotrophic processes since they were associated with elevated dissolved organic matter and enhanced microbial secondary production. Taken together these findings suggest that M. rubra red waters are biogeochemical hotspots of the Columbia River estuary.

  17. Segmentation and the coseismic behavior of Basin and Range normal faults: examples from east-central Idaho and southwestern Montana, U.S.A.

    USGS Publications Warehouse

    Crone, A.J.; Haller, K.M.

    1991-01-01

    The range-front normal faults of the Lost River and Lemhi Ranges, and the Beaverhead and Tendoy Mountains in east-central Idaho and southwestern Montana have well-preserved fault scarps on Quaternary deposits along much of their lengths. Fault-scarp morphology, the age of deposits displaced by the faults, and the morphology of the range fronts provide a basis for dividing the faults into segments that are typically 20-25 km long. The Lost River, Lemhi and Beaverhead fault zones are 141-151 km long, and each has six segments. The 60-km-long Red Rock fault (the range-front fault of the Tendoy Mountains) has two central segments that have been active in late Quaternary time; these two segments span the central 27 km of the fault. We recognize four characteristics that help to identify segment boundaries: (1) major en e??chelon offsets or pronounced gaps in the continuity of fault scarps; (2) distinct, persistent, along-strike changes in fault-scarp morphology that indicate different ages of faulting; (3) major salients in the range front; and (4) transverse bedrock ridges where the cumulative throw is low compared to other places along the fault zone. Only features whose size is measured on the scale of kilometers are regarded as significant enough to represent a segment boundary that could inhibit or halt a propagating rupture. The ability to identify segments of faults that are likely to behave as independent structural entities will improve seismic-hazard assessment. However, one should not assume that the barriers at segment boundaries will completely stop all propagating ruptures. The topographic expression of mountain ranges is evidence that, at times during their history, all barriers fail. Some barriers apparently create 'leaky' segment boundaries that impede propagating ruptures but do not completely prevent faulting on adjacent segments. ?? 1991.

  18. Simultaneous and continuous measurements of dissolved CO2, CH4, N2O and CO in rivers using Fourier-Transform-InfraRed (FTIR) spectrometry

    NASA Astrophysics Data System (ADS)

    Warneke, Thorsten; Müller, Denise; Caldow, Christopher; Rixen, Tim; Notholt, Justus

    2015-04-01

    We have coupled a Fourier-Transform InfraRed (FTIR) trace gas analyser to an equilibrator, which allows the simultaneous and continuous measurement of dissolved CO2, CH4, N2O and CO in water. The FTIR-technique has a high precision over a wide range of concentrations, making it very suitable for the measurement of these gases in freshwater systems. We have employed this measurement system on a commercial river barge on the Elbe river (Czech Republic, Germany) and on a fisher boat in the coastal area of Sarawak (Malaysia). In addition we have performed stationary continuous measurements at a small river in Northern Germany over the duration of 3 months. The presentation will outline the advantages and disadvantages of the FTIR-technique for freshwater measurements and will present results from the measurement campaigns.

  19. Genesis of economic relevant fresh groundwater resources in Pleistocene/ Neogene aquifers in Nam Dinh (Red River Delta, Vietnam).

    NASA Astrophysics Data System (ADS)

    Wagner, F.; Ludwig, R. R.; Noell, U.; Hoang, H. V.; Pham, N. Q.; Larsen, F.; Lindenmaier, F.

    2012-04-01

    In the Southern Red River Delta (Nam Dinh Province, Vietnam), a local lens of low saline pore water of high quality has been identified in unconsolidated Pleistocene and Neogene aquifers, which are regionally known to contain brackish and saline pore waters. Since the 1990ies, ongoing overexploitation of the fresh groundwater results in decreasing GW heads up to 0.6 m/a and the development of a regional abstraction cone. The presented study focuses on distribution and genesis of fresh and saline pore waters and reflects the results in frame of the regional hydrogeological context. Observations of the geological structure and groundwater dynamics combined with hydrochemical and isotopic studies suggest adjacent Triassic hard rock aquifers as the major source for fresh Pleistocene and Neogene groundwater. Salinization status in the economically most relevant Pleistocene aquifer has been studied based on archive and new hydrochemical and geophysical data. Own hydrochemical field studies as well as laboratory measurements of the specific resistivity of dry sediment samples allow the translation of induction logging data from existing monitoring wells into vertical pore water salinity profiles. This approach suggests the regional occurrence of saline pore water in shallow Holocene sediments in the working area, as confirmed by pore water studies in Hoan et al. (2010). Interpretation of induction logging and stable isotope data suggest vertical diffusion of saline pore water in shallow Holocene sediments as a source for high saline pore water in deeper aquifers. Analytical diffusion modeling for a period of 3000 years confirms that vertical diffusion of Holocene paleo-sea water can explain saline pore water in Pleistocene and Neogene aquifers in a stagnant environment. The constant influx of fresh groundwater from adjacent Triassic hard rocks results in flushing of the primary Pleistocene and Neogene pore water and inhibits the infiltration of saline water from marine Holocene sediments. Consequently, 14C groundwater age dating suggests increasing groundwater ages from fresh to saline pore water in Pleistocene and Neogene up to 14 ka, presuming that contamination with dead carbon is neglectable. Highest 14C ages of low saline water has been observed in the center of the exploited fresh water lens reaching up to 10 ka, reflecting low groundwater flux and recharge rates. Due to the overexploitation, the natural coastward directed groundwater flow has turned towards the centre of the abstraction cone with horizontal apparent velocities of up to 0.6 m/a. This suggests, that brackish and higher saline groundwater from the Red River area (East Nam Dinh) and offshore migrates towards the fresh water lens. Thus, more sustainable exploitation strategies urgently must be implemented to reduce overexploitation of limited and valuable fresh groundwater resources in Nam Dinh Province. Reference: Hoan H., Pham Q. N., Larsen F. Tran L. V., Wagner F., Christiansen A.V. (2010): Processes Controlling High Saline Groundwater in the Nam Dinh Province, Vietnam. 2nd Asia-Pacific Coastal Aquifer Management Meeting (ACAMM), October 18-21, 2011, Jeju Island, Korea.

  20. Genetic polymorphisms in glutathione S-transferase (GST) superfamily and arsenic metabolism in residents of the Red River Delta, Vietnam

    SciTech Connect

    Agusa, Tetsuro; Iwata, Hisato; Fujihara, Junko; Kunito, Takashi; Takeshita, Haruo; Tu Binh Minh; Pham Thi Kim Trang; Pham Hung Viet; Tanabe, Shinsuke

    2010-02-01

    To elucidate the role of genetic factors in arsenic metabolism, we investigated associations of genetic polymorphisms in the members of glutathione S-transferase (GST) superfamily with the arsenic concentrations in hair and urine, and urinary arsenic profile in residents in the Red River Delta, Vietnam. Genotyping was conducted for GST omega1 (GSTO1) Ala140Asp, Glu155del, Glu208Lys, Thr217Asn, and Ala236Val, GST omega2 (GSTO2) Asn142Asp, GST pi1 (GSTP1) Ile105Val, GST mu1 (GSTM1) wild/null, and GST theta1 (GSTT1) wild/null. There were no mutation alleles for GSTO1 Glu208Lys, Thr217Asn, and Ala236Val in this population. GSTO1 Glu155del hetero type showed higher urinary concentration of As{sup V} than the wild homo type. Higher percentage of DMA{sup V} in urine of GSTM1 wild type was observed compared with that of the null type. Strong correlations between GSTP1 Ile105Val and arsenic exposure level and profile were observed in this study. Especially, heterozygote of GSTP1 Ile105Val had a higher metabolic capacity from inorganic arsenic to monomethyl arsenic, while the opposite trend was observed for ability of metabolism from As{sup V} to As{sup III}. Furthermore, other factors including sex, age, body mass index, arsenic level in drinking water, and genotypes of As (+ 3 oxidation state) methyltransferase (AS3MT) were also significantly co-associated with arsenic level and profile in the Vietnamese. To our knowledge, this is the first study indicating the associations of genetic factors of GST superfamily with arsenic metabolism in a Vietnamese population.

  1. Genetic polymorphisms in AS3MT and arsenic metabolism in residents of the Red River Delta, Vietnam

    SciTech Connect

    Agusa, Tetsuro; Iwata, Hisato Fujihara, Junko; Kunito, Takashi; Takeshita, Haruo; Minh, Tu Binh; Trang, Pham Thi Kim; Viet, Pham Hung; Tanabe, Shinsuke

    2009-04-15

    To elucidate the role of genetic factors in arsenic (As) metabolism, we studied associations of single nucleotide polymorphisms (SNPs) in As (+ 3 oxidation state) methyltransferase (AS3MT) with the As concentrations in hair and urine, and urinary As profile in residents in the Red River Delta, Vietnam. Concentrations of total As in groundwater were 0.7-502 {mu}g/l. Total As levels in groundwater drastically decreased by using sand filter, indicating that the filter could be effective to remove As from raw groundwater. Concentrations of inorganic As (IAs) in urine and total As in hair of males were higher than those of females. A significant positive correlation between monomethylarsonic acid (MMA)/IAs and age in females indicates that older females have higher methylation capacity from IAs to MMA. Body mass index negatively correlated with urinary As concentrations in males. Homozygote for SNPs 4602AA, 35991GG, and 37853GG, which showed strong linkage disequilibrium (LD), had higher percentage (%) of dimethylarsinic acid (DMA) in urine. SNPs 4740 and 12590 had strong LD and associated with urinary %DMA. Although SNPs 6144, 12390, 14215, and 35587 comprised LD cluster, homozygotes in SNPs 12390GG and 35587CC had lower DMA/MMA in urine, suggesting low methylation capacity from MMA to DMA in homo types for these SNPs. SNPs 5913 and 8973 correlated with %MMA and %DMA, respectively. Heterozygote for SNP 14458TC had higher MMA/IAs in urine than TT homozygote, indicating that the heterozygote may have stronger methylation ability of IAs. To our knowledge, this is the first study on the association of genetic factors with As metabolism in Vietnamese.

  2. Regional-scale assessment of soil salinity in the Red River Valley using multi-year MODIS EVI and NDVI.

    PubMed

    Lobell, D B; Lesch, S M; Corwin, D L; Ulmer, M G; Anderson, K A; Potts, D J; Doolittle, J A; Matos, M R; Baltes, M J

    2010-01-01

    The ability to inventory and map soil salinity at regional scales remains a significant challenge to scientists concerned with the salinization of agricultural soils throughout the world. Previous attempts to use satellite or aerial imagery to assess soil salinity have found limited success in part because of the inability of methods to isolate the effects of soil salinity on vegetative growth from other factors. This study evaluated the use of Moderate Resolution Imaging Spectroradiometer (MODIS) imagery in conjunction with directed soil sampling to assess and map soil salinity at a regional scale (i.e., 10-10(5) km(2)) in a parsimonious manner. Correlations with three soil salinity ground truth datasets differing in scale were made in Kittson County within the Red River Valley (RRV) of North Dakota and Minnesota, an area where soil salinity assessment is a top priority for the Natural Resource Conservation Service (NRCS). Multi-year MODIS imagery was used to mitigate the influence of temporally dynamic factors such as weather, pests, disease, and management influences. The average of the MODIS enhanced vegetation index (EVI) for a 7-yr period exhibited a strong relationship with soil salinity in all three datasets, and outperformed the normalized difference vegetation index (NDVI). One-third to one-half of the spatial variability in soil salinity could be captured by measuring average MODIS EVI and whether the land qualified for the Conservation Reserve Program (a USDA program that sets aside marginally productive land based on conservation principles). The approach has the practical simplicity to allow broad application in areas where limited resources are available for salinity assessment. PMID:20048292

  3. Faulted Barn

    This barn is faulted through the middle; the moletrack is seen in the foreground with the viewer standing on the fault. From the air one can see metal roof panels of the barn that rotated as the barn was faulted....

  4. Salton Sea Satellite Image Showing Fault Slip

    Landsat satellite image (LE70390372003084EDC00) showing location of surface slip triggered along faults in the greater Salton Trough area. Red bars show the generalized location of 2010 surface slip along faults in the central Salton Trough and many additional faults in the southwestern section of t...

  5. The timing of strike-slip shear along the Ranong and Khlong Marui faults, Thailand

    NASA Astrophysics Data System (ADS)

    Watkinson, Ian; Elders, Chris; Batt, Geoff; Jourdan, Fred; Hall, Robert; McNaughton, Neal J.

    2011-09-01

    The timing of shear along many important strike-slip faults in Southeast Asia, such as the Ailao Shan-Red River, Mae Ping and Three Pagodas faults, is poorly understood. We present 40Ar/39Ar, U-Pb SHRIMP and microstructural data from the Ranong and Khlong Marui faults of Thailand to show that they experienced a major period of ductile dextral shear during the middle Eocene (48-40 Ma, centered on 44 Ma) which followed two phases of dextral shear along the Ranong Fault, before the Late Cretaceous (>81 Ma) and between the late Paleocene and early Eocene (59-49 Ma). Many of the sheared rocks were part of a pre-kinematic crystalline basement complex, which partially melted and was intruded by Late Cretaceous (81-71 Ma) and early Eocene (48 Ma) tin-bearing granites. Middle Eocene dextral shear at temperatures of ˜300-500°C formed extensive mylonite belts through these rocks and was synchronous with granitoid vein emplacement. Dextral shear along the Ranong and Khlong Marui faults occurred at the same time as sinistral shear along the Mae Ping and Three Pagodas faults of northern Thailand, a result of India-Burma coupling in advance of India-Asia collision. In the late Eocene (<37 Ma) the Ranong and Khlong Marui faults were reactivated as curved sinistral branches of the Mae Ping and Three Pagodas faults, which were accommodating lateral extrusion during India-Asia collision and Himalayan orogenesis.

  6. Data mining of external and internal forcing of fluvial systems for catchment management: A case study on the Red River (Song Hong), Vietnam

    NASA Astrophysics Data System (ADS)

    Schmitt, Rafael; Bizzi, Simone; Castelletti, Andrea

    2013-04-01

    The understanding of river hydromorphological processes has been recognized in the last decades as a priority of modern catchment management, since interactions of natural and anthropogenic forces within the catchment drives fluvial geomorphic processes, which shape physical habitat, affect river infrastructures and influence freshwater ecological processes. The characterization of river hydromorphological features is commonly location and time specific and highly resource demanding. Therefore, its routine application at regional or national scales and the assessment of spatio-temporal changes as reaction to internal and external disturbances is rarely feasible at present. Information ranging from recently available high-resolution remote-sensing data (such as DEM), historic data such as land use maps or aerial photographs and monitoring networks of flow and rainfall, open up novel and promising capacity for basin-wide understanding of dominant hydromorphological drivers. Analysing the resulting multiparametric data sets in their temporal and spatial dimensions requires sophisticated data mining tools to exploit the potential of this information. We propose a novel framework that allows for the quantitative assessment of multiparametric data sets to identify classes of channel reaches characterized by similar geomorphic drivers using remote-sensing data and monitoring networks available in the catchment. This generic framework was applied to the Red River (Song Hong) basin, the second largest basin (87,800 sq.km) in Vietnam. Besides its economic importance, the river is experiencing severe river bed incisions due to recent construction of new dams in the upstream part of the catchment and sand mining in the surrounding of the capital city Hanoi. In this context, characterized by an high development rate, current efforts to increase water productivity and minimize impacts on the fluvial systems by means of focused infrastructure and management measures require a thorough understanding of the fluvial system and, in particular, basin-wide assessment of resilience to human-induced change. . The framework proposed has allowed producing high-dimensional samples of spatially distributed geomorphic drivers at catchment scale while integrating recent and historic point records for the Red River basin. This novel dataset has been then analysed using self-organizing maps (SOM) an artificial neural network model in combination with fuzzy clustering. The above framework is able to identify non-trivial correlations in driving forces and to derive a fuzzy classification at reach scale which represents continuities and discontinuities in the river systems. The use of the above framework allowed analyzing the spatial distribution of geomorphic features at catchment scale, revealing patterns of similarities and dissimilarities within the catchment and allowing a classification of river reaches characterized by similar geomorphic drivers, fluvial processes and response to external forcing. The paper proposes an innovative and promising technique to produce hydromorphological classifications at catchment scale integrating historical and recent available high resolution data. The framework aims at opening the way to a more structured organization and analyses of recently available information on river geomorphic features, so far often missing or rarely exploited. This approach poses the basis to produce efficient databases of river geomorphic features and processes related to natural and anthropogenic drivers. That is a necessity in order to enhance our understanding of the internal and external forces which drive fluvial systems, to assess the resilience and dynamic of river landscapes and to develop the more efficient river management strategies of the future.

  7. Water-quality trend analysis and sampling design for streams in the Red River of the North Basin, Minnesota, North Dakota, and South Dakota, 1970-2001

    USGS Publications Warehouse

    Vecchia, Aldo V.

    2005-01-01

    The Bureau of Reclamation is considering several alternatives to meet the future municipal, rural, and industrial water-supply needs in the Red River of the North (Red River) Basin, and an environmental impact statement is being prepared to evaluate the potential effects of the various alternatives on the water quality and aquatic health in the basin in relation to the historical variability of streamflow and constituent concentration. Therefore, a water-quality trend analysis was needed to determine the amount of natural water-quality variability that can be expected to occur in the basin, to determine if significant water-quality changes have occurred as a result of human activities, to explore potential causal mechanisms for water-quality changes, and to establish a baseline from which to monitor future water-quality trends. This report presents the results of a study conducted by the U.S. Geological Survey, in cooperation with the Bureau of Reclamation, to analyze historical water-quality trends in two dissolved major ions, dissolved solids, three nutrients, and two dissolved trace metals for nine streamflow-gaging stations in the basin. Annual variability in streamflow in the Red River Basin was high during the trend-analysis period (1970-2001). The annual variability affects constituent concentrations in individual tributaries to the Red River and, in turn, affects constituent concentrations in the main stem of the Red River because of the relative streamflow contribution from the tributaries to the main stem. Therefore, an annual concentration anomaly, which is an estimate of the interannual variability in concentration that can be attributed to long-term variability in streamflow, was used to analyze annual streamflow-related variability in constituent concentrations. The concentration trend is an estimate of the long-term systematic changes in concentration that are unrelated to seasonal or long-term variability in streamflow. Concentrations that have both the seasonal and annual variability removed are called standardized concentrations. Numerous changes that could not be attributed to natural streamflow-related variability occurred in the standardized concentrations during the trend-analysis period. During various times from the late 1970's to the mid-1990's, significant increases occurred in standardized dissolved sulfate, dissolved chloride, and dissolved- solids concentrations for eight of the nine stations for which water-quality trends were analyzed. Significant increases also occurred from the early 1980's to the mid-1990's for standardized dissolved nitrite plus nitrate concentrations for the main-stem stations. The increasing concentrations for the main-stem stations indicate the upward trends may have been caused by human activities along the main stem of the Red River. Significant trends for standardized total ammonia plus organic nitrogen concentrations occurred for most stations. The fitted trends for standardized total phosphorus concentrations for one tributary station increased from the late 1970's to the early 1980's and decreased from the early 1980's to the mid-1990's. Small but insignificant increases occurred for two main-stem stations. No trends were detected for standardized dissolved iron or dissolved manganese concentrations. However, the combination of extreme high-frequency variability, few data, and the number of censored values may have disguised the streamflow-related variability for iron. The time-series model used to detect historical concentration trends also was used to evaluate sampling designs to monitor future water-quality trends. Various sampling designs were evaluated with regard to their sensitivity to detect both annual and seasonal trends during three 4-month seasons. A reasonable overall design for detecting trends for all stations and constituents consisted of eight samples per year, with monthly sampling from April to August and bimonthly sampling from Oct

  8. Effects of fault-controlled CO2 alteration on mineralogical and geomechanical properties of reservoir and seal rocks, Crystal Geyser, Green River, Utah

    NASA Astrophysics Data System (ADS)

    Major, J. R.; Eichhubl, P.; Urquhart, A.; Dewers, T. A.

    2012-12-01

    An understanding of the coupled chemical and mechanical properties of reservoir and seal units undergoing CO2 injection is critical for modeling reservoir behavior in response to the introduction of CO2. The implementation of CO2 sequestration as a mitigation strategy for climate change requires extensive risk assessment that relies heavily on computer models of subsurface reservoirs. Numerical models are fundamentally limited by the quality and validity of their input parameters. Existing models generally lack constraints on diagenesis, failing to account for the coupled geochemical or geomechanical processes that affect reservoir and seal unit properties during and after CO2 injection. For example, carbonate dissolution or precipitation after injection of CO2 into subsurface brines may significantly alter the geomechanical properties of reservoir and seal units and thus lead to solution-enhancement or self-sealing of fractures. Acidified brines may erode and breach sealing units. In addition, subcritical fracture growth enhanced by the presence of CO2 could ultimately compromise the integrity of sealing units, or enhance permeability and porosity of the reservoir itself. Such unknown responses to the introduction of CO2 can be addressed by laboratory and field-based observations and measurements. Studies of natural analogs like Crystal Geyser, Utah are thus a critical part of CO2 sequestration research. The Little Grand Wash and Salt Wash fault systems near Green River, Utah, host many fossil and active CO2 seeps, including Crystal Geyser, serving as a faulted anticline CO2 reservoir analog. The site has been extensively studied for sequestration and reservoir applications, but less attention has been paid to the diagenetic and geomechanical aspects of the fault zone. XRD analysis of reservoir and sealing rocks collected along transects across the Little Grand Wash Fault reveal mineralogical trends in the Summerville Fm (a siltstone seal unit) with calcite and smectite increasing toward to the fault, whereas illite decreases. These trends are likely the result of CO2-related diagenesis, and similar trends are also observed in sandstone units at the site. Fracture mechanics testing of unaltered and CO2-altered sandstone and siltstone samples shows that CO2-related diagenesis, which is indicated by bleaching of the Entrada Fm, has significantly decreased the fracture resistance. The subcritical fracture index is similarly affected by alteration. These compositional and mechanical changes are expected to affect the extent, geometry, and flow properties of fracture networks in CO2 sequestration systems, and thus may significantly affect reservoir and seal performance in CO2 reservoirs. This work was funded in part by the Center for Frontiers of Subsurface Energy Security, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award Number DE-SC0001114. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  9. Greenhouse gas fluxes and budget for an annual cropping system in the Red River Valley, Manitoba, Canada

    NASA Astrophysics Data System (ADS)

    Glenn, Aaron James

    Agriculture contributes significantly to national and global greenhouse gas (GHG) inventories but there is considerable control over management decisions and changes in production methods could lead to a significant reduction and possible mitigation of emissions from the sector. For example, conservation tillage practices have been suggested as a method of sequestering atmospheric carbon dioxide (CO2), however, many questions remain unanswered regarding the short-term efficacy of the production method and knowledge gaps exist regarding possible interactions with essential nutrient cycles, and the production of non-CO2 GHGs, such as nitrous oxide (N2O). Between autumn 2005 and 2009, a micrometeorological flux system was used to determine net CO2 and (N2O exchange from an annual cropping system situated on clay soil in the Red River Valley of southern Manitoba. Four plots (4-ha each) were independently evaluated and planted to corn in 2006 and faba bean in 2007; in 2008, two spring wheat plots were monitored. As well, during the non-growing season in 2006-2007 following corn harvest, a second micrometeorological flux system capable of simultaneously measuring stable C isotopologue (12CO2 and 13CO 2) fluxes was operated at the site. Tillage intensity and crop management practices were examined for their influence on GHG emissions. Significant inter-annual variability in CO2 and (N2O fluxes as a function of crop and related management activities was observed. Tillage intensity did not affect GHG emissions from the site. After accounting for harvest removals, the net ecosystem C budgets were 510 (source), 3140 (source) and -480 (sink) kg C/ha/year for the three respective crop years, summing to a three-year loss of 3170 kg C/ha. Stable C isotope flux measurements during the non-growing season following corn harvest indicated that approximately 70 % and 20 -- 30 % of the total respiration flux originated from crop residue C during the fall of 2006 and spring of 2007, respectively. The (N2O emissions at the site further exacerbated the net global warming potential of this annual agroecosystem.

  10. Environmental impact of a nuclear plant on Mississippi River biota in an ecological recovery zone near Red Wing, Minnesota. Final report

    SciTech Connect

    Dieterman, L.J.; McConville, D.R.

    1980-01-01

    The biota of the Mississippi River in an ecological recovery zone near Red Wing, MN was studied before and after start-up of a nuclear plant to acquire baseline data and to estimate changes due to thermal addition. Thermal addition produced significant decreases in primary production in a plant region during summer month periods when water temperatures were near 36C. Extensive fisheries studies and sonar tagging/tracking of S. vitreum were performed. Comparison of fisheries results with other riverine, lake, and pond studies indicated a favorable environment for the success of the fish species studied. Qualitative macroinvertebrate surveys were conducted.

  11. Continuous water-quality monitoring and regression analysis to estimate constituent concentrations and loads in the Red River of the North at Fargo and Grand Forks, North Dakota, 2003-12

    USGS Publications Warehouse

    Galloway, Joel M.

    2014-01-01

    The Red River of the North (hereafter referred to as “Red River”) Basin is an important hydrologic region where water is a valuable resource for the region’s economy. Continuous water-quality monitors have been operated by the U.S. Geological Survey, in cooperation with the North Dakota Department of Health, Minnesota Pollution Control Agency, City of Fargo, City of Moorhead, City of Grand Forks, and City of East Grand Forks at the Red River at Fargo, North Dakota, from 2003 through 2012 and at Grand Forks, N.Dak., from 2007 through 2012. The purpose of the monitoring was to provide a better understanding of the water-quality dynamics of the Red River and provide a way to track changes in water quality. Regression equations were developed that can be used to estimate concentrations and loads for dissolved solids, sulfate, chloride, nitrate plus nitrite, total phosphorus, and suspended sediment using explanatory variables such as streamflow, specific conductance, and turbidity. Specific conductance was determined to be a significant explanatory variable for estimating dissolved solids concentrations at the Red River at Fargo and Grand Forks. The regression equations provided good relations between dissolved solid concentrations and specific conductance for the Red River at Fargo and at Grand Forks, with adjusted coefficients of determination of 0.99 and 0.98, respectively. Specific conductance, log-transformed streamflow, and a seasonal component were statistically significant explanatory variables for estimating sulfate in the Red River at Fargo and Grand Forks. Regression equations provided good relations between sulfate concentrations and the explanatory variables, with adjusted coefficients of determination of 0.94 and 0.89, respectively. For the Red River at Fargo and Grand Forks, specific conductance, streamflow, and a seasonal component were statistically significant explanatory variables for estimating chloride. For the Red River at Grand Forks, a time component also was a statistically significant explanatory variable for estimating chloride. The regression equations for chloride at the Red River at Fargo provided a fair relation between chloride concentrations and the explanatory variables, with an adjusted coefficient of determination of 0.66 and the equation for the Red River at Grand Forks provided a relatively good relation between chloride concentrations and the explanatory variables, with an adjusted coefficient of determination of 0.77. Turbidity and streamflow were statistically significant explanatory variables for estimating nitrate plus nitrite concentrations at the Red River at Fargo and turbidity was the only statistically significant explanatory variable for estimating nitrate plus nitrite concentrations at Grand Forks. The regression equation for the Red River at Fargo provided a relatively poor relation between nitrate plus nitrite concentrations, turbidity, and streamflow, with an adjusted coefficient of determination of 0.46. The regression equation for the Red River at Grand Forks provided a fair relation between nitrate plus nitrite concentrations and turbidity, with an adjusted coefficient of determination of 0.73. Some of the variability that was not explained by the equations might be attributed to different sources contributing nitrates to the stream at different times. Turbidity, streamflow, and a seasonal component were statistically significant explanatory variables for estimating total phosphorus at the Red River at Fargo and Grand Forks. The regression equation for the Red River at Fargo provided a relatively fair relation between total phosphorus concentrations, turbidity, streamflow, and season, with an adjusted coefficient of determination of 0.74. The regression equation for the Red River at Grand Forks provided a good relation between total phosphorus concentrations, turbidity, streamflow, and season, with an adjusted coefficient of determination of 0.87. For the Red River at Fargo, turbidity and streamflow were statistically significant explanatory variables for estimating suspended-sediment concentrations. For the Red River at Grand Forks, turbidity was the only statistically significant explanatory variable for estimating suspended-sediment concentration. The regression equation at the Red River at Fargo provided a good relation between suspended-sediment concentration, turbidity, and streamflow, with an adjusted coefficient of determination of 0.95. The regression equation for the Red River at Grand Forks provided a good relation between suspended-sediment concentration and turbidity, with an adjusted coefficient of determination of 0.96.

  12. Transport fluxes and emission of greenhouse gases of the Middle Niger River (west Africa): disproprotionate importance of the recent red floods in the Niamey region

    NASA Astrophysics Data System (ADS)

    Darchambeau, François; Bouillon, Steven; Alhou, Bassirou; Lambert, Thibault; Borges, Alberto V.

    2014-05-01

    The Niger River is Africa's third longest river and drains an area of ~2,120,000 km². It encompasses six hydrographic regions and crosses almost all possible ecosystem zones in West Africa. Since few decades, the Middle Niger River presents a two flood hydrograph, the local flood, or red flood, occurring during the rainy season being the more pronounced one. Here, we report initial results of a monitoring campaign whereby 2-weekly samples were collected at Niamey (Niger) [2.01°E 13.57°N] between April 2011 and March 2013 for a suite of physico-chemical and biogeochemical characteristics, including total suspended matter (TSM) concentrations, concentration and stable isotope composition of particulate organic carbon (POC and δ13C-POC) and particulate nitrogen (PN and δ15N-PN), chromophoric dissolved organic matter (CDOM), dissolved organic carbon (DOC and δ13C-DOC), dissolved inorganic carbon (DIC and δ13C-DIC), concentration of greenhouse gases (GHGs) (CO2, CH4 and N2O), as well as major elements, total alkalinity, and oxygen isotope signatures of water (δ18O-H2O). This dataset allows us to construct seasonal budgets for particulate and dissolved carbon fluxes, nutrient exports, as well as a first seasonally resolved characterisation of the GHGs emitted to the atmosphere by the Middle Niger River. The red flood, concentrated on 2 months (August-September), contributed to more than 80% of the annual transport fluxes of TSM and POC and to approximately 30% of the annual transport fluxes of DIC and DOC.

  13. The Kunlun Fault

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The Kunlun fault is one of the gigantic strike-slip faults that bound the north side of Tibet. Left-lateral motion along the 1,500-kilometer (932-mile) length of the Kunlun has occurred uniformly for the last 40,000 years at a rate of 1.1 centimeter per year, creating a cumulative offset of more than 400 meters. In this image, two splays of the fault are clearly seen crossing from east to west. The northern fault juxtaposes sedimentary rocks of the mountains against alluvial fans. Its trace is also marked by lines of vegetation, which appear red in the image. The southern, younger fault cuts through the alluvium. A dark linear area in the center of the image is wet ground where groundwater has ponded against the fault. Measurements from the image of displacements of young streams that cross the fault show 15 to 75 meters (16 to 82 yards) of left-lateral offset. The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) acquired the visible light and near infrared scene on July 20, 2000. Image courtesy NASA/GSFC/MITI/ERSDAC/JAROS, and the U.S./Japan ASTER Science Team

  14. Can we follow the neotectonic activity of the Hluboká-fault by reconstructing the evolution of the Vltava river course? - Mapping of fluvial terraces around the Budejovice-basin using historic maps

    NASA Astrophysics Data System (ADS)

    Homolova, Dana; Lomax, Johanna; Prachar, Ivan; Spacek, Petr; Zamolyi, Andras; Decker, Kurt

    2010-05-01

    The Budějovice Basin in the Bohemian Massif (Czech Republic) is a fault-bounded sedimentary basin with a multiple subsidence history overlying Variscan crystalline basement. Permian, Cretaceous and Miocene sediments record repeated reactivations of faults at or close to the basin margin, which may have continued into the Quaternary. The latter is indicated by geomorphological features such as linear topographic scarps, which characterize part of the faults within and at the border of the Budějovice Basin. In a current study we assess possible Quaternary displacements along the faults delimiting the basin using geomorphological data, analyses of river planform patterns and correlations of Quaternary terraces of the Vltava River, which crosses the basin and its boundary faults. The regionally most important tectonic feature - the Hluboká fault -forms the northeastern margin of the Budějovice basin. The fault crosses the course of the river Vltava, a fact that guided our research to take a more precise look at the character and distribution of fluvial sediments in this area. Our main focus is on dating of terrace bodies around the Hluboká fault. According to the scheme used in most European regions, influences by the Pleistocene glacial cycles, the Vltava river terraces were assigned by most scientists to the 4(5) main alpine glacial periods. This dating is not straightforward as terraces are not connected to moraine bodies like in the Alps. The terraces were basically correlated by their altitude above the river and by their lithology (clastic content and grain size composition), but mostly without any numerical age determination. Our studies include several field and laboratory methods, supported by computer analyses of various types of spatial data. Data sources include: (i) modern topographic maps, (ii) geological maps, (iii) georeferenced historic map sheets of the Austrian Second Military Survey (provided by the Geoinformatics Laboratory of the University J. E. Purkyně, 2005). The georeferenced map sheets of the Second Military Survey provide a very exact base map (Timár et al., 2006) for investigating the location of possible terrace bases. Since the georeferencing accuracy is < 10 m, data from these map sheets can be integrated into the geomorphologic studies providing information about the geomorphologic situation in the study area of the years 1836-1842, i.e., with less anthropogenic impact on geomorphological features than today. These data sources are combined with data from boreholes and thus help us identifying potential terrace bodies and choosing appropriate investigation sites. In the field, morphological, sedimentological and pedological methods are used to obtain relevant data about the sediment stratigraphy. Several laboratory analyses were carried out to gain information on the age of the terraces. We use OSL-dating in combination with the analysis of heavy minerals and clay minerals, as well as grain size analysis. After gathering information about the absolute ages of the terrace bodies upstream and downstream the Hluboká fault, we may be able to declare if the building of terrace staircases was influenced by tectonic activity of the fault or not. Timár, G., Molnár, G., Székely, B., Biszak, S., Varga, J., Jankó, A. (2006): Digitized maps of the Habsburg Empire - The map sheets of the second military survey and their georeferenced version. Arcanum, Budapest, 59 p. ISBN 963-7374-33-7

  15. Calibration, verification, and use of a water-quality model to simulate effects of discharging treated wastewater to the Red River of the North at Fargo, North Dakota

    USGS Publications Warehouse

    Wesolowski, E.A.

    1994-01-01

    A 30.8-mile reach of the Red River of the North receives treated wastewater from plants at Fargo, North Dakota, and Moorhead, Minnesota, and streamflows from the Sheyenne River. A one-dimensional, steady-state, stream water-quality model, the Enhanced Stream Water Quality Model (QUAL2E), was calibrated and verified for summer stream flow conditions to simulate some of the biochemical processes that result from discharging treated wastewater into this reach of the river. Data obtained to define the river's transport conditions are measurements of channel geometry, streamflow, traveltime, specific conductance, and temperature. Data obtained to define the river's water-quality conditions are measurements of concentrations of selected water-quality constituents and estimates of various reaction coefficients. Most of the water-quality data used to calibrate and verify the model were obtained during two synoptic samplings in August 1989 and August 1990. The water-quality model simulates specific conductance, water temperature, dissolved oxygen, ultimate carbonaceous biochemical oxygen demand, total nitrite plus nitrate as nitrogen, total ammonia as nitrogen, total organic nitrogen as nitrogen, total phosphorus as phosphorus, and algal biomass as chlorophyll a. Of the nine properties and constituents that the calibrated model simulates, all except algae were verified. When increases in dissolved-oxygen concentration are considered, model sensitivity analyses indicate that dissolved-oxygen concentration is most sensitive to maximum specific algal growth rate. When decreases in dissolved-oxygen concentration are considered, model sensitivity analyses indicate that dissolved-oxygen concentration is most sensitive to point-source ammonia. Model simulations indicate nitrification and sediment oxygen demand consume most of the dissolved oxygen in the study reach. The Red River at Fargo Water-Quality Model and the verification data set, including associated reaction-coefficient values as input, were used to simulate total ammonia as nitrogen, total nitrite plus nitrate as nitrogen, 5-day carbonaceous biochemical oxygen demand, and dissolved oxygen for water-quality conditions that result from three hypothetical boundary conditions. The model was applied to various combinations of three hypothetical waste loads when the headwater stream flow was either 50 or 75 cubic feet per second, when Fargo's wastewater-treatment plant outflow was either 15 or 37.8 cubic feet per second, and when total ammonia as nitrogen concentration of the outflow was either 5, 9, or 15 milligrams per liter. For each hypothetical waste load, at least one water-quality standard for either total ammonia as nitrogen, total nitrite plus nitrate as nitrogen, or dissolved oxygen was contravened, and, for one scenario, all three standards were contravened.

  16. A new red-eyed treefrog of Agalychnis (Anura: Hylidae: Phyllomedusinae) from middle Magdalena River valley of Colombia with comments on its phylogenetic position.

    PubMed

    Rivera-Correa, Mauricio; Duarte-Cubides, Felipe; Rueda-Almonacid, José Vicente; Daza, Juan M

    2013-01-01

    We describe a new species of the charismatic red-eyed treefrogs (genus Agalychnis) from middle Magdalena River valley of Colombia (05°50'8.04"N, 74°50'16.55"W, 380 m a.s.l.). The new species is readily distinguished from all species members of the group by having orange flanks with small white warts. Phylogenetic analysis of DNA sequences of 16S rRNA gene recovered the new species as a member of the Agalychnis callidryas group. The presence of a red hue in the iris and a golden reticulated palpebral membrane, putative synapomorphies of the clade, support this hypothesis. Our analysis suggests that Agalychnis terranova sp. nov is closely related to A. callidryas from Central America and is proposed as its sister species with an uncorrected genetic distance of 5.69% between these taxa. The phylogenetic position and the geographic distribution of the new taxon add new lights to the presence of a biogeographic disjunction between Middle America lowlands, the Pacific region and Magdalena River valley of Colombia. PMID:26042285

  17. Water-Quality Data for Water- and Wastewater-Treatment Plants Along the Red River of the North, North Dakota and Minnesota, January through October 2006

    USGS Publications Warehouse

    Damschen, William C.; Hansel, John A.; Nustad, Rochelle A.

    2008-01-01

    From January through October 2006, six sets of water-quality samples were collected at 28 sites, which included inflow and outflow from seven major municipal water-treatment plants (14 sites) and influent and effluent samples from seven major municipal wastewater treatment plants (14 sites) along the Red River of the North in North Dakota and Minnesota. Samples were collected in cooperation with the Bureau of Reclamation for use in the development of return-flow boundary conditions in a 2006 water-quality model for the Red River of the North. All samples were analyzed for nutrients and major ions. For one set of effluent samples from each of the wastewater-treatment plants, water was analyzed for Eschirichia coli, fecal coliform, 20-day biochemical oxygen demand, 20-day nitrogenous biochemical oxygen demand, total organic carbon, and dissolved organic carbon. In general, results from the field equipment blank and replicate samples indicate that the overall process of sample collection, processing, and analysis did not introduce substantial contamination and that consistent results were obtained.

  18. Influence of active fault on the evolution of landscape and drainage: Evidence from lateral propagation of a branching out fault along Himalayan front and deflection of Dabka River, Kumaun Himalayas

    NASA Astrophysics Data System (ADS)

    Shah, A.; Malik, J.; Lohani, B.

    2012-04-01

    Ongoing tectonic activity along the Central Kumaun Himalaya is well revealed by the occurrence of moderate to large magnitude earthquakes as well as by the existence of the prominent tectonically controlled geomorphic indicators. Shaded-relief images created from the digital elevation models (DEMs) are helpful in indentifying faults in mountains terrains. Coupled with the detailed and high resolution CORONA and Google images, a number of active faults were mapped. These faults branch out from the Himalayan Frontal Thrust (HFT) and the Main Boundary Thrust (MBT) in the vicinity of Nainital foot hills. The compelling evidence of uplifted gravel deposits of recent alluvial fan surfaces together with the changing pattern of streams suggest that these faults are actively propagating and therefore, modifies drainage patterns. These faults are located close the major towns of Ramnagar and Kotabagh region of Nainital foothills, which are populated areas. Thus, the earthquake hazard in this region is to be reassessed.

  19. Uncertainty analysis of the simulations of effects of discharging treated wastewater to the Red River of the North at Fargo, North Dakota, and Moorhead, Minnesota

    USGS Publications Warehouse

    Wesolowski, E.A.

    1996-01-01

    Two separate studies to simulate the effects of discharging treated wastewater to the Red River of the North at Fargo, North Dakota, and Moorhead, Minnesota, have been completed. In the first study, the Red River at Fargo Water-Quality Model was calibrated and verified for ice-free conditions. In the second study, the Red River at Fargo Ice-Cover Water-Quality Model was verified for ice-cover conditions. To better understand and apply the Red River at Fargo Water-Quality Model and the Red River at Fargo Ice-Cover Water-Quality Model, the uncertainty associated with simulated constituent concentrations and property values was analyzed and quantified using the Enhanced Stream Water Quality Model-Uncertainty Analysis. The Monte Carlo simulation and first-order error analysis methods were used to analyze the uncertainty in simulated values for six constituents and properties at sites 5, 10, and 14 (upstream to downstream order). The constituents and properties analyzed for uncertainty are specific conductance, total organic nitrogen (reported as nitrogen), total ammonia (reported as nitrogen), total nitrite plus nitrate (reported as nitrogen), 5-day carbonaceous biochemical oxygen demand for ice-cover conditions and ultimate carbonaceous biochemical oxygen demand for ice-free conditions, and dissolved oxygen. Results are given in detail for both the ice-cover and ice-free conditions for specific conductance, total ammonia, and dissolved oxygen. The sensitivity and uncertainty of the simulated constituent concentrations and property values to input variables differ substantially between ice-cover and ice-free conditions. During ice-cover conditions, simulated specific-conductance values are most sensitive to the headwater-source specific- conductance values upstream of site 10 and the point-source specific-conductance values downstream of site 10. These headwater-source and point-source specific-conductance values also are the key sources of uncertainty. Simulated total ammonia concen- trations are most sensitive to the point-source total ammonia concentrations at all three sites. Other input variables that contribute substantially to the variability of simulated total ammonia concentrations are the headwater-source total ammonia and the instream reaction coefficient for biological decay of total ammonia to total nitrite. Simulated dissolved-oxygen concentrations at all three sites are most sensitive to headwater-source dissolved-oxygen concentration. This input variable is the key source of variability for simulated dissolved-oxygen concentrations at sites 5 and 10. Headwater-source and point-source dissolved-oxygen concentrations are the key sources of variability for simulated dissolved-oxygen concentrations at site 14. During ice-free conditions, simulated specific-conductance values at all three sites are most sensitive to the headwater-source specific- conductance values. Headwater-source specific- conductance values also are the key source of uncertainty. The input variables to which total ammonia and dissolved oxygen are most sensitive vary from site to site and may or may not correspond to the input variables that contribute the most to the variability. The input variables that contribute the most to the variability of simulated total ammonia concentrations are point-source total ammonia, instream reaction coefficient for biological decay of total ammonia to total nitrite, and Manning's roughness coefficient. The input variables that contribute the most to the variability of simulated dissolved-oxygen concentrations are reaeration rate, sediment oxygen demand rate, and headwater-source algae as chlorophyll a.

  20. Records of bulk organic matter and plant pigments in sediment of the "red-tide zone" adjacent to the Changjiang River estuary

    NASA Astrophysics Data System (ADS)

    Kang, Zhenjun; Yu, Rencheng; Kong, Fanzhou; Wang, Yunfeng; Gao, Yan; Chen, Jianhua; Guo, Wei; Zhou, Mingjiang

    2016-01-01

    Cultural eutrophication caused by nutrient over-enrichment in coastal waters will lead to a cascading set of ecosystem changes and deleterious ecological consequences, such as harmful algal blooms (HABs) and hypoxia. During the past two decades since the late 1990s, recurrent large-scale HABs (red tides) and an extensive hypoxic zone have been reported in the coastal waters adjacent to the Changjiang River estuary. To retrieve the history of eutrophication and its associated ecosystem changes, a sediment core was collected from the "red-tide zone" adjacent to the Changjiang River estuary. The core was dated using the 210Pb radioisotope and examined for multiple proxies, including organic carbon (OC), total nitrogen (TN), stable isotopes of C and N, and plant pigments. An apparent up-core increase of OC content was observed after the 1970s, accompanied by a rapid increase of TN. The concurrent enrichment of δ13C and increase of the C/N ratio suggested the accumulation of organic matter derived from marine primary production during this stage. The accumulation of OC after the 1970s well reflected the significant increase of primary production in the red-tide zone and probably the intensification of hypoxia as well. Plant pigments, including chlorophyll a, β-carotene, and diatoxanthin, showed similar patterns of variation to OC throughout the core, which further confirmed the important contribution of microalgae, particularly diatoms, to the deposited organic matter. Based on the variant profiles of the pigments representative of different microalgal groups, the potential changes of the phytoplankton community since the 1970s were discussed.

  1. Questa Baseline and Pre-Mining Ground-Water Quality Investigation. 24. Seismic Refraction Tomography for Volume Analysis of Saturated Alluvium in the Straight Creek Drainage and Its Confluence With Red River, Taos County, New Mexico

    USGS Publications Warehouse

    Powers, Michael H.; Burton, Bethany L.

    2007-01-01

    As part of a research effort directed by the New Mexico Environment Department to determine pre-mining water quality of the Red River at a molybdenum mining site in northern New Mexico, we used seismic refraction tomography to create subsurface compressional-wave velocity images along six lines that crossed the Straight Creek drainage and three that crossed the valley of Red River. Field work was performed in June 2002 (lines 1-4) and September 2003 (lines 5-9). We interpreted the images to determine depths to the water table and to the top of bedrock. Depths to water and bedrock in boreholes near the lines correlate well with our interpretations based on seismic data. In general, the images suggest that the alluvium in this area has a trapezoidal cross section. Using a U.S. Geological Survey digital elevation model grid of surface elevations of this region and the interpreted elevations to water table and bedrock obtained from the seismic data, we generated new models of the shape of the buried bedrock surface and the water table through surface interpolation and extrapolation. Then, using elevation differences between the two grids, we calculated volumes of dry and wet alluvium in the two drainages. The Red River alluvium is about 51 percent saturated, whereas the much smaller volume of alluvium in the tributary Straight Creek is only about 18 percent saturated. When combined with average ground-water velocity values, the information we present can be used to determine discharge of Straight Creek into Red River relative to the total discharge of Red River moving past Straight Creek. This information will contribute to more accurate models of ground-water flow, which are needed to determine the pre-mining water quality in the Red River.

  2. Magnetic properties of sediments of the Red River: Effect of sorting on the source-to-sink pathway and its implications for environmental reconstruction

    NASA Astrophysics Data System (ADS)

    Nguyen, Thi Thu Hien; Zhang, Weiguo; Li, Zhen; Li, Jie; Ge, Can; Liu, Jinyan; Bai, Xuexin; Feng, Huan; Yu, Lizhong

    2016-02-01

    We conducted a mineral magnetic study of river bank and subaqueous delta sediments from the Red River, in order to examine the role of sedimentary sorting on the variation of sedimentary magnetic properties from source to sink. The magnetic mineralogy mainly consists of magnetite and hematite. Bulk sediment particle-size variations have a strong influence on magnetic properties, with the frequently used magnetic parameters χfd%, χARM, χARM/χ, and χARM/SIRM exhibiting positive correlations with the <4 µm fraction, while S-ratios are negatively correlated with this fraction. Compared with river bank sediments and shallow shoreface (<5 m water depth) sediments, sediments from the deeper (>5 m water depth) part of the subaqueous delta have lower χ and SIRM values, a finer ferrimagnetic grain-size and higher proportions of hematite, consistent with selective loss of coarse ferrimagnetic grains on the source-to-sink pathway. We suggest that variations in magnetic properties in response to particle-size compositions and therefore depositional environment changes should be carefully addressed when magnetic proxies such as χARM/SIRM are used in the study of coastal and marine environmental changes (e.g., sea-level change). In such cases, the combined use of magnetic properties and geochemical indicators, such as Al/Ti ratio, may provide better results for paleoenvironmental reconstruction.

  3. Fault finder

    DOEpatents

    Bunch, Richard H.

    1986-01-01

    A fault finder for locating faults along a high voltage electrical transmission line. Real time monitoring of background noise and improved filtering of input signals is used to identify the occurrence of a fault. A fault is detected at both a master and remote unit spaced along the line. A master clock synchronizes operation of a similar clock at the remote unit. Both units include modulator and demodulator circuits for transmission of clock signals and data. All data is received at the master unit for processing to determine an accurate fault distance calculation.

  4. Historic and naturalized monthly streamflow for selected sites in the Red River of the North Basin in North Dakota, Minnesota, and South Dakota, 1931-2001

    USGS Publications Warehouse

    Emerson, Douglas G.

    2005-01-01

    Historic monthly streamflow data were compiled and missing historic and naturalized monthly streamflow data were estimated to develop a database of updated streamflow data for January 1931 through December 2001 (the data-development period) for 35 sites in the Red River of the North Basin. Of the 35 sites, 4 had gaged historic monthly streamflow data for the entire data-development period, 10 had gaged historic monthly streamflow data for part of the data-development period, and 21 had no gaged historic monthly streamflow data. To develop the database, a modified drainage-area ratio method, a maintenance of variance extension type 1 method, and a water-balance method were used to estimate the missing historic monthly streamflow data. Naturalized streamflow for the 35 sites was estimated by eliminating the hydrologic effects of Orwell Dam, Reservation Dam, White Rock Dam, Baldhill Dam, surfacewater withdrawals, and return flows.

  5. The highest red flood of the Niger River ever recorded at Niamey: climate change or land use change?

    NASA Astrophysics Data System (ADS)

    Descroix, L.; Genthon, P.; Amogu, O.; Rajot, J.; Sighomnou, D.

    2011-12-01

    During the summer of 2010, the middle Niger River valley suffered from a severe flood. The water reached its highest level ever recorded during a monsoon, inundating an area of about 3.1 sq.km in the city of Niamey where some 5,000 people lost their homes. Data on rainfall, on the runoff of the tributaries of the Niger River near Niamey and on Land Use Changes since the 50s in this region will be shown and analyzed. It is shown that although there was a partial recovery after the severe droughts of the 1970's and 1980's, rainfall was not the main causative factor of this exceptional flood: the annual rainfall amount for 2010 was below that of 20 other rainy seasons in the middle Niger Basin since 1950, and neither the monthly rainfall distribution, nor the rainfall amount distribution of events changed significantly in the last few decades. Rather, the Niger River's right bank tributaries have shown a sharp increase in runoff since the 1970's, which is still ongoing, and has resulted in an evolution of the Niger River's hydrograph at Niamey during the rainy season. We show that this is due to an increase of bare soils and crusted soil areas as a consequence of human pressure and/or of non reversible effects of the drought. Changes in connectivity such as endorheism bursting events caused an increase in catchment area. Policy makers should be aware of the effect of human pressure, mainly cropping and grazing, on the hydrological regimes of Sahelian rivers.

  6. LA-ICP-MS mineral chemistry of titanite and the geological implications for exploration of porphyry Cu deposits in the Jinshajiang - Red River alkaline igneous belt, SW China

    NASA Astrophysics Data System (ADS)

    Xu, Leiluo; Bi, Xianwu; Hu, Ruizhong; Tang, Yongyong; Wang, Xinsong; Xu, Yue

    2015-04-01

    The Jinshajiang-Red River alkaline igneous belt in the eastern Indian-Asian collision zone, of southwestern China, hosts abundant, economically important Cu-Mo-Au mineralization of Cenozoic age. Major- and trace-element compositions of titanites from representative Cu-mineralized intrusions determined by LA-ICP-MS show higher values for Fe2O3/Al2O3, ΣREE + Y, LREE/HREE, Ce/Ce*, (Ce/Ce*)/(Eu/Eu*), U, Th, Ta, Nb and Ga, and lower values for Al2O3, CaO, Eu/Eu*, Zr/Hf, Nb/Ta and Sr than those for titanites from barren intrusions. Different ΣREE + Y, LREE/HREE, U, Th, Ta and Nb values of titanites between Cu-mineralized and barren intrusions were controlled mainly by the coexisting melt compositions. However, different Sr concentrations and negative Eu anomalies of titanites between Cu-mineralized and barren intrusions were most probably caused by different degrees of crystallization of feldspar from melts. In addition, different Ga concentrations and positive Ce anomalies of titanites between Cu-mineralized and barren intrusions were most likely caused by different magmatic fO2 conditions. Pronounced compositional differences of titanites between Cu-mineralized and barren intrusions can provide a useful tool to help discriminate between ore-bearing and barren intrusions at an early stage of exploration, and, thus, have a potential application in exploration for porphyry Cu deposits in the Jinshajiang - Red River alkaline igneous belt, and to other areas.

  7. FOXO3 variants are beneficial for longevity in Southern Chinese living in the Red River Basin: A case-control study and meta-analysis.

    PubMed

    Sun, Liang; Hu, Caiyou; Zheng, Chenguang; Qian, Yu; Liang, Qinghua; Lv, Zeping; Huang, Zezhi; Qi, KeYan; Gong, Huan; Zhang, Zheng; Huang, Jin; Zhou, Qin; Yang, Ze

    2015-01-01

    Forkhead box class O (FOXO) transcription factors play a crucial role in longevity across species. Several polymorphisms in FOXO3 were previously reported to be associated with human longevity. However, only one Chinese replication study has been performed so far. To verify the role of FOXO3 in southern Chinese in the Red River Basin, a community-based case-control study was conducted, and seven polymorphisms were genotyped in 1336 participants, followed by a meta-analysis of eight case-control studies that included 5327 longevity cases and 4608 controls. In our case-control study, we found rs2802288*A and rs2802292*G were beneficial to longevity after Bonferroni correction (pallele = 0.005, OR = 1.266; pallele = 0.026, OR = 1.207). In addition, in the longevity group, carriers with rs2802288*A and rs2802292*G presented reduced HbA1c (p = 0.001), and homozygotes of rs2802292*GG presented improved HOMA-IR (p = 0.014). The meta-analysis further revealed the overall contribution of rs2802288*A and rs2802292*G to longevity. However, our stratified analysis revealed that rs2802292*G might act more strongly in Asians than Europeans, for enhancement of longevity. In conclusion, our study provides convincing evidence for a significant association between the rs2802288*A and rs2802292*G gene variants in FOXO3 and human longevity, and adds the Southern Chinese in the Red River Basin to the growing number of human replication populations. PMID:25913413

  8. Genetic diversity among red swamp crayfish (Procambarus clarkii) populations in the middle and lower reaches of the Yangtze River based on AFLP markers.

    PubMed

    Zhu, B F; Huang, Y; Dai, Y G; Bi, C W; Hu, C Y

    2013-01-01

    The red swamp crayfish has become one of the most important freshwater aquaculture species in China. At present, although it is widely distributed in the middle and lower reaches of the Yangze River basin, little is known about its population genetics and geographic distribution in China. We estimated the genetic diversity among 6 crayfish populations from 4 lakes (Hongze Lake, Poyang Lake, Dongting Lake, and Yue Lake) using AFLPs. A total of 129 loci were generated with 5 EcoRI-MseI primer combinations and scored as binary data in 139 individuals. These data were analyzed by cluster methods with the NTSYSpc software package. The 6 populations were separated into 3 major clusters by principal coordinate analysis and cluster analysis. Among the 6 populations, the highest gene diversity was found within the Nanjing population. Analysis of molecular variance demonstrated that most variation occurred within populations (91.20%). The estimated average GST value across all loci was 0.4186, suggesting (very) low gene flow among the different localities. We conclude that there is high genetic differentiation among crayfish in the middle and lower reaches of the Yangze River. This information will help in the selection of high-quality individuals for artificial reproduction. PMID:23546963

  9. Fault tectonics and earthquake hazards in the Peninsular Ranges, Southern California. [including San Diego River, Otay Mts., Japatul Valley, Barrett Lake, Horsethief Canyon, Pine Valley Creek, Pine Creek, and Mojave Desert

    NASA Technical Reports Server (NTRS)

    Merifield, P. M. (Principal Investigator)

    1975-01-01

    The author has identified the following significant results. Thin sections of rock exposed along the San Diego River linear were prepared and determined to be fault breccia. Single band and ratio images of the western Mojave Desert were prepared from the multispectral scanner digital tapes. Subtle differences in color of soil and rock are enhanced on the ratio images. Two north-northeast trending linears (Horsethief Canyon and Pine Valley Creek) and an east-west linear (Pine Creek) were concluded to have resulted from erosion along well-developed foliation in crystalline basement rocks.

  10. Automatic distribution fault locating system

    SciTech Connect

    Hager, G.E.; Bear, R.N.M.; Baum, A.S.

    1995-12-31

    An automated fault locating system was designed and implemented for the Colorado River Agency (CRA) 12.5/7.2 kV distribution system. This automated fault locating system (FLS) was integrated into the Supervisory Control and Data Acquisition (SCADA) system which was installed at a hydro power plant. This FLS offers several benefits to the CRA distribution system. These benefits include: reduced outage time; help in locating momentary faults; enhanced safety to the line crews; provide notification of an outage without receiving calls from the consumer; and decreased overtime.

  11. Depth Transects of Sediment Age, Reflectance, and Aquifer Arsenic in the Bac Bo Plain, Vietnam: Implications for Groundwater Arsenic Heterogeneity in the Red River Delta

    NASA Astrophysics Data System (ADS)

    Weinman, B.; Goodbred, S. L.; Radloff, K.; Aziz, Z.; Jung, H.; Frei, F.; Berg, M.; Trang, P. K.; Singhvi, A.; van Geen, A.

    2007-12-01

    Shallow aquifer groundwater arsenic heterogeneity is well documented in many of the fluvial regions of Asia. To this day, the cause for the heterogeneity remains poorly understood in part because of the heterogeneity of sediment properties inherent to a young floodplain depositional environment. In April 2006, a needle-sampler device was used to obtain depth transects of both sediment and porewater samples as the first step towards understanding the heterogeneous subsurface environment. Depth transects were taken between sites with opposing trends in tube-well arsenic, e.g. low As cluster to high As cluster, in a stable, fault controlled river bend in Van Phuc, Vietnam, to determine how sediment properties such as grainsize and reflectance relate to dissolved arsenic. Luminescence dating of aquifer sands and He3/H3 dating of the groundwater was conducted to investigate how aquifer redox conditions and groundwater arsenic evolve in Van Phuc's river-bend over time. Results indicate that localized zones of sediments enriched in leachable arsenic exist at depth within the aquifer and provide a mostly local source of arsenic. It also appears that groundwater flow encountering sediments of different ages can account for some of the observed spatial patterns of groundwater heterogeneity. Compiled with observations that reducing groundwaters with both low dissolved and extractable arsenic exist in the upper deltaic region, it appears that heterogeneities in shallow floodplain arsenic can be driven by magnitude differences in sediment-labile arsenic. Finally, given that these localized packages of arsenic enrichment correspond to a particular in-filling type of facies, it appears that fluvial cycling along the delta is the underlying cause of arsenic heterogeneity in the shallow floodplain.

  12. Myrionecta Rubra Population Genetic Diversity and Its Cryptophyte Chloroplast Specificity in Recurrent Red Tides in the Columbia River Estuary

    SciTech Connect

    Herfort, Lydie; Peterson, Tawnya D.; McCue, Lee Ann; Crump, Byron C.; Prahl, Fredrick G.; Baptista, Antonio M.; Campbell, Victoria; Warnick, Rachel; Selby, Mikaela; Roegner, G. Curtis; Zuber, Peter A.

    2011-01-04

    For at least a decade, annually recurring blooms of the photosynthetic ciliate, Myrionecta rubra have been observed in the Columbia River estuary in late summer. In an effort to understand the dynamics of these blooms, we investigated the genetic variability of M. rubra and its cryptophyte plastids within three large estuarine blooms formed in consecutive years (2007-2009), and conducted a broader spatial survey along the coasts of Oregon/Washington. Analysis of the ‘18S-28S’ sequences specific for Mesodiniidae uncovered at least 7 variants of M. rubra within the Columbia River coastal margin in spring and summer, but only one of these M. rubra variants was implicated in estuary bloom formation. Using a multigene approach, we show that the bloom-forming variant of M. rubra appears to harbor the same cryptophyte chloroplast in recurring blooms. Analyses of chloroplast 16S rRNA, cryptophyte RuBisCO and Photosystem II D2 genes together suggest that the plastid is derived from Teleaulax amphioxeia. Free-living cells of this species and of other cryptophytes were practically absent from the bloom patches in the estuary main channels based on 18S rDNA sequence analyses. The respectively low and high proportions of T. amphioxeia nuclei and chloroplasts signals found in the M. rubra bloom of the Columbia River estuary in successive years supports the notion of a transient association between T. amphioxeia and the bloom-forming M. rubra variant, with loss of cryptophyte nuclei. The genetic variability of M. rubra uncovered here is relevant to the controversy in the literature regarding the cryptophyte /M. rubra association.

  13. Tracing the Geomorphic Signature of Lateral Faulting

    NASA Astrophysics Data System (ADS)

    Duvall, A. R.; Tucker, G. E.

    2012-12-01

    Active strike-slip faults are among the most dangerous geologic features on Earth. Unfortunately, it is challenging to estimate their slip rates, seismic hazard, and evolution over a range of timescales. An under-exploited tool in strike-slip fault characterization is quantitative analysis of the geomorphic response to lateral fault motion to extract tectonic information directly from the landscape. Past geomorphic work of this kind has focused almost exclusively on vertical motion, despite the ubiquity of horizontal motion in crustal deformation and mountain building. We seek to address this problem by investigating the landscape response to strike-slip faulting in two ways: 1) examining the geomorphology of the Marlborough Fault System (MFS), a suite of parallel strike-slip faults within the actively deforming South Island of New Zealand, and 2) conducting controlled experiments in strike-slip landscape evolution using the CHILD landscape evolution model. The MFS offers an excellent natural experiment site because fault initiation ages and cumulative displacements decrease from north to south, whereas slip rates increase over four fold across a region underlain by a single bedrock unit (Torlesse Greywacke). Comparison of planform and longitudinal profiles of rivers draining the MFS reveals strong disequilibrium within tributaries that drain to active fault strands, and suggests that river capture related to fault activity may be a regular process in strike-slip fault zones. Simple model experiments support this view. Model calculations that include horizontal motion as well as vertical uplift demonstrate river lengthening and shortening due to stream capture in response to shutter ridges sliding in front of stream outlets. These results suggest that systematic variability in fluvial knickpoint location, drainage area, and incision rates along different faults or fault segments may be expected in catchments upstream of strike-slip faults and could act as useful indicators of fault activity.

  14. Active Features of Guguan-Guizhen Fault at the Northeast Margin of Qinghai-Tibet Block since Late Quaternary

    NASA Astrophysics Data System (ADS)

    Shi, Yaqin; Feng, Xijie; Li, Gaoyang; Ma, Ji; Li, Miao; Zhang, Yi

    2015-04-01

    Guguan-Guizhen fault is located at the northeast margin of Qinghai-Tibet Block and northwest margin of Ordos Block; it is the boundary of the two blocks, and one of the multiple faults of northwest Haiyuan-Liupanshan-Baoji fault zone. Guguan-Guizhen fault starts from Putuo Village, Huating County, Gansu Province, and goes through Badu Town, Long County in Shaanxi Province ends in Guozhen Town in Baoji City, Shaanxi Province. The fault has a full length of about 130km with the strike of 310-330°, the dip of SW and the rake of 50-60°, which is a sinistral slip reverse fault in the north part, and a sinistral slip normal fault in the southeast part. Guguan-Guizhen fault has a clear liner structure in satellite images and significant landform elevation difference with a maximum difference of 80m, and is higher in the east lower in the west. The northwest side of Guguan-Guizhen fault is composed of purplish-red Lower Cretaceous sandstones and river terrace; the northeast side is composed of Ordovician Limestone. Shigou, Piliang, Songjiashan, Tianjiagou and Chenjiagou fault profiles are found to the south of Badu Village. After 14C and optically stimulated luminescence dating, the fault does not dislocate the stratum since late Pleistocene (90.5±4.4ka) in Shigou, Piliang and Songjiashan fault profiles, and does not dislocate the cobble layer of Holocene first terrace and recent sliderock (3180±30 BP). But the fault dislocated the stratum of middle Pleistocene in some of the fault profiles. All the evidences above indicate that the fault is active in middle Pleistocene, and being silence since late Pleistocene. It might be active in Holocene to the north of Badu Village due to collapses are found in a certain area. The cause of these collapses is Qinlong M6-7 earthquake in 600 A.D., and might be relevant with Guguan-Guizhen fault after analysis of the scale, feature and age determination of the collapse. If any seismic surface rupture and ancient earthquake traces exist is still in researching. This study has a significant meaning of major earthquake risk analysis at the northeast margin of Qinghai-Tibet Block.

  15. A Multi-Scale Approach to Investigating the Red-Crowned Crane–Habitat Relationship in the Yellow River Delta Nature Reserve, China: Implications for Conservation

    PubMed Central

    Cao, Mingchang; Xu, Haigen; Le, Zhifang; Zhu, Mingchang; Cao, Yun

    2015-01-01

    The red-crowned crane (Grus japonensis (Statius Müller, 1776)) is a rare and endangered species that lives in wetlands. In this study, we used variance partitioning and hierarchical partitioning methods to explore the red-crowned crane–habitat relationship at multiple scales in the Yellow River Delta Nature Reserve (YRDNR). In addition, we used habitat modeling to identify the cranes’ habitat distribution pattern and protection gaps in the YRDNR. The variance partitioning results showed that habitat variables accounted for a substantially larger total and pure variation in crane occupancy than the variation accounted for by spatial variables at the first level. Landscape factors had the largest total (45.13%) and independent effects (17.42%) at the second level. The hierarchical partitioning results showed that the percentage of seepweed tidal flats were the main limiting factor at the landscape scale. Vegetation coverage contributed the greatest independent explanatory power at the plot scale, and patch area was the predominant factor at the patch scale. Our habitat modeling results showed that crane suitable habitat covered more than 26% of the reserve area and that there remained a large protection gap with an area of 20,455 ha, which accounted for 69.51% of the total suitable habitat of cranes. Our study indicates that landscape and plot factors make a relatively large contribution to crane occupancy and that the focus of conservation effects should be directed toward landscape- and plot-level factors by enhancing the protection of seepweed tidal flats, tamarisk-seepweed tidal flats, reed marshes and other natural wetlands. We propose that efforts should be made to strengthen wetland restoration, adjust functional zoning maps, and improve the management of human disturbance in the YRDNR. PMID:26065417

  16. A Multi-Scale Approach to Investigating the Red-Crowned Crane-Habitat Relationship in the Yellow River Delta Nature Reserve, China: Implications for Conservation.

    PubMed

    Cao, Mingchang; Xu, Haigen; Le, Zhifang; Zhu, Mingchang; Cao, Yun

    2015-01-01

    The red-crowned crane (Grus japonensis (Statius Müller, 1776)) is a rare and endangered species that lives in wetlands. In this study, we used variance partitioning and hierarchical partitioning methods to explore the red-crowned crane-habitat relationship at multiple scales in the Yellow River Delta Nature Reserve (YRDNR). In addition, we used habitat modeling to identify the cranes' habitat distribution pattern and protection gaps in the YRDNR. The variance partitioning results showed that habitat variables accounted for a substantially larger total and pure variation in crane occupancy than the variation accounted for by spatial variables at the first level. Landscape factors had the largest total (45.13%) and independent effects (17.42%) at the second level. The hierarchical partitioning results showed that the percentage of seepweed tidal flats were the main limiting factor at the landscape scale. Vegetation coverage contributed the greatest independent explanatory power at the plot scale, and patch area was the predominant factor at the patch scale. Our habitat modeling results showed that crane suitable habitat covered more than 26% of the reserve area and that there remained a large protection gap with an area of 20,455 ha, which accounted for 69.51% of the total suitable habitat of cranes. Our study indicates that landscape and plot factors make a relatively large contribution to crane occupancy and that the focus of conservation effects should be directed toward landscape- and plot-level factors by enhancing the protection of seepweed tidal flats, tamarisk-seepweed tidal flats, reed marshes and other natural wetlands. We propose that efforts should be made to strengthen wetland restoration, adjust functional zoning maps, and improve the management of human disturbance in the YRDNR. PMID:26065417

  17. Surface complexation modeling of groundwater arsenic mobility: Results of a forced gradient experiment in a Red River flood plain aquifer, Vietnam

    NASA Astrophysics Data System (ADS)

    Jessen, Søren; Postma, Dieke; Larsen, Flemming; Nhan, Pham Quy; Hoa, Le Quynh; Trang, Pham Thi Kim; Long, Tran Vu; Viet, Pham Hung; Jakobsen, Rasmus

    2012-12-01

    Three surface complexation models (SCMs) developed for, respectively, ferrihydrite, goethite and sorption data for a Pleistocene oxidized aquifer sediment from Bangladesh were used to explore the effect of multicomponent adsorption processes on As mobility in a reduced Holocene floodplain aquifer along the Red River, Vietnam. The SCMs for ferrihydrite and goethite yielded very different results. The ferrihydrite SCM favors As(III) over As(V) and has carbonate and silica species as the main competitors for surface sites. In contrast, the goethite SCM has a greater affinity for As(V) over As(III) while PO43- and Fe(II) form the predominant surface species. The SCM for Pleistocene aquifer sediment resembles most the goethite SCM but shows more Si sorption. Compiled As(III) adsorption data for Holocene sediment was also well described by the SCM determined for Pleistocene aquifer sediment, suggesting a comparable As(III) affinity of Holocene and Pleistocene aquifer sediments. A forced gradient field experiment was conducted in a bank aquifer adjacent to a tributary channel to the Red River, and the passage in the aquifer of mixed groundwater containing up to 74% channel water was observed. The concentrations of As (<0.013 μM) and major ions in the channel water are low compared to those in the pristine groundwater in the adjacent bank aquifer, which had an As concentration of ˜3 μM. Calculations for conservative mixing of channel and groundwater could explain the observed variation in concentration for most elements. However, the mixed waters did contain an excess of As(III), PO43- and Si which is attributed to desorption from the aquifer sediment. The three SCMs were tested on their ability to model the desorption of As(III), PO43- and Si. Qualitatively, the ferrihydrite SCM correctly predicts desorption for As(III) but for Si and PO43- it predicts an increased adsorption instead of desorption. The goethite SCM correctly predicts desorption of both As(III) and PO43- but failed in the prediction of Si desorption. These results indicate that the prediction of As mobility, by using SCMs for synthetic Fe-oxides, will be strongly dependent on the model chosen. The SCM based on the Pleistocene aquifer sediment predicts the desorption of As(III), PO43- and Si quite superiorly, as compared to the SCMs for ferrihydrite and goethite, even though Si desorption is still somewhat under-predicted. The observation that a SCM calibrated on a different sediment can predict our field results so well suggests that sediment based SCMs may be a feasible way to model multi-component adsorption in aquifers.

  18. Fault diagnosis

    NASA Technical Reports Server (NTRS)

    Abbott, Kathy

    1990-01-01

    The objective of the research in this area of fault management is to develop and implement a decision aiding concept for diagnosing faults, especially faults which are difficult for pilots to identify, and to develop methods for presenting the diagnosis information to the flight crew in a timely and comprehensible manner. The requirements for the diagnosis concept were identified by interviewing pilots, analyzing actual incident and accident cases, and examining psychology literature on how humans perform diagnosis. The diagnosis decision aiding concept developed based on those requirements takes abnormal sensor readings as input, as identified by a fault monitor. Based on these abnormal sensor readings, the diagnosis concept identifies the cause or source of the fault and all components affected by the fault. This concept was implemented for diagnosis of aircraft propulsion and hydraulic subsystems in a computer program called Draphys (Diagnostic Reasoning About Physical Systems). Draphys is unique in two important ways. First, it uses models of both functional and physical relationships in the subsystems. Using both models enables the diagnostic reasoning to identify the fault propagation as the faulted system continues to operate, and to diagnose physical damage. Draphys also reasons about behavior of the faulted system over time, to eliminate possibilities as more information becomes available, and to update the system status as more components are affected by the fault. The crew interface research is examining display issues associated with presenting diagnosis information to the flight crew. One study examined issues for presenting system status information. One lesson learned from that study was that pilots found fault situations to be more complex if they involved multiple subsystems. Another was pilots could identify the faulted systems more quickly if the system status was presented in pictorial or text format. Another study is currently under way to examine pilot mental models of the aircraft subsystems and their use in diagnosis tasks. Future research plans include piloted simulation evaluation of the diagnosis decision aiding concepts and crew interface issues. Information is given in viewgraph form.

  19. Quantifying water requirements of riparian river red gum (Eucalyptus camaldulensis) in the Murray-Darling Basin, Australia: implications for the management of environmental flows

    USGS Publications Warehouse

    Doody, Tanya M.; Colloff, Matthew J.; Davies, Micah; Koul, Vijay; Benyon, Richard G.; Nagler, Pamela L.

    2015-01-01

    Water resource development and drought have altered river flow regimes, increasing average flood return intervals across floodplains in the Murray-Darling Basin, Australia, causing health declines in riparian river red gum (Eucalyptus camaldulensis) forests and woodlands. Environmental flow allocations helped to alleviate water stress during the recent Millennium Drought (1997–2010), however, quantification of the flood frequency required to support healthy E. camaldulensis communities is still needed. We quantified water requirements of E. camaldulensis for two years across a flood gradient (trees inundated at frequencies of 1:2, 1:5 and 1:10 years) at Yanga National Park, New South Wales to help inform management decision-making and design of environmental flows. Sap flow, evaporative losses and soil moisture measurements were used to determine transpiration, evapotranspiration and plant-available soil water before and after flooding. A formula was developed using plant-available soil water post-flooding and average annual rainfall, to estimate maintenance time of soil water reserves in each flood frequency zone. Results indicated that soil water reserves could sustain 1:2 and 1:5 trees for 15 months and six years, respectively. Trees regulated their transpiration rates, allowing them to persist within their flood frequency zone, and showed reduction in active sapwood area and transpiration rates when flood frequencies exceeded 1:2 years. A leaf area index of 0.5 was identified as a potential threshold indicator of severe drought stress. Our results suggest environmental water managers may have greater flexibility to adaptively manage floodplains in order to sustain E. camaldulensis forests and woodlands than has been appreciated hitherto.

  20. Active fault traces along Bhuj Fault and Katrol Hill Fault, and trenching survey at Wandhay, Kachchh, Gujarat, India

    NASA Astrophysics Data System (ADS)

    Morino, Michio; Malik, Javed N.; Mishra, Prashant; Bhuiyan, Chandrashekhar; Kaneko, Fumio

    2008-06-01

    Several new active fault traces were identified along Katrol Hill Fault (KHF). A new fault (named as Bhuj Fault, BF) that extends into the Bhuj Plain was also identified. These fault traces were identified based on satellite photo interpretation and field survey. Trenches were excavated to identify the paleoseismic events, pattern of faulting and the nature of deformation. New active fault traces were recognized about 1km north of the topographic boundary between the Katrol Hill and the plain area. The fault exposure along the left bank of Khari River with 10m wide shear zone in the Mesozoic rocks and showing displacement of the overlying Quaternary deposits is indicative of continued tectonic activity along the ancient fault. The E-W trending active fault traces along the KHF in the western part changes to NE-SW or ENE-WSW near Wandhay village. Trenching survey across a low scarp near Wandhay village reveals three major fault strands F1, F2, and F3. These fault strands displaced the older terrace deposits comprising Sand, Silt and Gravel units along with overlying younger deposits from units 1 to 5 made of gravel, sand and silt. Stratigraphic relationship indicates at least three large magnitude earthquakes along KHF during Late Holocene or recent historic past.

  1. Fault mechanics

    SciTech Connect

    Segall, P. )

    1991-01-01

    Recent observational, experimental, and theoretical modeling studies of fault mechanics are discussed in a critical review of U.S. research from the period 1987-1990. Topics examined include interseismic strain accumulation, coseismic deformation, postseismic deformation, and the earthquake cycle; long-term deformation; fault friction and the instability mechanism; pore pressure and normal stress effects; instability models; strain measurements prior to earthquakes; stochastic modeling of earthquakes; and deep-focus earthquakes. Maps, graphs, and a comprehensive bibliography are provided. 220 refs.

  2. Genetic differentiation in the populations of red piranha, Pygocentrus nattereri Kner (1860) (Characiformes: Serrasalminae), from the river basins of northeastern Brazil.

    PubMed

    Luz, L A; Reis, L L; Sampaio, I; Barros, M C; Fraga, E

    2015-11-01

    The red piranha, Pygocentrus nattereri, is an important resource for artisanal and commercial fisheries. The present study determines the genetic differentiation among P. nattereri populations from the northeastern Brazilian state of Maranhão. The DNA was isolated using a standard phenol-chloroform protocol and the Control Region was amplified by PCR. The PCR products were sequenced using the didesoxyterminal method. A sequence of 1039 bps was obtained from the Control Region of 60 specimens, which presented 33 polymorphic sites, 41 haplotypes, һ =0.978 and π =0.009. The neutrality tests (D and Fs) were significant (P < 0.05) for most of the populations analyzed. The AMOVA indicated that most of the molecular variation (72%) arises between groups. The fixation index was highly significant (FST = 0.707, P < 0.00001). The phylogenetic analyses indicated that the specimens represented a monophyletic group. Genetic distances between populations varied from 0.8% to 1.9%, and were <0.5% within populations. The degree of genetic differentiation found among the stocks of P. nattereri indicates the need for the development of independent management plans for the different river basins in order to preserve the genetic variability of their populations. PMID:26675902

  3. Temporal change and its spatial variety on land surface temperature and land use changes in the Red River Delta, Vietnam, using MODIS time-series imagery.

    PubMed

    Van Nguyen, On; Kawamura, Kensuke; Trong, Dung Phan; Gong, Zhe; Suwandana, Endan

    2015-07-01

    Temporal changes in the land surface temperature (LST) in urbanization areas are important for studying an urban heat island (UHI) and regional climate change. This study examined the LST trends under different land use categories in the Red River Delta, Vietnam, using the Moderate Resolution Imaging Spectroradiometer (MODIS) LST product (MOD11A2) and land cover type product (MCD12Q1) for 11years (2002-2012). Smoothened time-series MODIS LST data were reconstructed by the Harmonic Analysis of Time Series (HANTS) algorithm. The reconstructed LST (maximum and minimum temperatures) was assessed using the hourly air temperature dataset in two land-based meteorological stations provided by the National Climatic Data Center (NCDC). Significant correlation was obtained between MODIS LST and the air temperature for the daytime (R (2)?=?0.73, root mean square error [RMSE]?=?1.66C) and night time (R (2)?=?0.84, RMSE?=?1.79C). Statistical analysis also showed that LST trends vary strongly depending on the land cover type. Forest, wetland, and cropland had a slight tendency to decline, whereas cropland and urban had sharper increases. In urbanized areas, these increasing trends are even more obvious. This is undeniable evidence of the negative impact of urbanization on a surface urban heat island (SUHI) and global warming. PMID:26113204

  4. Evaluation of drainage-area ratio method used to estimate streamflow for the Red River of the North Basin, North Dakota and Minnesota

    USGS Publications Warehouse

    Emerson, Douglas G.; Vecchia, Aldo V.; Dahl, Ann L.

    2005-01-01

    The drainage-area ratio method commonly is used to estimate streamflow for sites where no streamflow data were collected. To evaluate the validity of the drainage-area ratio method and to determine if an improved method could be developed to estimate streamflow, a multiple-regression technique was used to determine if drainage area, main channel slope, and precipitation were significant variables for estimating streamflow in the Red River of the North Basin. A separate regression analysis was performed for streamflow for each of three seasons-- winter, spring, and summer. Drainage area and summer precipitation were the most significant variables. However, the regression equations generally overestimated streamflows for North Dakota stations and underestimated streamflows for Minnesota stations. To correct the bias in the residuals for the two groups of stations, indicator variables were included to allow both the intercept and the coefficient for the logarithm of drainage area to depend on the group. Drainage area was the only significant variable in the revised regression equations. The exponents for the drainage-area ratio were 0.85 for the winter season, 0.91 for the spring season, and 1.02 for the summer season.

  5. The Project for Intercomparison of Land-surface Parameterization Schemes (PILPS) phase 2(c) Red-Arkansas River basin experiment:. 2. Spatial and temporal analysis of energy fluxes

    NASA Astrophysics Data System (ADS)

    Liang, Xu; Wood, Eric F.; Lettenmaier, Dennis P.; Lohmann, Dag; Boone, Aaron; Chang, Sam; Chen, Fei; Dai, Yongjiu; Desborough, Carl; Dickinson, Robert E.; Duan, Qingyun; Ek, Michael; Gusev, Yeugeniy M.; Habets, Florence; Irannejad, Parviz; Koster, Randy; Mitchell, Kenneth E.; Nasonova, Olga N.; Noilhan, Joel; Schaake, John; Schlosser, Adam; Shao, Yaping; Shmakin, Andrey B.; Verseghy, Diana; Warrach, Kirsten; Wetzel, Peter; Xue, Yongkang; Yang, Zong-Liang; Zeng, Qing-cun

    1998-12-01

    The energy components of sixteen Soil-Vegetation Atmospheric Transfer (SVAT) schemes were analyzed and intercompared using 10 years of surface meteorological and radiative forcing data from the Red-Arkansas River basin in the Southern Great Plains of the United States. Comparisons of simulated surface energy fluxes among models showed that the net radiation and surface temperature generally had the best agreement among the schemes. On an average (annual and monthly) basis, the estimated latent heat fluxes agreed (to within approximate estimation errors) with the latent heat fluxes derived from a radiosonde-based atmospheric budget method for slightly more than half of the schemes. The sensible heat fluxes had larger differences among the schemes than did the latent heat fluxes, and the model-simulated ground heat fluxes had large variations among the schemes. The spatial patterns of the model-computed net radiation and surface temperature were generally similar among the schemes, and appear reasonable and consistent with observations of related variables, such as surface air temperature. The spatial mean patterns of latent and sensible heat fluxes were less similar than for net radiation, and the spatial patterns of the ground heat flux vary greatly among the 16 schemes. Generally, there is less similarity among the models in the temporal (interannual) variability of surface fluxes and temperature than there is in the mean fields, even for schemes with similar mean fields.

  6. Complementing data-driven and physically-based approaches for predictive morphologic modeling: Results and implication from the Red River Basin, Vietnam

    NASA Astrophysics Data System (ADS)

    Schmitt, R. J.; Bernardi, D.; Bizzi, S.; Castelletti, A.; Soncini-Sessa, R.

    2013-12-01

    During the last 30 years, the delta of the Red River (Song Hong) in northern Vietnam experienced grave morphologic degradation processes which severely impact economic activities and endanger region-wide livelihoods. Rapidly progressing river bed incision, for example, threatens the irrigation of the delta's paddy rice crops which constitute 20% of Vietnam's annual rice production. Morphologic alteration is related to a drastically changed sediment balance due to major upstream impoundments, sediment mining and land use changes, further aggravated by changing hydro-meteorological conditions. Despite the severe impacts, river morphology was so far not included into the current efforts to optimize basin wide water resource planning for a lack of suitable, not overly resource demanding modeling strategies. This paper assesses the suitability of data-driven models to provide insights into complex hydromorphologic processes and to complement and enrich physically-based modeling strategies. Hence, to identify key drivers of morphological change while evaluating impacts of future socio-economic, management and climate scenarios on river morphology and the resulting effects on key social needs (e.g. water supply, energy production and flood mitigation). Most relevant drivers and time-scales for the considered processes (e.g. incision) - from days to decades - were identified from hydrologic and sedimentologic time-series using a feature ranking algorithm based on random trees. The feature ranking pointed out bimodal response characteristics, with important contributions of long-to-medium (5 - 15 yrs.) and rather short (10d - 6 months) timescales. An artificial neural network (ANN), built from identified variables, subsequently quantified in detail how these temporal components control long term trends, inter-seasonal fluctuations and day to day variations in morphologic processes. Whereas the general trajectory of incision relates, for example, to the overall regional sediment balance over an extended time-horizon (>15 yrs.), upstream impoundments induce a much more rapid adaptation (1-5 yrs.). The applicability of the ANN as predictive model was evaluated by comparing its results with a traditional, 1D bed evolution model. The next decade's morphologic evolution under an ensemble of scenarios, considering uncertainties in climatic change, socio-economic development and upstream reservoir release policies was derived from both models. The ANN greatly outperforms the 1D model in computational requirements and presents a powerful tool for effective assessment of scenario ensembles and quantification of uncertainties in river hydro-morphology. In contrast, the processes-based model provides detailed, spatio-temporally distributed outputs and validation of the ANN's results for selected scenarios. We conclude that the application of both approaches constitutes a mutually enriching strategy for modern, quantitative catchment management. We argue that physically based modeling can have specific spatial and temporal constrains (e.g. in terms of identifying key drivers and associated temporal and spatial domains) and that linking physically-based with data-driven approaches largely increases the potential for including hydro-morphology into basin-scale water resource management.

  7. Hydrogeology and sources of recharge to the Buffalo and Wahpeton aquifers in the southern part of the Red River of the North drainage basin, west-central Minnesota and southeastern North Dakota

    USGS Publications Warehouse

    Schoenberg, Michael

    1998-01-01

    The potential sources of recharge to the Wahpeton aquifers investigated were the Red River of the North, and adjacent hydro geologic units. The volume of ground water pumped from the Wahpeton aquifers provides an estimate of the upper limit for the volume of recharge to the aquifer. Based on pumpage from all of the Wapheton aquifers from 1990 to 1993, the upper limit is about 580 million gallons per year (2.4 x 105 cubic feet per day).

  8. Regression Equations for Estimating Concentrations of Selected Water-Quality Constituents for Selected Gaging Stations in the Red River of the North Basin, North Dakota, Minnesota, and South Dakota

    USGS Publications Warehouse

    Williams-Sether, Tara

    2004-01-01

    The Dakota Water Resources Act, passed by the U.S. Congress on December 15, 2000, authorized the Secretary of the Interior to conduct a comprehensive study of future water-quantity and quality needs of the Red River of the North Basin in North Dakota and possible options to meet those water needs. Previous Red River of the North Basin studies conducted by the Bureau of Reclamation used streamflow and water-quality data bases developed by the U.S. Geological Survey that included data for 1931-84. As a result of the recent congressional authorization and results of previous studies by the Bureau of Reclamation, redevelopment of the streamflow and water-quality data bases with current data through 1999 are needed in order to evaluate and predict the water-quantity and quality effects within the Red River of the North Basin. This report provides updated statistical summaries of selected water-quality constituents and streamflow and the regression relations between them. Available data for 1931-99 were used to develop regression equations between 5 selected water-quality constituents and streamflow for 38 gaging stations in the Red River of the North Basin. The water-quality constituents that were regressed against streamflow were hardness (as CaCO3), sodium, chloride, sulfate, and dissolved solids. Statistical summaries of the selected water-quality constituents and streamflow for the gaging stations used in the regression equations development and the applications and limitations of the regression equations are presented in this report.

  9. Sinuosity and meander belt scarring: Tectonics and stream dynamics across the Baton Rouge Fault Zone

    NASA Astrophysics Data System (ADS)

    Dunek, P.; Gasparini, N.

    2009-12-01

    This study focuses on the sinuosity of alluvial rivers flowing across the Baton Rogue fault zone (BRFZ). The BRFZ is a little studied normal fault system extending roughly from Baton Rogue, LA east to about the Mississippi border. We hypothesize that the sinuosity is measurably different in channel reaches upstream and downstream of the fault trace. To gather sinuosity data we use two methods. The first is field surveying using a laser range finder and GPS; this method is only used over limited reaches, because covering the entire river system in this way is prohibitively time consuming. The second method uses ArcGIS to analyze LIDAR data that are freely available for the entire state of Louisiana. The LIDAR data have a 5 meter resolution. The largest channels are easily identified by eye in the LIDAR data and can be digitally traced by hand. On most of the smaller rivers, however, it is difficult to discern the exact trace of the channel. In these cases we use the ArcGIS hydrology tools to determine the path of the rivers. In order to check the accuracy we do this twice, once with the LIDAR data and once with the USGS 10 m data. However, the two data sets often produce very different river paths. Upon further investigation it appears that the rivers show a large amount of scarring throughout the meander belt, making it impossible to discern the exact trace of the channel. In fact, field surveying indicates that often times the channel traces from both data sets are incorrect. As a result, in areas where there is no clear channel trace, we calculate a local relief across the meander belt as a proxy for the degree of meandering. We find that in channels where it is possible to calculate sinuosity, there are distinct patterns related to local faulting; in those channels in which we cannot calculate sinuosity, meander belt relief patterns indicate increased channel meandering in proximity to the fault zone. The red and green paths correspond to the USGS 10m and LIDAR respectivly. Both were obtained using automated river mmapping.

  10. Technical and economic feasibility of salt-gradient solar ponds at the Truscott Brine Lake of the Red River Chloride Control Project. A report to the House-Senate Committee on Appropriations of the Ninety-Seventh Congress

    SciTech Connect

    Not Available

    1982-09-01

    The Truscott Brine Lake is being constructed to impound highly brackish water from a number of sources which would normally flow into the Wichita River, a tributary of the Red River in Knox County, Texas. A 35.4-km (22-mile) pipeline is being constructed to carry the brines from their primary source to the Truscott Brine Lake site. The reservoir is designed to contain 100 years of brine emissions from three chloride emission areas in the Wichita River Basin. The solar ponds and power generating facilities would be located in the Bluff Creek Arm of Truscott Brine Lake. The Truscott Brine Lake study includes: survey of suitability of Truscott Lake site, review of solar pond technology, preconceptual design of solar salt pond power plant, and economic evaluation.

  11. Deep drilling phase of the Pen Brand Fault Program

    SciTech Connect

    Stieve, A.

    1991-05-15

    This deep drilling activity is one element of the Pen Branch Fault Program at Savannah River Site (SRS). The effort will consist of three tasks: the extension of wells PBF-7 and PBF-8 into crystalline basement, geologic and drilling oversight during drilling operations, and the lithologic description and analysis of the recovered core. The drilling program addresses the association of the Pen Branch fault with order fault systems such as the fault that formed the Bunbarton basin in the Triassic.

  12. Verification of water-quality model to simulate effects of discharging treated wastewater during ice-cover conditions to the Red River of the North at Fargo, North Dakota, and Moorhead, Minnesota

    USGS Publications Warehouse

    Wesolowski, E.A.

    1995-01-01

    The Red River at Fargo Water-Quality (RRatFGO QW) Model, which used the Enhanced Stream Water Quality Model (QUAL2E) computer program, was calibrated and verified for ice-free conditions. The purpose of this study was to verify the model for ice-cover conditions using the same Red River of the North study reach that was used for ice-free conditions. The study reach begins about 0.1 mile downstream of the 12th Avenue North bridge in Fargo, North Dakota, and extends 30.8 miles downstream to a site 0.8 mile upstream of the confluence of the Buffalo River and the Red River of the North. The study reach receives treated wastewater outflow from municipal wastewater-treatment plants at Fargo, North Dakota, and Moorhead, Minnesota, and inflow from the Sheyenne River. For simulations conducted for ice-cover conditions, the RRatFGO QW Model will be referred to as the Red River at Fargo Ice-Cover Water-Quality (RRatFGOIC QW) Model. Streamflow measurements were made at 10 sites during February 21-24, 1995, and water-quality samples were collected and field properties were measured at 12 sites during February 23-24, 1995. Properties and constituents analyzed for include specific conductance, water temperature, dissolved oxygen, 5-day carbonaceous biochemical oxygen demand, total nitrite (reported as nitrogen), total nitrite plus nitrate (reported as nitrogen), total ammonia (reported as nitrogen), total organic nitrogen (reported as nitrogen), total phosphorus (reported as phosphorus), chlorophyll a, and algal biomass. The RRatFGOIC QW Model simulated streamflow, specific conductance, total organic nitrogen, total ammonia, total nitrite, total nitrite plus nitrate, 5-day carbonaceous biochemical oxygen demand, and dissolved oxygen. The model was considered verified for ice-cover conditions for all of the values or concentrations simulated except for the total organic nitrogen concentrations. Based on the results of this study, the QUAL2E Model computer program that was calibrated for ice-free conditions is capable of simulating water quality for both ice-free and ice-cover conditions.

  13. Questa baseline and pre-mining ground-water quality investigation. 12. Geochemical and reactive-transport modeling based on tracer injection-synoptic sampling studies for the Red River, New Mexico, 2001-2002

    USGS Publications Warehouse

    Ball, James W.; Runkel, Robert L.; Nordstrom, D. Kirk

    2005-01-01

    Reactive-transport processes in the Red River, downstream from the town of Red River in north-central New Mexico, were simulated using the OTEQ reactive-transport model. The simulations were calibrated using physical and chemical data from synoptic studies conducted during low-flow conditions in August 2001 and during March/April 2002. Discharge over the 20-km reach from the town of Red River to the USGS streamflow-gaging station near the town of Questa ranged from 395 to 1,180 L/s during the 2001 tracer and from 234 to 421 L/s during the 2002 tracer. The pH of the Red River ranged from 7.4 to 8.5 during the 2001 tracer and from 7.1 to 8.7 during the 2002 tracer, and seep and tributary samples had pH values of 2.8 to 9.0 during the 2001 tracer and 3.8 to 7.2 during the 2002 tracer. Mass-loading calculations allowed identification of several specific locations where elevated concentrations of potential contaminants entered the Red River . These locations, characterized by features on the north side of the Red River that are known to be sources of low-pH water containing elevated metal and sulfate concentrations, are: the initial 2.4 km of the study reach, including Bitter Creek, the stream section from 6.2 to 7.8 km, encompassing La Bobita well and the Hansen debris fan, Sulphur Gulch, at about 10.5 km, the area near Portal Springs, from 12.2 to 12.6 km, and the largest contributors of mass loading, the 13.7 to 13.9 km stream section near Cabin Springs and the 14.7 to 17.5 km stream section from Shaft Spring to Thunder Bridge, Goathill Gulch, and Capulin Canyon. Speciation and saturation index calculations indicated that although solubility limits the concentration of aluminum above pH 5.0, at pH values above 7 and aluminum concentrations below 0.3 mg/L inorganic speciation and mineral solubility controls no longer dominate and aluminum-organic complexing may occur. The August 2001 reactive-transport simulations included dissolved iron(II) oxidation, constrained using measured concentrations of dissolved iron(II) and dissolved iron(total). Both simulations included precipitation of amorphous Al(OH)3 and hydrous ferric oxide as Fe(OH)3, and sorption of copper and zinc to the precipitated hydrous ferric oxide. Simulations revealed that hydrogen, iron, aluminum, copper, and zinc were non-conservative and that mineral precipitation can account for iron and aluminum concentrations. Copper and zinc concentrations can be accounted for by simulating their sorption to hydrous ferric oxide forming in the water column of the Red River , although hydrous manganese oxides also may be important sorption substrates.

  14. Clustering spatio-seasonal hydrogeochemical data using self-organizing maps for groundwater quality assessment in the Red River Delta, Vietnam

    NASA Astrophysics Data System (ADS)

    Nguyen, Thuy Thanh; Kawamura, Akira; Tong, Thanh Ngoc; Nakagawa, Naoko; Amaguchi, Hideo; Gilbuena, Romeo

    2015-03-01

    The Red River Delta (RRD) is the second largest delta in Vietnam, and its local communities depend on groundwater sources for water supply. A clear understanding of the groundwater hydrogeochemical properties, particularly their changes from the dry to rainy seasons and spatial characteristics, is invaluable and indispensable for the management and protection of this important water resource. In this study, self-organizing maps was systematically applied for the first time to investigate the seasonal and spatial hydrogeochemical characteristics of groundwater in the Pleistocene confined aquifer of the RRD. The hydrogeochemical characteristics clustered by SOM were further examined using the Gibbs Diagrams. The groundwater chemistry dataset used in the analysis comprised eight major dissolved ions (i.e., Ca2+, Mg2+, Na+, K+, HCO3-, Cl-, SO42-, and CO32-) and total dissolved solids that were collected from 52 groundwater monitoring wells within the study area during the dry and rainy seasons. Based on the results, the hydrogeochemical groundwater data of the confined aquifer monitoring wells for the delta were classified into 8 clusters, which revealed three basic representative water types: high salinity (2 clusters), low salinity (3 clusters), and freshwater (3 clusters). The high-salinity types were located in the middle-stream and coastal areas of the RRD, while the low-salinity types were observed near the western and northeastern boundaries of the delta. Cluster changes from the dry to rainy seasons were detected in approximately one-third of the observation wells. The increase in groundwater recharge during the rainy season is the main reason for these changes. Based on Gibbs diagrams, the source of soluble ions in the groundwater of the freshwater types was found to be the weathering of rock-forming minerals, while evaporation and marine activities (leaching from salty paleowater and salt water intrusion) were found to be the main factors affecting the chemistry of the groundwater characterized by the low- and high- salinity types, respectively.

  15. The Historical Demography and Genetic Variation of the Endangered Cycas multipinnata (Cycadaceae) in the Red River Region, Examined by Chloroplast DNA Sequences and Microsatellite Markers

    PubMed Central

    Gong, Yi-Qing; Zhan, Qing-Qing; Nguyen, Khang Sinh; Nguyen, Hiep Tien; Wang, Yue-Hua; Gong, Xun

    2015-01-01

    Cycas multipinnata C.J. Chen & S.Y. Yang is a cycad endemic to the Red River drainage region that occurs under evergreen forest on steep limestone slopes in Southwest China and northern Vietnam. It is listed as endangered due to habitat loss and over-collecting for the ornamental plant trade, and only several populations remain. In this study, we assess the genetic variation, population structure, and phylogeography of C. multipinnata populations to help develop strategies for the conservation of the species. 60 individuals from six populations were used for chloroplast DNA (cpDNA) sequencing and 100 individuals from five populations were genotyped using 17 nuclear microsatellites. High genetic differentiation among populations was detected, suggesting that pollen or seed dispersal was restricted within populations. Two main genetic clusters were observed in both the cpDNA and microsatellite loci, corresponding to Yunnan China and northern Vietnam. These clusters indicated low levels of gene flow between the regions since their divergence in the late Pleistocene, which was inferred from both Bayesian and coalescent analysis. In addition, the result of a Bayesian skyline plot based on cpDNA portrayed a long history of constant population size followed by a decline in the last 50,000 years of C. multipinnata that was perhaps affected by the Quaternary glaciations, a finding that was also supported by the Garza-Williamson index calculated from the microsatellite data. The genetic consequences produced by climatic oscillations and anthropogenic disturbances are considered key pressures on C. multipinnata. To establish a conservation management plan, each population of C. multipinnata should be recognized as a Management Unit (MU). In situ and ex situ actions, such as controlling overexploitation and creating a germplasm bank with high genetic diversity, should be urgently implemented to preserve this species. PMID:25689828

  16. The historical demography and genetic variation of the endangered Cycas multipinnata (Cycadaceae) in the red river region, examined by chloroplast DNA sequences and microsatellite markers.

    PubMed

    Gong, Yi-Qing; Zhan, Qing-Qing; Nguyen, Khang Sinh; Nguyen, Hiep Tien; Wang, Yue-Hua; Gong, Xun

    2015-01-01

    Cycas multipinnata C.J. Chen & S.Y. Yang is a cycad endemic to the Red River drainage region that occurs under evergreen forest on steep limestone slopes in Southwest China and northern Vietnam. It is listed as endangered due to habitat loss and over-collecting for the ornamental plant trade, and only several populations remain. In this study, we assess the genetic variation, population structure, and phylogeography of C. multipinnata populations to help develop strategies for the conservation of the species. 60 individuals from six populations were used for chloroplast DNA (cpDNA) sequencing and 100 individuals from five populations were genotyped using 17 nuclear microsatellites. High genetic differentiation among populations was detected, suggesting that pollen or seed dispersal was restricted within populations. Two main genetic clusters were observed in both the cpDNA and microsatellite loci, corresponding to Yunnan China and northern Vietnam. These clusters indicated low levels of gene flow between the regions since their divergence in the late Pleistocene, which was inferred from both Bayesian and coalescent analysis. In addition, the result of a Bayesian skyline plot based on cpDNA portrayed a long history of constant population size followed by a decline in the last 50,000 years of C. multipinnata that was perhaps affected by the Quaternary glaciations, a finding that was also supported by the Garza-Williamson index calculated from the microsatellite data. The genetic consequences produced by climatic oscillations and anthropogenic disturbances are considered key pressures on C. multipinnata. To establish a conservation management plan, each population of C. multipinnata should be recognized as a Management Unit (MU). In situ and ex situ actions, such as controlling overexploitation and creating a germplasm bank with high genetic diversity, should be urgently implemented to preserve this species. PMID:25689828

  17. New tectono-geochronological constraints on timing of shearing along the Ailao Shan-Red River shear zone: Implications for genesis of Ailao Shan gold mineralization

    NASA Astrophysics Data System (ADS)

    Liu, Junlai; Chen, Xiaoyu; Wu, Wenbin; Tang, Yuan; Tran, My-Dung; Nguyen, Quang-Luat; Zhang, Zhaochong; Zhao, Zhidan

    2015-05-01

    Several world class gold deposits are located along the Ailao Shan (ALS) belt in eastern Tibet, China. The genesis of gold mineralization along the belt, however, has been the subject of debates in the last decades, which highlights the importance of dating shearing, magmatism and mineralization along the Ailao Shan-Red River shear zone (ASRR). Through detailed field observations and microscopic analysis, a group of leucocratic intrusions from within and outside the shear zone along the ALS belt are investigated in the present paper. Pre-, syn- and post-shearing intrusions are grouped based on structural and microstructural analysis. LA-ICP-MS and SIMS dating of the intrusions revealed the existence of two age populations, a group of ages older than 30 Ma and the other younger than 28 Ma. The former are distributed both within and outside the shear zone, and the latter, in contrast, occur only within the shear zone. Our new results show that the ductile shearing along the ASRR shear zone initiated since ca. 30 Ma ago. The dating results place major constraints on timing of shearing along the ASRR shear zone and have profound implications on the genesis of gold mineralization along the ALS belt. The present study reveals that ductile shearing along the ASRR shear zone was resulted from extrusion of the Indochina block late during the Indian-Eurasian plate collision. Meanwhile, we conclude that the gold mineralization took place prior to the shearing, but in close relation to an early magmatism (>30 Ma) ascribed to post-collisional extension collapse involving mantle processes, early during the plate collision.

  18. Weather and Management Effects over Nine Years of Net Ecosystem Direct Greenhouse Gas Emissions from a Cropping System in the Red River Valley, Manitoba

    NASA Astrophysics Data System (ADS)

    Tenuta, M.; Amiro, B. D.

    2014-12-01

    Variation in weather and crop management practices strongly determines direct greenhouse gas emissions (CO2 and N2O) from agricultural crop land. Thus a long-term study was established to relate weather and management variations to direct emissions in the Northern Great Plains of Canada. Continuously emission determinations of CO2 and N2O were established at the Trace Gas Manitoba (TGAS-MAN) Long Term Greenhouse Gas Monitoring Site at Glenlea, Manitoba, using the flux gradient micrometeorlogical technique with a tunable diode laser analyzer. The soil is poorly drained clay in the Red River Valley. The field experiment consisted of four 4-hectare plots planted to corn in 2006 and faba bean in 2007. In 2008, grass-alfalfa forage was introduced to two plots (annual - perennial) and grown until 2011 whereas the other two plots (annual) were planted to annual crops: spring wheat, rapeseed, barley and spring wheat in 2008, 2009, 2010 and 2011, respectively. In late September of 2011 the grass-alfalfa forage was killed and in 2012, 2013 and 2014 all four plots were planted with corn, soybean and spring wheat, respectively. Management decisions increased emissions such as fertilizer N addition, and hay, straw and silage crop removal greatly increased emissions while choosing legume grain and perennial crops reduced emissions. Weather variation affecting seasonal and daily soil moisture, length of spring freeze-thaw period, and crop yield served to increase or decrease emissions. The variation in management and weather will be discussed in regards to impact on net emissions over the nine year study and answer if development of greenhouse gas neutral cropping systems is possible.

  19. Activity of the Northern Foothills Thrust Fault: Strain Partitioning Related to the Denali Fault, Central Alaska

    NASA Astrophysics Data System (ADS)

    Hanson, K. L.; Wells, D. L.; Angell, M.

    2002-12-01

    Compression and uplift occurring in the foothills of the Alaska Range north of the Denali fault is attributed to significant strain partitioning that occurs along the central reach of the Denali fault. In the proposed model, oblique slip is transferred from steeply-dipping faults along and adjacent to the Denali fault to the north-vergent Northern Foothills thrust system. This informally named thrust system appears to extend for more than 200 km along the Northern Foothills of the Alaska Range from the Delta River westward to the Kantishna Hills. The inferred geometries suggest that the transfer of strain is accommodated in part by aseismic processes at depths below the seismogenic crust (deeper than ~ 20 km). Relatively uniform uplift occurs between the Denali fault and the Hines Creek fault above the steeper part of the inferred ramp. The ramp extends north to the Northern Foothills, where the thrust is inferred to steepen upward to the edge of the foothills at boundary of the Kuskokwim and Tanana Lowlands. A wedge geometry is suggested by the relationship of an active back thrust (the Healy Creek fault) to the Northern Foothills thrust fault in the area along the Nenana River. In this model, the Healy fault is modeled as a secondary splay of the Healy Creek fault. The Northern Foothills thrust consists of an emergent fault that borders the northernmost outcrops of Nenana Gravel east of the Nenana River. Locally, a secondary splay appears to have developed outboard of the main fault trace. The location and late Pleistocene slip rate for the Northern Foothills thrust fault in the vicinity of the Nenana River is based on review of previous detailed Quaternary geologic mapping and topographic profiles of the glacial outwash terraces along the Nenana River, photogeologic interpretation, and limited field reconnaissance. A long term average vertical slip rate of 0.1 to 0.4 mm/yr is estimated based on the apparent structural relief of the Nenana gravels (deposited between 8.4 to 2.8 Ma). Topographic profiles of the Healy outwash plain surface (~34 to 72 ka) show evidence for deformation across two possible traces of the fault. A vertical slip rate of 0.13 to 0.5 mm/yr is estimated for the southernmost trace of the thrust fault that appears to be associated with post-Healy outwash surface normal faulting in the hanging wall. A vertical slip rate of 0.13 to 0.26 mm/yr is estimated for a possible northern splay.

  20. Automated distribution fault locating system

    SciTech Connect

    Hager, G.E.; Medicine Bear, R.N.; Baum, A.S.

    1996-05-01

    An automated fault locating system (FLS) was designed and implemented for the Colorado River Agency (CRA) 12.5/7.2-kV distribution system. This FLS was integrated into the supervisory control and data acquisition (SCADA) system which was installed at a hydropower plant. This FLS offers several benefits to the CRA distribution system. These benefits include reduced outage time, help in locating momentary faults, enhanced safety to the line crews, provide notification of an outage without receiving calls from the consumer, and decreased overtime.

  1. Changes in streamflow and summary of major-ion chemistry and loads in the North Fork Red River basin upstream from Lake Altus, northwestern Texas and western Oklahoma, 1945-1999

    USGS Publications Warehouse

    Smith, S. Jerrod; Wahl, Kenneth L.

    2003-01-01

    Upstream from Lake Altus, the North Fork Red River drains an area of 2,515 square miles. The quantity and quality of surface water are major concerns at Lake Altus, and water-resource managers and consumers need historical information to make informed decisions about future development. The Lugert-Altus Irrigation District relies on withdrawals from the lake to sustain nearly 46,000 acres of agricultural land. Kendall's tau tests of precipitation data indicated no statistically significant trend over the entire 100 years of available record. However, a significant increase in precipitation occurred in the last 51 years. Four streamflow-gaging stations with more than 10 years of record were maintained in the basin. These stations recorded no significant trends in annual streamflow volume. Two stations, however, had significant increasing trends in the base-flow index, and three had significant decreasing trends in annual peak flows. Major-ion chemistry in the North Fork Red River is closely related to the chemical composition of the underlying bedrock. Two main lithologies are represented in the basin upstream from Lake Altus. In the upper reaches, young and poorly consolidated sediments include a range of sizes from coarse gravel to silt and clay. Nearsurface horizons commonly are cemented as calcium carbonate caliche. Finer-grained gypsiferous sandstones and shales dominate the lower reaches of the basin. A distinct increase in dissolved solids, specifically sodium, chloride, calcium, and sulfate, occurs as the river flows over rocks that contain substantial quantities of gypsum, anhydrite, and dolomite. These natural salts are the major dissolved constituents in the North Fork Red River.

  2. Seismic and gravity investigations of the shallow (upper 1 km) hanging wall of the Alpine Fault in the vicinity of the Whataroa River, New Zealand

    NASA Astrophysics Data System (ADS)

    Kovacs, A.; Gorman, A. R.; Lay, V.; Buske, S.

    2013-12-01

    Paleoseismic evidence from the vicinity of the plate-bounding Alpine Fault on New Zealand's South Island suggests that earthquakes of magnitude 7.9 occur every 200-400 years, with the last earthquake occurring in AD 1717. No human observations of this event are recorded. Therefore, the Deep Fault Drilling Project 2 (DFDP-2) drill hole, which is planned for 2014 on the hanging wall of the Alpine Fault in the Whataroa Valley, provides a critical opportunity to study the behavior of this transpressive plate boundary late in its seismogenic cycle. New seismic and gravity data collected since 2011 have been analyzed to assist with the positioning of the drill hole in this glacial valley that provides rare low-elevation access to the hanging wall of the Alpine Fault. The WhataDUSIE controlled-source seismic project, led by researchers from the University of Otago (New Zealand), TU Bergakademie Freiberg (Germany) and the University of Alberta (Canada), provided relatively high-resolution coverage (4-8 m geophone spacing, 25-100 m shot spacing) along a 5-km-long profile across the Alpine Fault in the Whataroa Valley. This work has been supplemented by focused hammer-seismic studies and gravity data collection in the valley. The former targets surface layer properties, whereas the latter targets the depth to the base of the glacially carved paleovalley. In positioning DFDP-2, an understanding of the nature of overburden and valley-fill sediments is critical for drilling design. A velocity model has been developed for the valley based on refraction analysis of the WhataDUSIE and hammer-seismic data combined with a ray-theoretical travel-time tomography (RAYINVR) image of the shallow (uppermost 1 km or so) part of the hanging wall of the Alpine Fault. The model shows that the glacial valley, which presumably was last scoured by ice at the Last Glacial Maximum, has been filled with 200-350 m of post-glacial sediments and outwash gravels. The hanging-wall rocks into which the valley was cut are presumed to be mylonitized Alpine Schist. Considering uplift rates of 6-10 mm/a on the hanging wall of the fault and a glacial withdrawal date of 10,000 years before present (i.e., 60-100 m of uplift since the ice vacated the valley), the floor of the valley would have been as deep as about 350 m below sea level at the time that the ice withdrew (given the current elevation of ~100 m on the valley floor). Basal sediments in the valley could therefore be either marine (if the valley was open to the ocean) or lacustrine (if the valley was isolated from the open ocean by elevated footwall rocks along the west coast of the South Island). Once the original water body in the valley was filled, sediments would accumulate as outwash gravels above sea level.

  3. Neotectonics of Panama. I. Major fault systems

    SciTech Connect

    Corrigan, J.; Mann, P.

    1985-01-01

    The direction and rate of relative plate motion across the Caribbean-Nazca boundary in Panama is poorly known. This lack of understanding can be attributed to diffuse seismicity; lack of well constrained focal mechanisms from critical areas; and dense tropical vegetation. In order to better understand the relation of plate motions to major fault systems in Panama, the authors have integrated geologic, remote sensing, earthquake and UTIG marine seismic reflection data. Three areas of recent faulting can be distinguished in Panama and its shelf areas; ZONE 1 of eastern Panama consists of a 70 km wide zone of 3 discrete left-lateral strike-slip faults (Sanson Hills, Jaque River, Sambu) which strike N40W and can be traced as continuous features for distances of 100-150 km; ZONE 2 in central Panama consists of a diffuse zone of discontinuous normal(.) faults which range in strike from N40E, N70E; ZONE 3 in western Panama consists of a 60 km wide zone of 2 discrete, left-lateral(.) strike-slip faults which strike N60W and can be traced as continuous features for distances of 150 km; ZONE 3 faults appear to be continuous with faults bounding the forearc Teraba Trough of Costa Rica. The relation of faults of ZONE 3 to faults of ZONE 2 and a major fault bounding the southern Panama shelf is unclear.

  4. Amu Darya River

    Atmospheric Science Data Center

    2013-04-16

    article title:  Amu Darya River     View Larger Image This false-color image of the Amu Darya River was acquired by the Multi-angle Imaging SpectroRadiometer (MISR) in late ... highly vegetated areas to appear red. The Amu Darya river forms a wide delta in the western deserts of Uzbekistan and northeastern ...

  5. Species delimitation, genetic diversity and population historical dynamics of Cycas diannanensis (Cycadaceae) occurring sympatrically in the Red River region of China

    PubMed Central

    Liu, Jian; Zhou, Wei; Gong, Xun

    2015-01-01

    Delimitating species boundaries could be of critical importance when evaluating the species' evolving process and providing guidelines for conservation genetics. Here, species delimitation was carried out on three endemic and endangered Cycas species with resembling morphology and overlapped distribution range along the Red River (Yuanjiang) in China: Cycas diananensis Z. T. Guan et G. D. Tao, Cycas parvula S. L. Yang and Cycas multiovula D. Y. Wang. A total of 137 individuals from 15 populations were genotyped by using three chloroplastic (psbA-trnH, atpI-atpH, and trnL-rps4) and two single copy nuclear (RPB1 and SmHP) DNA sequences. Basing on the carefully morphological comparison and cladistic haplotype aggregation (CHA) analysis, we propose all the populations as one species, with the rest two incorporated into C. diannanensis. Genetic diversity and structure analysis of the conflated C. diannanensis revealed this species possessed a relative lower genetic diversity than estimates of other Cycas species. The higher genetic diversity among populations and relative lower genetic diversity within populations, as well as obvious genetic differentiation among populations inferred from chloroplastic DNA (cpDNA) suggested a recent genetic loss within this protected species. Additionally, a clear genetic structure of C. diannanensis corresponding with geography was detected based on cpDNA, dividing its population ranges into “Yuanjiang-Nanhun” basin and “Ejia-Jiepai” basin groups. Demographical history analyses based on combined cpDNA and one nuclear DNA (nDNA) SmHP both showed the population size of C. diannanensis began to decrease in Quaternary glaciation with no subsequent expansion, while another nDNA RPB1 revealed a more recent sudden expansion after long-term population size contraction, suggesting its probable bottleneck events in history. Our findings offer grounded views for clarifying species boundaries of C. diannanensis when determining the conservation objectives. For operational guidelines, the downstream populations which occupy high and peculiar haplotypes should be given prior in-situ conservation. In addition, ex-situ conservation and reintroduction measures for decades of generations are supplemented for improving the population size and genetic diversity of the endemic and endangered species. PMID:26442013

  6. Greenhouse Gas Emissions Increase Following the Termination of a Perennial Legume Phase of an Annual Crop Rotation within the Red River Valley, Manitoba

    NASA Astrophysics Data System (ADS)

    Hanis, K. L.; Tenuta, M.; Amiro, B. D.; Glenn, A. J.; Maas, S.; Gervais, M.

    2013-12-01

    Perennial legume forages may have the potential to increase soil carbon sequestration and decrease nitrous oxide (N2O) emissions to the atmosphere when introduced into annual cropping systems. However, little is known about what short-term effect the return to annual cropping following termination of perennial legume forage would have on carbon dioxide (CO2) and N2O emissions. Furthermore, there are few quantitative measurements about this impact on the Canadian Prairies. A long-term field experiment to continuously measure CO2 and N2O fluxes was established at the Trace Gas Manitoba (TGAS-MAN) Long Term Greenhouse Gas Monitoring Site at Glenlea, Manitoba using the flux gradient micrometeorlogical technique with a tunable diode laser analyzer. The soil is poorly drained clay in the Red River Valley. The field experiment consisted of four 4-hectare plots planted to corn in 2006 and faba bean in 2007. In 2008, grass-alfalfa forage was introduced to two plots (annual - perennial) and grown until 2011 whereas the other two plots (annual) were planted to annual crops: spring wheat, rapeseed, barley and spring wheat in 2008, 2009, 2010 and 2011, respectively. In late September of 2011 the grass-alfalfa forage was killed and in 2012 all four plots were planted with corn. Termination of the grass-alfalfa forage resulted in greater fall CO2 emissions in 2011, greater spring melt CO2 emissions and net annual N2O emissions in 2012 from the annual-perennial plots when compared to the annual plots. Over seven crop years (2006-2012), the annual - perennial system increased carbon uptake by 3.4 Mg C ha-1 and reduced N2O emissions by 3.0 Mg CO2-eq ha-1 compared to the annual system. However after accounting for harvest removals both the annual and annual-perennial systems were net carbon sources of 5.7 and 2.5 Mg C ha-1 and net GHG sources of 38 and 24 Mg CO2-eq ha-1 respectively. We are currently following the long-term impacts of inclusion of perennial forages in an annual cropping system.

  7. Possible Extent and Depth of Salt Contamination in Ground Water Using Geophysical Techniques, Red River Aluminum Site, Stamps, Arkansas, April 2003

    USGS Publications Warehouse

    Stanton, Gregory P.; Kress, Wade; Hobza, Christopher M.; Czarnecki, John B.

    2003-01-01

    A surface-geophysical investigation of the Red River Aluminum site at Stamps, Arkansas, was conducted in cooperation with the Arkansas Department of Environmental Quality to determine the possible extent and depth of saltwater contamination. Water-level measurements indicate the distance to water level below land surface ranges from about 1.2 to 3.9 feet (0.37 to 1.19 meters) in shallow monitor wells and about 10.5 to 17.1 feet (3.20 to 5.21 meters) in deeper monitoring wells. The two-dimensional, direct-current resistivity method identified resistivities less than 5 ohm-meters which indicated possible areas of salt contamination occurring in near-surface or deep subsurface ground water along four resistivity lines within the site. One line located east of the site yielded data that demonstrated no effect of salt contamination. Sections from two of the five data sets were modeled. The input model grids were created on the basis of the known geology and the results and interpretations of borehole geophysical data. The clay-rich Cook Mountain Formation is modeled as 25 ohm-meters and extends from 21 meters (68.9 feet) below land surface to the bottom of the model (about 52 meters (170.6 feet)). The models were used to refine interpretation of the resistivity data and to determine extent of saltwater contamination and depth to the Cook Mountain Formation. Data from the resistivity lines indicate both near-surface and subsurface saltwater contamination. The near-surface contamination appears as low resistivity (less than 5 ohm-meters) on four of the five resistivity lines, extending up to 775 meters (2,542.8 feet) horizontally in a line that traverses the entire site south to north. Model resistivity data indicate that the total depth of saltwater contamination is about 18 meters (59 feet) below land surface. Data from four resistivity lines identified areas containing low resistivity anomalies interpreted as possible salt contamination. A fifth line located just east of the site showed no saltwater contamination.

  8. Risk factors of highly pathogenic avian influenza H5N1 occurrence at the village and farm levels in the Red River Delta Region in Vietnam.

    PubMed

    Desvaux, S; Grosbois, V; Pham, T T H; Fenwick, S; Tollis, S; Pham, N H; Tran, A; Roger, F

    2011-12-01

    A case-control study at both village and farm levels was designed to investigate risk factors for highly pathogenic avian influenza H5N1 during the 2007 outbreaks in one province of Northern Vietnam. Data related to human and natural environments, and poultry production systems were collected for 19 case and 38 unmatched control villages and 19 pairs of matched farms. Our results confirmed the role of poultry movements and trading activities. In particular, our models found that higher number of broiler flocks in the village increased the risk (OR = 1.49, 95% CI: 1.12-1.96), as well as the village having at least one poultry trader (OR = 11.53, 95% CI: 1.34-98.86). To a lesser extent, in one of our two models, we also identified that increased density of ponds and streams, commonly used for waterfowl production, and greater number of duck flocks in the village also increased the risk. The higher percentage of households keeping poultry, as an indicator of households keeping backyard poultry in our study population, was a protective factor (OR = 0.95, 95% CI: 0.91-0.98). At the farm level, three risk factors at the 5% level of type I error were identified by univariate analysis: a greater total number of birds (P = 0.006), increase in the number of flocks having access to water (P = 0.027) and a greater number of broiler flocks in the farm (P = 0.049). Effect of vaccination implementation (date and doses) was difficult to investigate because of a poor recording system. Some protective or risk factors with limited effect may not have been identified owing to our limited sample size. Nevertheless, our results provide a better understanding of local transmission mechanisms of HPAI H5N1 in one province of the Red River Delta region in Vietnam and highlight the need to reduce at-risk trading and production practices. PMID:21545692

  9. Continuous Water-Quality Monitoring and Regression Analysis to Estimate Constituent Concentrations and Loads in the Red River of the North, Fargo, North Dakota, 2003-05

    USGS Publications Warehouse

    Ryberg, Karen R.

    2006-01-01

    This report presents the results of a study by the U.S. Geological Survey, done in cooperation with the Bureau of Reclamation, U.S. Department of the Interior, to estimate water-quality constituent concentrations in the Red River of the North at Fargo, North Dakota. Regression analysis of water-quality data collected in 2003-05 was used to estimate concentrations and loads for alkalinity, dissolved solids, sulfate, chloride, total nitrite plus nitrate, total nitrogen, total phosphorus, and suspended sediment. The explanatory variables examined for regression relation were continuously monitored physical properties of water-streamflow, specific conductance, pH, water temperature, turbidity, and dissolved oxygen. For the conditions observed in 2003-05, streamflow was a significant explanatory variable for all estimated constituents except dissolved solids. pH, water temperature, and dissolved oxygen were not statistically significant explanatory variables for any of the constituents in this study. Specific conductance was a significant explanatory variable for alkalinity, dissolved solids, sulfate, and chloride. Turbidity was a significant explanatory variable for total phosphorus and suspended sediment. For the nutrients, total nitrite plus nitrate, total nitrogen, and total phosphorus, cosine and sine functions of time also were used to explain the seasonality in constituent concentrations. The regression equations were evaluated using common measures of variability, including R2, or the proportion of variability in the estimated constituent explained by the regression equation. R2 values ranged from 0.703 for total nitrogen concentration to 0.990 for dissolved-solids concentration. The regression equations also were evaluated by calculating the median relative percentage difference (RPD) between measured constituent concentration and the constituent concentration estimated by the regression equations. Median RPDs ranged from 1.1 for dissolved solids to 35.2 for total nitrite plus nitrate. Regression equations also were used to estimate daily constituent loads. Load estimates can be used by water-quality managers for comparison of current water-quality conditions to water-quality standards expressed as total maximum daily loads (TMDLs). TMDLs are a measure of the maximum amount of chemical constituents that a water body can receive and still meet established water-quality standards. The peak loads generally occurred in June and July when streamflow also peaked.

  10. Calibration of a Water-Quality Model for Low-Flow Conditions on the Red River of the North at Fargo, North Dakota, and Moorhead, Minnesota, 2003

    USGS Publications Warehouse

    Lundgren, Robert F.; Nustad, Rochelle A.

    2008-01-01

    A time-of-travel and reaeration-rate study was conducted by the U.S. Geological Survey, in cooperation with the North Dakota Department of Health, the Minnesota Pollution Control Agency, and the cities of Fargo, North Dakota, and Moorhead, Minnesota, to provide information to calibrate a water-quality model for streamflows of less than 150 cubic feet per second. Data collected from September 24 through 27, 2003, were used to develop and calibrate the U.S. Environmental Protection Agency Water Quality Analysis Simulation Program model (hereinafter referred to as the Fargo WASP water-quality model) for a 19.2-mile reach of the Red River of the North. The Fargo WASP water-quality model was calibrated for the transport of dye by fitting simulated time-concentration dye curves to measured time-concentration dye curves. Simulated peak concentrations were within 10 percent of measured concentrations. Simulated traveltimes of the dye cloud centroid were within 7 percent of measured traveltimes. The variances of the simulated dye concentrations were similar to the variances of the measured dye concentrations, indicating dispersion was reproduced reasonably well. Average simulated dissolved-oxygen concentrations were within 6 percent of average measured concentrations. Average simulated ammonia concentrations were within the range of measured concentrations. Simulated dissolved-oxygen and ammonia concentrations were affected by the specification of a single nitrification rate in the Fargo WASP water-quality model. Data sets from August 1989 and August 1990 were used to test traveltime and simulation of dissolved oxygen and ammonia. For streamflows that ranged from 60 to 407 cubic feet per second, simulated traveltimes were within 7 percent of measured traveltimes. Measured dissolved-oxygen concentrations were underpredicted by less than 15 percent for both data sets. Results for ammonia were poor; measured ammonia concentrations were underpredicted by as much as 70 percent for both data sets. Overall, application of the Fargo WASP water-quality model to the 1989 and 1990 data sets resulted in poor agreement between measured and simulated concentrations. This likely is a result of changes in the waste-load composition for the Fargo and Moorhead wastewater-treatment plants as a result of improvements to the wastewater-treatment plants since 1990. The change in waste-load composition probably resulted in a change in decay rates and in dissolved oxygen no longer being substantially depressed downstream from the Moorhead and Fargo wastewater-treatment plants. The Fargo WASP water-quality model is valid for the current (2008) treatment processes at the wastewater-treatment plants.

  11. 33 CFR 165.T08-0080 - Safety Zone; Cincinnati Reds Fireworks Displays Ohio River, Mile 470.1-470.4, Cincinnati, OH.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Safety Zone; Cincinnati Reds... Limited Access Areas Eighth Coast Guard District § 165.T08-0080 Safety Zone; Cincinnati Reds Fireworks... 2, 9 & 23; June 6 & 20; July 4, 11 & 25; August 8 & 22; September 5 & 26. Should the Cincinnati...

  12. Quaternary faults of west Texas

    SciTech Connect

    Collins, E.W.; Raney, J.A. . Bureau of Economic Geology)

    1993-04-01

    North- and northwest-striking intermontane basins and associated normal faults in West Texas and adjacent Chihuahua, Mexico, formed in response to Basin and Range tectonism that began about 24 Ma ago. Data on the precise ages of faulted and unfaulted Quaternary deposits are sparse. However, age estimates made on the basis of field stratigraphic relationships and the degree of calcic soil development have helped determine that many of the faults that bound the basin margins ruptured since the middle Pleistocene and that some faults probably ruptured during the Holocene. Average recurrence intervals between surface ruptures since the middle Pleistocene appear to be relatively long, about 10,000 to 100,000 yr. Maximum throw during single rupture events have been between 1 and 3 m. Historic seismicity in West Texas is low compared to seismicity in many parts of the Basin and Range province. The largest historic earthquake, the 1931 Valentine earthquake in Ryan Flat/Lobo Valley, had a magnitude of 6.4 and no reported surface rupture. The most active Quaternary faults occur within the 120-km-long Hueco Bolson, the 70-km-long Red Light Bolson, and the > 200-km-long Salt Basins/Wild Horse Flat/Lobo Valley/Ryan Flat.

  13. Influence of fault trend, fault bends, and fault convergence on shallow structure, geomorphology, and hazards, Hosgri strike-slip fault, offshore central California

    NASA Astrophysics Data System (ADS)

    Johnson, S. Y.; Watt, J. T.; Hartwell, S. R.

    2012-12-01

    We mapped a ~94-km-long portion of the right-lateral Hosgri Fault Zone from Point Sal to Piedras Blancas in offshore central California using high-resolution seismic reflection profiles, marine magnetic data, and multibeam bathymetry. The database includes 121 seismic profiles across the fault zone and is perhaps the most comprehensive reported survey of the shallow structure of an active strike-slip fault. These data document the location, length, and near-surface continuity of multiple fault strands, highlight fault-zone heterogeneity, and demonstrate the importance of fault trend, fault bends, and fault convergences in the development of shallow structure and tectonic geomorphology. The Hosgri Fault Zone is continuous through the study area passing through a broad arc in which fault trend changes from about 338° to 328° from south to north. The southern ~40 km of the fault zone in this area is more extensional, resulting in accommodation space that is filled by deltaic sediments of the Santa Maria River. The central ~24 km of the fault zone is characterized by oblique convergence of the Hosgri Fault Zone with the more northwest-trending Los Osos and Shoreline Faults. Convergence between these faults has resulted in the formation of local restraining and releasing fault bends, transpressive uplifts, and transtensional basins of varying size and morphology. We present a hypothesis that links development of a paired fault bend to indenting and bulging of the Hosgri Fault by a strong crustal block translated to the northwest along the Shoreline Fault. Two diverging Hosgri Fault strands bounding a central uplifted block characterize the northern ~30 km of the Hosgri Fault in this area. The eastern Hosgri strand passes through releasing and restraining bends; the releasing bend is the primary control on development of an elongate, asymmetric, "Lazy Z" sedimentary basin. The western strand of the Hosgri Fault Zone passes through a significant restraining bend and dies out northward where we propose that its slip transfers to active structures in the Piedras Blancas fold belt. Given the continuity of the Hosgri Fault Zone through our study area, earthquake hazard assessments should incorporate a minimum rupture length of 110 km. Our data do not constrain lateral slip rates on the Hosgri, which probably vary along the fault (both to the north and south) as different structures converge and diverge but are likely in the geodetically estimated range of 2 to 4 mm/yr. More focused mapping of lowstand geomorphic features (e.g., channels, paleoshorelines) has the potential to provide better constraints. The post-Last-Glacial Maximum unconformity is an important surface for constraining vertical deformation, yielding local fault offset rates that may be as high as 1.4 mm/yr and off-fault deformation rates as high as 0.5 mm/yr. These vertical rates are short-term and not sustainable over longer geologic time, emphasizing the complex evolution and dynamics of strike-slip zones.

  14. Geometry of miocene extensional deformation, lower Colorado River Region, Southeastern California and Southwestern Arizona: Evidence for the presence of a regional low-angle normal fault

    NASA Astrophysics Data System (ADS)

    Tosdal, R. M.; Sherrod, D. R.

    The geometry of Miocene extensional deformation, which changes along a 120 km-long, northeast-trending transect from the southestern Chocolate Mountains, southeastern California, to the Trigo and southern Dome Rock Mountains, southwestern Arizona is discussed. Based upon regional differences in the structural response to extension and estimated extensional strain, the transet can be divided into three northwesterly-trending structural domains. From southwest to northeast, these domains are: (1) southestern Chocolate-southernmost Trigo Mountains; (2) central to northern Trigo Mountains; and (3) Trigo Peaks-southern Dome Rock Mountains. All structures formed during the deformation are brittle in style; fault rocks are composed of gouge, cohesive gouge, and local microbreccia. In each structural domain, exposed lithologic units are composed of Mesozoic crystalline rocks unconformably overlain by Oligocene to Early Miocene volcanic and minor interbedded sedimentary rocks. Breccia, conglomerate, and sandstone deposited synchronously with regional extension locally overlie the volcanic rocks. Extensional deformation largely postdated the main phase of volcanic activity, but rare rhyolitic tuff and flows interbedded with the syndeformational clastic rocks suggest that deformation began during the waning stages of valcanism. K-Ar isotopic ages indicate that deformation occurred in Miocene time, between about 22 and m.y. ago.

  15. Alteration Map Showing Major Faults and Veins and Associated Water-Quality Signatures of the Animas River Watershed Headwaters Near Silverton, Southwest Colorado

    USGS Publications Warehouse

    Bove, Dana J.; Yager, Douglas B.; Mast, M. Alisa; Dalton, J. Brad

    2007-01-01

    This map was produced to provide hard-copy and digital data for alteration assemblages in the historical mining area centered on the Tertiary San Juan and Silverton calderas. The data have direct application to geoenvironmental and mineral exploration objectives. This dataset represents alteration mapping for the upper Animas River watershed near Silverton, Colorado. The map is based on detailed 1:12,000-scale field mapping, X-ray diffraction (XRD) analysis, mineral mapping by remote sensing (AVIRIS) data, and 1:24,000-scale aerial photographic interpretation. Geologic structures were compiled and generalized from multiple published and unpublished sources (Burbank and Luedke, 1964; Steven and others, 1974; Luedke and Burbank 1975a, b; Lipman, 1976; Luedke and Burbank, 1987; Luedke, 1996) (see Index Map). Unpublished mapping of the Ironton quadrangle by D.J. Bove and J.P. Kurtz in 1997-1999 was included.

  16. Birthmarks - red

    MedlinePlus

    Red birthmarks are skin markings created by blood vessels close to the skin surface. They develop before ... There are two main categories of birthmarks: Red birthmarks are made ... vascular birthmarks. Pigmented birthmarks are areas in which ...

  17. Eye redness

    MedlinePlus

    Bloodshot eyes; Red eyes; Scleral infection; Conjunctival infection ... There are many causes of a red eye or eyes. Some are medical emergencies and some are a cause for concern, but not an emergency. Others are nothing to worry about. ...

  18. Minerals Anomalies and Their Significances in Fault Rocks along the Front Longmenshan Fault

    NASA Astrophysics Data System (ADS)

    Si, J.; Li, H.; Song, S.; Kuo, L.; Pei, J.; Chen, P.; Hsiao, H.; Wang, H.

    2012-12-01

    Anxian-Guanxian fault is the front fault of the Longmenshan fault system. In the Wenchuan earthquake (Ms8.0) of 12 May 2008, the surface rupture zone developed along the Anxian-Guanxian fault was also named as Hanwang rupture zone, which was approximately pure thrust, about 80km long accompanied with the vertical displacement of 0.5~4m averaged about 2m, and the maximum 4.2m occurred in the fifth villager group of Shaba village belonging to the Jiulong Town of Mianzhu City. We made several trenches cutting through the Anxian-Guanxian rupture zone. In the trenches near the Qingquan village of Jiulong town, three different colored strata including black, gray green and red layers developed from west to east. The black segment is carbonaceous mudstone and fault gouge, the gray green part is fault gouge, cataclasite and siltstone, and the purple red section is mainly mudstone with a few thin gouge layers at the top. Two continuous U-channel samples collected from the trench have been prepared for the synchrotron X-ray diffraction measurements. Viewing from the data, clay minerals including illite, mica, kaolinite and chlorite are more abundant in fine and black gouge than the coarse rocks and purple red mudstone. Moreover, there are significant graphite occur at and near the slip plane. Considering the low friction coefficient and the distinct different features different from the Yingxiu-Beichuan fault, the carbon matter might have acted as lubrication and played certain significant role in the faulting process of the slow angle Anxian-Guanxian fault.

  19. 33 CFR 125.06 - Western rivers.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Western rivers. 125.06 Section... VESSELS § 125.06 Western rivers. The term western rivers as used in the regulations in this subchapter shall include only the Red River of the North, the Mississippi River and its tributaries above the...

  20. 33 CFR 125.06 - Western rivers.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Western rivers. 125.06 Section... VESSELS § 125.06 Western rivers. The term western rivers as used in the regulations in this subchapter shall include only the Red River of the North, the Mississippi River and its tributaries above the...

  1. 33 CFR 125.06 - Western rivers.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Western rivers. 125.06 Section... VESSELS § 125.06 Western rivers. The term western rivers as used in the regulations in this subchapter shall include only the Red River of the North, the Mississippi River and its tributaries above the...

  2. 33 CFR 125.06 - Western rivers.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Western rivers. 125.06 Section... VESSELS § 125.06 Western rivers. The term western rivers as used in the regulations in this subchapter shall include only the Red River of the North, the Mississippi River and its tributaries above the...

  3. Red Sea

    Atmospheric Science Data Center

    2013-04-16

    article title:  The Red Sea     View Larger Image ... Multi-angle Imaging SpectroRadiometer (MISR) image of the Red Sea was acquired on August 13, 2000. Located between the East African coast and the Saudi Arabian peninsula, the Red Sea got its name because the blooms of a type of algae,  Trichodesmium ...

  4. Red clover

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Red clover (Trifolium pratense L.) is an important forage legume grown on approximately 4 million hectares worldwide. An estimated 2.8 million kg of red clover seed per year was produced worldwide in 2005-2007. This amount of seed would be enough to maintain approximately 4 million hectares of red...

  5. Fault slip distribution and fault roughness

    NASA Astrophysics Data System (ADS)

    Candela, Thibault; Renard, François; Schmittbuhl, Jean; Bouchon, Michel; Brodsky, Emily E.

    2011-11-01

    We present analysis of the spatial correlations of seismological slip maps and fault topography roughness, illuminating their identical self-affine exponent. Though the complexity of the coseismic spatial slip distribution can be intuitively associated with geometrical or stress heterogeneities along the fault surface, this has never been demonstrated. Based on new measurements of fault surface topography and on statistical analyses of kinematic inversions of slip maps, we propose a model, which quantitatively characterizes the link between slip distribution and fault surface roughness. Our approach can be divided into two complementary steps: (i) Using a numerical computation, we estimate the influence of fault roughness on the frictional strength (pre-stress). We model a fault as a rough interface where elastic asperities are squeezed. The Hurst exponent ?, characterizing the self-affinity of the frictional strength field, approaches ?, where ? is the roughness exponent of the fault surface in the direction of slip. (ii) Using a quasi-static model of fault propagation, which includes the effect of long-range elastic interactions and spatial correlations in the frictional strength, the spatial slip correlation is observed to scale as ?, where ? represents the Hurst exponent of the slip distribution. Under the assumption that the origin of the spatial fluctuations in frictional strength along faults is the elastic squeeze of fault asperities, we show that self-affine geometrical properties of fault surface roughness control slip correlations and that ?. Given that ? for a wide range of faults (various accumulated displacement, host rock and slip movement), we predict that ?. Even if our quasi-static fault model is more relevant for creeping faults, the spatial slip correlations observed are consistent with those of seismological slip maps. A consequence is that the self-affinity property of slip roughness may be explained by fault geometry without considering dynamical effects produced during an earthquake.

  6. 1. CONTEXTUAL VIEW OF THE RED BRIDGE LOOKING NORTH FROM ...

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

    1. CONTEXTUAL VIEW OF THE RED BRIDGE LOOKING NORTH FROM FUEL HOLLOW ROAD. - Red Bridge, Spanning Yellow river at abandoned county road, 7.3 miles northeast of Postville, Postville, Allamakee County, IA

  7. The SCEC 3D Community Fault Model (CFM-v5): An updated and expanded fault set of oblique crustal deformation and complex fault interaction for southern California

    NASA Astrophysics Data System (ADS)

    Nicholson, C.; Plesch, A.; Sorlien, C. C.; Shaw, J. H.; Hauksson, E.

    2014-12-01

    Southern California represents an ideal natural laboratory to investigate oblique deformation in 3D owing to its comprehensive datasets, complex tectonic history, evolving components of oblique slip, and continued crustal rotations about horizontal and vertical axes. As the SCEC Community Fault Model (CFM) aims to accurately reflect this 3D deformation, we present the results of an extensive update to the model by using primarily detailed fault trace, seismic reflection, relocated hypocenter and focal mechanism nodal plane data to generate improved, more realistic digital 3D fault surfaces. The results document a wide variety of oblique strain accommodation, including various aspects of strain partitioning and fault-related folding, sets of both high-angle and low-angle faults that mutually interact, significant non-planar, multi-stranded faults with variable dip along strike and with depth, and active mid-crustal detachments. In places, closely-spaced fault strands or fault systems can remain surprisingly subparallel to seismogenic depths, while in other areas, major strike-slip to oblique-slip faults can merge, such as the S-dipping Arroyo Parida-Mission Ridge and Santa Ynez faults with the N-dipping North Channel-Pitas Point-Red Mountain fault system, or diverge with depth. Examples of the latter include the steep-to-west-dipping Laguna Salada-Indiviso faults with the steep-to-east-dipping Sierra Cucapah faults, and the steep southern San Andreas fault with the adjacent NE-dipping Mecca Hills-Hidden Springs fault system. In addition, overprinting by steep predominantly strike-slip faulting can segment which parts of intersecting inherited low-angle faults are reactivated, or result in mutual cross-cutting relationships. The updated CFM 3D fault surfaces thus help characterize a more complex pattern of fault interactions at depth between various fault sets and linked fault systems, and a more complex fault geometry than typically inferred or expected from projecting near-surface data down-dip, or modeled from surface strain and potential field data alone.

  8. Neotectonic characteristics of Liuchia fault, southwestern Taiwan, from the analysis of fluvial channel morphology

    NASA Astrophysics Data System (ADS)

    Du, Kuan-Ying; Shyu, J. Bruce H.

    2013-04-01

    The Liuchia fault in southwestern Taiwan has been considered as one of major active faults in the active Taiwan orogen. It is identified by its clear geomorphic features, and forms a major geologic boundary of Taiwan's Western Foothills. In the twentieth century, several large earthquakes occurred in southwestern Taiwan and caused significant damages. However, there is no unanimous historical evidence for the activity on the Liuchia fault. Therefore, the Liuchia fault poses large hazard potentials for this populous area. Several previous studies have shown that fluvial channel morphology, such as channel slope and width, is strongly influenced by tectonic activities. As river channels reach steady state, the rock uplift would be balanced by the incision of river channels. Base on these hypotheses, it has been shown previously that the analysis of river channel morphology can successfully estimate the activity of potentially active faults in central Taiwan. As a result, we attempted to obtain information of recent activity of the Liuchia fault by analyzing the channel morphology of the Erchung River, which flows across the fault. We also attempted to calculate the actual river incision rates from the age of river terraces along the river. Such information would enable us to construct the subsurface geometry of this important active structure. We have obtained a detailed river long profile of the Erchung River from surveys using RTK-GPS, and the channel width profile from actual field measurements using a Laser Rangefinder. The fluvial channel morphology of the Erchung River appears to have been affected by active folding in the hanging-wall block of the Liuchia fault. Such active deformation pattern is also evident from river incision rate patterns, calculated from the ages and elevations of river terraces along the channel. We have also measured bedrock attitudes across the Liuchia fault and into its hanging-wall block. Combing these different datasets, we are able to construct a realistic model of the subsurface geometry of the Liuchia fault in southwestern Taiwan.

  9. Fault damage zones

    NASA Astrophysics Data System (ADS)

    Kim, Young-Seog; Peacock, David C. P.; Sanderson, David J.

    2004-03-01

    Damage zones show very similar geometries across a wide range of scales and fault types, including strike-slip, normal and thrust faults. We use a geometric classification of damage zones into tip-, wall-, and linking-damage zones, based on their location around faults. These classes can be sub-divided in terms of fault and fracture patterns within the damage zone. A variety of damage zone structures can occur at mode II tips of strike-slip faults, including wing cracks, horsetail fractures, antithetic faults, and synthetic branch faults. Wall damage zones result from the propagation of mode II and mode III fault tips through a rock, or from damage associated with the increase in slip on a fault. Wall damage zone structures include extension fractures, antithetic faults, synthetic faults, and rotated blocks with associated triangular openings. The damage formed at the mode III tips of strike-slip faults (e.g. observed in cliff sections) are classified as wall damage zones, because the damage zone structures are distributed along a fault trace in map view. Mixed-mode tips are likely to show characteristics of both mode II and mode III tips. Linking damage zones are developed at steps between two sub-parallel faults, and the structures developed depend on whether the step is extensional or contractional. Extension fractures and pull-aparts typically develop in extensional steps, whilst solution seams, antithetic faults and synthetic faults commonly develop in contractional steps. Rotated blocks, isolated lenses or strike-slip duplexes may occur in both extensional and contractional steps. Damage zone geometries and structures are strongly controlled by the location around a fault, the slip mode at a fault tip, and by the evolutionary stage of the fault. Although other factors control the nature of damage zones (e.g. lithology, rheology and stress system), the three-dimensional fault geometry and slip mode at each tip must be considered to gain an understanding of damage zones around faults.

  10. Fault zone fabric and fault weakness.

    PubMed

    Collettini, Cristiano; Niemeijer, Andr; Viti, Cecilia; Marone, Chris

    2009-12-17

    Geological and geophysical evidence suggests that some crustal faults are weak compared to laboratory measurements of frictional strength. Explanations for fault weakness include the presence of weak minerals, high fluid pressures within the fault core and dynamic processes such as normal stress reduction, acoustic fluidization or extreme weakening at high slip velocity. Dynamic weakening mechanisms can explain some observations; however, creep and aseismic slip are thought to occur on weak faults, and quasi-static weakening mechanisms are required to initiate frictional slip on mis-oriented faults, at high angles to the tectonic stress field. Moreover, the maintenance of high fluid pressures requires specialized conditions and weak mineral phases are not present in sufficient abundance to satisfy weak fault models, so weak faults remain largely unexplained. Here we provide laboratory evidence for a brittle, frictional weakening mechanism based on common fault zone fabrics. We report on the frictional strength of intact fault rocks sheared in their in situ geometry. Samples with well-developed foliation are extremely weak compared to their powdered equivalents. Micro- and nano-structural studies show that frictional sliding occurs along very fine-grained foliations composed of phyllosilicates (talc and smectite). When the same rocks are powdered, frictional strength is high, consistent with cataclastic processes. Our data show that fault weakness can occur in cases where weak mineral phases constitute only a small percentage of the total fault rock and that low friction results from slip on a network of weak phyllosilicate-rich surfaces that define the rock fabric. The widespread documentation of foliated fault rocks along mature faults in different tectonic settings and from many different protoliths suggests that this mechanism could be a viable explanation for fault weakening in the brittle crust. PMID:20016599

  11. Faulting in southwest Indiana

    SciTech Connect

    Ault, C.H.; Sullivan, D.M.

    1982-10-01

    Faults of the Wabash Valley Fault System, faults in Perry and Spencer Counties, Indiana, and the Mt. Carmel Fault are of the normal type and high angle and occur as single fault planes or as well-defined compound faults as much as 50 miles long with displacements ranging from a few feet to more than 400 feet. The Wabash faults and those in Perry and Spencer Counties were formally mapped, described, and named for the first time. Although supporting deep-drilling data are sparse, the Wabash and Mt. Carmel faults are probably present at depth, where they may form major structural alignments in basement rocks. No past studies have associated earthquake centers with any of the faults. The Wabash and Perry and Spencer County faults are post-Pennsylvanian and pre-Pleistocene in age. Early movement on the Mt. Carmel Fault is post-Valmeyeran, possibly Chesterian in age. The Wabash faulting is probably related to the regional tectonics that produced the New Madrid disturbance, but it is not a direct continuation of New Madrid faulting across the Rough Creek Fault Zone. The Mt. Carmel Fault may be associated with the hinge line of the eastern shelf of the Illinois Basin.

  12. Structure and sediment budget of Yinggehai-Song Hong basin, South China Sea: Implications for Cenozoic tectonics and river basin reorganization in Southeast Asia

    NASA Astrophysics Data System (ADS)

    Lei, Chao; Ren, Jianye; Sternai, Pietro; Fox, Matthew; Willett, Sean; Xie, Xinong; Clift, Peter D.; Liao, Jihua; Wang, Zhengfeng

    2015-08-01

    The temporal link between offshore stratigraphy and onshore topography is of key importance for understanding the long-term surface evolution of continental margins. Here we present a grid of regional, high-quality reflection seismic and well data to characterize the basin structure. We identify fast subsidence of the basin basement and a lack of brittle faulting of the offshore Red River fault in the Yinggehai-Song Hong basin since 5.5 Ma, despite dextral strike-slip movement on the onshore Red River fault. We calculate the upper-crustal, whole-crustal, and whole-lithospheric stretching factors for the Yinggehai-Song Hong basin, which show that the overall extension observed in the upper crust is substantially less than that observed for the whole crust or whole lithosphere. We suggest that fast basement subsidence after 5.5 Ma may arise from crustal to lithospheric stretching by the regional dynamic lower crustal/mantle flow originated by collision between India-Eurasia and Indian oceanic subduction below the Eurasian margin. In addition, we present a basin wide sediment budget in the Yinggehai-Song Hong basin to reconstruct the sedimentary flux from the Red River drainage constrained by high-resolution age and seismic stratigraphic data. The sediment accumulation rates show a sharp increase at 5.5 Ma, which suggests enhanced onshore erosion rates despite a slowing of tectonic processes. This high sediment supply filled the accommodation space produced by the fast subsidence since 5.5 Ma. Our data further highlight two prominent sharp decreases of the sediment accumulation at 23.3 Ma and 12.5 Ma, which could reflect a loss of drainage area following headwater capture from the Paleo-Red River. However, the low accumulation rate at 12.5 Ma also correlates with drier and therefore less erosive climatic conditions.

  13. Ductile and Brittle Neogene Deformation of Late Permian Orthogneiss in the Northern Ailao Shan-Red River Shear Zone: View from the Xuelong Shan Block

    NASA Astrophysics Data System (ADS)

    Wintsch, R. P.; Yi, D.; Yi, K.; Wang, Q. F.; Wang, G. H.

    2014-12-01

    The orthogneisses in the core of the Xuelong Shan block are surrounded by ductile and then brittle fault rocks. This lens-shape block is in fault contact with Triassic marbles on the eastern margin and Jurassic-Cretaceous mudstones on the western margin. The rocks in the core of the Xuelong Shan block contain multiply foliated feldspathic orthogneisses with local amphibolites, largely overprinted by protomylonitic deformation. Foliation strengthens to the east to become mylonites and ultramylonites, with a 30 m wide zone of loosely cemented fault breccia adjacent to brittlely faulted Triassic marbles. In contrast, the rocks to the west are dominated by brittle deformation, with mylonites becoming cataclasites and then breccias facing the mudstones to the east. Well-foliated phyllonites are locally present within the cataclasites. Early S1 gneissosity striking ENE are recognized only in the interior protomylonite. In the east, the dominate mylonitic S2 foliation strikes 340° with a moderate dip to the east, and an L2 mineral stretching lineation plunges gently north. However, in the west S2 cleavage is transposed into a NNW trending schistosity that dips steeply to the ENE, with down-dip mineral stretching lineations. Whole rock chemistry indicates a granitic to granodioritic protolith for all the rocks including the ultramylonites, but also suggests the progressive loss of alkalis with increasing deformation. Trace element compositions show these rocks lie in the volcanic arc/syn-collisional granite field. U-Pb SHRIMP ages show an Early Triassic age for these granite, with possible Middle Permian inheritance in some cores. These ages are consistent with the period of the closure of the northern Paleo-Tethys ocean. Metamorphic rim ages of ~ 30 Ma record a small amount of zircon dissolution/precipitation probably associated with the Oligocene ductile deformation that produced the upper greenschist facies mylonites. These results support the geologic history of the ASRRSZ based on data obtained in the southern Diancang Shan block. Permian granitoids were intruded and ductily deformed in the Early Triassic. The left lateral shearing that brought these blocks to the surface was delayed until the Neogene extrusion of the Indochina block.

  14. Preliminary map showing freshwater heads for the Red River Formation, Bighorn Dolomite, and equivalent rocks of Ordovician age in the Northern Great Plains of Montana, North Dakota, South Dakota, and Wyoming

    USGS Publications Warehouse

    Miller, W. Roger; Strausz, S.A.

    1980-01-01

    A map showing freshwater heads for the Ordovician Red River Formation, Bighorn Dolomite, and equivalent rocks has been prepared as part of a study to determine the water-resources potential of the Mississippian Madison Limestone and associated rocks in the Northern Great Plains of Montana, North and South Dakota, and Wyoming. Most of the data used to prepare the map are from drill-stem tests of exploration and development wells drilled by the petroleum industry from 1964 to 1978. A short explanation describes the seven categories of reliability used to evaluate the drill-stem-test data and identifies several factors that might explain the apparent anomalous highs and lows on the potentiometric surface. The map is at a scale of 1:1,000 ,000 and the potentiometric contour interval is 100 feet. (USGS)

  15. Architecture and sedimentary facies evolution in a delta stack controlled by fault growth (Betic Cordillera, southern Spain, late Tortonian)

    NASA Astrophysics Data System (ADS)

    García-García, Fernando; Fernández, Juan; Viseras, César; Soria, Jesús M.

    2006-03-01

    Tectonic control is revealed in various ways (synsedimentary deformation structures, facies, architecture) in the coarse-grained delta systems that developed in the southeastern margin of the Guadix Basin, an intramontane basin in the central sector of the Betic Cordillera, Spain, during the late Tortonian (Miocene). Vertical trends in the architecture of the deltaic succession (230 m thick) show changes in the stratal stacking pattern related to the variation in time in subsidence rates (in accommodation space). A period of high subsidence controlled by a normal growth fault began at the base of the succession, producing retrogradational units representing Gilbert-type delta systems onlapped by shallow platform calcarenites. A period of low subsidence followed, controlled by growth of a listric fault producing aggradational units representing shoal-water deltas capped by red algal biostromes. A non-subsidence period and decrease in accommodation space at the top of the succession (sediment supply remained constant) produced progradational deltas. The manuscript focuses on the part of the succession where the delta deposits show the effects of extensional tectonics, a listric growth fault and its rollover, on delta development. The progressive increase in accommodation space inherent in fault growth controlled the style of delta sedimentation in the river mouth. Gilbert-type deltas developed during periods of increase in subsidence rates and shoal-water deltas during periods of decrease in subsidence rates. Horizontal trends in the architecture of the delta lobes show changes in the stratal stacking pattern affected by differential subsidence and pre-existing basin-floor topography. Periods of increase in subsidence rates near the fault scarp correlate with accommodation space kept constant, thinning of the units and shoal-water deltas development over the rollover, away from the fault scarp.

  16. Paleoseismology of the Mt. Narryer Fault Zone, West Central Western Australia: a Multi-Segment Intraplate Fault System

    NASA Astrophysics Data System (ADS)

    Whitney, B. B.; Clark, D.; Hengesh, J.

    2014-12-01

    The Western Australia shear zone (WASZ) is a 2000 km long fault system within the intraplate region of Australia. A paleoseismological study of faults and fault-related folds comprising the Mount Narryer fault zone (MNfz) in the southern WASZ reveals a late Quaternary history of repeated morphogenic earthquake occurrence that has profoundly influenced the planform and course of the Murchison, Roderick, and Sanford Rivers. Folding in the near surface sediments is the predominant style of surface expression of reactivated basement faults which is consistent with other neotectonic structures throughout the Western Australia shear zone. CRN and OSL estimates of exposure and burial ages of fault-related folds and fold derived colluvium provide constraint on Late Quaternary slip rates on the underlying faults of ~0.05 - 0.1 mm/a. In the case of the Roderick River fault scarp, 2-3m high tectonic risers separating inset terraces where the Murchison River crosses the scarp are consistent with multiple late Quaternary seismic events on the order of magnitude Mw 7.1-7.3. Mid-Pleistocene ages of tectonically deformed strata in the MNfz are consistent with the timing of collision between the Australian extended margin and Savu-Rote ridge 0.2-1.8 Ma.

  17. Late Quaternary faulted landforms characteristics on the Tumen-Jiazhu village segment of Luoyunshan piedmont fault

    NASA Astrophysics Data System (ADS)

    Sun, C.; Xie, X.; Xu, J.

    2013-12-01

    Luoyunshan piedmont fault is located west of Linfen basin, controlling the western border of the basin. Based on the fault 1:50000 geological mapping, river and gully terraces and piedmont faulted landforms survey, this paper mainly introduces late Quaternary faulted landforms characteristics on the Tumen-Jiazhu village segment of Luoyunshan piedmont fault. Luoyunshan piedmont alluvial-pluvial fans are divided into three stages, named alluvial-pluvial fans D1, D2 and D3. The gullies on the upthrown plate of Luoyunshan piedmont fault has five terraces: T1~T5. Alluvial-pluvial fans D1 and terraces T1 and T2 formed in the early and middle Holocene. Alluvial-pluvial fans D2 and terraces T3 formed in the middle-late stage of late Pleistocene. Alluvial-pluvial fans D3 and terraces T4 and T5 formed in the middle-late stage of middle Pleistocene. Faulted landforms characteristics on different parts of the middle segment of the Luo Yunshan piedmont fault are different. The dislocation of alluvial-pluvial fans D1 is about 2.9m and 3m respectively in the Xifanggou area and the piedmont of southwest of Yukou village, Jindian town. The dislocation of alluvial-pluvial fans D2 is about 2.5m, 4m, 6m and 7.7m respectively in the southwest of Puzi village, Tumen town, piedmont of west of Yangjiazhuang village, west of Jingcun village and piedmont of southwest of Langquangou, Xiangling town. The faulted landforms on the Tumen-Jiazhu village segment of Luoyunshan piedmont fault are obvious. The latest activity times of the fault is Holocene. The latest activity times of Tumen segment and Longci segment of the fault are early Holocene and middle-late Holocene respectively. Since the Middle-Late Pleistocene an activity rate of the middle segment of Luoyunshan piedmont fault is 0.18~0.54mm/yr, and activity showed an increasing trend from north to south. Since Early-Middle Holocene it is 0.4~0.9mm/yr, and fault activities mainly concentrated on the segment from Xifanggou to Yukou village. An increasing trend of the activity rate of the middle segment of Luoyunshan piedmont fault from the Middle-Late Pleistocene to Holocene, it is in good agreement with an increasing trend of the uplift rate of the terraces on the upthrown plate of the fault from the Middle-Late Pleistocene to Holocene and the sedimentation rate of Linfen basin which also has an increasing trend from the Late Pleistocene to Holocene.

  18. Identification and interpretation of tectonic features from ERTS-1 imagery. [geological faults in California mountain regions

    NASA Technical Reports Server (NTRS)

    Abdel-Gawad, M. (Principal Investigator)

    1974-01-01

    The author has identified the following significant results. ERTS-1 imagery shows that the southern segment of the San Gabriel fault which controls the west fork of the San Gabriel River is strikingly similar to the Mill Creek Fault in the San Bernardino Mountains. It has also been noted that there is a similarity between the Sierra Madre thrust zone of the San Gabriel Mountains to the Banning thrust of the San Bernardino Mountains. This suggests that the southern San Gabriel fault was once continuous with the Mill Creek fault. When the San Bernardino Mountain block is theoretically moved to the northwest along the San Jacinto fault so that the Mill Creek fault is aligned with the southern part of the San Gabriel fault, it was found that the four transverse fault segments become aligned with the Pinto Fault on the east and with the Raymond-Santa Monica Malibu Fault zone on the west. The reconstruction identifies a continuous zone of transverse faulting extending from the Colorado River Desert to the Pacific. It seems likely that the entire fault zone was once a continuous left-lateral shear. This Anacapa Shear has probably been subjected to a 50 km left lateral movement. This analysis strongly indicates that the tectonic history of the Transverse Range has been characterized by left lateral shear on transverse faults and right lateral shear on the San Andreas fault system.

  19. Fault Mapping in Haiti

    USGS geologist Carol Prentice surveying features that have been displaced by young movements on the Enriquillo fault in southwest Haiti.  The January 2010 Haiti earthquake was associated with the Enriquillo fault....

  20. Red Sky with Red Mesa

    ScienceCinema

    None

    2014-06-23

    The Red Sky/Red Mesa supercomputing platform dramatically reduces the time required to simulate complex fuel models, from 4-6 months to just 4 weeks, allowing researchers to accelerate the pace at which they can address these complex problems. Its speed also reduces the need for laboratory and field testing, allowing for energy reduction far beyond data center walls.

  1. Red Sky with Red Mesa

    SciTech Connect

    2011-04-14

    The Red Sky/Red Mesa supercomputing platform dramatically reduces the time required to simulate complex fuel models, from 4-6 months to just 4 weeks, allowing researchers to accelerate the pace at which they can address these complex problems. Its speed also reduces the need for laboratory and field testing, allowing for energy reduction far beyond data center walls.

  2. Red Capes, Red Herrings, and Red Flags.

    ERIC Educational Resources Information Center

    Fiske, Donald W.

    The argument that the personality structures obtained from retrospective ratings reflect semantic similarity structures has been as provocative as a red cape in the bull ring. High congruence between those two kinds of structures seems well established. What is less clear is how and why those structures differ from that for immediate judgments of…

  3. Using fluvial channel morphology to obtain the neotectonic characteristics of the Liuchia fault, an important active structure in southwestern Taiwan

    NASA Astrophysics Data System (ADS)

    Shyu, J. H.; Du, K.

    2013-12-01

    The Liuchia fault in southwestern Taiwan has been considered as one of the major active faults in the active Taiwan orogen. It is identified by its clear geomorphic features, and forms a major geologic boundary of Taiwan's Western Foothills. No unanimous historical evidence for seismic activity of the Liuchia fault exists, thus the fault poses large earthquake hazard potentials for the populous southwestern Taiwan. Here we attempted to analyze the characteristics of the fault from fluvial channel morphology of the Kueichung River that flows across the fault. We also calculated actual river incision rates from the age of river terraces along the river to obtain the rock uplift rates of the hanging-wall block of the fault. We have obtained a detailed river long profile of the Kueichung River from surveys using RTK-GPS, and a channel width profile from actual field measurements using a Laser Rangefinder. The fluvial channel morphology of the Kueichung River appears to have been affected by active folding in the hanging-wall block of the Liuchia fault. Such active deformation pattern is also evident from river incision rate patterns. Combining these different datasets, we constructed a realistic model of the subsurface geometry of the Liuchia fault in southwestern Taiwan, and calculated the long-term slip rates of this important active structure in southwestern Taiwan.

  4. Field and Laboratory Data From an Earthquake History Study of Scarps of the Lake Creek-Boundary Creek Fault Between the Elwha River and Siebert Creek, Clallam County, Washington

    USGS Publications Warehouse

    Nelson, Alan R.; Personius, Stephen F.; Buck, Jason; Bradley, Lee-Ann; Wells, Ray E.; Schermer, Elizabeth R.

    2007-01-01

    Fault scarps recently discovered on Airborne Laser Swath Mapping (ALSM; also known as LiDAR) imagery show Holocene movement on the Lake Creek-Boundary Creek fault on the north flank of the Olympic Mountains of northwestern Washington State. Such recent movement suggests the fault is a potential source of large earthquakes. As part of the effort to assess seismic hazard in the Puget Sound region, we map scarps on ALSM imagery and show primary field and laboratory data from backhoe trenches across scarps that are being used to develop a latest Pleistocene and Holocene history of large earthquakes on the fault. Although some scarp segments 0.5-2 km long along the fault are remarkably straight and distinct on shaded ASLM imagery, most scarps displace the ground surface <1 m, and, therefore, are difficult to locate in dense brush and forest. We are confident of a surface-faulting or folding origin and a latest Pleistocene to Holocene age only for scarps between Lake Aldwell and the easternmost fork of Siebert Creek, a distance of 22 km. Stratigraphy in five trenches at four sites help determine the history of surface-deforming earthquakes since glacier recession and alluvial deposition 11-17 ka. Although the trend and plunge of indicators of fault slip were measured only in the weathered basalt exposed in one trench, upward-splaying fault patterns and inconsistent displacement of successive beds along faults in three of the five trenches suggest significant lateral as well as vertical slip during the surface-faulting or folding earthquakes that produced the scarps. Radiocarbon ages on fragments of wood charcoal from two wedges of scarp-derived colluvium in a graben-fault trench suggest two surface-faulting earthquakes between 2,000 and 700 years ago. The three youngest of nine radiocarbon ages on charcoal fragments from probable scarp-derived colluvum in a fold-scarp trench 1.2 km to the west suggest a possible earlier surface-faulting earthquake less than 5,000 years ago.

  5. Quantitative fault seal prediction

    SciTech Connect

    Yielding, G.; Freeman, B.; Needham, D.T.

    1997-06-01

    Fault seal can arise from reservoir/nonreservoir juxtaposition or by development of fault rock having high entry pressure. The methodology for evaluating these possibilities uses detailed seismic mapping and well analysis. A first-order seal analysis involves identifying reservoir juxtaposition areas over the fault surface by using the mapped horizons and a refined reservoir stratigraphy defined by isochores at the fault surface. The second-order phase of the analysis assesses whether the sand/sand contacts are likely to support a pressure difference. We define two types of lithology-dependent attributes: gouge ratio and smear factor. Gouge ratio is an estimate of the proportion of fine-grained material entrained into the fault gouge from the wall rocks. Smear factor methods (including clay smear potential and shale smear factor) estimate the profile thickness of a shale drawn along the fault zone during faulting. All of these parameters vary over the fault surface, implying that faults cannot simply be designated sealing or nonsealing. An important step in using these parameters is to calibrate them in areas where across-fault pressure differences are explicitly known from wells on both sides of a fault. Our calibration for a number of data sets shows remarkably consistent results, despite their diverse settings (e.g., Brent province, Niger Delta, Columbus basin). For example, a shale gouge ratio of about 20% (volume of shale in the slipped interval) is a typical threshold between minimal across-fault pressure difference and significant seal.

  6. The San Andreas Fault

    USGS Publications Warehouse

    Schulz, Sandra S.; Wallace, Robert E.

    1993-01-01

    The presence of the San Andreas fault was brought dramatically to world attention on April 18, 1906, when sudden displacement along the fault produced the great San Francisco earthquake and fire. This earthquake, however, was but one of many that have resulted from episodic displacement along the fault throughout its life of about 15-20 million years.

  7. The Lower Tagus Valley (LTV) Fault System

    NASA Astrophysics Data System (ADS)

    Besana-Ostman, G. M.; Fereira, H.; Pinheiro, A.; Falcao Flor, A. P.; Nemser, E.; Villanova, S. P.; Fonseca, J. D.

    2010-05-01

    The LTV fault and its associated historical seismic activity have been the focus of several scientific studies in Portugal. There are at least three historical earthquakes associated with the LTV fault, in 1344, 1531, and 1909. Magnitude estimates for these earthquakes range from 6.5 to 7.0. They caused widespread damage throughout the Lower Tagus Valley region with intensities ranging from VIII to X from Lisbon to Entroncamento. During the great 1755 earthquake, the LTV fault was likewise proposed to have ruptured coseismically. The Azambuja fault or the Vila Franca de Xira fault are suggested origins of the 1909 earthquake. Trenching activities together with borehole data analyses, geophysical investigations, and seismic hazard assessments were undertaken in the LTV in the recent years. Complex trench features along the excavated sections were argued to be either fault- or erosion-related phenomena. Borehole data and seismic profiles indicate subsurface structures within the Lower Tagus Valley and adjacent areas. Furthermore, recent attempts to improve seismic hazard assessment indicate that the highest values in Portugal for 10% probability of exceedance in 50 years correspond with the greater Lisbon area, with the LTV fault as the most probable source. Considering the above, efforts are being made to acquire more information about the location of the LTV seismic source taking into account the presence of extensive erosion and/or deposition processes within the valley, densely populated urban areas, heavily forested regions, and flooded sections such as the Tagus estuary. Results from recent mapping along the LTV reveal surface faulting that left-laterally displaced numerous geomorphic landforms within the Lower Tagus River valley. The mapped trace shows clear evidence of left-lateral displacement and deformation within the valley transecting the river, its tributaries, and innumerable young terraces. The trace has been mapped by analyzing topographic maps, aerial photographs, and river systems together with other remotely-sensed data. Active fault-related features that were identified include fault scarps, pressure ridges, pull-apart basin, saddles, and linear valleys. Limited ocular investigation has also been undertaken to verify modifications that post-date the aerial photos, quantify both elevation differences across the fault, and possibly evaluate the cumulative lateral displacements. Thus, the newly-identified traces of an active fault in the LTV corresponds with a left-lateral fault along the Lower Tagus floodplains striking parallel to the principal structural trend (NNE-SSW) in the region. This trace clearly indicates continued tectonic movement along the LTV fault during the Holocene. Taking into account the newly-mapped location and length of the active trace, trenching work is being planned to determine recurrence intervals along the LTV fault while further mapping of its possible extension and other related active structures are underway. Moreover, new estimates of slip rate along this structure will result from this study and can be used for an improved seismic hazard assessment for the region.

  8. Fault recovery characteristics of the fault tolerant multi-processor

    NASA Technical Reports Server (NTRS)

    Padilla, Peter A.

    1990-01-01

    The fault handling performance of the fault tolerant multiprocessor (FTMP) was investigated. Fault handling errors detected during fault injection experiments were characterized. In these fault injection experiments, the FTMP disabled a working unit instead of the faulted unit once every 500 faults, on the average. System design weaknesses allow active faults to exercise a part of the fault management software that handles byzantine or lying faults. It is pointed out that these weak areas in the FTMP's design increase the probability that, for any hardware fault, a good LRU (line replaceable unit) is mistakenly disabled by the fault management software. It is concluded that fault injection can help detect and analyze the behavior of a system in the ultra-reliable regime. Although fault injection testing cannot be exhaustive, it has been demonstrated that it provides a unique capability to unmask problems and to characterize the behavior of a fault-tolerant system.

  9. Slab break-off influence on the formation of the major intra-continental faulting systems during India-Asia convergence

    NASA Astrophysics Data System (ADS)

    Clark, M. K.; Avdeev, B.; Duvall, A. R.; Staisch, L. M.; Niemi, N. A.; Farley, K. A.

    2011-12-01

    Comparing global tomographic images and Asian tectonics reconstruction, allows formulating hypotheses on how deep subduction and indentation tectonics are coupled that we tested by doing numerical models which show the link between slab breakoff event and initiation of strike-slip faults in the upper plate. The long term evolution of Indian lithosphere during the indentation process has been deduced from remnants of slabs in the mantle shown by P-waves global tomography. A complete breakoff occurs at the transition between the Tethys oceanic subduction and the Indian continental one (OCB), then the Indian lithosphere resumes subducting, but with drastic variation of timing from west to east, late subduction far north of the trench to the west, early subduction following by a second breakoff more to the east. The long term evolution of the Asian continental deformation constrains the age and style of the upper plate deformation during the collision. Drastic changes occur in the fault pattern, with successive strike-slip faults crossing the entire Asian continent. The Bangong-Red River initiated early in the collision time, to the south of the collision zone, while the Altyn Tagh fault initiates later in the collision time, to the north of the collision zone. We perform self-consistent three-dimensional numerical models of coupled subducting/upper plates in an ambient mantle. We find that when slab detaches at the OCB, the subduction of the buoyant continent progressively decreases the driving force available, yet transient stresses propagate far into the upper plate interiors, localising along a belt at a high angle with the trench. The large stresses in the upper plate interiors propagate at large distance from the margin with a trend similar to the major lithospheric faults of Asia. The successive breakoff episodes evidenced using global tomography likely provided the conditions for large stress surge in the Asian lithosphere that resulted in the formation of the long-lived major intra-continental faulting systems, first of the Red River and second of the Altyn Tagh. The transient coupling gradients at the trench caused by the breakoff events have generated successive localised stress pulses which provide the conditions for episodic nucleation of lithospheric faults within the Asian continent and their link to deep processes.

  10. Red leaks

    NASA Astrophysics Data System (ADS)

    Chiaberge, Marco

    2007-07-01

    The aim of this program is to measure the red leaks in the 8 WFPC2 UV filters {F122M, F300W, F255W, F218W, F185W, F170W, F160BW, F122M}. We will use red crossing filters to isolate and directly measure the leaks. No observations of this kind have ever been performed with WFPC2 to check the red leaks in the UV filters, most of them being extensively used by GO/GTO programs. A previous calibration program has only imaged spectrophotometric standard stars with UV filters {no filter crossing} thus the red leak is hard to measure using those data. The throughput curves for some of the UV filters {F300W, F255W, F218W, F185W} in synphot have incomplete information, some of them have gaps in the measurements as wide as 3000A.

  11. Red Clover

    MedlinePlus

    ... for menopausal hot flashes: systematic review and meta-analysis . Journal of the American Medical Association . 2006;295(17):2057–2071. Red clover. Natural Medicines Comprehensive Database Web site. Accessed at www.naturaldatabase.com on July ...

  12. Tectonics of the Levant fault system

    NASA Astrophysics Data System (ADS)

    Klinger, Yann

    2015-07-01

    In June 2013, for the second time, an international workshop dedicated to the tectonics of the Levant fault system and the Arabic plate was held in Paris. During two days, this meeting gathered researchers from 19 institutions and 12 countries, with 24 presentations. During this meeting, a large variety of topics were addressed, ranging from new insights into the geodynamics of the Red Sea to earthquake history along the Dead Sea fault. A key point of this meeting was actually to gather contributions focused on the same object, here the Levant fault system, but with different perspectives, to foster new collaborations and research projects. In line with this idea, several presentations were actually dealing with issues related to the palaeoclimate of this specific region, engineering issues about earthquake destructions, or the impact of the Dead Sea active tectonics on the evolution of hominins, aside from general tectonics.

  13. Complex Faulting within the New Madrid Seismic Zone

    NASA Astrophysics Data System (ADS)

    Deshon, H. R.; Powell, C. A.; Magnani, M.; Bisrat, S. T.

    2010-12-01

    Relative relocations derived using double-difference tomography techniques reveal a complex sequence of faulting within the New Madrid Seismic Zone (NMSZ) and upper Mississippi Embayment. The majority of NMSZ seismicity recorded over the last 30 years occurs along four limbs: 1) a NE-SW trending dextral strike-slip fault, termed the Axial fault, coincident with the central valley of the Cambrian Reelfoot Rift system; 2) the SE-NW trending Reelfoot thrust fault; 3) a E-W trending left lateral strike-slip fault extending off of the northern terminus of the Reelfoot fault, here termed New Madrid west; and 4) a NE-SW dextral strike-slip fault also extending off of the northern terminus of the Reelfoot fault, here termed New Madrid north. Each of these segments is thought to have ruptured during the 1811-1812 large earthquake sequence. A fifth segment, the Bootheel lineament, is marked by 1811-1812 related liquefaction features but appears largely aseismic, though we suggest there are at least five events in the catalog associated with this feature. Geological and geophysical evidence across the embayment suggests that the region is crossed by additional faults at shallow depths (<1-2 km), while seismicity is generally confined to the 3-20 km depth range. Here we present relative relocations derived using catalog and waveform cross-correlation differential times of the 1989-1992 local PANDA network and the 1995-2010 Cooperative New Madrid Seismic Network. We show that the four known seismic lineations exhibit internal complexity. For example, New Madrid north is composed of two parallel faults rather then a single fault, and seismicity associated with the Axial lineation exhibits temporal changes along strike and becomes spatially more diffuse south of the Axial fault/Bootheel lineament intersection. Seismicity along the southern Reelfoot fault does not define a dipping plane consistent with thrust faulting, unlike the northern Reelfoot fault, and is associated with anomalously low P wave velocities. Swarm activity along the southern portion of the Reelfoot fault and near the northern portion of the Reelfoot fault terminus may be related to fault intersections within this complicated transpressional system. Recent reflection data of the upper 1 km imaged along the Mississippi River indicate that both the north termini of the Reelfoot and Axial faults are characterized by splay faulting, while at depth microseismicity is planar. Absolute and relative error will be assessed by computing locations within two 3D P and S wave velocity models of the study area, using finite difference and pseudo-bending ray tracing approaches, and jack-knife approaches to test dependence on network geometry.

  14. Robust Fault Detection

    NASA Technical Reports Server (NTRS)

    Guo, Ten-Huei (Technical Monitor); Collins, Emmanuel G.; Song, Tinglun; Curry, Tramone; Selekwa, Majura

    2003-01-01

    This research used mixed structured singular value theory to develop new estimator (or observer) based approaches to fault detection for dynamic systems. The initial developments were based on minimizing the H-infinity, I-1 and H2 system norms. The resultant fault detection algorithms were each shown to be successful, but the fault detection algorithm based on the I-1 norm was best able to detect abrupt faults. This latter technique was further improved by using fuzzy logic for the fault evaluation. Based on an anomaly observed in this research and apparently ignored in the literature, current research focuses on the determination of a fault using a norm of the change in the residual (the difference between the output of the system and observer) and not simply a norm of the residual itself. This research may lead to a fundamental contribution to research in fault detection and isolation.

  15. Questa baseline and pre-mining ground-water quality investigation. 5. Well installation, water-level data, and surface- and ground-water geochemistry in the Straight Creek drainage basin, Red River Valley, New Mexico, 2001-03

    USGS Publications Warehouse

    Naus, Cheryl A.; McCleskey, R. Blaine; Nordstrom, D. Kirk; Donohoe, Lisa C.; Hunt, Andrew G.; Paillet, Frederick L.; Morin, Roger H.; Verplanck, Philip L.

    2005-01-01

    The U.S. Geological Survey, in cooperation with the New Mexico Environment Department, is investigating the pre-mining ground-water chemistry at the Molycorp molybdenum mine in the Red River Valley, northern New Mexico. The primary approach is to determine the processes controlling ground-water chemistry at an unmined, off-site, proximal analog. The Straight Creek drainage basin, chosen for this purpose, consists of the same quartz-sericite-pyrite altered andesitic and rhyolitic volcanic rock of Tertiary age as the mine site. The weathered and rugged volcanic bedrock surface is overlain by heterogeneous debris-flow deposits that interfinger with alluvial deposits near the confluence of Straight Creek and the Red River. Pyritized rock in the upper part of the drainage basin is the source of acid rock drainage (pH 2.8-3.3) that infiltrates debris-flow deposits containing acidic ground water (pH 3.0-4.0) and bedrock containing water of circumneutral pH values (5.6-7.7). Eleven observation wells were installed in the Straight Creek drainage basin. The wells were completed in debris-flow deposits, bedrock, and interfingering debris-flow and Red River alluvial deposits. Chemical analyses of ground water from these wells, combined with chemical analyses of surface water, water-level data, and lithologic and geophysical logs, provided information used to develop an understanding of the processes contributing to the chemistry of ground water in the Straight Creek drainage basin. Surface- and ground-water samples were routinely collected for determination of total major cations and selected trace metals; dissolved major cations, selected trace metals, and rare-earth elements; anions and alkalinity; and dissolved-iron species. Rare-earth elements were determined on selected samples only. Samples were collected for determination of dissolved organic carbon, mercury, sulfur isotopic composition (34S and 18O of sulfate), and water isotopic composition (2H and 18O) during selected samplings. One set of ground-water samples was collected for helium-3/tritium and chlorofluorocarbon (CFC) age dating. Several lines of evidence indicate that surface water is the primary input to the Straight Creek ground-water system. Straight Creek streamflow and water levels in wells closest to the apex of the Straight Creek debris fan and closest to Straight Creek itself appear to respond to the same seasonal inputs. Oxygen and hydrogen isotopic compositions in Straight Creek surface water and ground water are similar, and concentrations of most dissolved constituents in most Straight Creek surface-water and shallow (debris-flow and alluvial) aquifer ground-water samples correlate strongly with sulfate (concentrations decrease linearly with sulfate in a downgradient direction). After infiltration of surface water, dilution along the flow path is the dominant mechanism controlling ground-water chemistry. However, concentrations of some constituents can be higher in ground water than can be accounted for by concentrations in Straight Creek surface water, and additional sources of these constituents must therefore be inferred. Constituents for which concentrations in ground water can be high relative to surface water include calcium, magnesium, strontium, silica, sodium, and potassium in ground water from debris-flow and alluvial aquifers and manganese, calcium, magnesium, strontium, sodium, and potassium in ground water from the bedrock aquifer. All ground water is a calcium sulfate type, often at or near gypsum saturation because of abundant gypsum in the aquifer material developed from co-existing calcite and pyrite mineralization. Calcite dissolution, the major buffering mechanism for bedrock aquifer ground water, also contributes to relatively higher calcium concentrations in some ground water. The main source of the second most abundant cation, magnesium, is probably dissolution of magnesium-rich carbonates or silicates. Strontium may also be

  16. Analysis of high-resolution lidar digital topographic data along the Marlborough Fault System: The Awatere and Clarence faults, South Island, New Zealand

    NASA Astrophysics Data System (ADS)

    Zinke, R. W.; Dolan, J. F.; Rhodes, E. J.; Van Dissen, R. J.; Langridge, R.; Grenader, J.; McGuire, C. P.; Nicol, A.

    2014-12-01

    We analyze newly acquired lidar high-resolution digital topographic data to measure offset geomorphic markers along the Awatere and Clarence faults in the Marlborough Fault System, northern South Island, New Zealand. With an average shot density of ≥ 12 shots/m2, these lidar data, which were acquired for us by the US National Center for Airborne Laser Mapping (NCALM) and New Zealand Aerial Mapping, offer a uniquely detailed view of the topography along ~90 km of the Awatere fault and ~160 km of the Clarence fault, allowing us to measure geomorphic offsets ranging in size from ~1 m to 100s of meters. In this specific study, we examine offset river terraces at the well-known Saxton River site on the Awatere fault, and at Tophouse Road on the Clarence fault. By constraining the ages of those river terraces using post-IR IRSL (225 °C) single-grain K-feldspar dating protocols, we determine latest Pleistocene to late-Holocene slip histories of the Awatere and Clarence faults at those locations. This project is part of a broader effort to generate incremental slip rates and paleoearthquake ages from the four main faults that comprise the Marlborough Fault System with the goal of further understanding how mechanically complementary faults work together to accommodate relative plate motions.

  17. High resolution, shallow seismic reflection survey of the Pen Branch fault

    SciTech Connect

    Stieve, A.

    1991-05-15

    The purpose of this project, at the Savannah River River Site (SRS) was to acquire, process, and interpret 28 km (17.4 miles) of high resolution seismic reflection data taken across the trace of the Pen Branch fault and other suspected, intersecting north-south trending faults. The survey was optimized for the upper 300 ft of geologic strata in order to demonstrate the existence of very shallow, flat lying horizons, and to determine the depth of the fault or to sediments deformed by the fault. Field acquisition and processing parameters were selected to define small scale spatial variability and structural features in the vicinity of the Pen Branch fault leading to the definition and the location of the Pen Branch fault, the shallowest extent of the fault, and the quantification of the sense and magnitude of motion. Associated geophysical, borehole, and geologic data were incorporated into the investigation to assist in the determination of optimal parameters and aid in the interpretation.

  18. FTAPE: A fault injection tool to measure fault tolerance

    NASA Technical Reports Server (NTRS)

    Tsai, Timothy K.; Iyer, Ravishankar K.

    1995-01-01

    The paper introduces FTAPE (Fault Tolerance And Performance Evaluator), a tool that can be used to compare fault-tolerant computers. The tool combines system-wide fault injection with a controllable workload. A workload generator is used to create high stress conditions for the machine. Faults are injected based on this workload activity in order to ensure a high level of fault propagation. The errors/fault ratio and performance degradation are presented as measures of fault tolerance.

  19. FTAPE: A fault injection tool to measure fault tolerance

    NASA Technical Reports Server (NTRS)

    Tsai, Timothy K.; Iyer, Ravishankar K.

    1994-01-01

    The paper introduces FTAPE (Fault Tolerance And Performance Evaluator), a tool that can be used to compare fault-tolerant computers. The tool combines system-wide fault injection with a controllable workload. A workload generator is used to create high stress conditions for the machine. Faults are injected based on this workload activity in order to ensure a high level of fault propagation. The errors/fault ratio and performance degradation are presented as measures of fault tolerance.

  20. Isolability of faults in sensor fault diagnosis

    NASA Astrophysics Data System (ADS)

    Sharifi, Reza; Langari, Reza

    2011-10-01

    A major concern with fault detection and isolation (FDI) methods is their robustness with respect to noise and modeling uncertainties. With this in mind, several approaches have been proposed to minimize the vulnerability of FDI methods to these uncertainties. But, apart from the algorithm used, there is a theoretical limit on the minimum effect of noise on detectability and isolability. This limit has been quantified in this paper for the problem of sensor fault diagnosis based on direct redundancies. In this study, first a geometric approach to sensor fault detection is proposed. The sensor fault is isolated based on the direction of residuals found from a residual generator. This residual generator can be constructed from an input-output or a Principal Component Analysis (PCA) based model. The simplicity of this technique, compared to the existing methods of sensor fault diagnosis, allows for more rational formulation of the isolability concepts in linear systems. Using this residual generator and the assumption of Gaussian noise, the effect of noise on isolability is studied, and the minimum magnitude of isolable fault in each sensor is found based on the distribution of noise in the measurement system. Finally, some numerical examples are presented to clarify this approach.

  1. Fault tectonics and earthquake hazards in parts of southern California. [penninsular ranges, Garlock fault, Salton Trough area, and western Mojave Desert

    NASA Technical Reports Server (NTRS)

    Merifield, P. M. (Principal Investigator); Lamar, D. L.; Gazley, C., Jr.; Lamar, J. V.; Stratton, R. H.

    1976-01-01

    The author has identified the following significant results. Four previously unknown faults were discovered in basement terrane of the Peninsular Ranges. These have been named the San Ysidro Creek fault, Thing Valley fault, Canyon City fault, and Warren Canyon fault. In addition fault gouge and breccia were recognized along the San Diego River fault. Study of features on Skylab imagery and review of geologic and seismic data suggest that the risk of a damaging earthquake is greater along the northwestern portion of the Elsinore fault than along the southeastern portion. Physiographic indicators of active faulting along the Garlock fault identifiable in Skylab imagery include scarps, linear ridges, shutter ridges, faceted ridges, linear valleys, undrained depressions and offset drainage. The following previously unrecognized fault segments are postulated for the Salton Trough Area: (1) An extension of a previously known fault in the San Andreas fault set located southeast of the Salton Sea; (2) An extension of the active San Jacinto fault zone along a tonal change in cultivated fields across Mexicali Valley ( the tonal change may represent different soil conditions along opposite sides of a fault). For the Skylab and LANDSAT images studied, pseudocolor transformations offer no advantages over the original images in the recognition of faults in Skylab and LANDSAT images. Alluvial deposits of different ages, a marble unit and iron oxide gossans of the Mojave Mining District are more readily differentiated on images prepared from ratios of individual bands of the S-192 multispectral scanner data. The San Andreas fault was also made more distinct in the 8/2 and 9/2 band ratios by enhancement of vegetation differences on opposite sides of the fault. Preliminary analysis indicates a significant earth resources potential for the discrimination of soil and rock types, including mineral alteration zones. This application should be actively pursued.

  2. Late Quaternary faulting on the Manas and Hutubi reverse faults in the northern foreland basin of Tian Shan, China

    NASA Astrophysics Data System (ADS)

    Gong, Zhijun; Li, Sheng-Hua; Li, Bo

    2015-08-01

    The Tian Shan Range lies in the actively deforming part of the India-Asia collision zone. In the northern foreland basin of Tian Shan, the strata were intensively deformed by Cenozoic folding and faulting. Slip rate studies along these faults are important for understanding the dynamics of crustal deformation and evaluating the seismic hazards in the region. Two reverse faults (the Manas and Hutubi faults) in the northern foreland basin were investigated. Due to past faulting events along these faults, the terrace treads along the Manas River were ruptured, forming fault scarps several meters in height. Loess deposits were trapped and preserved at the surface ruptures along these scarps. The thickness of the trapped loess is dependent on the size of the ruptures. The minimum and maximum ages of these scarps are constrained by dating the loess preserved at the surface ruptures and the terrace treads, respectively, using the quartz optically stimulated luminescence (OSL) dating technique. Our dating results suggest that the loess trapped at the ruptures was deposited from the early to mid-Holocene at the Hutubi Fault, and from the mid- to late-Holocene at the Manas Fault. The vertical displacements of the faults were evaluated by measuring the topographic profiles across the investigated fault scarps using the differential global position system (DGPS). Our results suggest that, during the late Quaternary in the studied region, the vertical slip rates of the Manas Fault were between ˜ 0.74 mm /yr and ˜ 1.6 mm /yr, while the Hutubi Fault had a much lower vertical slip rate between ˜ 0.34 mm /yr and ˜ 0.40 mm /yr. The tectonic implications of our results are discussed.

  3. Active faulting and folding along the Jumilla Fault Zone, northeastern Betics, Spain

    NASA Astrophysics Data System (ADS)

    Van Balen, R. T.; Forzoni, A.; Van Dam, J. A.

    2015-05-01

    The Jumilla Fault Zone (JFZ) is an ENE-WSW topographic lineament in the external part of the eastern Betic Cordillera. It represents an active fault. Three small basins are aligned along the JFZ, the La Celia-, Alqueria- and Jumilla basins. The tectonic geomorphology of the La Celia- and Alqueria basins consists of folds, a set of normal fault scarps, strike-slip lineaments, fault-springs, tectonically-modified drainage lines and elevated gypsum/anhydrite diapirs. Two of the scarps are normal faults generated by the extensional collapse of one of the folds. The other scarps are secondary normal faults generated by transtensional left-lateral motions along the JFZ. Normal fault scarps that developed on conglomerates are considerably steeper (~ 30°) than those affecting softer marly materials (< 10°) as a consequence of their different erodibilities. Two natural springs reveal the sealing nature of the normal faults, which has resulted in a segmented groundwater system. These springs are the sources of the two largest ramblas (gullies) in the area. The onset of fault activity is constrained by the late Tortonian-Messinian age of the sedimentary rocks in the basins. Interbedded lavaflows and lamproitic dykes in the lacustrine sediments have been dated at 7.6-7.2 Ma. However, the morphology of fault scarps and relief of the diapirs suggest a younger age of the deformation. Results from modelling of fault scarp evolution indicate Middle Pleistocene and younger ages of faulting and scarp formation. Furthermore, in at least one of the fault scarps, Quaternary alluvial-pediment deposits are involved in the deformation. The drainage pattern anomalies and moderate earthquake activity (Mb 4.2) in the JFZ also indicate slow ongoing tectonic activity. In addition, the ENE prolongation of the JFZ (outside the study area) shows geodetic displacement rates of approximately 2 mm/year. We thus conclude that the JFZ is still active, despite the general lack of post-Messinian deposits in the studied basins. The discrepancy between the age of the tectonic landforms and the late Neogene age of the basin infill can be explained by an endo- to exhorheic change in the drainage system, due to the capture of the ancient basin lake system by tributaries of the nearby Segura river. The cessation of sedimentation in the basins resulted in the preservation of tectonic landforms.

  4. Estimating Water Storage Capacity of Existing and Potentially Restorable Wetland Depressions in a Subbasin of the Red River of the North

    USGS Publications Warehouse

    Gleason, Robert A.; Tangen, Brian A.; Laubhan, Murray K.; Kermes, Kevin E.; Euliss, Ned H.

    2007-01-01

    Executive Summary Concern over flooding along rivers in the Prairie Pothole Region has stimulated interest in developing spatially distributed hydrologic models to simulate the effects of wetland water storage on peak river flows. Such models require spatial data on the storage volume and interception area of existing and restorable wetlands in the watershed of interest. In most cases, information on these model inputs is lacking because resolution of existing topographic maps is inadequate to estimate volume and areas of existing and restorable wetlands. Consequently, most studies have relied on wetland area to volume or interception area relationships to estimate wetland basin storage characteristics by using available surface area data obtained as a product from remotely sensed data (e.g., National Wetlands Inventory). Though application of areal input data to estimate volume and interception areas is widely used, a drawback is that there is little information available to provide guidance regarding the application, limitations, and biases associated with such approaches. Another limitation of previous modeling efforts is that water stored by wetlands within a watershed is treated as a simple lump storage component that is filled prior to routing overflow to a pour point or gaging station. This approach does not account for dynamic wetland processes that influence water stored in prairie wetlands. Further, most models have not considered the influence of human-induced hydrologic changes, such as land use, that greatly influence quantity of surface water inputs and, ultimately, the rate that a wetland basin fills and spills. The goals of this study were to (1) develop and improve methodologies for estimating and spatially depicting wetland storage volumes and interceptions areas and (2) develop models and approaches for estimating/simulating the water storage capacity of potentially restorable and existing wetlands under various restoration, land use, and climatic scenarios. To address these goals, we developed models and approaches to spatially represent storage volumes and interception areas of existing and potentially restorable wetlands in the upper Mustinka subbasin within Grant County, Minn. We then developed and applied a model to simulate wetland water storage increases that would result from restoring 25 and 50 percent of the farmed and drained wetlands in the upper Mustinka subbasin. The model simulations were performed during the growing season (May-October) for relatively wet (1993; 0.79 m of precipitation) and dry (1987; 0.40 m of precipitation) years. Results from the simulations indicated that the 25 percent restoration scenario would increase water storage by 21-24 percent and that a 50 percent scenario would increase storage by 34-38 percent. Additionally, we estimated that wetlands in the subbasin have potential to store 11.57-20.98 percent of the total precipitation that fell over the entire subbasin area (52,758 ha). Our simulation results indicated that there is considerable potential to enhance water storage in the subbasin; however, evaluation and calibration of the model is necessary before simulation results can be applied to management and planning decisions. In this report we present guidance for the development and application of models (e.g., surface area-volume predictive models, hydrology simulation model) to simulate wetland water storage to provide a basis from which to understand and predict the effects of natural or human-induced hydrologic alterations. In developing these approaches, we tried to use simple and widely available input data to simulate wetland hydrology and predict wetland water storage for a specific precipitation event or a series of events. Further, the hydrology simulation model accounted for land use and soil type, which influence surface water inputs to wetlands. Although information presented in this report is specific to the Mustinka subbasin, the approaches

  5. How Faults Shape the Earth.

    ERIC Educational Resources Information Center

    Bykerk-Kauffman, Ann

    1992-01-01

    Presents fault activity with an emphasis on earthquakes and changes in continent shapes. Identifies three types of fault movement: normal, reverse, and strike faults. Discusses the seismic gap theory, plate tectonics, and the principle of superposition. Vignettes portray fault movement, and the locations of the San Andreas fault and epicenters of

  6. How Faults Shape the Earth.

    ERIC Educational Resources Information Center

    Bykerk-Kauffman, Ann

    1992-01-01

    Presents fault activity with an emphasis on earthquakes and changes in continent shapes. Identifies three types of fault movement: normal, reverse, and strike faults. Discusses the seismic gap theory, plate tectonics, and the principle of superposition. Vignettes portray fault movement, and the locations of the San Andreas fault and epicenters of…

  7. Fault detection and fault tolerance in robotics

    NASA Technical Reports Server (NTRS)

    Visinsky, Monica; Walker, Ian D.; Cavallaro, Joseph R.

    1992-01-01

    Robots are used in inaccessible or hazardous environments in order to alleviate some of the time, cost and risk involved in preparing men to endure these conditions. In order to perform their expected tasks, the robots are often quite complex, thus increasing their potential for failures. If men must be sent into these environments to repair each component failure in the robot, the advantages of using the robot are quickly lost. Fault tolerant robots are needed which can effectively cope with failures and continue their tasks until repairs can be realistically scheduled. Before fault tolerant capabilities can be created, methods of detecting and pinpointing failures must be perfected. This paper develops a basic fault tree analysis of a robot in order to obtain a better understanding of where failures can occur and how they contribute to other failures in the robot. The resulting failure flow chart can also be used to analyze the resiliency of the robot in the presence of specific faults. By simulating robot failures and fault detection schemes, the problems involved in detecting failures for robots are explored in more depth.

  8. Denali Fault: Gillette Pass

    View north of Denali fault trace at Gillette Pass. this view shows that the surface rupture reoccupies the previous fault scarp. Also the right-lateral offset of these stream gullies has developed since deglaciation in the last 10,000 years or so....

  9. Denali Fault: Gillette Pass

    View northward of mountain near Gillette Pass showing sackung features. Here the mountaintop moved downward like a keystone, producing an uphill-facing scarp. The main Denali fault trace is on the far side of the mountain and a small splay fault is out of view below the photo....

  10. Denali Fault: Alaska Pipeline

    View south along the Trans Alaska Pipeline in the zone where it was engineered for the Denali fault. The fault trace passes beneath the pipeline between the 2nd and 3rd slider supports at the far end of the zone. A large arc in the pipe can be seen in the pipe on the right, due to shortening of the ...

  11. Denali Fault: Susitna Glacier

    Helicopters and satellite phones were integral to the geologic field response. Here, Peter Haeussler is calling a seismologist to pass along the discovery of the Susitna Glacier thrust fault. View is to the north up the Susitna Glacier. The Denali fault trace lies in the background where the two lan...

  12. Fault geometry and cumulative offsets in the central Coast Ranges, California: Evidence for northward increasing slip along the San Gregorio-San Simeon-Hosgri fault

    USGS Publications Warehouse

    Langenheim, V.E.; Jachens, R.C.; Graymer, R.W.; Colgan, J.P.; Wentworth, C.M.; Stanley, R.G.

    2012-01-01

    Estimates of the dip, depth extent, and amount of cumulative displacement along the major faults in the central California Coast Ranges are controversial. We use detailed aeromagnetic data to estimate these parameters for the San Gregorio–San Simeon–Hosgri and other faults. The recently acquired aeromagnetic data provide an areally consistent data set that crosses the onshore-offshore transition without disruption, which is particularly important for the mostly offshore San Gregorio–San Simeon–Hosgri fault. Our modeling, constrained by exposed geology and in some cases, drill-hole and seismic-reflection data, indicates that the San Gregorio–San Simeon–Hosgri and Reliz-Rinconada faults dip steeply throughout the seismogenic crust. Deviations from steep dips may result from local fault interactions, transfer of slip between faults, or overprinting by transpression since the late Miocene. Given that such faults are consistent with predominantly strike-slip displacement, we correlate geophysical anomalies offset by these faults to estimate cumulative displacements. We find a northward increase in right-lateral displacement along the San Gregorio–San Simeon–Hosgri fault that is mimicked by Quaternary slip rates. Although overall slip rates have decreased over the lifetime of the fault, the pattern of slip has not changed. Northward increase in right-lateral displacement is balanced in part by slip added by faults, such as the Reliz-Rinconada, Oceanic–West Huasna, and (speculatively) Santa Ynez River faults to the east.

  13. Association of the 1886 Charleston, South Carolina, earthquake and seismicity near Summervile with a 12º bend in the East Coast fault system and triple-fault junctions

    USGS Publications Warehouse

    Marple, R.; Miller, R.

    2006-01-01

    Seismic-reflection data were integrated with other geophysical, geologic, and seismicity data to better determine the location and nature of buried faults in the Charleston, South Carolina, region. Our results indicate that the 1886 Charleston, South Carolina, earthquake and seismicity near Summerville are related to local stresses caused by a 12?? bend in the East Coast fault system (ECFS) and two triple-fault junctions. One triple junction is formed by the intersection of the northwest-trending Ashley River fault with the two segments of the ECFS north and south of the bend. The other triple junction is formed by the intersection of the northeast-trending Summerville fault and a newly discovered northwest-trending Berkeley fault with the ECFS about 10 km north of the bend. The Summerville fault is a northwest-dipping border fault of the Triassic-age Jedburg basin that is undergoing reverse-style reactivation. This reverse-style reactivation is unusual because the Summerville fault parallels the regional stress field axis, suggesting that the reactivation is from stresses applied by dextral motion on the ECFS. The southwest-dip and reverse-type motion of the Berkeley fault are interpreted from seismicity data and a seismic-reflection profile in the western part of the study area. Our results also indicate that the East Coast fault system is a Paleozoic basement fault and that its reactivation since early Mesozoic time has fractured through the overlying allochthonous terranes.

  14. Solar system fault detection

    DOEpatents

    Farrington, R.B.; Pruett, J.C. Jr.

    1984-05-14

    A fault detecting apparatus and method are provided for use with an active solar system. The apparatus provides an indication as to whether one or more predetermined faults have occurred in the solar system. The apparatus includes a plurality of sensors, each sensor being used in determining whether a predetermined condition is present. The outputs of the sensors are combined in a pre-established manner in accordance with the kind of predetermined faults to be detected. Indicators communicate with the outputs generated by combining the sensor outputs to give the user of the solar system and the apparatus an indication as to whether a predetermined fault has occurred. Upon detection and indication of any predetermined fault, the user can take appropriate corrective action so that the overall reliability and efficiency of the active solar system are increased.

  15. Solar system fault detection

    DOEpatents

    Farrington, Robert B.; Pruett, Jr., James C.

    1986-01-01

    A fault detecting apparatus and method are provided for use with an active solar system. The apparatus provides an indication as to whether one or more predetermined faults have occurred in the solar system. The apparatus includes a plurality of sensors, each sensor being used in determining whether a predetermined condition is present. The outputs of the sensors are combined in a pre-established manner in accordance with the kind of predetermined faults to be detected. Indicators communicate with the outputs generated by combining the sensor outputs to give the user of the solar system and the apparatus an indication as to whether a predetermined fault has occurred. Upon detection and indication of any predetermined fault, the user can take appropriate corrective action so that the overall reliability and efficiency of the active solar system are increased.

  16. Complex Rift-Parallel, Strike-Slip Faulting in Iceland: Kinematic Analysis of the Gljúfurá Fault Zone

    NASA Astrophysics Data System (ADS)

    Nanfito, A.; Karson, J. A.

    2009-12-01

    The N-S striking Gljúfurá Fault Zone is an anomalous, dextral, strike-slip fault cutting Tertiary basaltic lavas in west-central Iceland. The fault zone is nearly parallel to structures formed at extinct spreading centers that were active from ~15 to 7 Ma ago in this region, suggesting ridge-parallel strike-slip faulting. The fault zone is well exposed in a river gorge for ~2 km along a well-defined regional lineament. The combined damage zone and fault core are about 50 m wide revealing an especially intense and complex style of deformation compared to other Icelandic fault zones. Basaltic lava flows on either side of the fault zone are cut by numerous closely spaced (10s of cm to m) Riedel shear fractures that grade into a fault core of progressively more intensely fractured lava and strongly altered and mineralized fault breccias, cataclasite and fault gouge. Riedel shears are frequently rotated or bend into the main fault zone. Distinctive bands of fault breccia derived from lava flow interiors, flow tops and dike rock are mapped for tens of meters along strike and reach thicknesses of several meters wide. Breccias contain angular basaltic fragments that range from few meters to millimeters. Fault breccias are typically clast supported with a matix of finely comminuted basalt clasts to clay gouge. 'Jigsaw' breccias are supported by a calcite matrix. Discrete faults and shear fractures show dominantly gently plunging slickenlines and abundant kinematic indicators showing dextral>normal oblique slip. Zeolite and calcite veins show multiple episodes of extension. Local left steps in fault zone are marked by extensional duplex structures with vertical separations of tens of meters bounded by major strike-slip fault strands. The overall architecture of the fault zone in interpreted as an exhumed flower structure. Numerous deformed and undeformed basaltic dikes sub-parallel the deformation structures, suggesting synkinematic intrusion. Some dikes deviate from the strike of the fault zone and cut across the deformation fabrics. Although no features could be correlated across the fault zone to constrain the lateral displacement, empirical gouge thickness/displacement scaling relationships suggest at least several kilometers of slip. Previous studies interpreted the Gljúfurá Fault Zone was one of a family of parallel, strike-slip “bookshelf” faults associated with a transform fault zone linking two now-extinct rifts. Unlike the well-known rift-parallel, strike-slip faults of the South Iceland Seismic Zone and the Tjornes Fracture Zone, the Gljúfurá Fault Zone appears to be an isolated structure with substantially larger displacement that is discordant with surrounding basement lineaments. Major strike-slip faults of this kind can provide important clues in the reconstruction of ridge-hot spot interactions in Iceland.

  17. Fault detection and isolation

    NASA Technical Reports Server (NTRS)

    Bernath, Greg

    1994-01-01

    In order for a current satellite-based navigation system (such as the Global Positioning System, GPS) to meet integrity requirements, there must be a way of detecting erroneous measurements, without help from outside the system. This process is called Fault Detection and Isolation (FDI). Fault detection requires at least one redundant measurement, and can be done with a parity space algorithm. The best way around the fault isolation problem is not necessarily isolating the bad measurement, but finding a new combination of measurements which excludes it.

  18. Palaeoseismology of the L'Aquila faults (central Italy, 2009, Mw 6.3 earthquake): implications for active fault linkage

    NASA Astrophysics Data System (ADS)

    Galli, Paolo A. C.; Giaccio, Biagio; Messina, Paolo; Peronace, Edoardo; Zuppi, Giovanni Maria

    2011-12-01

    Urgent urban-planning problems related to the 2009 April, Mw 6.3, L'Aquila earthquake prompted immediate excavation of palaeoseismological trenches across the active faults bordering the Aterno river valley; namely, the Mt. Marine, Mt. Pettino and Paganica faults. Cross-cutting correlations amongst existing and new trenches that were strengthened by radiocarbon ages and archaeological constraints show unambiguously that these three investigated structures have been active since the Last Glacial Maximum period, as seen by the metric offset that affected the whole slope/alluvial sedimentary succession up to the historical deposits. Moreover, in agreement with both 18th century accounts and previous palaeoseismological data, we can affirm now that these faults were responsible for the catastrophic 1703 February 2, earthquake (Mw 6.7). The data indicate that the Paganica-San Demetrio fault system has ruptured in the past both together with the conterminous Mt. Pettino-Mt. Marine fault system, along more than 30 km and causing an Mw 6.7 earthquake, and on its own, along ca. 19 km, as in the recent 2009 event and in the similar 1461 AD event. This behaviour of the L'Aquila faults has important implications in terms of seismic hazard assessment, while it also casts new light on the ongoing fault linkage processes amongst these L'Aquila faults.

  19. Spatiotemporal Patterns of Fault Slip Rates Across the Central Sierra Nevada Frontal Fault Zone

    NASA Astrophysics Data System (ADS)

    Rood, D. H.; Burbank, D.; Finkel, R. C.

    2010-12-01

    We examine patterns in fault slip rates through time and space across the transition from the Sierra Nevada to the Eastern California Shear Zone-Walker Lane belt. At each of four sites along the eastern Sierra Nevada frontal fault zone between 38-39° N latitude, geomorphic markers, such as glacial moraines and outwash terraces, are displaced by a suite of range-front normal faults. Using geomorphic mapping, surveying, and Be-10 surface exposure dating, we define mean fault slip rates, and by utilizing markers of different ages (generally, ~20 ka and ~150 ka), we examine rates through time and interactions among multiple faults over 10-100 ky timescales. At each site for which data are available for the last ~150 ky, mean slip rates across the Sierra Nevada frontal fault zone have probably not varied by more than a factor of two over time spans equal to half of the total time interval (~20 ky and ~150 ky timescales): 0.3 ± 0.1 mm/yr (mode and 95% CI) at both Buckeye Creek in the Bridgeport basin and Sonora Junction; and 0.4 +0.3/-0.1 mm/yr along the West Fork of the Carson River at Woodfords. Our data permit that rates are relatively constant over the time scales examined. In contrast, slip rates are highly variable in space over the last ~20 ky. Slip rates decrease by a factor of 3-5 northward over a distance of ~20 km between the northern Mono Basin (1.3 +0.6/-0.3 mm/yr at Lundy Canyon site) and the Bridgeport Basin (0.3 ± 0.1 mm/yr). The 3-fold decrease in the slip rate on the Sierra Nevada frontal fault zone northward from Mono Basin reflects a change in the character of faulting north of the Mina Deflection as extension is transferred eastward onto normal faults between the Sierra Nevada and Walker Lane belt. A compilation of regional deformation rates reveal that the spatial pattern of extension rates changes along strike of the Eastern California Shear Zone-Walker Lane belt. South of the Mina Deflection, extension is accommodated within a diffuse zone of normal and oblique faults, with extension rates increasing northward on the Fish Lake Valley fault. Where faults of the Eastern California Shear Zone terminate northward into the Mina Deflection, extension rates increase northward along the Sierra Nevada frontal fault zone to ~0.7 mm/yr in northern Mono Basin. This spatial pattern suggests that extension is transferred from faults systems to the east (e.g. Fish Lake Valley fault) and localized on the Sierra Nevada frontal fault zone as Eastern California Shear Zone-Walker Lane belt faulting is transferred through the Mina Deflection.

  20. Measuring fault tolerance with the FTAPE fault injection tool

    NASA Technical Reports Server (NTRS)

    Tsai, Timothy K.; Iyer, Ravishankar K.

    1995-01-01

    This paper describes FTAPE (Fault Tolerance And Performance Evaluator), a tool that can be used to compare fault-tolerant computers. The major parts of the tool include a system-wide fault-injector, a workload generator, and a workload activity measurement tool. The workload creates high stress conditions on the machine. Using stress-based injection, the fault injector is able to utilize knowledge of the workload activity to ensure a high level of fault propagation. The errors/fault ratio, performance degradation, and number of system crashes are presented as measures of fault tolerance.

  1. PCB cleanup battle wages on in the Hudson River Valley

    SciTech Connect

    Nichols, A.B.

    1990-07-01

    The Hudson River between Troy, NY and Fort Edward, NY has sediments contaminated with polychlorobiphenyls (PCBs). The author discusses the legal red tape and public opinion problems associated with the clean up of this river.

  2. How do we identify big rivers? And how big is big?

    NASA Astrophysics Data System (ADS)

    Miall, Andrew D.

    2006-04-01

    "Big rivers" are the trunk rivers that carry the water and sediment load from major orogens, or that drain large areas of a continent. Identifying such rivers in the ancient record is a challenge. Some guidance may be provided by tectonic setting and sedimentological evidence, including the scale of architectural elements, and clues from provenance studies, but such data are not infallible guides to river magnitude. The scale of depositional elements is the most obvious clue to channel size, but evidence is typically sparse and inadequate, and may be misleading. For example, thick fining-upward successions may be tectonic cyclothems. Two examples of the analysis of large ancient river systems are discussed here in order to highlight problems of methodology and interpretation. The Hawkesbury Sandstone (Triassic) of the Sydney Basin, Australia, is commonly cited as the deposit of a large river, on the basis of abundant very large-scale crossbedding. An examination of very large outcrops of this unit, including a coastal cliff section 6 km long near Sydney, showed that even with 100% exposure there are ambiguities in the determination of channel scale. It was concluded in this case that the channel dimensions of the Hawkesbury rivers were about half the size of the modern Brahmaputra River. The tectonic setting of a major ancient fluvial system is commonly not a useful clue to river scale. The Hawkesbury Sandstone is a system draining transversely from a cratonic source into a foreland basin, whereas most large rivers in foreland basins flow axially and are derived mainly from the orogenic uplifts (e.g., the large tidally influenced rivers of the Athabasca Oil Sands, Alberta). Epeirogenic tilting of a continent by the dynamic topography process may generate drainages in unexpected directions. For example, analyses of detrital zircons in Upper Paleozoic-Mesozoic nonmarine successions in the SW United States suggests significant derivation from the Appalachian orogen. Many large rivers in SE Asia flow along structural trends generated during the Himalayan orogeny (e.g., Brahmaputra/Jamuna, Irrawaddy, Mekong, Red), but evidence for large channel systems is not always present where it might be expected. For example, in the Gulf of Thailand, up to 8 km of Cenozoic nonmarine sediments have been recorded in fault-bounded basins, but seismic time-slice images of the Pliocene-Holocene section indicate rivers of modest dimensions. The existing major trunk river, the Chao Phraya, which empties into the gulf at Bangkok, may be but a remnant of the Mekong, which was tectonically diverted to its present course at some point during the late Cenozoic.

  3. The Dead Sea Fault and Its Effect on Civilization

    NASA Astrophysics Data System (ADS)

    Ben-Avraham, Zvi; Lazar, Michael; Schattner, Uri; Marco, Shmuel

    The Dead Sea fault (DSF) is the most impressive tectonic feature in the Middle East. It is a plate boundary, which transfers sea floor spreading in the Red Sea to the Taurus collision zone in Turkey. The DSF has influenced many aspects of this region, including seismicity and ground water availability. It may have even affected the course of human evolution. Numerous geophysical and geological studies of the Dead Sea fault provide insight into its structure and evolution. Crustal structure studies have shown that the crust at the fault zone is slightly thinner than that of the regions west and east of it. A transition zone between the lower crust and the Moho under the fault was mapped.

  4. Fault zone structure of the Wildcat fault in Berkeley, California - Field survey and fault model test -

    NASA Astrophysics Data System (ADS)

    Ueta, K.; Onishi, C. T.; Karasaki, K.; Tanaka, S.; Hamada, T.; Sasaki, T.; Ito, H.; Tsukuda, K.; Ichikawa, K.; Goto, J.; Moriya, T.

    2010-12-01

    In order to develop hydrologic characterization technology of fault zones, it is desirable to clarify the relationship between the geologic structure and hydrologic properties of fault zones. To this end, we are performing surface-based geologic and trench investigations, geophysical surveys and borehole-based hydrologic investigations along the Wildcat fault in Berkeley,California to investigate the effect of fault zone structure on regional hydrology. The present paper outlines the fault zone structure of the Wildcat fault in Berkeley on the basis of results from trench excavation surveys. The approximately 20 - 25 km long Wildcat fault is located within the Berkeley Hills and extends northwest-southeast from Richmond to Oakland, subparallel to the Hayward fault. The Wildcat fault, which is a predominantly right-lateral strike-slip fault, steps right in a releasing bend at the Berkeley Hills region. A total of five trenches have been excavated across the fault to investigate the deformation structure of the fault zone in the bedrock. Along the Wildcat fault, multiple fault surfaces are branched, bent, paralleled, forming a complicated shear zone. The shear zone is ~ 300 m in width, and the fault surfaces may be classified under the following two groups: 1) Fault surfaces offsetting middle Miocene Claremont Chert on the east against late Miocene Orinda formation and/or San Pablo Group on the west. These NNW-SSE trending fault surfaces dip 50 - 60 to the southwest. Along the fault surfaces, fault gouge of up to 1 cm wide and foliated cataclasite of up to 60 cm wide can be observed. S-C fabrics of the fault gouge and foliated cataclasite show normal right-slip shear sense. 2) Fault surfaces forming a positive flower structure in Claremont Chert. These NW-SE trending fault surfaces are sub-vertical or steeply dipping. Along the fault surfaces, fault gouge of up to 3 cm wide and foliated cataclasite of up to 200 cm wide can be observed. S-C fabrics of the fault gouge and foliated cataclasite show reverse right-slip shear sense. We are performing sandbox experiments to investigate the three-dimensional kinematic evolution of fault systems caused by oblique-slip motion. The geometry of the Wildcat fault in the Berkeley Hills region shows a strong resemblance to our sandbox experimental model. Based on these geological and experimental data, we inferred that the complicated fault systems were dominantly developed within the fault step and the tectonic regime switched from transpression to transtension during the middle to late Miocene along the Wildcat fault.

  5. Fault rupture segmentation

    NASA Astrophysics Data System (ADS)

    Cleveland, Kenneth Michael

    A critical foundation to earthquake study and hazard assessment is the understanding of controls on fault rupture, including segmentation. Key challenges to understanding fault rupture segmentation include, but are not limited to: What determines if a fault segment will rupture in a single great event or multiple moderate events? How is slip along a fault partitioned between seismic and seismic components? How does the seismicity of a fault segment evolve over time? How representative are past events for assessing future seismic hazards? In order to address the difficult questions regarding fault rupture segmentation, new methods must be developed that utilize the information available. Much of the research presented in this study focuses on the development of new methods for attacking the challenges of understanding fault rupture segmentation. Not only do these methods exploit a broader band of information within the waveform than has traditionally been used, but they also lend themselves to the inclusion of even more seismic phases providing deeper understandings. Additionally, these methods are designed to be fast and efficient with large datasets, allowing them to utilize the enormous volume of data available. Key findings from this body of work include demonstration that focus on fundamental earthquake properties on regional scales can provide general understanding of fault rupture segmentation. We present a more modern, waveform-based method that locates events using cross-correlation of the Rayleigh waves. Additionally, cross-correlation values can also be used to calculate precise earthquake magnitudes. Finally, insight regarding earthquake rupture directivity can be easily and quickly exploited using cross-correlation of surface waves.

  6. Fault lubrication during earthquakes.

    PubMed

    Di Toro, G; Han, R; Hirose, T; De Paola, N; Nielsen, S; Mizoguchi, K; Ferri, F; Cocco, M; Shimamoto, T

    2011-03-24

    The determination of rock friction at seismic slip rates (about 1 m s(-1)) is of paramount importance in earthquake mechanics, as fault friction controls the stress drop, the mechanical work and the frictional heat generated during slip. Given the difficulty in determining friction by seismological methods, elucidating constraints are derived from experimental studies. Here we review a large set of published and unpublished experiments (∼300) performed in rotary shear apparatus at slip rates of 0.1-2.6 m s(-1). The experiments indicate a significant decrease in friction (of up to one order of magnitude), which we term fault lubrication, both for cohesive (silicate-built, quartz-built and carbonate-built) rocks and non-cohesive rocks (clay-rich, anhydrite, gypsum and dolomite gouges) typical of crustal seismogenic sources. The available mechanical work and the associated temperature rise in the slipping zone trigger a number of physicochemical processes (gelification, decarbonation and dehydration reactions, melting and so on) whose products are responsible for fault lubrication. The similarity between (1) experimental and natural fault products and (2) mechanical work measures resulting from these laboratory experiments and seismological estimates suggests that it is reasonable to extrapolate experimental data to conditions typical of earthquake nucleation depths (7-15 km). It seems that faults are lubricated during earthquakes, irrespective of the fault rock composition and of the specific weakening mechanism involved. PMID:21430777

  7. Fault tolerant magnetic bearings

    SciTech Connect

    Maslen, E.H.; Sortore, C.K.; Gillies, G.T.; Williams, R.D.; Fedigan, S.J.; Aimone, R.J.

    1999-07-01

    A fault tolerant magnetic bearing system was developed and demonstrated on a large flexible-rotor test rig. The bearing system comprises a high speed, fault tolerant digital controller, three high capacity radial magnetic bearings, one thrust bearing, conventional variable reluctance position sensors, and an array of commercial switching amplifiers. Controller fault tolerance is achieved through a very high speed voting mechanism which implements triple modular redundancy with a powered spare CPU, thereby permitting failure of up to three CPU modules without system failure. Amplifier/cabling/coil fault tolerance is achieved by using a separate power amplifier for each bearing coil and permitting amplifier reconfiguration by the controller upon detection of faults. This allows hot replacement of failed amplifiers without any system degradation and without providing any excess amplifier kVA capacity over the nominal system requirement. Implemented on a large (2440 mm in length) flexible rotor, the system shows excellent rejection of faults including the failure of three CPUs as well as failure of two adjacent amplifiers (or cabling) controlling an entire stator quadrant.

  8. Questa Baseline and Pre-Mining Ground-Water Quality Investigation 15.-Methods of Phase II and III Well Installation and Development and Results of Well Logging, Hydraulic Testing, and Water-Level Measurements in the Red River Valley, New Mexico, 2002-04

    USGS Publications Warehouse

    Blanchard, Paul J.; Bartolino, James R.; Donohoe, Lisa C.; McAda, Douglas P.; Naus, Cheryl A.; Morin, Roger H.

    2007-01-01

    In April 2001, the U.S. Geological Survey and the New Mexico Environment Department began a cooperative study to infer the pre-mining ground-water chemistry at the Molycorp molybdenum mine site in the Red River Valley of north- central New Mexico. This report is one in a series of reports that can be used to determine pre-mining ground-water conditions at the mine site. Weathering of hydrothermally altered bedrock in the study area has resulted in steep, highly erosive, and sparsely vegetated scar areas that are clearly visible from the ground and in aerial photographs. Runoff from intense summer rainfall over tributary drainages containing scar areas can transport large quantities of sediment and form debris fans where these tributaries join the Red River. Twenty-nine observation wells were installed in three phases as part of this study in the Red River Valley and tributary drainages. Eight Phase II observation wells were drilled using an air-rotary/hammer rig. Three Phase II and 10 phase III small-diameter wells were installed using a direct-push rig. Lithologic logs were recorded for all eight Phase II drilled wells. Borehole geophysical logging (including natural gamma, induction, and single-detector neutron) was conducted in three Phase II wells. Aquifer tests conducted during 2003 to estimate the hydraulic properties of debris-flow and Red River alluvial deposits in and near Straight Creek included a flow-meter survey, slug tests, and a pumping test. Results of a flow-meter survey in well SC-7A indicated that about 77 percent of the water entered the well from a 10-foot-thick zone near the top of the screened interval and about 23 percent of the water entered the well from a 15-foot-thick zone near the bottom of the screened interval. Slug tests, performed in 11 wells during June 3-5, 2003, indicated that the mean and median estimated hydraulic conductivities for debris-flow deposits were 15.25 and 15.35 feet per day, respectively, for bedrock were 0.12 and 0.08 feet per day, respectively, and for mixed debris flow and Red River alluvium were 73-207 (estimated range) and 80 feet per day. In general, bedrock has the smallest hydraulic conductivity, debris-flow material has the next highest hydraulic conductivity, and mixed debris flow and Red River alluvium has the largest hydraulic conductivity. A pumping test conducted December 3-4, 2003, using well AWWT-1 as the pumped well, and wells AWWT-2, SC-5A, SC-5B, SC-7A, and SC-8A as observation wells, indicated estimated transmissivity of 12,000 to 34,000 feet squared per day and estimated hydraulic conductivity of 230 to 340 feet per day. Water-level measurements in wells SC-6A, SC-7A, SC-8A, and the Hottentot, Hansen, and La Bobita wells show that water levels typically rose rapidly during melting of the winter snowpack in the springtime and then generally declined during the rest of the year. The water-level rise in response to spring snowmelt occurred earlier and was smaller at larger distances from the Red River. Differences between the stage in the Red River and water levels in wells SC-8A and SC-9A, and the absence of water in well SC-9A at the time of well completion, indicate that the Red River has a poor hydraulic connection to the underlying ground-water system and the surface-water system is perched above the ground-water system at this site. Water levels in Phase III wells indicate that the Red River and the shallow ground-water system are connected hydraulically from near wells 4-1D and 4-1S downstream to near wells 2-1 and 2-2 but are poorly connected near the La Bobita well and well 1.

  9. Seismic site characterization for the Deep-Fault-Drilling-Project Alpine Fault

    NASA Astrophysics Data System (ADS)

    Glomb, Vera; Buske, Stefan; Kovacs, Adrienn; Gorman, Andrew

    2013-04-01

    The Alpine Fault in New Zealand (South Island) is one of the largest active plate-bounding continental fault zones on earth with earthquakes of magnitude 7.9 occuring every 200-400 years. Due to the surface exposure and the shallow depth of mechanical and chemical transitions it is a globally significant natural laboratory. Within the ICDP Deep-Fault-Drilling-Project Alpine Fault (DFDP-AF; https://wiki.gns.cri.nz/DFDP) a drill hole shall give insight into the geological structure of the fault zone and its evolution to understand the related deformation and earthquake processes. With the help of advanced seismic imaging techniques the shallow structure of the Alpine Fault is imaged to find the most suitable drill site location. A new seismic reflection profile has been acquired in 2011 by the WhataDUSIE project team consisting of partners from the University of Otago (New Zealand), TU Bergakademie Freiberg (Germany) and the University of Alberta (Canada). The reflection profile, located in the Whataroa river valley, has a total length of about 5 km. Up to 643 geophones with spacings between 4-8 m recorded the approximately 100 shot points along the profile line. Single shot gathers as well as preliminary imaging results will be presented. The high-quality data show various indicators of the Alpine Fault such as strong reflections and distorted first-arrival wavefields which are clearly visible already in single shot gathers. With the help of high resolution seismic images we can study the shallow structures of the subsurface thus gaining information about the location and dip of reflectors. Further detailed processing and intensive interpretative work will enable a seismic site characterization providing important information for the selection of the borehole location. Additionally the high resolution seismic images themselves allow a better understanding of the tectonic and geodynamic settings.

  10. INVASION DYNAMICS OF RED SHINERS (CYPRINELLA LUTRENSIS) IN SOUTHEASTERN STREAMS

    EPA Science Inventory

    Red shiners have invaded a range of North American ecosystems, including several southeastern U.S. river drainages. A principle consequence of these invasions is extirpation of native congeners, either through competition or hydridization. We are conducting research to identify...

  11. 6. WORKERS COLLECTING SAGO PONDWEED, RED TOP GRASS, LEAFY PONDWEED, ...

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

    6. WORKERS COLLECTING SAGO PONDWEED, RED TOP GRASS, LEAFY PONDWEED, WATER MILFOIL, AND OTHER AQUATIC PLANTS FOR TRANSPLANTING FROM A COULEE SIX MILES AWAY FROM THE REFUGE - Upper Souris National Wildlife Refuge Dams, Souris River Basin, Foxholm, Ward County, ND

  12. Fault Roughness Records Strength

    NASA Astrophysics Data System (ADS)

    Brodsky, E. E.; Candela, T.; Kirkpatrick, J. D.

    2014-12-01

    Fault roughness is commonly ~0.1-1% at the outcrop exposure scale. More mature faults are smoother than less mature ones, but the overall range of roughness is surprisingly limited which suggests dynamic control. In addition, the power spectra of many exposed fault surfaces follow a single power law over scales from millimeters to 10's of meters. This is another surprising observation as distinct structures such as slickenlines and mullions are clearly visible on the same surfaces at well-defined scales. We can reconcile both observations by suggesting that the roughness of fault surfaces is controlled by the maximum strain that can be supported elastically in the wallrock. If the fault surface topography requires more than 0.1-1% strain, it fails. Invoking wallrock strength explains two additional observations on the Corona Heights fault for which we have extensive roughness data. Firstly, the surface is isotropic below a scale of 30 microns and has grooves at larger scales. Samples from at least three other faults (Dixie Valley, Mount St. Helens and San Andreas) also are isotropic at scales below 10's of microns. If grooves can only persist when the walls of the grooves have a sufficiently low slope to maintain the shape, this scale of isotropy can be predicted based on the measured slip perpendicular roughness data. The observed 30 micron scale at Corona Heights is consistent with an elastic strain of 0.01 estimated from the observed slip perpendicular roughness with a Hurst exponent of 0.8. The second observation at Corona Heights is that slickenlines are not deflected around meter-scale mullions. Yielding of these mullions at centimeter to meter scale is predicted from the slip parallel roughness as measured here. The success of the strain criterion for Corona Heights supports it as the appropriate control on fault roughness. Micromechanically, the criterion implies that failure of the fault surface is a continual process during slip. Macroscopically, the fundamental nature of the control means that 0.1 to 1% roughness should be ubiquitous on faults and can generally be used for simulating ground motion. An important caveat is that the scale-dependence of strength may result in a difference in the yield criterion at large-scales. The commonly observed values of the Hurst exponent below 1 may capture this scale-dependence.

  13. Testing simple models of brittle normal faulting: slip rate, spacing, and segmentation

    NASA Astrophysics Data System (ADS)

    Connolly, J.; Dawers, N. H.

    2005-05-01

    Fault growth and evolution is a complex process, however any predictable pattern will yield important information for assessing seismic hazard and clues to what controls fault behavior. Models of slip rate variation along strike, spacing of active faults, and scaling of segment length are investigated using data from faults located within the parabola of seismicity around the Yellowstone hotspot. Based on displacement-length relations and segment size, Cowie and Roberts used fault geometry to estimate along-strike slip rate variation in their 2001 paper (JSG,23,1901-1915). Following their model, along-strike slip rate profiles were calculated for three active normal faults: the Beaverhead, Lemhi, and Lost River faults. Though the method yields estimated slip rates, the results roughly mirror along-strike variation in total displacement, because the three faults are similar in size and age. The profiles indicate that the Beaverhead is underdisplaced, i.e. having a low slip rate relative to its length. This suggests that segment linkage occurred later in the development of the Beaverhead than in the others. Cowie and Roberts also proposed a model for fault spacing based on initial fault length and spacing, and maximum length and spacing of fully developed fault systems. Fault spacing is important in determining incidence and magnitude of fault movement. If the distance between faults is too small, strain becomes localized along one while the other exhibits a decrease in seismicity until no activity occurs. In practice it is impossible to know if the distance between the largest faults represents maximum fault spacing, because the fault population is still active and evolving; thus, it is difficult to test or implement the method. A relationship was found among faults within the study area, where spacing of adjacent active faults is proportional to the sums of their lengths. It was also observed that average segment length increases with increasing total fault length. The implications of segment length scaling with fault length are that larger faults should have larger earthquakes and surface ruptures, assuming segment length represents characteristic rupture size, and that processes controlling fault length also control segment length. No clear relationship between segment size and seismogenic layer thickness is observed.

  14. Red River chloride remote sensing study

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Side looking radar, infrared thermal imagery and color photography, together with a few examples of black and white panoramic photos, are used to supplement information on the natural saline pollution problem that is hydrologically and geologically oriented. The study area was explored concurrently by ground methods and a reasonably good understanding of hydrogeological conditions has been achieved. Examples of the products acquired, their interpretation, and use techniques are included.

  15. Lake Clark fault, assessment of tectonic activity based on reconnaissance mapping of glacial deposits, northwestern Cook Inlet Alaska

    NASA Astrophysics Data System (ADS)

    Reger, R. D.; Koehler, R. D.

    2009-12-01

    The Lake Clark fault extends ~247 km from the vicinity of Lake Clark in the Alaska-Aleutian Range batholith northeastward to the Castle Mountain fault along the northern margin of Cook Inlet. Documented Tertiary deformation along the fault includes dextral offsets (5-26 km) and north-side-up reverse displacements (500-1,000 m). The fault is along strike with the Holocene-active Castle Mountain fault and adjacent to the active northern Cook Inlet fold belt. As part of the STATEMAP program, the State of Alaska has begun a 2-year geologic mapping project in the vicinity of the Lake Clark fault, including assessment of Quaternary fault activity and its role in accommodating deformation in the Aleutian forearc. Here we present preliminary Quaternary mapping and tectonic geomorphic observations aimed at assessing the fault activity. Between the Beluga and Chakachatna rivers, large lateral moraines of the late Wisconsinan Naptowne glaciation cross the fault and are not displaced. In the vicinity of Lone Ridge, the fault is expressed as a ~25-m southeast-facing scarp in bedrock associated with springs and vertically offset Stage 4 or 6 moraines. In the Chuitna River drainage basin beyond the Naptowne ice limit, the fault extends across a fairly flat plateau with drumlins and ice-stagnation deposits related to Stage 4 or 6 glaciation. There the fault is expressed by subtle vegetation and tonal lineaments on air photos; however, scarps and lateral offsets were not observed. Stream profiles perpendicular to the fault along the Chuitna River and Chuitna Creek have convex profiles that could be related to tectonic folding. Our observations indicate that this part of the Lake Clark fault may be Quaternary active, but has been relatively quiescent in the late Pleistocene. Thus, blind thrust faults associated with the northern Cook Inlet fold belt may accommodate the majority of the tectonic deformation in this part of the Aleutian forearc. This information is applicable to earthquake hazard assessments for the Cook Inlet region.

  16. Diagnosable systems for intermittent faults

    NASA Technical Reports Server (NTRS)

    Mallela, S.; Masson, G. M.

    1978-01-01

    The fault diagnosis capabilities of systems composed of interconnected units capable of testing each other are studied for the case of systems with intermittent faults. A central role is played by the concept of t(i)-fault diagnosability. A system is said to be t(i)-fault diagnosable when it is such that if no more than t(i) units are intermittently faulty then a fault-free unit will never be diagnosed as faulty and the diagnosis at any time is at worst incomplete. Necessary and sufficient conditions for t(i)-fault diagnosability are proved, and bounds for t(i) are established. The conditions are in general more restrictive than those for permanent-fault diagnosability. For intermittent faults there is only one testing strategy (repetitive testing), and consequently only one type of intermittent-fault diagnosable system.

  17. Seeing Red

    NASA Technical Reports Server (NTRS)

    2008-01-01

    This New Horizons image of Jupiter's volcanic moon Io was taken at 13:05 Universal Time during the spacecraft's Jupiter flyby on February 28, 2007. It shows the reddish color of the deposits from the giant volcanic eruption at the volcano Tvashtar, near the top of the sunlit crescent, as well as the bluish plume itself and the orange glow of the hot lava at its source. The relatively unprocessed image on the left provides the best view of the volcanic glow and the plume deposits, while the version on the right has been brightened to show the much fainter plume, and the Jupiter-lit night side of Io.

    New Horizons' color imaging of Io's sunlit side was generally overexposed because the spacecraft's color camera, the super-sensitive Multispectral Visible Imaging Camera (MVIC), was designed for the much dimmer illumination at Pluto. However, two of MVIC's four color filters, the blue and 'methane' filter (a special filter designed to map methane frost on the surface of Pluto at an infrared wavelength of 0.89 microns), are less sensitive than the others, and thus obtained some well-exposed views of the surface when illumination conditions were favorable. Because only two color filters are used, rather than the usual three, and because one filter uses infrared light, the color is only a rough approximation to what the human eye would see.

    The red color of the Tvashtar plume fallout is typical of Io's largest volcanic plumes, including the previous eruption of Tvashtar seen by the Galileo and Cassini spacecraft in 2000, and the long-lived Pele plume on the opposite side of Io. The color likely results from the creation of reddish three-atom and four-atom sulfur molecules (S3 and S4) from plume gases rich in two-atom sulfur molecules (S2 After a few months or years, the S3 and S4 molecules recombine into the more stable and familiar yellowish form of sulfur consisting of eight-atom molecules (S8), so these red deposits are only seen around recently-active Io volcanos. Though the plume deposits are red, the plume itself is blue, because it is composed of very tiny particles that preferentially scatter blue light, like smoke. Also faintly visible in the left image is the pale-colored Prometheus plume, almost on the edge of the disk on the equator at the 9 o'clock position.

    Io was 2.4 million kilometers from the spacecraft when the picture was taken, and the center of Io's disk is at 77 degrees West longitude, 5 degrees South latitude. The solar phase angle was 107 degrees.

  18. Validated Fault Tolerant Architectures for Space Station

    NASA Technical Reports Server (NTRS)

    Lala, Jaynarayan H.

    1990-01-01

    Viewgraphs on validated fault tolerant architectures for space station are presented. Topics covered include: fault tolerance approach; advanced information processing system (AIPS); and fault tolerant parallel processor (FTPP).

  19. ANALYSIS OF BANK STABILITY AND POTENTIAL LOADINGS FROM STREAMBANKS ALONG THE SOUTH BRANCH OF THE BUFFALO RIVER, MN

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The South Branch of the Buffalo River is part of the larger Red River Basin, MN. In 1996 the Minnesota Pollution Control Agency (MPCA) performed water quality assessments for selected rivers and lakes in the Red River Basin, with impairment of streams primarily being found to be caused by high level...

  20. Fluid transport by solitary waves along growing faults. A field example from the South Eugene Island Basin, Gulf of Mexico

    NASA Astrophysics Data System (ADS)

    Revil, A.; Cathles, L. M.

    2002-09-01

    The Red Fault system is one of the main growth faults found in the South Eugene Island Basin, a salt withdrawal minibasin located offshore Louisiana, in the Gulf of Mexico. This fault system corresponds to a lateral boundary between fluid overpressured compartments. In addition, there is a set of observations indicating that the Red Fault system exhibits rapid episodic migration of fluids. This fault represents an example of preferential pathway for the upward episodic migration of overpressured hydrocarbons from deep, heavily pressured, compartments on time scales of years. The migrations of fluids into active growing faults could take the form of propagating surges (solitary waves) that propagate upward along the fault planes in a wave-like manner at km/yr. Solitary waves represent a very efficient mechanism for the upward transport of fluids along growth faults in sedimentary basins generating its own permeability. In addition, this mechanism is compatible with the fact that the fault plane is observed to sustain a static pore fluid pressure difference between its two sides. The propagation of solitary waves in active growth faults appears as a fundamental mechanism to understand the nature of upward fast migration of fluids along active growth faults in compartimentalized sedimentary basins.

  1. Computer hardware fault administration

    DOEpatents

    Archer, Charles J.; Megerian, Mark G.; Ratterman, Joseph D.; Smith, Brian E.

    2010-09-14

    Computer hardware fault administration carried out in a parallel computer, where the parallel computer includes a plurality of compute nodes. The compute nodes are coupled for data communications by at least two independent data communications networks, where each data communications network includes data communications links connected to the compute nodes. Typical embodiments carry out hardware fault administration by identifying a location of a defective link in the first data communications network of the parallel computer and routing communications data around the defective link through the second data communications network of the parallel computer.

  2. Cable fault locator research

    NASA Astrophysics Data System (ADS)

    Cole, C. A.; Honey, S. K.; Petro, J. P.; Phillips, A. C.

    1982-07-01

    Cable fault location and the construction of four field test units are discussed. Swept frequency sounding of mine cables with RF signals was the technique most thoroughly investigated. The swept frequency technique is supplemented with a form of moving target indication to provide a method for locating the position of a technician along a cable and relative to a suspected fault. Separate, more limited investigations involved high voltage time domain reflectometry and acoustical probing of mine cables. Particular areas of research included microprocessor-based control of the swept frequency system, a microprocessor based fast Fourier transform for spectral analysis, and RF synthesizers.

  3. Fault tolerant linear actuator

    DOEpatents

    Tesar, Delbert

    2004-09-14

    In varying embodiments, the fault tolerant linear actuator of the present invention is a new and improved linear actuator with fault tolerance and positional control that may incorporate velocity summing, force summing, or a combination of the two. In one embodiment, the invention offers a velocity summing arrangement with a differential gear between two prime movers driving a cage, which then drives a linear spindle screw transmission. Other embodiments feature two prime movers driving separate linear spindle screw transmissions, one internal and one external, in a totally concentric and compact integrated module.

  4. DIFFERENTIAL FAULT SENSING CIRCUIT

    DOEpatents

    Roberts, J.H.

    1961-09-01

    A differential fault sensing circuit is designed for detecting arcing in high-voltage vacuum tubes arranged in parallel. A circuit is provided which senses differences in voltages appearing between corresponding elements likely to fault. Sensitivity of the circuit is adjusted to some level above which arcing will cause detectable differences in voltage. For particular corresponding elements, a group of pulse transformers are connected in parallel with diodes connected across the secondaries thereof so that only voltage excursions are transmitted to a thyratron which is biased to the sensitivity level mentioned.

  5. Fault terminations, Seminoe Mountains, Wyoming

    SciTech Connect

    Dominic, J.B.; McConnell, D.A. . Dept. of Geology)

    1992-01-01

    Two basement-involved faults terminate in folds in the Seminoe Mountains. Mesoscopic and macroscopic structures in sedimentary rocks provide clues to the interrelationship of faults and folds in this region, and on the linkage between faulting and folding in general. The Hurt Creek fault trends 320[degree] and has maximum separation of 1.5 km measured at the basement/cover contact. Separation on the fault decreases upsection to zero within the Jurassic Sundance Formation. Unfaulted rock units form an anticline around the fault tip. The complementary syncline is angular with planar limbs and a narrow hinge zone. The syncline axial trace intersects the fault in the footwall at the basement/cover cut-off. Map patterns are interpreted to show thickening of Mesozoic units adjacent to the syncline hinge. In contrast, extensional structures are common in the faulted anticline within the Permian Goose Egg and Triassic Chugwater Formations. A hanging wall splay fault loses separation into the Goose Egg formation which is thinned by 50% at the fault tip. Mesoscopic normal faults are oriented 320--340[degree] and have an average inclination of 75[degree] SW. Megaboudins of Chugwater are present in the footwall of the Hurt Creek fault, immediately adjacent to the fault trace. The Black Canyon fault transported Precambrian-Pennsylvanian rocks over Pennsylvanian Tensleep sandstone. This fault is layer-parallel at the top of the Tensleep and loses separation along strike into an unfaulted syncline in the Goose Egg Formation. Shortening in the pre-Permian units is accommodated by slip on the basement-involved Black Canyon fault. Equivalent shortening in Permian-Cretaceous units occurs on a system of thin-skinned'' thrust faults.

  6. Fault displacement hazard for strike-slip faults

    USGS Publications Warehouse

    Petersen, M.D.; Dawson, T.E.; Chen, R.; Cao, T.; Wills, C.J.; Schwartz, D.P.; Frankel, A.D.

    2011-01-01

    In this paper we present a methodology, data, and regression equations for calculating the fault rupture hazard at sites near steeply dipping, strike-slip faults. We collected and digitized on-fault and off-fault displacement data for 9 global strikeslip earthquakes ranging from moment magnitude M 6.5 to M 7.6 and supplemented these with displacements from 13 global earthquakes compiled byWesnousky (2008), who considers events up to M 7.9. Displacements on the primary fault fall off at the rupture ends and are often measured in meters, while displacements on secondary (offfault) or distributed faults may measure a few centimeters up to more than a meter and decay with distance from the rupture. Probability of earthquake rupture is less than 15% for cells 200 m??200 m and is less than 2% for 25 m??25 m cells at distances greater than 200mfrom the primary-fault rupture. Therefore, the hazard for off-fault ruptures is much lower than the hazard near the fault. Our data indicate that rupture displacements up to 35cm can be triggered on adjacent faults at distances out to 10kmor more from the primary-fault rupture. An example calculation shows that, for an active fault which has repeated large earthquakes every few hundred years, fault rupture hazard analysis should be an important consideration in the design of structures or lifelines that are located near the principal fault, within about 150 m of well-mapped active faults with a simple trace and within 300 m of faults with poorly defined or complex traces.

  7. Late Quaternary faulting and historic seismicity in the western Lake Mead area, Nevada, Arizona and California

    SciTech Connect

    Anderson, L.W.; O'Connel, D.R. )

    1993-04-01

    As part of a regional seismic hazard study for Reclamation dams on the northern lower Colorado River, the age and distribution of known and suspected late Quaternary faults were investigated and historic seismicity was analyzed for the western Lake Mead area. Late Quaternary faults in the area consist of the Mead Slope, Black Hills, Frenchman Mountain, and California Wash faults. Geologic mapping and scarp profiles indicate that of these late Quaternary faults, the Black Hills fault displays evidence for the youngest (probably mid-Holocene) surface faulting. No information about the ages of older events was obtained for any of the faults; however, the ages of the most recent surface-rupturing events for individual faults suggest recurrence intervals of tens of thousands of years for specific faults and regional recurrence rates of several thousand years for M[sub 3] [>=] 6 1/2 events. Since 1936 when Hoover Dam was completed and the initial filling of Lake Mead began, the Boulder Basin area, the largest and deepest part of Lake Mead, has experienced abundant seismic activity that includes some of the largest historic earthquakes in southern Nevada (at least 21 M 4 events and one M 5). Based on earthquake locations from early networks (1937--1950) and those from temporary networks operating in 1975--1976 and 1988, earthquakes are clearly associated with the northeast-striking Mead Slope and Black Hills faults; one of the few associations of seismicity with late Quaternary faults in the Basin and Range. However, earthquakes also appear to be associated with the Fortification fault, a north-striking fault with no evidence of Quaternary surface faulting. Focal mechanisms for some of the 1975--1976 and 1988 events (all events M [<=] 3) suggest active strike-slip/oblique-slip motion on north-striking faults and normal/oblique-slip motion on northeast-striking structures.

  8. Fault tree models for fault tolerant hypercube multiprocessors

    NASA Technical Reports Server (NTRS)

    Boyd, Mark A.; Tuazon, Jezus O.

    1991-01-01

    Three candidate fault tolerant hypercube architectures are modeled, their reliability analyses are compared, and the resulting implications of these methods of incorporating fault tolerance into hypercube multiprocessors are discussed. In the course of performing the reliability analyses, the use of HARP and fault trees in modeling sequence dependent system behaviors is demonstrated.

  9. Source Fault and Rupture Process of the 2006 Yogyakarta Earthquake

    NASA Astrophysics Data System (ADS)

    Kawazoe, Y.; Koketsu, K.

    2010-12-01

    The Yogyakarta earthquake with a moment magnitude of 6.3 occurred in the central part of Java, Indonesia on 26 May 2006 at 22:54 UTC, causing severe damage to the densely populated area of the Yogyakarta region. About 6,000 people were killed, and 50,000 were injured. At first, the Opak River fault, located along the damage area, was thought to be a possible source fault of the event. However, the aftershock distribution suggests that the source fault is located 10 - 20 km east of the Opak River fault (Walter et al., 2007). This new fault was not known at that time, and its geometry and rupture process is little understood even now. Therefore, to overcome these difficulties, we performed teleseismic body-wave inversions. We chose the stations at epicentral distances between 30°and 100°. We retrieved 24 vertical components of broadband P-wave seismograms for these stations from the Data Management Center of IRIS. In order to perform an inversion for the rupture process, it is necessary to set up the source fault plane in advance. We first determined the focal mechanism using the inversion method of Kikuchi and Kanamori (1991). For calculating theoretical waveforms, we used near-source and near-receiver structures derived from CRUST 2.0. We obtained two different types of mechanism, that are left-lateral strike-slip faulting and reverse dip-slip faulting. Based on the obtained focal mechanisms and aftershock distribution, a fault plane is set up as follows: strike= 40°,dip= 85°,length =28km, width =20km , depth of rupture initiation point = 10km. We placed 7×5 grid points with a spacing of 4 km. We then inverted the waveforms for a spatio-temporal distribution of slip on this fault plane (Kikuchi and Kanamori,2003). In the inversion result, we obtained a total seismic moment Mo = 3.8×1013 Nm (Mw = 6.3), rupture front velocity = 2.5 km/s, rupture duration = 10 s, maximum slip = 0.34 m. The resultant slip distribution has two asperities (areas of large slip), which are located near the hypocenter and in the southwest. These results suggest the possibility of two different events. In the light of InSAR analysis, we will perform an inversion using two different fault segments. We will also perform a joint inversion of teleseismic body-wave and strong motion data.

  10. Fault-Tolerant Flight Computer

    NASA Technical Reports Server (NTRS)

    Chau, Savio

    1996-01-01

    In design concept for adaptive, fault-tolerant flight computer, upon detection of fault in either processor, surviving processor assumes responsibility for both equipment systems. Possible because of cross-strapping between processors, memories, and input/output units. Concept also applicable to other computing systems required to tolerate faults and in which partial loss of processing speed or functionality acceptable price to pay for continued operation in event of faults.

  11. Dynamic Fault Detection Chassis

    SciTech Connect

    Mize, Jeffery J

    2007-01-01

    Abstract The high frequency switching megawatt-class High Voltage Converter Modulator (HVCM) developed by Los Alamos National Laboratory for the Oak Ridge National Laboratory's Spallation Neutron Source (SNS) is now in operation. One of the major problems with the modulator systems is shoot-thru conditions that can occur in a IGBTs H-bridge topology resulting in large fault currents and device failure in a few microseconds. The Dynamic Fault Detection Chassis (DFDC) is a fault monitoring system; it monitors transformer flux saturation using a window comparator and dV/dt events on the cathode voltage caused by any abnormality such as capacitor breakdown, transformer primary turns shorts, or dielectric breakdown between the transformer primary and secondary. If faults are detected, the DFDC will inhibit the IGBT gate drives and shut the system down, significantly reducing the possibility of a shoot-thru condition or other equipment damaging events. In this paper, we will present system integration considerations, performance characteristics of the DFDC, and discuss its ability to significantly reduce costly down time for the entire facility.

  12. Row fault detection system

    DOEpatents

    Archer, Charles Jens; Pinnow, Kurt Walter; Ratterman, Joseph D.; Smith, Brian Edward

    2010-02-23

    An apparatus and program product check for nodal faults in a row of nodes by causing each node in the row to concurrently communicate with its adjacent neighbor nodes in the row. The communications are analyzed to determine a presence of a faulty node or connection.

  13. Row fault detection system

    DOEpatents

    Archer, Charles Jens; Pinnow, Kurt Walter; Ratterman, Joseph D.; Smith, Brian Edward

    2012-02-07

    An apparatus, program product and method check for nodal faults in a row of nodes by causing each node in the row to concurrently communicate with its adjacent neighbor nodes in the row. The communications are analyzed to determine a presence of a faulty node or connection.

  14. Row fault detection system

    SciTech Connect

    Archer, Charles Jens; Pinnow, Kurt Walter; Ratterman, Joseph D.; Smith, Brian Edward

    2008-10-14

    An apparatus, program product and method checks for nodal faults in a row of nodes by causing each node in the row to concurrently communicate with its adjacent neighbor nodes in the row. The communications are analyzed to determine a presence of a faulty node or connection.

  15. Anastomosing grabens, low-angle faults, and Tertiary thrust( ) faults, western Markagunt Plateau, southwestern Utah

    SciTech Connect

    Maldonado, F.; Sable, E.G. )

    1993-04-01

    A structurally complex terrane composed of grabens and horsts, low-angle faults, Tertiary thrust( ) faults, gravity-slide blocks, and debris deposits has been mapped along the western Markagunt Plateau, east of Parowan and Summit, southwestern Utah. This terrane, structurally situated within the transition between the Basin and Range and Colorado Plateau provinces, contains Tertiary volcanic and sedimentary and Cretaceous sedimentary rocks. The structures are mostly Miocene to Oligocene but some are Pleistocene. The oldest structure is the Red Hills low-angle shear zone, interpreted as a shallow structure that decoupled an upper plate composed of a Miocene-Oligocene volcanic ash-flow tuff and volcaniclastic succession from a lower plate of Tertiary sedimentary rocks. The period of deformation on the shear zone is bracketed from field relationships between 22.5 and 20 Ma. The graben-horst system trends northeast and formed after about 20 Ma (and probably much later) based on displacement of dated dikes and a laccolith. The central part of the system contains many grabens that merge toward its southerly end to become a single graben. Within these grabens, (1) older structures are preserved, (2) debris eroded from horst walls forms lobe-shaped deposits, (3) Pleistocene basaltic cinder cones have localized along graben-bounding faults, and (4) rock units are locally folded suggesting some component of lateral translation along graben-bounding faults. Megabreccia deposits and landslide debris are common. Megabreccia deposits are interpreted as gravity-slide blocks of Miocene-Oligocene( ) age resulting from formation of the Red Hills shear zone, although some may be related to volcanism, and still others to later deformation. The debris deposits are landslides of Pleistocene-Pliocene( ) age possibly caused by continued uplift of the Markagunt Plateau.

  16. Fault-Related Sanctuaries

    NASA Astrophysics Data System (ADS)

    Piccardi, L.

    2001-12-01

    Beyond the study of historical surface faulting events, this work investigates the possibility, in specific cases, of identifying pre-historical events whose memory survives in myths and legends. The myths of many famous sacred places of the ancient world contain relevant telluric references: "sacred" earthquakes, openings to the Underworld and/or chthonic dragons. Given the strong correspondence with local geological evidence, these myths may be considered as describing natural phenomena. It has been possible in this way to shed light on the geologic origin of famous myths (Piccardi, 1999, 2000 and 2001). Interdisciplinary researches reveal that the origin of several ancient sanctuaries may be linked in particular to peculiar geological phenomena observed on local active faults (like ground shaking and coseismic surface ruptures, gas and flames emissions, strong underground rumours). In many of these sanctuaries the sacred area is laid directly above the active fault. In a few cases, faulting has affected also the archaeological relics, right through the main temple (e.g. Delphi, Cnidus, Hierapolis of Phrygia). As such, the arrangement of the cult site and content of relative myths suggest that specific points along the trace of active faults have been noticed in the past and worshiped as special `sacred' places, most likely interpreted as Hades' Doors. The mythological stratification of most of these sanctuaries dates back to prehistory, and points to a common derivation from the cult of the Mother Goddess (the Lady of the Doors), which was largely widespread since at least 25000 BC. The cult itself was later reconverted into various different divinities, while the `sacred doors' of the Great Goddess and/or the dragons (offspring of Mother Earth and generally regarded as Keepers of the Doors) persisted in more recent mythologies. Piccardi L., 1999: The "Footprints" of the Archangel: Evidence of Early-Medieval Surface Faulting at Monte Sant'Angelo (Gargano, Italy). European Union of Geophysics Congress, Strasbourg, March 1999. Piccardi L., 2000: Active faulting at Delphi (Greece): seismotectonic remarks and a hypothesis for the geological environment of a myth. Geology, 28, 651-654. Piccardi L., 2001: Seismotectonic Origin of the Monster of Loch Ness. Earth System Processes, Joint Meeting of G.S.A. and G.S.L., Edinburgh, June 2001.

  17. Nucleation, linkage and active propagation of a segmented Quaternary normal-dextral fault: the Loma del Viento fault (Campo de Dalías, Eastern Betic Cordillera, SE Spain)

    NASA Astrophysics Data System (ADS)

    Pedrera, Antonio; Marín-Lechado, Carlos; Stich, Daniel; Ruiz-Constán, Ana; Galindo-Zaldívar, Jesús; Rey-Moral, Carmen; de Lis Mancilla, Flor

    2012-02-01

    Active faults from the Campo de Dalías (SE Betic Cordillera) allow us to constrain the deformation styles involved in the development of segmented oblique-slip faults. This sector constitutes the widest outcrop of Plio-Quaternary sediments in the northern boundary of the Alboran Sea. It has emerged since the Late Pliocene, and therefore provides recent deformation markers that are not disturbed by erosive processes. The faults started to grow during the Pleistocene, reactivating previous hybrid joints, with a normal-dextral slip. We present a detailed map of the largest fault in the area, the Loma del Viento fault, comprising six onshore segments. Based on field work and aerial photography, the distributions of the contiguous joints have been mapped, and the joints reactivated as faults are identified. Some of these fault segments are hard-linked, and fault slip enhances toward the linkage sectors between them with associated sedimentary depocenters. An electrical tomography profile reveals the wedge geometry of a unit of Pleistocene conglomerates and red silts that were coevally deposited during the fault movement. Long-term slip rate in the central part of the fault is estimated at 0.07 ± 0.03 mm/y. In addition, a seismic crisis nucleated close to the Loma del Viento fault during November 2010 was recorded. Moment tensor analysis of the two mainshocks (Mw 3.5 and 4.2) provides a focal solution indicating a N120°E striking right-lateral strike-slip fault. The corrugated morphology of the Loma del Viento fault may have influenced its seismic behavior. Some of the fault segments are oblique to the general motion of the fault. These oblique segments would provide higher resistance against the general fault motion and could lock the fault, leading to accumulate elastic energy.

  18. A Numerical Investigation of Drainage Network Evolution During Fault Interaction and Linkage

    NASA Astrophysics Data System (ADS)

    Cowie, P. A.; Naylor, M.; Whittaker, A.

    2003-12-01

    We have coupled together a numerical fault growth model and a surface process model (CASCADE; Braun and Sambridge, Basin Research, 9, 27-52, 1997) to study the way in which drainage basin geometry and river long profiles respond to the progressive formation and linkage of an underlying fault network. The numerical fault growth model simulates nucleation, propagation and displacement accumulation on a population of steeply dipping extensional faults. Elastic interaction between faults is included, resulting in significant displacement rate variations in space (along neighbouring fault segments) and through time. The most significant temporal variations in slip rate are those associated with fault linkage events in which the linking fault segments experience increased rates of slip while adjacent faults in foot-wall and hanging-wall areas become inactive. The size, elevation and lateral continuity of topographic uplifts (footwall highs) and depocentres (hanging-wall lows) vary through time as the faults grow and link. The faults appear as sub-vertical scarps that can grow in height and length through time. Fluvial erosion, diffusive hill-slope processes, landsliding, lake formation and sediment deposition are all included in the surface process model. Orographic effects are not considered. The tectonic model outputs maps of elevation change. These maps are input sequentially into the surface process model to drive tectonic elevation changes while erosion and deposition are ongoing. The spatial and temporal scales of the coupled model have been chosen to correspond with an area of active extensional faulting in Lazio-Abruzzo, Italy. Normal fault development in this area during the last 3 Myrs has resulted in interaction and incipient linkage between several fault segments that vary in length from 20 to 40 km, within a ~150 km long fault array. For this area we have river long profiles derived from a high-resolution DEM, and field measurements of river channels crossing faults that have experienced a temporal variation in throw rate. These data will be compared directly with outputs from the coupled numerical model.

  19. Earthquakes and fault creep on the northern San Andreas fault

    USGS Publications Warehouse

    Nason, R.

    1979-01-01

    At present there is an absence of both fault creep and small earthquakes on the northern San Andreas fault, which had a magnitude 8 earthquake with 5 m of slip in 1906. The fault has apparently been dormant after the 1906 earthquake. One possibility is that the fault is 'locked' in some way and only produces great earthquakes. An alternative possibility, presented here, is that the lack of current activity on the northern San Andreas fault is because of a lack of sufficient elastic strain after the 1906 earthquake. This is indicated by geodetic measurements at Fort Ross in 1874, 1906 (post-earthquake), and 1969, which show that the strain accumulation in 1969 (69 ?? 10-6 engineering strain) was only about one-third of the strain release (rebound) in the 1906 earthquake (200 ?? 10-6 engineering strain). The large difference in seismicity before and after 1906, with many strong local earthquakes from 1836 to 1906, but only a few strong earthquakes from 1906 to 1976, also indicates a difference of elastic strain. The geologic characteristics (serpentine, fault straightness) of most of the northern San Andreas fault are very similar to the characteristics of the fault south of Hollister, where fault creep is occurring. Thus, the current absence of fault creep on the northern fault segment is probably due to a lack of sufficient elastic strain at the present time. ?? 1979.

  20. An empirical comparison of software fault tolerance and fault elimination

    NASA Technical Reports Server (NTRS)

    Shimeall, Timothy J.; Leveson, Nancy G.

    1991-01-01

    Reliability is an important concern in the development of software for modern systems. Some researchers have hypothesized that particular fault-handling approaches or techniques are so effective that other approaches or techniques are superfluous. The authors have performed a study that compares two major approaches to the improvement of software, software fault elimination and software fault tolerance, by examination of the fault detection obtained by five techniques: run-time assertions, multi-version voting, functional testing augmented by structural testing, code reading by stepwise abstraction, and static data-flow analysis. This study has focused on characterizing the sets of faults detected by the techniques and on characterizing the relationships between these sets of faults. The results of the study show that none of the techniques studied is necessarily redundant to any combination of the others. Further results reveal strengths and weakness in the fault detection by the techniques studied and suggest directions for future research.

  1. The Wallula fault and tectonic framework of south-central Washington, as interpreted from magnetic and gravity anomalies

    SciTech Connect

    Blakely, Richard J.; Sherrod, Brian; Weaver, Craig; Wells, Ray E.; Rohay, Alan C.

    2013-11-13

    Magnetic and gravity data, collected in south-central Washington near the Yakima Fold and Thrust Belt (YFTB) are used to model upper crustal structure, the extent of the late Columbia River Basalt flow named the Ice Harbor member, the vertical conduits (dikes) that the Ice Harbor erupted from, and whether the dikes are offset or affected by faulting on the Wallula Fault zone.

  2. The application of Skylab imagery to analysis of fault tectonics and earthquake hazards in the Peninsular Ranges, southern California

    NASA Technical Reports Server (NTRS)

    Merifield, P. M. (Principal Investigator)

    1973-01-01

    The author has identified the following significant results. Frame 114 of the Salton Sea area was studied in all bands to analyze the appearance of important faults. These faults were also studied in the field as well as from aircraft and in aerial photography. The San Andreas/Banning and the Mission Creek faults can be traced across Coachella Valley even though they are buried by alluvium. The faults form ground water barriers and the near surface ground water on the northeast sides of the faults supports patches of vegetation (mesquite and palms) in an otherwise barren desert. These oases are best seen in band 3 (color IR). Otherwise, faults are best seen in band 4 (aerial color). Of the B and W bands, 5 (red) is best for delineating faults. Bands 1 and 2 are excessively grainy and the resolution is considerably inferior to the other bands.

  3. Wrench faulting in selected areas of Permian Basin

    SciTech Connect

    Bolden, G.P.

    1984-01-01

    Landsat and NASA High Altitude Special Mission Aircraft imagery have made it possible to define at least six separate lineament trends between the Amarillo-Wichita uplift (N62/sup 0/W) and the Texas lineament (N54/sup 0/W) that are 200 to 330 mi (320 to 530 km) long and oriented N54/sup 0/W to N62/sup 0/W. These long lineaments are thought to be P shears and are left-lateral wrench faults by definition. This left-lateral wrench fault system has been demonstrated at the Carta Valley fault zone. The Permian surface between Brown-Bassett and JM field of Terrell, Crockett, and Val Verde Counties along the Pecos River has a fracture system that is compatible with wrench faulting. In Garza and Borden Counties, the elements of left-lateral wrench faulting can be demonstrated from high altitude aircraft imagery and demonstrated on the surface and in the subsurface with seismic support. Surface lineaments are observed on Landsat imagery throughout the Permian basin and lead to the belief that the very long N54/sup 0/ to 62/sup 0/W lineaments are P shears. The set oriented N86/sup 0/ +/- E are the Riedel shears and the N36/sup 0/E are conjugate Riedel shears. These for high angle en echelon faults at the surface in Borden and Garza Counties, and with the surface alignments being documented on CDP seismic lines in the subsurface.

  4. Neotectonics in the southernmost part of Longitudinal Valley, eastern Taiwan and it's implications to the activity of Lichi Fault and Luyeh Fault

    NASA Astrophysics Data System (ADS)

    Chi, C.; Chen, W.

    2008-12-01

    Longitudinal Valley Fault (LVF) in eastern Taiwan is known as the suture of Eurasian Plate and Philippine Sea Plate. It is the major seismic zone in Taiwan, and has a high convergent rate up to 30 mm/yr. In the southernmost part of the Longitudinal Valley, the LVF system branches to two distinct faults Lichi Fault and Luyeh Fault, they offset and uplifted the Holocene terraces and may fracture in the 1951 earthquake series. For lack of dating and firsthand evidence, there is just a rough definition of the activity of them, and the ambiguous of the fault trace is also controversial for a long time. The main purpose of this study is to solve the question about the fault activity, and further, we want to suggest the subsurface structural model of this area. According to the terrace dating, the uplift rates we estimated are 17~20 mm/yr and 3 mm/yr of the hanging wall of the Lichi Fault and Luyeh Fault respectively. In addition, we estimate the uplift rate of the Central Range Fault (< 4.1 mm/yr) that bounded the west side of Longitudinal Valley based on the assumption of the balance between river incision, aggradation, and tectonic uplift. Based on the field observation and the trend of GPS velocity profile, we assume Lichi Fault and Luyeh Fault are totally creeping that we can serve the short-term GPS velocity as the long-term crust motion rate. Then we simply reverse the vertical and horizontal rate of crust motion to the fault plane, and infer that the dip angle of the Lichi Fault is 53° in the upper part and decline to 30° below 7 km and the Luyeh Fault is 17° in the shallow depth of the valley. Concluding the result of this study, we confirm that Lichi fault and Luyeh fault are active through Holocene and may behave as creeping faults. And the fault geometry we inferred is close to that inferred from the aftershock distribution of 2006 Mw 6.1 Taitung earthquake.

  5. Tectonic geomorphology and paleoseismology of strike-slip faults in Jamaica: Implications for distribution of strain and seismic hazard along the southern edge of the Gonave microplate

    NASA Astrophysics Data System (ADS)

    Koehler, R. D.; Mann, P.; Brown, L. A.

    2009-12-01

    The east-west, left lateral strike-slip fault system forming the southern edge of the Gonave microplate crosses the110-km-long and 70-km-wide island of Jamaica. GPS measurements in the northeastern Caribbean are supportive of the microplate interpretation and indicate that ~ half of the Caribbean-North America left-lateral plate motion (8-14 mm/yr) is carried by the Plantain Garden (PGFZ) and associated faults in Jamaica. We performed Neotectonic mapping of the Plantain Garden fault along the southern rangefront of the Blue Mountains and conducted a paleoseismic study of the fault at Morant River. Between Holland Bay and Morant River, the fault is characterized by a steep, faceted, linear mountain front, prominent linear valleys and depressions, shutter ridges, and springs. At the eastern end of the island, the PGFZ is characterized by a left-stepping fault geometry that includes a major, active hot spring. The river cut exposure at Morant River exposes a 1.5-m-wide, sub-vertical fault zone juxtaposing sheared alluvium and faulted Cretaceous basement rocks. This section is overlain by an, unfaulted 3-m-thick fluvial terrace inset into a late Pleistocene terrace that is culturally modified. Upward fault terminations indicate the occurrence of three paleoearthquakes that occurred prior to deposition of the flat lying inset terrace around 341-628 cal yr BP. At this time, our radiocarbon results suggest that we can rule out the PGFZ as the source of the 1907 Kingston earthquake 102 years ago, as well as, the 1692 event that destroyed Port Royal 317 years ago and produced a major landslide at Yallahs. Pending OSL ages will constrain the age of the penultimate and most recent ruptures. Gently to steeply dipping rocks as young as Pliocene exposed in roadcuts within the low coastal hills south of and parallel to the Plantain Garden fault may indicate active folding and blind thrust faulting. These structures are poorly characterized and may accommodate an unknown amount of oblique strain. Reconnaissance mapping was also performed along the South Coast fault in south-central Jamaica north of Portland Ridge, and along the Crawle River-Rio Minho fault near Frankfield in the Central Inlier. The absence of fault scarps or other tectonic geomorphic features across fluvial terraces of the Milk and Minho Rivers indicate that the South Coast fault has not been active in Holocene time. Left laterally offset streams, linear valleys, and saddles support active faulting along the east-west Crawle River-Rio Minho fault that is roughly collinear with the western extension of the Plantain Garden fault.

  6. Fault Scarp Offsets and Fault Population Analysis on Dione

    NASA Astrophysics Data System (ADS)

    Tarlow, S.; Collins, G. C.

    2010-12-01

    Cassini images of Dione show several fault zones cutting through the moon’s icy surface. We have measured the displacement and length of 271 faults, and estimated the strain occurring in 6 different fault zones. These measurements allow us to quantify the total amount of surface strain on Dione as well as constrain what processes might have caused these faults to form. Though we do not have detailed topography across fault scarps on Dione, we can use their projected size on the camera plane to estimate their heights, assuming a reasonable surface slope. Starting with high resolution images of Dione obtained by the Cassini ISS, we marked points at the top to the bottom of each fault scarp to measure the fault’s projected displacement and its orientation along strike. Line and sample information for the measurements were then processed through ISIS to derive latitude/longitude information and pixel dimensions. We then calculate the three dimensional orientation of a vector running from the bottom to the top of the fault scarp, assuming a 45 degree angle with respect to the surface, and project this vector onto the spacecraft camera plane. This projected vector gives us a correction factor to estimate the actual vertical displacement of the fault scarp. This process was repeated many times for each fault, to show variations of displacement along the length of the fault. To compare each fault to its neighbors and see how strain was accommodated across a population of faults, we divided the faults into fault zones, and created new coordinate systems oriented along the central axis of each fault zone. We could then quantify the amount of fault overlap and add the displacement of overlapping faults to estimate the amount of strain accommodated in each zone. Faults in the southern portion of Padua have a strain of 0.031(+/-) 0.0097, central Padua exhibits a strain of .032(+/-) 0.012, and faults in northern Padua have a strain of 0.025(+/-) 0.0080. The western faults of Eurotas have a strain of 0.031(+/-) 0.011, while the eastern faults have a strain of 0.037(+/-) 0.025. Lastly, Clusium has a strain of 0.10 (+/-) 0.029. We also calculated the ratio of maximum fault displacement vs. the length of the faults, and we found this ratio to be 0.019 when drawing a trend line through all the faults that were analyzed. D/L measurements performed on two faults on Europa using stereo topography showed a value of .021 (Nimmo and Schenk 2006), the only other icy satellite where this ratio has been measured. In contrast, faults on Earth has a D/L ratio of about .1 and Mars has a D/L Ratio of about .01 (Schultz et al. 2006).

  7. Abnormal fault-recovery characteristics of the fault-tolerant multiprocessor uncovered using a new fault-injection methodology

    NASA Astrophysics Data System (ADS)

    Padilla, Peter A.

    1991-03-01

    An investigation was made in AIRLAB of the fault handling performance of the Fault Tolerant MultiProcessor (FTMP). Fault handling errors detected during fault injection experiments were characterized. In these fault injection experiments, the FTMP disabled a working unit instead of the faulted unit once in every 500 faults, on the average. System design weaknesses allow active faults to exercise a part of the fault management software that handles Byzantine or lying faults. Byzantine faults behave such that the faulted unit points to a working unit as the source of errors. The design's problems involve: (1) the design and interface between the simplex error detection hardware and the error processing software, (2) the functional capabilities of the FTMP system bus, and (3) the communication requirements of a multiprocessor architecture. These weak areas in the FTMP's design increase the probability that, for any hardware fault, a good line replacement unit (LRU) is mistakenly disabled by the fault management software.

  8. Abnormal fault-recovery characteristics of the fault-tolerant multiprocessor uncovered using a new fault-injection methodology

    NASA Technical Reports Server (NTRS)

    Padilla, Peter A.

    1991-01-01

    An investigation was made in AIRLAB of the fault handling performance of the Fault Tolerant MultiProcessor (FTMP). Fault handling errors detected during fault injection experiments were characterized. In these fault injection experiments, the FTMP disabled a working unit instead of the faulted unit once in every 500 faults, on the average. System design weaknesses allow active faults to exercise a part of the fault management software that handles Byzantine or lying faults. Byzantine faults behave such that the faulted unit points to a working unit as the source of errors. The design's problems involve: (1) the design and interface between the simplex error detection hardware and the error processing software, (2) the functional capabilities of the FTMP system bus, and (3) the communication requirements of a multiprocessor architecture. These weak areas in the FTMP's design increase the probability that, for any hardware fault, a good line replacement unit (LRU) is mistakenly disabled by the fault management software.

  9. Holocene faulting on the Mission fault, northwest Montana

    SciTech Connect

    Ostenaa, D.A.; Klinger, R.E.; Levish, D.R. )

    1993-04-01

    South of Flathead Lake, fault scarps on late Quaternary surfaces are nearly continuous for 45 km along the western flank of the Mission Range. On late Pleistocene alpine lateral moraines, scarp heights reach a maximum of 17 m. Scarp heights on post glacial Lake Missoula surfaces range from 2.6--7.2 m and maximum scarp angles range from 10[degree]--24[degree]. The stratigraphy exposed in seven trenches across the fault demonstrates that the post glacial Lake Missoula scarps resulted from at least two surface-faulting events. Larger scarp heights on late Pleistocene moraines suggests a possible third event. This yields an estimated recurrence of 4--8 kyr. Analyses of scarp profiles show that the age of the most surface faulting is middle Holocene, consistent with stratigraphic evidence found in the trenches. Rupture length and displacement imply earthquake magnitudes of 7 to 7.5. Previous studies have not identified geologic evidence of late Quaternary surface faulting in the Rocky Mountain Trench or on faults north of the Lewis and Clark line despite abundant historic seismicity in the Flathead Lake area. In addition to the Mission fault, reconnaissance studies have located late Quaternary fault scarps along portions of faults bordering Jocko and Thompson Valleys. These are the first documented late Pleistocene/Holocene faults north of the Lewis and Clark line in Montana and should greatly revise estimates of earthquake hazards in this region.

  10. Late Cenozoic strike-slip faulting in the NE Mojave Block: Deformation at the southwest boundary of the Walker Lane belt

    SciTech Connect

    Schermer, E.R. . Geology Dept.)

    1993-04-01

    New structural and stratigraphy data from the NE Mojave Block (NEMB) establish the timing and style of Cenozoic deformation south of the Garlock fault and west of the Avawatz Mts. Unlike adjacent areas, most of the NEMB did not undergo early-mid Miocene extension. Major fault zones strike EW; offset markers and small-scale shear criteria indicate left-lateral strike slip with a small reverse component. Lateral offsets average ca. 1--6 km and vertical offset is locally >200m. Pre-Tertiary markers indicate minimum cumulative sinistral shear of ca. 15 km in the area between the Garlock and Coyote Lake faults. Tertiary strata are deformed together with the older rocks. Along the Ft. Irwin fault, alluvial fan deposits interpreted to be <11Ma appear to be displaced as much as Mesozoic igneous rocks. EW sinistral faults S. of the Garlock fault cut unconsolidated Quaternary deposits; geomorphologic features and trench exposures along segments of the McLean Lake fault and the Tiefort Mt. fault suggest Late Quaternary activity. The EW faults do not cut modern drainages and are not seismically active. NW-striking faults are largely absent within the NEMB; the largest faults bound the domain of EW-striking faults. Offset of Cretaceous and Miocene rocks suggests the W boundary (Goldstone Lake fault) has <2km right separation. Along the E boundary (Soda-Avawatz fault zone), the presence of distinctive clasts in mid-late Miocene conglomerates west of the Avawatz Mts. supports the suggestion of Brady (1984) of ca. 20 km dextral displacement. Other NW-striking faults are cut by EW faults, have unknown or minor dextral displacement (Desert King Spring Fault, Garlic Spring fault) or are low- to moderate-angle left-oblique thrust faults (Red Pass Lake fault zone).

  11. An experiment in software fault elimination and fault tolerance

    SciTech Connect

    Shimeall, T.J.

    1989-01-01

    Three primary approaches have been taken in developing methods to improve software reliability: fault avoidance, fault elimination and fault tolerance. This study investigates the error detection obtained by application of two of these approaches, fault tolerance and fault elimination, on a set of independently developed versions of a program. Different fault detection techniques following each approach are used to provide a broad exposure of each approach on the versions. The fault detection techniques chosen were multi-version voting, programmer-inserted run-time assertions, testing, code reading of uncommented code by stepwise abstraction and static data flow analysis. Voting and run-time assertions are most commonly associated with fault tolerance. Testing, code reading and static data flow analysis are most commonly associated with fault elimination. After application of the techniques following each approach, the errors detected and the circumstances of detection were analyzed as a means of characterizing the differences between the approaches. The results of this study provide insight on a series of research questions. The results demonstrate weaknesses in the fault tolerance approach and specifically in the multi-version voting method. In particular, the results demonstrate that voting of untested software may produce an insufficient improvement in the probability of producing a correct result to consider such use in systems where reliability is important. Voting is not to be a substitute for testing. Examination of the faults detected in this experiment show that the majority of faults were detected by only one technique. The results of this study suggest a series of questions for further research. For example, research is needed on how to broaden the classes of faults detected by each technique.

  12. Randomness fault detection system

    NASA Technical Reports Server (NTRS)

    Russell, B. Don (Inventor); Aucoin, B. Michael (Inventor); Benner, Carl L. (Inventor)

    1996-01-01

    A method and apparatus are provided for detecting a fault on a power line carrying a line parameter such as a load current. The apparatus monitors and analyzes the load current to obtain an energy value. The energy value is compared to a threshold value stored in a buffer. If the energy value is greater than the threshold value a counter is incremented. If the energy value is greater than a high value threshold or less than a low value threshold then a second counter is incremented. If the difference between two subsequent energy values is greater than a constant then a third counter is incremented. A fault signal is issued if the counter is greater than a counter limit value and either the second counter is greater than a second limit value or the third counter is greater than a third limit value.

  13. Managing Fault Management Development

    NASA Technical Reports Server (NTRS)

    McDougal, John M.

    2010-01-01

    As the complexity of space missions grows, development of Fault Management (FM) capabilities is an increasingly common driver for significant cost overruns late in the development cycle. FM issues and the resulting cost overruns are rarely caused by a lack of technology, but rather by a lack of planning and emphasis by project management. A recent NASA FM Workshop brought together FM practitioners from a broad spectrum of institutions, mission types, and functional roles to identify the drivers underlying FM overruns and recommend solutions. They identified a number of areas in which increased program and project management focus can be used to control FM development cost growth. These include up-front planning for FM as a distinct engineering discipline; managing different, conflicting, and changing institutional goals and risk postures; ensuring the necessary resources for a disciplined, coordinated approach to end-to-end fault management engineering; and monitoring FM coordination across all mission systems.

  14. Microtremors from the Reelfoot Fault

    NASA Astrophysics Data System (ADS)

    Bockholt, B.; Langston, C. A.; DeShon, H. R.

    2011-12-01

    A phased array of 19 broadband seismometers has been deployed since November 2009 in Mooring, TN, in order to re-observe microtremor activity in the New Madrid Seismic Zone. An unusual set of high velocity signals identified in this region on an active source experiment in 2006 were interpreted as non-volcanic tremor. We search for signals with high phase velocity (3-25 km/s) in the 8-15 Hz frequency band that originate directly below the array, possibly on the Reelfoot thrust fault, similar to the original signals seen in the active source survey. We are interested in arrivals in the vertical components since there was no noticeable horizontal displacement in the original 2006 data set. In order to search this large dataset quickly and efficiently, an auto-detection algorithm has been written that filters the data and uses a broadband frequency/wavenumber array analysis to choose the energy peak with a certain slowness and azimuth window. When implemented, a weeks worth of data can be analyzed overnight. We have searched 6 months of data and have detected hundreds of candidate signals. These signals are only detectable on the vertical components of the array; no corresponding arrivals can be found within horizontal components. Detections are very different from local earthquakes and teleseismic events in both frequency content and duration. They are easily distinguishable from local well pumping, road and river traffic because they lack periodicity. These microtremor signals can occur as short burst of P-wave energy from a single to multiple arrivals over a duration of 2 minutes. The source of these arrivals is not yet known, but the high apparent phase velocity would imply that they originate from directly below the array. We are continuing to assemble a catalog of these mystery signals and are searching for patterns or trends to gain insight into their source processes. Our results will determine whether or not these signals are related to non-volcanic tremor noted in other fault settings or if they are a manifestation of another unknown process in the New Madrid Seismic Zone.

  15. Fault tolerant control laws

    NASA Technical Reports Server (NTRS)

    Ly, U. L.; Ho, J. K.

    1986-01-01

    A systematic procedure for the synthesis of fault tolerant control laws to actuator failure has been presented. Two design methods were used to synthesize fault tolerant controllers: the conventional LQ design method and a direct feedback controller design method SANDY. The latter method is used primarily to streamline the full-state Q feedback design into a practical implementable output feedback controller structure. To achieve robustness to control actuator failure, the redundant surfaces are properly balanced according to their control effectiveness. A simple gain schedule based on the landing gear up/down logic involving only three gains was developed to handle three design flight conditions: Mach .25 and Mach .60 at 5000 ft and Mach .90 at 20,000 ft. The fault tolerant control law developed in this study provides good stability augmentation and performance for the relaxed static stability aircraft. The augmented aircraft responses are found to be invariant to the presence of a failure. Furthermore, single-loop stability margins of +6 dB in gain and +30 deg in phase were achieved along with -40 dB/decade rolloff at high frequency.

  16. Logs of Paleoseismic Excavations Across the Central Range Fault, Trinidad

    USGS Publications Warehouse

    Crosby, Christopher J.; Prentice, Carol S.; Weber, John; Ragona, Daniel

    2009-01-01

    This publication makes available maps and trench logs associated with studies of the Central Range Fault, part of the South American-Caribbean plate boundary in Trinidad. Our studies were conducted in 2001 and 2002. We mapped geomorphic features indicative of active faulting along the right-lateral, Central Range Fault, part of the South American-Caribbean plate boundary in Trinidad. We excavated trenches at two sites, the Samlalsingh and Tabaquite sites. At the Samlalsingh site, sediments deposited after the most recent fault movement bury the fault, and the exact location of the fault was unknown until we exposed it in our excavations. At this site, we excavated a total of eleven trenches, six of which exposed the fault. The trenches exposed fluvial sediments deposited over a strath terrace developed on Miocene bedrock units. We cleaned the walls of the excavations, gridded the walls with either 1 m X 1 m or 1 m X 0.5 m nail and string grid, and logged the walls in detail at a scale of 1:20. Additionally, we described the different sedimentary units in the field, incorporating these descriptions into our trench logs. We mapped the locations of the trenches using a tape and compass. Our field logs were scanned, and unit contacts were traced in Adobe Illustrator. The final drafted logs of all the trenches are presented here, along with photographs showing important relations among faults and Holocene sedimentary deposits. Logs of south walls were reversed in Illustrator, so that all logs are drafted with the view direction to the north. We collected samples of various materials exposed in the trench walls, including charcoal samples for radiocarbon dating from both faulted and unfaulted deposits. The locations of all samples collected are shown on the logs. The ages of seventeen of the charcoal samples submitted for radiocarbon analysis at the University of Arizona Accelerator Mass Spectrometry Laboratory in Tucson, Ariz., are given in Table 1. Samples found in Table 1 are shown in red on the trench logs. All radiocarbon ages are calibrated and given with 2 standard deviation age ranges. Our studies suggest that the Central Range Fault is a Holocene fault capable of producing damaging earthquakes in Trinidad

  17. Lidar-Based Mapping of Late Quaternary Faulting Along the Grizzly Valley Fault, Walker Lane Seismic Belt, California

    NASA Astrophysics Data System (ADS)

    Hitchcock, C. S.; Hoirup, D. F.; Barry, G.; Pearce, J.; Glick, F.

    2012-12-01

    The Grizzly Valley fault (GVF) is located within the northern Walker Lane, a zone of right-lateral shear between the Sierra Nevada and the Basin and Range in Plumas County. The GVF extends southeasterly from near Mt. Ingalls along the eastern side of Lake Davis. It may partially connect with the Hot Creek fault within Sierra Valley and extend south to Loyalton with an overall approximate length of 50 km. Comparison of high-resolution topography developed from LiDAR data with published bedrock geologic mapping documents the presence of geomorphic features that provide information on fault activity of the GVF. Field mapping verified tectonically deformed and offset late Quaternary surfaces identified on bare-earth LiDAR imagery across the GVF within glacial deposits on the eastern margin of Lake Davis, and alluvial deposits in Sierra Valley. Along the GVF, conspicuous geomorphic and hydrologic features include scarps in alluvial surfaces, elongated depressions aligned with adjacent linear escarpments, truncated bedrock spurs, closed depressions, linear swales, right-lateral deflections of creeks and river courses, and shutter ridges, as well as springs and linear seeps consistent with right-lateral strike-slip faulting. The discontinuous nature of observed fault traces combined with the apparent down-to-the-west offset of alluvial surfaces at the southern and northern ends of the eastern margin of Lake Davis are consistent with a broad bend or step over in the fault. Scarp profiles of apparently faulted surfaces extracted from LiDAR data document vertical offsets of up to 14 m. Our study suggest that the GVF is an oblique, right-lateral fault that has been active in the late Quaternary. This study complements on-going investigations by DWR to assess the impact of seismic hazards on State Water Project infrastructure.

  18. Seismic Hazard and Fault Length

    NASA Astrophysics Data System (ADS)

    Black, N. M.; Jackson, D. D.; Mualchin, L.

    2005-12-01

    If mx is the largest earthquake magnitude that can occur on a fault, then what is mp, the largest magnitude that should be expected during the planned lifetime of a particular structure? Most approaches to these questions rely on an estimate of the Maximum Credible Earthquake, obtained by regression (e.g. Wells and Coppersmith, 1994) of fault length (or area) and magnitude. Our work differs in two ways. First, we modify the traditional approach to measuring fault length, to allow for hidden fault complexity and multi-fault rupture. Second, we use a magnitude-frequency relationship to calculate the largest magnitude expected to occur within a given time interval. Often fault length is poorly defined and multiple faults rupture together in a single event. Therefore, we need to expand the definition of a mapped fault length to obtain a more accurate estimate of the maximum magnitude. In previous work, we compared fault length vs. rupture length for post-1975 earthquakes in Southern California. In this study, we found that mapped fault length and rupture length are often unequal, and in several cases rupture broke beyond the previously mapped fault traces. To expand the geologic definition of fault length we outlined several guidelines: 1) if a fault truncates at young Quaternary alluvium, the fault line should be inferred underneath the younger sediments 2) faults striking within 45° of one another should be treated as a continuous fault line and 3) a step-over can link together faults at least 5 km apart. These definitions were applied to fault lines in Southern California. For example, many of the along-strike faults lines in the Mojave Desert are treated as a single fault trending from the Pinto Mountain to the Garlock fault. In addition, the Rose Canyon and Newport-Inglewood faults are treated as a single fault line. We used these more generous fault lengths, and the Wells and Coppersmith regression, to estimate the maximum magnitude (mx) for the major faults in southern California. Then we compared our mx values with those proposed by CALTRANS, and those assumed in the 2002 USGS/CGS hazard model. To calculate the planning magnitude mp we assumed a truncated Gutenberg-Richter magnitude distribution with parameters a, b, and mx. We fixed b and solved for the a-value in terms of mx, b, and the tectonic moment rate. For many faults mp is relatively insensitive to mx and typically falls off at higher magnitudes because the a-value decreases with increasing mx when the moment rate is constrained. Furthermore, we find that by increasing mx the cumulative earthquake rate actually decreases for smaller magnitude (5 and 6) events. This suggests that fewer magnitude 5 and 6 earthquakes are required to balance the moment budget if larger, but highly infrequent, earthquakes are allowed to occur.

  19. Fault Creep on the Hayward Fault, CA: Implications for Fault Properties and Patterns of Moment Release

    NASA Astrophysics Data System (ADS)

    Malservisi, R.; Furlong, K. P.; Gans, C.

    2001-12-01

    The seismic risk associated with creeping faults such as the Hayward fault (San Francisco Bay Area, CA) will depend on the rate of moment accumulation (slip deficit) on the fault plane, on the specific geometry of locked and free portions of the fault, and on the interactions between the fault zone and the surrounding lithosphere. Using a visco-elastic finite-element model, we have investigated fault zone geometries and physical characteristics that produce the observed surface creep on the Hayward fault, driven by far field plate motions. This differs from most previous analyses in that we do not explicitly specify fault-creep on fault patches, but rather allow the rheology, geometry, and mechanics of the fault system to determine patterns of fault creep. Our model results show that for models that match the observed surface creep data, there is a smooth transition in creep rate from regions free to creep to locked patches. This behavior leads to "creepable" (low friction) areas that accumulate a high slip deficit as compared to other low friction segments of the fault. Interestingly, a comparison of the creep pattern from our results with Hayward Fault microseismicity indicates that events cluster in the locked areas and in transition zones -the "creepable" regions with a high creeping velocity gradient. Furthermore, seismicity seems to be more diffuse around the fault plane in the locked and transition zones than on the `creepable' areas with relatively high creep rates. Although the total amount of seismic moment stored on the Hayward fault does not differ significantly between our model and previous ones, and thus the potential magnitude of earthquakes are similar in all creep models, there is a difference in the location of fault patches with significant slip deficit. Additionally, since in our models there are regions free to creep that still accumulate a high slip deficit, energy release during rupture may vary among the models. That is, if the velocity of rupture propagation on the fault varies with fault friction (i.e. higher velocity in areas with low friction and lower velocity in locked areas), regions of low friction but high slip deficit on our models may become loci of enhanced rate of moment release, changing the patterns of ground shaking at sites along the fault.

  20. Paleoseismic results of the east strand of the Lower Tagus Valley Fault Zone, Central Portugal.

    NASA Astrophysics Data System (ADS)

    Canora, Carolina; Vilanova, Susana; Besana-Ostman, Glenda; Heleno, Sandra; Fonseca, Joao; Domingues, Ana; Pinheiro, Patricia; Pinto, Luis

    2014-05-01

    The Lower Tagus Valley Fault Zone (LTVFZ) is a northeast-southwest trending tectonic structure located within the Lower Tagus Valley (LTV), in central Portugal associated with at least two historical events: the 1909 Mw 6.0-6.2 Benavente earthquake and the 1531 Mw 6.9 earthquake. Recent investigations indicate that the relatively linear valley associated with the Lower Tagus River is controlled by active faults in varying geometry and slip rates. Based on mapped traces, LTVFZ is about 80 kilometers long and transects Miocene to Holocene deposit. The east and west strands of the fault zone may have different level of activity based on the variable clarity of mapped morphological expressions. In recent studies new fault strands were identified using aerial photos and field survey on eastern side of LTV. These eastern faults have a trend that almost parallel those active traces previously mapped by Besana-Ostman et al., 2012 on the western side of the valley. Quaternary activity of this fault deforms fluvial terraces and produces morphological features related to left-lateral strike-slip movement like river offsets. In this work we present the results of the first paleoseismic analysis carried out on this strand of the fault. Trenching studies shows that surface rupture events have occurred affecting Tagus fluvial terraces. The geometry of faulting exposed in the trench provides valuable insights into the kinematics of the fault, and provides a preliminary minimum net slip rate. New relative ages of the deformation are established on preliminary trenching results, and recurrence intervals will be determined upon receipt of results of sample processing for C14 dating. The aim of this work is to contribute with new data to parameterize the paleoseismic activity of this active fault in order to be included in the future seismic hazard assessments. Further studies are proposed and underway to characterize the LTVFZ, including high-resolution LIDAR images analysis, more active fault mapping and paleoseismic excavations.

  1. The San Andreas Fault and a Strike-slip Fault on Europa

    NASA Technical Reports Server (NTRS)

    1998-01-01

    The mosaic on the right of the south polar region of Jupiter's moon Europa shows the northern 290 kilometers (180 miles) of a strike-slip fault named Astypalaea Linea. The entire fault is about 810 kilometers (500 miles) long, the size of the California portion of the San Andreas fault on Earth which runs from the California-Mexico border north to the San Francisco Bay.

    The left mosaic shows the portion of the San Andreas fault near California's san Francisco Bay that has been scaled to the same size and resolution as the Europa image. Each covers an area approximately 170 by 193 kilometers(105 by 120 miles). The red line marks the once active central crack of the Europan fault (right) and the line of the San Andreas fault (left).

    A strike-slip fault is one in which two crustal blocks move horizontally past one another, similar to two opposing lanes of traffic. The overall motion along the Europan fault seems to have followed a continuous narrow crack along the entire length of the feature, with a path resembling stepson a staircase crossing zones which have been pulled apart. The images show that about 50 kilometers (30 miles) of displacement have taken place along the fault. Opposite sides of the fault can be reconstructed like a puzzle, matching the shape of the sides as well as older individual cracks and ridges that had been broken by its movements.

    Bends in the Europan fault have allowed the surface to be pulled apart. This pulling-apart along the fault's bends created openings through which warmer, softer ice from below Europa's brittle ice shell surface, or frozen water from a possible subsurface ocean, could reach the surface. This upwelling of material formed large areas of new ice within the boundaries of the original fault. A similar pulling apart phenomenon can be observed in the geological trough surrounding California's Salton Sea, and in Death Valley and the Dead Sea. In those cases, the pulled apart regions can include upwelled materials, but may be filled in mostly by sedimentary and erosional material deposited from above. Comparisons between faults on Europa and Earth may generate ideas useful in the study of terrestrial faulting.

    One theory is that fault motion on Europa is induced by the pull of variable daily tides generated by Jupiter's gravitational tug on Europa. The tidal tension opens the fault; subsequent tidal stress causes it to move lengthwise in one direction. Then the tidal forces close the fault up again. This prevents the area from moving back to its original position. If it moves forward with the next daily tidal cycle, the result is a steady accumulation of these lengthwise offset motions.

    Unlike Europa, here on Earth, large strike-slip faults such as the San Andreas are set in motion not by tidal pull, but by plate tectonic forces from the planet's mantle.

    North is to the top of the picture. The Earth picture (left) shows a LandSat Thematic Mapper image acquired in the infrared (1.55 to 1.75 micrometers) by LandSat5 on Friday, October 20th 1989 at 10:21 am. The original resolution was 28.5 meters per picture element.

    The Europa picture (right)is centered at 66 degrees south latitude and 195 degrees west longitude. The highest resolution frames, obtained at 40 meters per picture element with a spacecraft range of less than 4200 kilometers (2600 miles), are set in the context of lower resolution regional frames obtained at 200 meters per picture element and a range of 22,000 kilometers (13,600 miles). The images were taken on September 26, 1998 by the Solid State Imaging (SSI) system on NASA's Galileo spacecraft.

    The Jet Propulsion Laboratory, Pasadena, CA manages the Galileo mission for NASA's Office of Space Science, Washington, DC.

    This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://galileo.jpl.nasa.gov. Background information and educational context for the images can be found at URL HTTP://www.jpl.nasa.gov/galileo/sepo

  2. Micro-geomorphology Surveying and Analysis of Xiadian Fault Scarp, China

    NASA Astrophysics Data System (ADS)

    Ding, R.

    2014-12-01

    Historic records and field investigations reveal that the Mw 8.0 Sanhe-Pinggu (China) earthquake of 1679 produced a 10 to 18 km-long surface rupture zone, with dominantly dip-slip accompanied by a right-lateral component along the Xiadian fault, resulting in extensive damage throughout north China. The fault scarp that was coursed by the co-seismic ruptures from Dongliuhetun to Pangezhang is about 1 to 3 meters high, and the biggest vertical displacement locates in Pangezhuang, it is easily to be seen in the flat alluvial plain. But the 10 to 18 km-long surface rupture couldn't match the Mw 8.0 earthquake scale. After more than 300 years land leveling, the fault scarps in the meizoseismal zone which is farmland are retreat at different degree, some small scarps are becoming disappeared, so it is hard to identify by visual observation in the field investigations. The meizoseismal zone is located in the alluvial plain of the Chaobai river and Jiyun river, and the fault is perpendicular to the river. It is easy to distinguish fault scarps from erosion scarps. Land leveling just changes the slope of the fault scarp, but it can't eliminate the height difference between two side of the fault. So it is possible to recover the location and height of the fault scarp by using Digital Elevation Model (DEM) analysis and landform surveying which is constrained by 3D centimeter-precision RTK GPS surveying method in large scale crossing the fault zone. On the base of the high-precision DEM landform analysis, we carried out 15 GPS surveying lines which extends at least 10km for each crossing the meizoseismal zone. Our findings demonstrate that 1) we recover the complete rupture zone of the Sanhe-Pinggu earthquake in 1679, and survey the co-seismic displacement at 15 sites; 2) we conform that the Xiadian fault scarp is consist of three branches with left stepping. Height of the scarp is from 0.5 to 4.0 meters, and the total length of the scarp is at least 50km; 3) Combined with the analysis of offset strata of the trench, we conform that the middle segment of the fault scarp is made by 1679 earthquake; 4) The fault scarp strikes along with the Ju river at the northeast segment of the Xiadian fault which course the asymmetrical valley geomorphology.

  3. The Nile River

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This image of the northern portion of the Nile River was captured by MISR's nadir camera on January 30, 2001 (Terra orbit 5956). The Nile is the longest river in the world, extending for about 6700 kilometers from its headwaters in the highlands of eastern Africa. At the apex of the fertile Nile River Delta is the Egyptian capital city of Cairo. To the west are the Great Pyramids of Giza. North of here the Nile branches into two distributaries, the Rosetta to the west and the Damietta to the east. Also visible in this image is the Suez Canal, a shipping waterway connecting Port Said on the Mediterranean Sea with the Gulf of Suez. The Gulf is an arm of the Red Sea, and is located on the righthand side of the picture. Image credit: NASA/GSFC/LaRC/JPL, MISR Team.

  4. From accommodation zones to metamorphic core complexes: Tracking the progressive development of major normal fault systems

    SciTech Connect

    Faulds, J.E. . Dept. of Geology)

    1992-01-01

    The along-strike dimension in rifted continental crust is critical to assessing models of continental extension because individual normal faults or fault systems can potentially be traced from their tips in accommodation zones to their culminations in metamorphic core complexes. Accommodation zones and the linkages between the zones and core complexes have not been thoroughly studied or incorporated extensively into models of continental extension. Regionally extensive, gently dipping normal faults (i.e., detachment faults) that surface in metamorphic core complexes terminate and flip polarity in accommodation zones. Diametrical lateral transport of upper-plate rocks in positively dipping detachment terranes should presumably induce strike-slip faulting on segments of accommodation zones paralleling the extension direction. Most accommodation zones correspond, however, to belts of intermeshing conjugate normal faults with little strike-slip faulting. Normal faults simply terminate along-strike in the zones with little, if any, transfer of slip to strike-slip faults. Decreases in cumulative strain within individual normal fault systems toward some accommodation zones cannot alone account for the lack of strike-slip faulting. These findings pose a serious challenge to generally accepted notions of large-magnitude, lateral motion of parts of detachment terranes. Large-scale lateral translations of rifted continental crust may be governed more by discrete axes of extension than by detachment geometries. The dovetail-like interfingering of conjugate normal fault systems and attendant tilt-block domains observed in some accommodation zones (e.g., Colorado River extensional corridor, US) does suggest, however, that at least some major normal faults projecting into the zones from metamorphic core complexes have listric geometries that flatten out at relatively shallow depths.

  5. Development of offset channels across the San Andreas fault

    NASA Astrophysics Data System (ADS)

    Ouchi, Shunji

    2005-08-01

    The San Andreas fault offsets some small gullies incising the relatively flat surfaces in the Carrizo Plain, California. Among these gullies, those with larger drainage basins have larger offsets, probably because gullies that have larger floods can keep the channels entrenched and subjected to the fault displacement longer. On the other hand, older offset channels in the area, which have much larger offsets, indicate that the gradual shift to straighter courses seems probable only for offset channels able to keep and accumulate the offset for a long time. The strike-slip fault displacement offsets a channel as much as the channel can follow with some modification by fluvial processes until overbank floods at the upper bend induce channel avulsion to a straighter course, or until the channel is captured by the beheaded and abandoned downstream reach of the adjacent channel moved with the fault displacement. The offset channel promotes aggradation upstream from the upper bend, and this makes the channel increasingly susceptible to overbank floods. The older offset channels are confined in valleys, and this condition is apparently preventive of channel avulsion or capture. The strike-slip fault displacement also deforms longitudinal profiles of channels. Assuming that the elimination of discontinuities in the longitudinal profile is the main response of fluvial processes to the deformation by fault displacement, nearly continuous longitudinal profiles of some old offset channels seem to indicate the full adjustment, the condition in which no more changes will occur as a response to fault displacement until the next fault slip deforms them. The irregularities in longitudinal profiles of other offset channels indicate that the channel adjustment by fluvial processes may be occurring but not enough to eliminate the irregularities. An offset river can attain a continuous longitudinal profile if it has enough time to adjust its longitudinal profile after the fault displacement. Otherwise, the discontinuity reflecting a various degree of adjustment would remain in the longitudinal profile until channel avulsion or capture occurs. The degree of adjustment and the probability of channel avulsion or capture depend highly on the fluvial ability and condition of each river as well as the time after the deformation.

  6. Active faulting on the Wallula fault within the Olympic-Wallowa Lineament (OWL), eastern Washington State

    NASA Astrophysics Data System (ADS)

    Sherrod, B. L.; Lasher, J. P.; Barnett, E. A.

    2013-12-01

    Several studies over the last 40 years focused on a segment of the Wallula fault exposed in a quarry at Finley, Washington. The Wallula fault is important because it is part of the Olympic-Wallowa lineament (OWL), a ~500-km-long topographic and structural lineament extending from Vancouver Island, British Columbia to Walla Walla, Washington that accommodates Basin and Range extension. The origin and nature of the OWL is of interest because it contains potentially active faults that are within 50 km of high-level nuclear waste facilities at the Hanford Site. Mapping in the 1970's and 1980's suggested the Wallula fault did not offset Holocene and late Pleistocene deposits and is therefore inactive. New exposures of the Finley quarry wall studied here suggest otherwise. We map three main packages of rocks and sediments in a ~10 m high quarry exposure. The oldest rocks are very fine grained basalts of the Columbia River Basalt Group (~13.5 Ma). The next youngest deposits include a thin layer of vesicular basalt, white volcaniclastic deposits, colluvium containing clasts of vesicular basalt, and indurated paleosols. A distinct angular unconformity separates these vesicular basalt-bearing units from overlying late Pleistocene flood deposits, two colluvium layers containing angular clasts of basalt, and Holocene tephra-bearing loess. A tephra within the loess likely correlates to nearby outcrops of Mazama ash. We recognize three styles of faults: 1) a near vertical master reverse or oblique fault juxtaposing very fine grained basalt against late Tertiary-Holocene deposits, and marked by a thick (~40 cm) vertical seam of carbonate cemented breccia; 2) subvertical faults that flatten upwards and displace late Tertiary(?) to Quaternary(?) soils, colluvium, and volcaniclastic deposits; and 3) flexural slip faults along bedding planes in folded deposits in the footwall. We infer at least two Holocene earthquakes from the quarry exposure. The first Holocene earthquake deformed the angular unconformity and resulted in deposition of the lower clast-rich colluvium. A thin layer of pre-Mazama (>7600 years B.P.) loess caps the colluvium and post-dates the earthquake. The second earthquake is marked by shearing of the lower colluvium by small faults emanating from the carbonate-cemented breccia layer, and probable folding of the lower colluvium. A thin layer of clast-rich colluvium marks this youngest earthquake, the distal parts of which bury loess containing Mazama tephra. The preserved basalt scarp in the outcrop suggests between 1.8 and 2.8 m of post-flood vertical displacement. Faint straie on the master fault surface are subhorizontal and suggest a reverse oblique mechanism for these earthquakes, consistent with dextral offset on the Wallula fault zone inferred from offset aeromagnetic anomalies associated with ~8.5 Ma basalt dikes (Blakely and others, this meeting).

  7. Fluid involvement in normal faulting

    NASA Astrophysics Data System (ADS)

    Sibson, Richard H.

    2000-04-01

    Evidence of fluid interaction with normal faults comes from their varied role as flow barriers or conduits in hydrocarbon basins and as hosting structures for hydrothermal mineralisation, and from fault-rock assemblages in exhumed footwalls of steep active normal faults and metamorphic core complexes. These last suggest involvement of predominantly aqueous fluids over a broad depth range, with implications for fault shear resistance and the mechanics of normal fault reactivation. A general downwards progression in fault rock assemblages (high-level breccia-gouge (often clay-rich) → cataclasites → phyllonites → mylonite → mylonitic gneiss with the onset of greenschist phyllonites occurring near the base of the seismogenic crust) is inferred for normal fault zones developed in quartzo-feldspathic continental crust. Fluid inclusion studies in hydrothermal veining from some footwall assemblages suggest a transition from hydrostatic to suprahydrostatic fluid pressures over the depth range 3-5 km, with some evidence for near-lithostatic to hydrostatic pressure cycling towards the base of the seismogenic zone in the phyllonitic assemblages. Development of fault-fracture meshes through mixed-mode brittle failure in rock-masses with strong competence layering is promoted by low effective stress in the absence of thoroughgoing cohesionless faults that are favourably oriented for reactivation. Meshes may develop around normal faults in the near-surface under hydrostatic fluid pressures to depths determined by rock tensile strength, and at greater depths in overpressured portions of normal fault zones and at stress heterogeneities, especially dilational jogs. Overpressures localised within developing normal fault zones also determine the extent to which they may reutilise existing discontinuities (for example, low-angle thrust faults). Brittle failure mode plots demonstrate that reactivation of existing low-angle faults under vertical σ1 trajectories is only likely if fluid overpressures are localised within the fault zone and the surrounding rock retains significant tensile strength. Migrating pore fluids interact both statically and dynamically with normal faults. Static effects include consideration of the relative permeability of the faults with respect to the country rock, and juxtaposition effects which determine whether a fault is transmissive to flow or acts as an impermeable barrier. Strong directional permeability is expected in the subhorizontal σ2 direction parallel to intersections between minor faults, extension fractures, and stylolites. Three dynamic mechanisms tied to the seismic stress cycle may contribute to fluid redistribution: (i) cycling of mean stress coupled to shear stress, sometimes leading to postfailure expulsion of fluid from vertical fractures; (ii) suction pump action at dilational fault jogs; and, (iii) fault-valve action when a normal fault transects a seal capping either uniformly overpressured crust or overpressures localised to the immediate vicinity of the fault zone at depth. The combination of σ2 directional permeability with fluid redistribution from mean stress cycling may lead to hydraulic communication along strike, contributing to the protracted earthquake sequences that characterise normal fault systems.

  8. Fault management for data systems

    NASA Technical Reports Server (NTRS)

    Boyd, Mark A.; Iverson, David L.; Patterson-Hine, F. Ann

    1993-01-01

    Issues related to automating the process of fault management (fault diagnosis and response) for data management systems are considered. Substantial benefits are to be gained by successful automation of this process, particularly for large, complex systems. The use of graph-based models to develop a computer assisted fault management system is advocated. The general problem is described and the motivation behind choosing graph-based models over other approaches for developing fault diagnosis computer programs is outlined. Some existing work in the area of graph-based fault diagnosis is reviewed, and a new fault management method which was developed from existing methods is offered. Our method is applied to an automatic telescope system intended as a prototype for future lunar telescope programs. Finally, an application of our method to general data management systems is described.

  9. Geotechnical reconnaissance of the 2002 Denali fault, Alaska, earthquake

    USGS Publications Warehouse

    Kayen, R.; Thompson, E.; Minasian, D.; Moss, R.E.S.; Collins, B.D.; Sitar, N.; Dreger, D.; Carver, G.

    2004-01-01

    The 2002 M7.9 Denali fault earthquake resulted in 340 km of ruptures along three separate faults, causing widespread liquefaction in the fluvial deposits of the alpine valleys of the Alaska Range and eastern lowlands of the Tanana River. Areas affected by liquefaction are largely confined to Holocene alluvial deposits, man-made embankments, and backfills. Liquefaction damage, sparse surrounding the fault rupture in the western region, was abundant and severe on the eastern rivers: the Robertson, Slana, Tok, Chisana, Nabesna and Tanana Rivers. Synthetic seismograms from a kinematic source model suggest that the eastern region of the rupture zone had elevated strong-motion levels due to rupture directivity, supporting observations of elevated geotechnical damage. We use augered soil samples and shear-wave velocity profiles made with a portable apparatus for the spectral analysis of surface waves (SASW) to characterize soil properties and stiffness at liquefaction sites and three trans-Alaska pipeline pump station accelerometer locations. ?? 2004, Earthquake Engineering Research Institute.

  10. Fault architecture, fault rocks and fault rock properties in carbonate rocks

    NASA Astrophysics Data System (ADS)

    Bauer, Helene; Decker, Kurt

    2010-05-01

    Fault architecture, fault rocks and fault rock properties in carbonate rocks The current study addresses a comparative analysis of fault zones in limestone and dolomite rocks comparing the architecture of fault core and damage zones, fault rocks, and the hydrodynamic properties of faults exposed in the Upper Triassic Wetterstein Fm. of the Hochschwab Massif (Austria). All analysed faults are sinistral strike-slip faults, which formed at shallow crustal depth during the process of eastward lateral extrusion of the Eastern Alps in the Oligocene and Lower Miocene Fault zones in limestone tend to be relatively narrow zones with distinct fault core and damage zones. Fault cores, which include the principle slip surface of the fault, are characterized by cataclastic fault rock associated with slickensides separating strands of catalasite from surrounding host rock or occurring between different types of cataclasite. Cataclasites differ in terms of fragment size, matrix content and the angularity of fragments,. Cataclasite fabrics indicate progressive cataclasis and substantial displacement across the fault rock. Fault core heterogeneity tends to decrease within more evolved (higher displacement) faults. In all fault cores cataclasites are localized within strands, which connect to geometrically complex anastomosing volumes of fault rock. The 3D geometry of such fault cores is difficult to resolve on the outcrop scale. Beside cataclastic flow pressure solution, overprinting cataclastic fabrics, could be documented within fault zones. Damage zones in limestone fault zones are characterized by intensively fractured (jointed) host rock and dilatation breccias, indicating dilatation processes and peripheral wall rock weakening accompanying the growth of the fault zone. Dilatation breccias with high volumes of carbonate cement indicate these processes are related to high fluid pressure and the percolation of large volumes of fluid. Different parts of the damage zones were differentiated on the base of variable fracture densities. Fracture densities (P32 in m² joint surfaces per m³ rock) generally vary along all investigated faults. They are especially high in more evolved (higher displacement) fault zones where they are associated with large-scale Riedel sehars and in parts of the damage zones, that are next to the fault cores. The assessment of the abundance of small-scale fractures uses fracture facies as an empirical classification providing semi-quantitative estimates of fracture density and abundance. Different units were assigned to fracture facies 1 to 4, with fracture facies 4 indicating highest fracture density. Fault zones in dolomite tend to have several fault cores localized within wider zones of fractured wall rock (damage zones), even at low strain. Compared to fault zones with similar displacement in limestone, damage zones in dolomite tend to be wider and have higher fracture densities. Dilatation breccias are more abundant. A clear separation of fault core and damage zone is more difficult. Damage zones observed at the lateral (mode III) tips of the analysed strike-slip faults show that hydraulic fracturing and fluid flow through the propagating fault are of major importance for its evolution. A typical transition from the wall rock ahead of the propagating fault to the core of the slipped fault includes: densely jointed wall rock, wall rock with abundant cement-filled tension gashes, dilatation breccia and cataclasite reworking both dilatation breccia and wall rock. The detailed documentation of different fault zone units is supplemented by porosity measurements in order to assess the hydrogeological properties of the fault zones. High permeability units are first of all located in the damage zones, characterized by high fracture densities. Porosity measurements on fault rocks showed highest porosity (up to 6%) for fractured wall rocks (fracture facies 4) and dilatation breccias (porosity of undeformed wall rock: 1,5 % average, 2 % maximum). Thin sections prove that most of the porosity is carried by uncemented fractures. Fracture porosity therefore is the controlling factor of fault zone permeability. The different types of cataclasite in fault cores show low intra-granular porosities (average 2,5 %) and very low fracture density. They therefore are classified as low-permeability units.

  11. Lidar reveals paleoseismic sites and recent strike-slip and thrust faulting along the central Alpine Fault, New Zealand

    NASA Astrophysics Data System (ADS)

    De Pascale, G. P.; Langridge, R. M.; Davies, T. R.

    2013-12-01

    In the South Island of New Zealand, the dextral-reverse Alpine fault forms the major plate boundary structure between the Pacific and Australian plates and is thought to fail in large to great earthquakes approximately every 100 to 400 years, with the most recent major surface rupture event occurring in 1717 AD. We used a recently collected lidar dataset to evaluate the central section of the fault to both measure recent slip along the fault, recent co-seismic uplift, and to find new paleoseismic sites. The new high-resolution topography in the dense temperate rainforest allowed insight into the fault that was previously unavailable. Lidar mapping, combined with field mapping facilitated the discovery of a multi-event thrust fault scarp of the Alpine Fault that was later trenched at Gaunt Creek. C-14 dating of units in the trench and mapping there, show that the last earthquake was probably the 1717 event. Along the length of the lidar survey, small (< 25 m) dextral offsets were also mapped along the fault, which were rated for quality, and then visited in the field. The lidar itself was a guide to locate these offsets, and the offset measurements in the field have lower uncertainties than the lidar resolution; dextral slip in the 1717 earthquake here was c. 7 m × 1 m. Additional sites with evidence for cumulative slip were also mapped in the field which showing repetitive slip of ~ 7 to 8 m per event for the past three surface ruptures on the fault. Sag ponds discovered during field mapping are important new targets for investigation and will likely yield slip-rate information here for the correlation of slip with events. Additional field mapping near the Whataroa River and Mint Creek demonstrates that between debris flow fans that cross the Alpine Fault at the rangefront of the Southern Alps, preservation of strike-slip scarps is rare due to post-earthquake deposition and erosion. However, one likely scarp was found in a post-earthquake aggradation surface, along strike from a clear-strike slip trace, between two post-1717 fans. Based on field and lidar mapping, this scarp likely formed during the 1717 earthquake in pre-1717 Whataroa River outwash deposits.

  12. River Sinuosity Classification - Case study in the Pannonian Basin

    NASA Astrophysics Data System (ADS)

    Petrovszki, J.; Székely, B.; Timár, G.

    2012-04-01

    A new evaluation method is proposed to classify the multiple window-size based sinuosity spectrum, in order to minimize the possible human interpretation error. If the river is long enough for the analysis, the classification could be similarly useful as the sinuosity spectrum is, but sometimes it is more straightforward. Furthermore, for the classification, we did not need the main parameters of the river, e.g. the bankfull discharge. The river sinuosity values were studied in the Pannonian Basin in order to reveal neotectonic influence on their abrupt changes. The map sheets of the Second Military Survey of the Habsburg Empire were used to digitize the natural, pre-regulation meandering river thalwegs. 28 rivers were studied, and the connection between the known fault lines and the river sinuosity changes was detected in 36 points, along 26 structural lines. An unsupervised ISOCLASS classification was carried out on these data, and the sinuosity values were divided into 5 classes. Because of the sinuosity calculation method, 25 kilometer-long river sections are missing at the two endpoints of the channel. So sometimes the displayed section of the river does not cross to the faults represented on the neotectonic map. In the other cases, where the faults are crossing the rivers, the results are corresponding with the results of the sinuosity spectrum: the river-points on the two sides of the faults belong to different classes. The connection between these fault lines and the change of river sinuosity classes was detected in 23 points, along 16 structural lines The research is made in the frame of project OTKA-NK83400 (SourceSink Hungary). The European Union and the European Social Fund also have provided financial support to the project under the grant agreement no. TÁMOP 4.2.1./B-09/1/KMR-2010-0003.

  13. Fault-tolerant processing system

    NASA Technical Reports Server (NTRS)

    Palumbo, Daniel L. (Inventor)

    1996-01-01

    A fault-tolerant, fiber optic interconnect, or backplane, which serves as a via for data transfer between modules. Fault tolerance algorithms are embedded in the backplane by dividing the backplane into a read bus and a write bus and placing a redundancy management unit (RMU) between the read bus and the write bus so that all data transmitted by the write bus is subjected to the fault tolerance algorithms before the data is passed for distribution to the read bus. The RMU provides both backplane control and fault tolerance.

  14. Fault interaction near Hollister, California

    SciTech Connect

    Mavko, G.M.

    1982-09-10

    A numerical model is used to study fault stress slip near Hollister, California. The geometrically complex system of interacting faults, including the San Andreas, Calaveras, Sargent, and Busch faults, is approximated with a two-dimensional distribution of short planar fault segments in an elastic medium. The steady stress and slip rate are simulated by specifying frictional strength and stepping the remote stress ahead in time. The resulting computed fault stress is roughly proportional to the observed spatial density of small earthquakes, suggesting that the distinction between segments characterized by earthquakes and those with aseismic creep results, in part, from geometry. A nonsteady simulation is made by introducing, in addition, stress drops for individual moderate earthquakes. A close fit of observed creep with calculated slip on the Calaveras and San Andreas faults suggests that many changes in creep rate (averaged over several months) are caused by local moderate earthquakes. In particular, a 3-year creep lag preceding the August 6, 1979, Coyote Lake earthquake on the Calaveras fault seems to have been a direct result of the November 28, 1974, Thanksgiving Day earthquake on the Busch fault. Computed lags in slip rate preceding some other moderate earthquakes in the area are also due to earlier earthquakes. Although the response of the upper 1 km of the fault zone may cause some individual creep events and introduce delays in others, the long-term rate appears to reflect deep slip.

  15. Fault interaction near Hollister, California

    NASA Astrophysics Data System (ADS)

    Mavko, Gerald M.

    1982-09-01

    A numerical model is used to study fault stress and slip near Hollister, California. The geometrically complex system of interacting faults, including the San Andreas, Calaveras, Sargent, and Busch faults, is approximated with a two-dimensional distribution of short planar fault segments in an elastic medium. The steady stress and slip rate are simulated by specifying frictional strength and stepping the remote stress ahead in time. The resulting computed fault stress is roughly proportional to the observed spatial density of small earthquakes, suggesting that the distinction between segments characterized by earthquakes and those with aseismic creep results, in part, from geometry. A nosteady simulation is made by introducing, in addition, stress drops for individual moderate earthquakes. A close fit of observed creep with calculated slip on the Calaveras and San Andreas faults suggests that many changes in creep rate (averaged over several months) are caused by local moderate earthquakes. In particular, a 3-year creep lag preceding the August 6, 1979, Coyote Lake earthquake on the Calaveras fault seems to have been a direct result of the November 28, 1974, Thanksgiving Day earthquake on the Busch fault. Computed lags in slip rate preceding some other moderate earthquakes in the area are also due to earlier earthquakes. Although the response of the upper 1 km of the fault zone may cause some individual creep events and introduce delays in others, the long-term rate appears to reflect deep slip.

  16. Active faults and surface rupture in the 12 May 2008 Sichuan earthquake

    NASA Astrophysics Data System (ADS)

    Densmore, A. L.; Li, Y.; Richardson, N.

    2008-12-01

    The 12 May 2008 Sichuan, China, earthquake displayed a complex pattern of surface rupture on at least three faults that extend for ~220 km along the Longmen Shan mountains in Sichuan Province. Two of these faults - the Beichuan and Pengguan faults - had been previously recognized as active on the basis of geological and geomorphological relationships. The active traces of the Beichuan and Pengguan faults are northeast-striking, steeply-dipping to vertical shear zones that show a combination of dextral strike-slip and thrust movement, and offset a variety of Quaternary landforms. Evidence for previous earthquakes on both faults is patchy, but available data indicate that surface-rupturing earthquakes have occurred within the last 8-12 kyr on the Beichuan fault, and within the last 1-3 kyr on the Pengguan fault. During the 12 May earthquake, up to 6 m of oblique dextral-thrust slip occurred on strands of the Beichuan fault. Slip during the early stages of the rupture was primarily thrust, and the component of strike-slip deformation became progressively more important as the rupture propagated to the northeast. In places the surface rupture appears somewhat discontinuous, and we speculate that significant near-surface deformation was absorbed by bedding-parallel slip rather than by offset along a discrete fault plane. The Pengguan fault experienced nearly pure thrust deformation along ~100 km of surface rupture, despite geomorphological evidence of Quaternary dextral strike-slip displacement. The third fault that was involved in the 12 May earthquake, informally termed the Xiaoyudong fault, is a northwest-striking, moderately west-dipping fault with approximately equal components of sinistral strike-slip and thrust deformation. The Xiaoyudong fault is largely confined to the floor of the Jian Jiang river valley and was not previously recognized as an active fault. The continuity of geological contacts on either side of the valley appears to rule out long-term displacements of more than a few km on the fault. Observations of apparent compound scarps, however, indicate that the Xiaoyudong fault likely had some surface expression in older fluvial deposits before the 12 May earthquake. Interestingly, despite the extensive surface rupture and widespread evidence for large ground motions, the density of landsliding associated with the earthquake appears to depend much more strongly on bedrock lithology than on proximity to the active fault traces.

  17. Evidence for extension of Lake Basin Fault Zone from coal bed correlations in south-central Montana and implications for hydrocarbon exploration

    SciTech Connect

    Robinson, L.N.; Barnum, B.E.

    1985-05-01

    The Lake Basin fault zone is a structural lineament that extends west-northwest across central Montana. The lineament consists mainly of en echelon northeast-striking normal faults that are surface expressions of left-lateral movement along a basement wrench fault. Information gathered from the recent field mapping of coal beds and from shallow, closely spaced drill holes in the northwest part of the Powder River basin, Montana, permit detailed coal bed correlations, which revealed another linear zone of en echelon faulting directly on the extended trend of the Lake Basin fault zone. The faulted area, herein named the Sarpy Creek area, is located 48 km (30 mi) east of Hardin, Montana. It is about 13 km (8 mi) long and 10 km (6 mi) wide and contains 20 en echelon normal faults that have an average strike of N65/sup 0/E. The Lake Basin fault zone is therefore extended 32 km (20 mi) farther southeast than previously mapped to include the Sarpy Creek area. The Lake Basin oil field, Montana, and the Ash Creek oil field, Montana and Wyoming, produce from faulted anticlinal structures that have been interpreted to be genetically related to primary wrench-fault systems-the Lake Basin fault zone and Nye-Bowler fault zone, respectively. Therefore, the faulted area of Sarpy Creek (as yet unexplored), and areas southeastward from there along the trend of the Lake Basin fault zone are possible sites for hydrocarbon accumulation.

  18. Fault current limiter

    DOEpatents

    Darmann, Francis Anthony

    2013-10-08

    A fault current limiter (FCL) includes a series of high permeability posts for collectively define a core for the FCL. A DC coil, for the purposes of saturating a portion of the high permeability posts, surrounds the complete structure outside of an enclosure in the form of a vessel. The vessel contains a dielectric insulation medium. AC coils, for transporting AC current, are wound on insulating formers and electrically interconnected to each other in a manner such that the senses of the magnetic field produced by each AC coil in the corresponding high permeability core are opposing. There are insulation barriers between phases to improve dielectric withstand properties of the dielectric medium.

  19. Perspective View, Garlock Fault

    NASA Technical Reports Server (NTRS)

    2000-01-01

    California's Garlock Fault, marking the northwestern boundary of the Mojave Desert, lies at the foot of the mountains, running from the lower right to the top center of this image, which was created with data from NASA's shuttle Radar Topography Mission (SRTM), flown in February 2000. The data will be used by geologists studying fault dynamics and landforms resulting from active tectonics. These mountains are the southern end of the Sierra Nevada and the prominent canyon emerging at the lower right is Lone Tree canyon. In the distance, the San Gabriel Mountains cut across from the leftside of the image. At their base lies the San Andreas Fault which meets the Garlock Fault near the left edge at Tejon Pass. The dark linear feature running from lower right to upper left is State Highway 14 leading from the town of Mojave in the distance to Inyokern and the Owens Valley in the north. The lighter parallel lines are dirt roads related to power lines and the Los Angeles Aqueduct which run along the base of the mountains.

    This type of display adds the important dimension of elevation to the study of land use and environmental processes as observed in satellite images. The perspective view was created by draping a Landsat satellite image over an SRTM elevation model. Topography is exaggerated 1.5 times vertically. The Landsat image was provided by the United States Geological Survey's Earth Resources Observations Systems (EROS) Data Center, Sioux Falls, South Dakota.

    Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on February 11,2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM 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-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense (DoD), and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise,Washington, DC.

    Size: Varies in a perspective view Location: 35.25 deg. North lat., 118.05 deg. West lon. Orientation: Looking southwest Original Data Resolution: SRTM and Landsat: 30 meters (99 feet) Date Acquired: February 16, 2000

  20. 20 CFR 404.507 - Fault.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... Officer § 404.507 Fault. Fault as used in without fault (see § 404.506 and 42 CFR 405.355) applies only to the individual. Although the Administration may have been at fault in making the overpayment, that... 20 Employees' Benefits 2 2014-04-01 2014-04-01 false Fault. 404.507 Section 404.507...

  1. 20 CFR 404.507 - Fault.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Officer § 404.507 Fault. Fault as used in without fault (see § 404.506 and 42 CFR 405.355) applies only to the individual. Although the Administration may have been at fault in making the overpayment, that... 20 Employees' Benefits 2 2013-04-01 2013-04-01 false Fault. 404.507 Section 404.507...

  2. 20 CFR 404.507 - Fault.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Officer § 404.507 Fault. Fault as used in without fault (see § 404.506 and 42 CFR 405.355) applies only to the individual. Although the Administration may have been at fault in making the overpayment, that... 20 Employees' Benefits 2 2012-04-01 2012-04-01 false Fault. 404.507 Section 404.507...

  3. Final Technical Report: PV Fault Detection Tool.

    SciTech Connect

    King, Bruce Hardison; Jones, Christian Birk

    2015-12-01

    The PV Fault Detection Tool project plans to demonstrate that the FDT can (a) detect catastrophic and degradation faults and (b) identify the type of fault. This will be accomplished by collecting fault signatures using different instruments and integrating this information to establish a logical controller for detecting, diagnosing and classifying each fault.

  4. The tectonic evolution of Red Sea and Gulf of Aden

    SciTech Connect

    Allen, R.B. ); Sikander, A.H. ); Abouzakhm, A.G.

    1991-08-01

    The Red Sea and Gulf of Aden, formed by rifting of the Arabian plate away from Africa, have been the subjects of numerous studies since the 1960s. Geophysical and geological data gathered during hydrocarbon exploration by several companies are being synthesized as part of the World Bank-executed Red Sea/Gulf of Aden Regional Hydrocarbon Study Project. This synthesis provides an opportunity to study the regional variation in tectonic history and structural style within the two basins, particularly toward the basin margins, where data coverage is most complete and a thinner sedimentary cover allows more reliable interpretation of deeper horizons. Based on this data, most of the Red Sea shows a similar tectonic history to that of the Gulf of Suez. Widespread normal faulting developed contemporaneous with deposition of a dominantly clastic sequence of Oligocene( ) to middle Miocene age. The faulting often dies out within or below thick middle to upper Miocene evaporite deposits with only few faults affecting the younger units. The Gulf of Aden, on the other hand, shows a strong contrast between largely west-northwest-east-southeast oriented extensional structures on land, and generally more east-west oriented extensional structures on the continental shelves and slopes. The onshore extensional structures oriented oblique to the coast, and approximately perpendicular to transform fault trends in the oceanic crust of the central Gulf of Aden. This contrast is extensional structure orientations has important implications for the tectonic evolution of the Gulf of Aden.

  5. Geology and seismic potential of the Hustain fault, Tov Province, Mongolia

    NASA Astrophysics Data System (ADS)

    Day, Paul Patrick

    The Hustain fault is a 100-km long, northeasterly-striking, active extensional structure that bounds the Tuul River Valley (TRV). The fault originated as a late Paleozoic compressional structure during closure of the Mongol-Okhotsk Ocean. After a period of geologic quiescence during the early Cenozoic, the fault was reactivated as an extensional structure and may be associated with the same extension that formed Baikal Lake. The trace of the Hustain fault is clearly visible in false-color satellite images and topographic maps due to its large escarpments, truncation of Mesozoic intrusions, and a series of active springs located in the Quaternary alluvium. A southeast-northwest extensional vector (143.3/323.33.93 azimuth) was deduced from kinematic indicators. This fault possesses a left-lateral, strike-slip component and is capable of producing Magnitude 7.5 earthquakes that could severely impact the inhabitants of nearby Ulaanbaatar.

  6. Fractal dimension of faults network in the upper silesian coal basin (Poland): Preliminary studies

    NASA Astrophysics Data System (ADS)

    Idziak, Adam; Teper, Lesław

    1996-07-01

    Fractal analysis of faults network, tremor foci spatial distribution as well as the Gutenberg-Richter relationship could further explain whether the biggest seismic events are connected with recent tectonic activity. Fractality of fault systems geometry, as a first step of the analysis, was tested fro a part of the USCB embodying the main structural units. The cluster analysis and the box counting methods were employed. The calculated fractal dimension of fault network was 1.98 for the whole area yet for considered structural units it was close to 1.6. The results point to similarity of studied fault pattern to river network. Faults within selected tectonic units make separate sets which have a distinct geometry and origin. The value of 1.6 is an upper limit to the fracture geometry of rocks that can be explained on the basis of Griffith energy balance concept.

  7. Red blood cell production

    MedlinePlus

    ... cells are an important element of blood. Their job is to transport oxygen to the body’s tissues in exchange for carbon dioxide, which is carried to and eliminated by the lungs. Red blood cells are formed in the red bone marrow of bones. Stem cells in the red bone marrow called hemocytoblasts ...

  8. RED-LETTER DAYS

    EPA Science Inventory

    The word "red-letter" is an adjective meaning "of special significance." It's origin is from the practice of marking Christian holy days in red letters on calendars. The "red-letter days" to which I refer occurred while I was a graduate student of ...

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