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Sample records for central termoelectrica san

  1. 77 FR 36041 - San Antonio Central Railroad, L.L.C.-Lease Exemption-Port Authority of San Antonio

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-15

    ... Surface Transportation Board San Antonio Central Railroad, L.L.C.--Lease Exemption--Port Authority of San Antonio San Antonio Central Railroad, L.L.C. (SAC), a noncarrier, has filed a verified notice of exemption... Authority of San Antonio (the Port), in San Antonio, Tex. This transaction is related to a...

  2. Stratigraphy, sedimentology and paleontology of lower Eocene San Jose formation, central San Juan basin, New Mexico

    SciTech Connect

    Lucas, S.G.; Smith, L.N. )

    1989-09-01

    The lower Eocene San Jose Formation in the central portion of the San Juan basin (Gobernador-Vigas Canyon area) consists of the Cuba Mesa, Regina, Llaves, and Tapicitos Members. Well log data indicate that, from its 100-m thickness, the Cuba Mesa Member thins toward the basin center and pinches out to the northeast by lat. 36{degree}40'N, long. 107{degree}19'W. The Regina Member has the most extensive outcrops in the central basin, and it decreases in sandstone/mud rock ratio to the north. The Llaves and Tapicitos Members occur only at the highest elevations, are thin due to erosion, and are not mappable as separate units. Well log data and 1,275 m of measured stratigraphic section in the Regina, Llaves, and Tapicitos Members indicate these strata are composed of approximately 35% medium to coarse-grained sandstone and 65% fine-grained sandstone and mud rock. Sedimentology and sediment-dispersal patterns indicate deposition by generally south-flowing streams that had sources to the northwest, northeast, and east. Low-sinuosity, sand-bedded, braided( ) streams shifted laterally across about 1 km-wide channel belts to produce sheet sandstones that are prominent throughout the San Jose Formation. Subtle levees separated channel environments from floodplain and local lacustrine areas. Avulsion relocated channels periodically to areas on the floodplain, resulting in the typically disconnected sheet sandstones within muddy overbank deposits of the Regina Member.

  3. Central San Juan caldera cluster: regional volcanic framework

    USGS Publications Warehouse

    Lipman, Peter W.

    2000-01-01

    Eruption of at least 8800 km3 of dacitic-rhyolitic magma as 9 major ash-slow sheets (individually 150-5000 km3) was accompanied by recurrent caldera subsidence between 28.3 and about 26.5 Ma in the central San Juan Mountains, Colorado. Voluminous andesitic-decitic lavas and breccias were erupted from central volcanoes prior to the ash-flow eruptions, and similar lava eruptions continued within and adjacent to the calderas during the period of explosive volcanism, making the central San Juan caldera cluster an exceptional site for study of caldera-related volcanic processes. Exposed calderas vary in size from 10 to 75 km in maximum diameter, the largest calderas being associated with the most voluminous eruptions. After collapse of the giant La Garita caldera during eruption if the Fish Canyon Tuff at 17.6 Ma, seven additional explosive eruptions and calderas formed inside the La Garita depression within about 1 m.y. Because of the nested geometry, maximum loci of recurrently overlapping collapse events are inferred to have subsided as much as 10-17 km, far deeper than the roof of the composite subvolcanic batholith defined by gravity data, which represents solidified caldera-related magma bodies. Erosional dissection to depths of as much as 1.5 km, although insufficient to reach the subvolcanic batholith, has exposed diverse features of intracaldera ash-flow tuff and interleaved caldera-collapse landslide deposits that accumulated to multikilometer thickness within concurrently subsiding caldera structures. The calderas display a variety of postcollapse resurgent uplift structures, and caldera-forming events produced complex fault geometries that localized late mineralization, including the epithermal base- and precious-metal veins of the well-known Creede mining district. Most of the central San Juan calderas have been deeply eroded, and their identification is dependent on detailed geologic mapping. In contrast, the primary volcanic morphology of the

  4. Groundwater Quality in the Central Eastside San Joaquin Valley, California

    USGS Publications Warehouse

    Belitz, Kenneth; Landon, Matthew K.

    2010-01-01

    The Central Eastside study unit is located in California's San Joaquin Valley. The 1,695 square mile study unit includes three groundwater subbasins: Modesto, Turlock, and Merced (California Department of Water Resources, 2003). The primary water-bearing units consist of discontinuous lenses of gravel, sand, silt, and clay, which are derived largely from the Sierra Nevada Mountains to the east. Public-supply wells provide most of the drinking water supply in the Central Eastside. Consequently, the primary aquifer in the Central Eastside study unit is defined as that part of the aquifer corresponding to the perforated interval of wells listed in the California Department of Public Health database. Public-supply wells are typically drilled to depths of 200 to 350 feet, consist of solid casing from the land surface to a depth of about 100 to 200 feet, and they are perforated below the solid casing. Water quality in the shallower and deeper parts of the aquifer system may differ from that in the primary aquifer. The Central Eastside study unit has hot and dry summers and cool, moist, winters. Average annual rainfall ranges from 11 to 15 inches. The Stanislaus, Tuolumne, and Merced Rivers, with headwaters in the Sierra Nevada Mountains, are the primary streams traversing the study unit. Land use in the study unit is approximately 59 percent (%) agricultural, 34% natural (primarily grassland), and 7% urban. The primary crops are almonds, walnuts, peaches, grapes, grain, corn, and alfalfa. The largest urban areas (2003 population in parentheses) are the cities of Modesto (206,872), Turlock (63,467), and Merced (69,512). Municipal water use accounts for about 5% of the total water use in the Central Eastside study unit, with the remainder used for irrigated agriculture. Groundwater accounts for about 75% of the municipal supply, and surface water accounts for about 25%. Recharge to the groundwater flow system is primarily from percolation of irrigation return

  5. Multibeam Data and Socio-Economic Issues in West-Central San Francisco Bay, California

    USGS Publications Warehouse

    Chin, John L.; Carlson, Paul R.; Wong, Florence L.; Cacchione, David A.

    1998-01-01

    San Francisco Bay is the largest estuary on the conterminous U.S. Pacific Coast and is one of the world's largest natural harbors. It is a biologically productive and diverse environment. San Francisco Bay has a maritime economy that annually generates over $7.5 billion, handles 50 million tons of cargo, and involves thousands of jobs. Recent investigations by the USGS in this estuary help address both socio-economic and scientific issues: *Trimming pinnacles may prevent a calamitous oil spill. *Can San Francisco Bay accept more dredge spoil? *Bay floor biological habitats are quite varied. *How thick and how variable is the sediment fill in central San Francisco Bay?

  6. Foraminifera and paleoenvironments in the Etchegoin and lower San Joaquin Formations, west-central San Joaquin valley, California

    SciTech Connect

    Lagoe, M.B.; Tenison, J.A.; Buehring, R. )

    1991-02-01

    The Etchegoin and San Joaquin formations preserve a rich stratigraphic record of paleoenvironments, deposition, and tectonics during the late Miocene-Pliocene development of the San Joaquin basin. The distribution of foraminifera within these formations can help constrain this record, which includes final filling of the basin, facies responses to sea level changes, and active movement on the San Andreas fault system. The distribution of foraminifera in core samples is analyzed from seven wells along the west-central San joaquin basin - four from Buena Vista oil field, one from western Elk Hills oil field, and two from an area just south of South Belridge oil field. A model of modern, shallow- to marginal-marine foraminiferal biofacies is used to interpret the Etchegoin-San Joaquin faunal distributions. This modern model distinguishes marsh, tidal channel, intertidal, lagoonal, littoral, and shallow sublittoral environments. Ongoing work calibrating this foraminiferal record to the lithologic and macrofossil records in addition to interpreted depositional systems within these formations will further define relationships between paleoenvironments, relative sea level, and tectonics.

  7. Hydrology of the San Luis Valley, south-central Colorado

    USGS Publications Warehouse

    Emery, P.A.; Boettcher, A.J.; Snipes, R.J.; Mcintyre, H.J.

    1969-01-01

    An investigation of the water resources of the Colorado part of the San Luis Valley was begun in 1966 by the U.S. Geological Survey, in cooperation with the Colorado Water Conservation Board. (See index map, fig. 1). The purpose of the investigation is to provide information for planning and implementing improved water-development and management practices. The major water problems in the San Luis Valley include (1) waterlogging, (2) waste of water by nonbeneficial evapotranspiration, (3) deterioration of ground-water chemical quality, and (4) failure of Colorado to deliver water to New Mexico and Texas in accordance with the Rio Grande Compact. This report describes the hydrologic environment, extent of water-resource development, and some of the problems related to that development. Information presented is based on data collected from 1966 to 1968 and on previous studies. Subsequent reports are planned as the investigation progresses. The San Luis Valley extends about 100 miles from Poncha Pass near the northeast corner of Saguache County, Colo., to a point about 16 miles south of the Colorado-New Mexico State line. The total area is 3,125 square miles, of which about 3,000 are in Colorado. The valley is nearly flat except for the San Luis Hills and a few other small areas. The Colorado part of the San Luis Valley, which is described in this report, has an average altitude of about 7,700 feet. Bounding the valley on the west are the San Juan Mountains and on the east the Sangre de Cristo Mountains. Most of the valley floor is bordered by alluvial fans deposited by streams originating in the mountains, the most extensive being the Rio Grande fan (see block diagram, fig. 2 in pocket). Most of the streamflow is derived from snowmelt from 4,700 square miles of watershed in the surrounding mountains. The northern half of the San Luis Valley is internally drained and is referred to as the closed basin. The lowest part of this area is known locally as the "sump." The

  8. Sediment Distribution in Central San Francisco Bay in the Vicinity of Raccoon Strait.

    NASA Astrophysics Data System (ADS)

    Parker, K. A.; White, L. D.; Vavro, M.; Tran, J.; Basconcillo, N.; Kheradyar, T.; Pestrong, R.

    2003-12-01

    We collected sediment grab samples from twenty-one sites distributed within a 2-km2 area in Central San Francisco Bay, including Raccoon Strait, which is located between the Tiburon Peninsula and Angel Island. We gathered these samples in May and August of 2003, dried and disaggregated them using a Gilson Sieve Tester, and analyzed the sediments by weight percent. Our purpose in monitoring sediment distributions over time in Central San Francisco Bay is to gain understanding of the oceanographic dynamics of the bay-delta estuarine system. Our initial results indicate that grain sizes range from > 2 millimeters to < 125 microns with coarser samples located at the entrance to Raccoon Strait. We anticipate collecting samples from these twenty-one sites in November of 2003, and eventually relating the sediment distribution patterns to seasonal variations in transport. This study is part of a larger-scale project involving bedform migration and current transport in Central San Francisco Bay.

  9. Origin and characteristics of discharge at San Marcos Springs, south-central Texas

    USGS Publications Warehouse

    Musgrove, MaryLynn; Crow, Cassi L.

    2013-01-01

    The Edwards aquifer in south-central Texas is one of the most productive aquifers in the Nation and is the primary source of water for the rapidly growing San Antonio area. Springs issuing from the Edwards aquifer provide habitat for several threatened and endangered species, serve as locations for recreational activities, and supply downstream users. Comal Springs and San Marcos Springs are major discharge points for the Edwards aquifer, and their discharges are used as thresholds in groundwater management strategies. Regional flow paths originating in the western part of the aquifer are generally understood to supply discharge at Comal Springs. In contrast, the hydrologic connection of San Marcos Springs with the regional Edwards aquifer flow system is less understood. During November 2008–December 2010, the U.S. Geological Survey, in cooperation with the San Antonio Water System, collected and analyzed hydrologic and geochemical data from springs, groundwater wells, and streams to gain a better understanding of the origin and characteristics of discharge at San Marcos Springs. During the study, climatic and hydrologic conditions transitioned from exceptional drought to wetter than normal. The wide range of hydrologic conditions that occurred during this study—and corresponding changes in surface-water, groundwater and spring discharge, and in physicochemical properties and geochemistry—provides insight into the origin of the water discharging from San Marcos Springs. Three orifices at San Marcos Springs (Deep, Diversion, and Weissmuller Springs) were selected to be representative of larger springs at the spring complex. Key findings include that discharge at San Marcos Springs was dominated by regional recharge sources and groundwater flow paths and that different orifices of San Marcos Springs respond differently to changes in hydrologic conditions; Deep Spring was less responsive to changes in hydrologic conditions than were Diversion Spring and

  10. 77 FR 36040 - Watco Holdings, Inc.-Continuance in Control Exemption-San Antonio Central Railroad, L.L.C.

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-15

    ... Railroad, L.L.C. Watco Holdings, Inc. (Watco), a noncarrier, has filed a verified notice of exemption pursuant to 49 CFR 1180.2(d)(2), for Watco to continue in control of San Antonio Central Railroad, L.L.C... concurrently filed verified notice of exemption in San Antonio Central Railroad, L.L.C.--Lease Exemption--...

  11. Sediment Deposition, Erosion, and Bathymetric Change in Central San Francisco Bay: 1855-1979

    USGS Publications Warehouse

    Fregoso, Theresa A.; Foxgrover, Amy C.; Jaffe, Bruce E.

    2008-01-01

    Central San Francisco Bay is the hub of a dynamic estuarine system connecting the San Joaquin and Sacramento River Deltas, Suisun Bay, and San Pablo Bay to the Pacific Ocean and South San Francisco Bay. To understand the role that Central San Francisco Bay plays in sediment transport throughout the system, it is necessary to first determine historical changes in patterns of sediment deposition and erosion from both natural and anthropogenic forces. The first extensive hydrographic survey of Central San Francisco Bay was conducted in 1853 by the National Ocean Service (NOS) (formerly the United States Coast and Geodetic Survey (USCGS)). From 1894 to 1979, four additional surveys, composed of a total of approximately 700,000 bathymetric soundings, were collected within Central San Francisco Bay. Converting these soundings into accurate bathymetric models involved many steps. The soundings were either hand digitized directly from the original USCGS and NOS hydrographic sheets (H-sheets) or obtained digitally from the National Geophysical Data Center's (NGDC) Geophysical Data System (GEODAS) (National Geophysical Data Center, 1996). Soundings were supplemented with contours that were either taken directly from the H-sheets or added in by hand. Shorelines and marsh areas were obtained from topographic sheets. The digitized soundings, depth contours, shorelines, and marsh areas were entered into a geographic information system (GIS) and georeferenced to a common horizontal datum. Using surface modeling software, bathymetric grids with a horizontal resolution of 25 m were developed for each of the five hydrographic surveys. Before analyses of sediment deposition and erosion were conducted, interpolation bias was removed and all of the grids were converted to a common vertical datum. These bathymetric grids were then used to develop bathymetric change maps for subsequent survey periods and to determine long-term changes in deposition and erosion by calculating volumes and

  12. Seismic data acquisition over San Juan volcanic field, San Juan sag, south-central Colorado

    SciTech Connect

    Henkel, R.P. )

    1989-09-01

    The San Juan sag, a foreland basin along the Uncompahgre-Brazos uplift, contains Mesozoic sediments overlain by up to 10,000 ft of Tertiary volcanics. Petroleum exploration beneath thick volcanic cover requires successful acquisition of seismic data; however, experience elsewhere has generally produced only marginal results. Commencing in 1983, Meridian Oil recorded 18 seismic lines comprising 260 mi of conventional and portable data. Noise test were performed at two sites to evaluate seismic response and to determine source and receiver parameters. Vibroseis, shothole, and surface dynamite were examined as sources and gave comparable results. Coherent noise trains with velocities from 4,000 to 8,000 ft/sec and dominant frequencies of 10 to 15 Hz were generated in the Tertiary section. The predominant factor affecting data quality was outcrop lithology. Data recorded over alluvial and other Quaternary deposits tended to be good to fair. Data quality over Tertiary volcanics was variable and highly unit dependent, ranging from fair over andesites and volcaniclastics, poor over ash-flow tuffs, and uniformly very poor over basalts. Seismic source appeared to have only a minor effect on quality. Data processing involved no unusual operations. Velocity filtering was used to suppress near-surface generated coherent noise, Refraction statics were applied to lines with significant elevation or lithologic variations. A successful acquisition program helped to establish the presence of a Mesozoic sedimentary section beneath the volcanics. these data revealed large structural features within the sedimentary section as well as a dramatic angular unconformity at the top of the Cretaceous section.

  13. 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.

  14. Dual-system Tectonics of the San Luis Range and Vicinity, Coastal Central California

    NASA Astrophysics Data System (ADS)

    Hamilton, D. H.

    2010-12-01

    The M 6.5 "San Simeon" earthquake of December 22, 2003, occurred beneath the Santa Lucia Range in coastal central California, and resulted in around $250,000,000 property damage and two deaths from collapse of an historic building in the town of Paso Robles, located 40 km from the epicenter. The earthquake and more than 10,000 aftershocks were well recorded by nearby seismographs, which permitted detailed analysis of the event (eg: McLaren et al., 2008). This analysis facilitated evaluation of the hazard of the occurrence of a similar event in the nearby San Luis Range, located along the coast west of the city of San Luis Obispo some 55 km south of the San Simeon epicenter. The future occurrence of earthquakes analogous to the 2003 event in this area had been proposed in the late 1960’s (eg: Benioff and Smith, 1967; Richter, 1969) but the apparent hazard of such occurrences came to be overshadowed by the discovery of the “Hosgri” strike slip fault passing close to the area in the offshore. However data accumulated since the early 1970’s clearly demonstrate the hazard as being partitioned between nearby earthquakes of strike slip origin, and underlying earthquakes of thrust origin analogous to that of the 2003 San Simeon earthquake. And for the onshore San Luis Range area, an underlying actively seismogenic thrust wedge appears to provide the maximum potential seismic ground motion; exceeding that potentially resulting from large events on nearby strike slip faults of the San Simeon-Hosgri system, for onshore sites. Understanding and documentation of the geology, geomorphology, tectonics and seismogenesis of the San Luis Range and vicinity has recently experienced a quantum improvement as both new and accumulated data have been analysed. An integrated interpretation of all available data now clearly shows that a dual “side by side” system of active tectonics exists in the region. Essentially the most obvious evidence for this is seen simply in the

  15. Geologic Map of the Central San Juan Caldera Cluster, Southwestern Colorado

    USGS Publications Warehouse

    Lipman, Peter W.

    2006-01-01

    The San Juan Mountains are the largest erosional remnant of a composite volcanic field that covered much of the southern Rocky Mountains in middle Tertiary time. The San Juan field consists mainly of intermediate-composition lavas and breccias, erupted about 35-30 Ma from scattered central volcanoes (Conejos Formation) and overlain by voluminous ash-flow sheets erupted from caldera sources. In the central San Juan Mountains, eruption of at least 8,800 km3 of dacitic-rhyolitic magma as nine major ash flow sheets (individually 150-5,000 km3) was accompanied by recurrent caldera subsidence between 28.3 Ma and about 26.5 Ma. Voluminous andesitic-dacitic lavas and breccias erupted from central volcanoes prior to the ash-flow eruptions, and similar lava eruptions continued within and adjacent to the calderas during the period of more silicic explosive volcanism. Exposed calderas vary in size from 10 to 75 km in maximum dimension; the largest calderas are associated with the most voluminous eruptions.

  16. Rapid Post-Miocene tectonic rotation associated with the San Gregorio Fault Zone in central California

    NASA Astrophysics Data System (ADS)

    Holm, Eric J.; Horns, Daniel M.; Verosub, Kenneth L.

    1991-12-01

    Paleomagnetic measurements of samples from the Mio-Pliocene Purisima Formation demonstrate that the Pomponio tectonic block of central coastal California has rotated clockwise by approximately 35° to 55° within the last 2.5 million years. The most likely interpretation of this data is that the Pomponio block is broken into several small blocks which have rotated by various amounts. The data suggest that rotations contribute to vertical deformation and secondary faulting within the central San Andreas Fault System, and that they play an important role in the accommodation of shear along the fault system.

  17. Anthropogenic influence on recent bathymetric change in west-central San Francisco Bay

    USGS Publications Warehouse

    Barnard, Patrick L.; Kvitek, Rikk G.

    2010-01-01

    Two multibeam sonar surveys of west-central San Francisco Bay, California, were conducted in 1997 and 2008. Bathymetric change analysis between the two surveys indicates a loss of 14.1 million cubic meters (-3.1 cm/yr-1) of sediment during this time period, representing an approximately three-fold acceleration of the rate that was observed from prior depth change analysis from 1947 to 1979 for all of Central Bay, using more spatially coarse National Ocean Service (NOS) soundings. The portions of the overlapping survey areas between 1997 and 2008 designated as aggregate mining lease sites lost sediment at five times the rate of the remainder of west-central San Francisco Bay. Despite covering only 28% of the analysis area, volume change within leasing areas accounted for 9.2 million cubic meters of sediment loss, while the rest of the area lost 4.9 million cubic meters of sediment. The uncertainty of this recent analysis is more tightly constrained due to more stringent controls on vertical and horizontal position via tightly coupled, inertially aided differential Global Positioning Systems (GPS) solutions for survey vessel trajectory that virtually eliminate inaccuracies from traditional tide modeling and vessel motion artifacts. Further, quantification of systematic depth measurement error can now be calculated through comparison of static surfaces (e.g., bedrock) between surveys using seafloor habitat maps based on acoustic backscatter measurements and ground-truthing with grab samples and underwater video. Sediment loss in the entire San Francisco Bay Coastal System during the last half-century,as estimated from a series of bathymetric change studies, is 240 million cubic meters, and most of this is believed to be coarse sediment (i.e., sand and gravel) from Central Bay and the San Francisco Bar, which is likely to limit the sand supply to adjacent, open-coast beaches. This hypothesis is supported by a calibrated numerical model in a related study that indicates

  18. Late Cenozoic stratigraphy and structure of the western margin of the central San Joaquin Valley, California

    USGS Publications Warehouse

    Lettis, William R.

    1982-01-01

    Late Cenozoic Stratigraphy Late Cenozoic deposits in the west-central San Joaquin Valley and adjacent foothills of the Diablo Range consist mainly of unconsolidated, poorly-sorted to well-sorted gravel, sand, silt and clay derived primarily from the Diablo Range and secondarily from the Sierra Nevada. Sedimentary structures, such as channeled contacts, laminated bedding, cross-stratification and clast-imbrication indicate that most of the deposits were transported and laid down by running water. These deposits are described and their facies relationships are illustrated in the 'Late Cenozoic Stratigraphy' section of this report (see Figures 17, and 26, and Table 9). Sediment shed from the Diablo Range accumulated primarily as a complex of coalescing alluvial fans on the piedmont slope of a San Joaquin Valley that at one time extended across the foothill belt to the present margin of the central Diablo Range; and as local fills within stream valleys of the Diablo Range foothills tributary to the San Joaquin Valley. These deposits are well exposed in Interstate-5 roadcuts, California Aqueduct and Delta-Mendota canal cuts, and stream banks along the many ephemeral and intermittent streams draining the Diablo Range. Sediment derived from the Sierra Nevada is confined primarily to the floodbasin of the San Joaquin Valley. It includes arkosic riverine and floodbasin deposits from the San Joaquin River and associated sloughs, as well as local ephemeral and perennial pond, swamp, oxbow-lake and lake deposits. These deposits are well-exposed in stream banks of the San Joaquin River and a few of the larger sloughs such as Salt Slough, Mud Slough and Kings Slough. Well-sorted, fine- and medium-grained, quartzose, cross-bedded sand, presumably derived from the Sierra Nevada, locally interfinger with or underlie fine-grained Coast Range alluvial-fan deposits. The sand probably originated by eolian reworking of Sierran alluvium from the floodbasin of the lower San Joaquin River

  19. Porosity evolution in reservoir sandstones in the West-Central San Joaquin basin, California

    SciTech Connect

    Horton, R.A. Jr.; McCullough, P.T.; Houghton, B.D.; Pennell, D.A.; Dunwoody, J.A. III; Menzie, R.J. Jr.

    1995-04-01

    Miocene reservoir sands (feldspathic and lithic arenites) in central San Joaquin basin oil fields show similar trends in porosity development despite differences in depositional environment, pore-fluid chemistry, and burial history. Burial and tectonic compaction caused grain rotation, deformation of altered lithics, and extensive fracturing of brittle grains, thereby eliminating most primary porosity. Diagenetic fluids, infiltrating along fractures in grains, reacted with freshly exposed mineral surfaces causing extensive leaching of framework components. All major grain types were affected but preferential removal of feldspars and lithics resulted in changes in QFL ratios. With continued compaction angular remnants of partially disolved grains were rotated and rearranged while secondary intergranular and moldic porosity collapsed to form secondary intergranular porosity. This resulted in reservoir sands that are less well sorted, more angular, and mineralogically more mature than they were at deposition. Such changes appear to widespread in the San Joaquin basin and may be more important than is generally acknowledged.

  20. The paradigm of paraglacial megafans of the San Juan river basin, Central Andes, Argentina

    NASA Astrophysics Data System (ADS)

    Suvires, Graciela M.

    2014-11-01

    The spatial distribution and several morphometric characteristics of the Quaternary alluvial fans of the San Juan River, in the province of San Juan, at the Central and Western part of Argentina, have been studied to classify them as paraglacial megafans, as well to ratify its depositional environmental conditions. The high sedimentary load exported by San Juan river from the Central Andes to the foreland depressions is estimated about 3,682,200 hm3. The large alluvial fans of Ullum-Zonda and Tulum valleys were deposited into deep tectonic depressions, during the Upper Pleistocene deglaciation stages. The outcome of collecting remotely sensed data, map and DEM data, geophysical data and much fieldwork gave access to morphometric, morphographic and morphogenetic data of these alluvial fans. The main drainage network was mapped on processed images using QGis (vers.2.0.1). Several fan morphometric parameters were measured, such as the size, the shape, the thickness, the surface areas and the sedimentary volume of exported load. The analyzed fans were accumulated in deep tectonic depressions, where the alluvium fill reaches 700 to 1200 m thick. Such fans do not reach the large size that other world megafans have, and this is due to tectonic obstacles, although the sedimentary fill average volume surpasses 514,000 hm3. The author proposes to consider Ullum-Zonda and Tulum alluvial fans as paraglacial megafans. According to the stratigraphic relationships of the tropical South American Rivers, the author considers that the San Juan paraglacial megafans would have occurred in the period before 24 ka BP , possibly corresponding to Middle Pleniglacial (ca 65-24ka BP). They record colder and more humid conditions compared with the present arid and dry conditions.

  1. Recurrence of seismic migrations along the central California segment of the San Andreas fault system

    USGS Publications Warehouse

    Wood, M.D.; Allen, S.S.

    1973-01-01

    VERIFICATIONS of tectonic concepts1 concerning seafloor spreading are emerging in a manner that has direct bearing on earthquake prediction. Although the gross pattern of worldwide seismicity contributed to the formulation of the plate tectonic hypothesis, it is the space-time characteristics of this seismicity that may contribute more toward understanding the kinematics and dynamics of the driving mechanism long speculated to originate in the mantle. If the lithosphere is composed of plates that move essentially as rigid bodies, then there should be seismic edge effects associated with this movement. It is these interplate effects, especially seismic migration patterns, that we discuss here. The unidirectional propagation at constant velocity (80 km yr-1 east to west) for earthquakes (M???7.2) on the Antblian fault for the period 1939 to 1956 (ref. 2) is one of the earliest observations of such a phenomenon. Similar studies3,4 of the Alaska Aleutian seismic zone and certain regions of the west coast of South America suggest unidirectional and recurring migrations of earthquakes (M???7.7) occur in these areas. Between these two regions along the great transform faults of the west coast of North America, there is some evidence 5 for unidirectional, constant velocity and recurrent migration of great earthquakes. The small population of earthquakes (M>7.2) in Savage's investigation5 indicates a large spatial gap along the San Andreas system in central California from 1830 to 1970. Previous work on the seismicity of this gap in central California indicates that the recurrence curves remain relatively constant, independent of large earthquakes, for periods up to a century6. Recurrence intervals for earthquakes along the San Andreas Fault have been calculated empirically by Wallace7 on the basis of geological evidence, surface measurements and assumptions restricted to the surficial seismic layer. Here we examine the evidence for recurrence of seismic migrations along

  2. Distributed Plate Boundary Deformation Across the San Andreas Fault System, Central California

    NASA Astrophysics Data System (ADS)

    Dyson, M.; Titus, S. J.; Demets, C.; Tikoff, B.

    2007-12-01

    Plate boundaries are now recognized as broad zones of complex deformation as opposed to narrow zones with discrete offsets. When assessing how plate boundary deformation is accommodated, both spatially and temporally, it is therefore crucial to understand the relative contribution of the discrete and distributed components of deformation. The creeping segment of the San Andreas fault is an ideal location to study the distribution of plate boundary deformation for several reasons. First, the geometry of the fault system in central California is relatively simple. Plate motion is dominated by slip along the relatively linear strike-slip San Andreas fault, but also includes lesser slip along the adjacent and parallel Hosgri-San Gregorio and Rinconada faults, as well as within the borderlands between the three fault strands. Second, the aseismic character of the San Andreas fault in this region allows for the application of modern geodetic techniques to assess creep rates along the fault and across the region. Third, geologic structures within the borderlands are relatively well-preserved allowing comparison between modern and ancient rates and styles of deformation. Continuous GPS stations, alignment arrays surveys, and other geodetic methods demonstrate that approximately 5 mm/yr of distributed slip is accumulated (on top of the fault slip rate) across a 70-100 km wide region centered on the San Andreas fault. New campaign GPS data also suggest 2-5 mm/yr of deformation in the borderlands. These rates depend on the magnitude of the coseismic and postseismic corrections that must be made to our GPS time series to compensate for the 2003 San Simeon and 2004 Parkfield earthquakes, which rupture faults outside, but near the edges of our GPS network. The off-fault deformation pattern can be compared to the style of permanent deformation recorded in the geologic record. Fold and thrust belts in the borderlands are better developed in the Tertiary sedimentary rocks west of

  3. Water Balance of the San Simon Groundwater Basin, El Salvador, Central America

    NASA Astrophysics Data System (ADS)

    Sullivan, M.; Lopez, D. L.; Matus, A.

    2008-05-01

    The Berlin hydrothermal field in El Salvador, Central America is located in the San Simon River Basin on the northwest slope of the Berlin-Tecapa volcanic complex, in the eastern portion of the country. This hydrothermal field, which has been exploited since 1992, is a liquid-dominated system governed by faults and caldera structures allowing infiltration and transport of meteoric fluids. San Simon River is a tributary of the Lempa River, the largest river in the country. Geophysical studies have found that the Berlin field is composed of three aquifers (Shallow, Intermediate, Deep). Exploitation involves the removal of hot fluids from the geothermal reservoir (deep aquifer) and re-injection of lower temperature fluids. This study analyzes the surficial hydrology and groundwater storage change (since exploitation) in the hydrothermal reservoir to produce a water budget. Field monitoring of springs, fumarolic activity, domestic wells, tributaries to the San Simon River, and meteorological data provide constraints on the hydrology. Springs occur in the system close to fault zones or at contacts between different lithologies. The water balance for the San Simon groundwater basin (July 2004 - June 2005) indicates that 2.51 - 3.46 E7 m3/yr of water are infiltrated to the ground, 1.30 - 1.45E7 m3/yr comprises the overland flow, 5.74 E6 m3/yr form the base flow of the San Simon River, and 1.54 E5 m3/yr is released thru the evaporation of Alegria Lake. The shallow aquifer is affected by pumping of 4.78 E6 m3/yr by the national water company. To complete the water balance of the San Simon Basin, a correlation between the composition of the fumarolic gases and the diffuse flux of soil CO2 was performed. The flux of water released from fumarolic areas was estimated at 1.48 E5 m3/yr. An analysis of the increase in chloride concentration with time in the deep aquifer and the net mass withdrawn from this aquifer allow an estimation of the decrease in storage in the hydrothermal

  4. A seismic refraction and reflection study across the central San Jacinto Basin, Southern California

    USGS Publications Warehouse

    Lee, T.-C.; Biehler, S.; Park, S.K.; Stephenson, W.J.

    1996-01-01

    The San Jacinto Basin is a northwest-trending, pullapart basin in the San Jacinto fault zone of the San Andreas fault system in southern California. About 24 km long and 2 to 4 km wide, the basin sits on a graben bounded by two strands of the San Jacinto fault zone: the Claremont Fault on the northeast and the Casa Loma Fault on the southwest. We present a case study of shallow structure (less than 1 km) in the central basin. A 2.75-km refraction line running from the northeast to southwest across the regional structural trend reveals a groundwater barrier (Offset I). Another line, bent southward and continued for 1.65-km, shows a crystalline basement offset (Offset III) near an inferred trace of the Casa Loma Fault. Although a basement refractor was not observed along the 2.75-km line, a mismatch between the estimate of its minimum depth and the basement depth determined for the 1.65-km line suggests that an offset in the basement (greater than 260 m) exists around the junction of the two refraction lines (Offset II). By revealing more faults and subtle sedimentary structures, the reflection stack sections confirm the two refraction offsets as faults. Offsets I and III each separate sediments of contrasting structures and, in addition. Offset III disrupts an unconformity. However, the sense and amount of the offset across Offset III contradict what may be expected across the Casa Loma Fault, which has its basinward basement down-thrown to about 2.5 km in the better defined southeastern part of the graben. The Casa Loma Fault trace has been mislinked in the existing geological maps and the trace should be remapped to Offset II where the reflector disruptions spread over a 400-m wide zone. Our Offset III is an unnamed, concealed fault.

  5. Deformation rates across the San Andreas Fault system, central California determined by geology and geodesy

    NASA Astrophysics Data System (ADS)

    Titus, Sarah J.

    The San Andreas fault system is a transpressional plate boundary characterized by sub-parallel dextral strike-slip faults separating internally deformed crustal blocks in central California. Both geodetic and geologic tools were used to understand the short- and long-term partitioning of deformation in both the crust and the lithospheric mantle across the plate boundary system. GPS data indicate that the short-term discrete deformation rate is ˜28 mm/yr for the central creeping segment of the San Andreas fault and increases to 33 mm/yr at +/-35 km from the fault. This gradient in deformation rates is interpreted to reflect elastic locking of the creeping segment at depth, distributed off-fault deformation, or some combination of these two mechanisms. These short-term fault-parallel deformation rates are slower than the expected geologic slip rate and the relative plate motion rate. Structural analysis of folds and transpressional kinematic modeling were used to quantify long-term distributed deformation adjacent to the Rinconada fault. Folding accommodates approximately 5 km of wrench deformation, which translates to a deformation rate of ˜1 mm/yr since the start of the Pliocene. Integration with discrete offset on the Rinconada fault indicates that this portion of the San Andreas fault system is approximately 80% strike-slip partitioned. This kinematic fold model can be applied to the entire San Andreas fault system and may explain some of the across-fault gradient in deformation rates recorded by the geodetic data. Petrologic examination of mantle xenoliths from the Coyote Lake basalt near the Calaveras fault was used to link crustal plate boundary deformation at the surface with models for the accommodation of deformation in the lithospheric mantle. Seismic anisotropy calculations based on xenolith petrofabrics suggest that an anisotropic mantle layer thickness of 35-85 km is required to explain the observed shear wave splitting delay times in central

  6. Fault coupling and potential for earthquakes on the creeping section of the central San Andreas Fault

    NASA Astrophysics Data System (ADS)

    Maurer, Jeremy; Johnson, Kaj

    2014-05-01

    The 150 km long central section of the San Andreas Fault (CSAF) in central California creeps at the surface and has not produced a large earthquake historically. However, sections of the San Andreas Fault to the north and south are known to have ruptured repeatedly in M~7-8 earthquakes. It is currently unclear whether the creeping CSAF could rupture in large earthquakes, either individually or along with earthquakes on the locked sections to the north and south. We invert Global Positioning System and interferometric synthetic aperture radar data with elastic block models to estimate the degree of locking on the CSAF and place bounds on the moment accumulation rate on the fault. We find that the inferred moment accumulation rate is highly dependent on the long-term fault slip rate, which is poorly constrained along the CSAF. The inferred moment accumulation rate, normalized by shear modulus, ranges from 3.28 × 104 to 5.85 × 107 m3/yr, which is equivalent to a Mw = 5.5-7.2 earthquake every 150 years for a long-term slip rate of 26 mm/yr and Mw = 7.3-7.65 for a long-term slip rate of 34 mm/yr. The comparisons of slip distributions with microseismicity and repeating earthquakes indicate a possible locked patch between 10 and 20 km depth on the CSAF that could potentially rupture with Mw = 6.5.

  7. Evidence for Late Oligocene-Early Miocene episode of transtension along San Andreas Fault system in central California

    SciTech Connect

    Stanley, R.G.

    1986-04-01

    The San Andreas is one of the most intensely studied fault systems in the world, but many aspects of its kinematic history remain controversial. For example, the period from the late Eocene to early Miocene is widely believed to have been a time of negligible strike-slip movement along the San Andreas fault proper, based on the rough similarity of offset of the Eocene Butano-Point of rocks Submarine Fan, the early Miocene Pinnacles-Neenach volcanic center, and an early Miocene shoreline in the northern Gabilan Range and San Emigdio Mountains. Nonetheless, evidence indicates that a late Oligocene-early Miocene episode of transtension, or strike-slip motion with a component of extension, occurred within the San Andreas fault system. The evidence includes: (1) about 22-24 Ma, widespread, synchronous volcanic activity occurred at about 12 volcanic centers along a 400-km long segment of the central California coast; (2) most of these volcanic centers are located along faults of the San Andreas system, including the San Andreas fault proper, the San Gregorio-Hosgri fault, and the Zayante-Vergeles fault, suggesting that these and other faults were active and served as conduits for magmas rising from below; (3) during the late Oligocene and early Miocene, a pull-apart basin developed adjacent to the San Andreas fault proper in the La Honda basin near Santa Cruz; and (4) during the late Oligocene and early Miocene, active faulting, rapid subsidence, and marine transgression occurred in the La Honda and other sedimentary basins in central California. The amount of right-lateral displacement along the San Andreas fault proper during this transtentional episode is unknown but was probably about 7.5-35 km, based on model studies of pull-apart basin formation. This small amount of movement is well within the range of error in published estimates of the offset of the Eocene to early Miocene geologic features noted.

  8. Deep crustal heterogeneity along and around the San Andreas fault system in central California and its relation to the segmentation

    NASA Astrophysics Data System (ADS)

    Nishigami, Kin'ya

    2000-04-01

    The three-dimensional distribution of scatterers in the crust along and around the San Andreas fault system in central California is estimated using an inversion analysis of coda envelopes from local earthquakes. I analyzed 3801 wave traces from 157 events recorded at 140 stations of the Northern California Seismic Network. The resulting scatterer distribution shows a correlation with the San Gregorio, San Andreas, Hayward, and Calaveras faults. These faults seem to be almost vertical from the surface to ˜15 km depth. Some of the other scatterers are estimated to be at shallow depths, 0-5 km, below the Diablo Range, and these may be interpreted as being generated by topographic roughness. The depth distribution of scatterers shows relatively stronger scattering in the lower crust, at ˜15-25 km depth, especially between the San Andreas fault and the Hayward-Calaveras faults. This suggests a subhorizontal detachment structure connecting these two faults in the lower crust. Several clusters of scatterers are located along the San Andreas fault at intervals of ˜20-30 km from south of San Francisco to the intersection with the Calaveras fault. This part of the San Andreas fault appears to consist of partially locked segments, also ˜20-30 km long, which rupture during M6-7 events, and segment boundaries characterized by stronger scattering and stationary microseismicity. The segment boundaries delineated by the present analysis correspond with those estimated from the slip distribution of the great 1906 San Francisco earthquake, and from the fault geometry as reported by the Working Group on California Earthquake Probabilities [1990], although the segment boundaries along the San Andreas fault in and around the San Francisco Bay area are still uncertain.

  9. Evolution of the Southern San Joaquin Basin and mid-Tertiary "transitional" tectonics, central California

    NASA Astrophysics Data System (ADS)

    Goodman, Emery D.; Malin, Peter E.

    1992-06-01

    A Cenozoic tectonic and sedimentary history is proposed for the Southern San Joaquin Basin (SSJB) and Tehachapi Mountains that evolved adjacent to the plate margin off central California. Seismic reflection, borehole, field, biostratigraphic, and paleomagnetic data are integrated into geologic and fault structure maps, cross sections, and geohistory plots and are analyzed with previous work in the region to develop a model relating the sequence, timing, and distribution of complex, tectonically linked events. The largely buried structures and strata in the SSJB preserve an unusually complete record of the mid-Tertiary transition from convergent to transform plate boundary as well as the regional transition to contraction during the Pliocene. Significant structural relief, existing across both extensional and contractile features, is preserved in the subsurface and an active fold-thrust belt propagates basinward along the margin of the U-shaped Tejon embayment The Cenozoic evolution of the SSJB reflects the regional deformation of central California as different tectonic events followed each other along the adjacent North American plate margin. Five Oligocene-Miocene basin phases are identified in the SSJB: (1) late Oligocene/early Miocene extensional subsidence, with high- and low-angle normal faulting, accompanied by volcanism and deposition of coarse syntectonic conglomerates; (2) middle Miocene uplift; (3) later mid-Miocene transtensional subsidence to lower bathyal depths; (4) alternating subsidence and uplift until the late Miocene; and (5) flexural subsidence due to Pliocene to Recent contraction. Reconstructions of mid-Tertiary California place the southern San Joaquin/Tehachapi extensional terrane as a paleotectonic block located between the Western Mojave terrane (then to the east) and the Western California terrane (then to the south and west). Regional extension occurred during a long transition period between convergent and transform boundaries along

  10. Estuarine sedimentation, sediment character, and foraminiferal distribution in central San Francisco Bay, California

    USGS Publications Warehouse

    Chin, John L.; Woodrow, Donald L.; McGann, Mary; Wong, Florence L.; Fregoso, Theresa; Jaffe, Bruce E.

    2010-01-01

    Central San Francisco Bay is the deepest subembayment in the San Francisco Bay estuary and hence has the largest water volume of any of the subembayments. It also has the strongest tidal currents and the coarsest sediment within the estuary. Tidal currents are strongest over the west-central part of central bay and, correspondingly, this area is dominated by sand-size sediment. Much of the area east of a line from Angel Island to Alcatraz Island is characterized by muddy sand to sandy mud, and the area to the west of this line is sandy. The sand-size sediment over west-central bay furthermore is molded by the energetic tidal currents into bedforms of varying sizes and wavelengths. Bedforms typically occur in water depths of 15-25 m. High resolution bathymetry (multibeam) from 1997 and 2008 allow for subdivision of the west-central bayfloor into four basic types based on morphologic expression: featureless, sand waves, disrupted/man-altered, and bedrock knobs. Featureless and sand-wave morphologies dominate the bayfloor of west-central bay. Disrupted bayfloor has a direct association with areas that are undergoing alteration due to human activities, such as sand-mining lease areas, dredging, and disposal of dredge spoils. Change detection analysis, comparing the 1997 and 2008 multibeam data sets, shows that significant change has occurred in west-central bay during the roughly 10 years between surveys. The surveyed area lost about 5.45 million m3 of sediment during the decade. Sand-mining lease areas within west-central bay lost 6.77 million m3 as the bayfloor deepened. Nonlease areas gained 1.32 million m3 of sediment as the bayfloor shallowed slightly outside of sand-mining lease areas. Furthermore, bedform asymmetry did not change significantly, but some bedforms did migrate some tens of meters. Gravity cores show that the area east of Angel and Alcatraz Islands is floored by clayey silts or silty sand whereas the area to the west of the islands is floored

  11. Geodetic measurement of deformation east of the San Andreas fault in central California

    NASA Astrophysics Data System (ADS)

    Sauber, Jeanne; Lisowski, Michael; Solomon, Sean C.

    Triangulation and trilateration data from two geodetic networks located between the San Andreas fault and the Great Valley have been used to calculate shear strain rates in the Diablo Range and to estimate the slip rate along the Calaveras and Paicines faults in central California. The shear strain rates, γ1 and γ2, were estimated independently from angle changes using Prescott's method and from the simultaneous reduction for station position and strain parameters using the DYNAP method with corrections to reduce the triangulation and trilateration data to a common reference surface. On the basis of Prescott's method, the average shear strain rate across the Diablo Range for the time period between 1962 and 1982 is 0.15±0.08 μrad/yr, with the orientation of the most compressive strain (β) at N16°E±14°. Utilizing corrections for the deflection of the vertical and the geoid reference ellipsoid separation computed on the basis of local gravity observations, γ = 0.19±0.09 μrad/yr and β = N16°E±13°. Although γ is not significantly greater than zero, at the 95% confidence level the orientation of β is similar to the direction of maximum compressive strain indicated by the orientation of major fold structures in the region (N25°E). We infer that the measured strain is due to compression across the folds of this area; the average shear straining corresponds to a relative shortening rate of 5.7±2.7 mm/yr. In contrast to the situation throughout most of the Coast Ranges where fold axes have orientations approximately parallel to the San Andreas fault, within the Diablo Range between Hollister and Coalinga the trends of the fold axes are different and are thought to be controlled by reactivation of older structures. From trilateration measurements made between 1972 and 1987 on lines that are within 10 km of the San Andreas fault, a slip rate of 10-12 mm/yr was calculated for the Calaveras-Paicines fault south of Hollister. The slip rate on the Paicines

  12. [Effects of Kaixin San formulas on behavioristics and central monoamine neurotransmitters of chronic stress rats].

    PubMed

    Liu, Wan-wan; Xu, Lu; Dong, Xian-zhe; Tan, Xiao; Wang, Shi; Zhu, Wei-yu; Liu, Ping

    2015-06-01

    The efficacy of Chinese herbal formula in treating depression has been proved in many studies. In this study, six different Kaixin San formulas were compared to investigate their effects on central monoamine neurotransmitters of chronic stress rats and against depression based on their different components in plasma, in order to discuss the efficacy-comparability relationship and the possible efficacy mechanism. The classic isolation method and the chronic unpredictable mild stress (CUMS) depression model were combined to investigate the changes in contents in hippocampus and monoamine neurotransmitters (NE, DA, 5-HT) and the components of some formulas in plasma with HPLC and UPLC-Q-TOF-MSE methods. As a result, Dingzhi Xiaowan recorded in Essential Recipes for Emergent Use Worth A Thousand significantly increased the behavioral scores, NE and 5-HT contents in hippocampus and NE, DA and 5-HT contents in cortex, with the best anti-depressant effect. Dingzhi Xiaowan recorded in Complete Records of Ancient and Modern Medical Works showed a notable increase in sucrose preference and open field score in model rats, NE content in hippocampus and NE, DA and 5-HT contents in cortex, with a certain anti anti-depressant effect. Kaixin San recorded in Ishinpo showed remarkable rise in weight of model rats. NE content in hippocampus and DA content in cortex. Puxin Decoction recorded in A Supplement to Recipes Worth A Thousand Gold showed 5-HT content in hippocampus and DA content in cortex. Kaixin San recorded in Yimenfang only showed DA content in cortex. Kaixin Wan recorded in Essential Recipes for Emergent Use Worth A Thousand did not mention the antidepressant effect. According to the results, the formulas' different anti-depressant effects may be related to the different plasma components. PMID:26552177

  13. Ground-squirrel mounds and related patterned ground along the San Andreas Fault in Central California

    USGS Publications Warehouse

    Wallace, Robert E.

    1991-01-01

    Extensive areas of mound topography and related patterned ground, apparently derived from the mounds of the California Ground Squirrel (Spermophilus beecheyi beecheyi), are in central California.  The relation of patterned ground to the San Andreas fault west of Bakersfield may provide insight into the timing of deformation along the fault as well as the history of ground squirrels.  Mound topography appears to have evolved through several stages from scattered mounds currently being constructed on newly deposited alluvial surfaces, to saturation of areas by mounds, followed by coalescence, elongation and lineation of the mounds.  Elongation, coalescence and modification of the mounds has been primarily by wind, but to a lesser extent by drainage and solifluction.  A time frame including ages of 4,000, 10,500, 29,000, and 73,000 years BP is derived by relating the patterns to slip on the San Andreas fault.  Further relating of the patterns to faulting, tilting, and warping may illuminate details of the rates and history of deformation.  Similarly, relating the patterns to the history of ground squirrel activity may help answer such problems as rates of dispersal and limits on population density.

  14. Geodetic measurement of deformation east of the San Andreas Fault in Central California

    NASA Technical Reports Server (NTRS)

    Sauber, Jeanne; Solomon, Sean C.; Lisowski, Michael

    1988-01-01

    The shear strain rates in the Diablo Range of California have been calculated, and the slip rate along the Calaveras and Paicines faults in Central California have been estimated, on the basis of triangulation and trilateration data from two geodetic networks located between the western edge of the Great Valley and the San Andreas Fault. The orientation of the principal compressive strain predicted from the azimuth of the major structures in the region is N 25 deg E, leading to an average shear strain value that corresponds to a relative shortening rate of 4.5 + or - 2.4 mm/yr. It is inferred that the measured strain is due to compression across the fold of this area. The hypothesized uniform, fault-normal compression within the Coast Ranges is not supported by these results.

  15. Precise tremor source locations and amplitude variations along the lower-crustal central San Andreas Fault

    USGS Publications Warehouse

    Shelly, David R.; Hardebeck, Jeanne L.

    2010-01-01

    We precisely locate 88 tremor families along the central San Andreas Fault using a 3D velocity model and numerous P and S wave arrival times estimated from seismogram stacks of up to 400 events per tremor family. Maximum tremor amplitudes vary along the fault by at least a factor of 7, with by far the strongest sources along a 25 km section of the fault southeast of Parkfield. We also identify many weaker tremor families, which have largely escaped prior detection. Together, these sources extend 150 km along the fault, beneath creeping, transitional, and locked sections of the upper crustal fault. Depths are mostly between 18 and 28 km, in the lower crust. Epicenters are concentrated within 3 km of the surface trace, implying a nearly vertical fault. A prominent gap in detectible activity is located directly beneath the region of maximum slip in the 2004 magnitude 6.0 Parkfield earthquake.

  16. Seismicity at Fuego, Pacaya, Izalco, and San Cristobal Volcanoes, Central America, 1973-1974

    USGS Publications Warehouse

    McNutt, S.R.; Harlow, D.H.

    1983-01-01

    Seismic data collected at four volcanoes in Central America during 1973 and 1974 indicate three sources of seismicity: regional earthquakes with hypocentral distances greater than 80 km, earthquakes within 40 km of each volcano, and seismic activity originating at the volcanoes due to eruptive processes. Regional earthquakes generated by the underthrusting and subduction of the Cocos Plate beneath the Caribbean Plate are the most prominent seismic feature in Central America. Earthquakes in the vicinity of the volcanoes occur on faults that appear to be related to volcano formation. Faulting near Fuego and Pacaya volcanoes in Guatemala is more complex due to motion on a major E-W striking transform plate boundary 40 km north of the volcanoes. Volcanic activity produces different kinds of seismic signatures. Shallow tectonic or A-type events originate on nearby faults and occur both singly and in swarms. There are typically from 0 to 6 A-type events per day with b value of about 1.3. At very shallow depths beneath Pacaya, Izalco, and San Cristobal large numbers of low-frequency or B-type events are recorded with predominant frequencies between 2.5 and 4.5 Hz and with b values of 1.7 to 2.9. The relative number of B-type events appears to be related to the eruptive states of the volcanoes; the more active volcanoes have higher levels of seismicity. At Fuego Volcano, however, low-frequency events have unusually long codas and appear to be similar to tremor. High-amplitude volcanic tremor is recorded at Fuego, Pacaya, and San Cristobal during eruptive periods. Large explosion earthquakes at Fuego are well recorded at five stations and yield information on near-surface seismic wave velocities (??=3.0??0.2 km/sec.). ?? 1983 Intern. Association of Volcanology and Chemistry of the Earth's Interior.

  17. Fault coupling and potential for earthquakes on the creeping section of the Central San Andreas Fault

    NASA Astrophysics Data System (ADS)

    Maurer, J.; Johnson, K. M.; Segall, P.

    2013-12-01

    The San Andreas Fault (SAF) has been known historically to produce large earthquakes in northern California along the northern coast section and in southern California along the Carrizo and Mojave sections. However, it is currently unclear whether the 150-km long central creeping section between these two sections could also rupture in large earthquakes. This section of the fault is known to be creeping at the surface, and in some areas may creep at nearly the long-term slip rate. We invert Global Positioning System (GPS) and Interferometric Synthetic Aperture Radar (InSAR) data to estimate the degree of locking on the central San Andreas Fault (CSAF) that place bounds on potential moment release. We use an elastic block model to compute present-day creep rates on the CSAF and compare these rates to seismicity patterns and observed surface creep rates. We find the inferred moment accumulation rate on the fault is highly dependent on the long-term fault slip rate, which is poorly constrained along the CSAF. The inferred potency accumulation rates on the creeping section, defined to be the seismic moment rate divided by shear modulus, range from 3.28x10^4 to 5.85x10^7 m^3/yr. The equivalent 150-year recurring earthquake magnitude is Mw = 5.5 - 7.2 for a long-term slip rate of 26 mm/yr and Mw = 7.3-7.65 for a long-term slip rate of 34 mm/yr. Although it is unclear how much of the accumulating moment would be released in future earthquakes, comparisons of slip distributions with seismicity indicate a possible locked patch between 10 and 20 km depth on the CSAF that could potentially rupture with Mw=6.5.

  18. Fault coupling and potential for earthquakes on the creeping section of the Central San Andreas Fault

    NASA Astrophysics Data System (ADS)

    Maurer, Jeremy Lee

    The San Andreas Fault (SAF) has been known historically to produce large earthquakes in northern California along the northern coast section and in southern California along the Carrizo and Mojave sections. However, it is currently unclear whether the 150-km long central creeping section between these two sections could also rupture in large earthquakes. This section of the fault is known to be creeping at the surface, and in some areas may creep at nearly the long-term slip rate. We invert Global Positioning System (GPS) and Interferometric Synthetic Aperture Radar (InSAR) data to estimate the degree of locking on the central San Andreas Fault (CSAF) that place bounds on potential moment release. We use an elastic block model to compute present-day creep rates on the CSAF and compare these rates to seismicity patterns and observed surface creep rates. We find the inferred moment accumulation rate on the fault is highly dependent on the long-term fault slip rate, which is poorly constrained along the CSAF. The inferred potency accumulation rates on the creeping section, defined to be the seismic moment rate divided by shear modulus, range from 3.28x104 to 5.85x107m 3/yr. The equivalent 150-year recurring earthquake magnitude is M w = 5.5 - 7.2 for a long-term slip rate of 26 mm/yr and Mw = 7.3-7.65 for a long-term slip rate of 34 mm/yr. Although it is unclear how much of the accumulating moment would be released in future earthquakes, comparisons of slip distributions with seismicity indicate a possible locked patch between 10 and 20 km depth on the CSAF that could potentially rupture with M w=6.5.

  19. Estimation of streamflow gains and losses in the lower San Antonio River watershed, south-central Texas, 2006-10

    USGS Publications Warehouse

    Lizarraga, Joy S.; Wehmeyer, Loren L.

    2012-01-01

    The U.S. Geological Survey (USGS), in cooperation with the San Antonio River Authority, the Evergreen Underground Water Conservation District, and the Goliad County Groundwater Conservation District, investigated streamflow gains and losses during 2006-10 in the lower San Antonio River watershed in south-central Texas. Streamflow gains and losses were estimated using 2006-10 continuous streamflow records from 11 continuous streamflow-gaging stations, and discrete streamflow measurements made at as many as 20 locations on the San Antonio River and selected tributaries during four synoptic surveys during 2006-7. From the continuous streamflow records, the greatest streamflow gain on the lower San Antonio River occurred in the reach from Falls City, Tex., to Goliad, Tex. The greatest streamflow gain on Cibolo Creek during 2006-10 occurred in the reach from near Saint Hedwig, Tex., to Sutherland Springs, Tex. The San Antonio River between Floresville, Tex., and Falls City was the only reach that had an estimated streamflow loss during 2006-10. During all four synoptic streamflow measurement surveys, the only substantially flowing tributary reach to the main stem of the lower San Antonio River was Cibolo Creek. Along the main stem of the lower San Antonio River, verifiable gains larger than the potential measurement error were estimated in two of the four synoptic streamflow measurement surveys. These gaining reaches occurred in the two most downstream reaches of the San Antonio River between Goliad and Farm Road (FM) 2506 near Fannin, Tex., and between FM 2506 near Fannin to near McFaddin. There were verifiable gains in streamflow in Cibolo Creek, between La Vernia, Tex., and the town of Sutherland Springs during all four surveys, estimated at between 4.8 and 14 ft3/s.

  20. Maps of Quaternary Deposits and Liquefaction Susceptibility in the Central San Francisco Bay Region, California

    USGS Publications Warehouse

    Witter, Robert C.; Knudsen, Keith L.; Sowers, Janet M.; Wentworth, Carl M.; Koehler, Richard D.; Randolph, Carolyn E.; Brooks, Suzanna K.; Gans, Kathleen D.

    2006-01-01

    This report presents a map and database of Quaternary deposits and liquefaction susceptibility for the urban core of the San Francisco Bay region. It supercedes the equivalent area of U.S. Geological Survey Open-File Report 00-444 (Knudsen and others, 2000), which covers the larger 9-county San Francisco Bay region. The report consists of (1) a spatial database, (2) two small-scale colored maps (Quaternary deposits and liquefaction susceptibility), (3) a text describing the Quaternary map and liquefaction interpretation (part 3), and (4) a text introducing the report and describing the database (part 1). All parts of the report are digital; part 1 describes the database and digital files and how to obtain them by downloading across the internet. The nine counties surrounding San Francisco Bay straddle the San Andreas fault system, which exposes the region to serious earthquake hazard (Working Group on California Earthquake Probabilities, 1999). Much of the land adjacent to the Bay and the major rivers and streams is underlain by unconsolidated deposits that are particularly vulnerable to earthquake shaking and liquefaction of water-saturated granular sediment. This new map provides a consistent detailed treatment of the central part of the 9-county region in which much of the mapping of Open-File Report 00-444 was either at smaller (less detailed) scale or represented only preliminary revision of earlier work. Like Open-File Report 00-444, the current mapping uses geomorphic expression, pedogenic soils, inferred depositional environments, and geologic age to define and distinguish the map units. Further scrutiny of the factors controlling liquefaction susceptibility has led to some changes relative to Open-File Report 00-444: particularly the reclassification of San Francisco Bay mud (Qhbm) to have only MODERATE susceptibility and the rating of artificial fills according to the Quaternary map units inferred to underlie them (other than dams - adf). The two colored

  1. Geodetic Measurement of Deformation East of the San Andreas Fault in Central California

    NASA Technical Reports Server (NTRS)

    Sauber, Jeanne M.; Lisowski, Michael; Solomon, Sean C.

    1988-01-01

    Triangulation and trilateration data from two geodetic networks located between the western edge of the Great Valley and the San Andreas fault have been used to calculate shear strain rates in the Diablo Range and to estimate the slip rate along the Calaveras and Paicines faults in Central California. Within the Diablo Range the average shear strain rate was determined for the time period between 1962 and 1982 to be 0.15 + or - 0.08 microrad/yr, with the orientation of the most compressive strain at N 16 deg E + or - 14 deg. The orientation of the principal compressive strain predicted from the azimuth of the major structures in the region is N 25 deg E. It is inferred that the measured strain is due to compression across the folds of this area: the average shear straining corresponds to a relative shortening rate of 4.5 + or - 2.4 mm/yr. From an examination of wellbore breakout orientations and the azimuths of P-axes from earthquake focal mechanisms the inferred orientation of maximum compressive stress was found to be similar to the direction of maximum compressive strain implied by the trend of local fold structures. Results do not support the hypothesis of uniform fault-normal compression within the Coast Ranges. From trilateration measurements made between 1972 and 1987 on lines that are within 10 km of the San Andreas fault, a slip rate of 10 to 12 mm/yr was calculated for the Calaveras-Paicines fault south of Hollister. The slip rate of the Paicines fault decreases to 4 mm/yr near Bitter.

  2. Catalog of earthquakes along the San Andreas fault system in Central California: January-March, 1972

    USGS Publications Warehouse

    Wesson, R.L.; Bennett, R.E.; Meagher, K.L.

    1973-01-01

    Numerous small earthquakes occur each day in the Coast Ranges of Central California. The detailed study of these earthquakes provides a tool for gaining insight into the tectonic and physical processes responsible for the generation of damaging earthquakes. This catalog contains the fundamental parameters for earthquakes located within and adjacent to the seismograph network operated by the National Center for Earthquake Research (NCER), U.S. Geological Survey, during the period January - March, 1972. The motivation for these detailed studies has been described by Pakiser and others (1969) and by Eaton and others (1970). Similar catalogs of earthquakes for the years 1969, 1970 and 1971 have been prepared by Lee and others (1972 b,c,d). The basic data contained in these catalogs provide a foundation for further studies. This catalog contains data on 1,718 earthquakes in Central California. Of particular interest is a sequence of earthquakes in the Bear Valley area which contained single shocks with local magnitudes of S.O and 4.6. Earthquakes from this sequence make up roughly 66% of the total and are currently the subject of an interpretative study. Arrival times at 118 seismograph stations were used to locate the earthquakes listed in this catalog. Of these, 94 are telemetered stations operated by NCER. Readings from the remaining 24 stations were obtained through the courtesy of the Seismographic Stations, University of California, Berkeley (UCB); the Earthquake Mechanism Laboratory, National Oceanic and Atmospheric Administration, San Francisco (EML); and the California Department of Water Resources, Sacramento. The Seismographic Stations of the University of California, Berkeley,have for many years published a bulletin describing earthquakes in Northern California and the surrounding area, and readings at UCB Stations from more distant events. The purpose of the present catalog is not to replace the UCB Bulletin, but rather to supplement it, by describing the

  3. Catalog of earthquakes along the San Andreas fault system in Central California, April-June 1972

    USGS Publications Warehouse

    Wesson, R.L.; Bennett, R.E.; Lester, F.W.

    1973-01-01

    Numerous small earthquakes occur each day in the coast ranges of Central California. The detailed study of these earthquakes provides a tool for gaining insight into the tectonic and physical processes responsible for the generation of damaging earthquakes. This catalog contains the fundamental parameters for earthquakes located within and adjacent to the seismograph network operated by the National Center for Earthquake Research (NCER), U.S. Geological Survey, during the period April - June, 1972. The motivation for these detailed studies has been described by Pakiser and others (1969) and by Eaton and others (1970). Similar catalogs of earthquakes for the years 1969, 1970 and 1971 have been prepared by Lee and others (1972 b, c, d). A catalog for the first quarter of 1972 has been prepared by Wesson and others (1972). The basic data contained in these catalogs provide a foundation for further studies. This catalog contains data on 910 earthquakes in Central California. A substantial portion of the earthquakes reported in this catalog represents a continuation of the sequence of earthquakes in the Bear Valley area which began in February, 1972 (Wesson and others, 1972). Arrival times at 126 seismograph stations were used to locate the earthquakes listed in this catalog. Of these, 101 are telemetered stations operated by NCER. Readings from the remaining 25 stations were obtained through the courtesy of the Seismographic Stations, University of California, Berkeley (UCB); the Earthquake Mechanism Laboratory, National Oceanic and Atmospheric Administration, San Francisco (EML); and the California Department of Water Resources, Sacramento. The Seismographic Stations of the University of California, Berkeley, have for many years published a bulletin describing earthquakes in Northern California and the surrounding area, and readings at UCB Stations from more distant events. The purpose of the present catalog is not to replace the UCB Bulletin, but rather to supplement

  4. Catalog of earthquakes along the San Andreas fault system in Central California, July-September 1972

    USGS Publications Warehouse

    Wesson, R.L.; Meagher, K.L.; Lester, F.W.

    1973-01-01

    Numerous small earthquakes occur each day in the coast ranges of Central California. The detailed study of these earthquakes provides a tool for gaining insight into the tectonic and physical processes responsible for the generation of damaging earthquakes. This catalog contains the fundamental parameters for earthquakes located within and adjacent to the seismograph network operated by the National Center for Earthquake Research (NCER), U.S. Geological Survey, during the period July - September, 1972. The motivation for these detailed studies has been described by Pakiser and others (1969) and by Eaton and others (1970). Similar catalogs of earthquakes for the years 1969, 1970 and 1971 have been prepared by Lee and others (1972 b, c, d). Catalogs for the first and second quarters of 1972 have been prepared by Wessan and others (1972 a & b). The basic data contained in these catalogs provide a foundation for further studies. This catalog contains data on 1254 earthquakes in Central California. Arrival times at 129 seismograph stations were used to locate the earthquakes listed in this catalog. Of these, 104 are telemetered stations operated by NCER. Readings from the remaining 25 stations were obtained through the courtesy of the Seismographic Stations, University of California, Berkeley (UCB), the Earthquake Mechanism Laboratory, National Oceanic and Atmospheric Administration, San Francisco (EML); and the California Department of Water Resources, Sacramento. The Seismographic Stations of the University of California, Berkeley, have for many years published a bulletin describing earthquakes in Northern California and the surrounding area, and readings at UCB Stations from more distant events. The purpose of the present catalog is not to replace the UCB Bulletin, but rather to supplement it, by describing the seismicity of a portion of central California in much greater detail.

  5. Shifting shoals and shattered rocks : How man has transformed the floor of west-central San Francisco Bay

    USGS Publications Warehouse

    Chin, John L.; Wong, Florence L.; Carlson, Paul R.

    2004-01-01

    subembayments--north bay (San Pablo and Suisun Bays), central bay, and south bay--each characterized by a central area of open water surrounded by intertidal mudflats and marshes. Central bay includes Alcatraz and Angel Islands and also a number of submerged bedrock knobs that protrude through the sediment of the bay floor and rise to within about 40 feet (12 m) of the water surface. The most prominent of these are Harding, Shag, Arch, and Blossom Rocks. These rocks have been lowered by blasting several times in the past, but they remain a potential hazard to shipping because newer cargo vessels are designed with increasingly deeper drafts. Central bay's location adjacent to two major population and commerce centers, San Francisco and Oakland, subjects it to greater human influences than less developed parts of the estuary. The western part of central San Francisco Bay is adjacent to the Golden Gate, the estuary's outlet to the Pacific Ocean. The changing submarine topography of the west-central bay, as well as its geology, form the main focus of this book.

  6. Quality of ground water in agricultural areas of the San Luis Valley, south-central Colorado

    USGS Publications Warehouse

    Edelmann, Patrick; Buckles, D.R.

    1984-01-01

    The quality of ground water in the principal agricultural areas of the San Luis Valley, south-central Colorado was evaluated using chemical analyses of water collected from 57 wells completed in the unconfined aquifer and from 25 wells completed in the confined aquifer. Ground water in both aquifers generally contains dissolved-solids concentrations of less than 500 milligrams per liter. In most areas, calcium is the principal cation in the ground water. Nitrite plus nitrate concentrations expressed as nitrogen, are generally less than 1 milligram per liter. However, the quality of ground water in certain areas may pose health and agricultural hazards. Water in the unconfined aquifer near Center contains high nitrite plus nitrate as nitrogen concentrations. The highest measured concentration in this area was 33 milligrams per liter. Water containing more than 1 milligram per liter of nitrite as nitrogen, or 10 milligrams per liter nitrate, as nitrogen, poses a potential health hazard for infants and should not be used for drinking. In addition, dissolved-solids concentration in the ground water in some areas is greater than 500 milligrams per liter and, if used for irrigation may reduce crop yields. (USGS)

  7. Anomalous hydrogen emissions from the San Andreas fault observed at the Cienega Winery, central California

    USGS Publications Warehouse

    Sato, M.; Sutton, A.J.; McGee, K.A.

    1985-01-01

    We began continuous monitoring of H2 concentration in soil along the San Andreas and Calaveras faults in central California in December 1980, using small H2/O2 fuel-cell sensors. Ten monitoring stations deployed to date have shown that anomalous H2 emissions take place occasionally in addition to diurnal changes. Among the ten sites, the Cienega Winery site has produced data that are characterized by very small diurnal changes, a stable baseline, and remarkably distinct spike-like H2 anomalies since its installation in July 1982. A major peak appeared on 1-10 November 1982, and another on 3 April 1983, and a medium peak on 1 November 1983. The occurrences of these peaks coincided with periods of very low seismicity within a radius of 50 km from the site. In order to methodically assess how these peaks are related to earthquakes, three H2 degassing models were examined. A plausible correlational pattern was obtained by using a model that (1) adopts a hemicircular spreading pattern of H2 along an incipient fracture plane from the hypocenter of an earthquake, (2) relies on the FeO-H2O reaction for H2 generation, and (3) relates the accumulated amount of H2 to the mass of serpentinization of underlying ophiolitic rocks; the mass was tentatively assumed to be proportional to the seismic energy of the earthquake. ?? 1985 Birkha??user Verlag.

  8. Sequence stratigraphy of the Lower Triassic Sinbad Formation, San Rafael Swell, east-central, Utah

    SciTech Connect

    Goodspeed, T.H.; Elrick, M. . Dept. of Earth and Planetary Sciences); Lucas, S.G. )

    1993-04-01

    The Lower Triassic Sinbad Fm (20--30 m thick) in the San Rafael Swell of east-central Utah is high energy carbonate deposits that conformably overlie tidal flat/fluvial channel deposits of the Black Dragon Fm. The Torrey Fm conformably overlies the Sinbad Fm and consists primarily of siliciclastic tidal flat and fluvial deposits. Five facies (in ascending order) are characteristic of the Sinbad Fm: (1) bioturbated calcisiltite with calcite-replaced evaporite nodules and ripple laminations, (2) skeletal-oolitic-intraclastic packstone and grainstone, (3) slightly bioturbated, mechanically laminated, pelletal calcisiltite (5) trough cross-bedded, peloidal to oolitic grainstone, and (5) thin-bedded, skeletal-pelletal-oolitic grainstone with mud to wackestone drapes. Regional facies relationships of the Sinbad Fm indicate initial deepening followed by shallowing. The skeletal-intraclastic packstone and grainstone facies represents maximum flooding. This facies thickens to the northwest and contains an open marine molluscan fauna of ammonites, bivalves, gastropods and scaphopods. The ammonites are indicative of the Tardus Zone of late Smithian age. Deposits above the maximum flooding zone (MFZ) are restricted foreshoal, pelletal calcisiltite, oolitic shoal, and backshoal skeletal-oolitic (with a restricted fauna of molluscs and ostracods) deposits. This shallowing-upward sequence represents the early HST. The Sinbad Fm represents the MFZ and early HST of a 150-m-thick depositional sequence of rocks with the Black Dragon FM representing the TST, and the Torrey Fm representing the late HST.

  9. Evolution of the east-central San Jose del Cabo basin, Baja California Sur, Mexico

    NASA Astrophysics Data System (ADS)

    McTeague, M. S.; Umhoefer, P. J.; Schwennicke, T.; Ingle, J. C.; Cortes Martinez, M.

    2006-12-01

    The San Jose del Cabo basin at the southern tip of the Baja California peninsula records the early tectonic evolution of the west side of the Gulf of California. This study focused on the east central margin of the basin. The basal La Calera Formation unconformably overlies Cretaceous granite and consists of conglomerate, pebbly sandstone and conglomerate, and sandstone deposited in alluvial fans and fan-deltas. Deposition of the La Calera Formation was from ca. 9-14 Ma. The lower member of the Trinidad Formation was deposited beginning ca. 9-13 Ma and consists of sandstone, mudstone, and shelly mudstone deposited in nearshore and estuarine environments. These age estimates are based on sedimentation rates and foraminifera and coccoliths from the NN 11A nannozone (7.4 8.6 Ma, GTS 2004). The middle member of the Trinidad Formation consists of deeper water mudstones deposited by turbidity currents and suspension settling in a shelf to slope and conglomerates deposited by submarine debris flows on the shelf. The basin began earlier than previously thought. The oldest marine rocks are ca.9-13 Ma, while sedimentation on the east side began at ca. 9-14 Ma, synchronous with estimates of initiation of offset on the San Jose del Cabo fault. The Zapote fault is a down-to-the-east normal and sinistral-oblique fault that exposes a wedge of granite and older strata in the footwall to the west. The fault was active during sedimentation in the late Miocene and possibly later. The fault divides the study area into an eastern hanging wall subbasin and western footwall subbasin. The eastern subbasin formed an embayment in the eastern margin of the Cabo basin. A regional flooding surface (ca. 8 Ma) can be correlated across the fault that marks a major marine incursion. Depositional systems evolved rapidly from coarse-grained terrestrial systems to fine-grained marine and estuarine systems. The Cabo basin provides an excellent analogue for comparison with offshore basins, which are

  10. Geology, thermal maturation, and source rock geochemistry in a volcanic covered basin: San Juan sag, south-central Colorado

    USGS Publications Warehouse

    Gries, R.R.; Clayton, J.L.; Leonard, C.

    1997-01-01

    The San Juan sag, concealed by the vast San Juan volcanic field of south-central Colorado, has only recently benefited from oil and gas wildcat drilling and evaluations. Sound geochemical analyses and maturation modeling are essential elements for successful exploration and development. Oil has been produced in minor quantities from an Oligocene sill in the Mancos Shale within the sag, and major oil and gas production occurs from stratigraphically equivalent rocks in the San Juan basin to the south-west and in the Denver basin to the northeast. The objectives of this study were to identify potential source rocks, assess thermal maturity, and determine hydrocarbon-source bed relationships. Source rocks are present in the San Juan sag in the upper and lower Mancos Shale (including the Niobrara Member), which consists of about 666 m (2184 ft) of marine shale with from 0.5 to 3.1 wt. % organic carbon. Pyrolysis yields (S1 + S2 = 2000-6000 ppm) and solvent extraction yields (1000-4000 ppm) indicate that some intervals within the Mancos Shale are good potential source rocks for oil, containing type II organic matter, according to Rock-Eval pyrolysis assay. Oils produced from the San Juan sag and adjacent part of the San Juan basin are geochemically similar to rock extracts obtained from these potential source rock intervals. Based on reconstruction of the geologic history of the basin integrated with models of organic maturation, we conclude that most of the source rock maturation occurred in the Oligocene and Miocene. Little to no maturation took place during Laramide subsidence of the basin, when the Animas and Blanco Basin formations were deposited. The timing of maturation is unlike that of most Laramide basins in the Rocky Mountain region, where maturation occurred as a result of Paleocene and Eocene basin fill. The present geothermal gradient in the San Juan sag is slightly higher (average 3.5??C/100 m; 1.9??F/100 ft) than the regional average for southern Rocky

  11. Creep avalanches on the Central San Andreas Fault: Clues and Causes

    NASA Astrophysics Data System (ADS)

    Khoshmanesh, M.; Shirzaei, M.; Nadeau, R. M.

    2015-12-01

    The Central segment of San Andreas Fault (CSAF) is characterized by a nearly continuous right-lateral aseismic slip. However, observations of the creep rate obtained using Characteristically Repeating Earthquakes (CREs) show a quasi-periodic temporal variation, which is recently confirmed using both InSAR surface deformation time series and geodetic-based time-dependent kinematic model of creep along the CSAF. Here, we show that the statistical analysis of creep fronts along the CSAF indicates a sporadic behavior, signature of a burst-like creep dynamics. Moreover, the probability of creep velocities follows a Gumbel distribution characterized by longer tail toward the extreme positive rates. Fourier analysis of the time series of surface creep rate indicates a self-affine regime with Hurst exponent altering between 0.6 and 0.9 during the observation period of 2003-2011. The variable Hurst component is an indicator for temporal variation in the roughness of the fault zone. To explain the causes of creep avalanches, two possible mechanisms are considered, including temporal variation in: 1) fault geometry, and 2) Ambient normal stress. We find that the overall statistical dependence between the pattern of surface creep rate and the fault geometry is insignificant. To investigate the effect of ambient normal stress, primarily due to variation in pore pressure, we implement a rate and state friction law to link the time-dependent kinematic creep model to the spatiotemporal variations of the normal stress on the velocity-strengthening fault zones. These observations and models help to understand the driving mechanisms that govern the creep rate variations at short spatial length and low velocities. Under these circumstances, the other mechanisms such as thermal pressurization are not feasible.

  12. Selenium volatilization in vegetated agricultural drainage sediment from the San Luis Drain, Central California.

    PubMed

    Bañuelos, G S; Lin, Z-Q; Arroyo, I; Terry, N

    2005-09-01

    The presence of large amounts of Se-laden agricultural drainage sediment in the San Luis Drain, Central California, poses a serious toxic threat to wildlife in the surrounding environment. Effective management of the drainage sediment becomes a practical challenge because the sediment is polluted with high levels of Se, B, and salts. This two-year field study was conducted to identify the best plant species that are salt and B tolerant and that have a superior ability of volatilizing Se from drainage sediment. The drainage sediment was mixed with clean soil, and vegetated with salado alfalfa (Medicago sativa 'salado'), salado grass (Sporobulus airoides 'salado'), saltgrass-turf (Distichlis spp. 'NYPA Turf'), saltgrass-forage (Distichlis spicata (L.) Greene), cordgrass (Spartina patens 'Flageo'), Leucaenia (Leucaena leucocephola), elephant grass (Pennistum purpureum), or wild type-Brassica (Brassica spp.). Results show that elephant grass produced the greatest amount of biomass and accumulated highest concentrations of B. Highest concentrations of Se, S, and Cl were observed in wild-type Brassica. Biogenic volatilization of Se by plants and soil microbes was greater in summer. Among the treatments, the mean daily rates of Se volatilization (microg Se m(-2)d(-1)) were wild-type Brassica (39) > saltgrass-turf (31) > cordgrass (27) > saltgrass forage (24) > elephant grass (22) > salado grass (21) > leucaenia (19) > salado alfalfa (14) > irrigated bare soil (11) > non-irrigated bare soil (6). Overall, rates of Se volatilization in drainage sediment were relatively low due to high levels of sulfate. To manage Se in drainage sediment by phytoremediation, the biological volatilization process needs to be enhanced substantially under field conditions.

  13. Shoreline and Oceano Fault Zones' Intersection Geometry, San Luis Obispo Bay, Offshore South Central Coastal California

    NASA Astrophysics Data System (ADS)

    Hogan, P. J.; Nishenko, S. P.; Greene, H. G.; Bergkamp, B.

    2015-12-01

    As part of the Central Coastal California Seismic Imaging Project, high-resolution 3D low energy marine seismic-reflection data were acquired within San Luis Obispo Bay in 2011 and 2012. Mapping of the sediment-buried bedrock surface using 2D and 3D data clearly reveals that the trace of the Shoreline fault zone bifurcates at Souza Rock. The eastern strand is a reverse fault that trends toward the east-southeast, connecting with the Oceano fault zone onshore. The Shoreline fault is a vertical dextral fault with a very linear geometry that continues south to near the Santa Maria river mouth, and may intersect the Casmalia fault onshore. Both of these fault strands are crossed by Pleistocene low-stand paleochannels eroded into bedrock, and are buried by marine and non-marine sediment. The 3D data show that both the Oceano and Shoreline faults are narrow, well defined fault zones. The reverse slip rate for the Oceano fault (~0.1 mm/y.) falls within published slip rate estimates for the Oceano fault onshore (0.01-0.20 mm/y). The dextral slip rate for the Shoreline fault southeast of Souza Rock is estimated to be 0.06 mm/y. Souza Rock is located on the hanging wall of the Oceano Fault, north of the point of intersection between the Shoreline and Oceano faults. Water depths shoal from 60 m on the surrounding seafloor to 5 m on top of Souza Rock. This structure is interpreted as a structural popup in a restraining bend where the N65°W-trending Oceano fault intersects the N25°W-trending Shoreline fault. The structural geometry near the point of intersection has several minor secondary fault strands, but is remarkably simple.

  14. Spatial variations in slip deficit on the central San Andreas Fault from InSAR

    NASA Astrophysics Data System (ADS)

    Ryder, Isabelle; Bürgmann, Roland

    2008-12-01

    We use ERS InSAR measurements to record spatial variations in creep rate along the creeping segment of the San Andreas Fault (SAF), California, between 1992 and 2001. Inversion of geodetic data yields a slip rate distribution along the creeping segment, which is used for first-order moment release and deficit calculations. We present a time-averaged spatial picture of surface deformation and associated subsurface creep. An interferometric stack is constructed from 12 interferograms that show good coherence. For the decade of observation, the total right-lateral offset spanned by the data is ~34 mmyr-1. Along most of the length of the creeping segment, this offset occurs within a narrow (<2 km) zone close to the fault trace. In the northern part, a minor part of the offset is taken up by the nearby Calaveras-Paicines Fault. In general, the observed rates of surface creep are consistent with those obtained by several other studies for a longer and/or earlier period of time, using different geodetic methods. This suggests that the average creep rate has been constant over a period of almost four decades. A joint GPS-InSAR inversion implies that the shallow creep rate is variable along strike, reaching up to 31.5 +/- 1 mmyr-1 in the central section of the creeping segment, tapering off along-strike to the south and becoming partitioned across two subparallel faults in the north. The deep slip rate beneath the seismogenic layer is 33 +/- 3 mmyr-1. The difference between shallow and deep slip rates suggests that there is a shallow slip deficit on the creeping segment of the SAF (CSAF). Moment release rate due to aseismic slip is approximately three orders of magnitude greater than seismic moment release. The annual creep on the CSAF is equivalent to the moment released in a M 6 earthquake. The equivalent moment of the slip deficit relative to the deep slip rate is between 4.1 × 1017 and 8.4 × 1017 N myr-1, which is equivalent to a magnitude 5.7-5.9 earthquake. Over a

  15. Monitoring of hydrogen along the San Andreas and Calaveras faults in central California in 1980-1984

    NASA Astrophysics Data System (ADS)

    Sato, Motoaki; Sutton, A. J.; McGee, K. A.; Russell-Robinson, Susan

    1986-11-01

    Hydrogen (H2) has been monitored continuously at 1.5-m depth at nine sites along the San Andreas and Calaveras faults in central California since December 1980. Site characteristic small noninstrumental diurnal variations were recorded during quiescent periods at most sites. Abrupt H2 changes were observed concurrently at two sites on the Calaveras fault; some of these were correlated with oscillatory fault slips. Large (1000-4000 ppm) H2 increases were recorded at some sites on the San Andreas fault between July 1982 and November 1983, which may be correlated with eleven M ≥ 5 earthquakes that occurred near Coalinga during this period. We attribute both the H2 increases and the triggering of the earthquakes to a large-scale compressive stress field within the ductile mafic crust near the plate boundary. The stress perhaps caused bulging of the base of the brittle upper crust and thus caused dilation of the San Andreas fault zone, allowing the escape of pent-up H2 generated by hydration reaction of the mafic crust. At the same time, mobile serpentinites may have squeezed into the seismogenic fault beneath the Coalinga area triggering the earthquakes.

  16. Pliocene and Pleistocene geologic and climatic evolution in the San Luis Valley of south-central Colorado

    USGS Publications Warehouse

    Rogers, K.L.; Larson, E.E.; Smith, G.; Katzman, D.; Smith, G.R.; Cerling, T.; Wang, Y.; Baker, R.G.; Lohmann, K.C.; Repenning, C.A.; Patterson, P.; Mackie, G.

    1992-01-01

    Sediments of the Alamosa Formation spanning the upper part of the Gauss and most of the Matuyama Chrons were recovered by coring in the high (2300 m) San Luis Valley of south-central Colorado. The study site is located at the northern end of the Rio Grande rift. Lithologic changes in the core sediments provide evidence of events leading to integration of the San Luis drainage basin into the Rio Grande. The section, which includes the Huckleberry Ridge Ash (2.02 Ma) and spans the entire Matuyama Chron, contains pollen, and invertebrate and vertebrate fossils. Stable isotope analyses of inorganic and biogenic carbonate taken over most of the core indicate substantially warmer temperatures than occur today in the San Luis Valley. At the end of the Olduvai Subchron, summer precipitation decreased, summer pan evaporation increased, and temperatures increased slightly compared to the earlier climate represented in the core. By the end of the Jaramillo Subchron, however, cold/wet and warm/dry cycles become evident and continue into the cold/wet regime associated with the deep-sea oxygen-isotope Stage 22 glaciation previously determined from outcrops at the same locality. Correspondence between the Hansen Bluff climatic record and the deep-sea oxygen-isotope record (oxygen-isotope stages from about 110-18) is apparent, indicating that climate at Hansen Bluff was responding to global climatic changes. ?? 1992.

  17. Tomographic Rayleigh wave group velocities in the Central Valley, California, centered on the Sacramento/San Joaquin Delta

    NASA Astrophysics Data System (ADS)

    Fletcher, Jon B.; Erdem, Jemile; Seats, Kevin; Lawrence, Jesse

    2016-04-01

    If shaking from a local or regional earthquake in the San Francisco Bay region were to rupture levees in the Sacramento/San Joaquin Delta, then brackish water from San Francisco Bay would contaminate the water in the Delta: the source of freshwater for about half of California. As a prelude to a full shear-wave velocity model that can be used in computer simulations and further seismic hazard analysis, we report on the use of ambient noise tomography to build a fundamental mode, Rayleigh wave group velocity model for the region around the Sacramento/San Joaquin Delta in the western Central Valley, California. Recordings from the vertical component of about 31 stations were processed to compute the spatial distribution of Rayleigh wave group velocities. Complex coherency between pairs of stations was stacked over 8 months to more than a year. Dispersion curves were determined from 4 to about 18 s. We calculated average group velocities for each period and inverted for deviations from the average for a matrix of cells that covered the study area. Smoothing using the first difference is applied. Cells of the model were about 5.6 km in either dimension. Checkerboard tests of resolution, which are dependent on station density, suggest that the resolving ability of the array is reasonably good within the middle of the array with resolution between 0.2 and 0.4°. Overall, low velocities in the middle of each image reflect the deeper sedimentary syncline in the Central Valley. In detail, the model shows several centers of low velocity that may be associated with gross geologic features such as faulting along the western margin of the Central Valley, oil and gas reservoirs, and large crosscutting features like the Stockton arch. At shorter periods around 5.5 s, the model's western boundary between low and high velocities closely follows regional fault geometry and the edge of a residual isostatic gravity low. In the eastern part of the valley, the boundaries of the low

  18. Correlation between deep fluids, tremor and creep along the central San Andreas fault.

    PubMed

    Becken, Michael; Ritter, Oliver; Bedrosian, Paul A; Weckmann, Ute

    2011-12-01

    The seismicity pattern along the San Andreas fault near Parkfield and Cholame, California, varies distinctly over a length of only fifty kilometres. Within the brittle crust, the presence of frictionally weak minerals, fault-weakening high fluid pressures and chemical weakening are considered possible causes of an anomalously weak fault northwest of Parkfield. Non-volcanic tremor from lower-crustal and upper-mantle depths is most pronounced about thirty kilometres southeast of Parkfield and is thought to be associated with high pore-fluid pressures at depth. Here we present geophysical evidence of fluids migrating into the creeping section of the San Andreas fault that seem to originate in the region of the uppermost mantle that also stimulates tremor, and evidence that along-strike variations in tremor activity and amplitude are related to strength variations in the lower crust and upper mantle. Interconnected fluids can explain a deep zone of anomalously low electrical resistivity that has been imaged by magnetotelluric data southwest of the Parkfield-Cholame segment. Near Cholame, where fluids seem to be trapped below a high-resistivity cap, tremor concentrates adjacent to the inferred fluids within a mechanically strong zone of high resistivity. By contrast, subvertical zones of low resistivity breach the entire crust near the drill hole of the San Andreas Fault Observatory at Depth, northwest of Parkfield, and imply pathways for deep fluids into the eastern fault block, coincident with a mechanically weak crust and the lower tremor amplitudes in the lower crust. Fluid influx to the fault system is consistent with hypotheses of fault-weakening high fluid pressures in the brittle crust. PMID:22129729

  19. Correlation between deep fluids, tremor and creep along the central San Andreas fault

    USGS Publications Warehouse

    Becken, M.; Ritter, O.; Bedrosian, P.A.; Weckmann, U.

    2011-01-01

    The seismicity pattern along the San Andreas fault near Parkfield and Cholame, California, varies distinctly over a length of only fifty kilometres. Within the brittle crust, the presence of frictionally weak minerals, fault-weakening high fluid pressures and chemical weakening are considered possible causes of an anomalously weak fault northwest of Parkfield. Non-volcanic tremor from lower-crustal and upper-mantle depths is most pronounced about thirty kilometres southeast of Parkfield and is thought to be associated with high pore-fluid pressures at depth. Here we present geophysical evidence of fluids migrating into the creeping section of the San Andreas fault that seem to originate in the region of the uppermost mantle that also stimulates tremor, and evidence that along-strike variations in tremor activity and amplitude are related to strength variations in the lower crust and upper mantle. Interconnected fluids can explain a deep zone of anomalously low electrical resistivity that has been imaged by magnetotelluric data southwest of the Parkfield-Cholame segment. Near Cholame, where fluids seem to be trapped below a high-resistivity cap, tremor concentrates adjacent to the inferred fluids within a mechanically strong zone of high resistivity. By contrast, subvertical zones of low resistivity breach the entire crust near the drill hole of the San Andreas Fault Observatory at Depth, northwest of Parkfield, and imply pathways for deep fluids into the eastern fault block, coincident with a mechanically weak crust and the lower tremor amplitudes in the lower crust. Fluid influx to the fault system is consistent with hypotheses of fault-weakening high fluid pressures in the brittle crust. ?? 2011 Macmillan Publishers Limited. All rights reserved.

  20. Correlation between deep fluids, tremor and creep along the central San Andreas fault.

    PubMed

    Becken, Michael; Ritter, Oliver; Bedrosian, Paul A; Weckmann, Ute

    2011-11-30

    The seismicity pattern along the San Andreas fault near Parkfield and Cholame, California, varies distinctly over a length of only fifty kilometres. Within the brittle crust, the presence of frictionally weak minerals, fault-weakening high fluid pressures and chemical weakening are considered possible causes of an anomalously weak fault northwest of Parkfield. Non-volcanic tremor from lower-crustal and upper-mantle depths is most pronounced about thirty kilometres southeast of Parkfield and is thought to be associated with high pore-fluid pressures at depth. Here we present geophysical evidence of fluids migrating into the creeping section of the San Andreas fault that seem to originate in the region of the uppermost mantle that also stimulates tremor, and evidence that along-strike variations in tremor activity and amplitude are related to strength variations in the lower crust and upper mantle. Interconnected fluids can explain a deep zone of anomalously low electrical resistivity that has been imaged by magnetotelluric data southwest of the Parkfield-Cholame segment. Near Cholame, where fluids seem to be trapped below a high-resistivity cap, tremor concentrates adjacent to the inferred fluids within a mechanically strong zone of high resistivity. By contrast, subvertical zones of low resistivity breach the entire crust near the drill hole of the San Andreas Fault Observatory at Depth, northwest of Parkfield, and imply pathways for deep fluids into the eastern fault block, coincident with a mechanically weak crust and the lower tremor amplitudes in the lower crust. Fluid influx to the fault system is consistent with hypotheses of fault-weakening high fluid pressures in the brittle crust.

  1. Paleobathymetric maps of tertiary La Honda Basin and implications for offset along San Andreas fault in central California

    SciTech Connect

    Stanley, R.G.

    1987-05-01

    Paleobathymetric maps of the La Honda basin of central California were constructed for ten intervals of geologic time from late Paleocene (Nezian) to middle Miocene (Luisian). The maps are based on analyses of benthic foraminiferal biofacies in more than 800 faunal lists compiled from the literature and from subsurface data provided by oil companies. The sequence of paleobathymetric maps shows the paleogeographic evolution of the La Honda basin. From the late Paleocene (Ynezian) to the early Oligocene (early Zemorrian), deep-sea sands and muds accumulated at water depths of 2000 m and more on a surface that sloped gently to the north and northeast. Striking changes in the configuration of the La Honda basin occurred during the late Oligocene and early Miocene (late Zemorrian). Much of the basin floor remained at water depths of 2000 m and greater, but submarine volcanic rocks locally built up to form seamounts, and movement along the Zayante-Vergeles fault led to shoaling and development of a narrow shelf and very steep slope along the southwestern margin of the basin. During the early and middle Miocene (Relizian and Luisian), the entire basin shoaled to depths of less than 1500 m. Comparison of paleobathymetric maps of the La Honda and San Joaquin basins lends support to the notion that the two basins were once contiguous but have been separated by about 320 to 330 km of right-lateral displacement along the San Andreas fault since the earliest Miocene (late Zemorrian and Saucesian).

  2. Crustal structure of a transform plate boundary: San Francisco Bay and the central California continental margin

    USGS Publications Warehouse

    Holbrook, W.S.; Brocher, T.M.; ten Brink, U.S.; Hole, J.A.

    1996-01-01

    Wide-angle seismic data collected during the Bay Area Seismic Imaging Experiment provide new glimpses of the deep structure of the San Francisco Bay Area Block and across the offshore continental margin. San Francisco Bay is underlain by a veneer (<300 m) of sediments, beneath which P wave velocities increase rapidly from 5.2 km/s to 6.0 km/s at 7 km depth, consistent with rocks of the Franciscan subduction assemblage. The base of the Franciscan at-15-18 km depth is marked by a strong wide-angle reflector, beneath which lies an 8- to 10-km-thick lower crust with an average velocity of 6.75??0.15 km/s. The lower crust of the Bay Area Block may be oceanic in origin, but its structure and reflectivity indicate that it has been modified by shearing and/or magmatic intrusion. Wide-angle reflections define two layers within the lower crust, with velocities of 6.4-6.6 km/s and 6.9-7.3 km/s. Prominent subhorizontal reflectivity observed at near-vertical incidence resides principally in the lowermost layer, the top of which corresponds to the "6-s reflector" of Brocher et al. [1994]. Rheological modeling suggests that the lower crust beneath the 6-s reflector is the weakest part of the lithosphere; the horizontal shear zone suggested by Furlong et al. [1989] to link the San Andreas and Hayward/Calaveras fault systems may actually be a broad zone of shear deformation occupying the lowermost crust. A transect across the continental margin from the paleotrench to the Hayward fault shows a deep crustal structure that is more complex than previously realized. Strong lateral variability in seismic velocity and wide-angle reflectivity suggests that crustal composition changes across major transcurrent fault systems. Pacific oceanic crust extends 40-50 km landward of the paleotrench but, contrary to prior models, probably does not continue beneath the Salinian Block, a Cretaceous arc complex that lies west of the San Andreas fault in the Bay Area. The thickness (10 km) and high

  3. Database compilation for the geologic map of the San Francisco volcanic field, north-central Arizona

    USGS Publications Warehouse

    Bard, Joseph A.; Ramsey, David W.; Wolfe, Edward W.; Ulrich, George E.; Newhall, Christopher G.; Moore, Richard B.; Bailey, Norman G.; Holm, Richard F.

    2016-01-08

    The orignial geologic maps were prepared under the Geothermal Research Program of the U.S. Geological Survey as a basis for interpreting the history of magmatic activity in the volcanic field. The San Francisco field, which is largely Pleistocene in age, is in northern Arizona, just north of the broad transition zone between the Colorado Plateau and the Basin and Range province. It is one of several dominantly basaltic volcanic fields of the late Cenozoic age situated near the margin of the Colorado Plateau. The volcanic field contains rocks ranging in composition from basalt to rhyolite—the products of eruption through Precambrian basement rocks and approximately a kilometer of overlying, nearly horizontal, Paleozoic and Mesozoic sedimentary rocks. About 500 km3 of erupted rocks cover about 5,000 km2 of predominantly Permian and locally preserved Triassic sedimentary rocks that form the erosionally stripped surface of the Colorado Plateau in Northern Arizona.

  4. Database compilation for the geologic map of the San Francisco volcanic field, north-central Arizona

    USGS Publications Warehouse

    Bard, Joseph A.; Ramsey, David W.; Wolfe, Edward W.; Ulrich, George E.; Newhall, Christopher G.; Moore, Richard B.; Bailey, Norman G.; Holm, Richard F.

    2015-01-01

    The orignial geologic maps were prepared under the Geothermal Research Program of the U.S. Geological Survey as a basis for interpreting the history of magmatic activity in the volcanic field. The San Francisco field, which is largely Pleistocene in age, is in northern Arizona, just north of the broad transition zone between the Colorado Plateau and the Basin and Range province. It is one of several dominantly basaltic volcanic fields of the late Cenozoic age situated near the margin of the Colorado Plateau. The volcanic field contains rocks ranging in composition from basalt to rhyolite—the products of eruption through Precambrian basement rocks and approximately a kilometer of overlying, nearly horizontal, Paleozoic and Mesozoic sedimentary rocks. About 500 km3 of erupted rocks cover about 5,000 km2 of predominantly Permian and locally preserved Triassic sedimentary rocks that form the erosionally stripped surface of the Colorado Plateau in Northern Arizona.

  5. Quaternary crustal deformation along a major branch of the San Andreas fault in central California

    USGS Publications Warehouse

    Weber, G.E.; Lajoie, K.R.; Wehmiller, J. F.

    1979-01-01

    Deformed marine terraces and alluvial deposits record Quaternary crustal deformation along segments of a major, seismically active branch of the San Andreas fault which extends 190 km SSE roughly parallel to the California coastline from Bolinas Lagoon to the Point Sur area. Most of this complex fault zone lies offshore (mapped by others using acoustical techniques), but a 4-km segment (Seal Cove fault) near Half Moon Bay and a 26-km segment (San Gregorio fault) between San Gregorio and Point Ano Nuevo lie onshore. At Half Moon Bay, right-lateral slip and N-S horizontal compression are expressed by a broad, synclinal warp in the first (lowest: 125 ka?) and second marine terraces on the NE side of the Seal Cove fault. This structure plunges to the west at an oblique angle into the fault plane. Linear, joint0controlled stream courses draining the coastal uplands are deflected toward the topographic depression along the synclinal axis where they emerge from the hills to cross the lowest terrace. Streams crossing the downwarped part of this terrace adjacent to Half Moon Bay are depositing alluvial fans, whereas streams crossing the uplifted southern limb of the syncline southwest of the bay are deeply incised. Minimum crustal shortening across this syncline parallel to the fault is 0.7% over the past 125 ka, based on deformation of the shoreline angle of the first terrace. Between San Gregorio and Point Ano Nuevo the entire fault zone is 2.5-3.0 km wide and has three primary traces or zones of faulting consisting of numerous en-echelon and anastomozing secondary fault traces. Lateral discontinuities and variable deformation of well-preserved marine terrace sequences help define major structural blocks and document differential motions in this area and south to Santa Cruz. Vertical displacement occurs on all of the fault traces, but is small compared to horizontal displacement. Some blocks within the fault zone are intensely faulted and steeply tilted. One major block 0

  6. Potential of public lands in California's central valley as habitat for the endangered San Joaquin kit fox. [Vulpes macrotis mutica

    SciTech Connect

    O'Farrell, T.P.; McCue, P.; Sauls, M.L.; Kato, T.

    1982-01-01

    As part of an assessment of the impacts of their activities on the endangered San Joaquin kit fox and its essential habitat, the Department of Energy and Bureau of Land Management investigated the potential of public lands in the San Joaquin Valley as suitable habitat for the San Joaquin kit fox. (ACR)

  7. Retardations in fault creep rates before local moderate earthquakes along the San Andreas fault system, central California

    USGS Publications Warehouse

    Burford, R.O.

    1988-01-01

    Records of shallow aseismic slip (fault creep) obtained along parts of the San Andreas and Calaveras faults in central California demonstrate that significant changes in creep rates often have been associated with local moderate earthquakes. An immediate postearthquake increase followed by gradual, long-term decay back to a previous background rate is generally the most obvious earthquake effect on fault creep. This phenomenon, identified as aseismic afterslip, usually is characterized by above-average creep rates for several months to a few years. In several cases, minor step-like movements, called coseismic slip events, have occurred at or near the times of mainshocks. One extreme case of coseismic slip, recorded at Cienega Winery on the San Andreas fault 17.5 km southeast of San Juan Bautista, consisted of 11 mm of sudden displacement coincident with earthquakes of ML=5.3 and ML=5.2 that occurred 2.5 minutes apart on 9 April 1961. At least one of these shocks originated on the main fault beneath the winery. Creep activity subsequently stopped at the winery for 19 months, then gradually returned to a nearly steady rate slightly below the previous long-term average. The phenomena mentioned above can be explained in terms of simple models consisting of relatively weak material along shallow reaches of the fault responding to changes in load imposed by sudden slip within the underlying seismogenic zone. In addition to coseismic slip and afterslip phenomena, however, pre-earthquake retardations in creep rates also have been observed. Onsets of significant, persistent decreases in creep rates have occurred at several sites 12 months or more before the times of moderate earthquakes. A 44-month retardation before the 1979 ML=5.9 Coyote Lake earthquake on the Calaveras fault was recorded at the Shore Road creepmeter site 10 km northwest of Hollister. Creep retardation on the San Andreas fault near San Juan Bautista has been evident in records from one creepmeter site for

  8. San Ignacio (La Tembladera) geothermal site, Departamento de Francisco Morazan, Honduras, Central America: Geological field report

    SciTech Connect

    Aldrich, M.J.; Eppler, D.; Heiken, G.; Flores, W.; Ramos, N.; Ritchie, A.

    1987-06-01

    The San Ignacio (La Tembladera) geothermal site is located on the north side of the Siria Valley, Departamento de Francisco Morazan, near the village of Barrosa. Hot springs are located along a northwest-trending fault scarp at the edge of the valley and along north-trending faults that cross the scarp. The rocks in the area are primarily Paleozoic metamorphic rocks, overlain by patches of Tertiary Padre Miguel Group tuffs and alluvial deposits. Movement probably occurred along several faults during latest Tertiary and possibly early Quaternary times. Four spring areas were mapped. Area 1, the largest, is associated with a sinter mound and consists of 40 spring groups. About half of the springs, aligned along a north-south trend, are boiling. Area 2 is a small sinter mound with several seeps. Area 3 consists of a group of hot and boiling springs aligned along a north-trending fault. The springs rise through fractured schists and a thin cover of alluvium. Area 4 is located at the intersection of several faults and includes one of the largest boiling springs in the area.

  9. Comparison of sediment supply to San Francisco Bay from watersheds draining the Bay Area and the Central Valley of California

    USGS Publications Warehouse

    McKee, L.J.; Lewicki, M.; Schoellhamer, D.H.; Ganju, N.K.

    2013-01-01

    Quantifying suspended sediment loads is important for managing the world's estuaries in the context of navigation, pollutant transport, wetland restoration, and coastal erosion. To address these needs, a comprehensive analysis was completed on sediment supply to San Francisco Bay from fluvial sources. Suspended sediment, optical backscatter, velocity data near the head of the estuary, and discharge data obtained from the output of a water balance model were used to generate continuous suspended sediment concentration records and compute loads to the Bay from the large Central Valley watershed. Sediment loads from small tributary watersheds around the Bay were determined using 235 station-years of suspended sediment data from 38 watershed locations, regression analysis, and simple modeling. Over 16 years, net annual suspended sediment load to the head of the estuary from its 154,000 km2 Central Valley watershed varied from 0.13 to 2.58 (mean = 0.89) million metric t of suspended sediment, or an average yield of 11 metric t/km2/yr. Small tributaries, totaling 8145 km2, in the nine-county Bay Area discharged between 0.081 and 4.27 (mean = 1.39) million metric t with a mean yield of 212 metric t/km2/yr. The results indicate that the hundreds of urbanized and tectonically active tributaries adjacent to the Bay, which together account for just 5% of the total watershed area draining to the Bay and provide just 7% of the annual average fluvial flow, supply 61% of the suspended sediment. The small tributary loads are more variable (53-fold between years compared to 21-fold for the inland Central Valley rivers) and dominated fluvial sediment supply to the Bay during 10 out of 16 yr. If San Francisco Bay is typical of other estuaries in active tectonic or climatically variable coastal regimes, managers responsible for water quality, dredging and reusing sediment accumulating in shipping channels, or restoring wetlands in the world's estuaries may need to more carefully

  10. Aseismic slip and fault-normal strain along the central creeping section of the San Andreas fault

    USGS Publications Warehouse

    Rolandone, F.; Burgmann, R.; Agnew, D.C.; Johanson, I.A.; Templeton, D.C.; d'Alessio, M. A.; Titus, S.J.; DeMets, C.; Tikoff, B.

    2008-01-01

    We use GPS data to measure the aseismic slip along the central San Andreas fault (CSAF) and the deformation across adjacent faults. Comparison of EDM and GPS data sets implies that, except for small-scale transients, the fault motion has been steady over the last 40 years. We add 42 new GPS, velocities along the CSAF to constrain the regional strain distribution. Shear strain rates are less than 0.083 ?? 0.010 ??strain/yr adjacent to the creeping SAF, with 1-4.5 mm/yr of contraction across the Coast Ranges. Dislocation modeling of the data gives a deep, long-term slip rate of 31-35 mm/yr and a shallow (0-12 km) creep rate of 28 mm/yr along the central portion of the CSAF, consistent with surface creep measurements. The lower shallow slip rate may be due to the effect of partial locking along the CSAF or reflect reduced creep rates late in the earthquake cycle of the adjoining SAF rupture zones. Copyright 2008 by the American Geophysical Union.

  11. Aseismic slip and fault-normal strain along the central creeping section of the San Andreas fault

    NASA Astrophysics Data System (ADS)

    Rolandone, F.; Bürgmann, R.; Agnew, D. C.; Johanson, I. A.; Templeton, D. C.; d'Alessio, M. A.; Titus, S. J.; DeMets, C.; Tikoff, B.

    2008-07-01

    We use GPS data to measure the aseismic slip along the central San Andreas fault (CSAF) and the deformation across adjacent faults. Comparison of EDM and GPS data sets implies that, except for small-scale transients, the fault motion has been steady over the last 40 years. We add 42 new GPS velocities along the CSAF to constrain the regional strain distribution. Shear strain rates are less than 0.083 +/- 0.010 μstrain/yr adjacent to the creeping SAF, with 1-4.5 mm/yr of contraction across the Coast Ranges. Dislocation modeling of the data gives a deep, long-term slip rate of 31-35 mm/yr and a shallow (0-12 km) creep rate of 28 mm/yr along the central portion of the CSAF, consistent with surface creep measurements. The lower shallow slip rate may be due to the effect of partial locking along the CSAF or reflect reduced creep rates late in the earthquake cycle of the adjoining SAF rupture zones.

  12. Aftershock asymmetry/rupture directivity among central San Andreas fault microearthquakes

    NASA Astrophysics Data System (ADS)

    Rubin, Allan M.; Gillard, Dominique

    2000-08-01

    Using a waveform cross-correlation technique, we have obtained precise relative locations for nearly 75% of the Northern California Seismic Network catalog (4300 earthquakes) occurring between 1984 and 1997 along 50 km of the San Andreas fault. Errors in relative location are meters to tens of meters for events separated by tens to hundreds of meters. We find that consecutive earthquakes in the relocated catalog occur no closer than a distance approximately equal to the radius of the first rupture, as estimated from the moment-magnitude relationship of Abercrombie [1996] assuming a 10-MPa stress drop. When the relative position vectors between consecutive events are normalized by this distance and projected onto the fault surface, they define a hole whose shape suggests that typical microearthquakes are elongate in the mode II (slip-parallel) direction by several tens of percent. Moreover, of the 100 immediate aftershocks occurring closest to the mode II edges of the prior rupture, more than twice as many occur to the northwest than to the southeast. We interpret this asymmetry as resulting from the large contrast in material properties across the fault. Models of dynamic rupture between dissimilar media predict that ruptures in this region may run preferentially to the southeast, in the direction of motion of the lower-velocity material. If so, then the barriers that stop rupture fronts moving to the southeast should initially be farther from failure, on average, than the barriers that stop rupture fronts moving to the northwest. Once the rupture stops, the induced stress change is more symmetric but the fault remains farther from failure (on average) to the southeast. This interpretation receives some support from pulse width measurements on a localized set of 72 magnitude 0.6 to 3.6 earthquakes.

  13. Tectonic framework of the Parkfield-Cholame area, central San Andreas fault zone, California

    SciTech Connect

    Sims, J.D.; Ross, D.C.; Irwin, W.P.

    1985-01-01

    Recent geologic mapping of the NW-trending San Andreas fault zone (SAFZ) in the southern Diablo Range reveals details of this structurally complex region. Movement on the fault juxtaposes dissimilar tectonic terranes. The region on the NE side is characterized by complexly folded and faulted rocks of the Franciscan assemblage, the Coast Range ophiolite, and sedimentary rocks of the Great Valley sequence and younger formations. The region on the SW side is characterized by crystalline basement rocks of the Salinia terrane overlain by slightly deformed Pliocene and Pleistocene gravel and Miocene and Pliocene sedimentary rocks. The active trace of the SAFZ is along the SW side of a belt of melange that separates the Salinia terrane from the terranes to the NE. The active main trace is notable for a right step over of about 1 km in the southern part of the area and a 5/sup 0/ left bend in the northern part of the area. The melange consists of highly sheared and deformed rocks of late Cenozoic units, and exotic blocks of granite, gabbro, and marble. Deformation of Late Cretaceous and younger rocks east of the SAFZ varies with their age as follows: 1) Late Cretaceous rocks are strongly deformed and overlain by late Cenozoic rocks with angular unconformity, 2) early(.) and middle Miocene rocks are the most complexly folded, 3) late Miocene and early Pliocene strata are less complexly deformed, and 4) Pliocene and Pleistocene rocks the least deformed. Folding resulted from north-south compression across the SAFZ since early (.) Miocene time.

  14. Geochemistry of the Mesozoic bedded cherts of Central Baja California (Vizcaino-Cedros-San Benito): implications for paleogeographic reconstruction of an old oceanic basin

    NASA Astrophysics Data System (ADS)

    Rangin, Claude; Steinberg, Michel; Bonnot-Courtois, Chantal

    1981-07-01

    In central Baja California (Vizcaino Peninsula, and Cedros and San Benito Islands) two distinct radiolarian bedded chert sequences of late Triassic and late Jurassic/lowermost Cretaceous age, can be differentiated on lithostratigraphic and geochemical criteria. These bedded chert sequences are part of the conformable sedimentary cover of more or less dismembered ophiolites, which are overthrusted by the San Andrès-Cedros volcanic arc system of middle late Jurassic age. Major and trace elements permit paleogeographic zonation of the late Jurassic/lowermost Cretaceous radiolarites lying conformably upon ophiolites considered as fragments of an oceanic basin floor which developed westward of the San Andrès volcanic arc. Progressive accretion of this oceanic basin floor, along the continental margin is supported by the fact that the more distal radiolarian chert sequences belong to the lowermost structural units of this area.

  15. High-resolution electromagnetic imaging of the San Andreas fault in Central California

    SciTech Connect

    Unsworth, M.; Egbert, G.; Booker, J.

    1999-01-01

    Although there is increasing evidence that fluids may play a significant role in the earthquake rupture process, direct observation of fluids in active fault zones remains difficult. Since the presence of an electrically conducting fluid, such as saline pore water, strongly influences the overall conductivity of crustal rocks, electrical and electromagnetic methods offer great potential for overcoming this difficulty. Here we present and compare results from high-resolution magnetotelluric (MT) profiles across two segments of the San Andreas Fault (SAF) which exhibit very different patterns of seismicity: Parkfield, which has regular small earthquakes and creep events, and in the Carrizo Plain, where the fault is seismically quiescent and apparently locked. In both surveys, electric fields were sampled continuously, with 100 m long dipoles laid end-to-end across the fault. From 100 to 0.1 Hz the data from both profiles are consistent with a two-dimensional (2-D) fault-parallel resistivity model. When both transverse electric and magnetic (TE and TM) mode data are included in the interpretation, narrow ({approximately}300{endash}600 m wide) zones of low resistivity extending to depths of 2{endash}4 km in the core of the fault are required at both locations. However, at Parkfield the conductance (conductivity thickness product) of the anomalous region is an order of magnitude larger than at Carrizo Plain, suggesting much higher concentrations of fluids for the more seismically active Parkfield segment. We also image structural differences between the two segments. At Carrizo Plain, resistive, presumably crystalline, rocks are present on both sides of the fault at depths below 3{endash}4 km. In particular, we clearly image resistive basement extending {approximately}10 km or more east of the SAF, beneath the Elkhorn Hills and Temblor Range. At Parkfield the situation is quite different with a resistive block of Salinian granite west of the fault and an electrically

  16. Zongo-San Gaban zone: Eocene foreland boundary of the Central Andean orogen, northwest Bolivia and southeast Peru

    SciTech Connect

    Farrar, E.; Clark, A.H.; Kontak, D.J.; Archibald, D.A.

    1988-01-01

    Discordant muscovite and biotite K-Ar dates of samples taken in six transects through the Cordillera Oriental of southeast Peru and northwest Bolivia, combined with /sup 40/Ar//sup 39/Ar age spectra, reveal a northwest-trending, structurally cryptic, tectonothermal zone of late Eocene age (ca. 38 Ma) that overprints Triassic and older igneous and metamorphic rocks. The zone is at least 450 km long but is less than 25 km wide; temperatures along its northeast boundary are estimated to have reached 350/sup 0/C. No Paleogene magmatism has been recognized that could account for the thermal resetting of the K-Ar isotopic system. Uplift, erosion, and southwest-verging thrusting accompanied the development of this domain, which defined the foreland boundary of the orogen prior to inception of northeast-verging Andean thrusting in Miocene time. It is proposed that this tectonothermal zone, the Zongo-San Gaban zone (ZSGZ), which involves thrusting and basement shortening, is the southerly manifestation of the Incaic compressional deformation, which produced the thin-skinned Maranon thrust and fold belt (MTFB) north of the Abancay deflection of central Peru.

  17. Imaging fault slip variation along the central San Andreas fault from satellite, airborne InSAR and GPS

    NASA Astrophysics Data System (ADS)

    Liu, Z.; Lundgren, P.; Fielding, E. J.; Hensley, S.

    2011-12-01

    The improved spatiotemporal resolution of surface deformation from recent satellite and airborne InSAR measurements provides great potential to improve our understanding of faulting processes and earthquake hazard for a given fault system. A major plate boundary fault in central California, the central San Andreas fault (CSAF) displays a spectrum of complex fault slip behaviors with creeping in its central segment that decreases towards its northwest and southeast ends where the fault transitions to being locked. In the north the CSAF branches into two sub-parallel faults that are both actively accommodating plate motion. To the south, near the Parkfield transition, large earthquakes have occurred with at least six Mw ~6.0 events since 1857, most recently in 2004. To understand the complexity and variety of fault slip behaviors and fault mechanics, we integrate satellite and airborne synthetic aperture radar (SAR) repeat pass interferometry (RPI) observations, with GPS measurements from the Plate Boundary Observatory (PBO) and regional campaign networks to estimate fault slip and shallow slip deficits along the CSAF. Existing C-band ERS-1/2, Envisat and Radarsat SAR data provide long archives of SAR data over the region but are subject to severe decorrelation. The Japan Aerospace Exploration Agency's ALOS satellite has made less frequent acquisitions (5-6/yr per track) since 2006 but its PALSAR L-band sensor provides much improved coherence compared to shorter wavelength radar data. More recently, the NASA UAVSAR airborne SAR has repeated fault perpendicular adjacent swaths imaged from opposing look directions and fault parallel swath flights over the CSAF over the past three years and provides an improved imaging of fault slip related deformation at finer spatial resolution than previous platforms (~6m at 12 azimuth x 3 range looks). Compared to C-band instruments, the UAVSAR provides nearly complete spatial coverage. Compared to the ALOS mission, the UAVSAR

  18. Forward and Reverse Modeling Compressive Deformation in a 3D Geologic Model along the Central San Andreas Fault Zone

    NASA Astrophysics Data System (ADS)

    Roberts, M. A.; Graymer, R. W.; McPhee, D.

    2015-12-01

    During the late Miocene, a small change in the relative motion of the Pacific plate resulted in compressive as well as translational deformation along the central San Andreas Fault (SAF), creating thrust faults and folds throughout this region of California. We constructed a 3D model of an upper crustal volume between Pinnacles National Park and Gold Hill by assembling geologic map data and cross sections, geophysical data, and petroleum well logs in MoveTm, software which has the ability to forward and reverse model movement along faults and folds. For this study, we chose a blind thrust fault west of the SAF near Parkfield to compare deformation produced by MoveTm's forward modeling algorithm with that observed. We chose various synclines east of the SAF to explore the software's ability to unfold (reverse model) units. For the initial round of modeling, strike-slip movement has been omitted as the fault algorithm was designed primarily for extensional or compressional environments. Preliminary forward modeling of originally undeformed strata along the blind thrust produced geometries similar to those in the present-day 3D geologic model. The modeled amount of folding produced in hanging wall strata was less severe, suggesting these units were slightly folded before displacement. Based on these results, the algorithm shows potential in predicting deformation related to blind thrusts. Contraction in the region varies with fold axis location and orientation. MoveTm's unfolding algorithm can allow researchers to measure the amount of contraction a fold represents, and compare that amount across the modeled area as a way of observing regional stress patterns. The unfolding algorithm also allows for passive deformation of strata unconformably underlying the fold; one example reveals a steeper orientation of Cretaceous units prior to late Miocene deformation. Such modeling capabilities can allow for a better understanding of the structural history of the region.

  19. Marine neotectonic investigation of the San Gregorio Fault Zone on the northern flank of Monterey Canyon, offshore central California

    NASA Astrophysics Data System (ADS)

    Maier, K. L.; Paull, C. K.; Brothers, D. S.; McGann, M.; Caress, D. W.; Lundsten, E. M.; Anderson, K.; Gwiazda, R.

    2014-12-01

    The San Gregorio Fault Zone (SGFZ) is part of the North American-Pacific plate boundary and is thought to accommodate right-lateral offset up to 10 mm/yr. Because much of the SGFZ in Monterey Bay, central California, lies offshore in steep submarine canyon bathymetry, little is known of its recent activity. We provide initial direct evidence for faulting where the SGFZ has been interpreted based on canyon morphology to cross the northern flank of Monterey Canyon. High-resolution multibeam bathymetry and chirp subbottom profiles were acquired during 13 dives with the Monterey Bay Aquarium Research Institute's (MBARI) Autonomous Underwater Vehicle (AUV) from 2009-2014 on the northern flank of Monterey Canyon, extending from the shelf edge ~15 km offshore Santa Cruz to ~1850 m water depth. Chirp profiles resolve layered sediments up to ~40 m subsurface in this region, and no fault scarps or seafloor lineaments are visible in the 1-m resolution multibeam bathymetry. At least one subsurface fault is identified within the SGFZ by offset reflections across a discrete, nearly vertical fault. However, this fault is only imaged where mass wasting has exhumed older strata to within ~25 m of the seafloor. Numerous slumps scars on the seafloor and packages of chaotic internal reflectivity in chirp profiles suggest that submarine landslide processes dominate the study area. To constrain the age of reflections offset by the fault, MBARI's Remotely Operated Vehicle (ROV) Doc Ricketts, sampled faces of slump scars where the offset reflections crop out using vibracores and horizontal push cores. Radiocarbon dating of foraminifera within these core samples is being used to constrain the last recorded movement on the fault. Application of AUV and ROV methods allows detailed neotectonic investigation of significant offshore structures, like the SGFZ, that contribute to hazard assessment.

  20. Three-dimensional magnetotelluric inversion in practice—the electrical conductivity structure of the San Andreas Fault in Central California

    NASA Astrophysics Data System (ADS)

    Tietze, Kristina; Ritter, Oliver

    2013-10-01

    3-D inversion techniques have become a widely used tool in magnetotelluric (MT) data interpretation. However, with real data sets, many of the controlling factors for the outcome of 3-D inversion are little explored, such as alignment of the coordinate system, handling and influence of data errors and model regularization. Here we present 3-D inversion results of 169 MT sites from the central San Andreas Fault in California. Previous extensive 2-D inversion and 3-D forward modelling of the data set revealed significant along-strike variation of the electrical conductivity structure. 3-D inversion can recover these features but only if the inversion parameters are tuned in accordance with the particularities of the data set. Based on synthetic 3-D data we explore the model space and test the impacts of a wide range of inversion settings. The tests showed that the recovery of a pronounced regional 2-D structure in inversion of the complete impedance tensor depends on the coordinate system. As interdependencies between data components are not considered in standard 3-D MT inversion codes, 2-D subsurface structures can vanish if data are not aligned with the regional strike direction. A priori models and data weighting, that is, how strongly individual components of the impedance tensor and/or vertical magnetic field transfer functions dominate the solution, are crucial controls for the outcome of 3-D inversion. If deviations from a prior model are heavily penalized, regularization is prone to result in erroneous and misleading 3-D inversion models, particularly in the presence of strong conductivity contrasts. A `good' overall rms misfit is often meaningless or misleading as a huge range of 3-D inversion results exist, all with similarly `acceptable' misfits but producing significantly differing images of the conductivity structures. Reliable and meaningful 3-D inversion models can only be recovered if data misfit is assessed systematically in the frequency

  1. Correlation of coal beds in the Fruitland Formation as interpreted from geophysical logs, east-central San Juan County, New Mexico

    USGS Publications Warehouse

    Sandberg, Dorothy T.

    1986-01-01

    Correlation of coal beds in the Fruitland Formation (Upper Cretaceous) in the subsurface, from interpretation of geophysical logs, is an outgrowth of unpublished studies of deep coal on the Navajo Reservation by the author in the Toadlena 30 x 60 minute quadrangle, New Mexico, and by W. J. Mapel in the Farmington 30 x 60 minute quadrangle, New Mexico.  The lines of sections of this report extend eastward from the reservation into east-central San Juan County, which is in the western part of the San Juan Basin.  In this area, the rocks dip gently northeast toward the central part of the basin.  The thick coal is less than 1,500 feet beneath the surface.  Of the 53 logs in the sections, 48 are from oil- and gas-test holes, and 5 are from coal-test holes (see table 1).  Stratigraphic relations of the Upper Cretaceous Lewis Shale, Pictured Cliffs Sandstone, and Fruitland Formation, shown on the cross sections and briefly reviewed below, have been previously described for this or other parts of the San Juan Basin by Hayes and Zapp (1955), Beaumont (1971), Fassett and hinds (1971), O;Sullivan and other (1972), and Molenaar (1983), among others.

  2. Status and Understanding of Groundwater Quality in the Central-Eastside San Joaquin Basin, 2006: California GAMA Priority Basin Project

    USGS Publications Warehouse

    Landon, Matthew K.; Belitz, Kenneth; Jurgens, Bryant C.; Justin T. Kulongoski, Justin T.; Johnson, Tyler D.

    2010-01-01

    Groundwater quality in the approximately 1,695-square-mile Central Eastside San Joaquin Basin (Central Eastside) study unit was investigated as part of the Priority Basin Project (PBP) of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA PBP was developed in response to the California Groundwater Quality Monitoring Act of 2001, and is being conducted by the California State Water Resources Control Board in collaboration with the U.S. Geological Survey and the Lawrence Livermore National Laboratory. The GAMA Central Eastside study unit was designed to provide a spatially unbiased assessment of untreated-groundwater quality, as well as a statistically consistent basis for comparing water quality throughout California. During March through June 2006, samples were collected from 78 wells in Stanislaus and Merced Counties, 58 of which were selected using a spatially distributed, randomized grid-based method to provide statistical representation of the study unit (grid wells), and 20 of which were sampled to evaluate changes in water chemistry along groundwater-flow paths (understanding wells). Water-quality data from the California Department of Public Health (CDPH) database also were used for the assessment. An assessment of the current status of the groundwater quality included collecting samples from wells for analysis of anthropogenic constituents such as volatile organic compounds (VOCs) and pesticides, as well as naturally occurring constituents such as major ions and trace elements. The assessment of status is intended to characterize the quality of untreated-groundwater resources within the primary aquifer system, not the treated drinking water delivered to consumers by water purveyors. The primary aquifer system (hereinafter, primary aquifer) is defined as that part of the aquifer corresponding to the perforation interval of wells listed in the CDPH database for the Central Eastside study unit. The quality of groundwater in shallower or

  3. Sea level fluctuations in central California at subtidal to decadal and longer time scales with implications for San Francisco Bay, California

    USGS Publications Warehouse

    Ryan, H.F.; Noble, M.A.

    2007-01-01

    Sea level elevations from near the mouth of San Francisco Bay are used to describe the low-frequency variability of forcing of the coastal ocean on the Bay at a variety of temporal scales. About 90% of subtidal fluctuations in sea level in San Francisco Bay are driven by the sea level variations in the coastal ocean that propagate into the Bay at the estuary mouth. We use the 100-year sea level record available at San Francisco to document a 1.9 mm/yr mean sea level rise, and to determine fluctuations related to El Nino-Southern Oscillation (ENSO) and other climatic events. At time scales greater than 1 year, ENSO dominates the sea level signal and can result in fluctuations in sea level of 10-15 cm. Alongshore wind stress data from central California are also analyzed to determine the impact of changes in coastal elevation at the mouth of San Francisco Bay within the synoptic wind band of 2-30 days. At least 40% of the subtidal fluctuations in sea level of the Bay are tied to the large-scale regional wind field affecting sea level variations in the coastal ocean, with little local, direct wind forcing of the Bay itself. The majority of the subtidal sea level fluctuations within the Bay that are not related to the coastal ocean sea level signal are forced by an east-west sea level gradient resulting from tidally induced variations in sea level at specific beat frequencies that are enhanced in the northern reach of the Bay. River discharge into the Bay through the Sacramento and San Joaquin River Delta also contributes to the east-west gradient, but to a lesser degree. ?? 2007 Elsevier Ltd. All rights reserved.

  4. Central San Francisco Bay suspended-sediment transport processes study and comparison of continuous and discrete measurements of suspended-solids concentrations

    USGS Publications Warehouse

    Schoellhamer, David H.

    1994-01-01

    Sediments are an important component of the San Francisco Bay estuarine system. Potentially toxic substances, such as metals and pesticides, adsorb to sediment particles. The sediments on the bottom of the Bay provide the habitat for benthic communities which can ingest these substances and introduce them into the food web. The bottom sediments are also a reservoir of nutrients. The transport and fate of suspended sediment is an important factor in determining the transport and fate of the constituents adsorbed on the sediment. Suspended sediments also limit light availability in the bay, which limits photosynthesis and primary production, and deposit in ports and shipping channels, which require dredging. Dredged materials are disposed in Central San Francisco Bay.

  5. Late Holocene movement along the San Andreas Fault at Melendy Ranch: Implications for the distribution of fault slip in central California

    NASA Astrophysics Data System (ADS)

    Perkins, James A.; Sims, John D.; Sturgess, Steven S.

    1989-08-01

    An alluvial deposit of the San Benito River at Melendy Ranch, which is located along the creeping segment of the San Andreas fault in central California, records an 800-year-long average slip rate of 22-4+6 mm/yr. The rate is calculated from one radiocarbon age and two measures of displacement and is based on various sedimentologic and stratigraphic data. Numerous other radiocarbon ages were determined for detrital charcoal from the alluvium at Melendy Ranch. These radiocarbon ages appear to be at variance with the age of the alluvium on the basis of sedimentologic and stratigraphic data. The 22 mm/yr long-term rate is similar to the 20-23 mm/yr range of slip rates that are recorded by geodetic instruments at Melendy Ranch and a 22 mm/yr slip rate recorded by an offset corral fence built in 1945. This suggests that the historic rate of movement along the San Andreas fault at Melendy Ranch is near its 800-year average. The long-term slip rate of about 22 mm/yr at Melendy Ranch is 12-5+7 mm/yr less than the long-term rate found along the San Andreas fault south of the creeping segment, and it is greater than the minimum long-term rate of about 12 mm/yr found along the fault north of the creeping segment on the San Francisco Peninsula. Thus the long-term slip-rate data suggest a ˜20 mm/yr northwestward decrease in slip rate along the San Andreas fault. The northwestward decrease in long-term slip rate is attributed to a two-part transfer of slip, south of Hollister, from the San Andreas fault to the Paicines and Calaveras faults. If the Paicines and Calaveras faults south of Hollister have a combined long-term slip rate of about ˜20 mm/yr, then a similar rate may also represent slip across the Calaveras and Hayward faults north of Hollister.

  6. San Marino.

    PubMed

    1985-02-01

    San Marino, an independent republic located in north central Italy, in 1983 had a population of 22,206 growing at an annual rate of .9%. The literacy rate is 97% and the infant mortality rate is 9.6/1000. The terrain is mountainous and the climate is moderate. According to local tradition, San Marino was founded by a Christian stonecutter in the 4th century A.D. as a refuge against religious persecution. Its recorded history began in the 9th century, and it has survived assaults on its independence by the papacy, the Malatesta lords of Rimini, Cesare Borgia, Napoleon, and Mussolini. An 1862 treaty with the newly formed Kingdom of Italy has been periodically renewed and amended. The present government is an alliance between the socialists and communists. San Marino has had its own statutes and governmental institutions since the 11th century. Legislative authority at present is vested in a 60-member unicameral parliament. Executive authority is exercised by the 11-member Congress of State, the members of which head the various administrative departments of the goverment. The posts are divided among the parties which form the coalition government. Judicial authority is partly exercised by Italian magistrates in civil and criminal cases. San Marino's policies are tied to Italy's and political organizations and labor unions active in Italy are also active in San Marino. Since World War II, there has been intense rivalry between 2 political coalitions, the Popular Alliance composed of the Christian Democratic Party and the Independent Social Democratic Party, and the Liberty Committee, coalition of the Communist Party and the Socialist Party. San Marino's gross domestic product was $137 million and its per capita income was $6290 in 1980. The principal economic activities are farming and livestock raising, along with some light manufacturing. Foreign transactions are dominated by tourism. The government derives most of its revenue from the sale of postage stamps to

  7. Application of high resolution DEM data to detect rock damage from geomorphic signals along the central San Jacinto Fault

    NASA Astrophysics Data System (ADS)

    Wechsler, Neta; Rockwell, Thomas K.; Ben-Zion, Yehuda

    2009-12-01

    We analyze geomorphic properties extracted from LiDAR and SRTM (Shuttle Radar Topography Mission) data to test whether the damage zone along the central San Jacinto Fault (SJF) zone can be resolved with remotely-sensed data in a quantitative fashion. The SJF is one of the most active faults in southern California, with well expressed geomorphology and a fast slip rate, as seen in the geology and by GPS. We use ArcMap and the TauDEM toolbox to compare several morphometric parameters, including drainage density (Dd), on both sides of the fault, using a 1 km and a 5 km buffer for the LiDAR and SRTM data, respectively. We also analyze the spatial patterns of Dd near the fault, using two different definitions of spatial Dd. The high resolution of the LiDAR data allows us to focus on a single fault, eliminating the effects of parallel nearby faults. From the LiDAR data we find that the highest Dd values occur in areas between two fault strands, followed generally by rocks on the northeast side of the fault, with the lowest Dd values occurring on the southwest side of the fault. The SRTM data shows a band of high Dd values centered on the main fault trace with ~ 1 km width. Our results indicate that there is a strong correlation between drainage density and proximity to the fault, with zones of structural complexity along the fault displaying the highest Dd. We interpret this to largely be an effect of degree of rock damage, as these are areas that are expected to be more damaged, and field observations support this contention. If we are correct, then it appears that the northeast side of the SJF is generally more damaged. South of the trifurcation area there is evidence that the signal is reversed on the larger scale, with more damage on the southwest side of the fault inferred from the SRTM data, possibly caused by extension between the Coyote Creek and Clark faults. The implications of the observed asymmetry could be geological evidence for rupture propagation

  8. Counterclockwise rotations in the Late Eocene-Oligocene volcanic fields of San Luis Potosí and Sierra de Guanajuato (eastern Mesa Central, Mexico)

    NASA Astrophysics Data System (ADS)

    Andreani, Louis; Gattacceca, Jerôme; Rangin, Claude; Martínez-Reyes, Juventino; Demory, François

    2014-12-01

    We used paleomagnetic and structural data to investigate the late Eocene-Oligocene tectonic evolution of the Mesa Central area in Mexico. The Mesa Central was affected by NW-trending faults (Tepehuanes-San Luis fault system) coeval with a Late Eocene-Oligocene ignimbrite flare-up and by post-27 Ma NNE-trending grabens related to the Basin and Range. We obtained reliable paleomagnetic directions from 61 sites within the Late Eocene-Oligocene volcanic series (~ 30 to ~ 27 Ma) of the San Luis Potosí volcanic field and Sierra de Guanajuato. For each site we also measured the anisotropy of magnetic susceptibility (AMS). Tilt corrections were made using AMS data for 33 sites where in situ bedding measurements were not available. Paleomagnetic directions indicate counterclockwise rotations of about 10° with respect to stable North America after 30-25 Ma. Structural data suggest that the volcanic succession was mainly affected by normal faults. However, we also found evidences for oblique or horizontal striae showing a left-lateral component along NW-trending faults and a right lateral component along NE-trending faults. Both motions are consistent with a N-S extension oblique to the Tepehuanes-San Luis fault system. Previous paleomagnetic studies in northern and southern Mexico show the prevalence of minor left-lateral shear components along regional-scale transpressional and transtensional lineaments. Our paleomagnetic data may reflect thus small vertical-axis rotations related to a minor shear component coeval with the Oligocene intra-arc extension in central Mexico.

  9. Evidence of late Gelasian dispersal of African fauna at Coste San Giacomo (Anagni Basin, central Italy): Early Pleistocene environments and the background of early human occupation in Europe

    NASA Astrophysics Data System (ADS)

    Bellucci, L.; Bona, F.; Corrado, P.; Magri, D.; Mazzini, I.; Parenti, F.; Scardia, G.; Sardella, R.

    2014-07-01

    Since the late 70s, the Early Pleistocene (Gelasian) site of Coste San Giacomo (Anagni Basin, central Italy) has been known amongst palaeontologists for its diverse vertebrate fauna. During the last 5 years, new excavations and the drilling of a 46-m-deep core have provided novel pieces of information. Palaeomagnetic data, pollen and small vertebrates analyses are presented here for the first time and combined with the updated list of the large vertebrates and ostracod analysis in a multidisciplinary perspective. Large and small mammals, pollen and ostracod analyses have allowed an integrated palaeoenvironmental reconstruction of the sedimentary sequence, depicting the evolution of the alluvial plain in the surrounding landscape. Moreover, magnetostratigraphy, pollen and small mammal biochronological data have confirmed the position of the Coste San Giacomo Faunal Unit, focusing the possible age of the mammal assemblage around 2.1 Ma, in a reversed phase before the base of the Olduvai chron. In particular, the occurrence of the large vole Mimomys pliocaenicus has important biochronological significance. The Coste San Giacomo site offers a unique opportunity to investigate the faunal and environmental changes that occurred in Mediterranean Europe during the Early Pleistocene, coinciding with major climatic changes at a global scale. The occurrence of taxa such as Hippopotamus sp. in the assemblage provides evidence of early dispersal events of African taxa prior to the early Homo diffusion into Europe.

  10. Numerical simulation of ground-water flow in the central part of the western San Joaquin Valley, California

    USGS Publications Warehouse

    Belitz, Kenneth; Phillips, Steven P.; Gronberg, Jo Ann M.

    1993-01-01

    The occurrence of selenium in agricultural drain water in the central part of the western San Joaquin Valley, California, has focused concern on strategies for managing shallow, saline ground water. To assess alternatives to agricultural drains, a three-dimensional, finite-difference numerical model of the regional groundwater flow system was developed. This report documents the mathematical approach used to model the flow system, the data base on which the model is based, and the methods used to calibrate the model. The 550-square-mile study area includes parts of the Panoche Creek alluvial fan and parts of the Little Panoche Creek and Cantua Creek alluvial fans. The model simulates transient flow in the semiconfined and confined zones above and below the Corcoran Clay Member of the Tulare Formation of Pleistocene age. The model incorporates areally distributed ground-water recharge, areally and vertically distributed pumping, regional-collector drains in the Wesdands Water District (operative from 1980 to 1985), on-farm drains in parts of the Panoche, Broadview, and Firebaugh Water Districts, and bare-soil evaporation (which occurs if the water table is within 7 feet of land surface). The model also incorporates texture-based estimates of hydraulic conductivity, where texture is defined as the fraction of coarse-grained deposits present in a given subsurface interval. The numerical model was developed using hydrologic data from 1972 to 1988. Most of the parameters incorporated into the model were evaluated independently of the model, including system geometry, the distribution of texture, the altitudes of the water table and potentiometric surface of the confined zone in 1972 (initial condition), the hydraulic conductivity of coarse-grained deposits derived from the Coast Ranges, the hydraulic conductivity of coarse-grained deposits derived from the Sierra Nevada, specific storage, recharge, pumping, and parameters needed to incorporate drains and bare

  11. Continuation of the San Andreas fault system into the upper mantle: Evidence from spinel peridotite xenoliths in the Coyote Lake basalt, central California

    NASA Astrophysics Data System (ADS)

    Titus, Sarah J.; Medaris, L. Gordon; Wang, Herbert F.; Tikoff, Basil

    2007-01-01

    The Coyote Lake basalt, located near the intersection of the Hayward and Calaveras faults in central California, contains spinel peridotite xenoliths from the mantle beneath the San Andreas fault system. Six upper mantle xenoliths were studied in detail by a combination of petrologic techniques. Temperature estimates, obtained from three two-pyroxene geothermometers and the Al-in-orthopyroxene geothermometer, indicate that the xenoliths equilibrated at 970-1100 °C. A thermal model was used to estimate the corresponding depth of equilibration for these xenoliths, resulting in depths between 38 and 43 km. The lattice preferred orientation of olivine measured in five of the xenolith samples show strong point distributions of olivine crystallographic axes suggesting that fabrics formed under high-temperature conditions. Calculated seismic anisotropy values indicate an average shear wave anisotropy of 6%, higher than the anisotropy calculated from xenoliths from other tectonic environments. Using this value, the anisotropic layer responsible for fault-parallel shear wave splitting in central California is less than 100 km thick. The strong fabric preserved in the xenoliths suggests that a mantle shear zone exists below the Calaveras fault to a depth of at least 40 km, and combining xenolith petrofabrics with shear wave splitting studies helps distinguish between different models for deformation at depth beneath the San Andrea fault system.

  12. 9. Partial elevation of west side showing pillar, central and ...

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

    9. Partial elevation of west side showing pillar, central and southern sections, from San Antonio Highway Bridge. - Puente Ferroviario San Antonio, Spanning San Antonio Channel at PR-1, San Juan, San Juan Municipio, PR

  13. Preliminary Results from SAFOD Phase 3: Implications for the state of stress and shear localization in and near the San Andreas Fault at depth in central California

    NASA Astrophysics Data System (ADS)

    Zoback, M. D.; Hickman, S. H.; Ellsworth, W.; Kirschner, D.; Pennell, N. B.; Chery, J.; Sobolev, S.

    2007-12-01

    Strain localization along the San Andreas fault system in central California appears to result from both a thermally-weak lower crust and upper mantle (reflecting northward migration of the Mendocino triple junction and its associated slab window) and a fault zone in the upper brittle crust that is distinctly weaker than the surrounding crust. Geophysical logs and cuttings analyses from SAFOD Phase 2 (completed in 2005) revealed the San Andreas Fault Zone at approximately 2.7 km depth to be relatively broad (about 250 m), with several discrete, localized zones only 2-3 m wide with very low P- and S-wave velocities and low resistivity. Since 2005, fault creep at two of these localized zones has deformed the casing and thus demonstrates that these zones are actively creeping faults. During SAFOD Phase 3, continuous cores were obtained across these two actively creeping faults. Another core was obtained near the geologic boundary between the Salinian terrane (Pacific plate) and Great Valley/Franciscan terrane (North American plate). Each set of cores reveal zones of profound strain localization and probable weakening. These include ultracataclasites, highly-foliated shear zones (some containing veined serpentine) and intervals that appear to be cohesionless, compacted fault gouges which are likely composed of minerals with low frictional strength. No evidence of significantly elevated fluid pressure is observed within the fault zone. Information about the state of stress in the fault zone and adjacent crust comes from observations and modeling of wellbore failures, direct measurements of the magnitude of the least principal stress and the direction of stress-induced shear wave velocity anisotropy. Observations made after rotary drilling through the fault in 2005 indicate that the San Andreas is a weak fault imbedded in a strong crust. These observations made within about 100 m of the active fault zone at 2.7 km include i) stress orientations that are nearly

  14. Seismicity rate changes along the central California coast due to stress changes from the 2003 M 6.5 San Simeon and 2004 M 6.0 Parkfield earthquakes

    USGS Publications Warehouse

    Aron, A.; Hardebeck, J.L.

    2009-01-01

    We investigated the relationship between seismicity rate changes and modeled Coulomb static stress changes from the 2003 M 6.5 San Simeon and the 2004 M 6.0 Parkfield earthquakes in central California. Coulomb stress modeling indicates that the San Simeon mainshock loaded parts of the Rinconada, Hosgri, and San Andreas strike-slip faults, along with the reverse faults of the southern Los Osos domain. All of these loaded faults, except for the San Andreas, experienced a seismicity rate increase at the time of the San Simeon mainshock. The Parkfield earthquake occurred 9 months later on the loaded portion of the San Andreas fault. The Parkfield earthquake unloaded the Hosgri fault and the reverse faults of the southern Los Osos domain, which both experienced seismicity rate decreases at the time of the Parkfield event, although the decreases may be related to the decay of San Simeon-triggered seismicity. Coulomb stress unloading from the Parkfield earthquake appears to have altered the aftershock decay rate of the southern cluster of San Simeon after-shocks, which is deficient compared to the expected number of aftershocks from the Omori decay parameters based on the pre-Parkfield aftershocks. Dynamic stress changes cannot explain the deficiency of aftershocks, providing evidence that static stress changes affect earthquake occurrence. However, a burst of seismicity following the Parkfield earthquake at Ragged Point, where the static stress was decreased, provides evidence for dynamic stress triggering. It therefore appears that both Coulomb static stress changes and dynamic stress changes affect the seismicity rate.

  15. Character and evolution of the ground-water flow system in the central part of the western San Joaquin Valley, California

    SciTech Connect

    Belitz, K.

    1988-01-01

    The occurrence of selenium in agricultural drain water derived from the western San Joaquin Valley, California, has focused concern on the groundwater flow system of the western valley. Previous work and recently collected texture and water level data were used to evaluate the character and evolution of the regional groundwater flow system in the central part of the western valley, with particular emphasis on the deposits overlying the Corcoran Clay Member of the Tulane Formation. The development of irrigated agriculture in the central part of the western valley has significantly altered the flow system. Percolation of irrigation water past crop roots has caused a rise in the altitude of the water table in mid-fan and distal-fan areas. Pumpage of groundwater from wells has caused a lowering of the water table beneath parts of the fanheads and a lowering of the potentiometric surface of the confined zone over much of the western valley. The combination of percolation and pumpage has resulted in development of a large downward hydraulic head gradient in the semi-confined zone and has created a groundwater divide along the western margin of the valley. Surface water deliveries from the California Aqueduct have allowed a decrease in pumpage and a consequent recovery in hydraulic head throughout the system. 30 refs., 24 figs.

  16. The Point Sal–Point Piedras Blancas correlation and the problem of slip on the San Gregorio–Hosgri fault, central California Coast Ranges

    USGS Publications Warehouse

    Colgan, Joseph P.; Stanley, Richard G.

    2016-01-01

    Existing models for large-magnitude, right-lateral slip on the San Gregorio–Hosgri fault system imply much more deformation of the onshore block in the Santa Maria basin than is supported by geologic data. This problem is resolved by a model in which dextral slip on this fault system increases gradually from 0–10 km near Point Arguello to ∼150 km at Cape San Martin, but such a model requires abandoning the cross-fault tie between Point Sal and Point Piedras Blancas, which requires 90–100 km of right-lateral slip on the southern Hosgri fault. We collected stratigraphic and detrital zircon data from Miocene clastic rocks overlying Jurassic basement at both localities to determine if either section contained unique characteristics that could establish how far apart they were in the early Miocene. Our data indicate that these basins formed in the early Miocene during a period of widespread transtensional basin formation in the central Coast Ranges, and they filled with sediment derived from nearby pre-Cenozoic basement rocks. Although detrital zircon data do not indicate a unique source component in either section, they establish the maximum depositional age of the previously undated Point Piedras Blancas section to be 18 Ma. We also show that detrital zircon trace-element data can be used to discriminate between zircons of oceanic crust and arc affinity of the same age, a potentially useful tool in future studies of the California Coast Ranges. Overall, we find no characteristics in the stratigraphy and provenance of the Point Sal and Point Piedras Blancas sections that are sufficiently unique to prove whether they were far apart or close together in the early Miocene, making them of questionable utility as piercing points.

  17. Heat flow, strong near-fault seismic waves, and near-fault tectonics on the central San Andreas Fault

    NASA Astrophysics Data System (ADS)

    Sleep, Norman H.

    2016-05-01

    The main San Andreas Fault strikes subparallel to compressional folds and thrust faults. Its fault-normal traction is on average a factor of γ=1+2μthr>(√(1+μthr2)+μthr>), where μthr is the coefficient of friction for thrust faults, times the effective lithostatic pressure. A useful upper limit for μthr of 0.6 (where γ is 3.12) is obtained from the lack of heat flow anomalies by considering off-fault convergence at a rate of 1 mm/yr for 10 km across strike. If the fault-normal traction is in fact this high, the well-known heat flow constraint of average stresses of 10-20 MPa during strike slip on the main fault becomes more severe. Only a few percent of the total slip during earthquakes can occur at the peak stress before dynamic mechanisms weaken the fault. The spatial dimension of the high-stress rupture-tip zone is ˜10 m for γ = 3.12 and, for comparison, ˜100 m for γ = 1. High dynamic stresses during shaking occur within these distances of the fault plane. In terms of scalars, fine-scale tectonic stresses cannot exceed the difference between failure stress and dynamic stress. Plate-scale slip causes stresses to build up near geometrical irregularities of the fault plane. Strong dynamic stresses near the rupture tip facilitate anelastic deformation with the net effects of relaxing the local deviatoric tectonic stress and accommodating deformation around the irregularities. There also is a mild tendency for near-fault material to extrude upward. Slip on minor thrust faults causes the normal traction on the main fault to be spatially variable.

  18. Late 20th Century benthic foraminiferal distribution in Central San Francisco Bay, California: Influence of the Trochammina hadai invasion

    USGS Publications Warehouse

    McGann, Mary L.

    2014-01-01

    Samples collected from 1965 onward were also compared with those from 1998 to investigate how the distribution of benthic foraminifera in Central Bay has changed over the latter half of the 20th Century, particularly in response to the invasion by Trochammina hadai. In 1998, T. hadai was recovered at 46 of 55 sites in Central Bay, comprising from 0.3 to 97% (mean = 23%) of the foraminiferal fauna. With the species’ affiliation for shallow environments, it is not unexpected that it dominated the fauna of the Shallow Subtidal Biofacies (68-97%, mean = 77%) and was also a significant component of the Intermediate Subtidal Biofacies (7-51%, averaging 28%). In the deeper waters west of Alcatraz Island, the abundance of T. hadai was significantly less (mean = 8%), most likely reflecting allochthonous specimens that were the result of post-mortem transport. A cluster analysis clearly distinguishes pre- and post-invasion biofacies, illustrating how dominant T. hadai has become in Central Bay.

  19. Borehole geophysical, fluid, and hydraulic properties within and near the freshwater/saline-water transition zone, San Antonio segment of the Edwards aquifer, south-central Texas, 2010-11

    USGS Publications Warehouse

    Thomas, Jonathan V.; Stanton, Gregory P.

    2013-01-01

    The freshwater zone of the San Antonio segment of the Edwards aquifer is used by residents of San Antonio and numerous other rapidly growing communities in south-central Texas as their primary water supply source. This freshwater zone is bounded to the south and southeast by a saline-water zone with an intermediate zone transitioning from freshwater to saline water (transition zone). As demands on this water supply increase, there is concern that the transition zone could potentially move, resulting in more saline water in current freshwater supply wells. Since 1985, the U.S. Geological Survey, San Antonio Water System, and other Federal and State agencies have conducted studies to better understand the transition zone.

  20. Simulation of Streamflow, Evapotranspiration, and Groundwater Recharge in the Lower San Antonio River Watershed, South-Central Texas, 2000-2007

    USGS Publications Warehouse

    Lizarraga, Joy S.; Ockerman, Darwin J.

    2010-01-01

    The U.S. Geological Survey (USGS), in cooperation with the San Antonio River Authority, the Evergreen Underground Water Conservation District, and the Goliad County Groundwater Conservation District, configured, calibrated, and tested a watershed model for a study area consisting of about 2,150 square miles of the lower San Antonio River watershed in Bexar, Guadalupe, Wilson, Karnes, DeWitt, Goliad, Victoria, and Refugio Counties in south-central Texas. The model simulates streamflow, evapotranspiration (ET), and groundwater recharge using rainfall, potential ET, and upstream discharge data obtained from National Weather Service meteorological stations and USGS streamflow-gaging stations. Additional time-series inputs to the model include wastewater treatment-plant discharges, withdrawals for cropland irrigation, and estimated inflows from springs. Model simulations of streamflow, ET, and groundwater recharge were done for 2000-2007. Because of the complexity of the study area, the lower San Antonio River watershed was divided into four subwatersheds; separate HSPF models were developed for each subwatershed. Simulation of the overall study area involved running simulations of the three upstream models, then running the downstream model. The surficial geology was simplified as nine contiguous water-budget zones to meet model computational limitations and also to define zones for which ET, recharge, and other water-budget information would be output by the model. The model was calibrated and tested using streamflow data from 10 streamflow-gaging stations; additionally, simulated ET was compared with measured ET from a meteorological station west of the study area. The model calibration is considered very good; streamflow volumes were calibrated to within 10 percent of measured streamflow volumes. During 2000-2007, the estimated annual mean rainfall for the water-budget zones ranged from 33.7 to 38.5 inches per year; the estimated annual mean rainfall for the entire

  1. Simulation of streamflow, evapotranspiration, and groundwater recharge in the lower San Antonio River Watershed, South-Central Texas, 2000-2007

    USGS Publications Warehouse

    Lizarraga, Joy S.; Ockerman, Darwin J.

    2010-01-01

    The U.S. Geological Survey (USGS), in cooperation with the San Antonio River Authority, the Evergreen Underground Water Conservation District, and the Goliad County Groundwater Conservation District, configured, calibrated, and tested a watershed model for a study area consisting of about 2,150 square miles of the lower San Antonio River watershed in Bexar, Guadalupe, Wilson, Karnes, DeWitt, Goliad, Victoria, and Refugio Counties in south-central Texas. The model simulates streamflow, evapotranspiration (ET), and groundwater recharge using rainfall, potential ET, and upstream discharge data obtained from National Weather Service meteorological stations and USGS streamflow-gaging stations. Additional time-series inputs to the model include wastewater treatment-plant discharges, withdrawals for cropland irrigation, and estimated inflows from springs. Model simulations of streamflow, ET, and groundwater recharge were done for 2000-2007. Because of the complexity of the study area, the lower San Antonio River watershed was divided into four subwatersheds; separate HSPF models were developed for each subwatershed. Simulation of the overall study area involved running simulations of the three upstream models, then running the downstream model. The surficial geology was simplified as nine contiguous water-budget zones to meet model computational limitations and also to define zones for which ET, recharge, and other water-budget information would be output by the model. The model was calibrated and tested using streamflow data from 10 streamflow-gaging stations; additionally, simulated ET was compared with measured ET from a meteorological station west of the study area. The model calibration is considered very good; streamflow volumes were calibrated to within 10 percent of measured streamflow volumes. During 2000-2007, the estimated annual mean rainfall for the water-budget zones ranged from 33.7 to 38.5 inches per year; the estimated annual mean rainfall for the entire

  2. Social vulnerability as a contributing factor to disasters in Central America: A case study at San Vicente volcano, El Salvador

    NASA Astrophysics Data System (ADS)

    Bowman, L. J.; Henquinet, K. B.; Gierke, J. S.; Rose, W. I.

    2012-12-01

    El Salvador's geographic location on the Pacific Ring of Fire at the juncture of the Caribbean and Cocos plates exposes its population to various natural hazards, including volcanic eruptions (e.g., Santa Ana in 2005), earthquakes (e.g., January 13 and February 13, 2001), and landslides and flooding due to tropical rainfall events (e.g., Hurricane Mitch in 1998, Hurricane Stan in 2005). Such hazards can be devastating anywhere, but the condition of social vulnerability in which many Salvadorans currently live exacerbates the impacts of these hazards. Aspects contributing to most rural Salvadorans being marginalized include a colonial history marked by ethnic discrimination and laws prohibiting land ownership, lack of access to desirable land in an agrarian society, a poor education system, global economic policies that foster inequality, political marginalization, a bloody civil conflict, and rampant criminality and violence. In November 2009, an extreme rainfall event triggered landslides and lahars killing over 200 people at San Vicente volcano. This disaster brought to light weaknesses in disaster preparedness and response plans. Despite the existence of recent hazard maps and lahar inundation models (2001), and the occurrence of a similar, deadly event in 1934, the population appeared to be unaware of the risk, and lacked the organization and decision-making protocols to adequately deal with the emergency. Therefore, in the aftermath of the 2009 lahars, much of the focus on disaster risk reduction (DRR) initiatives has been aimed at the communities affected by this most recent event. Our study examines root causes of social vulnerability and assesses the apparent impacts of these interventions on the population, including individual's perceptions regarding these risk-reducing interventions. Two years after the event, though aid abounds, many people remain vulnerable to hazards in this area. Semi-structured interviews were completed with survivors of the 2009

  3. Two-dimensional seismic image of the San Andreas Fault in the Northern Gabilan Range, central California: Evidence for fluids in the fault zone

    USGS Publications Warehouse

    Thurber, C.; Roecker, S.; Ellsworth, W.; Chen, Y.; Lutter, W.; Sessions, R.

    1997-01-01

    A joint inversion for two-dimensional P-wave velocity (Vp), P-to-S velocity ratio (Vp/Vs), and earthquake locations along the San Andreas fault (SAF) in central California reveals a complex relationship among seismicity, fault zone structure, and the surface fault trace. A zone of low Vp and high Vp/Vs lies beneath the SAF surface trace (SAFST), extending to a depth of about 6 km. Most of the seismic activity along the SAF occurs at depths of 3 to 7 km in a southwest-dipping zone that roughly intersects the SAFST, and lies near the southwest edge of the low Vp and high Vp/Vs zones. Tests indicate that models in which this seismic zone is significantly closer to vertical can be confidently rejected. A second high Vp/Vs zone extends to the northeast, apparently dipping beneath the Diablo Range. Another zone of seismicity underlies the northeast portion of this Vp/Vs high. The high Vp/Vs zones cut across areas of very different Vp values, indicating that the high Vp/Vs values are due to the presence of fluids, not just lithology. The close association between the zones of high Vp/Vs and seismicity suggests a direct involvement of fluids in the faulting process. Copyright 1997 by the American Geophysical Union.

  4. Trace metals in sediments and Zostera marina of San Ignacio and Ojo de Liebre lagoons in the central pacific coast of Baja California, Mexico.

    PubMed

    Macías-Zamora, J V; Sánchez-Osorio, J L; Ríos-Mendoza, L M; Ramírez-Alvarez, N; Huerta-Díaz, M A; López-Sánchez, D

    2008-08-01

    San Ignacio and Ojo de Liebre lagoons in central Baja California, Mexico are nursery and grazing grounds for whales and turtles. Ojo de Liebre Lagoon also supports a salt mine operation. By concentrating trace metals via evaporation, this activity might harm biota. Consequently, salt mining might be incompatible with the lagoon's ecological role. Eelgrass can incorporate these elements and reroute them to other organisms. Trace metals in sediments (Cd, Co, Cu, Mn, Ni, Pb, Zn, and Fe) were measured at both lagoons. Some (Cu, Mn, Pb, and Zn) were also measured in Zostera marina patches at both lagoons. The results did not show elevated metal concentration at any lagoon, either for sediments or eelgrass. No statistically significant differences between lagoons were found. However, eelgrass at both lagoons showed larger concentration ranges than in sediments. Also, a correlation exists between sediment metal concentration and its concentration in eelgrass. Surprisingly, several sediment metal concentrations are higher than those considered as elevated for the Southern California Bight.

  5. Medical therapeutic itineraries of women with breast cancer diagnosis affiliated to the People's Health Insurance in San Luis Potosí, central Mexico.

    PubMed

    Tejada-Tayabas, Luz María; Salcedo, Liseth Amell; Espino, Joel Monárrez

    2015-01-01

    This study aims to describe the medical itineraries followed by breast cancer women affiliated to the People's Health Insurance in San Luis Potosí, central Mexico. We used an ethnographic approach based on oral histories of 12 women diagnosed with breast cancer in the year prior to the first meeting. Two face-to-face sessions per participant lasting 60 minutes each were conducted followed by a telephone interview. Content and diachronic analyses were used. Three main itineraries were identified: (1) diagnostic process, (2) final diagnosis to treatment, and (3) cancer control and relapse. Findings suggested that infrastructure and human resources to adequately screen and timely diagnose breast cancer were scant and insufficiently trained, respectively. Deferral of medical assessment was related with lack of information about breast cancer consequences, with women being afraid of a positive result, and with economic constraints. The current screening program needs to be redesigned to prevent diagnostic delays, as these seem to explain the high frequency of advanced stages reported at the time of diagnosis.

  6. High-resolution seismic-reflection and marine-magnetic data from offshore central California--San Gregorio to Point Sur

    USGS Publications Warehouse

    Sliter, Ray W.; Johnson, Samuel Y.; Watt, Janet T.; Scheirer, Daniel S.; Allwardt, Parker; Triezenberg, Peter J.

    2013-01-01

    The U.S. Geological Survey collected high-resolution seismic-reflection data on four surveys (S-N1-09-MB, S-15-10-NC, S-06-11-MB, and S-04-12-MB) and marine-magnetic data on one survey (S-06-11-MB) between 2009 and 2012, offshore of central California between San Gregorio and Point Sur. This work was supported in part by the California Seafloor Mapping Program. The survey areas span about 120 km of California's coast (including Monterey Bay). Most data were collected aboard the U.S. Geological Survey R/V Parke Snavely. Cumulatively, approximately 1,410 km of single-channel seismic-reflection data were acquired, mainly using a SIG 2mille minisparker. About 44 km of data were collected simultaneously using an EdgeTech Chirp 512. Subbottom acoustic penetration spanned tens to several hundreds of meters, variable by location. Marine magnetic data were collected on approximately 460 km of track lines (mainly in southern Monterey Bay) using a Geometrics G882 cesium-vapor marine magnetometer. This report includes maps and navigation files of the surveyed transects, linked to Google Earth™ software, as well as digital data files showing images of each transect in SEG-Y and JPEG formats. The images of bedrock, sediment deposits, and tectonic structure provide geologic information that is essential to hazard assessment, regional sediment management, and coastal and marine spatial planning at Federal, State and local levels, as well as to future research on the geomorphic, sedimentary, tectonic, and climatic record of central California.

  7. Character and evolution of the ground-water flow system in the central part of the western San Joaquin Valley, California

    USGS Publications Warehouse

    Belitz, K.R.

    1988-01-01

    The occurrence of selenium in agricultural drain water derived from the western San Joaquin Valley, California, has focused concern on the groundwater flow system of the western valley. Previous work and recently collected texture and water level data were used to evaluate the character and evolution of the regional groundwater flow system in the central part of the western valley, with particular emphasis on the deposits overlying the Corcoran Clay Member of the Tulane Formation. The Corcoran Clay Member, where present, divides the flow system into an upper semiconfined zone and a lower confined zone. Above the Corcoran, three geohydrologic units can be recognized: Coast Range alluvium, Sierran sand, and flood-basin deposits. These units differ in texture, hydrologic properties, and oxidation state. The development of irrigated agriculture in the central part of the western valley has significantly altered the flow system. Percolation of irrigation water past crop roots has caused a rise in the altitude of the water table in mid-fan and distal-fan areas. Pumpage of groundwater from wells has caused a lowering of the water table beneath parts of the fanheads and a lowering of the potentiometric surface of the confined zone over much of the western valley. The combination of percolation and pumpage has resulted in development of a large downward hydraulic head gradient in the semi-confined zone and has created a groundwater divide along the western margin of the valley. Surface water deliveries from the California Aqueduct have allowed a decrease in pumpage and a consequent recovery in hydraulic head throughout the system. (Author 's abstract)

  8. Time-dependent model of aseismic slip on the central San Andreas Fault from InSAR time series and repeating earthquakes

    NASA Astrophysics Data System (ADS)

    Khoshmanesh, M.; Shirzaei, M.; Nadeau, R. M.

    2015-09-01

    The Central segment of San Andreas Fault (CSAF) is characterized by a nearly continuous right-lateral aseismic slip. However, observations of the creep rate obtained using small characteristically repeating earthquakes (CREs) show pulses of creep along the CSAF, which may indicate spatially and temporally variable seismic hazard along the CSAF. Therefore, the goal of this study is to obtain a high-resolution time-dependent model of creep along the CSAF to examine this hypothesis. To this end, we apply a time-dependent creep modeling approach, which combines interferometric synthetic aperture radar (InSAR) surface deformation time series and observations of fault creep obtained from CREs. The SAR data set includes C band scenes acquired by the ERS-2 and Envisat satellites between 2003 and 2011. The resulting creep rate distribution implies a peak rate up to 32 mm/yr along the central part of the CSAF. Afterslip due to the 2004 Parkfield earthquake on the southeastern segment of the CSAF is also manifest in the model, and there is clear evidence of creep pulsing along strike and depth of the CSAF. Estimated annual rate of slip deficit accumulation is equivalent to a magnitude 5.6-5.7 earthquake. Taking advantage of the time-dependence of our model, we also refine the scaling relationship, which associates the released seismic moment due to a CRE event with the amount of creep on the fault, surrounding the CRE patches. This study provides the first kinematic model of creep pulsing, constrained using geodetic and seismic data, which can enhance time-dependent seismic hazard maps and improve earthquake operational forecast models.

  9. Structure and geomorphology of the "big bend" in the Hosgri-San Gregorio fault system, offshore of Big Sur, central California

    NASA Astrophysics Data System (ADS)

    Johnson, S. Y.; Watt, J. T.; Hartwell, S. R.; Kluesner, J. W.; Dartnell, P.

    2015-12-01

    The right-lateral Hosgri-San Gregorio fault system extends mainly offshore for about 400 km along the central California coast and is a major structure in the distributed transform margin of western North America. We recently mapped a poorly known 64-km-long section of the Hosgri fault offshore Big Sur between Ragged Point and Pfieffer Point using high-resolution bathymetry, tightly spaced single-channel seismic-reflection and coincident marine magnetic profiles, and reprocessed industry multichannel seismic-reflection data. Regionally, this part of the Hosgri-San Gregorio fault system has a markedly more westerly trend (by 10° to 15°) than parts farther north and south, and thus represents a transpressional "big bend." Through this "big bend," the fault zone is never more than 6 km from the shoreline and is a primary control on the dramatic coastal geomorphology that includes high coastal cliffs, a narrow (2- to 8-km-wide) continental shelf, a sharp shelfbreak, and a steep (as much as 17°) continental slope incised by submarine canyons and gullies. Depth-converted industry seismic data suggest that the Hosgri fault dips steeply to the northeast and forms the eastern boundary of the asymmetric (deeper to the east) Sur Basin. Structural relief on Franciscan basement across the Hosgri fault is about 2.8 km. Locally, we recognize five discrete "sections" of the Hosgri fault based on fault trend, shallow structure (e.g., disruption of young sediments), seafloor geomorphology, and coincidence with high-amplitude magnetic anomalies sourced by ultramafic rocks in the Franciscan Complex. From south to north, section lengths and trends are as follows: (1) 17 km, 312°; (2) 10 km, 322°; (3)13 km, 317°; (4) 3 km, 329°; (5) 21 km, 318°. Through these sections, the Hosgri surface trace includes several right steps that vary from a few hundred meters to about 1 km wide, none wide enough to provide a barrier to continuous earthquake rupture.

  10. Regression models of monthly water-level change in and near the Closed Basin Division of the San Luis Valley, south-central Colorado

    USGS Publications Warehouse

    Watts, Kenneth R.

    1995-01-01

    The Bureau of Reclamation is developing a water-resource project, the Closed Basin Division, in the San Luis Valley of south-central Colorado that is designed to salvage unconfined ground water that currently is discharged as evapotranspiration. The water table in and near the 130,000-acre Closed Basin Division area will be lowered by an annual withdrawal of as much as 100,000 acre-feet of ground water from the unconfined aquifer. The legislation authorizing the project limits resulting drawdown of the water table in preexisting irrigation and domestic wells outside the Closed Basin Division to a maximum of 2 feet. Water levels in the closed basin in the northern part of the San Luis Valley historically have fluctuated more than 2 feet in response to water-use practices and variation of climatically controlled recharge and discharge. Declines of water levels in nearby wells that are caused by withdrawals in the Closed Basin Division can be quantified if water-level fluctuations that result from other water-use practices and climatic variations can be estimated. This study was done to evaluate water-level change at selected observation wells in and near the Closed Basin Division. Regression models of monthly water-level change were developed to predict monthly water-level change in 46 selected observation wells. Predictions of monthly water-level change are based on one or more of the following: elapsed time, cosine and sine functions with an annual period, streamflow depletion of the Rio Grande, electrical use for agricultural purposes, runoff into the closed basin, precipitation, and mean air temperature. Regression models for five of the wells include only an intercept term and either an elapsed-time term or terms determined by the cosine and sine functions. Regression models for the other 41 wells include 1 to 4 of the 5 other variables, which can vary from month to month and from year to year. Serial correlation of the residuals was detected in 24 of the

  11. Geophysical Exploration of Fractured-Media Aquifers at the Mexican Mesa Central: Satellite City, San Luis Potosí, Mexico

    NASA Astrophysics Data System (ADS)

    López Loera, Héctor; Ramos Leal, José Alfredo; Dávila Harris, Pablo; Torres Gaytan, David Ernesto; Martinez Ruiz, Victor Julian; Gogichaishvili, Avto

    2014-09-01

    Groundwater is scarce in arid and semi-arid zones in the Mexican Mesa Central. It is found at depths over 200 m, and its movement is primarily through fractures. This work aims to present a geophysical methodology, which shows the potential of combining natural and induced methods to locate confined aquifers in fault zones. The studies begin by interpreting the aeromagnetic survey, mainly by seeking lineaments associated with low magnetic anomalies, which are correlated with fault zones, and/or fractures and/or geological contacts where ferromagnetic minerals have undergone oxidation due to their association with recharge zones. These aeromagnetic lineaments are confirmed on land by a ground magnetic survey. After locating these areas, interpreted as permeability zones, their possible association with moist zones is confirmed by applying the vertical electrical sounding (VES) technique. H-type curve is associated with the presence of saturated zones. This study used the proposed methodology to interpret four main aeromagnetic lineaments and 12 main ground magnetic lineaments in a 36 km2 (6 km × 6 km) area. Twenty-six SEV were performed over these magnetic lineaments, of which about 50 % were associated with H-type resistivity curves, interpreted as being associated with moisture. Of the 12 VES with inferred groundwater potential, two wells have been drilled to date, one having an extraction flow of 70 lps.

  12. Geophysical Exploration of Fractured-Media Aquifers at the Mexican Mesa Central: Satellite City, San Luis Potosí, Mexico

    NASA Astrophysics Data System (ADS)

    López Loera, Héctor; Ramos Leal, José Alfredo; Dávila Harris, Pablo; Torres Gaytan, David Ernesto; Martinez Ruiz, Victor Julian; Gogichaishvili, Avto

    2015-01-01

    Groundwater is scarce in arid and semi-arid zones in the Mexican Mesa Central. It is found at depths over 200 m, and its movement is primarily through fractures. This work aims to present a geophysical methodology, which shows the potential of combining natural and induced methods to locate confined aquifers in fault zones. The studies begin by interpreting the aeromagnetic survey, mainly by seeking lineaments associated with low magnetic anomalies, which are correlated with fault zones, and/or fractures and/or geological contacts where ferromagnetic minerals have undergone oxidation due to their association with recharge zones. These aeromagnetic lineaments are confirmed on land by a ground magnetic survey. After locating these areas, interpreted as permeability zones, their possible association with moist zones is confirmed by applying the vertical electrical sounding (VES) technique. H-type curve is associated with the presence of saturated zones. This study used the proposed methodology to interpret four main aeromagnetic lineaments and 12 main ground magnetic lineaments in a 36 km2 (6 km × 6 km) area. Twenty-six SEV were performed over these magnetic lineaments, of which about 50 % were associated with H-type resistivity curves, interpreted as being associated with moisture. Of the 12 VES with inferred groundwater potential, two wells have been drilled to date, one having an extraction flow of 70 lps.

  13. 19. REGIONAL MAP, SALINAS RIVER PROJECT, CAMP SAN LUIS OBISPO, ...

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

    19. REGIONAL MAP, SALINAS RIVER PROJECT, CAMP SAN LUIS OBISPO, IN CENTRAL PORTION OF SAN LUIS OBISPO, CALIFORNIA. Leeds Hill Barnard & Jewett - Consulting Engineers, February 1942. - Salinas River Project, Cuesta Tunnel, Southeast of U.S. 101, San Luis Obispo, San Luis Obispo County, CA

  14. Ground-Water Quality Data in the Central Eastside San Joaquin Basin 2006: Results from the California GAMA Program

    USGS Publications Warehouse

    Landon, Matthew K.; Belitz, Kenneth

    2008-01-01

    Ground-water quality in the approximately 1,695-square-mile Central Eastside study unit (CESJO) was investigated from March through June 2006 as part of the Statewide Basin Assessment Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Statewide Basin Assessment project was developed in response to the Groundwater Quality Monitoring Act of 2001 and is being conducted by the California State Water Resources Control Board (SWRCB) in collaboration with the U.S. Geological Survey (USGS) and the Lawrence Livermore National Laboratory (LLNL). The study was designed to provide a spatially unbiased assessment of raw ground-water quality within CESJO, as well as a statistically consistent basis for comparing water quality throughout California. Samples were collected from 78 wells in Merced and Stanislaus Counties. Fifty-eight of the 78 wells were selected using a randomized grid-based method to provide statistical representation of the study unit (grid wells). Twenty of the wells were selected to evaluate changes in water chemistry along selected lateral or vertical ground-water flow paths in the aquifer (flow-path wells). The ground-water samples were analyzed for a large number of synthetic organic constituents [volatile organic compounds (VOCs), gasoline oxygenates and their degradates, pesticides and pesticide degradates], constituents of special interest [perchlorate, N-nitrosodimethylamine (NDMA), and 1,2,3-trichloropropane (1,2,3-TCP)], inorganic constituents that can occur naturally [nutrients, major and minor ions, and trace elements], radioactive constituents, and microbial indicators. Naturally occurring isotopes [tritium, carbon-14, and uranium isotopes and stable isotopes of hydrogen, oxygen, nitrogen, sulfur, and carbon], and dissolved noble and other gases also were measured to help identify the source and age of the sampled ground water. Quality-control samples (blanks, replicates, samples for matrix spikes) were collected

  15. Effects of reservoir installation, San Juan-Chama Project water, and reservoir operations on streamflow and water quality in the Rio Chama and Rio Grande, northern and central New Mexico, 1938-2000

    USGS Publications Warehouse

    Langman, Jeff B.; Anderholm, Scott K.

    2004-01-01

    The coordinated operation of Heron, El Vado, and Abiquiu Dams on the Rio Chama and Cochiti Dam on the Rio Grande and the importation of Colorado River Basin water by the San Juan-Chama Project have altered streamflow and water quality of the Rio Chama and Rio Grande in northern and central New Mexico. The coordinated retention of streamflow in the four reservoirs increased median streamflows, decreased extreme flows, and decreased periods of small streamflow; inflow of San Juan-Chama Project water increased overall streamflow in the Rio Chama and Rio Grande. These changes to streamflow decreased specific conductance and suspended-sediment concentration and increased pH in the Rio Chama and the Rio Grande. Following construction of Heron and Cochiti Dams and integration of reservoir operations on the Rio Chama and the Rio Grande, the inflow of San Juan-Chama Project water and retention of snowmelt runoff influenced water quality. These influences varied by season because reservoir releases fluctuated according to downstream user needs and annual streamflow variation. The influences of San Juan-Chama Project water and retained snowmelt on water quality diminished with downstream flow as the Rio Grande was subjected to various natural and anthropogenic inflows. Because of the variability and type of seasonal influences, streamflow did not have a strong annual correlation with water quality in the Rio Chama or the Rio Grande.

  16. Time-dependent Model of Aseismic slip on the Central San Andreas Fault from InSAR Time Series and Repeating Earthquakes

    NASA Astrophysics Data System (ADS)

    Khoshmanesh, M.; Shirzaei, M.; Nadeau, R. M.

    2014-12-01

    The Central segment of the San Andreas Fault (CSAF) is characterized by a nearly continuous right-lateral aseismic slip. Geodetic observations of surface deformation along CSAF indicate interseismic strain accumulation with a rate of about 10 mm/yr. The creep rates obtained using Characteristic Repeating Earthquakes (CRE) show pulses of creep affecting most of the CSAF, suggesting spatiotemporal variability of seismic hazard. Therefore, a high resolution time-dependent model of creep on the CSAF can greatly enhance the knowledge of aseismic and seismic faulting processes as well as the seismic hazard estimates. We used InSAR surface deformation time series in conjunction with observations of fault creep obtained from CRE. The SAR data set includes C-band scenes acquired by the ERS-2 and Envisat during period 2003-2011, comprising 46 images, resulted in about 150 interferograms. Within the same observation period, the CRE data set includes more than 630 repeating sequences. Understanding the spatiotemporal distribution of creep, we implement a time-dependent modeling scheme, allowing us to jointly invert the surface deformation time series and CRE estimates of the fault creep.The distribution of obtained creep rate on the CSAF includes features similar to that reported in earlier works. The map of long-term slip rate reveals that fastest creep rate occurs at the central part of CSAF with an average rate of 27 mm/yr, which is less than the long-term shearing rate. Moving northwestward, the slip rate gradually drops to less than half of its long-term rate. The spatiotemporal map of the creep includes unique features such as afterslip due to the 2004 Parkfield earthquake affecting the southeastern part of the CSAF and the clear evidence of creep pulsing along strike and depth of the CSAF with a period of 1.5 to 2 years. Considering 34.5 mm/yr as the long-term shearing rate, the zone of afterslip is characterized by relaxation time of about 16.35 years. The moment

  17. Ecological and water quality impairment resulting from the New Idria Mercury Mine and natural sources in the San Carlos and Silver Creek watersheds, central California

    NASA Astrophysics Data System (ADS)

    Rytuba, J. J.; Hothem, R.; Goldstein, D.; Brussee, B.

    2011-12-01

    The New Idria Mercury Mine in central California is the second largest mercury (Hg) deposit in North America and has been proposed as a US EPA Superfund Site based on ecological impairment to the San Carlos and Silver Creek watersheds. Water, sediment, and biota were sampled in San Carlos Creek in the mine area and downstream for 25 km into the watershed termed Silver Creek. Release of acid rock drainage (ARD) and erosion of mine tailings have impacted the watershed during 120 years of mining and since the mine was closed in 1972. The watershed can be divided into three segments based on water and sediment composition, Hg sources and concentrations, and biodiversity of aquatic invertebrates. Creek waters in segment no. 1 above the mine area consist of Mg-Ca-CO3 meteoric water with pH 8.73. Hg concentrations are elevated in both sediment (100μg/g), and in waters (60 ng/L) because of erosion of Hg mine tailings in the upper part of the watershed. Invertebrate biodiversity is the highest of the sites sampled in the watershed, with seven families (six orders) of aquatic invertebrates collected and six other families observed. In the mine area isotopically heavy ARD (pH 2.7) with high levels of Fe(II), SO4, and total Hg (HgT: 76.7 ng/L) enters and mixes with meteoric creek water, constituting from 10-15% of the water in the 10-km long second creek segment downstream from the mine. Oxidation of Fe(II) from ARD results in precipitation of FeOOH which is transported and deposited as an Fe precipitate that has high Hg and MMeHg concentration (Hg: 15.7-79 μg/g, MMeHg: 0.31 - 1.06 ng/g). Concentrations of HgT are uniformly high (1530-2890 ng/L) with particulate Hg predominant. MMeHg ranges from 0.21-0.99 ng/L. In the area just downstream from the ARD source, biodiversity of invertebrates was low, with only one taxa (water striders) available in sufficient numbers and mass (> 1 g)_to be sampled. Biodiversity further downstream was also low, with only up to 2 families present

  18. Simulation of streamflow and estimation of recharge to the Edwards aquifer in the Hondo Creek, Verde Creek, and San Geronimo Creek watersheds, south-central Texas, 1951-2003

    USGS Publications Warehouse

    Ockerman, Darwin J.

    2005-01-01

    The U.S. Geological Survey, in cooperation with the San Antonio Water System, constructed three watershed models using the Hydrological Simulation Program—FORTRAN (HSPF) to simulate streamflow and estimate recharge to the Edwards aquifer in the Hondo Creek, Verde Creek, and San Geronimo Creek watersheds in south-central Texas. The three models were calibrated and tested with available data collected during 1992–2003. Simulations of streamflow and recharge were done for 1951–2003. The approach to construct the models was to first calibrate the Hondo Creek model (with an hourly time step) using 1992–99 data and test the model using 2000–2003 data. The Hondo Creek model parameters then were applied to the Verde Creek and San Geronimo Creek watersheds to construct the Verde Creek and San Geronimo Creek models. The simulated streamflows for Hondo Creek are considered acceptable. Annual, monthly, and daily simulated streamflows adequately match measured values, but simulated hourly streamflows do not. The accuracy of streamflow simulations for Verde Creek is uncertain. For San Geronimo Creek, the match of measured and simulated annual and monthly streamflows is acceptable (or nearly so); but for daily and hourly streamflows, the calibration is relatively poor. Simulated average annual total streamflow for 1951–2003 to Hondo Creek, Verde Creek, and San Geronimo Creek is 45,400; 32,400; and 11,100 acre-feet, respectively. Simulated average annual streamflow at the respective watershed outlets is 13,000; 16,200; and 6,920 acre-feet. The difference between total streamflow and streamflow at the watershed outlet is streamflow lost to channel infiltration. Estimated average annual Edwards aquifer recharge for Hondo Creek, Verde Creek, and San Geronimo Creek watersheds for 1951–2003 is 37,900 acrefeet (5.04 inches), 26,000 acre-feet (3.36 inches), and 5,940 acre-feet (1.97 inches), respectively. Most of the recharge (about 77 percent for the three watersheds

  19. San Antonio, Texas, USA

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This sharp, cloud free view of San Antonio, Texas (29.5N, 98.5W) illustrates the classic pattern of western cities. The city has a late nineteenth century Anglo grid pattern overlaid onto an earlier, less regular Hispanic settlement. A well marked central business district having streets laid out north/south and east/west is surrounded by blocks of suburban homes and small businesses set between the older colonial radial transportation routes.

  20. Improving the Flash Flood Frequency Analysis using dendrogeomorphological evidences in the Arenal River crossing Arenas de San Pedro Village (Spanish Central System)

    NASA Astrophysics Data System (ADS)

    Ruiz-Villanueva, V.; Ballesteros, J. A.; Díez-Herrero, A.; Bodoque, J. M.

    2009-04-01

    The flash flood frequency analysis in mountainous catchments presents specific scientific challenges. One of the challenges is the relevant gradient in precipitation intensity with altitude. Another challenge is the lack of information from rainfall or discharge gauge stations or from documentary sources. Dendrogeomorphology studies the response in the wood growth pattern and the botanical signs on the trees affected by geomorphological processes. With regard to the flood frequency, the dendrogeomorphological evidences bring forward valuable infomation about single past events (with annual or even seasonal precision) and their occurrence periodicity. The main macro-evidence that we can find in the tree trunk is a stem scar originated by a wound in the bark of the tree. When the tree grows, this wound remains reflected in the tree ring sequence. The best way to analyze the tree ring sequence is by using a complete section of the trunk, this couldn't be possible unless the tree is cut down. Due to the unfeasibility of cutting down the trees, in Dendrogeomorphology is enough to obtain an increment core, using a Pressler borer. Nevertheless, this study has been based on complete stem sections analysis facilitated for the felling works in the riverine vegetation in the Arenal River, carried out by the Tagus River Water Authority. These felling works have allowed us to obtain sections and to analyze the stump of the tree in situ. On this way, 100 samples of Alnus glutinosa and Fraxinus angustifolia located by the river along the Arenal River crossing Arenas de San Pedro Village (Ávila, northern slopes of the Gredos Mountain Range in the Spanish Central System) have been analyzed. This village is known for its historical problems of flood during extreme events. A meticulous fieldwork has been carried out. Every sample was analyzed locating its geomorphological position, the distance to the riverbed and the height of the stump in which the evidences were observed. Using a

  1. Insights into Surface Manifestation of Aseismic vs. Coseismic Strike-Slip Faulting from UAV Imagery of Creep-Induced Surface Fracturing Along the Central San Andreas Fault

    NASA Astrophysics Data System (ADS)

    Bunds, M. P.; Toke, N. A.; Lawrence, A.; Arrowsmith, R.; Salisbury, J. B.

    2015-12-01

    Left-stepping en echelon fractures formed at the Dry Lake Valley paleoseismic site (DLV, 36.470N, 121.057W) on the central creeping segment of the San Andreas Fault (SAF) during the 2012-14 drought. The fractures were investigated using high resolution DEMs and orthophotos made by applying Structure from Motion processing to photos taken using a UAV and handheld cameras on 9/20/2014. At DLV the SAF is marked by a distinctive 2-7 m high west-facing scarp that extends northwestward from a dilational step-over. The orthophotos and DEMs were used to measure 110 fractures along a 37 m section of scarp and 15 additional fracture sets along a further 79 m of scarp. The fractures averaged 54 cm long by 1.8 cm wide with 22% overlap, and were mode 1 opening fractures that on average trended 184o, nearly perpendicular to the maximum extension direction for right-lateral slip along the 144o - trending SAF. The fractures occurred in ~5 m long sets that were themselves left-stepping, on average trended 159o, and were confined to a 3-4 m wide zone along the fault scarp. We interpret the fracture sets to be incipient Riedel shears with a component of extension across them based on the orientation of the sets relative to the SAF, the obliquity of the individual fractures to the trend of the sets, and the presence of topographic lows along them. We conservatively estimate 2.5 ± 1 cm of right-lateral creep on the SAF was recorded in the opening of the fractures, which probably began forming at most 21 months before the photographic survey based on precipitation records and prior site inspection. From these results and the 2.5-3.2 cm/yr creep rate for the SAF, we infer that at least ~30%, and probably 50-80% or more of creep occurs along the narrow 5-50 m wide primary geomorphic expression of the fault, and that the same amount of creep can be accommodated by brittle fracturing in a narrow 3-4 m wide zone along the fault scarp during drought periods. In comparison to seismically

  2. Insights into Surface Manifestation of Aseismic vs. Coseismic Strike-Slip Faulting from UAV Imagery of Creep-Induced Surface Fracturing Along the Central San Andreas Fault

    NASA Astrophysics Data System (ADS)

    Bunds, M. P.; Toke, N. A.; Lawrence, A.; Arrowsmith, R.; Salisbury, J. B.

    2014-12-01

    Left-stepping en echelon fractures formed at the Dry Lake Valley paleoseismic site (DLV, 36.470N, 121.057W) on the central creeping segment of the San Andreas Fault (SAF) during the 2012-14 drought. The fractures were investigated using high resolution DEMs and orthophotos made by applying Structure from Motion processing to photos taken using a UAV and handheld cameras on 9/20/2014. At DLV the SAF is marked by a distinctive 2-7 m high west-facing scarp that extends northwestward from a dilational step-over. The orthophotos and DEMs were used to measure 110 fractures along a 37 m section of scarp and 15 additional fracture sets along a further 79 m of scarp. The fractures averaged 54 cm long by 1.8 cm wide with 22% overlap, and were mode 1 opening fractures that on average trended 184o, nearly perpendicular to the maximum extension direction for right-lateral slip along the 144o - trending SAF. The fractures occurred in ~5 m long sets that were themselves left-stepping, on average trended 159o, and were confined to a 3-4 m wide zone along the fault scarp. We interpret the fracture sets to be incipient Riedel shears with a component of extension across them based on the orientation of the sets relative to the SAF, the obliquity of the individual fractures to the trend of the sets, and the presence of topographic lows along them. We conservatively estimate 2.5 ± 1 cm of right-lateral creep on the SAF was recorded in the opening of the fractures, which probably began forming at most 21 months before the photographic survey based on precipitation records and prior site inspection. From these results and the 2.5-3.2 cm/yr creep rate for the SAF, we infer that at least ~30%, and probably 50-80% or more of creep occurs along the narrow 5-50 m wide primary geomorphic expression of the fault, and that the same amount of creep can be accommodated by brittle fracturing in a narrow 3-4 m wide zone along the fault scarp during drought periods. In comparison to seismically

  3. Thermal history of the upper mantle beneath a young back-arc extensional zone: ultramafic xenoliths from San Luis Potosí, Central Mexico

    NASA Astrophysics Data System (ADS)

    Heinrich, Wilhelm; Besch, Thomas

    1992-06-01

    At the San Luis Potosí (SLP) volcanic field (Central Mexico), Quaternary basanites and tuff breccias have sampled a suite of ultramafic xenoliths, predominately spinel lherzolites, spinel-olivine websterites, spinel pyroxenites, and hornblende-rich pyroxenites. Spinel lherzolites from the La Ventura maars have protogranular to equigranular textures, those from the Santo Domingo maars are strongly sheared. Both spinel-lherzolite types show similar whole-rock major and trace-element abundances. They are fertile to slightly depleted with mineralogical and geochemical heterogeneities induced by partial melting processes. Pyroxenites with either magmatic or metamorphic textures are high-pressure cumulates. Hornblende-rich pyroxenites are genetically linked to the host basanites. Most of the protogranular spinel lherzolites contain veinlets of glass along grain boundaries. These glasses are chemically homogeneous and have trachybasaltic to trachyandesitic compositions. Mg- and Fe2+-partitioning between olivine and glass suggests chemical equilibrium between the melts represented by the glasses and the spinel-lherzolite mineral assemblage at about 1,000°C and 10 to 15 kbar. The melts are interpreted to be of upper mantle origin. They may have been formed by in-situ partial melting in the presence of volatiles or represent percolating melts chemically buffered by the spinel-lherzolite mineral assemblage at uppermost mantle conditions. Mineral chemistry in all rock types of the whole xenolith suite reveals distinct disequilibrium features reflecting partial re-equilibration stages towards lower temperatures estimated to be from 1,050°C to 850°C at 9 to 15 kbar. The presence of similar zoning and exsolution features mainly documented in pyroxenes along with similar maximum and minimum temperatures requires all sampled xenoliths to have undergone the same temperature regime within the upper mantle. The sheared spinel lherzolites from the Sto. Domingo field are interpreted

  4. Eocene to Quaternary mafic-intermediate volcanism in San Luis Potosí, central Mexico: The transition from Farallon plate subduction to intra-plate continental magmatism

    NASA Astrophysics Data System (ADS)

    Aguillón-Robles, Alfredo; Tristán-González, Margarito; de Jesús Aguirre-Díaz, Gerardo; López-Doncel, Rubén A.; Bellon, Hervé; Martínez-Esparza, Gilberto

    2014-04-01

    The San Luis Potosí Volcanic Field (SLPVF) of central Mexico includes volcanic sequences of felsic, intermediate and basic compositions that were erupted as discrete episodes from the Eocene to the Pleistocene. Volcanism was dominated by widespread and voluminous rhyolitic ignimbrites of the mid-Tertiary Ignimbrite Flare-up. However, the complete volcanic history must consider basaltic and andesitic Eocene-Pleistocene volcanic successions that provide key evidence for understanding the geochemical evolution of the volcanism in the SLPVF during this time span. Five sequences are recognized according to their geochemical characteristics, each comprising a volcano-tectonic episode. The first episode comprises basaltic andesites and andesites erupted during three intervals, 45-42 Ma, 36-31 Ma, and 31-30 Ma. The oldest was derived from subduction magmatism, whereas the youngest has an intra-plate magmatic signature and this represents the transition from the end of a long lasting subduction regime of the Farallon plate to the initiation of intra-plate continental extension in the North American plate. The second episode, at 29.5-28 Ma, comprises a bimodal succession of high-silica rhyolites and alkaline basalts (hawaiites) that are interpreted as magmatism generated in an intra-plate continental extension regime during the Basin and Range faulting. The third episode, at 21 Ma, is characterized by trachybasalts and trachyandesites that represent mantle basaltic melts that were contaminated through assimilation of the lower crust during advanced stage of intra-plate extension that started at Oligocene. The fourth episode includes 12 Ma alkaline basalts and andesites that were erupted from fissures. These mantle derived magmas evolved to andesites by crustal anatexis and crystal fractionation within a continued, extensional, intra-plate regime. Lastly, the fifth episode comprises 5.0 to 0.6 Ma alkaline basalts (basanites) containing mantle xenoliths, that were erupted

  5. Magnetic properties of the remagnetized Middle-Ordovician limestones of the Ponón Trehué Formation (San Rafael Block, central-western Argentina): Insights into the Permian widespread Sanrafaelic overprint

    NASA Astrophysics Data System (ADS)

    Fazzito, Sabrina Y.; Rapalini, Augusto E.

    2016-10-01

    The widespread Sanrafaelic remagnetization reset most of the early Cambrian to mid-Ordovician carbonate platform of the Argentine Precordillera and the calcareous units of the San Rafael Block. We conducted a detailed rock-magnetic study on the Middle-Ordovician limestones of the Ponón Trehué Formation at both limbs of a tight anticline exposed in the San Rafael Block (Mendoza province, central-western Argentina) that are carriers of a syntectonic magnetization of Permian age. We found that the magnetic overprint in the Ponón Trehué Formation is carried by both pyrrhotite and magnetite, with goethite and subordinate haematite likely related to weathering. Hysteresis parameters, frequency dependence of magnetic susceptibility, Cisowski and modified Lowrie-Fuller tests suggest the presence of ultrafine particles of chemical origin. Demagnetization of natural remanent magnetization and of three-axis isothermal remanence confirm pyrrhotite and magnetite as important contributors to the remanence. Both minerals carry the same magnetic syntectonic component suggesting a coeval or nearly coeval remanence acquisition and therefore mineral formation. This and the results of the magnetic fabric analyses indicate an authigenic origin of the magnetic minerals during folding associated with the Sanrafaelic tectonic phase (ca. 280 Ma). Although the chemically active (oxidizing?) fluids expelled from the orogen as it developed in the early Permian is a viable explanation for the Sanrafaelic remagnetization, the role of the nearly coeval magmatism in Precordillera and the San Rafael Block remains to be properly evaluated.

  6. Digital data and derivative products from a high-resolution aeromagnetic survey of the central San Luis basin, covering parts of Alamosa, Conejos, Costilla, and Rio Grande counties, Colorado, and Taos county, New Mexico

    USGS Publications Warehouse

    Bankey, Viki; Grauch, V.J.S.; Webbers, Ank; PRJ, Inc

    2005-01-01

    This report describes data collected from a high-resolution aeromagnetic survey flown over the central San Luis basin during October, 2004, by PRJ, Inc., on contract to the U.S. Geological Survey (USGS). The survey extends from just north of Alamosa, Colorado, southward to just northwest of Taos, New Mexico. It covers large parts of the San Luis Valley in Alamosa, Conejos, Costilla, and Rio Grande Counties, southern Colorado, and the Taos Plateau in Taos County, northern New Mexico. The survey was designed to complement two surveys previously acquired along the eastern borders of the San Luis Basin over the vicinities of Taos, New Mexico (Bankey and others, 2004a) and Blanca, Colorado (Bankey and others, 2004b). Our overall objective in conducting these surveys is to improve knowledge of the subsurface geologic framework in order to understand ground-water systems in populated alluvial basins along the Rio Grande. These USGS efforts are conducted in collaboration with other federal, state, and local governmental entities where possible.

  7. Water-level, borehole geophysical log, and water-quality data from wells transecting the freshwater/saline-water interface of the San Antonio segment of the Edwards Aquifer, South-Central Texas, 1999-2007

    USGS Publications Warehouse

    Lambert, Rebecca B.; Hunt, Andrew G.; Stanton, Gregory P.; Nyman, Michael B.

    2009-01-01

    As a part of a 9-year (1999-2007) study done by the U.S. Geological Survey in cooperation with the San Antonio Water System to improve understanding of the San Antonio segment of the Edwards aquifer, south-central Texas, in and near the freshwater/saline-water transition zone of the aquifer, the U.S. Geological Survey collected water-level, borehole geophysical, and water-quality data during 1999-2007 from 37 wells arranged in nine transects (except for two wells) across the freshwater/saline-water interface of the aquifer. This report presents the data collected and also describes the data-collection, analytical, and quality-assurance methods used. The wells, constructed with casing from land surface into the upper part of the aquifer and completed as open hole in the aquifer, are in Uvalde County (East Uvalde transect), in Medina County (South Medina and Devine wells), in Bexar County (Pitluk, Mission, and San Antonio transects), in Comal and Guadalupe Counties (Tri-County transect), in Comal County (New Braunfels transect), and in Hays County (Fish Hatchery, San Marcos, and Kyle transects). Data collected included continuous water level at 18 wells; fluid electrical conductivity and temperature with depth (fluid profiles) obtained by borehole geophysical logging of 15 wells; discrete (periodic) samples for major ions and trace elements at 36 wells; stable isotopes or stable isotopes and tritium at 27 wells; dissolved gases obtained by pumping (or collecting flow) of 19 wells; and continuous specific conductance and temperature at three of the wells equipped with continuous water-level sensors.

  8. Three thousand years of flank and central vent eruptions of the San Salvador volcanic complex (El Salvador) and their effects on El Cambio archeological site: a review based on tephrostratigraphy

    NASA Astrophysics Data System (ADS)

    Ferrés, D.; Delgado Granados, H.; Hernández, W.; Pullinger, C.; Chávez, H.; Castillo Taracena, C. R.; Cañas-Dinarte, C.

    2011-09-01

    The volcanic events of the last 3,000 years at San Salvador volcanic complex are reviewed using detailed stratigraphic records exposed in new excavations between 2005 and 2007, at El Cambio archeological site (Zapotitán Valley, El Salvador), and in other outcrops on the northern and northwestern sectors of the complex. The sequences that overlie Tierra Blanca Joven (cal. 429 ± 107 ad), from the Ilopango caldera, comprise the Loma Caldera (cal. 590 ± 90 ad) and El Playón (1658-1671) deposits and the San Andrés Tuff (cal. 1031 ± 29 ad), related to El Boquerón Volcano. The surge deposits within the El Playón, San Andrés Tuff and overlying Talpetate II sequences indicate the significance of phreatomagmatic phases in both central vent and flank eruptions during the last 1,600 years. Newly identified volcanic deposits underlying Tierra Blanca Joven at El Cambio extend the stratigraphic record of the area to 3,000 years bp. Paleosols interstratified with those deposits contain cultural artifacts which could be associated with the Middle Preclassic period (900-400 bc). If correct, human occupation of the site during the Preclassic period was more intense than previously known and volcanic eruptions must have affected prehistoric settlements. The archeological findings provide information on how prehistoric populations dealt with volcanic hazards, thousands of years ago in the eastern Zapotitán Valley, where several housing projects are currently being developed. The new stratigraphic and volcanological data can be used as a basis for local and regional hazard assessment related to future secondary vent activity in the San Salvador Volcanic Complex.

  9. Paleothermal structure of the Point San Luis slab of central California: Effects of Late Cretaceous underplating, out-of-sequence thrusting, and late Cenozoic dextral offset

    NASA Astrophysics Data System (ADS)

    Underwood, Michael B.; Laughland, Matthew M.

    2001-02-01

    Late Cretaceous shale and sandstone turbidites of the Point San Luis "slab" are isoclinally folded, locally sheared, and faulted, but their severity of stratal disruption is relatively mild when compared to adjacent polymictic mélange of the Franciscan Complex. We tested the interpretation of a trench-slope basin origin for these strata by documenting their paleothermal structure, including contacts between turbidites and mélange. Values of mean random vitrinite reflectance (Rm) from turbidites are 0.9-1.7% estimates of maximum paleotemperature are 135°-200°C. Mélange matrix samples yield Rm values of 1.1-2.5%, with an average of 1.5%, and peak temperatures between 160° and 240°C. The turbidite-over-mélange contact is locally "cooler over warmer" and was folded after peak heating. The relatively high paleotemperatures cast doubt on a shallow slope basin model (i.e., 1-2 km burial depth). We suggest, instead, that thermal maturation of the Point San Luis slab occurred much deeper in an accretionary prism (10-15 km), where offscraped trench wedge deposits were faulted against underplated mélange. The paleothermal structure was offset and tilted after peak heating by two out-of-sequence faults. Late Oligocene to Pliocene strata rest unconformably above the Franciscan, and there is a significant gap in thermal maturity across this unconformity, with no evidence to show that Franciscan rocks were reset thermally following the main episode of uplift and erosion. Three-dimensional orientations of isoreflectance surfaces on opposite sides of the San Gregorio-San Simeon-Hosgri fault system also can be used to test interpretations of strike-slip neotectonics. The failure to match these geometries among suspected piercing points at Point San Luis, Cambria, and Point Sur favors a suggestion that differential, post thermal peak, dextral offset of Franciscan basement has not exceeded 10-15 km.

  10. Cyanobacteria/Foraminifera Association from Anoxic/Dysoxic Beds of the Agua Nueva Formation (Upper Cretaceous - Cenomanian/Turonian) at Xilitla, San Luis Potosi, Central Mexico

    NASA Astrophysics Data System (ADS)

    Blanco-Piñón, A.; Maurrasse, F. J.; Rojas-León, A.; Duque-Botero, F.

    2008-05-01

    The Agua Nueva Formation in the vicinity of Xilitla, State of San Luis Potosí, Central Mexico, consists of interbedded brown shale (Grayish orange 10YR 7/4 to Moderate yellowish brown 10YR 5/4) and dark-gray fossiliferous limestone (Bluish gray 5B 6/1 to Dark bluish gray 5B 4/1), varying between 10 and 20 cm in thickness. The sequence also includes 2 to 4 cm- thick intermittent bentonite layers (Moderate greenish yellow 10Y 7/4, to dark greenish yellow 10Y 6/6 and Light olive 10Y 5/4). At the field scale, shaly intervals show no apparent internal structures, whereas most limestone beds show primary lamination at the millimeter scale (1-2 mm), and intermittent layers of black chert of about 5 cm thick. Pyrite is present as disseminated crystals and as 2 cm-thick layers. Bioturbation or macrobenthic organisms other than inoceramids do not occur in the Agua Nueva Formation at Xilitla. Unusual macrofossils are present only in limestone strata, and consist of well- preserved diverse genera of fishes such as sharks, Ptychodus sp. and teleosteans, Rhynchodercetis sp., Tselfatia sp., Goulmimichthys sp., and scales of Ichtyodectiformes, as well as ammonites and inoceramids (Blanco et al., 2006). The presence of Inoceramus (Mytyloides) labiatus (Maldonado-Koederll, 1956) indicates an Early Turonian age for the sequence. Total carbonate content (CaCO3 = TIC) varies between 62 and 94% in the Limestone beds, which yield Total Organic Carbon (TOC) from 0.4% to 2.5%; the shale intervals contain TIC values consistently lower than 33% and TOC lower than 0.8% Microscopically the limestone beds vary from mudstone to packstone composed essentially of coccoid cyanobacteria similar to coeval deposits in northeastern Mexico, Coahuila State, at Parras de La Fuente (Duque- Botero 2006). Similarly, the microspheroids are spherical to sub-spherical, and occur as isolated elements or aggregates forming series of chains of parallel-packed light lamina 1-2 mm thick. Filamentous cyanobacteria

  11. 27 CFR 9.171 - San Bernabe.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... San Bernabe viticultural area is located in central Monterey County, south of King City, California... benchmark 304, located one-half mile southwest of King City, along the Salinas River, in Township 20...

  12. Interior building details of Building A, dungeon central hallway: poured ...

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

    Interior building details of Building A, dungeon central hallway: poured concrete floors, plaster-finished brick walls, vaulted ceiling, arch entryway to cells; southerly view - San Quentin State Prison, Building 22, Point San Quentin, San Quentin, Marin County, CA

  13. A new Eimeria sP. from the plumbeous Central American caecilian, Dermophis mexicanus (amphibia: gymnophiona) from Volcán Tajumulco, Department of San Marcos, Guatemala.

    PubMed

    Asmundsson, I M; Campbell, J A; Duszynski, D W

    2000-04-01

    Fresh fecal samples from 5 caecilians (Dermophis mexicanus) were collected and examined for coccidia in the summer of 1998. The caecilians were collected in the Department of San Marcos, Guatemala. Two of the 5 (40%) specimens of caecilians contained an Eimeria species that is described here as new. This represents the first coccidia described from a gymnophionian host. Sporulated oocysts are spheroidal to subspheroidal, 19.5 X 17.7 (16-23 x 15-21) microm, micropyle and oocyst residuum are absent, and 3 (or more) polar granules are always present. Sporocysts are ovoidal, 11.0 X 7.2 (10-12 x 6-9); a Stieda body and sporocyst residuum are present.

  14. A new Eimeria sP. from the plumbeous Central American caecilian, Dermophis mexicanus (amphibia: gymnophiona) from Volcán Tajumulco, Department of San Marcos, Guatemala.

    PubMed

    Asmundsson, I M; Campbell, J A; Duszynski, D W

    2000-04-01

    Fresh fecal samples from 5 caecilians (Dermophis mexicanus) were collected and examined for coccidia in the summer of 1998. The caecilians were collected in the Department of San Marcos, Guatemala. Two of the 5 (40%) specimens of caecilians contained an Eimeria species that is described here as new. This represents the first coccidia described from a gymnophionian host. Sporulated oocysts are spheroidal to subspheroidal, 19.5 X 17.7 (16-23 x 15-21) microm, micropyle and oocyst residuum are absent, and 3 (or more) polar granules are always present. Sporocysts are ovoidal, 11.0 X 7.2 (10-12 x 6-9); a Stieda body and sporocyst residuum are present. PMID:10780555

  15. Central San Francisco Bay suspended-sediment transport processes and comparison of continuous and discrete measurements of suspended-solids concentrations

    USGS Publications Warehouse

    Schoellhamer, David H.

    1996-01-01

    Sediments are an important component of the San Francisco Bay estuarine system. Potentially toxic substances, such as metals and pesticides, adsorb to sediment particles (Kuwabara and others, 1989; Domagalski and Kuivila, 1993). Sediments on the bottom of the bay provide the habitat for benthic communities that can ingest these substances and introduce them into the food web (Luoma and others, 1985). Nutrients, metals, and other substances are stored in bottom sediments and pore water in which chemical reactions occur and which provide an important source and/or sink to the water column (Hammond and others, 1985; Flegal and others, 1991). The transport and fate of suspended sediment is an important factor in determining the transport and fate of the constituents adsorbed on the sediment. Seasonal changes in sediment erosion and deposition patterns contribute to seasonal changes in the abundance of benthic macroinvertebrates (Nichols and Thompson, 1985). Tidal marshes are an ecologically important habitat that were created and are maintained by sedimentation processes (Atwater and others, 1979). In Suisun Bay, the maximum suspended-sediment concentration marks the position of the turbidity maximum, which is a crucial ecological region in which suspended sediment, nutrients, phytoplankton, zooplankton, larvae, and juvenile fish accumulate (Peterson and others, 1975; Arthur and Ball, 1979; Kimmerer, 1992; Jassby and Powell, 1994). Suspended sediments confine the photic zone to the upper part of the water column, and this limitation on light availability is a major control on phytoplankton production in San Francisco Bay (Cloern, 1987; Cole and Cloern, 1987). Suspended sediments also deposit in ports and shipping channels, which must be dredged to maintain navigation (U.S. Environmental Protection Agency, 1992).

  16. Olmec civilization, veracruz, Mexico: dating of the san lorenzo phase.

    PubMed

    Coe, M D; Diehl, R A; Stuiver, M

    1967-03-17

    Archeological excavations at San Lorenzo Tenochtitlan, Veracruz, show that the Olmec sculptures of this zone are associated with the San Lorenzo phase, which can be placed in the Early Formative period (1500-800 B.C.) on the basis of ceramic comparisons. Five of six radiocarbon dates for the San Lorenzo phase fall within the 1200-900 B.C. span. The San Lorenzo phase therefore marks the beginning of Olmec civilization, and the sites forming the San Lorenzo Tenochtitlan group represent the oldest civilized communities known in Mexico or Central America.

  17. Flow characteristics of streams that drain the Fort Apache and San Carlos Indian reservations, east-central Arizona, 1930-86

    USGS Publications Warehouse

    Baldys, Stanley; Bayles, J.A.

    1990-01-01

    Streamflow characteristics of the Salt River and Gila River basins in the Fort Apache and San Carlos Indian Reservations, were studied in response to pending adjudication of water resources in those basins. Statistical summaries were compiled for 28 streamflow-gaging stations in and near the reservation. Mean annual streamflow for 1930-86 was computed for stations with complete records for the period; for those stations with records that did not completely cover the 1930-86 period, record extension techniques were used. Mean annual streamflow for ungaged sites on streams with gaging stations was estimated by interpolation between data points using drainage-area ratios. Two regional-regression equations were derived to estimate mean annual streamflow at sites on ungaged natural streams. The standard error of the regression for estimation of mean annual flow for sites in the Salt River basin is -37 to +59%. The standard error of the regression for estimation of mean annual flow for sites in the Gila River basins is -18 to +21%. (USGS)

  18. The unrest of the San Miguel volcano (El Salvador, Central America): installation of the monitoring network and observed volcano-tectonic ground deformation

    NASA Astrophysics Data System (ADS)

    Bonforte, Alessandro; Hernandez, Douglas Antonio; Gutiérrez, Eduardo; Handal, Louis; Polío, Cecilia; Rapisarda, Salvatore; Scarlato, Piergiorgio

    2016-08-01

    On 29 December 2013, the Chaparrastique volcano in El Salvador, close to the town of San Miguel, erupted suddenly with explosive force, forming a column more than 9 km high and projecting ballistic projectiles as far as 3 km away. Pyroclastic density currents flowed to the north-northwest side of the volcano, while tephras were dispersed northwest and north-northeast. This sudden eruption prompted the local Ministry of Environment to request cooperation with Italian scientists in order to improve the monitoring of the volcano during this unrest. A joint force, made up of an Italian team from the Istituto Nazionale di Geofisica e Vulcanologia and a local team from the Ministerio de Medio Ambiente y Recursos Naturales, was organized to enhance the volcanological, geophysical and geochemical monitoring system to study the evolution of the phenomenon during the crisis. The joint team quickly installed a multiparametric mobile network comprising seismic, geodetic and geochemical sensors (designed to cover all the volcano flanks from the lowest to the highest possible altitudes) and a thermal camera. To simplify the logistics for a rapid installation and for security reasons, some sensors were colocated into multiparametric stations. Here, we describe the prompt design and installation of the geodetic monitoring network, the processing and results. The installation of a new ground deformation network can be considered an important result by itself, while the detection of some crucial deforming areas is very significant information, useful for dealing with future threats and for further studies on this poorly monitored volcano.

  19. Emission of gas and atmospheric dispersion of SO2 during the December 2013 eruption at San Miguel volcano (El Salvador, Central America)

    NASA Astrophysics Data System (ADS)

    Granieri, Domenico; Salerno, Giuseppe; Liuzzo, Marco; La Spina, Alessandro; Giuffrida, Giovanni; Caltabiano, Tommaso; Giudice, Gaetano; Gutierrez, Eduardo; Montalvo, Francisco; Burton, Michael R.; Papale, Paolo

    2015-07-01

    San Miguel volcano, El Salvador, erupted on 29 December 2013, after a 46 year period characterized by weak activity. Prior to the eruption a trend of increasing SO2 emission rate was observed, with all values measured after mid-November greater than the average value of the previous year (~310 t d-1). During the eruption, SO2 emissions increased from the level of ~330 t d-1 to 2200 t d-1, dropping after the eruption to an average level of 680 t d-1. Wind measurements and SO2 emission rates during the preeruptive, syneruptive, and posteruptive stages were used to model SO2 dispersion around the volcano. Atmospheric SO2 concentration exceeded the dangerous threshold of 5 ppm in the crater region and in some sectors with medium elevation of the highly visited volcanic cone. Combining the SO2 emission rate with measured CO2/SO2, HCl/SO2, and HF/SO2 plume gas ratios, we estimate the CO2, HCl, and HF outputs for the first time on this volcano.

  20. Relations of hydrogeologic factors, groundwater reduction-oxidation conditions, and temporal and spatial distributions of nitrate, Central-Eastside San Joaquin Valley, California, USA

    NASA Astrophysics Data System (ADS)

    Landon, Matthew K.; Green, Christopher T.; Belitz, Kenneth; Singleton, Michael J.; Esser, Bradley K.

    2011-09-01

    In a 2,700-km2 area in the eastern San Joaquin Valley, California (USA), data from multiple sources were used to determine interrelations among hydrogeologic factors, reduction-oxidation (redox) conditions, and temporal and spatial distributions of nitrate (NO3), a widely detected groundwater contaminant. Groundwater is predominantly modern, or mixtures of modern water, with detectable NO3 and oxic redox conditions, but some zones have anoxic or mixed redox conditions. Anoxic conditions were associated with long residence times that occurred near the valley trough and in areas of historical groundwater discharge with shallow depth to water. Anoxic conditions also were associated with interactions of shallow, modern groundwater with soils. NO3 concentrations were significantly lower in anoxic than oxic or mixed redox groundwater, primarily because residence times of anoxic waters exceed the duration of increased pumping and fertilizer use associated with modern agriculture. Effects of redox reactions on NO3 concentrations were relatively minor. Dissolved N2 gas data indicated that denitrification has eliminated >5 mg/L NO3-N in about 10% of 39 wells. Increasing NO3 concentrations over time were slightly less prevalent in anoxic than oxic or mixed redox groundwater. Spatial and temporal trends of NO3 are primarily controlled by water and NO3 fluxes of modern land use.

  1. Distribution of reduction-oxidation conditions and relation to trends in nitrate in groundwater, Central-Eastside San Joaquin Valley, California

    NASA Astrophysics Data System (ADS)

    Landon, M. K.; Green, C. T.; Belitz, K.

    2010-12-01

    A 2,700 km2 study area in the eastern San Joaquin Valley near Modesto, California, was investigated to: describe three-dimensional reduction-oxidation (redox) conditions by using water chemistry data compiled from multiple sources; analyze relations of redox conditions to explanatory factors; and determine relations between nitrate (NO3) trends and redox conditions and other factors. Redox conditions are primarily oxic, but increasingly anoxic conditions were correlated with proximity to the valley center, decreased depth to water, and areas of historical groundwater discharge. Anoxic conditions in areas with shallow depths to water occur in both modern recharge, which has abundant organic carbon as an electron donor due to interactions of the shallow water table with soils, and pre-modern groundwater in discharge areas. Although NO3 concentrations were significantly less in wells with anoxic than oxic or mixed redox conditions, dissolved N2 gas data from 39 wells indicate that denitrification caused NO3 concentrations to decrease from above to below the drinking water threshold in only 1 well (maximum excess N2-N of 11 mg/L), indicating that denitrification does not currently protect many wells from NO3 contamination. Trends in NO3 concentrations showed only minor relations to redox conditions. Although NO3 concentrations and trends in the study area are primarily controlled by loading from agricultural land use rather than by redox conditions, greater understanding of the factors controlling the distribution of redox conditions contributes to efforts to simulate NO3 transport at a regional scale.

  2. Relations of hydrogeologic factors, groundwater reduction-oxidation conditions, and temporal and spatial distributions of nitrate, Central-Eastside San Joaquin Valley, California, USA

    USGS Publications Warehouse

    Landon, M.K.; Green, C.T.; Belitz, K.; Singleton, M.J.; Esser, B.K.

    2011-01-01

    In a 2,700-km2 area in the eastern San Joaquin Valley, California (USA), data from multiple sources were used to determine interrelations among hydrogeologic factors, reduction-oxidation (redox) conditions, and temporal and spatial distributions of nitrate (NO3), a widely detected groundwater contaminant. Groundwater is predominantly modern, or mixtures of modern water, with detectable NO3 and oxic redox conditions, but some zones have anoxic or mixed redox conditions. Anoxic conditions were associated with long residence times that occurred near the valley trough and in areas of historical groundwater discharge with shallow depth to water. Anoxic conditions also were associated with interactions of shallow, modern groundwater with soils. NO3 concentrations were significantly lower in anoxic than oxic or mixed redox groundwater, primarily because residence times of anoxic waters exceed the duration of increased pumping and fertilizer use associated with modern agriculture. Effects of redox reactions on NO3 concentrations were relatively minor. Dissolved N2 gas data indicated that denitrification has eliminated gt;5 mg/L NO3-N in about 10% of 39 wells. Increasing NO3 concentrations over time were slightly less prevalent in anoxic than oxic or mixed redox groundwater. Spatial and temporal trends of NO3 are primarily controlled by water and NO3 fluxes of modern land use. ?? 2011 Springer-Verlag (outside the USA).

  3. Relations of hydrogeologic factors, groundwater reduction-oxidation conditions, and temporal and spatial distributions of nitrate, Central-Eastside San Joaquin Valley, California, USA

    USGS Publications Warehouse

    Landon, Matthew K.; Green, Christopher T.; Belitz, Kenneth; Singleton, Michael J.; Esser, Bradley K.

    2011-01-01

    In a 2,700-km2 area in the eastern San Joaquin Valley, California (USA), data from multiple sources were used to determine interrelations among hydrogeologic factors, reduction-oxidation (redox) conditions, and temporal and spatial distributions of nitrate (NO3), a widely detected groundwater contaminant. Groundwater is predominantly modern, or mixtures of modern water, with detectable NO3 and oxic redox conditions, but some zones have anoxic or mixed redox conditions. Anoxic conditions were associated with long residence times that occurred near the valley trough and in areas of historical groundwater discharge with shallow depth to water. Anoxic conditions also were associated with interactions of shallow, modern groundwater with soils. NO3 concentrations were significantly lower in anoxic than oxic or mixed redox groundwater, primarily because residence times of anoxic waters exceed the duration of increased pumping and fertilizer use associated with modern agriculture. Effects of redox reactions on NO3 concentrations were relatively minor. Dissolved N2 gas data indicated that denitrification has eliminated >5 mg/L NO3–N in about 10% of 39 wells. Increasing NO3 concentrations over time were slightly less prevalent in anoxic than oxic or mixed redox groundwater. Spatial and temporal trends of NO3 are primarily controlled by water and NO3 fluxes of modern land use.

  4. Geochemical, petrographic and physical characterizations and associated alterations of the volcanic rocks of the Romanesque San Nicola Church (Ottana, central Sardinia, Italy)

    NASA Astrophysics Data System (ADS)

    Columbu, Stefano; Palomba, Marcella; Sitzia, Fabio

    2015-04-01

    In this research, the volcanic rocks belonging to the Sardinia Oligo-Miocene volcanic cycle (32 - 11 Ma) and building up the structure of the San Nicola church, one of the most representative churches of the Romanesque architecture, were studied. These stones were widely used in medieval architecture for the excellent workability, but they present some disadvantages, since they are greatly affected by alteration phenomena. The main objectives of this research are i) to focus the mineral, chemical and petrographic compositions of the San Nicola stones, ii) the chemical and physical alteration processes affecting these materials, and iii) to establish the exactly provenance of the volcanic rocks. Furthermore, a comparative study between the rocks from the ancient quarries and those forming the structure of the church was performed. In the ancient quarries, where presumably a more advanced alteration occurs due to the vertical alteration gradient, different facies of the same volcanic lithology, characterized by macroscopical evidences of chemical-physical degradation degree, were sampled. Petrographic, geochemical (both major elements that the traces) and physical-mechanical features of the collected samples were determined to highlight the compositional differences (density, porosity, water-absorption kinetics, mechanical resistance) as a function of the different alteration degree. Moreover, chemical-mineralogical analysis of the sample surfaces from the church, was performed, to highlight possible presence and nature of secondary newly-formed phases (e.g., salt efflorescence). Several methodologies were applied to carry out physical-chemical and petrographic analysis: X-Ray fluorescence (XRF) and Inductively Coupled Mass Spectrometry (ICP-MS), X-Ray Diffractometry (XRD) for chemical and mineral composition; Optical and Scanning Electron Microscopy (SEM) for textures, mineral assemblages and microstructures studies; He-picnometry, water-absorption and mechanical

  5. Morphotectonic and neotectonic control on river pattern in the Sierra de la Cantera piedmont, Central Precordillera, province of San Juan, Argentina

    NASA Astrophysics Data System (ADS)

    Perucca, Laura P.; Rothis, Martín; Vargas, Horacio N.

    2014-01-01

    The drainage pattern on the western piedmont of the Sierra de La Cantera is divergent, typical of alluvial fans and showing anomalies that are directly related to the trace of La Cantera thrust. In previous studies, two types of anomalies were identified: upstream of the fault scarp, rivers have a broom-shaped pattern, while downstream - in the hanging block - streams become denser, more sinuous and incised. In this contribution, these morphotectonic aspects were analyzed in detail, making direct and indirect analysis to quantify the relationship between these anomalies and the faults affecting alluvial fans. In addition, the influence of neotectonic activity on smaller water course patterns in the alluvial fan areas was investigated in order to find indicators of on-going vertical movements, since the spatial arrangements of these piedmont channels are determined by slope and structure, where active faults cause diversions or anomalies. Topographic profiles in two selected channels cutting across the trace of the fault were performed using a differential GPS in order to establish the relationship between the sinuosity and slope of these rivers. The results obtained allow us to state that the most sinuous channels have lower slopes and are located in the hanging wall of the fault. Morphometric analysis of scarps stated that active tectonics have played an essential role in controlling the drainage pattern in the piedmont, leading the rivers to adjust to these slope variations. Finally, based on the geomorphologic, stratigraphic, structural and seismological characteristics and parameters analyzed, La Cantera Thrust is considered a seismogenic source of significance to the nearby towns (> 700,000 inhabitants) and also to the large-scale dams built downstream along the San Juan River.

  6. LiDAR and field observations of slip distribution for the most recent surface ruptures along the central San Jacinto fault

    USGS Publications Warehouse

    J.B. Salisbury,; T.K. Rockwell,; T.J. Middleton,; Hudnut, Kenneth W.

    2012-01-01

    We measured offsets on tectonically displaced geomorphic features along 80 km of the Clark strand of the San Jacinto fault (SJF) to estimate slip‐per‐event for the past several surface ruptures. We identify 168 offset features from which we make over 490 measurements using B4 light detection and ranging (LiDAR) imagery and field observations. Our results suggest that LiDAR technology is an exemplary supplement to traditional field methods in slip‐per‐event studies. Displacement estimates indicate that the most recent surface‐rupturing event (MRE) produced an average of 2.5–2.9 m of right‐lateral slip with maximum slip of nearly 4 m at Anza, a Mw 7.2–7.5 earthquake. Average multiple‐event offsets for the same 80 kms are ∼5.5  m, with maximum values of 3 m at Anza for the penultimate event. Cumulative displacements of 9–10 m through Anza suggest the third event was also similar in size. Paleoseismic work at Hog Lake dates the most recent surface rupture event at ca. 1790. A poorly located, large earthquake occurred in southern California on 22 November 1800; we relocate this event to the Clark fault based on the MRE at Hog Lake. We also recognize the occurrence of a younger rupture along ∼15–20  km of the fault in Blackburn Canyon with ∼1.25  m of average displacement. We attribute these offsets to the 21 April 1918 Mw 6.9 event. These data argue that much or all of the Clark fault, and possibly also the Casa Loma fault, fail together in large earthquakes, but that shorter sections may fail in smaller events.

  7. The Purisima Formation and related rocks (upper Miocene - Pliocene), greater San Francisco Bay area, central California; review of literature and USGS collection now housed at the Museum of Paleontology, University of California, Berkeley

    USGS Publications Warehouse

    Powell, C.L.

    1998-01-01

    Sedimentary rocks more than 1.6 kilometers thick are attributed to the upper Miocene to upper Pliocene Purisima Formation in the greater San Francisco Bay area. These rocks occur as scattered, discontinuous outcrops from Point Reyes National Seashore in the north to south of Santa Cruz. Lithologic divisions of the Formation appear to be of local extent and are of limited use in correlating over this broad area. The Purisima Formation occurs in several fault-bounded terranes which demonstrate different stratigraphic histories and may be found to represent more than a single depositional basin. The precise age and stratigraphic relationship of these scattered outcrops are unresolved and until they are put into a stratigraphic and paleogeographic context the tectonic significance of the Purisima Foramtion can only be surmised. This paper will attempt to resolve some of these problems. Mollusks and echinoderms are recorded from the literature and more than 70 USGS collections that have not previously been reported. With the exception of one locality, the faunas suggest deposition in normal marine conditions at water depths of less than 50 m and with water temperatures the same or slightly cooler than exist along the present coast of central California. The single exception is a fauna from outcrops between Seal Cove and Pillar Point, where both mollusks and foraminifers suggest water depths greater than 100 m. Three molluscan faunas, the La Honda, the Pillar Point, and the Santa Cruz, are recognized based on USGS collections and published literature for the Purisima Formation. These biostratigraphically distinct faunas aid in the correlation of the scattered Purisima Formation outcrops. The lowermost La Honda fauna suggests shallow-water depths and an age of late Miocene to early Pliocene. This age is at odds with a younger age determination from an ash bed in the lower Purisima Formation along the central San Mateo County coast. The Pillar Point fauna contains only a

  8. 409. Delineator Unknown October 25, 1933 (SAN FRANCISCO ANCHORAGE); SAN ...

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

    409. Delineator Unknown October 25, 1933 (SAN FRANCISCO ANCHORAGE); SAN FRANCISCO - OAKLAND BAY BRIDGE; BOARD OF CONSULTING ARCHITECTS; TIMOTHY L. PFLUEGER, ARTHUR BROWN JR., JOHN J. DONOVAN; DRAWING NO.33 - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  9. Planned updates and refinements to the central valley hydrologic model, with an emphasis on improving the simulation of land subsidence in the San Joaquin Valley

    USGS Publications Warehouse

    Faunt, C.C.; Hanson, R.T.; Martin, P.; Schmid, W.

    2011-01-01

    California's Central Valley has been one of the most productive agricultural regions in the world for more than 50 years. To better understand the groundwater availability in the valley, the U.S. Geological Survey (USGS) developed the Central Valley hydrologic model (CVHM). Because of recent water-level declines and renewed subsidence, the CVHM is being updated to better simulate the geohydrologic system. The CVHM updates and refinements can be grouped into two general categories: (1) model code changes and (2) data updates. The CVHM updates and refinements will require that the model be recalibrated. The updated CVHM will provide a detailed transient analysis of changes in groundwater availability and flow paths in relation to climatic variability, urbanization, stream flow, and changes in irrigated agricultural practices and crops. The updated CVHM is particularly focused on more accurately simulating the locations and magnitudes of land subsidence. The intent of the updated CVHM is to help scientists better understand the availability and sustainability of water resources and the interaction of groundwater levels with land subsidence. ?? 2011 ASCE.

  10. Planned updates and refinements to the Central Valley hydrologic model with an emphasis on improving the simulation of land subsidence in the San Joaquin Valley

    USGS Publications Warehouse

    Faunt, Claudia C.; Hanson, Randall T.; Martin, Peter; Schmid, Wolfgang

    2011-01-01

    California's Central Valley has been one of the most productive agricultural regions in the world for more than 50 years. To better understand the groundwater availability in the valley, the U.S. Geological Survey (USGS) developed the Central Valley hydrologic model (CVHM). Because of recent water-level declines and renewed subsidence, the CVHM is being updated to better simulate the geohydrologic system. The CVHM updates and refinements can be grouped into two general categories: (1) model code changes and (2) data updates. The CVHM updates and refinements will require that the model be recalibrated. The updated CVHM will provide a detailed transient analysis of changes in groundwater availability and flow paths in relation to climatic variability, urbanization, stream flow, and changes in irrigated agricultural practices and crops. The updated CVHM is particularly focused on more accurately simulating the locations and magnitudes of land subsidence. The intent of the updated CVHM is to help scientists better understand the availability and sustainability of water resources and the interaction of groundwater levels with land subsidence.

  11. Water level, specific conductance, and water temperature data, San Francisco Bay, California, for Water Year 2000

    USGS Publications Warehouse

    Buchanan, P.A.

    2002-01-01

    Time series of water-level, specific-conductance, and watertemperature data were collected at seven sites in San Francisco Bay during water year 2000 (October 1, 1999 through September 30, 2000). Water-level data were recorded only at Point San Pablo. Specific-conductance and water-temperature data were recorded at 15-minute intervals at the following locations (Figure 1): • Carquinez Strait at Carquinez Bridge • Napa River at Mare Island Causeway near Vallejo • San Pablo Bay at Petaluma River Channel Marker 9 • San Pablo Strait at Point San Pablo • Central San Francisco Bay at Presidio Military Reservation • Central San Francisco Bay at Pier 24 • South San Francisco Bay at San Mateo Bridge near Foster City.

  12. Marine terrace deformation, san diego county, California

    USGS Publications Warehouse

    McCrory, P.A.; Lajoie, K.R.

    1979-01-01

    The NW-SE trending southern California coastline between the Palos Verdes Peninsula and San Diego roughly parallels the southern part and off-shore extension of the dominantly right-lateral, strike-slip, Newport-Inglewood fault zone. Emergent marine terraces between Newport Bay and San Diego record general uplift and gentle warping on the northeast side of the fault zone throughout Pleistocene time. Marine terraces on Soledad Mt. and Point Loma record local differential uplift (maximum 0.17 m/ka) during middle to late Pleistocene time on the southwest side of the fault (Rose Canyon fault) near San Diego. The broad Linda Vista Mesa (elev. 70-120 m) in the central part of coastal San Diego County, previously thought to be a single, relatively undeformed marine terrace of Plio-Pleistocene age, is a series of marine terraces and associated beach ridges most likely formed during sea-level highstands throughout Pleistocene time. The elevations of the terraces in this sequence gradually increase northwestward to the vicinity of San Onofre, indicating minor differential uplift along the central and northern San Diego coast during Pleistocene time. The highest, oldest terraces in the sequence are obliterated by erosional dissection to the northwest where uplift is greatest. Broad, closely spaced (vertically) terraces with extensive beach ridges were the dominant Pleistocene coastal landforms in central San Diego County where the coastal slope is less than 1% and uplift is lowest. The beach ridges die out to the northwest as the broad low terraces grade laterally into narrower, higher, and more widely spaced (vertically) terraces on the high bluffs above San Onofre where the coastal slope is 20-30% and uplift is greatest. At San Onofre the terraces slope progressively more steeply toward the ocean with increasing elevation, indicating continuous southwest tilt accompanying uplift from middle to late Pleistocene time. This southwest tilt is also recorded in the asymmetrical

  13. 8. VIEW LOOKING NORTHWEST DOWN CENTRAL AXIS OF ROOM 110. ...

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

    8. VIEW LOOKING NORTHWEST DOWN CENTRAL AXIS OF ROOM 110. NOTE CHANGE IN CEILING TREATMENT: WOOD PLANKS IN CENTER, ALL OTHER AREAS ARE GYPSUM BOARD. FLOOR IN CENTRAL AREA IS CONCRETE. POSTS AND BEAMS ARE ALL WOOD CONSTRUCTION. - Presidio of San Francisco, Cavalry Stables, Cowles Street, between Lincoln Boulevard & McDowell Street, San Francisco, San Francisco County, CA

  14. Specific conductance, water temperature, and water level data, San Francisco Bay, California, water year 1998

    USGS Publications Warehouse

    Buchanan, Paul A.

    1999-01-01

    Specific conductance and water temperature data are continuously recorded at four sites in San Francisco Bay, California: San Pablo Strait at Point San Pablo, Central San Francisco Bay at Presidio Military Reservation, Pier 24 at Bay Bridge, and South San Francisco Bay at San Mateo Bridge near Foster City (Figure 1). Water level data are recorded only at San Pablo Strait at Point San Pablo. These data were recorded by the Department of Water Resources (DWR) before 1988, by the US Geological Survey (USGS) National Research Program from 1988 to 1989, and by the USGS-DWR cooperative program since 1990. This article presents time-series plots of data from the four sites in San Francisco Bay during water year 1998 (1 October 1997 through 30 September 1998).

  15. 40. Historic American Buildings Survey San Francisco Chronicle Collection San ...

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

    40. Historic American Buildings Survey San Francisco Chronicle Collection San Francisco, California March 24, 1924 VIEW OF HIGH ALTAR - Mission San Carlos Borromeo, Rio Road & Lausen Drive, Carmel-by-the-Sea, Monterey County, CA

  16. San Francisco floating STOLport study

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The operational, economic, environmental, social and engineering feasibility of utilizing deactivated maritime vessels as a waterfront quiet short takeoff and landing facility to be located near the central business district of San Francisco was investigated. Criteria were developed to evaluate each site, and minimum standards were established for each criterion. Predicted conditions at the two sites were compared to the requirements for each of the 11 criteria as a means of evaluating site performance. Criteria include land use, community structure, economic impact, access, visual character, noise, air pollution, natural environment, weather, air traffic, and terminal design.

  17. 78 FR 53243 - Safety Zone; TriRock San Diego, San Diego Bay, San Diego, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-29

    ... Acronyms DHS Department of Homeland Security FR Federal Register NPRM Notice of Proposed Rulemaking A... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; TriRock San Diego, San Diego Bay, San Diego... temporary safety zone upon the navigable waters of the San Diego Bay, San Diego, CA, in support of...

  18. 77 FR 54811 - Safety Zone; TriRock San Diego, San Diego Bay, San Diego, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-06

    .... SUPPLEMENTARY INFORMATION: Table of Acronyms DHS Department of Homeland Security FR Federal Register NPRM Notice... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; TriRock San Diego, San Diego Bay, San Diego... safety zone upon the navigable waters of the San Diego Bay, San Diego, CA, in support of a bay swim...

  19. 24. INTERIOR OF CENTRAL ROOM. BASE POWER PANEL VISIBLE ON ...

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

    24. INTERIOR OF CENTRAL ROOM. BASE POWER PANEL VISIBLE ON RIGHT WALL OF HALLWAY. - Chollas Heights Naval Radio Transmitting Facility, Transmitter Building, 6410 Zero Road, San Diego, San Diego County, CA

  20. SAN CARLOS APACHE PAPERS.

    ERIC Educational Resources Information Center

    ROESSEL, ROBERT A., JR.

    THE FIRST SECTION OF THIS BOOK COVERS THE HISTORICAL AND CULTURAL BACKGROUND OF THE SAN CARLOS APACHE INDIANS, AS WELL AS AN HISTORICAL SKETCH OF THE DEVELOPMENT OF THEIR FORMAL EDUCATIONAL SYSTEM. THE SECOND SECTION IS DEVOTED TO THE PROBLEMS OF TEACHERS OF THE INDIAN CHILDREN IN GLOBE AND SAN CARLOS, ARIZONA. IT IS DIVIDED INTO THREE PARTS--(1)…

  1. San Cristobal Volcano, Nicaragua

    NASA Technical Reports Server (NTRS)

    1990-01-01

    A white plume of smoke, from San Cristobal Volcano (13.0N, 87.5W) on the western coast of Nicaragua, blows westward along the Nicaraguan coast just south of the Gulf of Fonseca and the Honduran border. San Csistobal is a strato volcano some 1,745 meters high and is frequently active.

  2. California: San Joaquin Valley

    Atmospheric Science Data Center

    2014-05-15

    article title:  Fog and Haze in California's San Joaquin Valley   ... is noted for its hazy overcasts and a low, thick ground fog known as the Tule. Owing to the effects of the atmosphere on reflected ... as the angle of view changes. An area of thick, white fog in the San Joaquin Valley is visible in all three of the images. However, ...

  3. Geophysical evidence for wedging in the San Gorgonio Pass structural knot, southern San Andreas fault zone, southern California

    USGS Publications Warehouse

    Langenheim, V.E.; Jachens, R.C.; Matti, J.C.; Hauksson, E.; Morton, D.M.; Christensen, A.

    2005-01-01

    Geophysical data and surface geology define intertonguing thrust wedges that form the upper crust in the San Gorgonio Pass region. This picture serves as the basis for inferring past fault movements within the San Andreas system, which are fundamental to understanding the tectonic evolution of the San Gorgonio Pass region. Interpretation of gravity data indicates that sedimentary rocks have been thrust at least 5 km in the central part of San Gorgonio Pass beneath basement rocks of the southeast San Bernardino Mountains. Subtle, long-wavelength magnetic anomalies indicate that a magnetic body extends in the subsurface north of San Gorgonio Pass and south under Peninsular Ranges basement, and has a southern edge that is roughly parallel to, but 5-6 km south of, the surface trace of the Banning fault. This deep magnetic body is composed either of upper-plate rocks of San Gabriel Mountains basement or rocks of San Bernardino Mountains basement or both. We suggest that transpression across the San Gorgonio Pass region drove a wedge of Peninsular Ranges basement and its overlying sedimentary cover northward into the San Bernardino Mountains during the Neogene, offsetting the Banning fault at shallow depth. Average rates of convergence implied by this offset are broadly consistent with estimates of convergence from other geologic and geodetic data. Seismicity suggests a deeper detachment surface beneath the deep magnetic body. This interpretation suggests that the fault mapped at the surface evolved not only in map but also in cross-sectional view. Given the multilayered nature of deformation, it is unlikely that the San Andreas fault will rupture cleanly through the complex structures in San Gorgonio Pass. ?? 2005 Geological Society of America.

  4. Plankton studies in San Francisco Bay; II, Phytoplankton abundance and species composition, July 1977-December 1979

    USGS Publications Warehouse

    Wong, Raymond L. J.; Cloern, James E.

    1981-01-01

    Data are presented on the phytoplankton species composition and abundance in San Francisco Bay from July 1977 through December 1979. Phytoplankton identification and enumerations were made at selected stations. Sample collections were made at selected stations in the main channel of the Bay from Rio Vista on the Sacramento River to Calaveras Point in South San Francisco Bay, and at shoal stations in the central portion of South San Francisco Bay, San Pablo Bay, and Suisun Bay. Also reported, from October 1978 through December 1979, are the calculated phytoplankton carbon and percent nondiatom carbon, and the species list. This study is one component of an ongoing interdisciplinary study of San Francisco Bay. (USGS)

  5. Photocopy of drawing located at National Archives, San Bruno, California ...

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

    Photocopy of drawing located at National Archives, San Bruno, California (Navy # 121-A-15). Building 121 sta-b central power plant switch gear and office annex elevations; July, 1942. - Mare Island Naval Shipyard, Central Power Plant, California Avenue, norhtwest corner of California Avenue & Seventh Street, Vallejo, Solano County, CA

  6. Neogene geomorphic and climatic evolution of the central San Juan Mountains, Colorado: K/Ar age and stable isotope data on supergene alunite and jarosite from the Creede mining district

    USGS Publications Warehouse

    Rye, Robert O.; Bethke, Philip M.; Lanphere, Marvin A.; Steven, Thomas A.

    2000-01-01

    K/Ar age determinations or supergene alunite and jarosite, formed during Neogene weathering of the epithermal silver and base-metal ores of the Creede mining district, have been combined with geologic evidence to estimate the timing of regional uplift of the southern Rocky Mountains and related canyon cutting. In addition, oxygen and hydrogen isotopic studies suggest climate changes in the central San Juan Mountains during the past 5 m.y. Alunite [ideally (K,Na)Al3(SO4)2(OH)6] and jarosite [ideally KFe3(SO4)2(OH)6] can be dated by K/Ar or 40Ar/39Ar techniques and both contain OH and SO4 sites that enable four stable isotope analyses (δD, δ18OOH, and δ34S) to be made. This supergene alunite and jarosite formed by weathering of sulfide-rich ore bodies may record the evolution of the chemical and hydrologic processes affecting ancient oxidized acid ground water, as well as details of climate history and geomorphic evolution. Fine-grained (1-10 μm) supergene alunite and jarosite occur in minor fractures in the upper, oxidized parts of the 25 Ma sulfide-bearing veins of the Creede mining district, and jarosite also occurs in adjacent oxidized Ag-bearing clastic sediments. K/Ar ages for alunite range from 4.8 to 3.1 Ma, and for jarosite range from 2.6 to 0.9 Ma. The δD values for alunite and jarosite show opposite correlations with elevation, and values for jarosite correlate with age. Calculated δDH2O values of alunite fluids approach but are larger than those of present-day meteoric water. Calculated δDH2O values for jarosite fluids are more variable; the values of the youngest jarosites are lowest and are similar to those of present-day meteoric water in the district. The narrow δD-δ18OSO4 values of alunites reflects oxidation of sulfide below the water table. The greater range in these values for jarosites reflects oxidation of sulfide under vadose conditions. The ages of alunite mark the position of the paleo-water table at the end of a period of moderate

  7. SAN JOAQUIN ROADLESS AREA, CALIFORNIA.

    USGS Publications Warehouse

    McKee, Edwin H.; Capstick, Donald O.

    1984-01-01

    The San Joaquin Roadless Area is composed of three noncontiguous areas on the eastern side of the Sierra Nevada in Madera County, California. The results of geologic, geochemical, and mining-activity and production surveys in the central part of the area indicate little promise for the occurrence of metallic-mineral or energy resources in the area. Sand, gravel, and pumice exist in the area but occurrences are small and isolated and farther from major markets than similar deposits outside the roadless area. Rocks in the area are exhibited in exposures of unaltered and nonmineralized granitic and metavolcanic rock along the steep western wall of the glacially carved valley of the Middle Fork of the San Joaquin River. Drainage in the area consists of seeps along fractures in the cliff or small cascading streams, a hydraulic setting not favorable for the development of placer deposits. No mines or prospect workings were found in the roadless area. Alteration zones within the granitic and metamorphic rock that crop out within the area are small, isolated, and consist only of limonitic staining and bleached quartzose rock.

  8. 16. OVERALL VIEW TO THE NORTH OVER THE CENTRAL PART ...

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

    16. OVERALL VIEW TO THE NORTH OVER THE CENTRAL PART OF THE INTERIOR, RECENTLY USED FOR A BASKETBALL, LOOKING NORTH TOWARDS THE ROLL-UP DOOR. - U.S. Coast Guard Air Station San Francisco, Warehouse, 1020 North Access Road, San Francisco, San Francisco County, CA

  9. 2. Historic American Buildings Survey San Francisco Chronicle Library San ...

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

    2. Historic American Buildings Survey San Francisco Chronicle Library San Francisco, California Year Built: 1834 Photo Taken: About 1925 VIEW FROM EAST - General Sherman Quarters, 464 Calle Principal, Monterey, Monterey County, CA

  10. Water-quality assessment of the Rio Grande Valley, Colorado, New Mexico, and Texas; shallow ground-water quality of a land-use area in the San Luis Valley, south-central Colorado, 1993

    USGS Publications Warehouse

    Anderholm, S.K.

    1996-01-01

    This report describes the quality of shallow ground water in an agricultural area in the San Luis Valley, Colorado, and discusses how natural and human factors affect the quality of shallow ground water. Thirty-five wells were installed, and water samples were collected from these wells and analyzed for selected dissolved common constituents, nutrients, trace elements, radionuclides, and synthetic organic compounds. The San Luis Valley is a high intermontane valley that is partially drained by the Rio Grande. The San Luis Valley land-use study area was limited to a part of the valley where the depth to water is generally less than 25 feet. The area where the 35 monitor wells were installed was further limited to the part of the study area where center-pivot overhead sprinklers are used to irrigate crops. Precipitation, runoff from adjacent mountainous areas, and ground-water inflow from the adjacent mountainous areas are the main sources of water to the aquifers in the San Luis Valley. Discharge of water from the shallow, unconfined aquifer in the valley is mainly from evapotranspiration. The dominant land use in the San Luis Valley is agriculture, although nonirrigated land and residential land are interspersed with agricultural land. Alfalfa, native hay, barley, wheat, potatoes, and other vegetables are the main crops. Dissolved-solids concentrations in shallow ground water sampled ranged from 75 to 1,960 milligrams per liter. The largest median concentration of cations was for calcium, and the largest median concentration of anions was for bicarbonate in shallow ground water in the San Luis Valley. Calcium concentrations ranged from 7.5 to 300 milligrams per liter, and bicarbonate concentrations ranged from 28 to 451 milligrams per liter. Nitrite plus nitrate concentrations ranged from less than 0.1 to 58 milligrams per liter as N; water from 11 wells had nitrite plus nitrate concentrations greater than 10 milligrams per liter as N. With the exception of the

  11. History of San Marco

    NASA Technical Reports Server (NTRS)

    Caporale, A. J.

    1968-01-01

    A brief history is reported of the first San Marco project, a joint program of the United States and Italy. The Project was a three phase effort to investigate upper air density and associated ionosphere phenomena. The initial phase included the design and development of the spacecraft, the experiments, the launch complex, and a series of suborbital flights, from Wallops Island. The second phase, consisting of designing, fabricating, and testing a spacecraft for the first orbital mission, culminated in an orbital launch also from Wallops Island. The third phase consisted of further refining the experiments and spacecraft instrumentation and of establishing a full-bore scout complex in Kenya. The launch of San Marco B, in April 1967, from this complex into an equatorial orbit, concluded the initial San Marco effort.

  12. New evidence on the state of stress of the san andreas fault system.

    PubMed

    Zoback, M D; Zoback, M L; Mount, V S; Suppe, J; Eaton, J P; Healy, J H; Oppenheimer, D; Reasenberg, P; Jones, L; Raleigh, C B; Wong, I G; Scotti, O; Wentworth, C

    1987-11-20

    Contemporary in situ tectonic stress indicators along the San Andreas fault system in central California show northeast-directed horizontal compression that is nearly perpendicular to the strike of the fault. Such compression explains recent uplift of the Coast Ranges and the numerous active reverse faults and folds that trend nearly parallel to the San Andreas and that are otherwise unexplainable in terms of strike-slip deformation. Fault-normal crustal compression in central California is proposed to result from the extremely low shear strength of the San Andreas and the slightly convergent relative motion between the Pacific and North American plates. Preliminary in situ stress data from the Cajon Pass scientific drill hole (located 3.6 kilometers northeast of the San Andreas in southern California near San Bernardino, California) are also consistent with a weak fault, as they show no right-lateral shear stress at approximately 2-kilometer depth on planes parallel to the San Andreas fault. PMID:17839366

  13. Diazinon concentrations in the Sacramento and San Joaquin Rivers and San Francisco Bay, California, February 1993

    USGS Publications Warehouse

    Kuivila, Kathryn M.

    1993-01-01

    The distribution and possible biological effects of a dormant spray pesticide, diazinon, were examined by measuring pesticide concentrations and estimating toxicity using bioassays at a series of sites in the Sacramento-San Joaquin Delta and San Francisco Bay. Pulses of diazinon were observed in early February 1993 in the Sacramento and San Joaquin Rivers after heavy rains, with elevated concentrations measured for a few days to weeks at a time. The pulse of diazinon in the Sacramento River was followed from Sacramento through Suisun Bay, the eastward embayment of San Francisco Bay. In the central delta, well-defined pulses of diazinon were not observed at the Old and Middle River sites; instead, the concentrations steadily increased throughout February. Ceriodaphnia dubia mortality was 100% in water samples collected for 12 consecutive days (February 8-19) from the San Joaquin River at Vernalis. The bioassay mortality corresponded with the peak diazinon concentrations. Conversely, no toxicity was observed in water collected before or after peaks of diazinon concentration. Other pesticides present also could contribute to the toxicity.

  14. Plankton studies in San Francisco Bay; IV, Phytoplankton abundance and species composition, January 1980 - February 1981

    USGS Publications Warehouse

    Wong, R.L.; Cloern, J.E.

    1982-01-01

    Data are presented on the phytoplankton species composition and abundance in San Francisco Bay from January 1980 through February 1981. Phytoplankton were identified and enumerated in surface samples collected approximately every two weeks at selected stations in the main channel of the Bay, and at shoal stations in the central portion of South San Francisco Bay, San Pablo Bay, and Suisun Bay. Also reported are separate species lists for microphytoplankton (< 60 micrometers) and macrophytoplankton (> 60 micrometers). (Author 's abstract)

  15. SAN PEDRO GEODATA BROWSER

    EPA Science Inventory

    The San Pedro Data Browser was developed by the Landscape Ecology Branch of the U.S. Environmental Protection Agency (Las Vegas, NV). The goal of the Landscape Sciences Program is to improve decision-making relative to natural and human resource management through the development...

  16. SAN PEDRO WATERSHED DATABASE

    EPA Science Inventory

    The San Pedro River Geo-Data Browser was jointly developed by the Landscape Ecology Branch of the U.S. Environmental Protection Agency and the U.S. Department of Agriculture, Agricultural Research Service (Tucson, AZ). Since 1995, U.S. Environmental Protection Agency (EP A) and U...

  17. San Jose, Costa Rica

    NASA Technical Reports Server (NTRS)

    2007-01-01

    San Jose, capital city of Costa Rica, fills the valley between two steep mountain ranges. In this image made from data collected by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument on NASA's Terra satellite, visible, shortwave, and near-infrared wavelengths of light that the sensor observed have been combined to produce a false-color version of the scene in which vegetation is red, urban areas are silvery gray, water is dark blue, and clouds are white. The image was captured on February 8, 2007. San Jose is in the center of the image. The Rio Torres winds through downtown San Jose. Cartago, the much smaller colonial capital, sits in the lower right corner, while the city of Alajuela appears across the river, northwest of San Jose. The cities' manmade surfaces contrast sharply with the lushly vegetated landscape surrounding the city. Greenhouses are common in the region, and their glass roofs may be the brilliant white spots around the outer edges the cities. The long, straight runway of the Tobias Bolanos International Airport is visible as a dark line southeast of Alajuela. The landscape around the two cities shown here is rugged. Steep mountain peaks cast dark shadows across their leeward slopes. Patches of dark red vegetation on the mountains north of San Jose may be rainforest. Coffee plantations also cover the slopes of the mountains around the city. February is the dry season in Costa Rica. During the rainy season, from about April to November, clouds usually block the satellite's view of this tropical location. NASA image created by Jesse Allen, using data provided courtesy of Asaf Ullah and Tim Gubbels, SERVIR project.

  18. Geological literature on the San Joaquin Valley of California

    USGS Publications Warehouse

    Maher, J.C.; Trollman, W.M.; Denman, J.M.

    1973-01-01

    The following list of references includes most of the geological literature on the San Joaquin Valley and vicinity in central California (see figure 1) published prior to January 1, 1973. The San Joaquin Valley comprises all or parts of 11 counties -- Alameda, Calaveras, Contra Costa, Fresno, Kern, Kings, Madera, Merced, San Joaquin, Stanislaus, and Tulare (figure 2). As a matter of convenient geographical classification the boundaries of the report area have been drawn along county lines, and to include San Benito and Santa Clara Counties on the west and Mariposa and Tuolumne Counties on the east. Therefore, this list of geological literature includes some publications on the Diablo and Temblor Ranges on the west, the Tehachapi Mountains and Mojave Desert on the south, and the Sierra Nevada Foothills and Mountains on the east.

  19. 410. Delineator Unknown Revised November 2, 1933 SAN FRANCISCO ANCHORAGE; ...

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

    410. Delineator Unknown Revised November 2, 1933 SAN FRANCISCO ANCHORAGE; SAN FRANCISCO - OAKLAND BAY BRIDGE; "A" - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  20. 75 FR 55975 - Safety Zone; San Diego Harbor Shark Fest Swim; San Diego Bay, San Diego, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-15

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; San Diego Harbor Shark Fest Swim; San Diego... Shark Fest Swim, consisting of 600 swimmers swimming a predetermined course. The sponsor will provide 26...; San Diego Harbor Shark Fest Swim; San Diego Bay, San Diego, CA. (a) Location. The following area is...

  1. BACTERIOPLANKTON DYNAMICS IN NORTHERN SAN FRANCISCO BAY: ROLE OF PARTICLE ASSOCIATION AND SEASONAL FRESHWATER FLOW

    EPA Science Inventory

    Bacterioplankton abundance and metabolic characteristics were observed in northern San Francisco Bay, California, during spring and summer 1996 at three sites: Central Bay, Suisun Bay, and the Sacramento River. These sites spanned a salinity gradient from marine to freshwater, an...

  2. 77 FR 34988 - Notice of Inventory Completion: San Diego State University, San Diego, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-12

    ... National Park Service Notice of Inventory Completion: San Diego State University, San Diego, CA AGENCY: National Park Service, Interior. ACTION: Notice. SUMMARY: San Diego State University Archeology Collections... associated funerary objects may contact San Diego State University Archeology Collections Management...

  3. Structure and mechanics of the San Andreas-San Gregorio fault junction, San Francisco, California

    NASA Astrophysics Data System (ADS)

    Parsons, Tom; Bruns, Terry R.; Sliter, Ray

    2005-01-01

    The right-lateral San Gregorio and San Andreas faults meet west of the Golden Gate near San Francisco. Coincident seismic reflection and refraction profiling across the San Gregorio and San Andreas faults south of their junction shows the crust between them to have formed shallow extensional basins that are dissected by parallel strike-slip faults. We employ a regional finite element model to investigate the long-term consequences of the fault geometry. Over the course of 2-3 m.y. of slip on the San Andreas-San Gregorio fault system, elongated extensional basins are predicted to form between the two faults. An additional consequence of the fault geometry is that the San Andreas fault is expected to have migrated eastward relative to the San Gregorio fault. We thus propose a model of eastward stepping right-lateral fault formation to explain the observed multiple fault strands and depositional basins. The current manifestation of this process might be the observed transfer of slip from the San Andreas fault east to the Golden Gate fault.

  4. 75 FR 53332 - San Carlos Irrigation Project, Arizona

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-31

    ... additional avenues for water conservation. The proposed action includes the reconstruction and lining of... SCIDD and the Central Arizona Water Conservation District to allow delivery of CAP water to... of San Carlos Irrigation Project (SCIP) water delivery facilities near the communities of Casa...

  5. Photocopy of drawing located at National Archives, San Bruno, California ...

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

    Photocopy of drawing located at National Archives, San Bruno, California (Navy # 121-A-37). Minsy building 121 fallout shelter area generator floor plan; N.D. - Mare Island Naval Shipyard, Central Power Plant, California Avenue, norhtwest corner of California Avenue & Seventh Street, Vallejo, Solano County, CA

  6. High-resolution marine seismic reflection data from the San Francisco Bay area

    USGS Publications Warehouse

    Childs, Jonathan R.; Hart, Patrick; Bruns, Terry R.; Marlow, Michael S.; Sliter, Ray

    2000-01-01

    Between 1993 and 1997, the U.S. Geological Survey acquired high-resolution, marine seismic-reflection profile data across submerged portions of known and inferred upper crustal fault zones throughout the greater San Francisco Bay area. Surveys were conducted oversouth San Francisco Bay in the vicinity of the San Bruno shoal (roughly between the San Francisco and Oakland airports), over the offshore extension of the San Andreas fault system west of the Golden Gate, over the Hayward fault to Rodgers Creek fault step-over in San Pablo Bay, and over the Kirby Hills fault where it crosses the western Sacramento Delta. Reconnaissance profiles were acquired elsewhere throughout the San Francisco and San Pablo Bays. These data were acquired by the U.S. Geological Survey, Western Coastal and Marine Geology Team, under the auspices of the Central California/San Francisco Bay Earthquake Hazards Project. Analysis and interpretation of some of these profiles has been published by Marlow and others (1996, 1999). Further analysis and interpretation of these data are available in a USGS. Professional Paper Crustal Structure of the Coastal and Marine San Francisco Bay Region, T. Parsons, editor, http://geopubs.wr.usgs.gov/prof-paper/pp1658/ [link added 2012 mfd].

  7. SAN PEDRO PARKS WILDERNESS, NEW MEXICO.

    USGS Publications Warehouse

    Santos, Elmer S.; Weisner, Robert C.

    1984-01-01

    The San Pedro Parks Wilderness occupies 62. 7 sq mi of the Santa Fe National Forest in north-central New Mexico. Several copper mines, many copper prospects, and a few uranium prospects occur in sedimentary units in the vicinity of the wilderness. These units, where they extend into the wilderness, constitute only a small volume of rock and, judging from analyses of samples and from field observations, are devoid of copper and uranium concentration. Prospects on several of about 65 mining claims within the wilderness revealed concentrations of manganese or barite but only in volumes too small to be considered a demonstrated resource.

  8. Thermal-maturity trends within Franciscan rocks near Big Sur, California: Implications for offset along the San Gregorio San Simeon Hosgri fault zone

    NASA Astrophysics Data System (ADS)

    Underwood, Michael B.; Laughland, Matthew M.; Shelton, Kevin L.; Sedlock, Richard L.

    1995-09-01

    Conventional neotectonic interpretations place the Lucia and Point Sur subterranes of the Franciscan subduction complex on opposite sides of the San Gregorio San Simeon Hosgri dextral fault system and connect that system through the Sur fault zone. Our reconstructed paleotemperature contours, however, are not offset across the San Simeon segment, so differential displacement between the subterranes after peak heating appears to have been negligible. One explanation is that dextral slip on the faults has totaled only 5 10 km. A second possibility is that a discrete Hosgri San Simeon segment extends offshore of the amalgamated Point Sur and Lucia subterranes and that an en echelon stepover transfers dextral slip eastward to the San Gregorio Palo Colorado segment. In either case, the Sur fault zone appears to play a relatively insignificant role in the late Cenozoic tectonic evolution of central California.

  9. San Diego's Capital Planning Process

    ERIC Educational Resources Information Center

    Lytton, Michael

    2009-01-01

    This article describes San Diego's capital planning process. As part of its capital planning process, the San Diego Unified School District has developed a systematic analysis of functional quality at each of its school sites. The advantage of this approach is that it seeks to develop and apply quantifiable metrics and standards for the more…

  10. Sources of groundwater based on Helium analyses in and near the freshwater/saline-water transition zone of the San Antonio segment of the Edwards Aquifer, South-Central Texas, 2002-03

    USGS Publications Warehouse

    Hunt, Andrew G.; Lambert, Rebecca B.; Fahlquist, Lynne

    2010-01-01

    This report evaluates dissolved noble gas data, specifically helium-3 and helium-4, collected by the U.S. Geological Survey, in cooperation with the San Antonio Water System, during 2002-03. Helium analyses are used to provide insight into the sources of groundwater in the freshwater/saline-water transition zone of the San Antonio segment of the Edwards aquifer. Sixty-nine dissolved gas samples were collected from 19 monitoring wells (categorized as fresh, transitional, or saline on the basis of dissolved solids concentration in samples from the wells or from fluid-profile logging of the boreholes) arranged in five transects, with one exception, across the freshwater/saline-water interface (the 1,000-milligrams-per-liter dissolved solids concentration threshold) of the Edwards aquifer. The concentration of helium-4 (the dominant isotope in atmospheric and terrigenic helium) in samples ranged from 63 microcubic centimeters per kilogram at standard temperature (20 degrees Celsius) and pressure (1 atmosphere) in a well in the East Uvalde transect to 160,587 microcubic centimeters per kilogram at standard temperature and pressure in a well in the Kyle transect. Helium-4 concentrations in the 10 saline wells generally increase from the western transects to the eastern transects. Increasing helium-4 concentrations from southwest to northeast in the transition zone, indicating increasing residence time of groundwater from southwest to northeast, is consistent with the longstanding conceptualization of the Edwards aquifer in which water recharges in the southwest, flows generally northeasterly (including in the transition zone, although more slowly than in the fresh-water zone), and discharges at major springs in the northeast. Excess helium-4 was greater than 1,000 percent for 60 of the 69 samples, indicating that terrigenic helium is largely present and that most of the excess helium-4 comes from sources other than the atmosphere. The helium data of this report cannot be

  11. Perspective View, San Andreas Fault

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The prominent linear feature straight down the center of this perspective view is California's famous San Andreas Fault. The image, created with data from NASA's Shuttle Radar Topography Mission (SRTM), will be used by geologists studying fault dynamics and landforms resulting from active tectonics. This segment of the fault lies west of the city of Palmdale, Calif., about 100 kilometers (about 60 miles) northwest of Los Angeles. The fault is the active tectonic boundary between the North American plate on the right, and the Pacific plate on the left. Relative to each other, the Pacific plate is moving away from the viewer and the North American plate is moving toward the viewer along what geologists call a right lateral strike-slip fault. Two large mountain ranges are visible, the San Gabriel Mountains on the left and the Tehachapi Mountains in the upper right. Another fault, the Garlock Fault lies at the base of the Tehachapis; the San Andreas and the Garlock Faults meet in the center distance near the town of Gorman. In the distance, over the Tehachapi Mountains is California's Central Valley. Along the foothills in the right hand part of the image is the Antelope Valley, including the Antelope Valley California Poppy Reserve. The data used to create this image were acquired by SRTM aboard the Space Shuttle Endeavour, launched on February 11, 2000.

    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.

    SRTM uses 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

  12. 78 FR 58878 - Safety Zone; San Diego Shark Fest Swim; San Diego Bay, San Diego, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-25

    ... Acronyms DHS Department of Homeland Security FR Federal Register NPRM Notice of Proposed Rulemaking A... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; San Diego Shark Fest Swim; San Diego Bay... Diego Shark Fest Swim. This safety zone is necessary to provide for the safety of the participants,...

  13. 78 FR 34895 - Safety Zone; San Francisco Independence Day Fireworks Display, San Francisco Bay, San Francisco, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-11

    ... SECURITY Coast Guard 33 CFR Part 165 Safety Zone; San Francisco Independence Day Fireworks Display, San Francisco Bay, San Francisco, CA AGENCY: Coast Guard, DHS. ACTION: Notice of enforcement of regulation. SUMMARY: The Coast Guard will enforce the safety zones for the San Francisco Independence Day...

  14. Central California Action Associates, Inc.

    ERIC Educational Resources Information Center

    Sortor, Maia, Comp.

    The overall goal of the Central California Action Associates Inc. (CCAA) program is to provide basic education and pre-vocational training so that migrant and seasonal adult farm workers will be able to upgrade their economic and social lives. Without increased educational attainment, the San Joaquin Valley farm workers face a grim future because…

  15. Geologic Map of the San Luis Quadrangle, Costilla County, Colorado

    USGS Publications Warehouse

    Machette, Michael N.; Thompson, Ren A.; Drenth, Benjamin J.

    2008-01-01

    The map area includes San Luis and the primarily rural surrounding area. San Luis, the county seat of Costilla County, is the oldest surviving settlement in Colorado (1851). West of the town are San Pedro and San Luis mesas (basalt-covered tablelands), which are horsts with the San Luis fault zone to the east and the southern Sangre de Cristo fault zone to the west. The map also includes the Sanchez graben (part of the larger Culebra graben), a deep structural basin that lies between the San Luis fault zone (on the west) and the central Sangre de Cristo fault zone (on the east). The oldest rocks exposed in the map area are the Pliocene to upper Oligocene basin-fill sediments of the Santa Fe Group, and Pliocene Servilleta Basalt, a regional series of 3.7?4.8 Ma old flood basalts. Landslide deposits and colluvium that rest on sediments of the Santa Fe Group cover the steep margins of the mesas. Rare exposures of the sediment are comprised of siltstones, sandstones, and minor fluvial conglomerates. Most of the low ground surrounding the mesas and in the graben is covered by surficial deposits of Quaternary age. The alluvial deposits are subdivided into three Pleistocene-age units and three Holocene-age units. The oldest Pleistocene gravel (unit Qao) forms extensive coalesced alluvial fan and piedmont surfaces, the largest of which is known as the Costilla Plain. This surface extends west from San Pedro Mesa to the Rio Grande. The primary geologic hazards in the map area are from earthquakes, landslides, and localized flooding. There are three major fault zones in the area (as discussed above), and they all show evidence for late Pleistocene to possible Holocene movement. The landslides may have seismogenic origins; that is, they may be stimulated by strong ground shaking during large earthquakes. Machette and Thompson based this geologic map entirely on new mapping, whereas Drenth supplied geophysical data and interpretations.

  16. 78 FR 20792 - Safety Zone; San Francisco Giants Fireworks Display, San Francisco, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-08

    ... SECURITY Coast Guard 33 CFR Part 165 Safety Zone; San Francisco Giants Fireworks Display, San Francisco, CA... enforce the safety zone for the San Francisco Giants Fireworks Display in the Captain of the Port, San... Grade William Hawn, U.S. Coast Guard Sector San Francisco; telephone (415) 399-7442 or email at...

  17. 77 FR 15260 - Safety Zone; San Francisco Fireworks Display, San Francisco, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-15

    ... SECURITY Coast Guard 33 CFR Part 165 Safety Zone; San Francisco Fireworks Display, San Francisco, CA AGENCY... safety zone for the San Francisco Giants Fireworks Display in the Captain of the Port, San Francisco area... Sector San Francisco; telephone (415) 399-7442 or email at D11-PF-MarineEvents@uscg.mil ....

  18. 76 FR 14051 - Notice of Inventory Completion: San Francisco State University, San Francisco, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-15

    ... National Park Service Notice of Inventory Completion: San Francisco State University, San Francisco, CA... inventory of human remains in the control of San Francisco State University, San Francisco, CA. The human.... A detailed assessment of the human remains was made by San Francisco State University...

  19. 33 CFR 165.754 - Safety Zone: San Juan Harbor, San Juan, PR.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Safety Zone: San Juan Harbor, San... Zone: San Juan Harbor, San Juan, PR. (a) Regulated area. A moving safety zone is established in the following area: (1) The waters around Liquefied Petroleum Gas ships entering San Juan Harbor in an area...

  20. 33 CFR 165.754 - Safety Zone: San Juan Harbor, San Juan, PR.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Safety Zone: San Juan Harbor, San... Zone: San Juan Harbor, San Juan, PR. (a) Regulated area. A moving safety zone is established in the following area: (1) The waters around Liquefied Petroleum Gas ships entering San Juan Harbor in an area...

  1. 76 FR 55796 - Safety Zone; TriRock Triathlon, San Diego Bay, San Diego, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-09

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; TriRock Triathlon, San Diego Bay, San Diego... safety zone upon the specified navigable waters of the San Diego Bay, San Diego, California, in support of a bay swim in San Diego Harbor. This safety zone is necessary to provide for the safety of...

  2. 75 FR 38412 - Safety Zone; San Diego POPS Fireworks, San Diego, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-02

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; San Diego POPS Fireworks, San Diego, CA... zone on the ] navigable waters of San Diego Bay in support of the San Diego POPS Fireworks. This safety.... Coast Guard Sector San Diego, CA; telephone 619-278- 7262, e-mail Shane.E.Jackson@uscg.mil . If you...

  3. 77 FR 28771 - Safety Zone; San Francisco Giants Fireworks Display, San Francisco, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-16

    ... SECURITY Coast Guard 33 CFR Part 165 Safety Zone; San Francisco Giants Fireworks Display, San Francisco, CA... enforce the safety zone for the San Francisco Giants Fireworks Display in the Captain of the Port, San... Sector San Francisco; telephone (415) 399-7442 or email at D11-PF-MarineEvents@uscg.mil ....

  4. 41. Historic American Buildings Survey San Francisco CallBulletin Library San ...

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

    41. Historic American Buildings Survey San Francisco Call-Bulletin Library San Francisco, California INTERIOR VIEW OF CHURCH BEFORE RESTORATION - 1934 - Mission San Carlos Borromeo, Rio Road & Lausen Drive, Carmel-by-the-Sea, Monterey County, CA

  5. Interior, view of central hall staircase showing bracketed stair, square ...

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

    Interior, view of central hall staircase showing bracketed stair, square balusters and fluted newel post, camera facing southwest - Naval Training Station, Senior Officers' Quarters District, Quarters No. 4, Naval Station Treasure Island, 4 Whiting Way, Yerba Buena Island, San Francisco, San Francisco County, CA

  6. DISTRIBUTION AND COMPOSITION OF DISSOLVED AND PARTICULATE ORGANIC CARBON IN NORTHERN SAN FRANCISCO BAY DURING LOW FRESHWATER FLOW CONDITIONS

    EPA Science Inventory

    The distribution of organic matter was studied in northern San Francisco Bay monthly through spring and summer 1996 along the salinity gradient from the Sacramento River to Central Bay. Dissolved constituents included monosaccharides (MONO), total carbohydrates (TCHO), dissolved ...

  7. Quaternary geology of Alameda County, and parts of Contra Costa, Santa Clara, San Mateo, San Francisco, Stanislaus, and San Joaquin counties, California: a digital database

    USGS Publications Warehouse

    Helley, E.J.; Graymer, R.W.

    1997-01-01

    Alameda County is located at the northern end of the Diablo Range of Central California. It is bounded on the north by the south flank of Mount Diablo, one of the highest peaks in the Bay Area, reaching an elevation of 1173 meters (3,849 ft). San Francisco Bay forms the western boundary, the San Joaquin Valley borders it on the east and an arbitrary line from the Bay into the Diablo Range forms the southern boundary. Alameda is one of the nine Bay Area counties tributary to San Francisco Bay. Most of the country is mountainous with steep rugged topography. Alameda County is covered by twenty-eight 7.5' topographic Quadrangles which are shown on the index map. The Quaternary deposits in Alameda County comprise three distinct depositional environments. One, forming a transgressive sequence of alluvial fan and fan-delta facies, is mapped in the western one-third of the county. The second, forming only alluvial fan facies, is mapped in the Livermore Valley and San Joaquin Valley in the eastern part of the county. The third, forming a combination of Eolian dune and estuarine facies, is restricted to the Alameda Island area in the northwestern corner of the county.

  8. Cerro de Vidrio rhyolitic dome: evidence for Late Pliocene volcanism in the central Andean flat-slab region, Lama-Veladero district, 29°20'S, San Juan Province, Argentina

    NASA Astrophysics Data System (ADS)

    Bissig, Thomas; Clark, Alan H.; Lee, James K. W.

    2002-10-01

    Magmatic activity in the El Indio-Pascua Au-Ag-Cu belt, situated in the Cordillera Principal at latitudes 29-30°S at the center of the southern Central Andean flat subduction regime, did not, as previously assumed, cease at 5-6 Ma but continued locally until the Late Pliocene. New and essentially identical 40Ar- 39Ar laser step-heating ages of 2.1±0.5 Ma (biotite) and 2.0±0.2 Ma (glass) are recorded for a rhyolitic dome, the Cerro de Vidrio, in the northern Valle del Cura region near the Veladero Au (-Ag) property. The rhyolite is geochemically distinct from local Upper Miocene volcanic rocks; it is slightly but unequivocally peraluminous and does not exhibit significant REE fractionation apart from a pronounced negative Eu anomaly, a feature also shown by the Upper Paleozoic-Lower Mesozoic basement units of the area. This suggests that magma generation occurred in a garnet-free environment, which implies anatexis at shallower levels than for the rhyolites of the Upper Miocene Vallecito Formation.

  9. Environmental setting of the San Joaquin-Tulare basins, California

    USGS Publications Warehouse

    Gronberg, JoAnn A.; Dubrovsky, Neil M.; Kratzer, Charles R.; Domagalski, Joseph L.; Brown, Larry R.; Burow, Karen R.

    1998-01-01

    The National Water-Quality Assessment Program for the San Joaquin- Tulare Basins began in 1991 to study the effects of natural and anthropogenic influences on the quality of ground water, surface water, biology, and ecology. The San Joaquin-Tulare Basins study unit, which covers approximately 31,200 square miles in central California, is made up of the San Joaquin Valley, the eastern slope of the Coast Ranges to the west, and the western slope of the Sierra Nevada to the east. The sediments of the San Joaquin Valley can be divided into alluvial fans and basin deposits. The San Joaquin River receives water from tributaries draining the Sierra Nevada and Coast Ranges, and except for streams discharging directly to the Sacramento-San Joaquin Delta, is the only surface- water outlet from the study unit. The surface-water hydrology of the San Joaquin-Tulare Basins study unit has been significantly modified by development of water resources. Almost every major river entering the valley from the Sierra Nevada has one or more reservoirs. Almost every tributary and drainage into the San Joaquin River has been altered by a network of canals, drains, and wasteways. The Sierra Nevada is predominantly forested, and the Coast Ranges and the foothills of the Sierra Nevada are predominately rangeland. The San Joaquin Valley is dominated by agriculture, which utilized approximately 14.7 million acre-feet of water and 597 million pounds active ingredient of nitrogen and phosphorus fertilizers in 1990, and 88 million pounds active ingredient of pesticides in 1991. In addition, the livestock industry contributed 318 million pounds active ingredient of nitrogen and phosphorus from manure in 1987. This report provides the background information to assess the influence of these and other factors on water quality and to provide the foundation for the design and interpretation of all spatial data. These characterizations provide a basis for comparing the influences of human activities

  10. Sand waves at the mouth of San Francisco Bay, California

    USGS Publications Warehouse

    Gibbons, Helen; Barnard, Patrick L.

    2007-01-01

    The U.S. Geological Survey; California State University, Monterey Bay; U.S. Army Corps of Engineers; National Oceanic and Atmospheric Administration; and Center for Integrative Coastal Observation, Research and Education partnered to map central San Francisco Bay and its entrance under the Golden Gate Bridge using multibeam echosounders. View eastward, through the Golden Gate into central San Francisco Bay. Depth of sea floor color coded: red (less than 10 m deep) to purple (more than 100 m deep). Land from USGS digital orthophotographs (DOQs) overlaid on USGS digital elevation models (DEMs). Sand waves in this view average 6 m in height and 80 m from crest to crest. Golden Gate Bridge is about 2 km long. Vertical exaggeration is approximately 4x for sea floor, 2x for land.

  11. Perspective View, San Andreas Fault

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The prominent linear feature straight down the center of this perspective view is the San Andreas Fault in an image created with data from NASA's shuttle Radar Topography Mission (SRTM), which will be used by geologists studying fault dynamics and landforms resulting from active tectonics. This segment of the fault lies west of the city of Palmdale, California, about 100 kilometers (about 60 miles) northwest of Los Angeles. The fault is the active tectonic boundary between the North American plate on the right, and the Pacific plate on the left. Relative to each other, the Pacific plate is moving away from the viewer and the North American plate is moving toward the viewer along what geologists call a right lateral strike-slip fault. This area is at the junction of two large mountain ranges, the San Gabriel Mountains on the left and the Tehachapi Mountains on the right. Quail Lake Reservoir sits in the topographic depression created by past movement along the fault. Interstate 5 is the prominent linear feature starting at the left edge of the image and continuing into the fault zone, passing eventually over Tejon Pass into the Central Valley, visible at the upper left.

    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

  12. Dennis Hill, Photographer April 1998 VIEW OF FRONT OF SAN ...

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

    Dennis Hill, Photographer April 1998 VIEW OF FRONT OF SAN FRANCISCO - OAKLAND BAY BRIDGE FIREHOUSE, FACING SOUTHWEST - San Francisco Oakland Bay Bridge Firehouse, Adjacent to north side of bridge on Yerba Buena Island, San Francisco, San Francisco County, CA

  13. 22. Photocopy of photograph (from San Francisco Chronicle Collection) Photographer ...

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

    22. Photocopy of photograph (from San Francisco Chronicle Collection) Photographer unknown, Date unknown SIDE VIEW OF CHURCH - Mission San Miguel Arcangel, Highway 101, San Miguel, San Luis Obispo County, CA

  14. 1. VIEW LOOKING SOUTHWEST AT TURNOUT ON SAN TAN FLOODWATER ...

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

    1. VIEW LOOKING SOUTHWEST AT TURNOUT ON SAN TAN FLOOD-WATER CANAL TO SAN TAN INDIAN CANAL - San Carlos Irrigation Project, San Tan Flood Water Canal, North Side of Gila River, Coolidge, Pinal County, AZ

  15. Mantle fluids in the San Andreas fault system, California

    USGS Publications Warehouse

    Kennedy, B.M.; Kharaka, Y.K.; Evans, William C.; Ellwood, A.; DePaolo, D.J.; Thordsen, J.; Ambats, G.; Mariner, R.H.

    1997-01-01

    Fluids associated with the San Andreas and companion faults n central and south-central California have high 3He/4He ratios. The lack of correlation between helium isotopes and fluid chemistry or local geology requires that fluids enter the fault system from the mantle. Mantle fluids passing through the ductile lower crust must enter the brittle fault zone at or near lithostatic pressures; estimates of fluid flux based on helium isotopes suggest that they may thus contribute directly to fault-weakening high-fluid pressures at seismogenic depths.

  16. California State Waters Map Series: offshore of San Francisco, California

    USGS Publications Warehouse

    Cochrane, Guy R.; Johnson, Samuel Y.; Dartnell, Peter; Greene, H. Gary; Erdey, Mercedes D.; Golden, Nadine E.; Hartwell, Stephen R.; Endris, Charles A.; Manson, Michael W.; Sliter, Ray W.; Kvitek, Rikk G.; Watt, Janet Tilden; Ross, Stephanie L.; Bruns, Terry R.; Cochrane, Guy R.; Cochran, Susan A.

    2015-01-01

    Circulation over the continental shelf in the Offshore of San Francisco map area is dominated by the southward-flowing California Current, an eastern limb of the North Pacific Gyre that flows from Oregon to Baja California. At its midpoint offshore of central California, the California Current transports subarctic surface waters southeastward, about 150 to 1,300 km from shore. Seasonal northwesterly winds that are, in part, responsible for the California Current, generate coastal upwelling. Ocean temperatures offshore of central California have increased over the past 50 years, driving an ecosystem shift from the productive subarctic regime towards a depopulated subtropical environment.

  17. San Language Development for Education in South Africa: The South African San Institute and the San Language Committees

    ERIC Educational Resources Information Center

    Pamo, Billies

    2011-01-01

    This article focuses on the 3 San communities in South Africa: the !Xun, the Khwe, and the [image omitted]Khomani San. The !Xun and Khwe communities are living in Platfontein, near Kimberley in the Northern Cape. The [image omitted]Khomani San community is living in Upington and in the southern Kalahari, which are also in the Northern Cape. This…

  18. Resistance Management for San Jose Scale (Hemiptera: Diaspididae).

    PubMed

    Buzzetti, K; Chorbadjian, R A; Nauen, R

    2015-12-01

    The San Jose scale Diaspidiotus perniciosus Comstock is one of the most important pests of deciduous fruit trees. The major cause of recent outbreaks in apple orchards is thought to be the development of insecticide resistance, specifically organophosphates. The first report was given in North America, and now, in Chile. In the present study, San Jose scale populations collected from two central regions of Chile were checked for their susceptibility to different mode of action insecticides in order to establish alternatives to manage this pest. No evidence of cross resistance between organophosphates insecticides and acetamiprid, buprofezin, pyriproxyfen, spirotetramat, sulfoxaflor, or thiacloprid was found. Baselines of LC50-LC95 for different life stages of San Jose scale are given, as reference to future studies of resistance monitoring. The systemic activity of acetamiprid, spirotetramat, and thiacloprid was higher than the contact residue effect of these compounds. For sulfoxaflor, both values were similar. Program treatments including one or more of these compounds are compared in efficacy and impact on resistance ratio values. In order to preserve new insecticides as an important tool to control San Jose scale, resistance management programs should be implemented, considering insecticide mode of action classes alternated or mixed.

  19. Resistance Management for San Jose Scale (Hemiptera: Diaspididae).

    PubMed

    Buzzetti, K; Chorbadjian, R A; Nauen, R

    2015-12-01

    The San Jose scale Diaspidiotus perniciosus Comstock is one of the most important pests of deciduous fruit trees. The major cause of recent outbreaks in apple orchards is thought to be the development of insecticide resistance, specifically organophosphates. The first report was given in North America, and now, in Chile. In the present study, San Jose scale populations collected from two central regions of Chile were checked for their susceptibility to different mode of action insecticides in order to establish alternatives to manage this pest. No evidence of cross resistance between organophosphates insecticides and acetamiprid, buprofezin, pyriproxyfen, spirotetramat, sulfoxaflor, or thiacloprid was found. Baselines of LC50-LC95 for different life stages of San Jose scale are given, as reference to future studies of resistance monitoring. The systemic activity of acetamiprid, spirotetramat, and thiacloprid was higher than the contact residue effect of these compounds. For sulfoxaflor, both values were similar. Program treatments including one or more of these compounds are compared in efficacy and impact on resistance ratio values. In order to preserve new insecticides as an important tool to control San Jose scale, resistance management programs should be implemented, considering insecticide mode of action classes alternated or mixed. PMID:26470382

  20. South San Francisco Bay, California

    USGS Publications Warehouse

    Dartnell, Peter; Gibbons, Helen

    2007-01-01

    View eastward. Elevations in mapped area color coded: purple (approx 15 m below sea level) to red-orange (approx 90 m above sea level). South San Francisco Bay is very shallow, with a mean water depth of 2.7 m (8.9 ft). Trapezoidal depression near San Mateo Bridge is where sediment has been extracted for use in cement production and as bay fill. Land from USGS digital orthophotographs (DOQs) overlaid on USGS digital elevation models (DEMs). Distance across bottom of image approx 11 km (7 mi); vertical exaggeration 1.5X.

  1. Update: San Andreas Fault experiment

    NASA Technical Reports Server (NTRS)

    Christodoulidis, D. C.; Smith, D. E.

    1984-01-01

    Satellite laser ranging techniques are used to monitor the broad motion of the tectonic plates comprising the San Andreas Fault System. The San Andreas Fault Experiment, (SAFE), has progressed through the upgrades made to laser system hardware and an improvement in the modeling capabilities of the spaceborne laser targets. Of special note is the launch of the Laser Geodynamic Satellite, LAGEOS spacecraft, NASA's only completely dedicated laser satellite in 1976. The results of plate motion projected into this 896 km measured line over the past eleven years are summarized and intercompared.

  2. 75 FR 39166 - Safety Zone; San Francisco Giants Baseball Game Promotion, San Francisco, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-08

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; San Francisco Giants Baseball Game... Bay off San Francisco, CA in support of the San Francisco Giants Baseball Game Promotion. This safety... Giants will sponsor the San Francisco Giants Baseball Game Promotion on July 16, 2010, on the...

  3. 75 FR 77756 - Safety Zone; San Diego Parade of Lights Fireworks, San Diego, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-14

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; San Diego Parade of Lights Fireworks, San... San Diego Parade of Lights Fireworks Displays on December 12 and December 19, 2010. This safety zone... San Diego Parade of Lights Fireworks Displays, which will include two fireworks...

  4. 78 FR 18238 - Safety Zone; SFPD Training Safety Zone; San Francisco Bay, San Francisco, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-26

    ... of Homeland Security FR Federal Register SFPD San Francisco Police Department NPRM Notice of Proposed... Hunters Point in San Francisco, CA in support of the San Francisco Police Department's maritime....C sections 1221 et seq.). San Francisco Police Department will host the SFPD Training Safety Zone...

  5. 77 FR 46115 - Notice of Inventory Completion: San Diego Museum of Man, San Diego, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-02

    ... National Park Service Notice of Inventory Completion: San Diego Museum of Man, San Diego, CA AGENCY: National Park Service, Interior. ACTION: Notice. SUMMARY: The San Diego Museum of Man has completed an... contact the San Diego Museum of Man. Repatriation of the human remains to the Indian tribe stated...

  6. 76 FR 38305 - Safety Zone; San Francisco Chronicle Fireworks Display, San Francisco, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-30

    ... SECURITY Coast Guard 33 CFR Part 165 Safety Zone; San Francisco Chronicle Fireworks Display, San Francisco... will enforce the safety zones for the annual San Francisco Chronicle Fireworks Display (Independence Day Celebration for the City of San Francisco Fireworks). This action is necessary to control...

  7. 76 FR 45693 - Safety Zone; San Diego POPS Fireworks, San Diego, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-01

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; San Diego POPS Fireworks, San Diego, CA... temporary safety zone on the navigable waters of San Diego Bay in support of the San Diego POPS Fireworks... rule, call or e-mail Petty Officer Shane Jackson, Waterways Management, U.S. Coast Guard Sector...

  8. 77 FR 57494 - Safety Zone; Fleet Week Fireworks, San Francisco Bay, San Francisco, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-18

    ... SECURITY Coast Guard 33 CFR Part 165 Safety Zone; Fleet Week Fireworks, San Francisco Bay, San Francisco... will enforce the safety zone for the Fleet Week Fireworks in the Captain of the Port, San Francisco... William Hawn, U.S. ] Coast Guard Sector San Francisco; telephone (415) 399-7442 or email at...

  9. 77 FR 42647 - Safety Zone: San Diego Symphony POPS Fireworks; San Diego, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-20

    ... FR Federal Register NPRM Notice of Proposed Rulemaking A. Regulatory History and Information The... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone: San Diego Symphony POPS Fireworks; San... establishing a safety zone on the navigable waters of San Diego Bay in support of the San Diego Symphony...

  10. 76 FR 75908 - Notice of Inventory Completion: The University of California, San Diego, San Diego, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-05

    ... National Park Service Notice of Inventory Completion: The University of California, San Diego, San Diego... California on behalf of the University of California, San Diego, have completed an inventory of human remains... contact the University of California, San Diego. Disposition of the human remains and associated...

  11. 76 FR 46352 - Approval of Noise Compatibility Program for San Diego International, San Diego, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-02

    ... Federal Aviation Administration Approval of Noise Compatibility Program for San Diego International, San... Administration (FAA) announces its findings on the noise compatibility program submitted by San Diego Regional... maps submitted by San Diego Regional Airport Authority under Part 150 were in compliance...

  12. 77 FR 37604 - Safety Zone; Fourth of July Fireworks, City of San Francisco, San Francisco, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-22

    ... SECURITY Coast Guard 33 CFR Part 165 Safety Zone; Fourth of July Fireworks, City of San Francisco, San... of the Port, San Francisco area of responsibility during the dates and times noted below. This action... Ensign William Hawn, U.S. Coast Guard Sector San Francisco; ] telephone (415) 399-7442 or email at...

  13. 75 FR 35651 - Safety Zone; San Francisco Chronicle Fireworks Display, San Francisco, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-23

    ... SECURITY Coast Guard 33 CFR Part 165 Safety Zone; San Francisco Chronicle Fireworks Display, San Francisco... will enforce the Independence Day Celebration for the City of San Francisco Fireworks safety zone from... Independence Day Celebration for the City of San Francisco Fireworks safety zone from 11 a.m. through 10...

  14. 77 FR 37603 - Safety Zone; San Francisco Independence Day Fireworks Display, San Francisco, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-22

    ... SECURITY Coast Guard 33 CFR Part 165 Safety Zone; San Francisco Independence Day Fireworks Display, San... Guard will enforce the safety zones for the San Francisco Independence Day Fireworks Display in the Captain of the Port, San Francisco area of responsibility during the dates and times noted below....

  15. 77 FR 59648 - Notice of Inventory Completion: San Francisco State University, NAGPRA Program, San Francisco, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-28

    ... National Park Service Notice of Inventory Completion: San Francisco State University, NAGPRA Program, San Francisco, CA AGENCY: National Park Service, Interior. ACTION: Notice. SUMMARY: The San Francisco State... associated funerary objects may contact the San Francisco State University NAGPRA Program. Repatriation...

  16. 408. Delineator Unknown September 19, 1933 SAN FRANCISCO OAKLAND ...

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

    408. Delineator Unknown September 19, 1933 SAN FRANCISCO - OAKLAND BAY BRIDGE; STUDY FOR SAN FRANCISCO ANCHORAGE; TIMOTHY L. PFLUEGER, ARTHUR BROWN JR., JOHN J. DONOVAN; BOARD OF CONSULTING ARCHITECTS; SHEET NO. 26 - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  17. 407. Delineator Unknown July 11, 1933 PERSPECTIVE STUDY OF SAN ...

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

    407. Delineator Unknown July 11, 1933 PERSPECTIVE STUDY OF SAN FRANCISCO ANCHORAGE; SAN FRANCISCO - OAKLAND BAY BRIDGE; TIMOTHY L. PFLUEGER, ARTHUR BROWN JR., JOHN J. DONOVAN; BOARD OF CONSULTING ARCHITECTS; SHEET 12 - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  18. 406. Delineator Unknown April 19, 1933 ELEVATION STUDY FOR SAN ...

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

    406. Delineator Unknown April 19, 1933 ELEVATION STUDY FOR SAN FRANCISCO ANCHORAGE; SAN FRANCISCO - OAKLAND BAY BRIDGE; BOARD OF CONSULTING ARCHITECTS; TIMOTHY L. PFLUEGER, ARTHUR BROWN JR., JOHN J. DONOVAN; SHEET 23 - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  19. A Spanish Borderlands Community: San Antonio.

    ERIC Educational Resources Information Center

    Teja, Jesus F. de la

    2000-01-01

    Discusses the founding of San Antonio, originally San Antonio de Bexar, which, in 1718, came into being as a military settlement involved in Spanish imperial defensive measures. Focuses on the development and continued growth of San Antonio, Texas's most populous city in the 19th century. (CMK)

  20. 27 CFR 9.171 - San Bernabe.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false San Bernabe. 9.171 Section... THE TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.171 San Bernabe. (a) Name. The name of the viticultural area described in this section is “San Bernabe”....

  1. 27 CFR 9.110 - San Benito.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false San Benito. 9.110 Section... THE TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.110 San Benito. (a) Name. The name of the viticultural area described in this section is “San Benito.”...

  2. 27 CFR 9.110 - San Benito.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false San Benito. 9.110 Section... THE TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.110 San Benito. (a) Name. The name of the viticultural area described in this section is “San Benito.”...

  3. 27 CFR 9.56 - San Lucas.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false San Lucas. 9.56 Section 9... TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.56 San Lucas. (a) Name. The name of the viticultural area described in this section is “San Lucas.” (b) Approved...

  4. 27 CFR 9.56 - San Lucas.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false San Lucas. 9.56 Section 9... TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.56 San Lucas. (a) Name. The name of the viticultural area described in this section is “San Lucas.” (b) Approved...

  5. 27 CFR 9.171 - San Bernabe.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false San Bernabe. 9.171 Section... THE TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.171 San Bernabe. (a) Name. The name of the viticultural area described in this section is “San Bernabe”....

  6. San Francisco Bay Sand Mining Resource Evaluation and Impact Analysis

    NASA Astrophysics Data System (ADS)

    Fenical, S.; Tirindelli, M.; Sicular, D.; Gragg, J.; Huitt, C.

    2012-12-01

    This paper presents results of the evaluation of potential future sand resources within certain Central San Francisco Bay (Central Bay) sand mining lease areas, as well as the potential impacts of further mining these areas for a ten-year period. The study consisted of morphological analysis using field measurements and hydrodynamic modeling, and covered a wide spectrum of physical processes including tidal and river circulation, salinity, sediment transport, and morphology. The study was conducted within the framework of an Environmental Impact Report (EIR) prepared by the California State Lands Commission (CSLC) as part of the discretionary approval process for issuing new mining leases. The results of the morphological analysis indicate a measurable depletion of sand resources in the Central Bay lease areas during the period 1997-2008, and that for the purposes of the proposed ten-year mining lease renewal, sand mining resources in Central Bay are largely limited to material already in place. The morphological analysis results also indicate that the proposed additional ten years of sand mining in the Central Bay lease areas are not likely to cause a significant impact on sediment transport and budgets in areas outside the vicinity of the lease areas, such as the San Francisco Bar, Ocean Beach, etc. Numerical modeling results, including particle tracking exercises, do indicate a net seaward transport of sand, and that a linkage exists between the mining areas and offshore areas (San Francisco Bar, Ocean Beach, etc). However, the modeling results demonstrate that the linkage is weak, and that any measurable changes in hydrodynamics, salinity and sediment transport/morphology caused by the mining activities are likely to be confined to the vicinity of the mining areas.

  7. 33 CFR 165.1185 - Regulated Navigation Area; San Francisco Bay, San Pablo Bay, Carquinez Strait, Suisun Bay...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Francisco Bay, San Pablo Bay, Carquinez Strait, Suisun Bay, Sacramento River, San Joaquin River, and..., Sacramento River, San Joaquin River, and connecting waters in California. (a) Location. All waters of San Francisco Bay, San Pablo Bay, Carquinez Strait, Suisun Bay, Sacramento River, San Joaquin River,...

  8. Seeking Justice in San Francisco

    ERIC Educational Resources Information Center

    Pascopella, Angela

    2010-01-01

    This article discusses the life of Carlos A. Garcia, superintendent at the San Francisco Unified School District. Garcia was born in Chicago, but his parents shortly thereafter moved back to their homeland of Mexico for a few years. When Garcia was almost 5, his family moved to Los Angeles, where his parents worked in factories and Garcia was…

  9. Building the San Francisco Beacons.

    PubMed

    Eldredge, Sue; Piha, Sam; Levin, Fodi

    2002-01-01

    San Francisco's Beacon Initiative is designed to foster youth development on a large scale. Its intermediary, Community Network for Youth Development, used a theory of change process to forge consensus and create a road map to guide this large collaborative toward its long-term goals.

  10. Danggui-Shaoyao-San: New Hope for Alzheimer's Disease.

    PubMed

    Fu, Xin; Wang, QiuHong; Wang, ZhiBin; Kuang, HaiXue; Jiang, Pinghui

    2016-08-01

    Danggui-Shaoyao-San (DSS), also called Toki-shakuyaku-san (TJ-23) or Dangguijakyak-san (DJS), is a well-known herbal formula (Angelica sinensis (Oliv.) Diels., Ligusticum chuanxiong Hort., Paeonia lactiflora pall., Poria cocos (Schw.) Wolf, Alisma orientalis (Sam.) Juzep., Atractylodes macrocephala Koidz.), which has been widely used in oriental countries for the treatment of various gynecological diseases. Recent studies show that DSS has an effect on free radical-mediated neurological diseases and exhibits anti-inflammatory and antioxidant activities and reduces cell apoptosis in the hippocampus. In addition, DSS mediates the modulation of central monoamine neurotransmitter systems and ameliorates dysfunction of the central cholinergic nervous system and scopolamine-induced decrease in ACh levels. DSS improves the function of the dopaminergic, adrenergic, and serotonergic nervous systems. Interestingly, DSS can alleviate cognitive dysfunction of Alzheimer's disease (AD) patients, suggesting that it is a useful therapeutic agent for AD. This paper reviews the mechanism of DSS for the treatment of AD. PMID:27493835

  11. Danggui-Shaoyao-San: New Hope for Alzheimer's Disease

    PubMed Central

    Fu, Xin; Wang, QiuHong; Wang, ZhiBin; Kuang, HaiXue; Jiang, Pinghui

    2016-01-01

    Danggui-Shaoyao-San (DSS), also called Toki-shakuyaku-san (TJ-23) or Dangguijakyak-san (DJS), is a well-known herbal formula (Angelica sinensis (Oliv.) Diels., Ligusticum chuanxiong Hort., Paeonia lactiflora pall., Poria cocos (Schw.) Wolf, Alisma orientalis (Sam.) Juzep., Atractylodes macrocephala Koidz.), which has been widely used in oriental countries for the treatment of various gynecological diseases. Recent studies show that DSS has an effect on free radical-mediated neurological diseases and exhibits anti-inflammatory and antioxidant activities and reduces cell apoptosis in the hippocampus. In addition, DSS mediates the modulation of central monoamine neurotransmitter systems and ameliorates dysfunction of the central cholinergic nervous system and scopolamine-induced decrease in ACh levels. DSS improves the function of the dopaminergic, adrenergic, and serotonergic nervous systems. Interestingly, DSS can alleviate cognitive dysfunction of Alzheimer's disease (AD) patients, suggesting that it is a useful therapeutic agent for AD. This paper reviews the mechanism of DSS for the treatment of AD. PMID:27493835

  12. ASTER Flyby of San Francisco

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The Advanced Spaceborne Thermal Emission and Reflection radiometer, ASTER, is an international project: the instrument was supplied by Japan's Ministry of International Trade and Industry. A joint US/Japan science team developed algorithms for science data products, and is validating instrument performance. With its 14 spectral bands, extremely high spatial resolution, and 15 meter along-track stereo capability, ASTER is the zoom lens of the Terra satellite. The primary mission goals are to characterize the Earth's surface; and to monitor dynamic events and processes that influence habitability at human scales. ASTER's monitoring and mapping capabilities are illustrated by this series of images of the San Francisco area. The visible and near infrared image reveals suspended sediment in the bays, vegetation health, and details of the urban environment. Flying over San Francisco (3.2MB) (high-res (18.3MB)), we see the downtown, and shadows of the large buildings. Past the Golden Gate Bridge and Alcatraz Island, we cross San Pablo Bay and enter Suisun Bay. Turning south, we fly over the Berkeley and Oakland Hills. Large salt evaporation ponds come into view at the south end of San Francisco Bay. We turn northward, and approach San Francisco Airport. Rather than landing and ending our flight, we see this is as only the beginning of a 6 year mission to better understand the habitability of the world on which we live. For more information: ASTER images through Visible Earth ASTER Web Site Image courtesy of MITI, ERSDAC, JAROS, and the U.S./Japan ASTER Science Team

  13. Summary of suspended-sediment concentration data, San Francisco Bay, California, Water Year 2003

    USGS Publications Warehouse

    Buchanan, Paul A.; Ganju, Neil K.

    2005-01-01

    Suspended-sediment concentration data were collected in San Francisco Bay during water year 2003 (October 1, 2002-September 30, 2003). Optical sensors and water samples were used to monitor suspended-sediment concentration at two sites in Suisun Bay, three sites in San Pablo Bay, one site in Central San Francisco Bay, and three sites in South San Francisco Bay. Sensors were positioned at two depths at most sites. Water samples were collected periodically and analyzed for concentrations of suspended sediment. The results of the analyses were used to calibrate the output of the optical sensors so that a record of suspended-sediment concentrations could be derived. This report presents the data-collection methods used and summarizes the suspended-sediment concentration data collected from October 2002 through September 2003. Calibration curves and plots of edited data for each sensor also are presented.

  14. Summary of Suspended-Sediment Concentration Data, San Francisco Bay, California, Water Year 2001

    USGS Publications Warehouse

    Buchanan, Paul A.; Ganju, Neil K.

    2003-01-01

    Suspended-sediment concentration data were collected in San Francisco Bay during water year 2001 (October 1, 2000-September 30, 2001). Optical backscatterance sensors and water samples were used to monitor suspended sediment at two sites in Suisun Bay, three sites in San Pablo Bay, two sites in Central San Francisco Bay, and three sites in South San Francisco Bay. Sensors were positioned at two depths at most sites. Water samples were collected periodically and were analyzed for concentrations of suspended sediment. The results of the analyses were used to calibrate the electrical output of the optical backscatterance sensors so that a record of suspended-sediment concentrations could be derived. This report presents the data-collection methods used and summarizes the suspended-sediment concentration data collected from October 2000 through September 2001. Calibration curves and plots of edited data for each sensor also are presented.

  15. Summary of Suspended-Sediment Concentration Data, San Francisco Bay, California, Water Year 2002

    USGS Publications Warehouse

    Buchanan, Paul A.; Ganju, Neil K.

    2004-01-01

    Suspended-sediment concentration data were collected in San Francisco Bay during water year 2002 (October 1, 2001-September 30, 2002). Optical backscatterance sensors and water samples were used to monitor suspended sediment at two sites in Suisun Bay, three sites in San Pablo Bay, two sites in Central San Francisco Bay, and three sites in South San Francisco Bay. Sensors were positioned at two depths at most sites. Water samples were collected periodically and were analyzed for concentrations of suspended sediment. The results of the analyses were used to calibrate the electrical output of the optical backscatterance sensors so that a record of suspended-sediment concentrations could be derived. This report presents the data-collection methods used and summarizes the suspended-sediment concentration data collected from October 2001 through September 2002. Calibration curves and plots of edited data for each sensor also are presented.

  16. Summary of Suspended-Sediment Concentration Data, San Francisco Bay, California, Water Year 2005

    USGS Publications Warehouse

    Buchanan, Paul A.; Lionberger, Megan A.

    2007-01-01

    Suspended-sediment concentration data were collected by the U.S. Geological Survey in San Francisco Bay during water year 2005 (October 1, 2004-September 30, 2005). Optical sensors and water samples were used to monitor suspended-sediment concentration at two sites in Suisun Bay, three sites in San Pablo Bay, two sites in Central San Francisco Bay, and three sites in South San Francisco Bay. Sensors were positioned at two depths at most sites. Water samples were collected periodically and analyzed for concentrations of suspended sediment. The results of the analyses were used to calibrate the output of the optical sensors so that a record of suspended-sediment concentrations could be derived. This report presents the data-collection methods used and summarizes, in graphs, the suspended-sediment concentration data collected from October 2004 through September 2005. Calibration curves and plots of the processed data for each sensor also are presented.

  17. Ancient blue oaks reveal human impact on San Francisco Bay salinity

    USGS Publications Warehouse

    Stahle, David W.; Therrell, Matthew D.; Cleaveland, Malcolm K.; Cayan, Daniel R.; Dettinger, Michael D.; Knowles, Noah

    2001-01-01

    San Francisco Bay is one of the most important estuaries on the west coast of the Americas. Its water quality is controlled primarily by streamflow from the Sacramento and San Joaquin rivers. In fact, freshwater inflow from the Sacramento-San Joaquin Delta explains 86% of the salinity variability at the mouth of the San Francisco Bay estuary [Peterson et al., 1989]. The massive diversion of streamflow by the California State Water Project and the Central Valley Project, part of the largest manmade water control system on Earth [Reisner, 1988], has raised salinity in the estuary on daily, seasonal, and annual timescales [Nichols et al., 1986; Peterson et al., 1989].

  18. Summary of suspended-sediment concentration data, San Francisco Bay, California, water year 1999

    USGS Publications Warehouse

    Buchanan, Paul A.; Ruhl, Catherine A.

    2001-01-01

    Suspended-sediment concentration data were collected in San Francisco Bay during water year 1999 (October 1, 1998-September 30, 1999). Optical backscatterance sensors and water samples were used to monitor suspended sediment at one site in Suisun Bay, three sites in San Pablo Bay, two sites in Central San Francisco Bay, and three sites in South San Francisco Bay. Sensors were positioned at two depths at most sites. Water samples were collected periodically and were analyzed for concentrations of suspended sediment. The results of the analyses were used to calibrate the electrical output of the optical backscatterance sensors. This report presents the data-collection methods used and summarizes the suspended-sediment concentration data collected from October 1998 through September 1999. Calibration plots and plots of edited data for each sensor also are presented.

  19. Summary of suspended-sediment concentration data, San Francisco Bay, California, water year 2000

    USGS Publications Warehouse

    Buchanan, Paul A.; Ganju, Neil K.

    2002-01-01

    Suspended-sediment concentration data were collected in San Francisco Bay during water year 2000 (October 1, 1999?September 30, 2000). Optical backscatterance sensors and water samples were used to monitor suspended sediment at one site in Suisun Bay, three sites in San Pablo Bay, two sites in Central San Francisco Bay, and three sites in South San Francisco Bay. Sensors were positioned at two depths at most sites. Water samples were collected periodically and were analyzed for concentrations of suspended sediment. The results of the analyses were used to calibrate the electrical output of the optical backscatterance sensors. This report presents the data-collection methods and summarizes the suspended-sediment concentration data collected from October 1999 through September 2000. Calibration plots and plots of edited data for each sensor also are presented.

  20. Summary of suspended-solids concentration data, San Francisco Bay, California, water year 1994

    USGS Publications Warehouse

    Buchanan, P.A.; Schoellhamer, D.H.; Sheipline, R.C.

    1996-01-01

    Suspended-solids concentration data were collected in San Francisco Bay during water year 1994. Optical backscatterance sensors and water samples were used to monitor suspended solids continuously at two sites in Suisun Bay, two sites in Central San Francisco Bay, and three sites in South San Francisco Bay. Sensors were positioned at two depths at each site. In addition, a shallow-water instrument package was deployed in South San Francisco Bay three times for periods of several weeks to measure suspended-solids concentration and water velocity. Water samples were collected periodically and were analyzed for concentrations of suspended solids. The results of the analyses were used to calibrate the electrical output of the optical backscatterance sensors. This report presents the data-collection methods used and summarizes the suspended-solids concentration data collected from October 1993 through September 1994. Calibration plots and edited data for each sensor also are presented.

  1. Lithologic and physicochemical properties and hydraulics of flow in and near the freshwater/saline-water transition zone, San Antonio segment of the Edwards aquifer, south-central Texas, based on water-level and borehole geophysical log data, 1999-2007

    USGS Publications Warehouse

    Lambert, Rebecca B.; Hunt, Andrew G.; Stanton, Gregory P.; Nyman, Michael B.

    2010-01-01

    The freshwater zone of the San Antonio segment of the Edwards aquifer in south-central Texas (hereinafter, the Edwards aquifer) is bounded to the south and southeast by a zone of transition from freshwater to saline water (hereinafter, the transition zone). The boundary between the two zones is the freshwater/saline-water interface (hereinafter, the interface), defined as the 1,000-milligrams per liter dissolved solids concentration threshold. This report presents the findings of a study, done by the U.S. Geological Survey in cooperation with the San Antonio Water System, to obtain lithologic properties (rock properties associated with known stratigraphic units) and physicochemical properties (fluid conductivity and temperature) and to analyze the hydraulics of flow in and near the transition zone of the Edwards aquifer on the basis of water-level and borehole geophysical log data collected from 15 monitoring wells in four transects during 1999-2007. No identifiable relation between conductivity values from geophysical logs in monitoring wells in all transects and equivalent freshwater heads in the wells at the times the logs were run is evident; and no identifiable relation between conductivity values and vertical flow in the boreholes concurrent with the times the logs were run is evident. The direction of the lateral equivalent freshwater head gradient and thus the potential lateral flow at the interface in the vicinity of the East Uvalde transect fluctuates between into and out of the freshwater zone, depending on recharge and withdrawals. Whether the prevailing direction on average is into or out of the freshwater zone is not clearly indicated. Equivalent freshwater head data do not indicate a prevailing direction of the lateral gradient at the interface in the vicinity of the Tri-County transect. The prevailing direction on average of the lateral gradient and thus potential lateral flow at the interface in the vicinity of the Kyle transect likely is from the

  2. Microbial biogeography of San Francisco Bay sediments

    NASA Astrophysics Data System (ADS)

    Lee, J. A.; Francis, C. A.

    2014-12-01

    The largest estuary on the west coast of North America, San Francisco Bay is an ecosystem of enormous biodiversity, and also enormous human impact. The benthos has experienced dredging, occupation by invasive species, and over a century of sediment input as a result of hydraulic mining. Although the Bay's great cultural and ecological importance has inspired numerous surveys of the benthic macrofauna, to date there has been almost no investigation of the microbial communities on the Bay floor. An understanding of those microbial communities would contribute significantly to our understanding of both the biogeochemical processes (which are driven by the microbiota) and the physical processes (which contribute to microbial distributions) in the Bay. Here, we present the first broad survey of bacterial and archaeal taxa in the sediments of the San Francisco Bay. We conducted 16S rRNA community sequencing of bacteria and archaea in sediment samples taken bimonthly for one year, from five sites spanning the salinity gradient between Suisun and Central Bay, in order to capture the effect of both spatial and temporal environmental variation on microbial diversity. From the same samples we also conducted deep sequencing of a nitrogen-cycling functional gene, nirS, allowing an assessment of evolutionary diversity at a much finer taxonomic scale within an important and widespread functional group of bacteria. We paired these sequencing projects with extensive geochemical metadata as well as information about macrofaunal distribution. Our data reveal a diversity of distinct biogeographical patterns among different taxa: clades ubiquitous across sites; clades that respond to measurable environmental drivers; and clades that show geographical site-specificity. These community datasets allow us to test the hypothesis that salinity is a major driver of both overall microbial community structure and community structure of the denitrifying bacteria specifically; and to assess

  3. San Jose Accord: energy aid or petroleum-marketing strategy

    SciTech Connect

    Not Available

    1982-09-30

    The San Jose Accord was signed in San Jose, Costa Rica on August 3, 1980 by the Presidents of Venezuela and Mexico, whereby the two countries mutually committed to supply the net imported domestic oil consumption of several Central American and Caribbean countries. Countries initially participating in the program are: Barbados, Costa Rica, Dominican Republic, El Salvador, Guatemala, Honduras, Jamaica, Nicaragua, and Panama. Seven eastern Caribbean countries were to meet on October 7 to petition for inclusion in the Accord, namely: Antigua, St. Kitt/Nevis, Montserrat, Dominica, St. Lucia, St. Vincent, and Grenada. The official language of the Accord is presented, and the operative status of the Accord two years after signing is discussed. Specific briefs about some of the individual countries in the Accord are included. The fuel price/tax series for the Western Hemisphere countries is updated.

  4. California State Waters Map Series: offshore of San Gregorio, California

    USGS Publications Warehouse

    Cochrane, Guy R.; Dartnell, Peter; Greene, H. Gary; Watt, Janet T.; Golden, Nadine E.; Endris, Charles A.; Phillips, Eleyne L.; Hartwell, Stephen R.; Johnson, Samuel Y.; Kvitek, Rikk G.; Erdey, Mercedes D.; Bretz, Carrie K.; Manson, Michael W.; Sliter, Ray W.; Ross, Stephanie L.; Dieter, Bryan E.; Chin, John L.; Cochran, Susan A.; Cochrane, Guy R.; Cochran, Susan A.

    2014-01-01

    the northern and southern parts of the map area are the result of right-lateral motion on strands of the San Gregorio Fault system. In the south, headlands near Pescadero Point have been uplifted by motion along the west strand of the San Gregorio Fault (also called the Frijoles Fault), which separates rocks of the Pigeon Point Formation south of the fault from rocks of the Purisima Formation north of the fault. The regional uplift in this map area has caused relatively shallow water depths within California's State Waters and, thus, little accommodation space for sediment accumulation. Sediment is observed offshore in the central part of the map area, in the shelter of the headlands north of the east strand of the San Gregorio Fault (also called the Coastways Fault) around Miramontes Point (about 5 km north of the map area) and also on the outer half of the California's State Waters shelf in the south where depths exceed 40 m. Sediment in the outer shelf of California's State Waters is rippled, indicating some mobility. The Offshore of San Gregorio map area lies within the cold-temperate biogeographic zone that is called either the "Oregonian province" or the "northern California ecoregion." This biogeographic province is maintained by the long-term stability of the southward-flowing California Current, an eastern limb of the North Pacific subtropical gyre that flows from Oregon to Baja California. At its midpoint off central California, the California Current transports subarctic surface (0–500 m deep) waters southward, about 150 to 1,300 km from shore. Seasonal northwesterly winds that are, in part, responsible for the California Current, generate coastal upwelling. The south end of the Oregonian province is at Point Conception (about 350 km south of the map area), although its associated phylogeographic group of marine fauna may extend beyond to the area offshore of Los Angeles in southern California. The ocean off of central California has experienced a warming

  5. Three-dimensional upper crustal velocity structure beneath San Francisco Peninsula, California

    USGS Publications Warehouse

    Parsons, T.; Zoback, M.L.

    1997-01-01

    This paper presents new seismic data from, and crustal models of the San Francisco Peninsula. In much of central California the San Andreas fault juxtaposes the Cretaceous granitic Salinian terrane on its west and the Late Mesozoic/Early Tertiary Franciscan Complex on its east. On San Francisco Peninsula, however, the present-day San Andreas fault is completely within a Franciscan terrane, and the Pilarcitos fault, located southwest of the San Andreas, marks the Salinian-Franciscan boundary. This circumstance has evoked two different explanations: either the Pilarcitos is a thrust fault that has pushed Franciscan rocks over Salinian rocks or the Pilarcitos is a transform fault that has accommodated significant right-lateral slip. In an effort to better resolve the subsurface structure of the peninsula faults, we established a temporary network of 31 seismographs arrayed across the San Andreas fault and the subparallel Pilarcitos fault at ???1-2 km spacings. These instruments were deployed during the first 6 months of 1995 and recorded local earthquakes, air gun sources set off in San Francisco Bay, and explosive sources. Travel times from these sources were used to augment earthquake arrival times recorded by the Northern California Seismic Network and were inverted for three-dimensional velocity structure. Results show lateral velocity changes at depth (???0.5-7 km) that correlate with downward vertical projections of the surface traces of the San Andreas and Pilarcitos faults. We thus interpret the faults as high-angle to vertical features (constrained to a 70??-110?? dip range). From this we conclude that the Pilarcitos fault is probably an important strike-slip fault that accommodated much of the right-lateral plate boundary strain on the peninsula prior to the initiation of the modern-day San Andreas fault in this region sometime after about 3.0 m.y. ago.

  6. Stratigraphic relationships of Cretaceous and early Tertiary rocks of a part of northwestern San Juan basin

    USGS Publications Warehouse

    Baltz, Elmer Harold

    1953-01-01

    The Bridge Timber Mountain area in south-central La Plata County, southwestern Colorado lies mostly in the northwestern part of the Central San Juan Basin but contains a segment of the bounding Hogback 'monocline' and Four-Corners platform. The area contains rocks of late Cretaceous through early Eocene age, as well as Pliocene, Pleistocene, and Recent terrace and pediment gravels. The Pictured Cliffs sandstone of late Montana age is the latest marine formation present. Retreat of the Cretaceous seas from the area marked the beginning of Laramide orogenic activity and the earliest stages of deformation which produced the modern San Juan Basin. The Fruitland formation and Kirtland shale were deposited in brackish water and on coastal plains left by the retreating Cretaceous sea. Beds of the Farmington sandstone member and upper shale member of the Kirtland shale show evidence of a new source of sediments to the north or northeast distinct from the southwestern source area of older Cretaceous rocks. The McDermott 'formation', composed mainly of volcanic debris, is considered to be a local lower member of the Animas formation. Beds of the upper member of the Animas formation of Cretaceous and Paleocene age are considered to extend entirely across the area and into New Mexico. Overstep of higher sandstone and shale beds of the upper member across lower conglomeratic beds shows that folding on the Hogback 'monocline' began during deposition of the upper member. Beds of the upper member of the Animas formation grade laterally southward into Paleocene beds of the Nacimiento formation, but upper Nacimiento beds overstep folded beds of the Animas formation on the Hogback 'monocline' at the north end of Bridge Timber Mountain. The San Jose formation of Paleocene and Eocene age is conformable with the Nacimiento formation except at the north end of Bridge Timber Mountain where upper San Jose beds overstep all older tilted beds down to the Fruitland formation. The heavy

  7. California State Waters Map Series: offshore of San Gregorio, California

    USGS Publications Warehouse

    Cochrane, Guy R.; Dartnell, Peter; Greene, H. Gary; Watt, Janet T.; Golden, Nadine E.; Endris, Charles A.; Phillips, Eleyne L.; Hartwell, Stephen R.; Johnson, Samuel Y.; Kvitek, Rikk G.; Erdey, Mercedes D.; Bretz, Carrie K.; Manson, Michael W.; Sliter, Ray W.; Ross, Stephanie L.; Dieter, Bryan E.; Chin, John L.; Cochran, Susan A.; Cochrane, Guy R.; Cochran, Susan A.

    2014-01-01

    the northern and southern parts of the map area are the result of right-lateral motion on strands of the San Gregorio Fault system. In the south, headlands near Pescadero Point have been uplifted by motion along the west strand of the San Gregorio Fault (also called the Frijoles Fault), which separates rocks of the Pigeon Point Formation south of the fault from rocks of the Purisima Formation north of the fault. The regional uplift in this map area has caused relatively shallow water depths within California's State Waters and, thus, little accommodation space for sediment accumulation. Sediment is observed offshore in the central part of the map area, in the shelter of the headlands north of the east strand of the San Gregorio Fault (also called the Coastways Fault) around Miramontes Point (about 5 km north of the map area) and also on the outer half of the California's State Waters shelf in the south where depths exceed 40 m. Sediment in the outer shelf of California's State Waters is rippled, indicating some mobility. The Offshore of San Gregorio map area lies within the cold-temperate biogeographic zone that is called either the "Oregonian province" or the "northern California ecoregion." This biogeographic province is maintained by the long-term stability of the southward-flowing California Current, an eastern limb of the North Pacific subtropical gyre that flows from Oregon to Baja California. At its midpoint off central California, the California Current transports subarctic surface (0–500 m deep) waters southward, about 150 to 1,300 km from shore. Seasonal northwesterly winds that are, in part, responsible for the California Current, generate coastal upwelling. The south end of the Oregonian province is at Point Conception (about 350 km south of the map area), although its associated phylogeographic group of marine fauna may extend beyond to the area offshore of Los Angeles in southern California. The ocean off of central California has experienced a warming

  8. Mineral resources of the San Rafael Swell Wilderness Study Areas, including Muddy Creek, Crack Canyon, San Rafael Reef, Mexican Mountain, and Sids Mountain Wilderness Study Areas, Emery County, Utah

    SciTech Connect

    Bartsch-Winkler, S.; Dickerson, R.P.; Barton, H.W.; McCafferty, A.E.; Grauch, V.J.S.; Koyuncu, H.; Lee, K.; Duval, J.S. ); Munts, S.R.; Benjamin, D.A.; Close, T.J.; Lipton, D.A.; Neumann, T.R.; Willet, S.L. )

    1990-09-01

    This paper reports on the San Rafael Swell Wilderness Study areas, which includes the Muddy Creek, Crack Canyon, San Rafael Reef, Mexican Mountain, and Sids Mountain Wilderness Study Areas, in Emery County, south-central Utah. Within and near the Crack Canyon Wilderness Study Area are identified subeconomic uranium and vanadium resources. Within the Carmel Formation are inferred subeconomic resources of gypsum in the Muddy Creek, San Rafael Reef, and Sids Mountain Wilderness Study Areas. Other commodities evaluated include geothermal energy, gypsum, limestone, oil and gas, sand and gravel, sandstone, semiprecious gemstones, sulfur petrified wood, and tar sand.

  9. Soil degradation in farmlands of California’s San Joaquin Valley resulting from drought-induced land-use changes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Irrigation in California’s Central Valley (USA) has decreased significantly due to water shortages resulting from the current drought, which began in 2010. In particular, fallow fields in the west side of the San Joaquin Valley (WSJV), which is the southwest portion of the Central Valley, increased ...

  10. Shelving plans, elevations, and sections. San Bernardino Valley Union Junior ...

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

    Shelving plans, elevations, and sections. San Bernardino Valley Union Junior College, Science Building. Howard E. Jones, Architect, San Bernardino, California. Sheet 9, job no. 311. Scale 1.2 inch to the foot. February 15, 1927. - San Bernardino Valley College, Life Science Building, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  11. South elevation and main floor plan. San Bernardino Valley Union ...

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

    South elevation and main floor plan. San Bernardino Valley Union Junior College, Science Building. Includes chemistry and botany departments. Howard E. Jones, Architect, San Bernardino, California. Sheet 2, job no. 311. Scale 1/8 inch to the foot. February 15, 1927. - San Bernardino Valley College, Life Science Building, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  12. South entrance, plan, section, & detail. San Bernardino Valley Union ...

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

    South entrance, plan, section, & detail. San Bernardino Valley Union Junior College, Science Building. Detailed drawings of tile work, wrought iron, and art stone, Howard E. Jones, Architect, San Bernardino, California. Sheet 6, job no. 311. Scale 1.2 inch to the foot. February 15, 1927. - San Bernardino Valley College, Life Science Building, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  13. 112. Dennis Hill, Photographer January 1998 VIEW OF SAN FRANCISCO ...

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

    112. Dennis Hill, Photographer January 1998 VIEW OF SAN FRANCISCO VIADUCT (RIGHT), UPPER DECK OFF-RAMP (LEFT), AND LOWER DECK ON-RAMP FROM TRANSBAY TERMINAL BUS LOOP, FACING NORTHEAST. - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  14. 36. Post Engineer Office, Presidio of San Francisco. Plot Plan, ...

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

    36. Post Engineer Office, Presidio of San Francisco. Plot Plan, Letterman Army Hospital, San Francisco, Calif. 1958. SHOWING LOCATION OF BUILDINGS 1006 AND 1049 IN LETTERMAN HOSPITAL COMPLEX IN 1958. - Presidio of San Francisco, Letterman General Hospital, Building No. 27, Letterman Hospital Complex, Edie Road, San Francisco, San Francisco County, CA

  15. The San Francisco Peace Treaty: The Cold War and the Peace Process.

    ERIC Educational Resources Information Center

    Brunette, Rachel

    International treaties have played a central role in diplomatic history since the rise of the modern nation state. Since the end of World War II, more treaties have been formed than in the preceding four centuries. The year 2001 marks the 50th anniversary of the San Francisco Peace Treaty. This unit provides students with historical knowledge of…

  16. Building from a sustainability viewpoint: New headquarters for San Luis Obispo Solar Group

    SciTech Connect

    Haggard, K.

    1996-10-01

    The Highway 41 fire of 1994 in Central California destroyed the San Luis Obispo Solar Group complex. This destruction offered them an opportunity to update their approach to sustainability while designing and building new facilities for the firm. This paper will describe this approach and the design characteristics of this project.

  17. Long Range Development Plan, University of California, San Diego, October 1963.

    ERIC Educational Resources Information Center

    Alexander, Robert E.

    The academic and physical development plans of the University of California at San Diego are outlined. Facilities for 27,500 anticipated students are divided into twelve colleges of about 2300 students each. The twelve colleges are arranged into three clusters of four each, grouped around the central academic and administrative facilities, in…

  18. An Analysis of Certain Selected Causes of Poverty in San Miguel County.

    ERIC Educational Resources Information Center

    Knowlton, Clark S.

    San Miguel County, one of the larger, older, and more predominantly Spanish American counties in New Mexico, is located in the north central section of the State. Marked by varied topographical and climatic characteristics, the county was once one of the more prosperous and densely populated areas of the State. Today it suffers from high rates of…

  19. [Dental fluorosis in San Luis Potosi and its solution alternatives (pilot study)].

    PubMed

    Sánchez Prieto, M; Vázquez Guerrero, V; Silva Romo, E; Moreno Vélez, R; Ochoa Flores, L; Hernández, M J

    1988-12-01

    A study exposing the situation affecting the population of San Luis Potosí in central México, caused by dental fluorosis. Findings point to the need of implementing devices capable of regulating the concentrations of Fluorine ion (generating the efficient prevention of dental cavity incidence), to maintain them at optimal levels and without deletereal effects.

  20. POINT-OF-USE TREATMENT OF DRINKING WATER IN SAN YSIDRO, NM

    EPA Science Inventory

    This study was conducted to determine whether point-of-use (POU) reverse osmosis (RO) units could satisfactorily function in lieu of central treatment to remove arsenic and fluoride from the drinking water supply of San Ysidro, NM. POU treatment was evaluated for removal efficien...

  1. San Francisco protest against meeting disruptions.

    PubMed

    James, J S

    1995-04-01

    Twenty-five leading AIDS activists and organizations in San Francisco have published a letter asking ACT UP San Francisco to stop disrupting meetings. ACT UP San Francisco has targeted public forums to protest the pharmaceutical companies' prolonged trials, claiming that it is unethical to use sick people to test the effectiveness of drugs. Their staged protests often result in HIV-positive persons not getting the treatment information they need.

  2. Deformation across the Pacific-North America plate boundary near San Francisco, California

    USGS Publications Warehouse

    Prescott, W.H.; Savage, J.C.; Svarc, J.L.; Manaker, D.

    2001-01-01

    We have detected a narrow zone of compression between the Coast Ranges and the Great Valley, and we have estimated slip rates for the San Andreas, Rodgers Creek, and Green Valley faults just north of San Francisco. These results are based on an analysis of campaign and continuous Global Positioning System (GPS) data collected between 1992 and 2000 in central California. The zone of compression between the Coast Ranges and the Great Valley is 25 km wide. The observations clearly show 3.8??1.5 mm yr-1 of shortening over this narrow zone. The strike slip components are best fit by a model with 20.8??1.9 mm yr-1 slip on the San Andreas fault, 10.3??2.6 mm yr-1 on the Rodgers Creek fault, and 8.1??2.1 mm yr-1 on the Green Valley fault. The Pacific-Sierra Nevada-Great Valley motion totals 39.2??3.8 mm yr-1 across a zone that is 120 km wide (at the latitude of San Francisco). Standard deviations are one ??. The geodetic results suggest a higher than geologic rate for the Green Valley fault. The geodetic results also suggest an inconsistency between geologic estimates of the San Andreas rate and seismologic estimates of the depth of locking on the San Andreas fault. The only convergence observed is in the narrow zone along the border between the Great Valley and the Coast Ranges.

  3. Heat flow and energetics of the San Andreas fault zone.

    USGS Publications Warehouse

    Lachenbruch, A.H.; Sass, J.H.

    1980-01-01

    Approximately 100 heat flow measurements in the San Andreas fault zone indicate 1) there is no evidence for local frictional heating of the main fault trace at any latitude over a 1000-km length from Cape Mendocino to San Bernardino, 2) average heat flow is high (ca.2 HFU, ca.80 mW m-2) throughout the 550-km segment of the Coast Ranges that encloses the San Andreas fault zone in central California; this broad anomaly falls off rapidly toward the Great Valley to the east, and over a 200-km distance toward the Mendocino Triple Junction to the northwest. As others have pointed out, a local conductive heat flow anomaly would be detectable unless the frictional resistance allocated to heat production on the main trace were less than 100 bars. Frictional work allocated to surface energy of new fractures is probably unimportant, and hydrologic convection is not likely to invalidate the conduction assumption, since the heat discharge by thermal springs near the fault is negligible. -Authors

  4. 78 FR 77597 - Safety Zone; Allied PRA-Solid Works, San Diego Bay; San Diego, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-24

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Allied PRA-Solid Works, San Diego Bay; San Diego, CA AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is... Giacomo Terrizzi, Waterways Management, U.S. Coast Guard Sector San Diego, Coast Guard; telephone...

  5. 76 FR 81371 - Safety Zone; San Francisco New Year's Eve Fireworks Display, San Francisco, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-28

    ... SECURITY Coast Guard 33 CFR Part 165 Safety Zone; San Francisco New Year's Eve Fireworks Display, San... Guard will enforce the safety zone for the annual San Francisco New Year's Eve Fireworks Display in the... Francisco New Year's Eve Fireworks Display in 33 CFR 165.1191. Under the provisions of 33 CFR...

  6. 78 FR 34123 - Notice of Inventory Completion: San Francisco State University NAGPRA Program, San Francisco, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-06

    ... National Park Service Notice of Inventory Completion: San Francisco State University NAGPRA Program, San Francisco, CA AGENCY: National Park Service, Interior. ACTION: Notice. SUMMARY: The San Francisco State... control of these human remains and associated funerary objects should submit a written request to the...

  7. 75 FR 15611 - Safety Zone; United Portuguese SES Centennial Festa, San Diego Bay, San Diego, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-30

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; United Portuguese SES Centennial Festa, San Diego Bay, San Diego, CA AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a safety zone on the navigable waters of the San Diego Bay in support of...

  8. Volcano hazards in the San Salvador region, El Salvador

    USGS Publications Warehouse

    Major, J.J.; Schilling, S.P.; Sofield, D.J.; Escobar, C.D.; Pullinger, C.R.

    2001-01-01

    San Salvador volcano is one of many volcanoes along the volcanic arc in El Salvador (figure 1). This volcano, having a volume of about 110 cubic kilometers, towers above San Salvador, the country’s capital and largest city. The city has a population of approximately 2 million, and a population density of about 2100 people per square kilometer. The city of San Salvador and other communities have gradually encroached onto the lower flanks of the volcano, increasing the risk that even small events may have serious societal consequences. San Salvador volcano has not erupted for more than 80 years, but it has a long history of repeated, and sometimes violent, eruptions. The volcano is composed of remnants of multiple eruptive centers, and these remnants are commonly referred to by several names. The central part of the volcano, which contains a large circular crater, is known as El Boquerón, and it rises to an altitude of about 1890 meters. El Picacho, the prominent peak of highest elevation (1960 meters altitude) to the northeast of the crater, and El Jabali, the peak to the northwest of the crater, represent remnants of an older, larger edifice. The volcano has erupted several times during the past 70,000 years from vents central to the volcano as well as from smaller vents and fissures on its flanks [1] (numerals in brackets refer to end notes in the report). In addition, several small cinder cones and explosion craters are located within 10 kilometers of the volcano. Since about 1200 A.D., eruptions have occurred almost exclusively along, or a few kilometers beyond, the northwest flank of the volcano, and have consisted primarily of small explosions and emplacement of lava flows. However, San Salvador volcano has erupted violently and explosively in the past, even as recently as 800 years ago. When such eruptions occur again, substantial population and infrastructure will be at risk. Volcanic eruptions are not the only events that present a risk to local

  9. Structural model of the San Bernardino basin, California, from analysis of gravity, aeromagnetic, and seismicity data

    USGS Publications Warehouse

    Anderson, M.; Matti, J.; Jachens, R.

    2004-01-01

    The San Bernardino basin is an area of Quaternary extension between the San Jacinto and San Andreas Fault zones in southern California. New gravity data are combined with aeromagnetic data to produce two- and three-dimensional models of the basin floor. These models are used to identify specific faults that have normal displacements. In addition, aeromagnetic maps of the basin constrain strike-slip offset on many faults. Relocated seismicity, focal mechanisms, and a seismic reflection profile for the basin area support interpretations of the gravity and magnetic anomalies. The shape of the basin revealed by our interpretations is different from past interpretations, broadening its areal extent while confining the deepest parts to an area along the modern San Jacinto fault, west of the city of San Bernardino. Through these geophysical observations and related geologic information, we propose a model for the development of the basin. The San Jacinto fault-related strike-slip displacements started on fault strands in the basin having a stepping geometry thus forming a pull-apart graben, and finally cut through the graben in a simpler, bending geometry. In this model, the San Bernardino strand of the San Andreas Fault has little influence on the formation of the basin. The deep, central part of the basin resembles classic pull-apart structures and our model describes a high level of detail for this structure that can be compared to other pull-apart structures as well as analog and numerical models in order to better understand timing and kinematics of pull-apart basin formation. Copyright 2004 by the American Geophysical Union.

  10. Late Cenozoic geology of Cajon Pass: implications for tectonics and sedimentation along the San Andreas fault

    SciTech Connect

    Weldon, R.J. II

    1986-01-01

    The geology in Cajon Pass, southern California, provides a detailed history of strike-slip activity on the San Andreas fault, compressional deformation associated with the uplift of the central Transverse Ranges and an excellent Cenozoic record of syntectonic sedimentation. Age control was established in all of the sediments deposited since the Early Miocene, using biostratigraphy, magnetostratigraphy, fission-track dating of volcanic ashes, radiocarbon dating, soil development, and the relative stratigraphic and geomorphic position of the units. Detailed mapping revealed that tectonic deformation and sedimentation styles varied through time, reflecting the evolution of the San Andreas fault zone within the Pacific-North American plate boundary and climatic changes. Three distinct phases of the uplift of the San Bernardino Mountains have been recognized, suggesting a long-term interaction between the strike-slip activity on the San Andreas system and the compressional tectonics of the Transverse Ranges. Uplift began in the late Miocene, paused during the Pliocene, recommenced in the earliest Pleistocene and culminated in the late Pleistocene. The average slip rate across the combined San Andreas and San Jacinto faults was 37.5 +/- 2 mm/yr during the Quaternary Period. The Holocene slip rate on the San Andreas fault in Cajon Pass was determined to be 24.5 +/- 3.5 mm/yr. This investigation indicates that the last earthquake associated wit rupture on the San Andreas fault in Cajon Pass occurred around 1700 AD and that the average recurrence interval between earthquakes is between 150 and 200 years. A kinematic model was constructed from the structural and slip rate data developed here that produces internally consistent motions for all of the fault-bounded blocks in southern California.

  11. Flood control failure: San Lorenzo River, California

    NASA Astrophysics Data System (ADS)

    Griggs, Gary B.; Paris, Lance

    1982-09-01

    The San Lorenzo River on the central California coast was the site of a major US Army Corps of Engineers flood control project in 1959. By excavating the channel below its natural grade and constructing levees, the capacity of the river was increased in order to contain approximately the 100 year flood. Production and transport of large volumes of sediment from the river's urbanizing watershed has filled the flood control project with sand and silt. The natural gradient has been re-established, and flood protection has been reduced to containment of perhaps the 30 year flood. In order for the City of Santa Cruz, which is situated on the flood plain, to be protected from future flooding,it must either initiate an expensive annual dredging program, or replan and rebuild the inadequately designed flood control channel. It has become clear, here and elsewhere, that the problem of flooding cannot simply be resolved by engineering. Large flood control projects provide a false sense of security and commonly produce unexpected channel changes.

  12. 1. GENERAL VIEW OF COMPLEX (drawing from History of San ...

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

    1. GENERAL VIEW OF COMPLEX (drawing from History of San Diego County, California, published 1883. Photocopy 1975 by Bert Shankland, San Diego). - Johnson-Taylor Ranch House, Black Mountain Road vicinity, Rancho Penasquitos, San Diego County, CA

  13. 2. Historic American Buildings Photo by Muybridge, Gleason Collection San ...

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

    2. Historic American Buildings Photo by Muybridge, Gleason Collection San Francisco College for Women Ca. 1870 CONSTRUCTION VIEW FROM SOUTH - U. S. Branch Mint, Mission & Fifth Streets, San Francisco, San Francisco County, CA

  14. 2. COURTYARD, 1890 (photograph from Title Insurance Collection, San Diego ...

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

    2. COURTYARD, 1890 (photograph from Title Insurance Collection, San Diego Historical Society. Photocopy 1975 by Bert Shankland, San Diego). - Johnson-Taylor Ranch House, Black Mountain Road vicinity, Rancho Penasquitos, San Diego County, CA

  15. 8. GENERAL VIEW FROM SOUTHEAST (Title Insurance Co. collection, San ...

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

    8. GENERAL VIEW FROM SOUTHEAST (Title Insurance Co. collection, San Diego Historical Society). Historical view, no date, photocopied for HABS, 1975 - Long-Waterman House, 2408 First Avenue, San Diego, San Diego County, CA

  16. Metamorphism of San Antonio Terrane metapelites, San Gabriel Mountains, California

    SciTech Connect

    Archuleta, L.; Ishimatsu, J.; Schneiderman, J.S. . Geology Dept.)

    1993-04-01

    Pelitic schists and gneisses from the San Antonio terrane in the eastern San Gabriel Mountains consist of garnet, biotite, plagioclase, quartz, sillimanite, cordierite, hercynite [+-] alkali feldspar. Large garnet porphyroblasts contain quartz, plagioclase and sillimanite inclusions. Cordierite occurs as haloes around garnet porphyroblasts and as small subgrains always associated with hercynite and together replacing sillimanite blades. Hercynite additionally appears to have nucleated on the edges of sillimanite blades. Contrary to previous investigations, hercynite appears to be a late mineral phase. Reaction textures described above have been used to calculate a set of net-transfer reactions that can be used (1) to characterize all possible exchanges of matter between minerals in the system and (2) to construct a reaction space for the system. Fourteen thin sections with large garnet porphyroblasts and abundant biotite were used for microprobe analysis. Detailed probe analyses show well-developed zoning in the plagioclase and alkali feldspar whose character varies depending on location in the thin section relative to neighboring minerals. Generally, large plagioclase porphyroblasts display normal zoning and are not as calcium-rich as plagioclase inclusions in the garnet. Garnet porphyroblasts have flat zoning profiles due to high temperatures of metamorphism. Pressures and temperatures of metamorphism have been calculated from these assemblages using garnet-biotite geothermometry and quartz-garnet-aluminosilicate-plagioclase geobarometry.

  17. Space Radar Image of San Francisco, California

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This image of San Francisco, California shows how the radar distinguishes between densely populated urban areas and nearby areas that are relatively unsettled. Downtown San Francisco is at the center and the city of Oakland is at the right across the San Francisco Bay. Some city areas, such as the South of Market, called the SOMA district in San Francisco, appear bright red due to the alignment of streets and buildings to the incoming radar beam. Various bridges in the area are also visible including the Golden Gate Bridge (left center) at the opening of San Francisco Bay, the Bay Bridge (right center) connecting San Francisco and Oakland, and the San Mateo Bridge (bottom center). All the dark areas on the image are relatively smooth water: the Pacific Ocean to the left, San Francisco Bay in the center, and various reservoirs. Two major faults bounding the San Francisco-Oakland urban areas are visible on this image. The San Andreas fault, on the San Francisco peninsula, is seen in the lower left of the image. The fault trace is the straight feature filled with linear reservoirs which appear dark. The Hayward fault is the straight feature on the right side of the image between the urban areas and the hillier terrain to the east. The image is about 42 kilometers by 58 kilometers (26 miles by 36 miles) with north toward the upper right. This area is centered at 37.83 degrees north latitude, 122.38 degrees east longitude. The image was acquired by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture (SIR-C/X-SAR) imaging radar when it flew aboard the space shuttle Endeavour on October 3, 1994. SIR-C/X-SAR, a joint mission of the German, Italian and the United States space agencies, is part of NASA's Mission to Planet Earth.

  18. Emplacement, offset history, and recent uplift of basement within the San Andreas Fault System, northeast San Gabriel Mountains, California

    NASA Astrophysics Data System (ADS)

    Kenney, Miles Douglas

    1999-11-01

    Mapping, petrography, cross-sections, structure contours, earthquake locations, and focal mechanism analogues of summed moment tensors have provided insights into the reconstruction and deformation associated with the San Andreas Fault System in the San Gabriel and Western San Bernardino Mountains (WSBM) of the Central Transverse Ranges. The San Gabriel Mountains (SGM) represent a Quaternary 'arch' that extends across the northwest trending San Andreas Fault (SAF). Mechanisms to explain the relatively large magnitudes of uplift on both sides of this relatively straight strike slip fault have been problematical. The uplift results from the interactions between the right lateral San Jacinto Fault (SJF) and SAF, and the thrust Cucamonga-Sierra Madre Faults (CF-SMF). Uplift south of the SAF occurs as the SGM Block propagates through the restraining bend at the intersection of the SJF and SAF at the surface, which has produced an antiform in the topography of the range and in the Vincent Thrust. Uplift is also due to motion on the CF-SMF. Uplift north of the SAF is attributed to an upper-crustal north-dipping subsurface restraining bend in the SAF due to the projected intersection of the CF-SMF and SJF, with the SAF. Northwest migration of the restraining bend in the Quaternary has produced a ˜1.5 km high, northeast dipping monocline in crystalline basement which is adjacent and parallel to the SAF. Reverse faults and deformation of alluvial terraces document a northwest migrating locus of compression and uplift. Toward the southeast, the subsurface restraining bend becomes a subsurface lateral ramp where the SJF intersects the SAF at depth. Crystalline basement of the Holcomb Ridge-Table Mountain 'slice' consists of a syntectonically emplaced, intercalated, north-dipping, igneous and metamorphic suite. Cretaceous igneous rocks were emplaced as tabular bodies, which now strike eastwest, and are concordant with a relatively older metasedimentary screen and para

  19. Basin structure of the San Fernando and Santa Clarita Valleys and geometry of the Northridge and San Fernando faults as determined from the Los Angeles Region Seismic Experiment, Phase II (LARSE II)

    NASA Astrophysics Data System (ADS)

    Lutter, W. J.; Ryberg, T.; Fuis, G. S.; Murphy, J. M.; Okaya, D. A.

    2001-12-01

    We acquired combined refraction and low-fold reflection data along a north-south-trending profile through the epicentral regions of the 1994 M 6.7 Northridge and 1971 M 6.7 San Fernando earthquakes as part of the Los Angeles Region Seismic Experiment, Phase II (LARSE II). The chief goal of LARSE is to image sedimentary basins and faults in the Los Angeles region to better understand and mitigate earthquake hazards associated with sedimentary basins and hidden faults. The LARSE II profile crossed the San Fernando and Santa Clarita Valleys, locations of the Northridge and San Fernando earthquakes, respectively. Refraction and reflection data show asymmetric basins beneath both valleys. Stacked wide-angle basin-bottom reflections and iso-velocity lines dip gently northward from the Santa Monica Mts, on the south margin of the San Fernando Valley, to 5-6 km below sea level in the northern part of the San Fernando Valley. Similar reflections and iso-velocity lines dip southward from the Sierra Pelona, on the north margin of the Santa Clarita Valley, to 3.5-4.5 km below sea level at the San Gabriel fault, in the central part of the Santa Clarita Valley. In both valleys, the basin-bottom reflections are generally slightly below the 5 km/s iso-velocity line, indicating that ``basement'' beneath these two valleys has velocities generally upwards of 5 km/s. In the San Fernando Valley, the basin-bottom reflections are truncated on the north by what we interpret to be the Northridge Hills blind thrust fault. In the Santa Clarita Valley, these reflections are truncated on the south at the steeply north-dipping San Gabriel fault. The region between these two faults, including the Santa Susana Mts and the southern part of the Santa Clarita Valley is characterized by complexity in both the velocity model and reflectivity. Below ~10-km depth, reflectivity is higher in the hanging walls of the Northridge and San Fernando faults than in the footwalls. The Northridge fault dips ~30o

  20. MAPP in action in San Antonio, Texas.

    PubMed

    Shields, Kathleen M; Pruski, Charles E

    2005-01-01

    San Antonio was selected as an official Mobilizing for Action through Planning and Partnerships (MAPP) demonstration site by National Association of County and City Officials in 2000. The San Antonio Metropolitan Health District, under the leadership of Dr Fernando A. Guerra, agreed to facilitate the process. The MAPP process provided the San Antonio Metropolitan Health District, the local public health authority, a defined process for community health improvement, as well as a mechanism to help bridge the gap between public health and the community. The San Antonio Metropolitan Health District organized a Core Planning Team to lead the MAPP process in April 2001. By October 2002, the Core Planning Team was expanded to a full community working group named the Alliance for Community Health in San Antonio and Bexar County (Alliance). The Alliance identified six strategic issues, which eventually became the basis of the San Antonio Community Health Improvement Plan. The strategic issues are Public Policy, Data Tracking, Healthy Lifestyles, Promoting a Sense of Community, Access to Care, and Safe Environment. San Antonio's MAPP experience has been successful in bringing together the public health system partners, and establishing public health priorities collectively. The MAPP process has resulted in the development of many new initiatives, and, most important, has opened the door to many partnership opportunities in the future. The work of the Alliance, through the MAPP process, has helped to leverage resources for public health improvement in San Antonio, and has the potential to effect positive change in public health in the future. PMID:16103814

  1. Public Library Service for San Benito County.

    ERIC Educational Resources Information Center

    McGovern, Gail

    A sparsely populated, agricultural area, San Benito County (California) provides library services in conjunction with the Hollister city library and in cooperation with the San Juan Bautista city library. Financing comes from the county general fund. There are no written goals or policy statements and no professionally trained librarians. As…

  2. Trouble Brewing in San Francisco. Policy Brief

    ERIC Educational Resources Information Center

    Buck, Stuart

    2010-01-01

    The city of San Francisco will face enormous budgetary pressures from the growing deficits in public pensions, both at a state and local level. In this policy brief, the author estimates that San Francisco faces an aggregate $22.4 billion liability for pensions and retiree health benefits that are underfunded--including $14.1 billion for the city…

  3. San Diego's High School Dropout Crisis

    ERIC Educational Resources Information Center

    Wilson, James C.

    2012-01-01

    This article highlights San Diego's dropout problem and how much it's costing the city and the state. Most San Diegans do not realize the enormous impact high school dropouts on their city. The California Dropout Research Project, located at the University of California at Santa Barbara, has estimated the lifetime cost of one class or cohort of…

  4. 27 CFR 9.56 - San Lucas.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... in section 11, T. 22 S., R. 9 E.; (19) Then west southwesterly in a straight line approximately 0.58... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false San Lucas. 9.56 Section 9... TREASURY ALCOHOL AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.56 San Lucas....

  5. 27 CFR 9.56 - San Lucas.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... in section 11, T. 22 S., R. 9 E.; (19) Then west southwesterly in a straight line approximately 0.58... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false San Lucas. 9.56 Section 9... TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.56 San Lucas....

  6. 27 CFR 9.56 - San Lucas.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... in section 11, T. 22 S., R. 9 E.; (19) Then west southwesterly in a straight line approximately 0.58... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false San Lucas. 9.56 Section 9... TREASURY ALCOHOL AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.56 San Lucas....

  7. Lithosphere-Asthenosphere interactions near the San Andreas fault.

    NASA Astrophysics Data System (ADS)

    Houlie, N.

    2015-12-01

    We decipher the strain history of the upper mantle in California through the comparison of the long-term finite strain field in the mantle and the surface strain-rate field, respectively inferred from fast polarization directions of seismic phases (SKS and SKKS), and Global Positioning System (GPS) surface velocity fields. We show that mantle strain and surface strain-rate fields are consistent in the vicinity of San Andreas Fault (SAF) in California. Such an agreement suggests that the lithosphere and strong asthenosphere have been deformed coherently and steadily since >1 Ma. We find that the crustal stress field rotates (up to 40 degrees of rotation across a 50 km distance from 50 degrees relative to the strike of the SAF, in the near-field of SAF) from San Francisco to the Central Valley. Both observations suggest that the SAF extends to depth, likely through the entire lithosphere. From Central Valley towards the Basin and Range, the orientations of GPS strain-rates, shear wave splitting measurements and seismic stress fields diverge indicating reduced coupling or/and shallow crustal extension and/or presence of frozen anisotropy.

  8. Summary of suspended-sediment concentration data, San Francisco Bay, California, water year 2008

    USGS Publications Warehouse

    Buchanan, Paul A.; Morgan, Tara L.

    2011-01-01

    Suspended-sediment concentration data were collected by the U.S. Geological Survey in San Francisco Bay during water year 2008 (October 1, 2007–September 30, 2008). Optical sensors and water samples were used to monitor suspended-sediment concentration at two sites in Suisun Bay, two sites in Central San Francisco Bay, and one site in South San Francisco Bay. Sensors were positioned at two depths at most sites to help define the vertical variability of suspended sediments. Water samples were collected periodically and analyzed for concentrations of suspended sediment. The results of the analyses were used to calibrate the output of the optical sensors so that a record of suspended-sediment concentrations could be derived. This report presents the data-collection methods used and summarizes, in graphs, the suspended-sediment concentration data collected from October 2007 through September 2008. Calibration curves and plots of the processed data for each sensor also are presented.

  9. Summary of Suspended-Sediment Concentration Data, San Francisco Bay, California, Water Year 2007

    USGS Publications Warehouse

    Buchanan, Paul A.; Morgan, Tara L.

    2010-01-01

    Suspended-sediment concentration data were collected by the U.S. Geological Survey in San Francisco Bay during water year 2007 (October 1, 2006-September 30, 2007). Optical sensors and water samples were used to monitor suspended-sediment concentration at two sites in Suisun Bay, two sites in Central San Francisco Bay, and one site in South San Francisco Bay. Sensors were positioned at two depths at most sites to help define the vertical variability of suspended sediments.Water samples were collected periodically and analyzed for concentrations of suspended sediment. The results of the analyses were used to calibrate the output of the optical sensors so that a record of suspended-sediment concentrations could be derived. This report presents the data-collection methods used and summarizes, in graphs, the suspended-sediment concentration data collected from October 2006 through September 2007. Calibration curves and plots of the processed data for each sensor also are presented.

  10. Middle Cenozoic depositional, tectonic, and sea level history of southern San Joaquin basin, California

    SciTech Connect

    Decelles, P.G.

    1988-11-01

    As a prolific producer of hydrocarbons, the San Joaquin basin in south-central California has been the subject of geological research since the late nineteenth century. Much of this research has focused on the subsurface Eocene to lower Miocene succession because of its attractive reservoir potential. Although seismic and well-log data are available in profuse quantities, the complex sedimentary architecture of the basin fill, the application of local and inconsistent stratigraphic nomenclature, and the inherent limitations of subsurface data have led to much confusion concerning the middle Cenozoic history of the basin. This paper presents a sedimentological analysis of the depositional systems in the Eocene to lower Miocene strata of the San Emigdio and Tehachapi Mountains. The various depositional systems are considered within the contexts of encompassing depositional sequences to reconstruct the middle Cenozoic depositional, tectonic, and sea level history of the southern San Joaquin basin. 14 figures, 1 table.

  11. Summary of suspended-solids concentration data, San Francisco Bay, California, Water Year 1995

    USGS Publications Warehouse

    Buchanan, P.A.; Schoellhamer, D.H.

    1996-01-01

    Suspended-solids concentration data were collected in San Francisco Bay during water year 1995 (October 1, 1994September 30, 1995). Optical backscatterance sensors and water samples were used to monitor suspended solids continuously at two sites in Suisun Bay, two sites in Central San Francisco Bay, and three sites in South San Francisco Bay. Sensors were positioned at two depths at each site. Water samples were collected periodically and were analyzed for concentrations of suspended solids. The results of the analyses were used to calibrate the electrical output of the optical backscatterance sensors. This report presents the data-collection methods used and summarizes the suspended-solids concentration data collected from October 1994 through September 1995. Calibration plots and edited data for each sensor also are presented.

  12. Summary of suspended-solids concentration data, San Francisco Bay, California, water year 1996

    USGS Publications Warehouse

    Buchanan, Paul A.; Schoellhamer, David H.

    1998-01-01

    Suspended-solids concentration data were collected in San Francisco Bay during water year 1996 (October 1, 1995?September 30, 1996). Optical backscatterance sensors and water samples were used to monitor suspended solids at three sites in Suisun Bay, three sites in Central San Francisco Bay, and three sites in South San Francisco Bay. Sensors were positioned at two depths at most sites. Water samples were collected periodically and were analyzed for concentrations of suspended solids. The results of the analyses were used to calibrate the electrical output of the optical backscatterance sensors. This report presents the data-collection methods used and summarizes the suspended-solids concentration data collected from October 1995 through September 1996. Calibration plots and plots of edited data for each sensor also are presented.

  13. Summary of suspended-solids concentration data, San Francisco Bay, California, water year 1998

    USGS Publications Warehouse

    Buchanan, Paul A.; Ruhl, Catherine A.

    2000-01-01

    Suspended-solids concentration data were collected in San Francisco Bay during water year 1998 (October 1, 1997?September 30, 1998). Optical backscatterance sensors and water samples were used to monitor suspended solids at two sites in Suisun Bay, three sites in Central San Francisco Bay, and three sites in South San Francisco Bay. Sensors were positioned at two depths at most sites. Water samples were collected periodically and were analyzed for concentrations of suspended solids. The results of the analyses were used to calibrate the electrical output of the optical backscatterance sensors. This report presents the data-collection methods used and summarizes the suspended-solids concentration data collected from October 1997 through September 1998. Calibration plots and plots of edited data for each sensor also are presented.

  14. Talc-bearing serpentinite and the creeping section of the San Andreas fault

    USGS Publications Warehouse

    Moore, Diane E.; Rymer, M.J.

    2007-01-01

    The section of the San Andreas fault located between Cholame Valley and San Juan Bautista in central California creeps at a rate as high as 28 mm yr -1 (ref. 1), and it is also the segment that yields the best evidence for being a weak fault embedded in a strong crust. Serpentinized ultramafic rocks have been associated with creeping faults in central and northern California, and serpentinite is commonly invoked as the cause of the creep and the low strength of this section of the San Andreas fault. However, the frictional strengths of serpentine minerals are too high to satisfy the limitations on fault strength, and these minerals also have the potential for unstable slip under some conditions. Here we report the discovery of talc in cuttings of serpentinite collected from the probable active trace of the San Andreas fault that was intersected during drilling of the San Andreas Fault Observatory at Depth (SAFOD) main hole in 2005. We infer that the talc is forming as a result of the reaction of serpentine minerals with silica-saturated hydrothermal fluids that migrate up the fault zone, and the talc commonly occurs in sheared serpentinite. This discovery is significant, as the frictional strength of talc at elevated temperatures is sufficiently low to meet the constraints on the shear strength of the fault, and its inherently stable sliding behaviour is consistent with fault creep. Talc may therefore provide the connection between serpentinite and creep in the San Andreas fault, if shear at depth can become localized along a talc-rich principal-slip surface within serpentinite entrained in the fault zone. ??2007 Nature Publishing Group.

  15. San Francisco and Bay Area, CA, USA

    NASA Technical Reports Server (NTRS)

    1991-01-01

    This cloud free color infrared view of San Francisco and Bay Area, CA (38.0N, 122.5W) is unusual because the city is normally concealed from view by clouds and fog. Gray tones represent urban areas and the red toned areas are vegetated. Within the city, parks easily stand out from the well-developed parts of the city as enclaves of color. The trace of the San Andreas fault shows as a straight valley running across the San Francisco peninsula.

  16. CIRSS vertical data integration, San Bernardino study

    NASA Technical Reports Server (NTRS)

    Hodson, W.; Christenson, J.; Michel, R. (Principal Investigator)

    1982-01-01

    The creation and use of a vertically integrated data base, including LANDSAT data, for local planning purposes in a portion of San Bernardino County, California are described. The project illustrates that a vertically integrated approach can benefit local users, can be used to identify and rectify discrepancies in various data sources, and that the LANDSAT component can be effectively used to identify change, perform initial capability/suitability modeling, update existing data, and refine existing data in a geographic information system. Local analyses were developed which produced data of value to planners in the San Bernardino County Planning Department and the San Bernardino National Forest staff.

  17. SANS studies of micellar and magnetic fluids

    SciTech Connect

    Hayter, J.B,

    1985-08-01

    Small-angle neutron scattering (SANS) has proved to be an excellent technique for the study of complex fluids. This article introduces SANS from the viewpoint of such studies. The use of SANS to determine the structures of concentrated micellar fluids is then discussed within the framework of current one-component macrofluid (OCM) models, and experimental examples are taken from several contemporary studies. Finally, the discussion is extended to magnetic fluids (ferrofluids) in which the neutron magnetic interaction plays an important experimental role. 25 refs., 11 figs., 1 tab.

  18. Does centennial morphodynamic evolution lead to higher channel efficiency in San Pablo Bay, California?

    USGS Publications Warehouse

    van der Wegen, M.; Jaffe, B.E.; Barnard, P.L.; Jaffee, B.E.; Schoellhamer, D.H.

    2013-01-01

    Measured bathymetries on 30 year interval over the past 150 years show that San Pablo Bay experienced periods of considerable deposition followed by periods of net erosion. However, the main channel in San Pablo Bay has continuously narrowed. The underlying mechanisms and consequences of this tidal channel evolution are not well understood. The central question of this study is whether tidal channels evolve towards a geometry that leads to more efficient hydraulic conveyance and sediment throughput. We applied a hydrodynamic process-based, numerical model (Delft3D), which was run on 5 San Pablo Bay bathymetries measured between 1856 and 1983. Model results shows increasing energy dissipation levels for lower water flows leading to an approximately 15% lower efficiency in 1983 compared to 1856. During the same period the relative seaward sediment throughput through the San Pablo Bay main channel increased by 10%. A probable explanation is that San Pablo Bay is still affected by the excessive historic sediment supply. Sea level rise and Delta surface water area variations over 150 years have limited effect on the model results. With expected lower sediment concentrations in the watershed and less impact of wind waves due to erosion of the shallow flats, it is possible that energy dissipations levels will decrease again in future decades. Our study suggests that the morphodynamic adaptation time scale to excessive variations in sediment supply to estuaries may be on the order of centuries.

  19. 22. Post Engineer Office, Presidio of San Francisco, Building # ...

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

    22. Post Engineer Office, Presidio of San Francisco, Building # 1049 Letterman General Hospital. Alterations to EKG Cardiology Clinic. November 1963. BUILDING 1049. - Presidio of San Francisco, Letterman General Hospital, Building No. 12, Letterman Hospital Complex, Edie Road, San Francisco, San Francisco County, CA

  20. 21. Post Engineer Office, Presidio of San Francisco, Letterman Army ...

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

    21. Post Engineer Office, Presidio of San Francisco, Letterman Army Hospital. EKG Cardiology Clinic, Building 1049. December 1955. BUILDING 1049. - Presidio of San Francisco, Letterman General Hospital, Building No. 12, Letterman Hospital Complex, Edie Road, San Francisco, San Francisco County, CA

  1. Presidio of San Francisco. Sheet 27. June 1945. SHOWING EASTERN ...

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

    Presidio of San Francisco. Sheet 27. June 1945. SHOWING EASTERN PORTION OF AREA B, BUILDINGS 901-919 AND WESTERN PORTION OF CRISSY FIELD - Presidio of San Francisco, Enlisted Men's Barracks Type, West end of Crissy Field, between Pearce & Maudlin Streets, San Francisco, San Francisco County, CA

  2. 42. Post Engineer Office, Presidio of San Francisco, Letterman Army ...

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

    42. Post Engineer Office, Presidio of San Francisco, Letterman Army Hospital, X-Ray Department and Second Floor Plan, X-Ray Department Plan, Building 1006. no date. BUILDING 1006. - Presidio of San Francisco, Letterman General Hospital, Building No. 27, Letterman Hospital Complex, Edie Road, San Francisco, San Francisco County, CA

  3. 1. ABANDONED TURNOUT (CALLED CAPTAIN WHEEL) TO SAN TAN INDIAN ...

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

    1. ABANDONED TURN-OUT (CALLED CAPTAIN WHEEL) TO SAN TAN INDIAN CANAL OFF OF SAN TAN FLOOD-WATER CANAL, T4S, R6E, S11/12. VIEW LOOKING SOUTHWEST. - San Carlos Irrigation Project, San Tan Indian Canal, North of Gila River, Coolidge, Pinal County, AZ

  4. 33 CFR 110.90 - San Diego Harbor, Calif.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false San Diego Harbor, Calif. 110.90... ANCHORAGE REGULATIONS Special Anchorage Areas § 110.90 San Diego Harbor, Calif. (a) Area A-1. In North San...) Area A-1a. In North San Diego Bay, the Shelter Island Roadstead Anchorage east of Shelter Island,...

  5. 33 CFR 110.90 - San Diego Harbor, Calif.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false San Diego Harbor, Calif. 110.90... ANCHORAGE REGULATIONS Special Anchorage Areas § 110.90 San Diego Harbor, Calif. (a) Area A-1. In North San...) Area A-1a. In North San Diego Bay, the Shelter Island Roadstead Anchorage east of Shelter Island,...

  6. 11. Photocopy of Painting (Original in De Young Museum, San ...

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

    11. Photocopy of Painting (Original in De Young Museum, San Francisco, Oriana Day Paintings 1861-1865) Photographer unknown, February 1940 PAINTING OF MISSION COMPLEX SHOWING EXTERIOR PRIOR TO 1835 - Mission San Miguel Arcangel, Highway 101, San Miguel, San Luis Obispo County, CA

  7. Vertical tectonic deformation associated with the San Andreas fault zone offshore of San Francisco, California

    USGS Publications Warehouse

    Ryan, H.F.; Parsons, T.; Sliter, R.W.

    2008-01-01

    A new fault map of the shelf offshore of San Francisco, California shows that faulting occurs as a distributed shear zone that involves many fault strands with the principal displacement taken up by the San Andreas fault and the eastern strand of the San Gregorio fault zone. Structures associated with the offshore faulting show compressive deformation near where the San Andreas fault goes offshore, but deformation becomes extensional several km to the north off of the Golden Gate. Our new fault map serves as the basis for a 3-D finite element model that shows that the block between the San Andreas and San Gregorio fault zone is subsiding at a long-term rate of about 0.2-0.3??mm/yr, with the maximum subsidence occurring northwest of the Golden Gate in the area of a mapped transtensional basin. Although the long-term rates of vertical displacement primarily show subsidence, the model of coseismic deformation associated with the 1906 San Francisco earthquake indicates that uplift on the order of 10-15??cm occurred in the block northeast of the San Andreas fault. Since 1906, 5-6??cm of regional subsidence has occurred in that block. One implication of our model is that the transfer of slip from the San Andreas fault to a fault 5??km to the east, the Golden Gate fault, is not required for the area offshore of San Francisco to be in extension. This has implications for both the deposition of thick Pliocene-Pleistocene sediments (the Merced Formation) observed east of the San Andreas fault, and the age of the Peninsula segment of the San Andreas fault.

  8. Vertical tectonic deformation associated with the San Andreas fault zone offshore of San Francisco, California

    NASA Astrophysics Data System (ADS)

    Ryan, H. F.; Parsons, T.; Sliter, R. W.

    2008-10-01

    A new fault map of the shelf offshore of San Francisco, California shows that faulting occurs as a distributed shear zone that involves many fault strands with the principal displacement taken up by the San Andreas fault and the eastern strand of the San Gregorio fault zone. Structures associated with the offshore faulting show compressive deformation near where the San Andreas fault goes offshore, but deformation becomes extensional several km to the north off of the Golden Gate. Our new fault map serves as the basis for a 3-D finite element model that shows that the block between the San Andreas and San Gregorio fault zone is subsiding at a long-term rate of about 0.2-0.3 mm/yr, with the maximum subsidence occurring northwest of the Golden Gate in the area of a mapped transtensional basin. Although the long-term rates of vertical displacement primarily show subsidence, the model of coseismic deformation associated with the 1906 San Francisco earthquake indicates that uplift on the order of 10-15 cm occurred in the block northeast of the San Andreas fault. Since 1906, 5-6 cm of regional subsidence has occurred in that block. One implication of our model is that the transfer of slip from the San Andreas fault to a fault 5 km to the east, the Golden Gate fault, is not required for the area offshore of San Francisco to be in extension. This has implications for both the deposition of thick Pliocene-Pleistocene sediments (the Merced Formation) observed east of the San Andreas fault, and the age of the Peninsula segment of the San Andreas fault.

  9. 76 FR 9709 - Water Quality Challenges in the San Francisco Bay/Sacramento-San Joaquin Delta Estuary

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-22

    ... chinook salmon and steelhead, that spend at least some of their life cycle in salt water. Usually, these... AGENCY 40 CFR Chapter I RIN-2009-ZA00 Water Quality Challenges in the San Francisco Bay/Sacramento-San... water quality conditions affecting aquatic resources in the San Francisco Bay/ Sacramento-San...

  10. 78 FR 13890 - Notice of Intent To Repatriate Cultural Items: San Francisco State University NAGPRA Program, San...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-01

    ... National Park Service Notice of Intent To Repatriate Cultural Items: San Francisco State University NAGPRA Program, San Francisco, CA AGENCY: National Park Service, Interior. ACTION: Notice. SUMMARY: The San... contact the San Francisco State University NAGPRA Program. DATES: Representatives of any Indian tribe...

  11. 33 CFR 165.1197 - Security Zones; San Francisco Bay, San Pablo Bay, Carquinez Strait, Suisun Bay, California.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Security Zones; San Francisco Bay, San Pablo Bay, Carquinez Strait, Suisun Bay, California. 165.1197 Section 165.1197 Navigation and... Areas Eleventh Coast Guard District § 165.1197 Security Zones; San Francisco Bay, San Pablo...

  12. 76 FR 10945 - San Luis Trust Bank, FSB, San Luis Obispo, CA; Notice of Appointment of Receiver

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-28

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE TREASURY Office of Thrift Supervision San Luis Trust Bank, FSB, San Luis Obispo, CA; Notice of Appointment of... Corporation as sole Receiver for San Luis Trust Bank, FSB, San Luis Obispo, California, (OTS No. 15051)...

  13. 33 CFR 165.1102 - Security Zone; Naval Base Point Loma; San Diego Bay, San Diego, CA.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    .... (b) Regulations. (1) The general regulations governing security zones found in 33 CFR 165.33 apply to... Loma; San Diego Bay, San Diego, CA. 165.1102 Section 165.1102 Navigation and Navigable Waters COAST... Guard District § 165.1102 Security Zone; Naval Base Point Loma; San Diego Bay, San Diego, CA....

  14. 33 CFR 165.1102 - Security Zone; Naval Base Point Loma; San Diego Bay, San Diego, CA.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    .... (b) Regulations. (1) The general regulations governing security zones found in 33 CFR 165.33 apply to... Loma; San Diego Bay, San Diego, CA. 165.1102 Section 165.1102 Navigation and Navigable Waters COAST... Guard District § 165.1102 Security Zone; Naval Base Point Loma; San Diego Bay, San Diego, CA....

  15. 77 FR 34984 - Notice of Intent To Repatriate a Cultural Item: San Diego Museum of Man, San Diego, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-12

    ... National Park Service Notice of Intent To Repatriate a Cultural Item: San Diego Museum of Man, San Diego, CA AGENCY: National Park Service, Interior. ACTION: Notice. SUMMARY: The San Diego Museum of Man, in... with the cultural item may contact the San Diego Museum of Man. DATES: Representatives of any...

  16. 75 FR 55270 - Safety Zone; NASSCO Launching of USNS Washington Chambers, San Diego Bay, San Diego, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-10

    ... Chambers, San Diego Bay, San Diego, CA AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a temporary safety zone on the navigable waters of the San Diego Bay in... the Port (COTP) San Diego or his designated representative. DATES: This rule is effective from 9:15...

  17. 33 CFR 165.1197 - Security Zones; San Francisco Bay, San Pablo Bay, Carquinez Strait, Suisun Bay, California.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Security Zones; San Francisco Bay, San Pablo Bay, Carquinez Strait, Suisun Bay, California. 165.1197 Section 165.1197 Navigation and... Areas Eleventh Coast Guard District § 165.1197 Security Zones; San Francisco Bay, San Pablo...

  18. 77 FR 15799 - Notice of Intent To Repatriate a Cultural Item: San Francisco State University, San Francisco, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-16

    ... National Park Service Notice of Intent To Repatriate a Cultural Item: San Francisco State University, San Francisco, CA AGENCY: National Park Service, Interior. ACTION: Notice. SUMMARY: The San Francisco State... affiliated with the cultural item may contact the San Francisco State University NAGPRA Program....

  19. Sediment conditions in the San Antonio River Basin downstream from San Antonio, Texas, 2000-13

    USGS Publications Warehouse

    Ockerman, Darwin J.; Banta, J. Ryan; Crow, Cassi L.; Opsahl, Stephen P.

    2015-01-01

    Sediment plays an important role in the ecological health of rivers and estuaries and consequently is an important issue for water-resource managers. To better understand sediment characteristics in the San Antonio River Basin, the U.S. Geological Survey, in cooperation with the San Antonio River Authority, completed a two-part study in the San Antonio River Basin downstream from San Antonio, Texas, to (1) collect and analyze sediment data to characterize sediment conditions and (2) develop and calibrate a watershed model to simulate hydrologic conditions and suspended-sediment loads during 2000–12.

  20. North elevation and second floor plan. San Bernardino Valley Union ...

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

    North elevation and second floor plan. San Bernardino Valley Union Junior College, Science Building. Includes physics, geology, and zoology departments shelving. Howard E. Jones, Architect, San Bernardino, California. Sheet 4, job no. 311. Scales 1/8 inch to the foot (elevations) and 1/2 inch to the foot (shelving). February 15, 1927. - San Bernardino Valley College, Life Science Building, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  1. 11. Office of the Post Engineer, Presidio of San Francisco. ...

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

    11. Office of the Post Engineer, Presidio of San Francisco. Location of Water Lines, Presidio of San Francisco. Sheet 31. November 1943. SHOWING EASTERN PORTION OF AREA A; BUILDINGS 274, 275, AND 277; AND POST ENGINEER'S SHOP AND YARDS INCLUDING BUILDINGS 280, 282-285, AND 288. - Presidio of San Francisco, Storehouse & Administration, Crissy Field North cantonment, Allen Street, San Francisco, San Francisco County, CA

  2. East and west elevations. San Berardino Valley Union Junior College, ...

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

    East and west elevations. San Berardino Valley Union Junior College, Science Building. Also includes elevations and sections of chemistry department shelving. Howard E. Jones, Architect, San Bernardino, California. Sheet 4, Job no. 311. Scales 1/8 inch to the foot (elevations) and 1/2 inch t other foot (shelving). February 15, 1927. - San Bernardino Valley College, Life Science Building, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  3. East and west elevations. San Berardino Valley Union Junior College, ...

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

    East and west elevations. San Berardino Valley Union Junior College, Library Building. Also includes miscellaneous full size details. Howard E. Jones, Architect, San Bernardino, California. Sheet 4, Job no. 315. Scales 1/8 inch to the foot (elevations). No date given on sheet (probably March or April, 1927). - San Bernardino Valley College, Library, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  4. Section AA through main entrance gates & west stairs. San ...

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

    Section AA through main entrance gates & west stairs. San Bernardino Valley Union Junior College, Science Building. Also includes plans and sections of boys' and girls' toilets. Howard E. Jones, Architect, San Bernardino, California. Sheet 5, job no. 311. Scales 1/4 inch to the foot (section AA) and 1/2 inch to the foot (toilet rooms). February 15, 1927. - San Bernardino Valley College, Life Science Building, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  5. Foundation plan. San Bernardino Valley Union Junior College, Library Building. ...

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

    Foundation plan. San Bernardino Valley Union Junior College, Library Building. Also includes sections A through MM. Howard E. Jones, Architect, San Bernardino, California. Sheet 1, job no. 315. Scales 1/8 inch to the foot (plan) and 1/2 inch to the foot (sections). No date given on sheet (probably March or April, 1927). - San Bernardino Valley College, Library, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  6. West elevation. San Bernardino Valley Union Junior College, Science Building. ...

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

    West elevation. San Bernardino Valley Union Junior College, Science Building. Also includes plan of entrance, section EE showing tiling and typical transom design, and a full size detail of a door jamb for inside concrete walls. Howard E. Jones, Architect, San Bernardino, California. Sheet 7, job no. 311. Scale 1.2 inch to the foot. February 15, 1927. - San Bernardino Valley College, Life Science Building, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  7. Foundation plan. San Bernardino Valley Union Junior College, Classics Building. ...

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

    Foundation plan. San Bernardino Valley Union Junior College, Classics Building. Also includes sections AA-KK (except DD). Howard E. Jones, Architect, San Bernardino, California. Sheet 1, job no. 312. Scales 1/8 inch to the foot (plan) and 1/2 inch to the foot (sections). February 15, 1927. - San Bernardino Valley College, Classics Building, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  8. Plot plan & miscellaneous details. San Bernardino Valley Union Junior ...

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

    Plot plan & miscellaneous details. San Bernardino Valley Union Junior College, Classics Building. Includes map drawers, surveying equipment lockers, counters, platforms, etc. Howard E. Jones, Architect, San Bernardino, California. Sheet 8, job no. 312. Scales 1/2 inch to the foot (details) and 1/64 inch to the foot (plot plan). February 15, 1927. - San Bernardino Valley College, Classics Building, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  9. Elevation and plan of east side entrance. San Bernardino Valley ...

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

    Elevation and plan of east side entrance. San Bernardino Valley Union Junior College, Library Building. Also includes sections II and SS of entrance hall; and a stress diagram of steel truss. Howard E. Jones, Architect, San Bernardino, California. Sheet 7, job no. 315. Scale 1/2 inch to the foot. No date given on sheet (probably March or April, 1927). - San Bernardino Valley College, Library, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  10. Computerized Bus Routing in San Francisco.

    ERIC Educational Resources Information Center

    Caswell, Peter J.; Jungherr, J. Anton

    1979-01-01

    A computerized routing and scheduling system for the San Francisco Public Schools includes the batch processing of bus route assignments and schedules for all schools and the online terminal processing of daily changes. (Author/MLF)

  11. Children and the San Fernando earthquake

    USGS Publications Warehouse

    Howard, S. J.

    1980-01-01

    Before dawn, on February 9, 1971, a magnitude 6.4 earthquake occurred in the San Fernando Valley of California. On the following day, theSan Fernando Valley Child Guidance Clinic, through radio and newspapers, offered mental health crises services to children frightened by the earthquake. Response to this invitation was immediate and almost overwhelming. During the first 2 weeks, the Clinic's staff counseled hundreds of children who were experiencing various degrees of anxiety. 

  12. Trouble Brewing in San Diego. Policy Brief

    ERIC Educational Resources Information Center

    Buck, Stuart

    2010-01-01

    The city of San Diego will face enormous budgetary pressures from the growing deficits in public pensions, both at a state and local level. In this policy brief, the author estimates that San Diego faces total of $45.4 billion, including $7.95 billion for the county pension system, $5.4 billion for the city pension system, and an estimated $30.7…

  13. Toxic phytoplankton in San Francisco Bay

    USGS Publications Warehouse

    Rodgers, Kristine M.; Garrison, David L.; Cloern, James E.

    1996-01-01

    The Regional Monitoring Program (RMP) was conceived and designed to document the changing distribution and effects of trace substances in San Francisco Bay, with focus on toxic contaminants that have become enriched by human inputs. However, coastal ecosystems like San Francisco Bay also have potential sources of naturally-produced toxic substances that can disrupt food webs and, under extreme circumstances, become threats to public health. The most prevalent source of natural toxins is from blooms of algal species that can synthesize metabolites that are toxic to invertebrates or vertebrates. Although San Francisco Bay is nutrient-rich, it has so far apparently been immune from the epidemic of harmful algal blooms in the world’s nutrient-enriched coastal waters. This absence of acute harmful blooms does not imply that San Francisco Bay has unique features that preclude toxic blooms. No sampling program has been implemented to document the occurrence of toxin-producing algae in San Francisco Bay, so it is difficult to judge the likelihood of such events in the future. This issue is directly relevant to the goals of RMP because harmful species of phytoplankton have the potential to disrupt ecosystem processes that support animal populations, cause severe illness or death in humans, and confound the outcomes of toxicity bioassays such as those included in the RMP. Our purpose here is to utilize existing data on the phytoplankton community of San Francisco Bay to provide a provisional statement about the occurrence, distribution, and potential threats of harmful algae in this Estuary.

  14. San Andreas fault geometry in the Parkfield, California, region

    USGS Publications Warehouse

    Simpson, R.W.; Barall, M.; Langbein, J.; Murray, J.R.; Rymer, M.J.

    2006-01-01

    In map view, aftershocks of the 2004 Parkfield earthquake lie along a line that forms a straighter connection between San Andreas fault segments north and south of the Parkfield reach than does the mapped trace of the fault itself. A straightedge laid on a geologic map of Central California reveals a ???50-km-long asymmetric northeastward warp in the Parkfield reach of the fault. The warp tapers gradually as it joins the straight, creeping segment of the San Andreas to the north-west, but bends abruptly across Cholame Valley at its southeast end to join the straight, locked segment that last ruptured in 1857. We speculate that the San Andreas fault surface near Parkfield has been deflected in its upper ???6 km by nonelastic behavior of upper crustal rock units. These units and the fault surface itself are warped during periods between large 1857-type earthquakes by the presence of the 1857-locked segment to the south, which buttresses intermittent coseismic and continuous aseismic slip on the Parkfield reach. Because of nonelastic behavior, the warping is not completely undone when an 1857-type event occurs, and the upper portion of the three-dimensional fault surface is slowly ratcheted into an increasingly prominent bulge. Ultimately, the fault surface probably becomes too deformed for strike-slip motion, and a new, more vertical connection to the Earth's surface takes over, perhaps along the Southwest Fracture Zone. When this happens a wedge of material currently west of the main trace will be stranded on the east side of the new main trace.

  15. 33 CFR 165.1187 - Security Zones; Golden Gate Bridge and the San Francisco-Oakland Bay Bridge, San Francisco Bay...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Bridge and the San Francisco-Oakland Bay Bridge, San Francisco Bay, California. 165.1187 Section 165.1187... San Francisco-Oakland Bay Bridge, San Francisco Bay, California. (a) Location. All waters extending... Golden Gate Bridge and the San Francisco-Oakland Bay Bridge, in San Francisco Bay, California....

  16. 33 CFR 165.1187 - Security Zones; Golden Gate Bridge and the San Francisco-Oakland Bay Bridge, San Francisco Bay...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Bridge and the San Francisco-Oakland Bay Bridge, San Francisco Bay, California. 165.1187 Section 165.1187... San Francisco-Oakland Bay Bridge, San Francisco Bay, California. (a) Location. All waters extending... Golden Gate Bridge and the San Francisco-Oakland Bay Bridge, in San Francisco Bay, California....

  17. Anthropogenic influences on shoreline and nearshore evolution in the San Francisco Bay coastal system

    USGS Publications Warehouse

    Dallas, K.L.; Barnard, P.L.

    2011-01-01

    Analysis of four historical bathymetric surveys over a 132-year period has revealed significant changes to the morphology of the San Francisco Bar, an ebb-tidal delta at the mouth of San Francisco Bay estuary. From 1873 to 2005 the San Francisco Bar vertically-eroded an average of 80 cm over a 125 km2 area, which equates to a total volume loss of 100 ± 52 million m3 of fine- to coarse-grained sand. Comparison of the surveys indicates the entire ebb-tidal delta contracted radially, with the crest moving landward an average of 1 km. Long-term erosion of the ebb-tidal delta is hypothesized to be due to a reduction in the tidal prism of San Francisco Bay and a decrease in coastal sediment supply, both as a result of anthropogenic activities. Prior research indicates that the tidal prism of the estuary was reduced by 9% from filling, diking, and sedimentation. Compilation of historical records dating back to 1900 reveals that a minimum of 200 million m3 of sediment has been permanently removed from the San Francisco Bay coastal system through dredging, aggregate mining, and borrow pit mining. Of this total, ~54 million m3 of sand-sized or coarser sediment was removed from central San Francisco Bay. With grain sizes comparable to the ebb-tidal delta, and its direct connection to the bay mouth, removal of sediments from central San Francisco Bay may limit the sand supply to the delta and open coast beaches. SWAN wave modeling illustrates that changes to the morphology of the San Francisco Bar have altered the alongshore wave energy distribution at adjacent Ocean Beach, and thus may be a significant factor in a persistent beach erosion ‘hot spot’ occurring in the area. Shoreline change analyses show that the sandy shoreline in the shadow of the ebb-tidal delta experienced long-term (1850s/1890s to 2002) and short-term (1960s/1980s to 2002) accretion while the adjacent sandy shoreline exposed to open-ocean waves experienced long-term and short-term erosion. Therefore

  18. Anthropogenic influences on shoreline and nearshore evolution in the San Francisco Bay coastal system

    NASA Astrophysics Data System (ADS)

    Dallas, Kate L.; Barnard, Patrick L.

    2011-03-01

    Analysis of four historical bathymetric surveys over a 132-year period has revealed significant changes to the morphology of the San Francisco Bar, an ebb-tidal delta at the mouth of San Francisco Bay estuary. From 1873 to 2005 the San Francisco Bar vertically-eroded an average of 80 cm over a 125 km 2 area, which equates to a total volume loss of 100 ± 52 million m 3 of fine- to coarse-grained sand. Comparison of the surveys indicates the entire ebb-tidal delta contracted radially, with the crest moving landward an average of 1 km. Long-term erosion of the ebb-tidal delta is hypothesized to be due to a reduction in the tidal prism of San Francisco Bay and a decrease in coastal sediment supply, both as a result of anthropogenic activities. Prior research indicates that the tidal prism of the estuary was reduced by 9% from filling, diking, and sedimentation. Compilation of historical records dating back to 1900 reveals that a minimum of 200 million m 3 of sediment has been permanently removed from the San Francisco Bay coastal system through dredging, aggregate mining, and borrow pit mining. Of this total, ˜54 million m 3 of sand-sized or coarser sediment was removed from central San Francisco Bay. With grain sizes comparable to the ebb-tidal delta, and its direct connection to the bay mouth, removal of sediments from central San Francisco Bay may limit the sand supply to the delta and open coast beaches. SWAN wave modeling illustrates that changes to the morphology of the San Francisco Bar have altered the alongshore wave energy distribution at adjacent Ocean Beach, and thus may be a significant factor in a persistent beach erosion 'hot spot' occurring in the area. Shoreline change analyses show that the sandy shoreline in the shadow of the ebb-tidal delta experienced long-term (1850s/1890s to 2002) and short-term (1960s/1980s to 2002) accretion while the adjacent sandy shoreline exposed to open-ocean waves experienced long-term and short-term erosion. Therefore

  19. Abrupt along-strike change in tectonic style: San Andreas Fault zone, San Francisco Peninsula

    NASA Astrophysics Data System (ADS)

    Zoback, Mary Lou; Jachens, Robert C.; Olson, Jean A.

    1999-05-01

    Seismicity and high-resolution aeromagnetic data are used to define an abrupt change from compressional to extensional tectonism within a 10- to 15-km-wide zone along the San Andreas fault on the San Francisco Peninsula and offshore from the Golden Gate. This 100-km-long section of the San Andreas fault includes the hypocenter of the Mw = 7.8 1906 San Francisco earthquake as well as the highest level of persistent microseismicity along that ˜470-km-long rupture. We define two distinct zones of deformation along this stretch of the fault using well-constrained relocations of all post-1969 earthquakes based a joint one-dimensional velocity/hypocenter inversion and a redetermination of focal mechanisms. The southern zone is characterized by thrust- and reverse-faulting focal mechanisms with NE trending P axes that indicate "fault-normal" compression in 7- to 10-km-wide zones of deformation on both sides of the San Andreas fault. A 1- to 2-km-wide vertical zone beneath the surface trace of the San Andreas is characterized by its almost complete lack of seismicity. The compressional deformation is consistent with the young, high topography of the Santa Cruz Mountains/Coast Ranges as the San Andreas fault makes a broad restraining left bend (˜10°) through the southernmost peninsula. A zone of seismic quiescence ˜15 km long separates this compressional zone to the south from a zone of combined normal-faulting and strike-slip-faulting focal mechanisms (including a ML = 5.3 earthquake in 1957) on the northernmost peninsula and offshore on the Golden Gate platform. Both linear pseudogravity gradients, calculated from the aeromagnetic data, and seismic reflection data indicate that the San Andreas fault makes an abrupt ˜3-km right step less than 5 km offshore in this northern zone. A similar right-stepping (dilatational) geometry is also observed for the subparallel San Gregorio fault offshore. Persistent seismicity and extensional tectonism occur within the San Andreas

  20. Abrupt along-strike change in tectonic style: San Andreas fault zone, San Francisco Peninsula

    USGS Publications Warehouse

    Zoback, M.L.; Jachens, R.C.; Olson, J.A.

    1999-01-01

    Seismicity and high-resolution aeromagnetic data are used to define an abrupt change from compressional to extensional tectonism within a 10- to 15-km-wide zone along the San Andreas fault on the San Francisco Peninsula and offshore from the Golden Gate. This 100-km-long section of the San Andreas fault includes the hypocenter of the Mw = 7.8 1906 San Francisco earthquake as well as the highest level of persistent microseismicity along that ???470-km-long rupture. We define two distinct zones of deformation along this stretch of the fault using well-constrained relocations of all post-1969 earthquakes based a joint one-dimensional velocity/hypocenter inversion and a redetermination of focal mechanisms. The southern zone is characterized by thrust- and reverse-faulting focal mechanisms with NE trending P axes that indicate "fault-normal" compression in 7- to 10-km-wide zones of deformation on both sides of the San Andreas fault. A 1- to 2-km-wide vertical zone beneath the surface trace of the San Andreas is characterized by its almost complete lack of seismicity. The compressional deformation is consistent with the young, high topography of the Santa Cruz Mountains/Coast Ranges as the San Andreas fault makes a broad restraining left bend (???10??) through the southernmost peninsula. A zone of seismic quiescence ???15 km long separates this compressional zone to the south from a zone of combined normal-faulting and strike-slip-faulting focal mechanisms (including a ML = 5.3 earthquake in 1957) on the northernmost peninsula and offshore on the Golden Gate platform. Both linear pseudo-gravity gradients, calculated from the aeromagnetic data, and seismic reflection data indicate that the San Andreas fault makes an abrupt ???3-km right step less than 5 km offshore in this northern zone. A similar right-stepping (dilatational) geometry is also observed for the subparallel San Gregorio fault offshore. Persistent seismicity and extensional tectonism occur within the San

  1. Commercial production of ethanol in the San Luis Valley, Colorado. Final Report

    SciTech Connect

    Hewlett, E.M.; Erickson, M.V.; Ferguson, C.D.; Sherwood, P.B.; Boswell, B.S.; Walter, K.M.; Hart, M.L.

    1983-07-01

    The purpose of this study is to assess the commercial feasibility of producing between 76 and 189 million liters (20 and 50 million gallons) of ethanol annually in the San Luis Valley, Colorado using geothermal energy as the primary heat source. The San Luis Valley is located in south-central Colorado. The valley is a high basin situated approximately 2316 meters (7600 feet) above sea level which contains numerous warm water wells and springs. A known geothermal resource area (KGRA) is located in the east-central area of the valley. The main industry in the valley is agriculture, while the main industry in the surrounding mountains is lumber. Both of these industries can provide feedstock for the production of ethanol.

  2. Commercial production of ethanol in the San Luis Valley, Colorado. Final report

    SciTech Connect

    Hewlett, E.M.; Erickson, M.V.; Ferguson, C.D.; Boswell, B.S.; Walter, K.M.; Hart, M.L.; Sherwood, P.B.

    1983-07-01

    The commercial feasibility of producing between 76 and 189 million liters (20 to 50 million gallons) of ethanol annually in the San Luis Valley, Colorado using geothermal energy as the primary heat source was assessed. The San Luis Valley is located in south-central Colorado. The valley is a high basin situated approximately 2316 meters (7600 feet) above sea level which contains numerous warm water wells and springs. A known geothermal resource area (IGRA) is located in the east-central area of the valley. The main industry in the valley is agriculture, while the main industry in the surrounding mountains is lumber. Both of these industries can provide feedstocks for the production of ethanol.

  3. Geologic maps of the Sacramento-San Joaquin Delta, California

    USGS Publications Warehouse

    Atwater, Brian F.

    1982-01-01

    The Sacramento-San Joaquin Delta, the arm of the San Francisco Bay estuary that reaches into the Central Valley of California, differs from typical coastal-plain deltas in three important respects.  First, rather than meeting the ocean individually and directly, all major waterways of this delta discharge via a single constricted outlet into a chain of estuarine bays and straits.  Second, in the most common vertical sequence of deposits, peat and mud deposited in tidal marshes and swamps (tidal wetlands) directly overlie alluvium or eolian sand, a sequence recording a landward spread of tidal environments rather than the seaward migration of fluvial environments that is typical of coastal-plain deltas (Cosby, 1941, p. 43; Thompson, 1957, p. 12; Shlemon and Begg, 1975, p. 259; Atwater and Belknap, 1980).  Finally, intensive human use has led to a peculiar set of conflicts involving rights to water and responsibilities for flood-control levees (Kockelman and other, 1982).

  4. Sans Spring Field Exploration Model, Nye County, Nevada

    SciTech Connect

    Mitchell, M.H.

    1995-06-01

    The existing model for Oligocene volcanic reservoir production in Railroad Valley was expanded with the discovery of oil at Sans Spring field by CENEX, et. al in March, 1993. Prior to drilling the CENEX No. 5-14 Federal (SWNW, section 14, T7N-R56E), economic production had only been established along the east and west borders of the valley, in structures associated with large offset normal faults. The location of Sans Spring field is on an east-west structural high that separates the productive central Railroad Valley sub-basin from the as yet unproductive southern sub-basin. Gravity, regional and detailed conventional 2-D seismic data coverage was employed to define the structure. This geophysical data further suggested that the structure had remained relatively undeformed, providing seal and trap integrity, during the post Oligocene extensional structural development of Railroad Valley. The location also met a critical criterion of being along a potential hydrocarbon migration pathway for oil generated by the Mississippian Chainman shale source rocks. The discovery well found reservoir development in a moderately welded and altered rhyolitic ignimbrite, with an IPF 1253 BOPD. The trap is an angular unconformity, with truncation to the west that has been modified and complicated by cut and fill channeling and faulting. Definition of the structural configuration, fault geometries and offsets has been greatly enhanced with the acquisition of a 3-D seismic survey. However, the data volume does not as yet provide an unambiguous solution to stratigraphic variations.

  5. San Mateo County's Server Information Program (S.I.P.): A Community-Based Alcohol Server Training Program.

    ERIC Educational Resources Information Center

    de Miranda, John

    The field of alcohol server awareness and training has grown dramatically in the past several years and the idea of training servers to reduce alcohol problems has become a central fixture in the current alcohol policy debate. The San Mateo County, California Server Information Program (SIP) is a community-based prevention strategy designed to…

  6. San Diego's Big Boom: District Bureaucracy Supports Culture of Learning. A Research Report. Document R-02-2

    ERIC Educational Resources Information Center

    Hightower, Amy M.

    2002-01-01

    This paper contributes to an emerging body of literature on school districts as active partners in education reform. Using qualitative methods, it details the first three years of a major districtwide initiative in San Diego City Schools as reformers sought to orient central office bureaucracy around an instructional agenda. This paper both…

  7. Assessment of Goods and Valuation of Ecosystem Services (AGAVES), San Pedro River Basin, U.S./Mexico

    EPA Science Inventory

    A consortium of federal, academic, and non-government organizations (NGO) partners have established a collaborative research enterprise in the San Pedro River Basin to develop methods, standards, and tools to assess and value ecosystem goods and services. The central premise of e...

  8. Una Visita al Viejo San Juan (A Visit to Old San Juan).

    ERIC Educational Resources Information Center

    Cabello, Victor; And Others

    Written in Spanish, this black and white illustrated booklet provides a tour of Old San Juan, Puerto Rico's oldest and most historic city. Brief historical information is provided on the Perro de San Jeronimo, a statue of a barking dog found in front of the Castillo; Plaza de Colon, a small plaza dedicated to Christopher Columbus; the Catedral de…

  9. 33 CFR 165.754 - Safety Zone: San Juan Harbor, San Juan, PR.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... following area: (1) The waters around Liquefied Petroleum Gas ships entering San Juan Harbor in an area one... referenced use datum: NAD 83. (2) The waters around Liquefied Petroleum Gas ships departing San Juan Harbor... Petroleum Gas vessels via a marine broadcast Notice to Mariners. (5) Should the actual time of entry of...

  10. 33 CFR 165.754 - Safety Zone: San Juan Harbor, San Juan, PR.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... following area: (1) The waters around Liquefied Petroleum Gas ships entering San Juan Harbor in an area one... referenced use datum: NAD 83. (2) The waters around Liquefied Petroleum Gas ships departing San Juan Harbor... Petroleum Gas vessels via a marine broadcast Notice to Mariners. (5) Should the actual time of entry of...

  11. 77 FR 60899 - Safety Zone; Sea World San Diego Fireworks, Mission Bay; San Diego, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-05

    ... DHS Department of Homeland Security FR Federal Register NPRM Notice of Proposed Rulemaking A... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Sea World San Diego Fireworks, Mission Bay... establishing a safety zone on the navigable waters of Mission Bay in support of the Sea World San...

  12. 78 FR 29025 - Sea World San Diego Fireworks 2013 Season; Mission Bay, San Diego, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-17

    ... FR Federal Register NPRM Notice of Proposed Rulemaking A. Regulatory History and Information The... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Sea World San Diego Fireworks 2013 Season; Mission Bay... establishing a safety zone on the navigable waters of Mission Bay in support of the Sea World San...

  13. 77 FR 42638 - Safety Zone: Sea World San Diego Fireworks, Mission Bay; San Diego, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-20

    .... SUPPLEMENTARY INFORMATION: Table of Acronyms DHS Department of Homeland Security FR Federal Register NPRM Notice... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone: Sea World San Diego Fireworks, Mission Bay... establishing a safety zone on the navigable waters of Mission Bay in support of the Sea World San...

  14. 78 FR 39610 - Safety Zone; Big Bay Boom, San Diego Bay; San Diego, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-02

    ... Security FR Federal Register NPRM Notice of Proposed Rulemaking A. Regulatory History and Information The...) on May 20, 2013 (78 FR 29289). The Coast Guard received no comments on that NPRM and as such, no... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Big Bay Boom, San Diego Bay; San Diego,...

  15. 78 FR 42027 - Safety Zone; San Diego Bayfair; Mission Bay, San Diego, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-15

    .... SUPPLEMENTARY INFORMATION: Table of Acronyms DHS Department of Homeland Security FR Federal Register NPRM Notice... 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; San Diego Bayfair; Mission Bay, San...

  16. 78 FR 53245 - Safety Zone; San Diego Bayfair; Mission Bay, San Diego, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-29

    ... Department of Homeland Security FR Federal Register NPRM Notice of Proposed Rulemaking A. Regulatory History... Proposed Rulemaking (NPRM) on July 15, 2013 (78 FR 42027). The Coast Guard received no comments on the NPRM... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; San Diego Bayfair; Mission Bay, San...

  17. 77 FR 70891 - Safety Zone; Bay Bridge Construction, San Francisco Bay, San Francisco, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-28

    ...: Table of Acronyms DHS Department of Homeland Security FR Federal Register NPRM Notice of Proposed... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Bay Bridge Construction, San Francisco Bay, San Francisco, CA AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard...

  18. 76 FR 1386 - Safety Zone; Centennial of Naval Aviation Kickoff, San Diego Bay, San Diego, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-10

    ... Federal Register (73 FR 3316). 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; Centennial of Naval Aviation Kickoff, San Diego Bay, San Diego, CA AGENCY: Coast Guard, DHS. ACTION: Notice of proposed rulemaking. SUMMARY:...

  19. 78 FR 29289 - Safety Zone; Big Bay Boom, San Diego Bay, San Diego, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-20

    ... Department of Homeland Security FR Federal Register NPRM Notice of Proposed Rulemaking A. Public... Act notice regarding our public dockets in the January 17, 2008, issue of the Federal Register (73 FR... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Big Bay Boom, San Diego Bay, San Diego,...

  20. 78 FR 38584 - Safety Zone; San Diego Symphony Summer POPS Fireworks 2013 Season, San Diego, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-27

    ... FR Federal Register NPRM Notice of Proposed Rulemaking A. Regulatory History and Information The... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; San Diego Symphony Summer POPS Fireworks 2013 Season, San Diego, CA AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The...

  1. 78 FR 10062 - Safety Zone; Sea World San Diego Fireworks, Mission Bay; San Diego, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-13

    ... Acronyms DHS Department of Homeland Security FR Federal Register NPRM Notice of Proposed Rulemaking A... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Sea World San Diego Fireworks, Mission Bay; San Diego, CA AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard...

  2. The San Andreas Fault 'Supersite' (Invited)

    NASA Astrophysics Data System (ADS)

    Hudnut, K. W.

    2013-12-01

    An expanded and permanent Supersite has been proposed to the Committee on Earth Observation Satellites (CEOS) for the San Andreas Fault system, based upon the successful initial Group on Earth Observations (GEO) Geohazard Supersite for the Los Angeles region from 2009-2013. As justification for the comprehensive San Andreas Supersite, consider the earthquake history of California, in particular the devastating M 7.8 San Francisco earthquake of 1906, which occurred along the San Andreas Fault, as did an earthquake of similar magnitude in 1857 in southern California. Los Angeles was only a small town then, but now the risk exposure has increased for both of California's megacities. Between the San Francisco and Los Angeles urban areas lies a section of the San Andreas Fault known to creep continually, so it has relatively less earthquake hazard. It used to be thought of as capable of stopping earthquakes entering it from either direction. Transitional behavior at either end of the creeping section is known to display a full range of seismic to aseismic slip events and accompanying seismicity and strain transient events. Because the occurrence of creep events is well documented by instrumental networks such as CISN and PBO, the San Andreas Supersite can be expected to be especially effective. A good baseline level of geodetic data regarding past events and strain accumulation and release exists. Many prior publications regarding the occurrence of geophysical phenomena along the San Andreas Fault system mean that in order to make novel contributions, state-of-the-art science will be required within this Supersite region. In more recent years, the 1989 Loma Prieta earthquake struck adjacent to the San Andreas Fault and caused the most damage along the western side of the San Francisco Bay Area. More recently, the concern has focused on the potential for future events along the Hayward Fault along the eastern side of San Francisco Bay. In Southern California, earthquakes

  3. 78 FR 19103 - Safety Zone; Spanish Navy School Ship San Sebastian El Cano Escort; Bahia de San Juan; San Juan, PR

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-29

    ... Acronyms DHS Department of Homeland Security FR Federal Register NPRM Notice of Proposed Rulemaking A... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Spanish Navy School Ship San Sebastian El Cano Escort; Bahia de San Juan; San Juan, PR AGENCY: Coast Guard, DHS. ACTION: Temporary final...

  4. Assessment of remaining recoverable oil in selected major oil fields of the San Joaquin Basin, California

    USGS Publications Warehouse

    Tennyson, Marilyn E.; Cook, Troy A.; Charpentier, Ronald R.; Gautier, Donald L.; Klett, Timothy R.; Verma, Mahendra K.; Ryder, Robert T.; Attanasi, E.D.; Freeman, P.A.; Le, Phoung A.

    2012-01-01

    The U.S. Geological Survey (USGS) recently completed an estimate of volumes of technically recoverable, conventional oil that could eventually be added to reserves in nine selected major oil fields in the San Joaquin Basin in central California. The mean total volume of potential oil reserves that might be added in the nine fields using improved oil-recovery technologies was estimated to be about 6.5 billion barrels of oil.

  5. Geologic and hydrologic characterization of coalbed-methane reservoirs in the San Juan basin

    SciTech Connect

    Kaiser, W.R. ); Ayers, W.B. Jr.

    1994-09-01

    Fruitland coals are best developed in the north-central part of the San Juan basin. Coal distribution is controlled by shoreline and fluvial depositional settings. Hydraulic gradient, pressure regime, and hydrochemistry reflect regional permeability contrasts. The most productive (>1 MMcf/D) coalbed wells occur along a structural hinge line in association with a regional permeability barrier (no-flow boundary) at the basin center.

  6. California coastal processes study: Skylab. [San Pablo and San Francisco Bays

    NASA Technical Reports Server (NTRS)

    Pirie, D. M.; Steller, D. D. (Principal Investigator)

    1975-01-01

    The author has identified the following significant results. In San Pablo Bay, the patterns of dredged sediment discharges were plotted over a three month period. It was found that lithogenous particles, kept in suspension by the fresh water from the Sacramento-San Joaquin, were transported downstream to the estuarine area at varying rates depending on the river discharge level. Skylab collected California coastal imagery at limited times and not at constant intervals. Resolution, however, helped compensate for lack of coverage. Increased spatial and spectral resolution provided details not possible utilizing Landsat imagery. The S-192 data was reformatted; band by band image density stretching was utilized to enhance sediment discharge patterns entrainment, boundaries, and eddys. The 26 January 1974 Skylab 4 imagery of San Francisco Bay was taken during an exceptionally high fresh water and suspended sediment discharge period. A three pronged surface sediment pattern was visible where the Sacramento-San Joaquin Rivers entered San Pablo Bay through Carquinez Strait.

  7. Thermal regime of the San Andreas fault near Parkfield, California

    USGS Publications Warehouse

    Sass, J.H.; Williams, C.F.; Lachenbruch, A.H.; Galanis, S.P.; Grubb, F.V.

    1997-01-01

    Knowledge of the temperature variation with depth near the San Andreas fault is vital to understanding the physical processes that occur within the fault zone during earthquakes and creep events. Parkfield is near the southern end of the Coast Ranges segment of the San Andreas fault. This segment has higher mean heat flow than the Cape Mendocino segment to the northwest or the Mojave segment to the southeast. Boreholes were drilled specifically for the U.S. Geological Survey's Parkfield earthquake prediction experiment or converted from other uses at 25 sites within a few kilometers of the fault near Parkfield. These holes, which range in depth from 150 to over 1500 m, were intended mainly for the deployment of volumetric strain meters, water-level recorders, and other downhole instruments. Temperature profiles were obtained from all the holes, and heat flow values were estimated from 17 of them. For a number of reasons, including a paucity of thermal conductivity data and rugged local topography, the accuracy of individual determinations was not sufficiently high to document local variations in heat flow. Values range from 54 to 92 mW m-2, with mean and 95% confidence limits of 74 ?? 4 mW m-2. This mean is slightly lower than the mean (83 ?? 3) of 39 previously published values from the central Coast Ranges, but it is consistent with the overall pattern of elevated heat flow in the Coast Ranges, and it is transitional to the mean of 68 ?? 2 mW m-2 that characterizes the Mojave segment of the San Andreas fault immediately to the south. The lack of a heat flow peak near the fault underscores the absence of a frictional thermal anomaly and provides additional support for a very small resolved shear stress parallel to the San Andreas fault and the nearly fault-normal maximum compressive stress observed in this region. Estimates of subsurface thermal conditions indicate that the seismic-aseismic transition for the Parkfield segment corresponds to temperatures in the

  8. Central line infections - hospitals

    MedlinePlus

    ... infection; CVC - infection; Central venous device - infection; Infection control - central line infection; Nosocomial infection - central line infection; Hospital acquired infection - central line infection; Patient safety - central ...

  9. Historical Seismicity in the South San Francisco Bay Region

    USGS Publications Warehouse

    Bakun, William H.

    2008-01-01

    Locations (intensity centers) and moment magnitude M for 24 earthquakes (1858-1911) in the southern San Francisco Bay area are estimated from Modified Mercalli intensity (MMI) assignments. The uncertainties in location and M are generally large because there are few MMI assignments available. Preferred locations are selected to be consistent with a simple model for seismic activity on the central and southern Calaveras fault. Significant seismic activity can be explained by repetitive failure of the same fault areas in nearly identical earthquakes. Significant earthquake activity occurred on both east- and west-Bay faults in the ten or so years before the 1868 east-Bay earthquake and before the1906 and 1989 west-Bay earthquakes.

  10. Late Glacial and Holocene Record of Hydroclimate in the San Luis Valley, Southern Colorado, USA

    NASA Astrophysics Data System (ADS)

    Yuan, F.; Koran, M.

    2012-12-01

    Lake sediments from the San Luis Valley, south-central Colorado, archive a detailed record of Late Glacial and Holocene climatic fluctuations in the southern Rocky Mountains. Together with radiometric dating analysis, measurements of grain size, magnetic susceptibility, total inorganic carbon (TIC), oxygen and carbon isotopic composition of the TIC fraction on sediment samples from San Luis Lake (at an average resolution of 60 years per sample) allow us to generate a sediment record of climatic change in the region spanning the last 16ka (1 ka=1000 cal yrs). This record documents the timing and duration of major climate episodes and trends, comparable to the existing paleoclimate records from the American Southwest. The Late Glacial record of San Luis Lake contains a big wet episode in the late part of the Mystery Interval (MI), a relatively dry climate during Bølling-Allerød (B/A) warm interval, and a relatively wet episode during the Younger Dryas (YD) interval, similar to the lake-level record found in the Estancia basin in central New Mexico. The early to middle Holocene record of d18O in the San Luis Lake parallels the calcite d18O record of Bison Lake in northern Colorado, documenting a history of significant change in precipitation seasonality across the northern boundary of the North American monsoon (NAM). The middle Holocene epoch is characterized by greater variations in magnetic susceptibility, d18O and d13C, suggesting the prevalence of wet, variable or transitional climate conditions. In contrast, the late Holocene climate is relatively dry, as indicated by more positive values of d18O in San Luis Lake. The results of this study reveal a complex history of climate evolution due to the interactions of two seasonally distinct precipitation regimes with mountainous landforms in the region.

  11. 33 CFR 165.1192 - Security Zones; Waters surrounding San Francisco International Airport and Oakland International...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... surrounding San Francisco International Airport and Oakland International Airport, San Francisco Bay... Security Zones; Waters surrounding San Francisco International Airport and Oakland International Airport, San Francisco Bay, California. (a) Locations. The following areas are security zones: (1)...

  12. 33 CFR 165.1192 - Security Zones; Waters surrounding San Francisco International Airport and Oakland International...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... surrounding San Francisco International Airport and Oakland International Airport, San Francisco Bay... Security Zones; Waters surrounding San Francisco International Airport and Oakland International Airport, San Francisco Bay, California. (a) Locations. The following areas are security zones: (1)...

  13. 3. Historic American Buildings Survey deYoung Museum, San Francisco MISSION ...

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

    3. Historic American Buildings Survey deYoung Museum, San Francisco MISSION BEFORE 1835 (ORIANA DAY PAINTINGS - (1861 - 1885) - Mission San Francisco de Asis, Mission & Sixteenth Streets, San Francisco, San Francisco County, CA

  14. SAAF: SANS data Analysis using Analytical Functions

    SciTech Connect

    Zhao, Jinkui

    2011-01-01

    The recently completed Extended Q-Range Small Angle Scattering Diffractometer (EQ-SANS) has put the focus on its software needs with renewed urgency. In a series of efforts, we aim at providing a complete set of software solutions on the EQ-SANS instrument. These programs include initial data processing, data correction and reduction, analytical model fitting to the scattering data, Monte Carlo simulation for structure determination, and virtual instrument simulation for experiment planning. SAAF is one such program for analytical data modeling. It takes the reduced EQ-SANS data and allows users to fit the data to analytical models. These models are easy to write. They can either be user written, or from the pre-supplied model library.

  15. Cacao use and the San Lorenzo Olmec.

    PubMed

    Powis, Terry G; Cyphers, Ann; Gaikwad, Nilesh W; Grivetti, Louis; Cheong, Kong

    2011-05-24

    Mesoamerican peoples had a long history of cacao use--spanning more than 34 centuries--as confirmed by previous identification of cacao residues on archaeological pottery from Paso de la Amada on the Pacific Coast and the Olmec site of El Manatí on the Gulf Coast. Until now, comparable evidence from San Lorenzo, the premier Olmec capital, was lacking. The present study of theobromine residues confirms the continuous presence and use of cacao products at San Lorenzo between 1800 and 1000 BCE, and documents assorted vessels forms used in its preparation and consumption. One elite context reveals cacao use as part of a mortuary ritual for sacrificial victims, an event that occurred during the height of San Lorenzo's power.

  16. Cacao use and the San Lorenzo Olmec

    PubMed Central

    Powis, Terry G.; Cyphers, Ann; Gaikwad, Nilesh W.; Grivetti, Louis; Cheong, Kong

    2011-01-01

    Mesoamerican peoples had a long history of cacao use—spanning more than 34 centuries—as confirmed by previous identification of cacao residues on archaeological pottery from Paso de la Amada on the Pacific Coast and the Olmec site of El Manatí on the Gulf Coast. Until now, comparable evidence from San Lorenzo, the premier Olmec capital, was lacking. The present study of theobromine residues confirms the continuous presence and use of cacao products at San Lorenzo between 1800 and 1000 BCE, and documents assorted vessels forms used in its preparation and consumption. One elite context reveals cacao use as part of a mortuary ritual for sacrificial victims, an event that occurred during the height of San Lorenzo's power. PMID:21555564

  17. Salt Ponds, South San Francisco Bay

    NASA Technical Reports Server (NTRS)

    2002-01-01

    higher resolution 1000 pixel-wide image The red and green colors of the salt ponds in South San Francisco Bay are brilliant visual markers for astronauts. The STS-111 crew photographed the bay south of the San Mateo bridge in June, 2002. This photograph is timely because a large number of the salt ponds (more than 16,500 acres) that are owned by Cargill, Inc. will be sold in September for wetlands restoration-a restoration project second in size only to the Florida Everglades project. Rough boundaries of the areas to be restored are outlined on the image. Over the past century, more than 80% of San Francisco Bay's wetlands have been filled and developed or diked off for salt mining. San Francisco Bay has supported salt mining since 1854. Cargill has operated most of the bay's commercial salt ponds since 1978, and had already sold thousands of acres to the State of California and the Don Edwards National Wildlife Refuge. This new transaction will increase San Francisco Bay's existing tidal wetlands by 50%. The new wetlands, to be managed by the California Department of Fish and Game and the U.S. Fish and Wildlife Service, will join the Don Edwards National Wildlife Refuge, and provide valuable habitat for birds, fish and other wildlife. The wetlands will contribute to better water quality and flood control in the bay, and open up more coastline for public enjoyment. Additional information: Cargill Salt Ponds (PDF) Turning Salt Into Environmental Gold Salt Ponds on Way to Becoming Wetlands Historic Agreement Reached to Purchase San Francisco Bay Salt Ponds Astronaut photograph STS111-376-3 was provided by the Earth Sciences and Image Analysis Laboratory at Johnson Space Center. Additional images taken by astronauts and cosmonauts can be viewed at the NASA-JSC Gateway to Astronaut Photography of Earth

  18. A Case for Historic Joint Rupture of the San Andreas and San Jacinto Faults

    NASA Astrophysics Data System (ADS)

    Lozos, J.

    2015-12-01

    The ~M7.5 southern California earthquake of 8 December 1812 ruptured the San Andreas Fault from Cajon Pass to at least as far north as Pallet Creek (Biasi et al., 2002). The 1812 rupture has also been identified in trenches at Burro Flats to the south (Yule and Howland, 2001). However, the lack of a record of 1812 at Plunge Creek, between Cajon Pass and Burro Flats (McGill et al., 2002), complicates the interpretation of this event as a straightforward San Andreas rupture. Paleoseismic records of a large early 19th century rupture on the northern San Jacinto Fault (Onderdonk et al., 2013; Kendrick and Fumal, 2005) allow for alternate interpretations of the 1812 earthquake. I use dynamic rupture modeling on the San Andreas-San Jacinto junction to determine which rupture behaviors produce slip patterns consistent with observations of the 1812 event. My models implement realistic fault geometry, a realistic velocity structure, and stress orientations based on seismicity literature. Under these simple assumptions, joint rupture of the two faults is the most common behavior. My modeling rules out a San Andreas-only rupture that is consistent with the data from the 1812 earthquake, and also shows that single fault events are unable to match the average slip per event for either fault. The choice of nucleation point affects the details of rupture directivity and slip distribution, but not the first order result that multi-fault rupture is the preferred behavior. While it cannot be definitively said that joint San Andreas-San Jacinto rupture occurred in 1812, these results are consistent with paleoseismic and historic data. This has implications for the possibility of future multi-fault rupture within the San Andreas system, as well as for interpretation of other paleoseismic events in regions of complex fault interactions.

  19. Multi-scale InSAR analysis of aseismic creep across the San Andreas, Calevaras,and Hayward Fault systems

    NASA Astrophysics Data System (ADS)

    Agram, P. S.; Simons, M.

    2011-12-01

    We apply the Multi-scale Interferometric Time-series (MInTS) technique, developed at Caltech,to study spatial variations in aseismic creep across the San Andreas, Calaveras and Hayward Faultsystems in Central California.Interferometric Synthetic Aperture Radar (InSAR) Time-series methods estimate the spatio-temporal evolution of surface deformation using multiple SAR interferograms. Traditional time-series analysis techniques like persistent scatterers and short baseline methods assume the statistical independence of InSAR phase measurements over space and time when estimating deformation. However, existing atmospheric phase screen models clearly show that noise in InSAR phase observations is correlated over the spatial domain. MInTS is an approach designed to exploit the correlation of phase observations over space to significantly improve the signal-to-noise ratio in the estimated deformation time-series compared to the traditional time-series InSAR techniques. The MInTS technique reduces the set of InSAR observations to a set of almost uncorrelated observations at various spatial scales using wavelets. Traditional inversion techniques can then be applied to the wavelet coefficients more effectively. Creep across the Central San Andreas Fault and the Hayward Fault has been studied previously using C-band (6 cm wavelength) ERS data, but detailed analysis of the transition zone between the San Andreas and Hayward Faults was not possible due to severe decorrelation. Improved coherence at L-band (24 cm wavelength) significantly improves the spatial coverage of the estimated deformation signal in our ALOS PALSAR data set. We analyze 450 ALOS PALSAR interferograms processed using 175 SAR images acquired between Dec 2006 and Dec 2010 that cover the area along the San Andreas Fault System from Richmond in the San Francisco Bay Area to Maricopa in the San Joaquin Valley.We invert the InSAR phase observations to estimate the constant Line-of-Sight (LOS) deformation

  20. 17. View of Park Avenue to north across the San ...

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

    17. View of Park Avenue to north across the San Francisco River. AZ-195 (Arizona Copper Company Manager's House) at right - Clifton Townsite, Confluence of Chase Creek & San Francisco River, Clifton, Greenlee County, AZ

  1. 98. Street view, East San Antonio Ave., looking west northwest, ...

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

    98. Street view, East San Antonio Ave., looking west northwest, Guarantee Shoe Co. is 211 East San Antonio Ave. - South El Paso Street Historic District, South El Paso, South Oregon & South Santa Fe Streets, El Paso, El Paso County, TX

  2. 7. Historic American Buildings Survey From Golden Gate Park San ...

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

    7. Historic American Buildings Survey From Golden Gate Park San Francisco, California Original: Ante 1860 Re-photo: February 1940 VIEW FROM SOUTH - Mission San Carlos Borromeo, Rio Road & Lausen Drive, Carmel-by-the-Sea, Monterey County, CA

  3. 6. Photocopy of painting (from California Historical Society, San Francisco, ...

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

    6. Photocopy of painting (from California Historical Society, San Francisco, California, Oriana Day, artist, 1879) EXTERIOR, VIEW FROM AN ANGLE OF MISSION AND SURROUNDING STRUCTURES - Mission San Francisco Solano de Sonoma, First & Spain Streets, Sonoma, Sonoma County, CA

  4. 1. Historic American Buildings Survey From the Collection: San Mateo ...

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

    1. Historic American Buildings Survey From the Collection: San Mateo Co. Historical Society Painting - 1865? 1885? Photocopy - August 1958 VIEW FROM NORTHWEST - Francisco Sanchez Adobe, Linda Mar Boulevard & Adobe Drive, Pacifica, San Mateo County, CA

  5. 5. Photocopy of painting (from De Young Museum, San Francisco, ...

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

    5. Photocopy of painting (from De Young Museum, San Francisco, California, Oriana Day, artist, c. 1861-1885) EXTERIOR VIEW OF MISSION BEFORE 1835 - Mission San Francisco Solano de Sonoma, First & Spain Streets, Sonoma, Sonoma County, CA

  6. Summary of suspended-sediment concentration data, San Francisco Bay, California, water year 2010

    USGS Publications Warehouse

    Buchanan, Paul A.; Morgan, Tara L.

    2014-01-01

    Suspended-sediment concentration data were collected by the U.S. Geological Survey in San Francisco Bay during water year 2010 (October 1, 2009–September 30, 2010). Turbidity sensors and water samples were used to monitor suspended-sediment concentration at two sites in Suisun Bay, one site in San Pablo Bay, three sites in Central San Francisco Bay, and one site in South San Francisco Bay. Sensors were positioned at two depths at most sites to help define the vertical variability of suspended sediments. Water samples were collected periodically and analyzed for concentrations of suspended sediment. The results of the analyses were used to calibrate the output of the turbidity sensors so that a record of suspended-sediment concentrations could be computed. This report presents the data-collection methods used and summarizes, in graphs, the suspended-sediment concentration data collected from October 2009 through September 2010. Calibration curves and plots of the processed data for each sensor also are presented.

  7. Summary of suspended-sediment concentration data, San Francisco Bay, California, water year 2009

    USGS Publications Warehouse

    Buchanan, Paul A.; Morgan, Tara L.

    2012-01-01

    Suspended-sediment concentration data were collected by the U.S. Geological Survey in San Francisco Bay during water year 2009 (October 1, 2008–September 30, 2009). Optical sensors and water samples were used to monitor suspended-sediment concentration at two sites in Suisun Bay, one site in San Pablo Bay, two sites in Central San Francisco Bay, and one site in South San Francisco Bay. Sensors were positioned at two depths at most sites to help define the vertical variability of suspended sediments. Water samples were collected periodically and analyzed for concentrations of suspended sediment. The results of the analyses were used to calibrate the output of the optical sensors so that a record of suspended-sediment concentrations could be derived. This report presents the data-collection methods used and summarizes, in graphs, the suspended-sediment concentration data collected from October 2008 through September 2009. Calibration curves and plots of the processed data for each sensor also are presented.

  8. Summary of Suspended-Sediment Concentration Data, San Francisco Bay, California, Water Year 2006

    USGS Publications Warehouse

    Buchanan, Paul A.; Lionberger, Megan A.

    2009-01-01

    Suspended-sediment concentration data were collected by the U.S. Geological Survey in San Francisco Bay during water-year 2006 (October 1, 2005-September 30, 2006). Optical sensors and water samples were used to monitor suspended-sediment concentration at two sites in Suisun Bay, one site in San Pablo Bay, two sites in Central San Francisco Bay, and one site in South San Francisco Bay. Sensors were positioned at two depths at most sites to help define the vertical variability of suspended sediments. Water samples were collected periodically and analyzed for concentrations of suspended sediment. The results of the analyses were used to calibrate the output of the optical sensors so that a record of suspended-sediment concentrations could be derived. This report presents the data-collection methods used and summarizes, in graphs, the suspended-sediment concentration data collected from October 2005 through September 2006. Calibration curves and plots of the processed data for each sensor also are presented.

  9. Modelling aftershock migration and afterslip of the San Juan Bautista, California, earthquake of October 3, 1972

    USGS Publications Warehouse

    Wesson, R.L.

    1987-01-01

    The San Juan Bautista earthquake of October 3, 1972 (ML = 4.8), located along the San Andreas fault in central California, initiated an aftershock sequence characterized by a subtle, but perceptible, tendency for aftershocks to spread to the northwest and southeast along the fault zone. The apparent dimension of the aftershock zone along strike increased from about 7-10 km within a few days of the earthquake, to about 20 km eight months later. In addition, the mainshock initiated a period of accelerated fault creep, which was observed at 2 creep meters situated astride the trace of the San Andreas fault within about 15 km of the epicenter of the mainshock. The creep rate gradually returned to the preearthquake rate after about 3 yrs. Both the spreading of the aftershocks and the rapid surface creep are interpreted as reflecting a period of rapid creep in the fault zone representing the readjustment of stress and displacement following the failure of a "stuck" patch or asperity during the San Juan Bautista earthquake. Numerical calculations suggest that the behavior of the fault zone is consistent with that of a material characterized by a viscosity of about 3.6??1014 P, although the real rheology is likely to be more complicated. In this model, the mainshock represents the failure of an asperity that slips only during earthquakes. Aftershocks represent the failure of second-order asperities which are dragged along by the creeping fault zone. ?? 1987.

  10. A Mass Balance for Mercury in the San Francisco Bay Area

    SciTech Connect

    MacLeod, Matthew; McKone, Thomas E.; Mackay, Don

    2005-06-01

    We develop and illustrate a general regional multi-species model that describes the fate and transport of mercury in three forms, elemental, divalent, and methylated, in a generic regional environment including air, soil, vegetation, water and sediment. The objectives of the model are to describe the fate of the three forms of mercury in the environment and determine the dominant physical sinks that remove mercury from the system. Chemical transformations between the three groups of mercury species are modeled by assuming constant ratios of species concentrations in individual environmental media. They illustrate and evaluate the model with an application to describe the fate and transport of mercury in the San Francisco Bay Area of California. The model successfully rationalizes the identified sources with observed concentrations of total mercury and methyl mercury in the San Francisco Bay Estuary. The mass balance provided by the model indicates that continental and global background sources control mercury concentrations in the atmosphere but loadings to water in the San Francisco Bay estuary are dominated by runoff from the Central Valley catchment and re-mobilization of contaminated sediments deposited during past mining activities. The model suggests that the response time of mercury concentrations in the San Francisco Bay estuary to changes in loadings is long, of the order of 50 years.

  11. Detecting areas disturbed by mining activities through Landsat images, San Luis Potosi City, Mexico

    NASA Astrophysics Data System (ADS)

    Torres-Vera, M.-A.

    2009-04-01

    Mining history in San Luis Potosí (Mexico) goes back to more than four centuries, and the accumulation of mining waste poses an important problem to ecological risk prevention. Epithermal deposits are the most common in this region and the impact of mining exploitation must be evaluated to propose sustainable development of the natural resources, which have a strong contribution of the national economy. The state San Luis Potosi is situated in the central part of Mexico between parallels 21°11' and 24°34' of north latitude and 98°23' and 102°14' of west longitude, 424 km northeast from Mexico City. Today is a sprawling city with more than half a million residents. The aim of this study was to analyse land cover and vegetation changes between 1972 and 2000 in San Luis Potosi Valley, using satellite image data. Since large changes in land cover and vegetation are taking place in the Valley and there is a lack of good data, such as maps, statistics and aerial photographs, it was appropriate to use satellite data for assessment of land cover and vegetation to estimate the environmental impact of the mining industry. Field data samples were used to evaluate the change results obtained with the multispectral satellite images. The results show that land cover change in the San Luis Potosi Valley has occurred in the past decade as a result of both natural forces and human activities, which have in turn impacted on the regional sustainable development of the mining resources.

  12. Aerial views of the San Andreas Fault

    USGS Publications Warehouse

    Moore, M.

    1988-01-01

    These aerial photographs of the San Andreas fault were taken in 1965 by Robert E. Wallace of the U.S Geological Survey. The pictures were taken with a Rolliflex camera on 20 format black and white flim; Wallace was aboard a light, fixed-wing aircraft, flying mostly at low altitudes. He photographed the fault from San Francisco near its north end where it enters by the Salton Sea. These images represent only a sampling of the more than 300 images prodcued during this project. All the photographs reside in the U.S Geological Survey Library in Menlo Park, California. 

  13. The San Francisco volcanic field, Arizona

    USGS Publications Warehouse

    Priest, S.S.; Duffield, W.A.; Malis-Clark, Karen; Hendley, J. W.; Stauffer, P.H.

    2001-01-01

    Northern Arizona's San Francisco Volcanic Field, much of which lies within Coconino and Kaibab National Forests, is an area of young volcanoes along the southern margin of the Colorado Plateau. During its 6-million-year history, this field has produced more than 600 volcanoes. Their activity has created a topographically varied landscape with forests that extend from the Pi?on-Juniper up to the Bristlecone Pine life zones. The most prominent landmark is San Francisco Mountain, a stratovolcano that rises to 12,633 feet and serves as a scenic backdrop to the city of Flagstaff.

  14. San Marcos Astronomical Project and Doctoral Prospectus

    NASA Astrophysics Data System (ADS)

    Aguilar, M. L.

    2009-05-01

    The Universidad Nacional Mayor de San Marcos, UNMSM, in Lima, Perú, is the only Peruvian institution working for the peruvian astronomical development as a career since 1970. We are conforming a network with international friend astronomers to invite them as Visiting Lectures to assure the academic level for the future doctoral studies in the UNMSM. The Chancellor of UNMSM has decided that the Astronomical Project is a UNMSM Project, to encourage and advance in this scientific and strategical area, to impulse the modernity of Peru, the major effort will be the building of the San Marcos Astronomical Observatory, with a telescope of 1 meter aperture.

  15. Fault-crossing P delays, epicentral biasing, and fault behavior in Central California

    USGS Publications Warehouse

    Marks, S.M.; Bufe, C.G.

    1979-01-01

    The P delays across the San Andreas fault zone in central California have been determined from travel-time differences at station pairs spanning the fault, using off-fault local earthquake or quarry blast sources. Systematic delays as large as 0.4 sec have been observed for paths crossing the fault at depths of 5-10 km. These delays can account for the apparent deviation of epicenters from the mapped fault trace. The largest delays occur along the San Andreas fault between San Juan Bautista and Bear Valley and Between Bitterwater Valley and Parkfield. Spatial variations in fault behavior correlate with the magnitude of the fault-crossing P delay. The delay decreases to the northwest of San Juan Bautista across the "locked" section of the San Andreas fault and also decreases to the southeast approaching Parkfield. Where the delay is large, seismicity is relatively high and the fault is creeping. ?? 1979.

  16. Geologic map of the Cochetopa Park and North Pass Calderas, northeastern San Juan Mountains, Colorado

    USGS Publications Warehouse

    Lipman, Peter W.

    2012-01-01

    The San Juan Mountains in southwestern Colorado have long been known as a site of exceptionally voluminous mid-Tertiary volcanism, including at least 22 major ignimbrite sheets (each 150-5,000 km3) and associated caldera structures active at 33-23 Ma. Recent volcanologic and petrologic studies in the San Juan region have focused mainly on several ignimbrite-caldera systems: the southeastern area (Platoro complex), western calderas (Uncompahgre-Silverton-Lake City), and the central cluster (La Garita-Creede calderas). Far less studied has been the northeastern San Juan region, which occupies a transition between earlier volcanism in central Colorado and large-volume younger ignimbrite-caldera foci farther south and west. The present map is based on new field coverage of volcanic rocks in seventeen 7.5' quadrangles in northeastern parts of the volcanic field, high-resolution age determinations for 120 new sites, and petrologic studies involving several hundred new chemical analyses. This mapping and the accompanying lab results (1) document volcanic evolution of the previously unrecognized North Pass caldera and the morphologically beautifully preserved but enigmatic Cochetopa basin, including unique features not previously described from ignimbrite calderas elsewhere; (2) provide evidence for a more rapid recurrence of large ignimbrite eruptions than previously known elsewhere; (3) quantify the regional time-space-volume progression from the earlier Sawatch magmatic trend southward into the San Juan region; and (4) permit more rigorous comparison between the broad mid-Tertiary magmatic belt in the western U.S. Cordillera and the type continental-margin arc volcanism in the central Andes.

  17. Deep structure in the region of the San Fernando and Santa Clarita Valleys, southern California, from LARSE II seismic imaging, earthquake relocation, and magnetic modeling -- a progress report

    NASA Astrophysics Data System (ADS)

    Fuis, G. S.; Ryberg, T.; Lutter, W. J.; Hauksson, E.; Richards-Dinger, K. B.; Hildenbrand, T. G.; Langenheim, V. E.; Murphy, J. M.; Okaya, D. A.

    2001-12-01

    The Los Angeles Region Seismic Experiment has as its chief goal seismic imaging of sedimentary basins and faults in the Los Angeles region in order to address earthquake hazards posed by these geologic features. Two 150-km-long transects were investigated, one (LARSE I) crossing the Los Angeles basin and San Gabriel Mts in a northeasterly direction through the vicinity of the 1987 M 5.9 Whittier Narrows earthquake, and a second (LARSE II) crossing the San Fernando Valley (SFV) and Santa Clarita Valley (SCV) in a northerly direction through the vicinities of the 1994 M 6.7 Northridge and 1971 M 6.7 San Fernando earthquakes. Along the LARSE II profile, seismic reflection data and relocated earthquakes suggest that the Northridge fault is a relatively simple plane dipping ~30o southward from ~8 km depth beneath the Santa Susana Mts (between the SFV and SCV) to the 1994 hypocenter at ~19 km depth. Relocated hypocenters suggest a deep part of the Santa Susana fault was activated during the Northridge aftershock sequence. In contrast, the 1971 San Fernando earthquake appears to have activated several faults in addition to the two rupture planes inferred by Heaton (1982), including the Northridge Hills blind thrust fault and a deep part of the San Gabriel fault. These two faults truncate reflections from the bottoms of the sedimentary basins in the SFV and SCV. We interpret the Northridge Hills blind thrust fault to truncate basin-bottom reflections beneath the SFV at ~5-6 km depth in the northern part of the SFV, and the San Gabriel fault to truncate similar reflections at ~3.5-4.5 km depth beneath the central part of the SCV. The San Gabriel fault projects to the 1971 hypocenter. In between the Northridge Hills blind thrust and San Gabriel faults, reflections are largely incoherent, and the velocity structure is complex. Below the 1971 hypocenter (at ~13 km depth), the San Fernando fault appears to be contained in a broad north-dipping zone of reflectivity in which

  18. Basement plan. San Bernardino Valley Union Junior College, Auditorium building. ...

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

    Basement plan. San Bernardino Valley Union Junior College, Auditorium building. G. Stanley Wilson, Architect, A.I.A., Riverside, California. Sheet 2, Job no. 692. Scale 1/8 inch to the foot. March 27, 1936. Application no. 1446, approved by the State of California, Department of Public Works, Division of Architecture, April 22, 1936. - San Bernardino Valley College, Auditorium, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  19. Rose windows and other details. San Bernardino Valley Union Junior ...

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

    Rose windows and other details. San Bernardino Valley Union Junior College, Auditorium Building. Rose window; front windows; drinking fountain alcove; proscenium arch; stage door. G. Stanley Wilson, Architect, A.I.A., Riverside, California. Sheet 12, job no. 692. Various scales. March 27, 1936. Application no. 1446, approved by the State of California, Department of Public Works, Division of Architecture, April 22, 1936. - San Bernardino Valley College, Auditorium, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  20. Sections. Ceiling plan. San Bernardino Valley Union Junior College, Auditorium ...

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

    Sections. Ceiling plan. San Bernardino Valley Union Junior College, Auditorium Building. G. Stanley Wilson, Architect, A.I.A., Riverside, California. Sheet 9, job no. 692. Scale 1/8 inch to the foot. March 27, 1936. Application no. 1446, approved by the State of California, Department of Public Works, Division of Architecture, April 22, 1936. - San Bernardino Valley College, Auditorium, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  1. Detail of proscenium opening. San bernardino Valley Union Junior College, ...

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

    Detail of proscenium opening. San bernardino Valley Union Junior College, Auditorium Building. Details of corbels and soffit; lettering detail for frieze. G. Stanley Wilson, Architect, A.I.A., Riverside, California. Sheet W.P.A. 2, job no. 692. Scale 3/4 inch to the foot. May 18, 1937. (no state stamp. - San Bernardino Valley College, Auditorium, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  2. Tower details, sheet 16. San Bernardino Valley Union Junior College, ...

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

    Tower details, sheet 16. San Bernardino Valley Union Junior College, Auditorium Building. Clock and finial details; tower roof plan. G. Stanley Wilson, Architect, A.I.A., Riverside, California. Sheet 16, job no. 692. Various scales. July 15, 1937. Application no. 1446, approved by the State of California, Department of Public Works, Division of Architecture, July 24, 1937. - San Bernardino Valley College, Auditorium, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  3. Second floor plan. San Bernardino Valley Union Junior College, Auditorium ...

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

    Second floor plan. San Bernardino Valley Union Junior College, Auditorium Building. G. Stanley Wilson, Architect, A.I.A., Riverside, California. Sheet 4, job no. 692. Scale 1/8 inch to the foot. March 27, 1936. Application no. 1446, approved by the State of California, Department of Public Works, Division of Architecture, April 22, 1936. - San Bernardino Valley College, Auditorium, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  4. Plot plan. San Bernardino Valley Union Junior College, Auditorium building. ...

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

    Plot plan. San Bernardino Valley Union Junior College, Auditorium building. G. Stanley Wilson, Architect, A.I.A., Riverside, California. Sheet 1, job no. 692. Scale 1 inch to forty feet. March 27, 1936. Application no. 1446, approved by the State of California, Department of Public Works, Division of Architecture, April 22, 1936. - San Bernardino Valley College, Auditorium, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  5. Radar image San Francisco Bay Area, California

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The San Francisco Bay Area in California and its surroundings are shown in this radar image from the Shuttle Radar Topography Mission (SRTM). On this image, smooth areas, such as the bay, lakes, roads and airport runways appear dark, while areas with buildings and trees appear bright. Downtown San Francisco is at the center and the city of Oakland is at the right across the San Francisco Bay. Some city areas, such as the South of Market district in San Francisco, appear bright due to the alignment of streets and buildings with respect to the incoming radar beam. Three of the bridges spanning the Bay are seen in this image. The Bay Bridge is in the center and extends from the city of San Francisco to Yerba Buena and Treasure Islands, and from there to Oakland. The Golden Gate Bridge is to the left and extends from San Francisco to Sausalito. The Richmond-San Rafael Bridge is in the upper right and extends from San Rafael to Richmond. Angel Island is the large island east of the Golden Gate Bridge, and lies north of the much smaller Alcatraz Island. The Alameda Naval Air Station is seen just below the Bay Bridge at the center of the image. Two major faults bounding the San Francisco-Oakland urban areas are visible on this image. The San Andreas fault, on the San Francisco peninsula, is seen on the left side of the image. The fault trace is the straight feature filled with linear reservoirs, which appear dark. The Hayward fault is the straight feature on the right side of the image between the urban areas and the hillier terrain to the east.

    This radar image was acquired by just one of SRTM's two antennas and, consequently, does not show topographic data, but only the strength of the radar signal reflected from the ground. This signal, known as radar backscatter, provides insight into the nature of the surface, including its roughness, vegetation cover and urbanization. The overall faint striping pattern in the images is a data processing artifact due to the

  6. Sans study of asphaltene aggregation

    SciTech Connect

    Overfield, R.E.; Sheu, E.Y.; Sinha, S.K.; Liang, K.S. )

    1988-06-01

    The colloidal properties of asphaltenes have long been recognized from peculiarities in their solubility and colligative properties. A layered micellar model or asphaltenes was proposed by others in which a highly condensed alkyl aromatic formed the central part, and molecules of decreasingly aromatic character (resins) clustered around them. Numerous studies, based on a variety of techniques such as ultracentrifugation and electron microscopy indicated a particulate nature for asphaltenes with size 20-40 A diameter. Others have proposed a refined model based on x-ray diffraction and small angle scattering. In this model, interactions between flat sheets of condensed aromatic rings form the central ''crystallite'' part of a spherical particle with the outer part being comprised of the aliphatic positions of the same molecules. These particles are bunched together with some degree of entanglement into ''micelles''. Concentration and solvent dependent radii of gyration, ranging from 30-50 A were reported. The aggregation creates a good deal of uncertainty as to the true molecular size or weight of asphaltenes. Neutron scattering offers novel contrast relative to light scattering (refractive index) and x-ray scattering (electron density). This is because the scattering length of proton is negative, whereas that from deuterium and other nuclei such as C, S, O, and N are positive. Thus by replacing hydrogen with deuterium in either the solvent or the scatterer the contrast can be varied, and different parts of the molecule can be highlighted.

  7. Sans study of asphaltene aggregration

    SciTech Connect

    Overfield, R.E.; Sheu, E.Y.; Sinha, S.K.; Liang, K.S. )

    1988-06-01

    The colloidal properties of asphaltenes have long been recognized from peculiarities in their solubility and colligative properties. A layered micellar model for asphaltenes was proposed by Pfeiffer and Saal in 1940, in which a highly condensed alkyl aromatic formed the central part, and molecules of decreasingly aromatic character (resins) clustered around them. Numerous studies, based on a variety of techniques such as ultracentrifugation and electron microscopy indicated a particulate nature for asphaltenes with size 20-40 {angstrom} diameter. T.F. Yen and co-workers proposed a refined model based on x-ray diffraction and small angle scattering. In this model, interactions between flat sheets of condensed aromatic rings form the central crystallite part of a spherical particle with the outer part being comprised of the aliphatic positions of the same molecules. These particles are bunched together with some degree of entanglement into micelles. Concentration and solvent dependent radii of gyration, ranging from 30-50 {angstrom} were reported. The aggregation creates a good deal of uncertainty as to the true molecular size of weight of asphaltenes. Neutron scattering offers novel contrast relative to light scattering (refractive index) and x-ray scattering (electron density). This is because the scattering length of proton is negative, whereas that from deuterium and other nuclei such as C, S, O, and N are positive. Thus by replacing hydrogen with deuterium in either the solvent or the scatterer the contrast can be varied, and different parts of the molecule can be highlighted.

  8. San Diego County Adopt-A-School Program.

    ERIC Educational Resources Information Center

    San Diego County Dept. of Education, CA.

    The San Diego County (California) Adopt-A-School program, established in the spring of 1982, is a partnership program that has paired San Diego schools at all grade levels with local businesses, military commands, and service organizations. The purpose of Adopt-A-School is to foster better understanding of public schools in San Diego, strengthen…

  9. 75 FR 71179 - Environmental Impact Statement: San Diego County, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-22

    ... Federal Highway Administration Environmental Impact Statement: San Diego County, CA AGENCY: Federal... Environmental Impact Statement (EIS) will be prepared ] for a proposed highway project in San Diego County... Community Center, 2258 Island Avenue, San Diego, California 92102. FOR FURTHER INFORMATION CONTACT:...

  10. 33 CFR 110.210 - San Diego Harbor, CA.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false San Diego Harbor, CA. 110.210... ANCHORAGE REGULATIONS Anchorage Grounds § 110.210 San Diego Harbor, CA. (a) The anchorage grounds. (1... Commander, Naval Base, San Diego, CA. The administration of these anchorages is exercised by the...

  11. 76 FR 27304 - Pike & San Isabel Resource Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-11

    ... Forest Service Pike & San Isabel Resource Advisory Committee AGENCY: Forest Service, USDA. ACTION: Notice of meeting. SUMMARY: The Pike & San Isabel Resource Advisory Committee will meet in Pueblo, Colorado... Pike & San Isabel National Forests, Cimarron and Comanche National Grasslands (PSICC) at 2840...

  12. 76 FR 2331 - Pike & San Isabel Resource Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-13

    ... Forest Service Pike & San Isabel Resource Advisory Committee AGENCY: Forest Service, USDA. ACTION: Notice of meeting. SUMMARY: The Pike & San Isabel Resource Advisory Committee will meet in Pueblo, Colorado... of the Pike & San Isabel National Forests, Cimarron and Comanche National Grasslands (PSICC) at...

  13. 27 CFR 9.25 - San Pasqual Valley.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false San Pasqual Valley. 9.25... OF THE TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.25 San Pasqual Valley. (a) Name. The name of the viticultural area described in this section is “San...

  14. 27 CFR 9.25 - San Pasqual Valley.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false San Pasqual Valley. 9.25... OF THE TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.25 San Pasqual Valley. (a) Name. The name of the viticultural area described in this section is “San...

  15. 75 FR 78675 - Pike & San Isabel Resource Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-16

    ... Forest Service Pike & San Isabel Resource Advisory Committee AGENCY: Forest Service, USDA. ACTION: Notice of meeting. SUMMARY: The Pike & San Isabel Resource Advisory Committee will meet in Pueblo, Colorado... of the Pike & San Isabel National Forests, Cimarron and Comanche National Grasslands (PSICC) at...

  16. 78 FR 48646 - Pike & San Isabel Resource Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-09

    ... Forest Service Pike & San Isabel Resource Advisory Committee AGENCY: Forest Service, USDA. ACTION: Notice of meetings. SUMMARY: The Pike & San Isabel Resource Advisory Committee will meet in Pueblo, Colorado... at the Supervisor's Office of the Pike & San Isabel National Forests, Cimarron and Comanche...

  17. 33 CFR 110.210 - San Diego Harbor, CA.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false San Diego Harbor, CA. 110.210... ANCHORAGE REGULATIONS Anchorage Grounds § 110.210 San Diego Harbor, CA. (a) The anchorage grounds. (1... Commander, Naval Base, San Diego, CA. The administration of these anchorages is exercised by the...

  18. 27 CFR 9.194 - San Antonio Valley.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false San Antonio Valley. 9.194... OF THE TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.194 San Antonio Valley. (a) Name. The name of the viticultural area described in this section is “San...

  19. 33 CFR 165.1107 - San Diego Bay, California.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false San Diego Bay, California. 165... Navigation Areas and Limited Access Areas Eleventh Coast Guard District § 165.1107 San Diego Bay, California... docking/undocking operations at the U.S. Naval Submarine Base on Ballast Point, San Diego Bay,...

  20. 27 CFR 9.130 - San Ysidro District.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false San Ysidro District. 9.130... OF THE TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.130 San Ysidro District. (a) Name. The name of the viticultural area described in this section is “San...

  1. 76 FR 30903 - Pike & San Isabel Resource Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-27

    ... Forest Service Pike & San Isabel Resource Advisory Committee AGENCY: Forest Service, USDA. ACTION: Notice of meeting. SUMMARY: The Pike & San Isabel Resource Advisory Committee will meet in Pueblo, Colorado... of the Pike & San Isabel National Forests, Cimarron and Comanche National Grasslands (PSICC) at...

  2. 33 CFR 110.120 - San Luis Obispo Bay, Calif.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false San Luis Obispo Bay, Calif. 110... ANCHORAGES ANCHORAGE REGULATIONS Special Anchorage Areas § 110.120 San Luis Obispo Bay, Calif. (a) Area A-1. Area A-1 is the water area bounded by the San Luis Obispo County wharf, the shoreline, a line...

  3. 76 FR 9540 - Pike & San Isabel Resource Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-18

    ... Forest Service Pike & San Isabel Resource Advisory Committee AGENCY: Forest Service, USDA. ACTION: Notice of meeting. SUMMARY: The Pike & San Isabel Resource Advisory Committee will meet in Pueblo, Colorado... of the Pike & San Isabel National Forests, Cimarron and Comanche National Grasslands (PSICC) at...

  4. 75 FR 51749 - Pike & San Isabel Resource Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-23

    ... Forest Service Pike & San Isabel Resource Advisory Committee AGENCY: Forest Service, USDA. ACTION: Notice of meeting. SUMMARY: The Pike & San Isabel Resource Advisory Committee will meet in Pueblo, Colorado... Pike & San Isabel National Forests, Cimarron and Comanche National Grasslands (PSICC) at 2840...

  5. 33 CFR 110.120 - San Luis Obispo Bay, Calif.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false San Luis Obispo Bay, Calif. 110... ANCHORAGES ANCHORAGE REGULATIONS Special Anchorage Areas § 110.120 San Luis Obispo Bay, Calif. (a) Area A-1. Area A-1 is the water area bounded by the San Luis Obispo County wharf, the shoreline, a line...

  6. 27 CFR 9.130 - San Ysidro District.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false San Ysidro District. 9.130... OF THE TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.130 San Ysidro District. (a) Name. The name of the viticultural area described in this section is “San...

  7. 77 FR 47358 - San Juan National Forest Resource Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-08

    ... Forest Service San Juan National Forest Resource Advisory Committee AGENCY: Forest Service, USDA. ACTION: Notice of meeting. SUMMARY: The San Juan National Forest Resource Advisory Council (RAC) will meet in...: The meeting will be held at the San Juan Public Lands Center, 15 Burnett Court, Durango, Colorado...

  8. 33 CFR 165.1107 - San Diego Bay, California.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false San Diego Bay, California. 165... Navigation Areas and Limited Access Areas Eleventh Coast Guard District § 165.1107 San Diego Bay, California... docking/undocking operations at the U.S. Naval Submarine Base on Ballast Point, San Diego Bay,...

  9. 75 FR 65609 - Pike & San Isabel Resource Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-26

    ... Forest Service Pike & San Isabel Resource Advisory Committee AGENCY: Forest Service, USDA. ACTION: Notice of meeting. SUMMARY: The Pike & San Isabel Resource Advisory Committee will meet in Pueblo, Colorado... Supervior's Office of the Pike & San Isabel National Forests, Cimarron and Comanche National...

  10. 33 CFR 161.50 - Vessel Traffic Service San Francisco.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Vessel Traffic Service San... Movement Reporting System Areas and Reporting Points § 161.50 Vessel Traffic Service San Francisco. The VTS area consists of all the navigable waters of San Francisco Bay Region south of the Mare Island...

  11. 77 FR 66910 - Environmental Impact Statement, San Diego County, California

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-07

    ... San Diego County, California (Federal Register Vol. 72, No 10; FR Doc E7-491) will be withdrawn. FOR... Federal Highway Administration Environmental Impact Statement, San Diego County, California AGENCY... Highway Administration--California Division, 401 B Street, Suite 800, San Diego, CA 92101, Regular...

  12. 76 FR 40876 - San Juan National Forest Resource Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-12

    ... Forest Service San Juan National Forest Resource Advisory Committee AGENCY: Forest Service, USDA. ACTION: Notice of meeting. SUMMARY: The San Juan National Forest Resource Advisory Council (RAC) will meet in... meeting will be held at the San Juan Public Lands Center, 15 Burnett Court, Durango, Colorado in...

  13. 33 CFR 161.50 - Vessel Traffic Service San Francisco.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Vessel Traffic Service San... Movement Reporting System Areas and Reporting Points § 161.50 Vessel Traffic Service San Francisco. The VTS area consists of all the navigable waters of San Francisco Bay Region south of the Mare Island...

  14. 77 FR 50459 - Pike & San Isabel Resource Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-21

    ... Forest Service Pike & San Isabel Resource Advisory Committee AGENCY: Forest Service, USDA. ACTION: Notice of meetings. SUMMARY: The Pike & San Isabel Resource Advisory Committee will meet in Pueblo, Colorado... will be held at the Supervisor's Office of the Pike & San Isabel National Forests, Cimarron...

  15. 33 CFR 161.50 - Vessel Traffic Service San Francisco.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... the San Joaquin River, as far north as the port of Sacramento on the Sacramento River. ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Vessel Traffic Service San... Movement Reporting System Areas and Reporting Points § 161.50 Vessel Traffic Service San Francisco. The...

  16. Ecology and management of savannas and semi-deserts of central Argentina

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vegetation of western pampas of central Argentina comprises: caldera, local name of a savanna to woodland ecosystem dominated by Prosopis caldenia; short-grassland and dune-grassland. The area include the central La Pampa and southern San Luis provinces, following a western precipitation gradient fr...

  17. 33 CFR 3.55-20 - Sector San Francisco: San Francisco Bay Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Sector San Francisco: San..., MARINE INSPECTION ZONES, AND CAPTAIN OF THE PORT ZONES Eleventh Coast Guard District § 3.55-20 Sector San Francisco: San Francisco Bay Marine Inspection Zone and Captain of the Port Zone. The Sector San...

  18. 33 CFR 3.55-20 - Sector San Francisco: San Francisco Bay Marine Inspection Zone and Captain of the Port Zone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Sector San Francisco: San..., MARINE INSPECTION ZONES, AND CAPTAIN OF THE PORT ZONES Eleventh Coast Guard District § 3.55-20 Sector San Francisco: San Francisco Bay Marine Inspection Zone and Captain of the Port Zone. The Sector San...

  19. The Third International San Francisco Book Fair.

    ERIC Educational Resources Information Center

    Kalmon, Winn; And Others

    Friends of Books and Comics presents its catalog of the Third International San Francisco Book Fair, a marketplace of alternative books, comics, and magazines. Nearly 200 alternative and small presses are listed alphabetically with address, telephone number, names of principal people involved, and a brief description of type and subject of…

  20. San Miguel High School: Focus and Preparation

    ERIC Educational Resources Information Center

    Principal Leadership, 2010

    2010-01-01

    The corporate internship program is a cornerstone of the education that students receive at San Miguel High School in Tucson, Arizona. Four students share one job, so each student works for a corporate partner outside of the school every fourth day. The money they earn is used to help defray the cost of their education, and the experience is…

  1. San Francisco, California: Solar in Action (Brochure)

    SciTech Connect

    Not Available

    2011-10-01

    This brochure provides an overview of the challenges and successes of San Francisco, CA, a 2007 Solar America City awardee, on the path toward becoming a solar-powered community. Accomplishments, case studies, key lessons learned, and local resource information are given.

  2. Nathaniel Hawthorne Elementary School: San Antonio, Texas.

    ERIC Educational Resources Information Center

    American Educator, 1997

    1997-01-01

    Discusses the successful use of Core Knowledge Curriculum in one inner-city elementary school in San Antonio (Texas) that had previously reflected low student achievement, inconsistent attendance, and student behavioral problems. Improvements in these conditions as revealed through teacher observations are highlighted. (GR)

  3. Humanities at College of San Mateo.

    ERIC Educational Resources Information Center

    San Mateo Coll., CA.

    Descriptions are provided for the courses in the College of San Mateo's new Humanities program. As introductory material notes, these team-taught, interdisciplinary courses were designed to be taken independently in various combinations depending upon the student's major or interests. They carry three units of transferable credit and satisfy…

  4. 77 FR 20379 - San Diego Gas &

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-04

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission San Diego Gas & Electric Company v. Sellers of Energy and Ancillary Services Into Markets Operated by the California Independent System Operator Corporation and the...

  5. Simulations of the 1906 San Francisco Earthquake

    SciTech Connect

    Rodgers, A; Petersson, A; Tkalcic, H

    2005-12-16

    Simulations of the Great 1906 San Francisco earthquake are being performed as part of the event's centenary. LLNL is participating in a large effort to study this event and possible consequences if the event were to happen today. This document is meant to describe our efforts to others participating in the project.

  6. San Jose, California: Solar in Action (Brochure)

    SciTech Connect

    Not Available

    2011-10-01

    This brochure provides an overview of the challenges and successes of San Jose, CA, a 2008 Solar America City awardee, on the path toward becoming a solar-powered community. Accomplishments, case studies, key lessons learned, and local resource information are given.

  7. San Antonio, Texas: Solar in Action (Brochure)

    SciTech Connect

    Not Available

    2011-10-01

    This brochure provides an overview of the challenges and successes of San Antonio, TX, a 2008 Solar America City awardee, on the path toward becoming a solar-powered community. Accomplishments, case studies, key lessons learned, and local resource information are given.

  8. Educational and Demographic Profile: San Benito County.

    ERIC Educational Resources Information Center

    California Postsecondary Education Commission, 2004

    2004-01-01

    This profile uniquely presents a variety of educational and socioeconomic information for San Benito County, nearby counties, and the state. The profile highlights the relationship between various factors that affect the economic well-being of individuals and communities. This presentation of information provides a framework for enhanced…

  9. Potamocorbula amurensis discovered in San Francisco Bay

    USGS Publications Warehouse

    Schemel, Laurence E.

    1989-01-01

    The small Asian clam, Potamocorbula amurensis, is now a major component of benthic communities in most areas of northern San Francisco Bay and some areas of South Bay. Because of its wide tolerance of salinity and other environmental variables and its high abundance in many areas, benthic ecologists believe this recent invasion may represent a major and permanent change in the bay system.

  10. San Francisco's New Zoo's Connections for Conservation.

    ERIC Educational Resources Information Center

    Routman, Emily

    2001-01-01

    Provides information on a redevelopment project at the San Francisco Zoo known as the New Zoo. The explicit goal of the project is to inspire a sense of caring and appreciation for wildlife that is the foundation of a conservation ethic. (DDR)

  11. San Diego, California: Solar in Action (Brochure)

    SciTech Connect

    Not Available

    2011-10-01

    This brochure provides an overview of the challenges and successes of San Diego, CA, a 2007 Solar America City awardee, on the path toward becoming a solar-powered community. Accomplishments, case studies, key lessons learned, and local resource information are given.

  12. Zapotec Immigration: The San Lucas Quiavini Experience.

    ERIC Educational Resources Information Center

    Lopez, Felipe H.; Munro, Pamela

    1999-01-01

    Interviews with 20 Zapotec immigrants from Oaxaca (Mexico) to Los Angeles examined their immigration experiences and adjustment to life in the United States. Discussion covers immigration from Oaxaca; living conditions, illiteracy, education, and language usage in the village of San Lucas Quiavini; immigration patterns; ethnicity and Oaxacan…

  13. 27 CFR 9.171 - San Bernabe.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false San Bernabe. 9.171 Section 9.171 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF... benchmark 304, located one-half mile southwest of King City, along the Salinas River, in Township 20...

  14. 27 CFR 9.171 - San Bernabe.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false San Bernabe. 9.171 Section 9.171 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF... benchmark 304, located one-half mile southwest of King City, along the Salinas River, in Township 20...

  15. Computer-based PRA at San Onofre

    SciTech Connect

    1996-09-01

    Personal computer software, called Safety Monitor, used to perform probabilistic risk assessments (PRAs) is described. Safety Monitor assesses core damage and containment failure risks in less than 60 seconds. The software was developed by San Onofre PRA analysts and NUS Corporation. Operational use and cost savings are described.

  16. Academic Decathlon--San Diego County.

    ERIC Educational Resources Information Center

    San Diego County Office of Education, CA.

    Publicity materials and a brief program description of the 1983 San Diego County (California) Academic Decathlon are presented. The program description discusses the background, subject coverage, and rules of the Academic Decathlon, a program to promote academic excellence among high school juniors and seniors through competition. The Academic…

  17. Educational and Demographic Profile: San Joaquin County

    ERIC Educational Resources Information Center

    California Postsecondary Education Commission, 2004

    2004-01-01

    This profile uniquely presents a variety of educational and socioeconomic information for San Joaquin County, nearby counties, and the state. The profile highlights the relationship between various factors that affect the economic well-being of individuals and communities. This presentation of information provides a framework for enhanced…

  18. The San Joaquin Valley: 20 years later

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The history of irrigation development and the need for disposal of saline drainage water in the San Joaquin Valley was described to provide background for the drainage water disposal problem that resulted from the closure of the Kesterson Reservoir. A 5 year study developed in Valley alternatives fo...

  19. Desegregation in the South San Joaquin Valley.

    ERIC Educational Resources Information Center

    Serrano, Rodolfo G.

    Notably isolated from the large metropolitan centers by geography and predominantly agricultural in its economy, Kern County is California's third largest county in land area. About one-third of the county is situated on the flat valley floor at the extreme southern end of the San Joaquin Valley. The area relies heavily on Chicano and Black manual…

  20. San Joaquin Delta College Student Athlete Study.

    ERIC Educational Resources Information Center

    Lewis, Merrilee R.; Marcopulos, Ernest

    In spring 1988, a study was conducted of students who participated in college athletics at San Joaquin Delta College (SJDC) between 1983-84 and 1987-88. Data collected on each student athlete included ethnicity, sport, place of residence, initial and current reading level, total grade point average (GPA), GPA in athletics and physical education…

  1. Groundwater quality in the San Fernando--San Gabriel groundwater basins, California

    USGS Publications Warehouse

    Kulongoski, Justin T.; Belitz, Kenneth

    2012-01-01

    Groundwater provides more than 40 percent of California's drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State's groundwater quality and increases public access to groundwater-quality information. The San Fernando and San Gabriel groundwater basins constitute one of the study units being evaluated.

  2. 75 FR 8106 - Don Edwards San Francisco Bay National Wildlife Refuge, Alameda, Santa Clara, and San Mateo...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-23

    ... Fish and Wildlife Service Don Edwards San Francisco Bay National Wildlife Refuge, Alameda, Santa Clara, and San Mateo Counties, CA AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice of intent to...) and Environmental Assessment (EA) for the Don Edwards San Francisco Bay National Wildlife...

  3. 33 CFR 165.1185 - Regulated Navigation Area; San Francisco Bay, San Pablo Bay, Carquinez Strait, Suisun Bay...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (LHG)” is a liquid containing one or more of the products listed in Table 127.005 of 33 CFR 127.005... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Regulated Navigation Area; San Francisco Bay, San Pablo Bay, Carquinez Strait, Suisun Bay, Sacramento River, San Joaquin River,...

  4. 33 CFR 165.1185 - Regulated Navigation Area; San Francisco Bay, San Pablo Bay, Carquinez Strait, Suisun Bay...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (LHG)” is a liquid containing one or more of the products listed in Table 127.005 of 33 CFR 127.005... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Regulated Navigation Area; San Francisco Bay, San Pablo Bay, Carquinez Strait, Suisun Bay, Sacramento River, San Joaquin River,...

  5. 75 FR 8804 - Safety Zone; NASSCO Launching of USNS Charles Drew, San Diego Bay, San Diego, CA.

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-26

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; NASSCO Launching of USNS Charles Drew, San Diego Bay, San Diego, CA. AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a temporary safety zone on the navigable waters of the San Diego Bay in support...

  6. Geochronology and geology of late Oligocene through Miocene volcanism and mineralization in the western San Juan Mountains, Colorado

    USGS Publications Warehouse

    Bove, Dana J.; Hon, Ken; Budding, Karin E.; Slack, John F.; Snee, Lawrence W.; Yeoman, Ross A.

    2001-01-01

    This paper presents 25 new 40Ar/39Ar dates from the main calc-alkaline ash-flow sheets and related younger plutons of the western San Juan volcanic field, the ash-flow sheets of the Lake City caldera cycle, and veins and other altered rocks in the Lake City region. The goal of the study was to produce similar quality 40Ar/39Ar ages to those currently published for the eastern and central San Juan Mountains. These new data provide a much more precise chronological framework for interpreting durations of events and their relationship to mineralization than do previously published conventional K-Ar dates for the western San Juan Mountains.

  7. Estimating Natural Flows into the California's Sacramento - San Joaquin Delta

    NASA Astrophysics Data System (ADS)

    Huang, G.; Kadir, T.; Chung, F. I.

    2014-12-01

    Natural flows into the California's Sacramento - San Joaquin Delta under predevelopment vegetative conditions, if and when reconstructed, can serve as a useful guide to establish minimum stream flows, restoration targets, and a basis for assessing impacts of global warming in the Bay-Delta System. Daily simulations of natural Delta flows for the period 1922-2009 were obtained using precipitation-snowmelt-runoff models for the upper watersheds that are tributaries to the California's Central Valley, and then routing the water through the Central Valley floor area using a modified version of the California Central Valley Groundwater-Surface Water Simulation Model (C2VSIM) for water years 1922 through 2009. Daily stream inflows from all major upper watersheds were simulated using 23 Soil Water Assessment Tool (SWAT) models. Historical precipitation and reference evapotranspiration data were extracted from the SIMETAW2 with the 4km gridded meteorological data. The Historical natural and riparian vegetation distributions were compiled from several pre-1900 historical vegetation maps of the Central Valley. Wetlands were dynamically simulated using interconnected lakes. Flows overtopping natural levees were simulated using flow rating curves. New estimates of potential evapotranspiration from different vegetative classes under natural conditions were also used. Sensitivity simulations demonstrate that evapotranspiration estimates, native vegetation distribution, surface-groundwater interaction parameters, extinction depth for groundwater uptake, and other physical processes play a key role in the magnitude and timing of upstream flows arriving at the Delta. Findings contradict a common misconception that the magnitude of inflows to the Delta under natural vegetative conditions is greater than those under the historical agricultural and urban land use development. The developed models also enable to study the impacts of global warming by modifying meteorological and

  8. ASTER Images San Francisco Bay Area

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This image of the San Francisco Bay region was acquired on March 3, 2000 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters about 50 to 300 feet ), ASTER will image Earth for the next 6 years to map and monitor the changing surface of our planet.

    Image: This image covers an area 60 kilometers (37 miles) wide and 75 kilometers (47 miles) long in three bands of the reflected visible and infrared wavelength region. The combination of bands portrays vegetation in red, and urban areas in gray. Sediment in the Suisun Bay, San Pablo Bay, San Francisco Bay, and the Pacific Ocean shows up as lighter shades of blue. Along the west coast of the San Francisco Peninsula, strong surf can be seen as a white fringe along the shoreline. A powerful rip tide is visible extending westward from Daly City into the Pacific Ocean. In the lower right corner, the wetlands of the South San Francisco Bay National Wildlife Refuge appear as large dark blue and brown polygons. The high spatial resolution of ASTER allows fine detail to be observed in the scene. The main bridges of the area (San Mateo, San Francisco-Oakland Bay, Golden Gate, Richmond-San Rafael, Benicia-Martinez, and Carquinez) are easily picked out, connecting the different communities in the Bay area. Shadows of the towers along the Bay Bridge can be seen over the adjacent bay water. With enlargement the entire road network can be easily mapped; individual buildings are visible, including the shadows of the high-rises in downtown San Francisco.

    Inset: This enlargement of the San Francisco Airport highlights the high spatial resolution of ASTER. With further enlargement and careful examination, airplanes can be seen at the terminals.

    Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth

  9. A case for historic joint rupture of the San Andreas and San Jacinto faults

    PubMed Central

    Lozos, Julian C.

    2016-01-01

    The San Andreas fault is considered to be the primary plate boundary fault in southern California and the most likely fault to produce a major earthquake. I use dynamic rupture modeling to show that the San Jacinto fault is capable of rupturing along with the San Andreas in a single earthquake, and interpret these results along with existing paleoseismic data and historic damage reports to suggest that this has likely occurred in the historic past. In particular, I find that paleoseismic data and historic observations for the ~M7.5 earthquake of 8 December 1812 are best explained by a rupture that begins on the San Jacinto fault and propagates onto the San Andreas fault. This precedent carries the implications that similar joint ruptures are possible in the future and that the San Jacinto fault plays a more significant role in seismic hazard in southern California than previously considered. My work also shows how physics-based modeling can be used for interpreting paleoseismic data sets and understanding prehistoric fault behavior. PMID:27034977

  10. A case for historic joint rupture of the San Andreas and San Jacinto faults.

    PubMed

    Lozos, Julian C

    2016-03-01

    The San Andreas fault is considered to be the primary plate boundary fault in southern California and the most likely fault to produce a major earthquake. I use dynamic rupture modeling to show that the San Jacinto fault is capable of rupturing along with the San Andreas in a single earthquake, and interpret these results along with existing paleoseismic data and historic damage reports to suggest that this has likely occurred in the historic past. In particular, I find that paleoseismic data and historic observations for the ~M7.5 earthquake of 8 December 1812 are best explained by a rupture that begins on the San Jacinto fault and propagates onto the San Andreas fault. This precedent carries the implications that similar joint ruptures are possible in the future and that the San Jacinto fault plays a more significant role in seismic hazard in southern California than previously considered. My work also shows how physics-based modeling can be used for interpreting paleoseismic data sets and understanding prehistoric fault behavior. PMID:27034977

  11. Mezzanine plan and north elevation. San Bernardino Valley Union Junior ...

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

    Mezzanine plan and north elevation. San Bernardino Valley Union Junior College, library building. Also includes interior elevation of wall between windows, showing light receptacle and section through beam. Howard E. Jones, Architect, San Bernardino, California. Sheet 3, job no. 315. Scales 1/8 inch to the foot (plan, elevation) and 1/2 inch to the foot (interior elevation). No date given on sheet (probably March or April, 1927). - San Bernardino Valley College, Library, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  12. Floor plan and front elevation. San Bernardino Valley Union Junior ...

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

    Floor plan and front elevation. San Bernardino Valley Union Junior College, Library Building. Also includes detail of concrete grille; sections QQ and TT; and detail of bulletin board. Howard E. Jones, Architect, San Bernardino, California. Sheet 2, job no. 315. Scales 1/8 inch to the foot (plan, elevation), 1/2 inch to the foot (sections), and 1/4 inch to the foot (bulletin board). No date given on sheet (probably March or April, 1927). - San Bernardino Valley College, Library, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  13. North & south elevations. San Bernardino Valley Union Junior College, ...

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

    North & south elevations. San Bernardino Valley Union Junior College, Classics Building. Also includes longitudinal sections through the boiler room, plan of chimney, elevations of counter in the bookkeeping room, and detail of trusses over the oral English room. Howard E. Jones, Architect, San Bernardino, California. Sheet 4, job no. 312. Scales 1/8 inch to the foot and 1/2 inch to the foot. February 15, 1927. - San Bernardino Valley College, Classics Building, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  14. Inferences drawn from two decades of alinement array measurements of creep on faults in the San Francisco Bay Region

    USGS Publications Warehouse

    Galehouse, J.S.; Lienkaemper, J.J.

    2003-01-01

    We summarize over 20 years of monitoring surface creep on faults of the San Andreas system in the San Francisco Bay region using alinement arrays. The San Andreas fault is fully locked at five sites northwest from San Juan Bautista, the southern end of the 1906 earthquake rupture, that is, no creep (< 1 mm/yr) is observed. Likewise, the San Gregorio, Rodgers Creek, and West Napa faults show no creep. The measured creep rate on the Calaveras-Paicines fault from Hollister southward is either 6 or ??? 10 mm/yr, depending on whether the arrays cross all of the creeping traces. Northward of Hollister, the central Calaveras creep rate reaches 14 ?? 2 mm/yr but drops to ??? 2 mm/yr near Calaveras Reservoir, where slip transfers to the southern Hayward fault at a maximum creep rate of 9 mm/yr at its south end. However, the Hayward fault averages only 4.6 mm/yr over most of its length. The Northern Calaveras fault, now creeping at 3-4 mm/yr, steps right to the Concord fault, which has a similar rate, 2.5-3.5 mm/yr, which is slightly slower than the 4.4 mm/yr rate on its northward continuation, the Green Valley fault. The Maacama fault creeps at 4.4 mm/yr near Ukiah and 6.5 mm/yr in Willits. The central and southern segments of the Calaveras fault are predominantly creeping, whereas the Hayward, Northern Calaveras, and Maacama faults are partly locked and, along with the Rodgers Creek and San Andreas, have high potential for major earthquakes.

  15. A record of estuarine water contamination from the Cd content of foraminiferal tests in San Francisco Bay, California

    USGS Publications Warehouse

    VanGeen, A.; Luoma, S.N.

    1999-01-01

    A five-year dissolved Cd time series from San Francisco Bay and adjacent coastal water shows that the composition of surface water towards the mouth of the estuary is determined largely by the effect of coastal upwelling. Cd concentrations inside and outside the estuary (0.2-1.0 nmol/kg) increase as Cd-rich deep water is advected to the surface near the coast during spring and summer. On average, the mean Cd concentrations inside San Francisco Bay (0.54 nmol/kg) during 1991-1995 was significantly higher than outside (0.35 nmol/kg), however. Surface samples collected throughout San Francisco Bay confirm an internal Cd source unrelated to river discharge. The Cd content of the test of a benthic foraminifer (Elphidiella hannai) in a dated sediment core from San Francisco Bay was measured to determine if the water column Cd enrichments in San Francisco Bay could be related to the rapid development of the watershed. The method is based on the observation that the Cd/Ca ratio of carefully cleaned tests of foraminifera is, determined by the dissolved Cd content of overlying water at the time of test formation. Pre-industrial foraminiferal Cd/Ca ratios in the sediment core average 274 ?? 15 nmol/mol (n = 19) nmol/mol. Foraminiferal Cd/Ca ratios increased to 386 ?? 33 nmol/mol (n = 19) over the past several decades indicating a 40% increase in the mean Cd content of surface water in Central San Francisco Bay. We suggest that, in addition to Cd discharges into the estuary, indirect consequences of agricultural development in the Central Valley of California could have contributed to this increase. This new method to reconstruct estuarine contamination is not affected by some of the processes that complicate the interpretation of changes in bulk sediment metal concentrations.

  16. Floc Depositional Characteristics within the Sacramento-San Joaquin River

    NASA Astrophysics Data System (ADS)

    Manning, Andrew; Schoellhamer, David

    2015-04-01

    The Sacramento-San Joaquin River Delta (Delta) is where the rivers of the Central Valley of California merge to become the San Francisco Estuary. The rivers deliver sediment from the Central Valley watershed (approximately 96,000 km2) to the Delta. One of the major drivers of sediment transport and turbidity in the Delta is the supply of fine sediment from the watersheds, particularly the Sacramento River. Deposited sediment helps create and sustain the landscape in the Delta, including desirable habitats such as tidal marsh, shoals, and floodplains. Massive sediment supply during the period of hydraulic mining in the late 1800s caused deposition in Sacramento Valley rivers, the Delta, and San Francisco Bay. Today, a key management question is whether the existing Delta landscape can be sustained as sea level rises. The erosion and deposition processes are strongly dependent on the local sediment properties, particularly when cohesion and flocculation are important, as they are in the Delta. The U.S. Geological Survey (USGS) collects data that supports the development, calibration, and validation of numerical models of sediment transport and turbidity in the Delta. Research questions include: How much flocculation of sediment particles occurs in the Delta, and what are the settling velocities of the flocs? How do floc settling properties vary spatially and temporally? To address these questions, a Co-operative Agreement was established between the USGS and HR Wallingford (UK). This abstract presents preliminary findings from measurements of floc depositional properties throughout the Delta during 2010-2011. Individual floc properties and dynamics were measured with the LabSFLOC-1 instrument; a high resolution video-based device. Thirty-one floc population samples were obtained from 21 sites within the Delta. Flocculated particles were observed throughout the Delta including in freshwater. Suspended-sediment concentrations in the near-bed region ranged from 4-52 mg

  17. Tectonic Setting of the LARSE 2 line, East Ventura and San Fernando Basins

    NASA Astrophysics Data System (ADS)

    Yeats, R. S.; Yeats, R. S.

    2001-12-01

    Middle Miocene tectonics was characterized by extension and volcanism, forming the NW-trending east Ventura rift, the Oak Ridge-Simi Hills horst, underlain by Cretaceous strata, a high granitic block in the central San Fernando Valley, a caldera complex in the western Santa Monica Mountains, and normal-faulted grabens in the Soledad Basin. Strike slip on the San Gabriel fault system (SGF) began in the middle Miocene with the Canton fault, the NE boundary of the east Ventura rift, extending into the San Fernando Basin as a possible precursor to the Verdugo fault. The SGF sensu stricto displaced the late Miocene Devil Canyon and Hasley submarine fans from their San Gabriel Mountains source, accompanied by formation of the Ridge Basin; most strike slip was completed by the Pliocene. Pliocene strata were deformed along the south-facing Pico and Newhall-Potrero monoclines and others masked by the younger Holser and Del Valle faults, extending into the hangingwall of the San Cayetano fault. The south-facing Torrey fault and north-facing Frew fault were precursors to the Quaternary Santa Susana (SSF) and Oak Ridge (ORF) faults, respectively. Active structures include the SSF, reactivating in the opposite sense the SW edge of the east Ventura rift. the blind ORF, source of the 1994 Northridge earthquake, the north-facing Holser and Del Valle faults, and the SGF, revitalized as an oblique-reverse fault. The SSF divides eastward into the Northridge Hills and Mission Hills faults, which merge eastward into the Verdugo fault, and the Sierra Madre fault at the north rim of the Sylmar Basin, together with the Buck Canyon, Lopez, and Kagel Ridge faults. The hangingwalls of these faults rotate clockwise, as does the hangingwall of the SSF, possibly in two segments bounded by the Gillibrand Canyon lateral ramp.

  18. Investigating Causes and Consequences of 150 Years of Channel Morphology Evolution in San Pablo Bay, California

    NASA Astrophysics Data System (ADS)

    Wegen, M. V.; Roelvink, J.; Jaffe, B. E.

    2010-12-01

    The Delta is an area where rivers draining the Central Valley and Sierras of California, including the Sacramento and San Joaquin Rivers, meet before discharging into the northeastern end of the San Francisco Estuary. San Pablo Bay, a sub-embayment in the northern Estuary, is circular with an area of about 250 km2 and an average tidal range of about 1.5 m. It is rather shallow (depths generally less than 4 m, average depth <2 m) and muddy apart from the main channel that transects the Bay from East to West conveying the river flow seaward. Bathymetric surveys from the 1850s to 1980s on a 30-year interval show that the morphology of San Pablo Bay has changed markedly since the Gold Rush. Deposition of more than a quarter billion cubic meters of hydraulic gold mining debris reduced the average depth of San Pablo Bay by 85 cm in the middle and late 1800s. In the late 1900s the intertidal flats narrowed and the major channel in the Bay deepened as more sediment was lost to the sea than entered from rivers. Processes of sediment redistribution caused the main channel to become narrower as well, a trend observed over the last 150 years. It is not clear what is causing the change in channel geometry and the implications of the change in geometry on the seaward transport of sediment through San Pablo Bay. This study investigates the cause of this channel geometry development and its impact on the conveyance of sediment through and distribution within San Pablo Bay using a process-based, numerical model (Delft3D). The Delft3D model developed for this study is a 3D model that includes the k-ɛ turbulence model, wind, waves, multiple mud and sand fractions and salt-fresh water density differences, as well as schematized tidal and river flow boundary conditions. The approach is to perform different runs with equal forcing on different historic bathymetries. By keeping the bed in a fixed, non-erodible state, we can analyze the impact of the evolving San Pablo Bay morphology on

  19. SRTM Perspective View with Landsat Overlay: San Joaquin Valley, California

    NASA Technical Reports Server (NTRS)

    2000-01-01

    San Joaquin, the name given to the southern portion of California's vast Central Valley, has been called the world's richest agricultural valley. In this perspective view generated using data from the Shuttle Radar Topography Mission and an enhanced Landsat image, we are looking toward the southwest over a checkerboard pattern of agricultural fields. Mt. Pinos, a popular location for stargazing at 2,692 meters (8,831 feet) looms above the valley floor and is visible on the left side of the image. The productive southern San Joaquin is in reality a desert, averaging less than 12.7 cm (5 inches) of rain per year. Through canals and irrigation, the region nurtures some two hundred crops including grapes, figs, apricots, oranges, and more than 4,047 square-km (1,000,000 acres) of cotton. The California Aqueduct, transporting water from the Sacramento River Delta through the San Joaquin, runs along the base of the low-lying Wheeler Ridge on the left side of the image. The valley is not all agriculture though. Kern County, near the valley's southern end, is the United States' number one oil producing county, and actually produces more crude oil than Oklahoma. For visualization purposes, topographic heights displayed in this image are exaggerated two times. Colors, from Landsat data, approximate natural color.

    The elevation data used in this image was acquired by 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 Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of Earth's land surface. To collect the 3-D SRTM data, engineers added a mast 60 meters (about 200 feet)long, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the NASA, the National Imagery and Mapping Agency (NIMA) of the U

  20. Exploring the Power Output of Small Wind Turbines in Urban San Antonio, Texas

    NASA Astrophysics Data System (ADS)

    Casillas, Jose; Sperduti, Stephanie; Cardenas, Rosa

    2015-03-01

    The means of transporting power from a centralized power plant by transmission lines has several disadvantages. Electricity transmission and distribution networks are costly, require long planning processes and are unsightly to residents. These networks are also susceptible to natural disasters creating massive disruptions to consumers. For these reasons distributed power sources such as solar panels and small wind turbines are becoming a more desirable and viable means of energy production. We report on the status of a study to determine the maximum output power of small wind turbines in urban San Antonio, Texas. Wind speed data along with power measurements from small wind turbines in urban San Antonio will be reported. U.S. Department of Education Title V HSI-STEM and Articulation Award No. P031C110145.