USGS Science⌕ Search

SEARCH · USGS Science

Results for “Progress Report”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,261 records · Page 70Linked to original sources

Interaction between ground water and surface water in the northern Everglades and relation to water budget and mercury cycling; study methods and appendixes

The data presented in this report are products of an investigation that quantified interactions between ground water and surface water at several study sites in the northern Everglades. Goals included identifying the major geologic controls and human alterations that affect interactions between ground water and surface water, and determining how those interactions affect mercury contamination. The primary study area was the 3,815-acre Everglades Nutrient Removal (ENR), a wetland constructed in the early 1990s as a prototype Stormwater Treatment Area (STA), to determine the effectiveness in removing excess nutrients from agricultural drainage. In order to ensure that results from ENR are broadly informative, work was also conducted in Water Conservation Area-2A (WCA-2A), a 105,000-acre basin surrounded by levees. In the past 50 years, WCA-2A has experienced extensive re- engineering of water flow, alterations in the pattern of water-level fluctuations and timing of fire frequency, as well as substantial ecological changes. The most visible ecological alteration is the change in dominance over the past 30 years from a sawgrass wetland to cattail wetland in the northeastern part of WCA-2A. The drastic change in vegetation in WCA-2A resulted at least in part from inputs of excess phosphorus from agricultural drainage. Substantial data collection programs were already in progress in both ENR and WCA- 2A when the present work began. The South Florida Water Management District (SFWMD) constructed the ENR project in 1994 to determine the effectiveness of constructed wetlands for water treatment. Measurements of surface water flow and water quality were made frequently in ENR between 1994 and 1998. Fewer ground water data were collected at ENR, and almost all of it was collected from shallow wells emplaced on perimeter levees. In contrast to the short-term nature of data collection in ENR, hydrologic and chemical data were collected over a much longer period in WCA-2A (since at least the mid- 1970s), but the number of sites and data- collection frequency is much less. Very little prior ground water data were available in WCA-2A. Given the availability of prior information, the present study emphasized the collection of ground water field data, particularly in the interior wetland areas of ENR and WCA- 2A. New wells were emplaced to permit the geologic, hydraulic, and chemical sampling that was needed to characterize interactions between surface water and ground water. In particular, lithology and hydraulic properties of the Surficial aquifer were determined, ground water flow paths and velocities were delineated, hydrologic fluxes between surface water and ground water were measured, and water budgets and surface- subsurface fluxes of mercury were determined. The purpose of this report is to compile under one cover all of the data collected in this investigation. In addition, the report contains a detailed description of the study methods and information about study sites, borehole drilling, well construction, seepage meter installation, and hydraulic and geochemical chemical sampling. Data interpretations are the subject of a companion report.

Florida↗

Quaternary stratigraphic sections with radiocarbon dates, Chandler Lake Quadrangle, Alaska

Twenty-eight organic samples from 17 localities in the Anaktuvuk, Tulunga, and Itkillik Valleys and at Shainin Lake range in age from more than 40,000 to about 1000 14C yr B.P. These dates, combined with fossil identifications and measured stratigraphic sections, provide significant insights into the history of glaciation, climatic change, and related events of late Quaternary time in the north-central Brooks Range. Two dates from Tulunga Valley show that peat-forming intervals during the middle Wisconsin and during an earlier period were terminated by episodes of loess accretion that probably correspond to glaciations in the Brooks Range. The Anayaknaurak Bluff exposure in Anaktuvuk Valley contains a weathered till of the Banded Mountain (Itkillik I) glaciation overlain by unweathered outwash gravel of Antler Valley (Itkillik II) age. Radiocarbon dates from finer alluvium above the outwash indicate that a subsequent glacial readvance north of the range front occurred shortly after 13,000 yr B.P. This event was synchronous with a major glacial readvance that culminated between about 12,900 and 12,700 yr B.P. farther east in the Atigun and Sagavanirktok Valleys. Additional dates from Anaktuvuk Valley show that glacier ice had retreated from the Antler Valley end-moraine complex by 10,600 yr B.P. The elongate basin that formed behind the moraine dam was being filled by alluvium at this time, and filling continued as late as 6200 yr B.P. near the range front. A possible climatic reversal during this interval is suggested by dates from Anaktuvuk Valley and from Toolik Valley farther east, which show peat formation between about 9500 and 8200 yr B.P. followed by solifluction and fan-building. Soil test pits and other excavations near Anaktuvuk Pass show that the pass was deglaciated some time prior to 7250 yr B.P., and was suitable for human habitation by at least 6500 yr B.P. Dated buried peat suggests a change to more severe frost climate sometime after about 4750 yr B.P. Other dates from the Chandler Lake quadrangle bear mainly on formation of low (generally 2.5 to 6 m) river terraces during intervals of renewed glaciation at valley heads during the late Holocene. Neoglaciation in the north-central Brooks Range evidently began about 3500 yr B.P., or at least was perceptible by this time as increased loess influx to sites north of the range front. Stream alluviation was in progress 2800-2700 yr B.P. at sites near Anaktuvuk Pass, and continued until sometime after 2000 yr B.P. Final phases of alluviation began about 1200 and 450 yr B.P. Independent dating of cirque-glacier advances by lichenometry supports the alluvial chronology and suggests that alluviation was controlled largely by increased sediment yield to streams during times of cirque-glacier expansion and increased rock-glacier activity.

Alaska↗

Historical and simulated changes in channel characteristics of the Kalamazoo River, Plainwell to Otsego, Michigan

In a study to understand the historical effects of the construction and decommissioning of dams on the Kalamazoo River, Plainwell to Otsego, Michigan, and to simulate channel changes that may result if the dams were removed, early to mid-1800s General Land Office surveys and aerial photographs from 1938, 1981, and 1999 were compared in order to identify historical changes in the river’s planform. This analysis of the 80-mile reach from Morrow Dam to the river mouth at Saugatuck provided insight into how susceptible the river has been to channel migration. The comparison showed that changes in channel width and location were caused mainly by construction of dams and subsequent water-level adjustments in the impounded reaches upstream from the dams. Braiding also occurred downstream from one of the dams. Minor changes in channel form that were not caused by the dams, such as the development and cutoff of meander bends, were observed. A more detailed study in a 5-mile reach passing through the Plainwell and Otsego City Dams included compiling existing valley cross section and longitudinal profile data into a database, assessing bank stability, and using a hydrologic model to simulate the channel as if the dams were removed. Fifty-four valley cross sections compiled from United States Geological Survey and consultant data sets were used as a base for a bank-stability assessment and to design a hypothetical stable channel without the two dams. The channel design involved adjusting the slope, hydraulic geometry, and floodplain width to ensure that water could be transferred through the reach without increasing flooding or erosion problems. The bank-stability assessment focused on conditions that are critical to failure. This was accomplished through the use of a two step process. The first involved evaluating the sediment removed from the bank toe when the stage is high. The second involved calculating the factor of safety for the bank based on the water table being elevated higher than the stage, mimicing a bank storage effect. Using these paired proccesses, two scenarios of critical conditions were evaluated: dams present and dams removed. Results of the bank assessments showed that, under both critical-condition scenarios, the streambanks were more susceptible to toe erosion than to block failure. As toe erosion progresses, the banks will eventually collapse as supporting material underneath is removed. Toe erosion for the damsremoved scenario resulted in higher amounts of erosion than for the dams-present scenario, leading to an overall decrease in bank stability. Effects of vegetation on the bank stability were variable; stability for some banks increase if vegetation was present but remain the same for other banks.

Michigan↗

Suspended sediment and trace element transport in the Big River downstream from the Old Lead Belt in southeastern Missouri, 2018–21

Lead Belt, an area of major lead mining from the 1860s until 1972 where more than 8.5 million tons of lead were mined. After active mining ceased, the effects of mining activities persisted in the Big River system because of large mine waste pile erosion, and floodplain sediment and streambank contamination along several tributaries and the main stem of the Big River. Lead-contaminated streambed and floodplain sediments extend more than 90 miles from the Old Lead Belt to the confluence of the Big River with the Meramec River. The waste piles and mine-waste contaminated streambed and floodplain sediments have been sources of high concentrations of several trace elements, primarily cadmium, lead, and zinc. The U.S. Environmental Protection Agency Region 7 has made several efforts to prevent further erosion of contaminated sediments into the Big River including the capping of major mine waste piles, reclaiming sediment deposits along the floodplains, and monitoring soil conditions of croplands and residential properties. A cooperative effort began in 2011 between the U.S. Geological Survey and the U.S. Environmental Protection Agency Region 7 to characterize suspended sediment quantity and quality in the Big River downstream from the Old Lead Belt as reclamation activities in the drainage basin progressed. The study was completed in two phases, and each phase included continuous stage, turbidity, and water temperature monitoring at the Big River below Bonne Terre, Missouri, streamgage and sampling station. Periodic suspended sediment samples also were collected manually (discrete samples) during base flow and selected stormflow events. Continuous streamflow, turbidity, and discrete suspended sediment data were used to develop regression models to compute daily suspended sediment concentrations and loads. During both phases, the discrete stormflow event samples were also evaluated to determine particle size distribution and concentrations of select trace elements. Phase one was completed from October 2011 through September 2013, and phase two, which is the primary focus of this report, was completed from October 2018 through September 2021. Phase two also included time-integrated suspended sediment samples collected using passive samplers. Discrete samples (collected during stormflow events) and passive samples were analyzed for concentrations of barium, cadmium, lead, and zinc in two sediment size fractions (when possible) to estimate trace element loads. Suspended sediment concentrations and loads and select trace element concentration results computed during phase one were compared to those computed during phase two to identify trends in the Big River Basin during the full study period. The concentrations of cadmium, lead, and zinc in nearly all discrete stormflow event suspended sediment samples and passive suspended sediment samples exceeded the threshold effect concentrations and the probable effect concentrations, which are two sediment quality guidelines. Most samples also exceeded the toxic effect threshold, the level at which sediment is considered to be heavily contaminated and problematic for sediment-dwelling organisms. Bulk cadmium concentrations (median of 7.90 milligrams per kilogram [mg/kg]) exceeded the toxic effect threshold (3.0 mg/kg) in 17 discrete stormflow event samples, and bulk lead concentrations (median of 1,070 mg/kg) exceeded the toxic effect threshold (170 mg/kg) in all 18 discrete stormflow event samples. Bulk zinc concentrations (median of 500 mg/kg) exceeded the toxic effect threshold (540 mg/kg) in eight discrete stormflow event samples. Bulk concentrations of these trace elements in passive suspended sediment samples were slightly greater, with concentrations of cadmium (median of 14.0 mg/kg) and lead (median of 1,860 mg/kg) exceeding the toxic effect threshold in all 18 samples. Bulk concentrations of zinc (median of 733 mg/kg) exceeded the toxic effect threshold in 15 passive samples. Compared to phase one (water years 2012–13), phase two (water years 2019–21) concentrations of lead and cadmium in the fine fraction of discrete suspended sediment samples collected at Big River below Bonne Terre were statistically similar; concentrations of barium and zinc were statistically smaller in samples collected during phase two (water years 2018–21). Sediment quality data from passive samples and daily mean suspended sediment loads from the regression model were used to calculate annual oads of barium, cadmium, lead, and zinc at the Bonne Terre streamgage. Water year 2019 had the largest loads of barium, cadmium, lead, and zinc (58.6, 1.43, 194, and 76.5 tons, respectively). The total loads of barium, cadmium, lead, and zinc for phase two (water years 2019–21) were 149, 4.00, 520, and 213 tons, respectively. Less than 5 percent of the total lead load calculated for the study period was transported when daily mean streamflow was less than 455 cubic feet per second, which is the approximate flow at which the passive samplers were inundated and began sampling. This highlights that most of the lead load is transported during stormflow events and the effectiveness of using passive samplers for ongoing monitoring of the Big River. Annual suspended sediment loads at the Bonne Terre streamgage computed using the regression model were 113,000 tons in water year 2019, 83,400 tons in water year 2020, and 96,500 tons in water year 2021. The event-based suspended sediment loads for the eight sampled stormflow events ranged from 45.3 to 32,500 tons. Although only a portion of all stormflow events during phase two were sampled, the loads accounted for during these eight stormflow events represented approximately 30.9 percent of the total suspended sediment load calculated for the study period, confirming that a large part of suspended sediments continue to be transported in the Big River during stormflow events. Event-based loads of barium, cadmium, lead, and zinc were greatest during the stormflow events sampled in January 2020 (event 4) and March 2021 (event 8). Event-based loads calculated for event 4 for barium, cadmium, lead, and zinc were 17.1, 0.206, 27.2, and 14.5 tons, respectively. During event 8, an estimated 15.6 tons of barium, 0.239 tons of cadmium, 34.0 tons of lead, and 13.6 tons of zinc were transported in suspended sediments. The continued high concentrations of lead in suspended sediments in the Big River, despite reclamation activities, is likely because of the continual transport from streambed and stream banks of lead-enriched sediment, which remain in the system from historical mining activities.

Missouri↗

Quantifying seascape structure: Extending terrestrial spatial pattern metrics to the marine realm

Spatial pattern metrics have routinely been applied to characterize and quantify structural features of terrestrial landscapes and have demonstrated great utility in landscape ecology and conservation planning. The important role of spatial structure in ecology and management is now commonly recognized, and recent advances in marine remote sensing technology have facilitated the application of spatial pattern metrics to the marine environment. However, it is not yet clear whether concepts, metrics, and statistical techniques developed for terrestrial ecosystems are relevant for marine species and seascapes. To address this gap in our knowledge, we reviewed, synthesized, and evaluated the utility and application of spatial pattern metrics in the marine science literature over the past 30 yr (1980 to 2010). In total, 23 studies characterized seascape structure, of which 17 quantified spatial patterns using a 2-dimensional patch-mosaic model and 5 used a continuously varying 3-dimensional surface model. Most seascape studies followed terrestrial-based studies in their search for ecological patterns and applied or modified existing metrics. Only 1 truly unique metric was found (hydrodynamic aperture applied to Pacific atolls). While there are still relatively few studies using spatial pattern metrics in the marine environment, they have suffered from similar misuse as reported for terrestrial studies, such as the lack of a priori considerations or the problem of collinearity between metrics. Spatial pattern metrics offer great potential for ecological research and environmental management in marine systems, and future studies should focus on (1) the dynamic boundary between the land and sea; (2) quantifying 3-dimensional spatial patterns; and (3) assessing and monitoring seascape change.

Marine Ecology Progress Series↗

Hydrologic data for urban studies in the Houston, Texas, metropolitan area, 1982

Hydrologic investigations of urban watersheds in Texas were begun by the U.S. Geological Survey in 1954. Studies are now in progress in Austin, and Houston. Studies have been completed in the Dallas-Fort Worth and San Antonio areas. The U.S. Geological Survey, in cooperation with the city of Houston, began studies in the Houston metropolitan area in 1964. The program was expanded in 1968 to include collection of water-quality data. The objectives of the Houston urban-hydrology study are as follows: To determine, on the basis of historical data and hydrologic analyses, the magnitude and frequency of flood peaks and flood volumes. To determine the effect of urban development on flood peaks and volumes. To ascertain the variation in water quality for different flow conditions and different seasons. This report, the nineteenth in a series of reports to be published annually, is primarily applicable to objective 2. The report presents hydrologic data collected in the Houston urban area for the 1982 water year (October 1, 1981 to September 30, 1982). A report by Johnson and Sayre (1973) utilized records collected from 1965 to 1969 to study the effects of urbanization on floods in the Houston area. The report also summarizes various basin parameters. A report by Waddell, Massey, and Jennings (1979) presents data on runoff from the Houston area and computed concentrations and loads of selected water-quality constituents discharged to Galveston Bay. The study utilized a variation of the "STORM" model developed by the Hydrologic Engineering Center of the U.S. Army Corps of Engineers. A report prepared by Li scum and Massey (1980) presents a technique for estimating the magnitude and frequency of floods in the Houston area from drainage areas, bank-full conveyance, and percentage of urban development. A definition of terms related to streamflow, water quality, and other hydrologic data, as used in this report, are defined in "U.S. Geological Survey, Water-resources data for Texas, water year 1982, volume 2." To facilitate the publication and distribution of this report some material has been included that does not conform to the formal publications standards of the U.S. Geological Survey.

Texas↗

Hydrologic data for urban studies in the Houston, Texas, metropolitan area, 1981

Hydro! oqic investigations of urban watersheds in Texas were begun by the U.S. Geological Survey in 1954. Studies are now in progress in Austin, and Houston. Studies have been completed in the Dallas-Fort Worth and San Antonio areas. The U.S. Geological Survey, in cooperation with the city of Houston, began studies in the Houston metropolitan area in 1964. The program was expanded in 1968 to include collection of water-quality data. The objectives of the Houston urban-hydrology study are as follows: To determine, on the basis of historical data and hydro!ogic analyses, the magnitude and frequency of flood peaks and flood volumes. To determine the effect of urban development on flood peaks and volumes. To ascertain the variation in water quality for different flow conditions and different seasons. This report, the eighteenth in a series of reports to be published annually, is primarily applicable to objective 2. The report presents hydro!ogic data collected in the Houston urban area for the 1981 water year (October 1, 1980 to September 30, 1981).

Texas↗

Final Report: Five years of monitoring reconstructed freshwater tidal wetlands in the urban Anacostia River (2000-2004)

The Anacostia River in Washington, D.C. USA consisted of over 809 hectares (2000 acres) of freshwater tidal wetlands before mandatory dredging removed most of them in the first half of the 20th century. Much of this13 kilometer (8 mile) reach was transferred to the National Park Service (NPS). Planning processes in the 1980?s envisioned a restoration (rejuvenation) of some wetlands for habitat, aesthetics, water quality and interpretative purposes. Subsequently, the U.S. Army Corps of Engineers in a cost share agreement with the District of Columbia reconstructed wetlands on NPS lands at Kenilworth - 12.5 hectares (1993), Kingman - 27 hectares (2000), a Fringe Marsh - 6.5 hectares (2003) and is currently constructing Heritage Marsh - 2.5 hectares (2005/2006). The USGS Patuxent Wildlife Research Center in conjunction with the University of Maryland Biological Engineering Department was contracted to conduct post-reconstruction monitoring (2000-2004) to document the relative success and progress of the Kingman Marsh reconstruction primarily based on vegetative response but also in conjunction with seed bank and soil characteristics. Results from Kingman were compared to Kenilworth Marsh (reconstructed 7 years prior), Dueling Creek Marsh (last best remaining freshwater tidal wetland bench in the urbanized Anacostia watershed) and Patuxent River Marsh (in a more natural adjacent watershed). Vegetation establishment was initially strong at Kingman, but declined rapidly as measured by cover, richness, diversity , etc. under grazing pressure from resident Canada geese and associated reduction in sediment levels. This decline did not occur at the other wetlands. The decline occurred despite a substantial seed bank that was sustained primarily be water born propagules. Soil development, as true for most juvenile wetlands, was slow with almost no organic matter accumulation. By 2004 only two of 7 planted species remained (mostly Peltandra virginica) at Kingman which did provide almost 50% of the approximately 1/3 total vegetation cover remaining.

Book↗

Hydrologic data for urban studies in the Houston metropolitan area, Texas, 1983

Hydro!ogic investigations of urban watersheds in Texas were begun by the U.S. Geological Survey in 1954. Studies are now in progress in the Austin and Houston areas, and have been completed in the Dallas-Fort Worth and San Antonio areas. The U.S. Geological Survey, in cooperation with the city of Houston, began studies in the Houston metropolitan area in 1964. The program was expanded in 1968 to include collection of water-quality data. The objectives of the Houston urban-hydrology study are as follows: To determine, on the basis of historical data and hydrologic analyses, the magnitude and frequency of flood peaks and flood volumes. To determine the effect of urban development on flood peaks and volumes. To ascertain the variation in water quality for different flow conditions and different seasons. This report, the twentieth in a series of reports to be published annually, is primarily applicable to objective No. 2. The report presents hydrologic data collected in the Houston urban area for the 1983 water year (October 1, 1982, to September 30, 1983). A report by Johnson and Sayre (1973) utilized records collected from 1965 to 1969 to study the effects of urbanization on floods in the Houston area. That report also summarized various basin parameters. A report by Waddell, Massey, and Jennings (1979) presented data on runoff from the Houston area and computed concentrations and loads of selected water-quality constituents discharged to Galveston Bay. The study utilized a variation of the "STORM" model developed by the Hydrologic Engineering Center of the U.S. Army Corps of Engineers. A report prepared by Li scum and Massey (1980) presented a technique for estimating the magnitude and frequency of floods in the Houston area from drainage areas, bank-full conveyance, and percentage )f urban development. A definition of terms related to streamflow, water quality, and other hydrologic data, as used in this report, are defined in " U.S. Geological Survey, Water-resources data for Texas, water year 1983, volume 2."

Texas↗

The 3D Elevation Program—Supporting New Mexico’s Economy

Introduction Federal, State, Tribal, and local entities managing lands in New Mexico have concerns about wildfire risk, wildlife habitat, and flood risk. Land managers in urban areas along the Rio Grande corridor and in the State’s rural northwest and southeast also have concerns about existing and developing roads, buildings, and other infrastructure. Federal, State, Tribal, and local organizations actively manage and monitor New Mexico’s water resources. Critical applications that meet the State’s management needs depend on light detection and ranging (lidar) data that provide a highly detailed three-dimensional (3D) model of the Earth’s surface and aboveground features. The 3D Elevation Program (3DEP) is managed by the U.S. Geological Survey in partnership with Federal, State, Tribal, U.S. territorial, and local agencies to acquire consistent lidar coverage at quality level 2 or better to meet the many needs of the Nation and New Mexico. The status of available and in-progress 3DEP baseline lidar data in New Mexico is shown. 3DEP baseline lidar data include quality level 2 or better, 1-meter or better digital elevation models, and lidar point clouds, and must meet the Lidar Base Specification version 1.2 or newer requirements. The National Enhanced Elevation Assessment identified user requirements and conservatively estimated that availability of lidar data would result in at least $9.32 million in new benefits annually to the State.

New Mexico↗

Time-domain electromagnetic surveys at Fort Irwin, San Bernardino County, California, 2010–12

Between 2010 and 2012, a total of 79 time-domain electromagnetic (TEM) soundings were collected in 12 groundwater basins in the U.S. Army Fort Irwin National Training Center (NTC) study area to help improve the understanding of the hydrogeology of the NTC. The TEM data are discussed in this chapter in the context of geologic observations of the study area, the details of which are provided in the other chapters of this volume. Selection of locations for TEM soundings in unexplored basins was guided by gravity data that estimated depth to pre-Tertiary basement complex of crystalline rock and alluvial thickness. Some TEM data were collected near boreholes with geophysical logs. The TEM response at locations near boreholes was used to evaluate sounding data for areas without boreholes. TEM models also were used to guide site selection of subsequent boreholes drilled as part of this study. Following borehole completion, geophysical logs were used to ground-truth and reinterpret previously collected TEM data. This iterative process was used to site subsequent TEM soundings and borehole locations as the study progressed. Although each groundwater subbasin within the NTC boundaries was explored using the TEM method, collection of TEM data was focused in those basins identified as best suited for development of water resources. At the NTC, TEM estimates of some lithologic thicknesses and electrical properties in the unsaturated zone are in good accordance with borehole data; however, water-table elevations were not easily identifiable from TEM data.

California↗

Changes in the lake trout population of southern Lake Superior in relation to the fishery, the sea lamprey, and stocking, 1950-70

Commercial catch and effort statistics for 1929-70, samples of commercial catches in 1959-62, and records of examinations of all lake trout (Salvelinus namaycush) taken commercially in inshore waters of Michigan and Wisconsin in 1962-70 were the basis for descriptions of changes in the population in 1929-70. Abundance fluctuated cyclically and gradually downward in 1929-49, whereas fishing intensity tended to increase during the same period. In 1950-52, a change from cotton to nylon twine in gillnets raised effective fishing effort to 305% of the 1929-43 average in Michigan waters and to 228% in Wisconsin waters; production held near average. Abundance fell to 18% of average in Michigan in 1953-61 and to 25% of average in Wisconsin in 1956-61; in the same periods, production fell to 11% of average in Michigan and to 19% in Wisconsin. In 1962-70 abundance rose to 160% in Michigan and 246% in Wisconsin while production and fishing intensity were held low (3-14%) by regulation. Changes in abundance of lake trout were attributable to a sequence of developments in successive series of years; intensive fishing in the early 1950's; severe sea lamprey predation in the late 1950's; an 85% reduction in abundance of sea lampreys in mid 1961; and the combination of sea lamprey control, intensive stocking of yearling lake trout, and restrictions on fishing in 1962-70. A decline in average size of lake trout and the near elimination of spawning stocks in 1953-61 curtailed recruitment of native lake trout in the mid 1960's. Stocking of fin-clipped lake trout replaced natural reproduction in the early 1960's. In 1965-70, the lake trout population was composed mainly of hatchery-reared fish. Natural reproduction was reestablished on one major spawning shoal in Wisconsin in 1965, but in 1970 only 10% of the legal (17-inch and longer) and 17% of the undersize lake trout in Wisconsin were native fish. Reduction of sea lamprey abundance resulted in an immediate increase in survival and abundance of lake trout, especially of the larger sizes. As abundance of lake trout progressively increased in 1962-70, survival of the smaller legal-size lake trout increased, probably due to reduction of the predator-prey ratio and an increase in availability of larger lake trout preferred by sea lampreys. Abundance of spawning-size lake trout was limited by high natural mortality in 1965-70. Circumstantial evidence suggested that sea lamprey predation contributed a major part of the high natural mortality.

Technical Report↗

Hydrologic data for urban studies in the Houston metropolitan area, Texas, 1984

Hydrologic investigations of urban watersheds in Texas were begun by the U.S. Geological Survey in 1954. Studies are now in progress in the Austin and Houston areas, and have been completed in the Dallas-Fort Worth and San Antonio areas. The U.S. Geological Survey, in cooperation with the city of Houston, began studies in the Houston metropolitan area in 1964. The program was expanded in 1968 to include collection of water-quality data. The objectives of the Houston urban-hydrology study are as follows: To determine, on the basis of historical data and hydrologic analyses, the magnitude and frequency of flood peaks and flood volumes; To determine the effect of urban development on flood peaks and volumes; and To ascertain the variation in water quality for different flow conditions and different seasons. This report, the twenty-first and last scheduled in a series of reports published annually, is primarily applicable to objective 2. The report presents hydrologic data collected in the Houston urban area for the 1984 water year (October 1, 1983 to September 30, 1984). A report by Johnson and Sayre (1973) utilized records collected from 1965 to 1969 to study the effects of urbanization on floods in the Houston area. That report also summarized various basin parameters. A report by Waddell, Massey, and Jennings (1979) presented data on runoff from the Houston area and computed concentrations and loads of selected water-quality constituents discharged to Galveston Bay. The study utilized a variation of the "STORM" model developed by the Hydrologic Engineering Center of the U.S. Army Corps of Engineers. A report prepared by Liscum and Massey (1980) presented a technique for estimating the magnitude and frequency of floods in the Houston area from drainage areas, bank-full conveyance, and percentage of urban development. A definition of terms related to streamflow, water quality, and other hydrologic data, as used in this report, are defined in "U.S. Geological Survey, Water-resources data for Texas, water year 1984, volume 2."

Texas↗

Metallogenic provinces of the southeastern Pacific region

Metalliferous mineral deposits of the southeastern Pacific region include: (1) hydrothermal, magmatic, and sedimentary deposits of the Andean region, one of the great mineral belts of the world; 2) Scattered hydrothermal mineral occurrences in the Antarctic Peninsula; and 3) metal-enriched pelagic sediments, ferromanganese nodules, and volcanic rocks(?) in the southeast Pacific basin. Andean metalliferous deposits, the chief concern of this report, are for the most part spatially and genetically related to calc-alkaline plutons, sub-volcanic intrusions, and volcanic rocks emplaced during the Andean orogeny of Late Triassic to Quaternary age. These deposits are components of a single metallogenic province superimposed on two or more pre-Andean metallogenic provinces that are indicated by scattered deposits of Paleozoic and Precambrian(?) age. Occurrences in the Antarctic Peninsula are of age and origin similar to the deposits in the Andes and are considered to belong to the Andean province. The Andean metallogenic province may be divided into several subprovinces, each parallel to the Andes and the continental margin and each having a dominant metal or suite of metals. The central Andes of Peru, northern Chile, and Bolivia, which contain the greatest concentration of exploitable deposits and the greatest variety of ore types, have as many as five linear partly overlapping subprovinces. These sub-provinces, from west to east (Pacific coast to the eastern Andean front), are characterized, respectively, by deposits of : 1) iron; 2) copper, with or without associated gold; 3) polymetallic base metals (zinc, lead, copper), generally containing silver; 4) tin; and 5) gold. Iron deposits chiefly are near the coast in central to northern Chile and in southern Peru. The copper and polymetallic provinces are characterized by abundant deposits in the central Andean region but comparatively few scattered deposits in the north (Ecuador, Colombia, and Venezuela) and in southern Chile and Argentina. Scattered gold-rich veins and placers occur along the western Andean front and coastal region, the general area of the copper province, from central Chile to northern Colombia. Similar deposits occur along a discontinuous belt in the eastern Andes from Bolivia to Ecuador and in the central Andes of Colombia. Tin deposits are almost wholly restricted to the eastern Andes of Bolivia. The position and age distribution of plutonic and volcanic rocks and associated metalliferous deposits of the Andes indicate presence of an active subduction zone in this region since at least Late Triassic time. Magmas of the calc-alkaline igneous rocks are believed to have formed chiefly by partial melting of mantle, oceanic sediments, and oceanic crust along the Benioff zone at depths of 100 to 200 km. Plutonic and volcanic rocks show a general though nonuniform progression of decreasing age from west to east. Rocks of Jurassic and Cretaceous age are most abundant near the coast, whereas those of Tertiary and Quaternary age dominate in the Andes. Locally, intrusive rocks and ore deposits of widely different ages are juxtaposed. Metals of the ore deposits associated with the calc-alkaline rocks were supplied by the source rocks in the Benioff zone, some of which probably had been previously enriched in certain metals at the ancestral East Pacific Rise and were mobilized or assimilated from metal-rich zones in the overlying mantle and continental crust by magmas rising from the Benioff zone.

Open-File Report↗

Influence of climate on progressive hillslope failure in Redwood Creek Valley, northwestern California

Both creep and earthflow processes control hillslope erosion over large parts of the Redwood Creek basin. The type of process and displacement rates are largely dependent on underlying bedrock type and precipitation input. Progressive creep with rates ranging from 1.0 to 2.5 mm/a dominates on slopes west of the Grogen fault underlain by sheared and foliated schists. Movement appears to respond primarily to annual increments of precipitation. Complex earthflows occur predominantly on slopes east of the Grogen fault underlain by sheared graywacke and mudstone. Movement rates range from 3.0 to 131.0 mm/a and characteristically display dominant rainy season movement.

Open-File Report↗

Reconnaissance geology of the Harrat Hutaymah Quadrangle, sheet 26/42A, Kingdom of Saudi Arabia

Harrat Hutaymah quadrangle is underlain mostly by Proterozoic rocks that are intruded and partly covered in the north by the Quaternary extrusive products of the Harrat Hutaymah basalt field. The Proterozoic basement of the quadrangle may be broadly divided into the older (circa 650 Ma and older) Laban dioritic complex in the east and the younger (to possibly coeval) Kilab monzogranite batholith in the west. The dioritic complex is overlain by a monoclinal section of mostly intermediate composition volcanic and sedimentary rocks in the southeast (the Hibshi formation - dated at circa 632 Ma). The source plutons for the Hibshi volcanic rocks are not well constrained; the volcanics may be comagmatic with late phases of the Kilab batholith. All of these rocks are intruded by a younger (post-orogenic and circa 600 Ma) suite of more evolved granitic plutons and dikes. Several of these evolved granites may represent the root-zones of volcanic caldera complexes. The Hibshi formation is divided into several members that are described in detail based on data from measured sections at the type section (Jibal Hibshi). There is considerable variation in composition and facies within the formation; individual members thicken and thin laterally, and some pinch out entirely over distances of only a few kilometers. Volcanic members at Jabal Hibshi are mostly andesitic to dacitic pyroclastic rocks, but at Jabal Aba al Liqah, basaltic and rhyolitic flow rocks predominate. The Hibshi formation consists of clastic sediments of volcanic and plutonic provenance intertonguing with the varied products of multiple subaerial volcanic centers. For these reasons, regional correlation based only on lithology is discouraged. The Harrat Hutaymah basalt field contains abundant basaltic tephra as well as alkali olivine basalt flows. Tuff rings formed by explosive eruptions above mantle diatremes. Peridotite nodules are common in the basaltic tuff and in some flow rocks. Basaltic volcanism in the region began at a later time (circa 1.8 Ma) than at the other Saudi Arabian harrats; probably due to progressive mantle underflow related to Red Sea rifting. Areas having mineral resource potential include the ancient Samirah gold mine, a quartz-vein deposit in Laban complex dioritic rocks, and areas with tin-tungsten potential in the evolved plutons. Aggregate and pozzolan deposits occur in the basaltic tephra of the Harrat Hutaymah volcanic field and unusually deep groundwater reservoirs are present in the filled tuff-ring craters of the volcanic field.

Open-File Report↗

Biological review of 82 species of coral petitioned to be included in the Endangered Species Act

list 83 coral species as threatened or endangered under the U.S. Endangered Species Act. The petition was based on a predicted decline in available habitat for the species, citing anthropogenic climate change and ocean acidification as the lead factors among the various stressors responsible for the potential decline. The NMFS identified 82 of the corals as candidate species, finding that the petition provided substantive information for a potential listing of these species. The NMFS established a Biological Review Team (BRT) to prepare this Status Review Report that examines the status of these 82 candidate coral species and evaluates extinction risk for each of them. This document makes no recommendations for listing, as that is a separate evaluation to be conducted by the NMFS. The BRT considered two major factors in conducting this review. The first factor was the interaction of natural phenomena and anthropogenic stressors that could potentially contribute to coral extinction. After extensive review of available scientific information, the BRT considers ocean warming, disease, and ocean acidification to be the most influential threats in posing extinction risks to the 82 candidate coral species between now and the year 2100. Threats of local origin but having widespread impact, such as sedimentation, nutrient enrichment, and fishing, were considered of medium importance in determining extinction risks. It is acknowledged that many other threats (e.g., physical damage from storms or ship groundings, invasive species or predator outbreaks, collection and trade) also negatively affect corals, often acutely and dramatically, but generally at relatively small local scales. These local threats were considered to be of limited scope and not deemed to contribute appreciably to the risk of species extinction, except in those special cases where species have restricted geographic or habitat ranges or species have already undergone precipitous population declines such that these local threats further contribute to depensatory processes that can magnify extinction risks (e.g., feedback-loops whereby individual survival decreases with smaller population size). The BRT acknowledges that local and global threats operate on different time scales and, though there is high confidence in the general progression of some key global threats, such as ocean warming and ocean acidification, there is much less certainty in the timing and spatial patterns of these threats. There is also substantial uncertainty in the abilities of the 82 candidate coral species to tolerate or adapt to each of the threats examined, as well as uncertainty in the dynamics of multiple simultaneous stresses. The BRT specifically identified increasing human population levels and the intensity of their collective human consumption as the root drivers of almost all global and local threats to coral species. In evaluating future threat impacts, the BRT attempted to project current trends, without assumptions of future policy changes or technological advances that could potentially alter the projections used in this analysis.

NOAA Technical Memorandum↗

Water-quality modeling of Klamath Straits Drain recirculation, a Klamath River wetland, and 2011 conditions for the Link River to Keno Dam reach of the Klamath River, Oregon

The upper Klamath River and adjacent Lost River are interconnected basins in south-central Oregon and northern California. Both basins have impaired water quality with Total Maximum Daily Loads (TMDLs) in progress or approved. In cooperation with the Bureau of Reclamation, the U.S. Geological Survey (USGS) and Watercourse Engineering, Inc., have conducted modeling and research to inform management of these basins for multiple purposes, including agriculture, endangered species protection, wildlife refuges, and adjacent and downstream water users. A water-quality and hydrodynamic model (CE-QUAL-W2) of the Link River to Keno Dam reach of the Klamath River for 2006–09 is one of the tools used in this work. The model can simulate stage, flow, water velocity, ice cover, water temperature, specific conductance, suspended sediment, nutrients, organic matter in bed sediment and the water column, three algal groups, three macrophyte groups, dissolved oxygen, and pH. This report documents two model scenarios and a test of the existing model applied to year 2011, which had exceptional water quality. The first scenario examined the water-quality effects of recirculating Klamath Straits Drain flows into the Ady Canal, to conserve water and to decrease flows from the Klamath Straits Drain to the Klamath River. The second scenario explicitly incorporated a 2.73×10 6 m 2 (675 acre) off-channel connected wetland into the CE-QUAL-W2 framework, with the wetland operating from May 1 through October 31. The wetland represented a managed treatment feature to decrease organic matter loads and process nutrients. Finally, the summer of 2011 showed substantially higher dissolved-oxygen concentrations in the Link-Keno reach than in other recent years, so the Link-Keno model (originally developed for 2006–09) was run with 2011 data as a test of model parameters and rates and to develop insights regarding the reasons for the improved water-quality conditions.

Oregon↗