Water-quality assessment of the Connecticut, Housatonic, and Thames River Basins study unit: Analysis of available data on nutrients, suspended sediments, and pesticides, 1972-92
Marc J. Zimmerman, Stephen J. Grady, Elaine C. Todd Trench, Sarah M. Flanagan, Martha G. Nielson
1996, Water-Resources Investigations Report 95-4203
This retrospective report examines available nutrient, suspended sediment, and pesticide data in surface and ground water in the Connecticut, Housatonic and Thames Rivers Study Unit of the National Water-Quality Assessment Program. The purpose of this study is to improve the understanding of natural and anthropogenic factors affecting water quality in...
Geohydrology of the shallow aquifers in the Denver metropolitan area, Colorado
Stanley G. Robson
1996, Hydrologic Atlas 736
The Denver metropolitan area is underlain by shallow layers of water-bearing sediments (aquifers) consisting of unconsolidated gravel, sand, silt, and clay. The depth to water in these aquifers is less than 20 feet in much of the area, and the aquifers provide a ready source of water to numerous shallow,...
Earthquakes and the southeastern boundary of the intact Iapetan margin in eastern North America
R. L. Wheeler
1996, Seismological Research Letters (67) 77-83
Earthquakes at three localities in eastern North America have been attributed on geological and seismological grounds to compressional reactivation of some of the late Proterozoic or early Paleozoic normal faults in the northeast-trending Iapetan passive margin. Assessment of seismic hazard can be aided by identifying the boundaries of the area...
Axial structures within the Reelfoot Rift delineated with magnetotelluric surveys
B. D. Rodriguez, W. D. Stanley, J. M. Williams
1996, Professional Paper 1538-K
In the winter of 1811-12, three of the largest historic earthquakes in the United States occurred near New Madrid, Mo. Seismicity continues to the present day throughout a tightly clustered pattern of epicenters centered on the bootheel of Missouri, including parts of northeastern Arkansas, northwestern Tennessee, western Kentucky, and southern...
Temporal changes in the configuration of the water table in the vicinity of the management systems evaluation area site, central Nebraska
John M. Kilpatrick
1996, Water-Resources Investigations Report 94-4173
To improve understanding of the hydrologic characteristics of the shallow aquifer in the vicinity of the Management Systems Evaluation Area site near Shelton, Nebraska, water levels were measured in approximately 130 observation wells in both June and September 1991. Two water-table maps and a water-level-change map were drawn on the...
Geohydrology and contamination at the Michigan Department of Transportation maintenance garage area, Kalamazoo County, Michigan
E. A. Lynch, G.C. Huffman
1996, Water-Resources Investigations Report 96-4010
A leaking underground storage tank was removed from the Michigan Department of Transportation maintenance garage area in Kalamazoo County., Mich., in 1985. The tank had been leaking unleaded gasoline. Although a remediation system was operational at the site for several years after the tank was removed, ground-water samples collected from...
Hydrogeologic framework of the North Carolina coastal plain
M. D. Winner Jr., R. W. Coble
1996, Professional Paper 1404-I
The hydrogeologic framework of the North Carolina Coastal Plain aquifer system consists of 10 aquifers separated by 9 confining units. From top to bottom, the aquifers are the surficial aquifer, Yorktown aquifer, Pungo River aquifer, Castle Hayne aquifer, Beaufort aquifer, Peedee aquifer, Black Creek aquifer, upper Cape Fear aquifer, lower...
Hydrology of the Wolf Branch sinkhole basin, Lake County, east-central Florida
D. M. Schiffer
1996, Open-File Report 96-143
A 4-year study of the hydrology of the Wolf Branch sinkhole basin in Lake County, Florida, was conducted from 1991-95 by the U.S. Geological Survey to provide information about the hydrologic characteristics of the drainage basin in the vicinity of Wolf Sink. Wolf Branch drains a 4.94 square mile area...
Hazards and climatic impact of subduction‐zone volcanism: A global and historical perspective
Robert I. Tilling
1996, Book chapter, Subduction: Top to Bottom
Subduction-zone volcanoes account for more than 80 percent of the documented eruptions in recorded history, even though volcanism--deep and, hence, unobserved--along the global oceanic ridge systems overwhelmingly dominates in eruptive output. Because subduction-zone eruptions can be highly explosive, they pose some of the greatest natural hazards to society if the...
Floods, runoff, and snowpack in Utah, 1995
D.V. Allen
1996, Fact Sheet 106-96
Utah, like other States in the western United States, has experienced several rapid and extreme changes between wet and dry precipitation cycles during recent years. During the 1995 water year (October 1994 to September 1995), most areas of Utah experienced greater-than-normal precipitation (1961-90), which was reflected in greater-than-average snowpack, moderate...
Hydrology of the Mississippi River valley alluvial aquifer, south-central United States
D. J. Ackerman
1996, Professional Paper 1416-D
Ground-water flow simulation indicates that pumpage from the aquifer since the early 1900's has caused a decrease in ground-water outflow to rivers, an increase in flow from rivers into the aquifer, and an increase in flow to the aquifer through the overlying confining unit. By the mid-1970's, rivers became a...
Summary of the Snake River plain Regional Aquifer-System Analysis in Idaho and eastern Oregon
G. F. Lindholm
1996, Professional Paper 1408-A
Regional aquifers underlying the 15,600-square-mile Snake River Plain in southern Idaho and eastern Oregon was studied as part of the U.S. Geological Survey's Regional Aquifer-System Analysis program. The largest and most productive aquifers in the Snake River Plain are composed of Quaternary basalt of the Snake River Group, which underlies...
Chemical evaluation of soil-solution in acid forest soils
G.B. Lawrence, Mark B. David
1996, Soil Science (161) 298-313
Soil-solution chemistry is commonly studied in forests through the use of soil lysimeters.This approach is impractical for regional survey studies, however, because lysimeter installation and operation is expensive and time consuming. To address these problems, a new technique was developed to compare soil-solution chemistry among red spruce stands in New...
Crustal and upper mantle velocity structure of the Salton Trough, southeast California
T. Parsons, J. McCarthy
1996, Tectonics (15) 456-471
This paper presents data and modelling results from a crustal and upper mantle wide-angle seismic transect across the Salton Trough region in southeast California. The Salton Trough is a unique part of the Basin and Range province where mid-ocean ridge/transform spreading in the Gulf of California has evolved northward into...
Far-travelled Permian chert of the North Fork terrane, Klamath Mountains, California
Edward A. Mankinen, W. P. Irwin, C.D. Blome
1996, Tectonics (15) 314-328
Permian chert in the North Fork terrane and correlative rocks of the Klamath Mountains province has a remanent magnetization that is prefolding and presumably primary. Paleomagnetic results indicate that the chert formed at a paleolatitude of 8.6° ± 2.5° but in which hemisphere remains uncertain. This finding requires that these...
Hydrogeologic framework of the Great Basin region of Nevada, Utah, and adjacent states
R. W. Plume
1996, Professional Paper 1409-B
Regional aquifer systems in the Great Basin consist of carbonate-rock aquifers in the eastern Great Basin and basin-fill aquifers throughout the region. In the carbonate-rock aquifers, barriers to regional flow include Precambrian crystalline basement, upper Precambrian and Lower Cambrian clastic sedimentary rocks, and Jurassic to Tertiary granitic rocks. Basin-fill aquifers...
Biomass patterns in seagrass meadows of the Laguna Madre, Texas
Christopher P. Onuf
1996, Bulletin of Marine Science (58) 404-420
The Laguna Madre of Texas supports the most extensive seagrass meadows in the western Gulf of Mexico, In 1988 seagrasses covered 730 km2 or about three-quarters of the embayment. Halodule wrightii dominated the entire upper laguna, and total biomass was quite uniform near 160 g˙m-2 throughout. Four species shared dominance in...
Mississippian stratigraphic framework of east-central California and southern Nevada with revision of Upper Devonian and Mississippian stratigraphic units in Inyo County, California
Calvin H. Stevens, Darrell S. Klingman, Charles A. Sandberg, Paul Stone, Paul Belasky, Forrest G. Poole, J. Kent Snow
1996, Bulletin 1988-J
No abstract available....
Large-scale right-slip displacement on the East San Francisco Bay region fault system, California: Implications for location of late Miocene to Pliocene Pacific plate boundary
R. J. McLaughlin, W.V. Sliter, D. H. Sorg, P.C. Russell, A.M. Sarna-Wojcicki
1996, Tectonics (15) 1-18
A belt of northwardly younging Neogene and Quaternary volcanic rocks and hydrothermal vein systems, together with a distinctive Cretaceous terrane of the Franciscan Complex (the Permanente terrane), exhibits about 160 to 170 km of cumulative dextral offset across faults of the East San Francisco Bay Region (ESFBR) fault system. The...
Organic geochemistry applied to environmental assessments of Prince William Sound, Alaska, after the Exxon Valdez oil spill—a review
A.E. Bence, Keith A. Kvenvolden, M.C. Kennicutt II
1996, Organic Geochemistry (24) 7-42
Organic geochemistry played a major role in the environmental assessments conducted following the Exxon Valdez oil spill, which occurred on March 24, 1989, and released about 258,000 bbls (41 million liters) of Alaska North Slope crude oil into Prince William Sound. Geochemical analyses of more than 15,000 sediment, tar, and biological samples...
40Ar/39Ar whole-rock data constraints on Acadian diagenesis and Alleghanian cleavage in the Martinsburg formation, eastern Pennsylvania
R. P. Wintsch, Michael J. Kunk, Jack B. Epstein
1996, American Journal of Science (296) 766-788
A comparison of 40Ar/39Ar age spectra of whole-rock mudstone and slate samples from the Ordovician Martinsburg Formation at Lehigh Gap, Pennsylvania and stratigraphic and thermal constraints support Alleghanian age for regional slaty cleavage and a late Acadian age for diagenesis in these rocks. Age spectra from mud-stones have a sigmodal shape,...
Using landscape ecology to test hypotheses about large-scale abundance patterns in migratory birds
Curtis H. Flather, John R. Sauer
1996, Ecology (77) 28-35
The hypothesis that Neotropical migrant birds may be undergoing widespread declines due to land use activities on the breeding grounds has been examined primarily by synthesizing results from local studies. Growing concern for the cumulative influence of land use activities on ecological systems has heightened the need for large—scale studies...
Tributary debris fans and the late Holocene alluvial chronology of the Colorado River, eastern Grand Canyon, Arizona
R. Hereford, K. S. Thompson, K. J. Burke, H.C. Fairley
1996, Geological Society of America Bulletin (108) 3-19
Bouldery debris fans and sandy alluvial terraces of the Colorado River developed contemporaneously during the late Holocene at the mouths of nine major tributaries in eastern Grand Canyon. The age of the debris fans and alluvial terraces contributes to understanding river hydraulics and...
The southern Whidbey Island fault: An active structure in the Puget Lowland, Washington
S. Y. Johnson, C. J. Potter, J.M. Armentrout, J. J. Miller, Carol A. Finn, C.S. Weaver
1996, Geological Society of America Bulletin (108) 334-354
Information from seismic-reflection profiles, outcrops, boreholes, and potential field surveys is used to interpret the structure and history of the southern Whidbey Island fault in the Puget Lowland of western Washington. This northwest-trending fault comprises a broad (as wide as 6–11 km), steep, northeast-dipping zone that includes several splays with...
Record of middle Pleistocene climate change from Buck Lake, Cascade Range, southern Oregon - Evidence from sediment magnetism, trace-element geochemistry, and pollen
J. G. Rosenbaum, R. L. Reynolds, D.P. Adam, J. Drexler, A.M. Sarna-Wojcicki, G.C. Whitney
1996, Geological Society of America Bulletin (108) 1328-1341
Comparison of systematic variations in sediment magnetic properties to changes in pollen assemblages in middle Pleistocene lake sediments from Buck Lake indicates that the magnetic properties are sensitive to changes in climate. Buck Lake is located in southern Oregon just east of the...
