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This report presents the generalized hydrogeologic framework of the Puget Sound aquifer system in Washington and British Columbia. The framework includes a conceptual model of the division of the aquifer system into regional hydrogeologic units for describing on a regional basis the ground-water flow in the system. The conceptual model...

Recent advances in molecular technology have opened a new chapter in species conservation efforts, as well as population biology. DNA sequencing, MHC (major histocompatibility complex), minisatellite, microsatellite, and RAPD (random amplified polymorphic DNA) procedures allow for identification of parentage, more distant relatives, founders to new populations, unidentified individuals, population structure,...

We studied waterfowl use of grass-sage stock ponds in north-central Wyoming during the 1988 and 1989 breeding seasons. Dabbling ducks, particularly mallards, were the most common breeders. Indicated breeding pair density averaged 2.7 pairs/ha of wetland surface, while brood density averaged 1.0 brood/ha of wetland surface. Waterfowl use and productivity...

The common loon (Gavia immer) is a high‐trophic‐level, long‐lived, obligate piscivore at risk from elevated levels of Hg through biomagnification and bioaccumulation. From 1991 to 1996 feather (n = 455) and blood (n = 381) samples from adult loons were collected between June and September in five regions of North America: Alaska,...

Ecological theory and wildlife management often depend on reliable comparison and interpretation of population density estimates. A synthesis of 1,772 mammalian carnivore population estimates (713 unique to reference, species, site, and size of study area) from 74 species revealed global patterns among aspects of study and interpretive design that undermine...

The accuracy and precision of five tools used to measure stream water surface slope (WSS) were evaluated. Water surface slopes estimated in the field with a clinometer or from topographic maps used in conjunction with a map wheel or geographic information system (GIS) were significantly higher than WSS estimated in...

The turquoise group has the general formula: A (sub 0-1) B 6 (PO 4 ) (sub 4-x) (PO 3 OH) x (OH) 8 .4H 2 O, where x = 0-2, and consists of six members: planerite, turquoise, faustite, aheylite, chalcosiderite and an unnamed Fe (super 2+) -Fe (super 3+) analogue. The existence of "coeruleolactite" is doubtful. Planerite is revalidated as a...

Results from a regional-scale ground-water flow model of the Fennoscandian shield suggest that ground-water flow is strongly affected by surface conditions associated with climatic change and glaciation. The model was used to run a series of numerical simulations of variable-density ground-water flow in a 1500-km-long and approximately 10-km-deep cross-section that...

Field exposures of Bufo boreas embryos to fractions of ambient UV-B radiation at two sites in Rocky Mountain National Park, Colorado, USA, were conducted to evaluate UV-B as a possible cause of recent severe declines of this species. There were no differences in hatching success of B. boreas embryos exposed to 0–100% of ambient...

No abstract available...

Surface processes accelerated by severe storms during the 1997–1998 El Niño event scoured hillsides and damaged property across coastal California. Technological advances such as digital mapping, exemplified here for the San Francisco Bay area but applicable elsewhere, have enabled government agencies to better describe, monitor, and predict the effects of...

Egg sampling confirmed that Suwannee River Gulf sturgeon Acipenser oxyrinchus desotoi, a subspecies of Atlantic sturgeon A. o. oxyrinchus use the same spawning site at river kilometer (rkm) 215 from the mouth of the river each year. Forty-nine eggs were recorded in 1995, and 368 were recorded in 1996. Spawning began 4–7...

We present evidence for a hypothesis that the deepwater ciscoes (Coregonus spp.) of the Laurentian Great Lakes were selected for buoyancy-regulation traits that facilitated planktivory on Mysis relict, a crustacean that undertakes extensive diel vertical migration (DVM). We assessed the vertical distribution and behavior of bloaters (C. hoyi) in Lake...

Mineral deposits commonly occur within special geologic units or structures, such as fault zones, which can be detected and mapped from aircraft and satellite images. Modern techniques analyze multispectral images that record the way solar energy is reflected or emitted by the materials exposed at the Earth's surface. In sparsely...

As a result of public controversy over recommendations related to the wilderness preservation system, the U.S. Geological Survey (USGS) conducted a series of reviews of its mineral-resource assessment methods. The first review panel recommended several short- and long-term modifications to improve future mineral-resource assessments (Harris and Rieber, 1993). Implementation of...

Mineral resources are essential to our society. For each person in the United States, approximately 10 tons of minerals are mined annually. Most of this consumption is of bulk mineral commodities (principally aggregates such as sand, gravel, and crushed stone) that are used locally, within about 30 miles of the...

More than 3 million square miles (nearly 8 million square kilometers) of territory that belongs to the United States is relatively unknown. This area is the Exclusive Economic Zone (EEZ), which extends from 3 nautical miles (5.6 km) off the coast of the United States and its affiliated islands out...

The Pacific Section, S.E.P.M. 1998 Fall Field Trip will traverse rocks of the Gualala block of northern California. Seven stops (Figure 1) will be made in one and a half days and will examine a variety of geologic features and rock types in this significant area. The field trip is...

Increasing residential and commercial development is placing increased demands on the ground- and surface-water resources of Snyderville Basin, Park City, and adjacent areas in the southwestern corner of Summit County, Utah. Data collected during 1993-95 were used to assess the quantity and quality of the water resources in the study...

No abstract available...

The natural establishment of woody seedlings on abandoned agricultural fields was investigated at sites in Louisiana and Mississippi. Series of disked and undisked plots originating at forest edges and oriented in cardinal directions were established on fields at each site. During the firest 2 years, seedling recruitment was dominated by...

This report provides the results of a detailed Level II analysis of scour potential at structure STOCTH00360005 on Town Highway 36 crossing Stony Brook, Stockbridge, Vermont (figures 1–8). A Level II study is a basic engineering analysis of the site, including a quantitative analysis of stream stability and scour (U.S....

On June 24, 1942, the temporary Military Geology Unit of the U.S. Geological Survey was formalized after the U.S. Army Corps of Engineers requested them to prepare terrain intelligence studies to meet wartime priorities. The entire Military Geology Unit wartime roster was 114 professionals, including 88 geologists, 11 soil scientists,...