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Geologic mapping at scale 1:24,000 of the Edna Mountain 15-minute quadrangle, Humboldt County, Nev., revealed two episodes of pre-Mesozoic deformation that are difficult to reconcile with either the Antler or the Sonoma orogeny. We believe that the older episode predated the Antler orogeny and may be as old as Late...

The Border Ranges fault, a major fault of southern Alaska, can be traced for more than 1,000 km arcuately eastward from Kodiak Island to the St. Elias Mountains. Throughout its extent, the fault juxtaposes upper Paleozoic and lower Mesozoic rocks on the north against upper Mesozoic and Tertiary rocks. This...

A. northwest-trending belt of steeply east-dipping Precambrian and Paleozoic sedimentary rocks extends across the Winkelman 15-minute quadrangle and separates areas of contrasting structures. To the southwest for 60 mi is an expanse of Precambrian basement, largely granite; to the northeast the Precambrian and Paleozoic sedimentary rocks are gently tilted and...

A stratigraphic zonation based on silicoflagellates is proposed for the division of Upper Cretaceous to lower Miocene deep-sea sediments into eight independent zones. The occurrence of silicoflagellate siliceous microfossils from Mesozoic and lower Cenozoic sediment has been poorly known in all but the middle Eocene. The most diagnostic occurrences in...

The largest potential reservoir for the storage of potable water is in the unsaturated zone. Use of this space for the storage and retrieval of potable water is a multifaceted problem which requires application of the best talent from the scientific community.Artificial recharge has many similarities to liquidwaste disposal through...

Palaeomagnetic results have been obtained from thirty sites in intrusive and extrusive rocks of Oligocene age from the San Juan Mountains, south-western Colorado. All specimens from each site were subjected to af demagnetization, and the reliability of each site determined. Twenty-three sites gave reliable results. Because five sites from the...

Seismic reflection data indicate that the Atlantic plate has been underthrust beneath the Caribbean plate east of the Lesser Antilles. The data further reveal that the transition from underthrust to strike-slip plate motion occurs near lat 19.3° N. and long 62° W. in alinement with the Anegada Trough. Oceanic basement...

The temperature and chemical conditions (pH, gas pressure, and ion activities) in a geothermal aquifer supplying a producing bore can be calculated from the enthalpy of the total fluid (liquid + vapor) produced and chemical analyses of water and steam separated and collected at known pressures. Alternatively, if a single...

The water in many warm springs with large rates of flow consists of mixtures of hot water that has come from depth and of shallow cold water. Under favorable conditions the original temperature of the hot water and the fraction of the cold water in the mixture can be estimated...

The chemical and isotopic compositions of hot-spring water and gas are used to estimate subsurface temperatures. The basic assumptions inherent in the methods are seldom stipulated. These assumptions include (1) a temperature-dependent reaction at depth, (2) a supply of the solid phase involved in the reaction to permit saturation of...

A revaluation of the 25° C activity-product constants of calcite (KC) and aragonite (KA) was made on the basis of the known solubilities of these phases for which the activity of total dissolved calcium was corrected for the presence of the ion pair CaHCO3+ in the aqueous phase. The value...

The restrictive assumptions required by most available methods for estimating survival probabilities render them unsuitable for analyzing real banding data. A model is proposed which allows survival rates and recovery rates to vary with the calendar year, and also allows juveniles to have rates different from adults. In addition to...

Multispectral photography and ground truth were obtained on an area 12 miles (19.3 km) east of Bemidji, Minnesota, to identify and map wetlands less than 2 acres (0.8 hectare) in size, to map emergent vegetation in lakes, and to explore the feasibility of classifying vegetation from aerial photographs. Wetlands less...

A total of 211 wild, free-flying mallards (Anas platyrhynchos) and wood ducks (Aix sponsa) were equipped with breast-mounted radio packages during the breeding seasons of 1968-72. Known predation loss was 7.6 and 12.0 percent for mallards and wood ducks respectively, 60 percent occurred within 3 weeks of instrumentation. The highest...

Statistical multiple-regression analyses showed significant relationships between trout populations and hydrologic parameters. Parameters showing the higher levels of significance were temperature, hardness of water, percentage of gravel bottom, percentage of bottom vegetation, variability of streamflow, and discharge per unit drainage area. Trout populations increase with lower levels of annual maximum...

Duck nesting was studied during 1971 in north-central South Dakota under four conditions: in idle, five or six year old fields of domestic grass-legume mixtures in an area where predators including the red fox (Vulpes fulva), raccoon (Procyon lotor), striped skunk (Mephitis mephitis), and badger (Taxidea taxus) were (1) reduced...

A 2-year supplemental feeding program for the endangered California condor (Gymnogyps californianus) was of insufficient length to definitely show that a dependable food supply will stimulate additional breeding; however, production did increase during the study, and food supply appears a likely cause. Because no undesirable effects of feeding were noted,...

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A detailed magnetic survey in the southern Gulf of Mexico shows subdued irregular magnetic anomalies that are similar in wave length to those attributed to sea-floor spreading on present-day oceanic rises. The small amplitude of these anomalies, about 75γ, would be compatible with an oceanic basalt source at a depth...

Basement rocks of parts of eastern Panamá include tholeiitic pillow basalt and diabase overlain by sedimentary rocks typical of deep oceanic environments. Both paleontologic and stratigraphic evidence indicate that some of these rocks are of Late Cretaceous age or older. Regional Bouguer anomalies over the basement terrane exceed +120 mgal,...

Salmonellosis caused by Salmonella typhimurium was one of several factors responsible for losses among young herons being held at the Patuxent Wildlife Research Center. The infection was demonstrated in five black-crowned night herons (Nycticorax nycticorax), three common egrets (Casmerodius albus), two little blue herons (Florida caerulea), one cattle egret (Bubulcus ibis), one...

The Mariner 10 television cameras imaged the planet Venus in the visible and near ultraviolet for a period of 8 days at resolutions ranging from 100 meters to 130 kilometers. The general pattern of the atmospheric circulation in the upper tropospheric/lower stratospheric region is displayed in the pictures. Atmospheric flow...

The Earth Resources Technology Satellite makes it feasible for the first time to monitor the level of activity at widely separated volcanoes and to relay these data almost instantancously to one central office. This capability opens a new era in volcanology where the hundreds of normally...

Orange and red materials were observed and photographed in the dark mantle of the Sulpicius Gallus Formation on the southwestern rim of the Serenitatis basin. These materials occur only within the dark mantle that overlies old rilled mare and highland units and are absent on the younger mare unit in...