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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...

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...

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...

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...

No abstract available....

No abstract available....

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 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...

In July 1971, a study of the effects of mine drainage on Colorado's streams was begun in cooperation with the Colorado Water Pollution Control Commission. The objectives of this study were to determine the extent and magnitude of the problem as a whole, and to gain a greater understanding of...

Colorado is a child of mining. In the past, towns such as Cripple Creek, Leadville, Creede, and many others were the lifeblood of the economy. While metal mining is still economically important to Colorado, another legacy of this past activity is attracting increasing attention—the detrimental effects of drainage from abandoned...

The Climax mine contains three molybdenite ore bodies and widespread late quartz-pyrite-sericite barren mineralization, each related to separate intrusive phases of the Climax stock. Alteration zones spatially related to each molybdenite ore body include a silica zone below, a potassium-silicate zone that approximately coincides with ore, and overlying quartz-sericite-pyrite-topaz, argillic,...

Distribution patterns for biotitic alteration, sericitic alteration, and distinctive fluid-inclusion types in igneous host rocks of the porphyry copper ore body at Bingham, Utah, have been determined by petrographic examination of about 300 samples. These patterns are related to differences in original rock composition, variations in physical-chemical conditions during periods...

Silicoflagellates are important biostratigraphic markers for age determination in nontropical regions because age-diagnostic calcareous microfossils are sparse. Upper Cretaceous and Cenozoic biostratigraphic zonation is proposed, based on silicoflagellates from Deep Sea Drilling Project sites in the subantarctic region....

The Antictam Creek basin in the Great Valley of Maryland and Pennsylvania is underlain almost entirely by intensely folded and faulted lower Paleozoic carbonate rocks. The ground-water discharge of the basin is about 85 percent of the total discharge, in contrast with less than 70 percent of the total discharge...

The computer program, WATEQ, calculates the equilibrium distribution of inorganic aqueous species of major and important minor elements in natural waters using the chemical analysis and in situ measurements of temperature, pH, and redox potential. From this model, the states of reaction of the water with solid and gaseous phases...

The basal beds of the Maquoketa Shale in northeastern Iowa include a basal silty phosphorite layer that is thickest near Dubuque. In Clayton County, Iowa, the bed averages about 1 foot thick (30 centimeters) and contains 22.5 percent P205 . Phosphatic dolomite that is 8 10 feet (2.4 3 meters)...

Garrelsite, NaBa3Si2B7O16(OH)4, originally described in 1955, has recently been reexamined by Charles Milton and Adolf Pabst and by Subrata Ghose and Horst H. Ulbrich. The latter have reanalyzed the mineral and determined the structure; the powder pattern is indexed on the basis of their 1972 cell constants. These were refined...

Biotite and its alteration products (primarily chlorite) from igneous rocks around the Ray and Esperanza (Esperanza-Sierrita) porphyry copper deposits, Arizona, were analyzed for copper by electron microprobe. The copper occurs in amounts >90 p/m (limit of detection) in most of the chlorites analyzed, is concentrated at the optical and chemical...

Studies of drill cores from the Catheart Mountain molybdenum-copper deposit indicate that the deposit is of the porphyry type. Hydrothermal alteration and sulfide mineralization are probably distributed in complex but systematic alteration zones. Most or all mineralization at Catheart Mountain is in a medium-fine-grained quartz monzonite enclosed within a larger...

A simple and rapid method was developed for determining sub milligram amounts of total water in silicate and carbonate minerals. Powdered samples are fused by heating with sodium tungstate vanadium pentoxide flux in a Vycor combustion tube, and the evolved water vapor is absorbed on silica gel. After the water...

A. proposed classification is outlined for 39 species of colonial rugose corals in 10 genera belonging to the families Stauriidae, Craspcdophyllidae (including Cylindrophyllinae new subfamily and Craspedophyllinac), Disphyllidae?, and Zaphrentidae, from the Onesquethaw and lower Cazenovia Stages in New York and adjacent areas. These corals are described or redescribed in...

The depressions in the cone karst (Kegelkarst) of the area west of Ciales in the Lares Limestone are alined in dry valleys that have dendritic patterns. These valleys apparently record the former existence of a cover of noncalcareous clastic material that was deposited on the limestone in late Tertiary time....