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Potassium-argon ages have been determined on 25 biotite and hornblende samples (four coexisting biotite-hornblende pairs were dated) from a number of granitic formations in the more than 500 sq mi of dominantly granitic outcrop in the White Mountains. These new data, together with earlier published radiometric ages, indicate a group...

Existing models for dolomitization emphasize that penecontemporaneous dolomitization can occur in both subtidal and supratidal environments if the necessary chemical and physical factors favorable for the development of magnesium-rich hypersaline waters exist. Holocene shallow-water hypersaline environments that have the potential to produce dolomite without deposition of more soluble evaporite minerals are found in Shark Bay, Australia,...

Graptolites collected from the uppermost part of the Martinsburg Formation (Pen Argyl Member) at and near the contact with the overlying Shawangunk Formation at Lehigh Gap, Pa., indicate that the uppermost Martinsburg is as young as Edenian to early Maysvillian (upper subzone [Climacograptus spiniferus subzone] of zone 13 | Orthograptus truncatus intermedius zone]). The Martinsburg gradationally...

The southern complex, south of the Marquette synclinorium in the Marquette district of Michigan, is dominantly granitic.  The granitic parts of the complex have Rb-Sr ages of about 2.5 b.y. and are classed as of Precambrian W age. The rocks are divided into two major units: (1.) Bell Creek Gneiss consisting mostly of...

Orpiment, As2S3, containing up to 1.5 percent antimony has been recognized in carbonaceous arsenic-rich gold ores in the unoxidized East ore body of the Carlin gold deposit. Associated hydrothermal minerals include realgar (AsS) and quartz. Stibnite, commonly associated with realgar in the ores, has not been observed associated with this type of orpiment....

Lithostrotion reiseri n. sp. is a cerioid, colonial coral, index fossil for microfossil zones 12-13 (Meramec) in the Lisburne Group in the central and eastern Brooks Range, arctic Alaska....

Upper Cretaceous mafic conglomerate and quartz-plagioclase arkose that crop out on the southwest side of the San Andreas fault near Gualala, Calif., may have been eroded from a gabbroic terrane that now lies about 350 miles to the southeast, on the opposite side of the San Andreas fault. The plagioclase arkose near Gualala contains little...

Lava flows and red sandstone beds near the middle of the Upper Precambrian Grand Canyon Series exhibit stable remanent magnetization. The beds are about 1000 m stratigraphically above rocks of the Grand Canyon Series for which paleomagnetic poles have been reported. All...

GROUNDWATER FEATURES OF SIX LOWLAND AREAS IN THE KLAMATH BASIN OF OREGON--KLAMATH MARSH AREA, AND SPRAGUE RIVER, SWAN LAKE, YONNA, POE, AND LANGELL VALLEYS--ARE DESCRIBED. RUGGED MOUNTAINS AND RIDGES SURROUND AND SEPARATE THESE LOWLANDS WHERE FLOORS RANGE IN ALTITUDE FROM 4,100 FEET IN POE...

The shift of the Yukon River, during the Holocene sea-level transgression, from south of Nunivak Island during the Wisconsin maximum to its present location (a distance greater than 300 kilometers) is indicated by remanent channels, distinct subbottom structures, deltaic sediments, and anomalous rates of sediment accumulation on the continental shelf...

During the years 1954-70, 230 pintails (Anas acuta) banded in North America were reported from eastern Asia, primarily Siberia. Most of the birds were shot on the breeding grounds in May. The movement into eastern Asia of pintails banded in the interior of North America was directly correlated with the...

Glacial deposits in the Mesabi-Vermilion Iron Range area consist of four major till units and associated glaciofluvial sediments. Particle-size data and pebble, heavy-mineral, clay-mineral, and percentage-soluble content were used in addition to field description of color and texture to describe and correlate the drift units. The lowermost till unit, basal till,...

This report is one of a series that is prepared by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Rights, which describes water resources in selected areas in Utah. The period of study on which this report was based was from July...

Observed gravity values, station locations, terrain corrections, and Bouguer gravity data are provided in tabular form for approximately 1,500 gravity observations in eastern California. Coverage includes Saline Valley, Panamint Valley, Searles Basin, Death Valley, the southern Amargosa Desert and the enclosed and adjoining highlands. These data were used in preparation...

Since February 1969 Alae Crater, a 165-m-deep pit crater on the east rift of Kilauea Volcano, has been completely filled with about 18 million m3 of lava. The filling was episodic and complex. It involved 13 major periods of addition of lava to the crater, including spectacular...

Conclusions and Recommendations: Although much of the above information is imprecise and inconclusive, it is evident that the condors foraging habitat is diminishing. Food supply probably is still adequate for free-ranging nonbreeding birds, but could become limited if current land use trends continue. Congregating condors on fewer...

Drift, evidently of Illinoian age, was deposited on St. Lawrence Island at the margin of an ice cap that covered the highlands of the Chukotka Peninsula of Siberia and spread far eastward on the continental shelf of northern Bering Sea. Underlying the drift on the northwestward part of the island...

Interpretation of reflection profiles across the Washington continental margin suggests deformation of Cascadia basin strata against the continental slope. Individual reflecting horizons can be traced across the slope-basin boundary. The sense of offset along faults on the continental slope is predominantly, but not...

No abstract available....

The Shawangunk Formation of Early and Middle Silurian age, and possibly Late Ordovician age, in eastern Pennsylvania and northwestern New Jersey forms a thick clastic wedge of sediments derived from sourcelands to the southeast uplifted during the Taconic orogeny. The formation is divided into four newly denned members, from bottom...

The Crow Wing River, a tributary of the Mississippi River, drains an area of about 3,760 square miles, essentially all of which is covered by glacial deposits. Topography of most of the watershed is slightly- to moderately-undulating and has local relief of up to about 50 feet. The margin of the...

Water is available in Clay, Greene, Craighead, and Poinsett Counties from ground-water and surface-water sources. However, ground water is more accessible in many places than surface water. Ground water is available from the alluvium, which covers all the area except Crowleys Ridge, and is also available from other formations below...

This report describes the most outstanding floods in the United States during 1967. The two most destructive floods occurred in August in east-central Alaska and in September and October in southern Texas. In east-central Alaska, heavy rain on August 8-17 produced record-breaking floods near Fairbanks. Peak discharges on some streams...

No abstract available. ...

A prairie pothole is a depression in the prau1e, capable of storing water, that is the result of glacial processes. Years ago, there were many hundreds of thousands of prairie potholes in the North-Central United States, but large numbers of them have been drained for agricultural use. This report is...