This report describes, in 7 sections, physiographic and hydraulic studies of rivers.

From introduction: The present study was undertaken to extend and supplement a mapping program covering several ranges north and northwest of Lake Mead.

From Purpose and Scope of Report: This report presents a detailed description of the ore deposits of the Picher field and all phases of geology having a bearing on their localization, origin, and the search for them. It is based mainly on work done by the U.S. Geological Survey, but it also incorporates pertinent data from published literature, especially from the outstanding work of George M. Fowler and associates, and some unpublished data obtained from the geologic staffs of the mining companies.

From abstract: The Geysers-Clear Lake geothermal area lies within the central belt of the Franciscan assemblage in northern California. The structure of this terrane is characterized by northeast-dipping imbricate thrust slices that have been warped and cut by steeply dipping strike-slip and normal faults. Introduction of magma into the crust beneath the Geysers-Clear Lake area can be related to eastsoutheast extension accompanying northward propagation of the San Andreas transform system between the Clear Lake region and Cape Mendocino within the last 3 million years. The initiation of strike-slip faulting during this time terminated subduction of elements of the Farallon plate beneath North America as strike-slip motion was taken up along the Pacific-North American plate boundary. The mechanism for magma generation appears to require a heat source in the mantle that mixed mantle-derived melts with various crustal rocks. These crustal rocks may have included the Franciscan central and coastal belts, ophiolite, Great Valley sequence, and possibly middle and late Tertiary rocks subducted before initiation of strike-slip faulting.

From abstract: Platinum placers were discovered in 1926 in a small area south of Goodnews Bay, in southwestern Alaska. Beginning in 1927, the placers were worked for 7 years by small-scale mining methods; in later years dragline excavators and a dredge were utilized. These deposits are important, not only because they are of high grade but because they are the only commercial source of platinum metals in the United States. This report details the deposits in this district.

A report regarding the general geology and mines of the East Titanic Mining District, in Tuah and Juab Counties, Utah.

Abstract: The Oquirrh Group of Pennsylvanian and Permian age in the southern East Tintic Mountains, Utah, is more than 15,000 feet (4,572 m) thick and consists of an incomplete section of the West Canyon Limestone (Morrowan) 960 feet (293 m) thick, a nearly complete section of the Butterfield Peaks Formation (Atokan(?) and Des Moinesian) about 5,800 feet (1,768 m) thick, a complete section of the Bingham Mine Formation (Missourian) 3,200-3,400 feet thick (975-1,036 m), and a complete section of the newly named Furner Valley Limestone (Missourian to Wolfcampian) 5,000-6,000 feet (1,524-1,829 m) thick. The formations below the Furner Valley Limestone are generally similar to their counterparts in their type areas in the central and southern Oquirrh Mountains but are somewhat thinner and less arenaceous. The Furner Valley Limestone, more than 90 percent carbonate, is apparently unique. Strata of the same age in the Wasatch, Stansbury, Cedar, Hogup, and Promontory Mountains in Utah are all considerably arenaceous; in the southern Oquirrh Mountains in the upper plate of the Midas thrust fault they have been largely removed by erosion. The Oquirrh Group in the East Tintic Mountains is overlain by the Diamond Creek Sandstone; the latter, in turn, is overlain by the …

Introduction: This work is an alphabetical list of the geographic names that are now applied and have been applied to to places and features of the Alaska Landscape.

From abstract: The seismic history of the southeastern United States is dominated by the 1886 earthquake near Charleston, S.C. An understanding of the specific source and the uniqueness of the neotectonic setting of this large earthquake is essential in order to properly assess seismic hazards in the southeastern United States. Such knowledge will also contribute to the fundamental understanding of intraplate earthquakes and will aid indirectly in deciphering the evolution of Atlantic-type continental margins. The 15 chapters in this volume report on the first stage of an ongoing multidisciplinary study of the Charleston earthquake of 1886.

Study of the geology and ore deposits of the Breckenridge District in Colorado.

From introduction: This report deals with the stratigraphic and ecologic significance of Foraminifera contained in a Tertiary sequence that crops out in the northern part of the Olympic Peninsula, Wash. (pl. 1). The work was done as a part of a program of geologic investigations for oil and gas possibilities conducted by the U.S. Geological Survey.

Abstract: Aerial photographs today are widely used to obtain both qualitative and quantitative geologic information; vertical aerial photographs are used almost to the exclusion of other types. Techniques and procedures described herein relate primarily to vertical photography.

From introduction: The objectives of this report are to (1) document the stratigraphic framework of the Santa Margarita Formation and part of the Monterey Shale in the southern Temblor Range, (2) interpret the environments of deposition and depositional processes of the above units, and (3) evaluate the influence of tectonism on Santa Margarita sedimentation, with special attention given to testing the hypothesis of Berry and others (1968).

From abstract and introduction: Mineralogic and stratigraphic studies of the lower part of the Pierre Shale of Late Cretaceous age along the Missouri River indicate correlations different from those generally accepted. The purposes of this paper are to present evidence for the new correlations and to resolve problems of formal nomenclature that result from them.

A report regarding thorium resources located in the Mountain Pass District in San Bernadino County, California

Abstract: Steamboat Springs is a presently active equivalent of epithermal gold-silver ore-forming systems. Hot-spring sinter deposits contain small amounts of gold, silver, mercury, antimony, and arsenic. Hot-spring activity probably started before extrusion of the basaltic andesite of Steamboat Springs. Old sinter from the Steamboat Springs system occurs in gravels above and below the basaltic andesite. Intense hydrothermal alteration, including almost complete replacement by hydrothermal potassium-feldspar, has affected the basaltic andesite. Three plagioclase separates of differing potassium content from fresh basaltic andesite yielded potassium-argon ages of 2.52 to 2.55 m.y. Basaltic andesite almost completely replaced by potassium-feldspar yielded an age of 1.1 m.y. The source of energy for the thermal convection system is probably a large rhyolitic magma chamber that supplied the pumice and from which the rhyolite domes were emplaced. Sanidine and obsidian from four of the rhyolite domes yielded potassium-argon ages of 1.15 to 1.52 m.y. and obsidian from one of the northeastern domes yielded apparent ages of 2.97 and 3.03 m.y. The data indicate that hydrothermal activity has occurred at Steamboat Springs, possibly intermittently, for more than 2-1/2 m.y. These data agree with other radiogenic age studies indicating 1- and 2-m.y. lifetimes for the hydrothermal systems that generate …

Abstract: Quantitative statistical sampling of plant debris entombed within deltaic sediments of a Holocene fluviolacustrine environment at Silwood Lake, Berkshire, demonstrates that patterns of deposition exist that can be used to reconstruct the relative spatial distributions of species within the source vegetation.

Abstract: Examination of previously described and some undescribed leaves of Ulmus and Zelkova from the later Oligocene, Miocene, and Pliocene of western North America indicates that at least eight species of Ulmus and two species of Zelkova are represented. Three new species are described: Ulmus chaneyi, U. knowltoni, and Zelkova browni.

Physiography and glacial geology of the Yakutat Bay Region in Alaska.

From introduction: The study of the Crystal Mountain district, Larimer County, Colo., is but one phase of this post-World War II pegmatite program, in part carried out by the Geological Survey on behalf of the Division of Raw Materials of the Atomic Energy Commission.

From introduction: The U.S. Geological Survey has selected and assembled 67 sets of aerial photographs that illustrate a variety of geologic features in Antarctica, South and Central America, the southwest Pacific, Iran, Japan, the Arabian Peninsula, Pakistan, and mainland China. Contact prints of the photographs composing these sets are available for purchase. Sets of photographs of geologic features in the United States and Puerto Rico are listed in a separate catalog (Denny, C. S., and others, 1968, A descriptive catalog of selected aerial photographs of geologic features in the United States: U.S. Geol. Survey Prof. Paper 590).

From Introduction: The field work that furnished the basis for this report was begun in 1930 and was continued at intervals until 1934. The anticlinal character of the Kettleman Hills is apparent to even the casual observer, but the many structural complications due to an intricate network of minor faults, at least in North Dome and Middle Dome, are much less obvious. Though it is improbable that these faults have any relation to the occurrence of oil, an attempt was made to map them, not only to represent the structure adequately but also because the stratigraphy could not be understood if they were neglected. Faunal zones were particularly useful in mapping. On the other hand, some lithologic units proved to be more persistent than had been expected. The two sets of features-fossils and lithology-served as checks on each other.