Publications

No abstract available.

No abstract available. 

This paper describes how the equivalent of a least‐squares adjustment of a level or traverse net may be obtained by electrical measurements in an analogous electrical net. The lengths of the survey lines are replaced by proportional electrical resistances; the survey closures are replaced by proportional small dc voltages; the adjustment corrections are read as electrical potentials at the various

No abstract available.

A record of the activity of Parícutin Volcano, Michoacán, Mexico, is shown in the diagram of eruptive characteristics, Figure 1, covering the period December 31, 1946 to March 31, 1947, and is supplemented by the maps of the areal extent of the lava flows, Figures 2 and 3. This continues the previous record for the period from September 18 to November 30, 1946 [Trans. Amer. Geophys. Union, v. 28,

No abstract available. 

The two formations and eight members that constitute the Upper Cambrian in the Llano uplift of central Texas are described or redefined, and their lithic characters in 19 measured sections are graphically summarized. Standard reference to them is thus furnished.The Riley formation comprises the basal Paleozoic strata of the Llano uplift. Its initial sediments were deposited on a submerged pre-Camb

By definition European geologists consider a sequence of limestones, sandstones, and shales, the beds of which are thin, regular, and alternating, and which are deposited in a geosyncline or foredeep shortly before a major orogeny, as the flysch. The waste products that accumulate as a deposit flanking mountains and built in part of the deformed flysch make up the molasse. In field practice the gr

Complete chemical analyses, including the spectrographic determination of 44 trace elements, have been made of six representative specimens from each of the six map units constituting the Oliverian magma series in the Mt. Washington quadrangle of New Hampshire. Potash is systematically higher than soda. An increase in silica, which ranges from 56 to 75 per cent, is accompanied by the usual variati

This report is on result of a long program of geologic investigation in south-central Idaho, undertaken as an aid in the development of the mineral resources of the region. This quadrangle was examined because of the exceptional opportunities for the study of stratigraphy and structure afforded by the Lost River Range, which is the highest in Idaho and contains comparatively few intrusive igneous

Determination of the ground‐water supply available from any aquifer or in any specified area requires not merely the application of specific quantitative methods but also a broad and accurate knowledge of the geologic, hydrologlc, and geochemical factors that are involved, and consideration of the economic and legal limitations. Further research is needed as to geologic texture and structure in re

Scheelite accompanies ferberite as an ore of tungsten at many localities in the Boulder tungsten district. It is only of accessory importance in most veins, but in a few mines it affects grade of the ore substantially. It occurs in small veins, in vugs, disseminated in sericitized rock, and in gouge and minute fractures in shear zones. The vein and shear-zone deposits are the most important econom