From abstract and summary: Project Stagecoach consisted of the detonation of three 40,000-pound charges. Blocks of cast TNT were stacked to resemble a sphere and, the whole center-detonated.

Introduction: "This report presents physical property analyses for 28 additional samples and is a supplement to Geological Survey Technical Letter: Area-12-1, which gave a brief summary of the geology, descriptive data on the tunnel, and X-ray, chemical, semiquantitative spectrographic analyses, and some physical properties determinations of samples collected in the U12g.01 tunnel."

This report summarizes the gravity data of the Area 12, Nevada Test Site.

This report documents the use of the dislocation theory to analyze measured vertical displacements across a fault near the Duryea underground nuclear explosion.

This report presents the physical properties of tuff in the vicinity of the U12g.01 tunnel at the Nevada Test Site based off of two previous Technical Letters on the tunnel: Technical Letter: Area 12-1, and Technical Letter 12-1, Supplement 1.

From abstract: Pegmatite occurs widely in Nevada and northwestern Arizona, but little mining has been done for such pegmatite minerals as mica, feldspar, beryl, and lepidolite. Reconnaissance for beryl-bearing pegmatite in Nevada and in part of Mohave County, Ariz., and detailed studies in the Dawley Canyon area, Elko County, Nev., have shown that beryl occurs in at least 11 districts in the region. Muscovite has been prospected or mined in the Ruby and Virgin Mountains, Nev., and in Mohave County, Ariz. Feldspar has been mined in the southern part of the region near Kingman, Ariz., and in Clark County, Nev.

Abstract: "Fifteen in situ interval densities were calculated from the borehole gravity meter observations made in Test Well-B. The weighted average density for all the rocks sampled by the gravity meter is 1.83 gm/cc. The alluvium density ranges from 1.71 to 1.82 gm/cc and averages 1.76 gm/cc. The lake beds range from 1.91 to 1.93 gm/cc and average 1.92 gm/cc. The Rainier Mesa Member averages 1.83 gm/cc. The Tiva Canyon Member averages 1.74 gm/cc and the upper 110 feet of Topopah Spring Member has a density of 2.30 gm/cc."

Abstract: "Drill hole UCe-18 was successfully logged with the U.S. Geological Survey-La Coste Romberg borehole gravity meter to a depth of 6,488 feet. That density increases with depth is apparent in both the alluvium and volcanic rock. The in situ density of the alluvium measured by the gravity meter ranges from 1.77 to 2.34 gm/cc; the lake beds beneath the alluvium have a density of 2.22 gm/cc; and the rhyolitic rocks range in density from 2.26 to 2.47 gm/cc. The average density determined from the borehole gravity meter data for the alluvium plus the lake beds is 2.22 gm/cc and for the volcanic rocks is 2.35 gm/cc."

This report presents the gravity data of drill hole Ue19n at the Nevada Test Site.

Introduction: The chemical character of ground water depends to a large degree upon the character of the rock formations through which the water moves. The composition of the water is the result of several solutional and decompositional processes.

From abstract: Close-in air blast measurements were made on the Dugout shot. Major constituents of the blast wave were the ground-shock-induced pulse and the pulse from venting gases. The ground-shock-induced pulse was the dominant one at all stations.

From abstract: Many residents of the Nevada area carried film badge radiation dosimeters during Operation Plumbbob in 1957. Badge readings in specific localities appear to follow the logarithmic-normal distribution.

The following report describes the computer technique for tracing seismic rays in two-dimensional geological models in the state during the time this report was written, and presents some preliminary results.

The following report explains the seismic ray models presented in this report.

Abstract: "Available data on wind persistence and wind forecasting capability have been applied in estimating the probability of a fallout pattern shifting from an uninhabited safe sector into a populated region. Safety probability is computed from win variability, forecasting accuracy, initial height and particle size of radioactivity landing at a point in the predicted fallout pattern, predicted wind speed, length of forecast period, and safe-sector angular width."

Report discussing the methods, data, and analysis of results for "An experimental study designed to provide a basis for estimating protection against fallout radiation " (p. v) using one- and two-story structures with basements.

Report concerning the protection offered against radioactive fallout offered by two types of structures at the Nevada Test Site. Differences between above ground and underground structures are measured and compared to data taken from actual fallout conditions.

Report containing information regarding the airborne radiometric equipment intercalibration exercises undertaken by four government agencies and one private companies.

Report on an evaluation of the Sand Springs Range as a possible location for an underground nuclear study (Shoal Event). Various tests to determine the site's suitability included aerial photography and mapping of the area through various means; drilling and bulldozing to conduct mineralogical and other physical evaluations; gravity, aeromagnetic, and refraction surveys; and studies related to the hydrology of the location and surrounding areas.

From introduction: The general objectives of this Geological Survey were to study the geologic and geophysical studies of the effects of underground nuclear explosions under Rainier Mesa.

Abstract: As a part of continuous geologic and geophysical investigations at the Nevada Test Site, gamma-radioactivity measurements are being made in tunnels and drill holes to determine semiquantitatively the natural gamma radioactivity of geologic formations and the distribution of nuclear-explosion-produced radioisotopes.

From introduction: Under the general supervision of the Health Division of the Los Alamos Scientific Laboratory, the U.S. Geological Survey is participating in geologic and hydrologic studies of the tile field constructed in Jackass Flats in the southwestern part of the Nevada Test Site as related to waste disposal, M. D. Shutler rendered valuable assistance in obtaining and evaluating portions of the data in this report. These investigations were done on behalf of the U.S. Atomic Energy Commission and were supported by the Division of Reactor Development and by the Albuquerque Operations Office.

Abstract: "Geodimeter surveys were made on four traverses near the east scarp of Rainier Mesa between October 27, 1967 and April 26, 1968. These measurements were made in order to determine if an changes in distance between survey stations had resulted from downslope creep of the rocks behind the scarp, or if any displacements had resulted from nuclear explosions beneath the mesa and in adjacent areas. A persistent small but possibly significant, slopeward displacement was measured along one traverse and may represent detachment of a large block; monitoring for an additional period of time is recommended."

The following report provides a geological map of sections of the Thirsty Canyon South East quadrangle of Nye County, Nevada.