Seismic Investigation of Ice Properties and Bedrock Topography at the Confluence of Two Glaciers, Kaskawulsh Glacier, Yukon Territory, Canada

The field investigations were carried out as part of the Icefield Ranges Research Project.The purpose of this study is twofold: (1) to investigate seismic velocity inhomogeneity and anisotropy in strongly deformed glacier ice; and (2) to determine the form and dimension of that part of a sub-glacial valley where two large temperate glaciers merge. The field investigations were carried out during the summers of 1964 and 1965 at the confluence of the North and Central Arms of the Kaskawulsh Glacier in the St. Elias Mountains, Yukon Territory, Canada. Results of the fieldwork are discussed in detail.Arctic Institute of North AmericaExplorer's Club of New YorkU.S. National Science Foundation, Office of Antarctic Program

Seismic Surface Wave Observations in West Antarctica

Explosion-produced seismic surface waves recorded along the Byrd Station Strain Network in West Antarctica were investigated. Amplitudes were much greater for Rayleigh waves than for Love waves. Higher modes of both wave types were registered. Group velocity dispersion analysis revealed significant lateral inhomogeneity in near-surface structure of the ice sheet throughout the study area. Velocity anisotropy was indicated at one site.U.S. National Science Foundation Grants GA-1141 and GA-14425

Substance use and misuse in the aftermath of terrorism: A Bayesian meta-analysis

Aim To conduct a comprehensive analysis of the conflicting evidence on substance use and misuse following mass traumas such as terrorist incidents. Methods We reviewed and synthesized evidence from 31 population-based studies using Bayesian meta-analysis and meta-regression. Results The majority of the studied were conducted in the aftermath of the terrorist attacks of 11 September 2001. Controlling for exposure, type of incident and time since the event occurred, 7.3% [95% credible interval (CrI) 1.1-32.5%] of a population can be expected to report increased alcohol consumption in the first 2 years following a terrorist event. There is, however, a 20% probability that the prevalence will be as high as 14%. The unadjusted prevalence of increased cigarette smoking following a terrorist event is 6.8% (95% Cr I 2.6-16.5%). Unadjusted reports of mixed drug use (including narcotics and prescription medications) was 16.3% (95% Cr I 1.3-72.5%). Conclusions These results underscore the potentially pervasive behavioral health effects of mass terrorism, and suggest that public health interventions may usefully consider substance use as an area of focus after such events

A Magnetic Profile in the Gerlache Strait, Antarctica

"RF Project 2264, Report No. 1"A profile of the total magnetic field was obtained along a 208 km track in Gerlache Strait, a tectonic depression off the west coast of the Antarctic Peninsula. There is no direct correlation between bottom topography and magnetic intensity. A very low magnetic gradient exists where the profile parallels the regional tectonic trend. Sharp anomalies occur where the profile crosses the tectonic trend.National Science Foundation Grant GA-529

The relation of microseisms to meteorological conditions

Thesis. (M.S.) Massachusetts Institute of Technology. Dept. of Geology, 1954.Bibliography: leaves 113-114.by Gilbert Dewart.M.S

Analysis of the Byrd Station Strain Net, Antarctica

On cover: RF 2500.This report presents some results of field investigations relating to the study of glacier flow in Marie Byrd Land, Antarctica. The physical quantities necessary for a solution to the problem of the mode of flow of the continental ice sheet in the Ross glacial drainage basin are being sought by several principal lines of investigation: determination of surface strain rate and surface slope by analysis of precise surveys of the Byrd Station Strain Net that have been carried out by the Topographic Branch of the U.S. Geological Survey; determination of strain rate and temperature distribution at depth in the deep hole at Byrd Station drilled by the U.S. Army Cold Regions Research and Engineering Laboratory; determination of ice thickness and of glacier bed configuration and conditions by geophysical exploration, including seismic, gravimetric, magnetic and radio-echo sounding methods; analysis of the structure and dynamic physical properties of ice; and observation of snow deposition and metamorphosis and surface morphology in order to explain parts of the core from Byrd Station deep drill hole, and estimate the mass balance. Much of the material presented in the report is based upon observations made by field parties which were based at Byrd Station and operated in the region of the Byrd Station Strain Net, which lies between Byrd Station and the Ross-Amundsen ice divide, during the austral summers of 1967-68, 1969-70, 1971-72, and 1973-74.National Science Foundation Grants GA-1141, GA-14425 and GV-26137X