Call number:
ZSP-201-81/13
In:
CRREL Report, 81-13
Description / Table of Contents:
Electrical properties of frozen ground were measured using radio frequency interferometry (RFI) in the very high frequency (VHF) radiowave band. Ice-rich organic silts and sands and gravels of variable ice content were investigated during early April of both 1979 and 1980. Frequencies between 10 and 150 MHz were used with best results obtained between 40 and 100 MHz. Surface impedance and magnetic induction techniques were also used to obtain an independent measure of low frequency resistivity and to obtain a separate control on vertical inhomogeneity. Soil samples were tested for organic and water content. The dielectric constants determined for the ice-rich organic silts ranged from 4.0 to 5.5 while those for the sands and gravels were about 5.1. Dielectric loss was due to d.c. conduction and was very low for the silts but significant for the sands and gravels. The higher values for the sands and gravels were most likely due to the higher concentrations of salt that are reported to exist in the old beach ridges in this region. All the RFI measurements are believed to be indicative of only the first few meters of the ground although the radiowaves could penetrate to tens of meters.
Type of Medium:
Series available for loan
Pages:
iv, 18 Seiten
,
Illustrationen
Series Statement:
CRREL Report 81-13
URL:
https://hdl.handle.net/11681/9466
Language:
English
Note:
CONTENTS
Abstract
Preface
Introduction
Background
Objectives and procedures
Theory and instrumentation
Radio frequency interferometry
Case 1: Homogeneous ground model
Case 2: Two-layer ground model
RFI instrumentation
Low frequency methods
Point Barrow sites
Results and discussion
Site 1: Tundra
Site 2: Beach ridge
Site 3: Marsh
Conclusions
Literature cited
Appendix A: Discussion of low-frequency geophysical methods
Location:
AWI Archive
Branch Library:
AWI Library
