Book Description

Excerpt from Preliminary Geologic Investigations of Rock Tunnel Sites for Flood and Pollution Control in the Greater Chicago Area A system of over 100 miles of tunnels in the bedrock has been proposed for the greater Chicago area to intercept overflow from the existing combined sanitary-storm water sewer system and to convey it to temporary storage chambers excavated in the rock. Geologic investigations made during a study for the tunnel sites included test drilling and coring, geophysical logging of bore holes, laboratory testing of samples, seismic surveying, and testing for ground water. The drilling, coring, and logging furnished data that will be of considerable help in mapping and describing the indi vidual units of Silurian and Ordovician strata of the area. The seis mic survey indicated numerous closed depressions on the surface of the bedrock and also suggested that several faults with displacements of 10 to 50 feet are present on the top of the Galena Group. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.