Anomalous increases in piezometric levels in advance of longwall mining subsidence

Environmental & Engineering Geoscience
By: , and 

Links

Abstract

The typical initial piezometric response to longwall undermining is a decline in head due to the opening of fractures and bedding planes during early subsidence. However, in studies over two active longwall mines in southern Illinois, temporary rises in head just before subsidence were observed in piezometers constructed in low-permeability units. Although the initial phase of subsidence is considered dilational, these head increases indicate compressional effects that raise pore-water pressures. Possible mechanisms are shear stresses at the leading edge of subsidence or transmission of stress related to dewatering of underlying permeable units.
Publication type Article
Publication Subtype Journal Article
Title Anomalous increases in piezometric levels in advance of longwall mining subsidence
Series title Environmental & Engineering Geoscience
DOI 10.2113/gseegeosci.V.4.407
Volume 5
Issue 4
Year Published 1999
Language English
Publisher Environmental Engineering Geologists
Description 11 p.
First page 407
Last page 417
Google Analytic Metrics Metrics page
Additional publication details