Locating Abandoned Mines Using the Active Mining Operation as the Seismic Energy Source – Demonstration of a New Method
This study demonstrates a new method for detecting the margin of old mine works using the seismic energy generated by active mining in the coal seam. As the first test of this new concept, the method should not be viewed as a proven, off-the-shelf technology, but rather a demonstration of the fundamental concept which has promise for detecting the margins of old mine works. For the primary method a linear spread of vertical 4.5Hz geophones on the earth’s surface was distributed across the margin of old mine works (both flooded and air-filled locations) and to a position over the active mining nearby. The seismic vibrations associated with the underground mining were passively recorded across this spread, with individual records as long as 32 seconds. Through a process of crosscorrelation, using each seismic trace sequentially as the pilot sweep for correlation with each other trace in the recording, two distinct seismic wave arrival patterns emerged from the data. The direct arrival from the mining operation to the surface through the rock overlying the coal seam was distinct and well represented in
A Coal Seam as a Guide for Seismic Energy
A DISPERSIVE train of vibrations resembling an internal Love wave has been observed during seismic experiments in the Mangapehi State Coal Mine, New Zealand. The observation is of interest as suggesting that coal mines may offer peculiarly favourable conditions for the study of this type of wave, and also because guided waves may find useful applications in mining.
Communist History: An Annual Bibliography (2005)
The subject of this bibliography is the scholarly literature of communist history. For the USA coverage is extensive. For the rest of the Anglophone world coverage is selective, while coverage for the rest of the world is more selective still. Coverage of the former and presently communist countries is largely limited to works dealing with the Communist parties of those countries. Anti-communism is covered selectively, with somewhat more emphasis on its interaction with communism than its nature as a movement/ideology per se. Coverage of related topics, i.e. the labor movement, Marxism, other strains of radicalism, etc., is highly selective and limited to items directly relevant to communism. For coverage of current reportage (newspapers, news weeklies, journals of opinion, Internet/WWW discussion lists, etc.) see the Newsletter of the Historians of American Communism and the Historians of American Communism Discussion List (h-hoac@h-net.msu.edu). The Bibliography is organized into seven sections, listed below. Sections 1–5 are form and genre based (monographs, serials, etc.), while sections 6 and 7 are format based (sound and visual, electronic). Entries are arranged alphabetically within each section. Where the number of entries warrants it, a section is divided into USA and Other. There is no index. Please be aware that most citations for items in electronic format are listed under their appropriate form/genre, i.e. articles in electronic serials are listed under serials. Section 7 (Internet, WWW, etc.) only contains citations for items in forms and genres irreducibly unique to the electronic environment, i.e. discussion lists (and postings and threads therein) and for those web sites and other electronic resources not subsumed under categories 1–7. Items cited are from the calendar year in the title of the Bibliography, with two exceptions, Internet/WWW items, where publication/creation date information is often unavailable or indeterminate, and older items not cited