Improved drilling of coal measure rocks for underground mine void detection and exploration programs /
- 出版日期：1991.
- 出版者：U.S. Dept. of the Interior, Bureau of Mines,
- 页数：28 p. :
- 出版地：Washington, D.C. :
- 第一责任说明：by Pamela J. Watson, Patrick A. Tuzinski, and John E. Pahlman.
- 尺寸：28 cm.
- 分类号：a477
MARC全文
02h0006590 20090327103515.0 s1991 dcua frb |000|||eng | NGL a477 Watson, Pamela J. Improved drilling of coal measure rocks for underground mine void detection and exploration programs / by Pamela J. Watson, Patrick A. Tuzinski, and John E. Pahlman. Washington, D.C. : U.S. Dept. of the Interior, Bureau of Mines, 1991. 28 p. : ill. ; 28 cm. Report of investigations ; 9370 Includes bibliographical references (p. 11). Mine surveying. ; Abandoned coal mines. ; Coal-cutting bits. ; Polyethylene oxide. aTuzinski, Patrick A. ; aPahlman, J. E. ; q(John E.) Report of investigations (United States. Bureau of Mines) ; 9370. aCN bNGL NGL P 720.66 R29u v9370 ; h1 fqyl0804