00000nam 2200000za 4500 9.841168 CaOODSP 20221107152024 cr ||||||||||| 170808s1965 oncabd ob f000 0 eng d CaOODSP eng eng fre n-cn--- M34-20/75E-PDF Larocque, G. E. A sonic system for the determination of 'in situ' dynamic properties and for the outlining of fracture zones [electronic resource] / by G.E. Larocque. [Ottawa : Queen's Printer, 1965] iv, 23 p. : charts, ill., map Technical bulletin ; TB 75 Caption title. Imperfect copy: cover missing. Digitized edition from print [produced by Natural Resources Canada]. Includes bibliographical references. "A sonic system is described which has been developed for probing the rock around mining openings. With this system, transit time measurements of a few hundred microseconds to many milliseconds can be made with an accuracy of 5%. The sonic apparatus is relatively portable and entirely independent of external power requirements, allowing its use in remote mining locations. A hammer blow is used as a source of signal. For transit time measurements between boreholes, hydraulically wedged transmitting and receiving units have been developed; receiving units for application on rock faces have also been developed and used. The basic assumption on which sonic transit velocity is related to fracture zone is stated and some of the possible applications of such measurements are outlined. Field measurements to substantiate some of the statements made are also included"--Abstract, p. i. Includes abstract in French. gccst Mining industry Canada. Natural Resources Canada. Canada. Mines Branch. Technical bulletin (Canada. Dept. of Energy, Mines and Resources. Mines Branch) TB 75 (CaOODSP)9.834857 PDF 1.69 MB https://publications.gc.ca/collections/collection_2017/rncan-nrcan/M34-20/M34-20-75-eng.pdf 299962