Bit By Bit: A Good Seismic Strategy

摘要

(The Geophysical Corner is a regular column in the EXPLORER, edited by Bob A. Hardage, senior research scientist at the Bureau of Economic Geology, the University of Texas at Austin. This month s column is the second of a two-part series on drill-bit seismic technology.)rnLast month, we looked at the concept of utilizing the axial impacts of the rotating teeth of a rotary-cone drill bit as a downhole seismic source, which allows seismic data to be acauired byrnsurface-positioned sensors as a well is being drilled. Poly-diamond crystalline (PDC) bits are now replacing rotary-cone bits in many drilling programs. PDC bits cut rock by a scraping action - not by an axial chiseling action, as does a rotary-cone bit.