Estimating properties of a subterranean formation

Abstract

Extracting a core sample from within a wellbore is optimized based on information extracted from acoustic signals that are generated downhole. The acoustic signals provide an indication of the formation being cored, which is used to obtain or adjust designated coring operating parameters for accomplishing an efficient and effective coring procedure. Coring operating parameters that are adjusted include weight on bit and bit rotational speed. Optimizing coring operating parameters reduces wear on the bit and produces samples with less fractures. Generating acoustic signals is done by the operation of coring itself, or contacting the formation with a coring bit. Contacting includes impacting the coring bit radially against the wellbore's sidewall, or moving the bit laterally after coring operations have initiated.