ALEXANDRIA, Va., April 21 -- United States Patent no. 12,607,119, issued on April 21, was assigned to JAPAN PETROLEUM EXPLORATION Co. LTD. (Tokyo) and TOHOKU UNIVERSITY (Miyagi, Japan).
"In-situ stress measurement method" was invented by Takatoshi Ito (Sendai, Japan) and Tetsuya Tamagawa (Chiba, Japan).
According to the abstract* released by the U.S. Patent & Trademark Office: "A cylindrical side-wall core is acquired from an inner circumferential surface of a well at a predetermined depth from a ground surface. First, second and third measurement cross sections spaced apart in a longitudinal direction of the core are set. In each cross section, the length of the maximum diameter of the cross section where the amount of distortion relativ...