Patent ID: 8811776
Filing Date: 2014-08-19
Classification: E21B,G01K

Abstract:
1. A method for measuring a physical parameter at a plurality of spaced apart locations in a subterranean formation, the method comprising: a. inserting into a well extending into the subterranean formation an elongated sensing element, the elongated sensing element including: ii. an optical fiber in the jacket defining an optical path through the plurality of locations, the optical fiber having an excess fiber length EFL at 20 degrees C., the optical fiber having a coefficient of thermal expansion CTE  the elongated sensing element having a parameter of at least 1 mm 2 per percent of EFL; b. injecting an optical signal in the optical fiber, the optical fiber producing a response to the optical signal that is dependent on the localized dimensional changes and conveys information about the physical parameter at the plurality of spaced apart locations; processing the response to derive information about the physical parameter at each of the plurality of spaced apart locations.