Patent ID: 9366122
Filing Date: 2016-06-14
CPC Classification: E21B

Claim Text:
1. A method for estimating a property of an earth formation penetrated by a borehole, the method comprising: performing a borehole integrity test at a pressure less than a fracture gradient pressure of the formation wherein the fracture gradient pressure is a pressure at which pre-existing rock fractures in the earth formation will open and begin to accept fluid, the borehole integrity test providing leakage data, the borehole integrity test comprising injecting a fluid into the formation using a fluid injector at an integrity test flow rate that is low enough so that the fracture gradient pressure of the formation is not exceeded; injecting a fluid into the formation at a first pressure greater than the fracture gradient pressure at a first flow rate during a first injection time interval using the fluid injector; measuring pressure versus time using a pressure sensor and a timer during a first test time interval after the injecting for the first injection time interval to provide first pressure data; injecting a fluid into the formation at a second flow rate greater than the first flow rate during a second injection time interval using the fluid injector; measuring pressure versus time using the pressure sensor and the timer during a second test time interval after the injecting for the second injection time interval to provide second pressure data; monitoring a fluid temperature in the borehole using a temperature sensor; correcting the first pressure data and the second pressure data for fluid temperature variations using the monitored fluid temperature; correcting the leakage data for fluid temperature variations using the monitored fluid temperature; estimating the property using the corrected first pressure data, the corrected second pressure data, and the corrected leakage data using a processor; estimating a hydraulic stimulation pressure to stimulate the formation using the corrected first pressure data, the corrected second pressure data, and the corrected leakage data; and hydraulically stimulating the earth formation using the estimated hydraulic stimulation pressure.