Rathbun, A.P. (Chevron Energy Technology Company) | Carlson, S.R. (Chevron Energy Technology Company) | Ewy, R.T. (Chevron Energy Technology Company) | Hagin, P.N. (Chevron Energy Technology Company) | Bovberg, C.A. (Chevron Energy Technology Company) | Boitnott, G.N. (New England Research, Inc.)
Elastic properties such as Young’s modulus (E) are key controlling factors in the design of drilling and completion operations in conventional and unconventional reservoirs such as gas/oil shales and tight gas sands. Due to the high cost and long time needed for rock mechanics testing on core, it is not always possible to conduct traditional tests within the time frame from well drilling to well completion operations. In addition, shale cores are often naturally fractured and it can be difficult to acquire plugs. Here, we present a rapid, non-destructive, index method based on impulse for the determination of a coupled E and Poisson’s ratio, v E*= E/(1v2). A small mass (60g) with a spherical tip of radius 3.81 or 38.1 mm is dropped on a flat surface from 12-19 mm. The mass slightly deforms the core and then rebounds from the core. From a combination of Hertzian contacts and Impulse, the elastic properties can be determined from the force-time curve of the impact. Our results are compared against a variety of materials including metals, ceramics, plastics, other synthetics, and a variety of rocks. Using this method, E* can be determined at cm spacing for several meters of core in one day of testing.