Ames Impact Structure, Oklahoma, Symposium Online As PDF File
The symposium is:
Johnson, K. S., and J. A. Campbell, 1997, Ames Structure in Northwest Oklahoma and Similar Features: Origin and Petroleum Production (1995 Symposium). Proceedings of a symposium held March 28-29, 1995, in Norman, Oklahoma. Circular no. 100. Oklahoma Geological Survey,
The University of Oklahoma, Norman. ISSN 0078-4397
It is at:
A paper about similar oil and gas reservoirs created
by extraterrestrial impacts is "High-Impact Reservoirs"
at https://goo.gl/cDqakL .