PAUL, DOUGLAS ROY, Landmark Graphics, Houston, TX

ABSTRACT: Reserve Estimation Techniques Utilizing 3-D Seismic Attributes

In difficult economic climates, reliable petroleum reserve estimation is essential in determining the viability of developing prospective fields and reservoirs. In most instances, the available well information is inadequate to generate a confident reserve estimate. The increased use of three-dimensional (3-D) seismic has significantly increased an interpreter's ability to calculate volumetrics by providing a mechanism in which reservoir structure beyond well control can be more accurately delineated. The use of seismic attributes in combination with structure for volumetric analysis has, however, remained largely underused. The objective of this paper is to illustrate techniques in which 3-D seismic attributes may be applied to reserve estimation through the analysis of several selec ed case studies. These case studies encompass a variety of geological terrains over both onshore and offshore fields in Europe and North America. A brief description of each follows: North Frisco city field, onshore Alabama--highly productive, low-resistivity sand pinching out against granite basement highs; Roar field, Danish North Sea--Cretaceous chalk with seismically identifiable gas-water contact and frequency differentiated reservoirs; Tableland field, onshore Canada--Devonian reef with porosity defined by seismic amplitudes; offshore Gulf of Mexico--clastic reservoirs with salt tectonics in highly faulted terrain; and Intall field, onshore New Mexico--Aeolian sand with anhydritic lenses differentiated on the basis of seismic inversion. In each case, the reserve estimate generated sing seismic attributes will be compared to that generated using a more typical structural approach.

AAPG Search and Discovery Article #90990©1993 AAPG International Conference and Exhibition, The Hague, Netherlands, October 17-20, 1993.