Resource
Potential of Fine-grained Cretaceous Source Rocks,
Gustason, Edmund R.1, Colleen
Sherry2, Marshall Deacon3 (1) El Paso Exploration &
Production, Denver, CO (2) Kerogen Resources, Calgary, AB (3) EnCana Oil &
Gas, USA, Denver,
The Wattenberg Gas Field, in northeastern
Based on an integration of more than 2000
feet of core from several wells, historical production data, wire line logs
from approximately 7000 wells, as well as fall-off injection tests,
microseismic analysis of hydraulic fractures, and production tests in several
new wells, the original 700 feet of potential “gas shales” were reduced to two
intervals, the Niobrara and Greenhorn formations. Although open fractures are
rare, these rocks have high calcium carbonate content and are “fracable”.
Unfortunately, the two most organic-rich and gas-saturated shales, the Sharon
Springs member and the Graneros Shale, have a high clay content and are
difficult to fracture-stimulate. However, they probably form the top and bottom
seals for the Wattenberg shale gas resource play.
AAPG Search and Discover Article #90063©2007 AAPG Annual Convention, Long Beach, California