| ABSTRACT
Sandstones of the Bone Spring
formation (Leonardian) with significant potential in the northern portion
of the Delaware basin include the Avalon sandstone and third Bone Spring
sandstone intervals. The Avalon sandstone is a very fine to fine-grained
submarine-fan deposit, 10-18 m thick, distributed across parts of southern
Eddy and southwestern Lea counties, New Mexico. The Avalon consists of
a series of individual sandstone zones separated by carbonaceous and shaly
siltstones. The sandstone zones display moderate porosities (7-17%) and
low permeabilities (0.5-7.2 md) and require artificial stimulation to produce.
Net pay is commonly 4-8 m. Reserves per well seldom exceed 100,000 bbl,
and the Avalon interval is considered a secondary reservoir.
The third Bone Spring sandstone is widely
distributed across the northern Delaware basin and is especially prospective
within the deeper basinal area to the east. In contrast to the Avalon sandstone,
which was sourced from the north and northwest, submarine-fan systems of
the third Bone Spring sandstone were supplied from the northeast and east,
with detritus derived from the Central Basin platform (CBP). Productive
sandstone zones are very fine grained channel and levee/overbank facies,
with porosities of 7-18% and permeabilities of 2.0 md or
©Copyright
1997. The American Association of Petroleum Geologists. All rights reserved. 1Petroleum
Consultant, 1511 18th Avenue East, Seattle, Washington 98112.
I
thank the following companies and individuals who helped make this paper
possible: Larry Brooks, Parker and Parsley, for data and expertise related
to all aspects of the study; Mike Hayes, Yates Petroleum; Ralph Worthington;
and Floyd Bardsley for artwork. Send reprint
requests to AAPG Publications Manager, P.O. Box 979, Tulsa, Oklahoma 74101-0979.
k = thousand,
M = million, G = billion. | 
