AAPG Bulletin, V. 83 (1999), No. 5 (May 1999), P. 707-726.

Upper Jurassic Reef Play, East Texas Basin: An Updated Overview: Part 1-Background and Outboard Trend

Scott L. Montgomery,¹ T. Hodge Walker,² Gregory P. Wahlman,² Rick C. Tobin,² and Dan Ziegler³
 

©Copyright 1999.  The American Association of Petroleum Geologists.  All Rights Reserved
 

¹Petroleum Consultant, 1511 18th Ave. East, Seattle, Washington 98112; e-mail: [email protected]
²Amoco Corporation, P.O. Box 3092, Houston, Texas 77253.
³Broughton Operating, 1200 Smith, Suite 1600, Houston, Texas 77002.
 

The work summarized in this article represents the efforts and advice of a number of geoscientists. Acknowledgment is expressed for contributions made by the following individuals: Art Lombard and James Bergen, Amoco Corporation; Phil Clymer, consulting geologist; Jeff Lauman, PI/Dwights; and Neil Turner, consulting geologist. 

ABSTRACT

This paper is the first part of a two-part update on geologic and geophysical characterization of gas-productive Upper Jurassic carbonate buildups in the Cotton Valley limestone of the East Texas basin. Continued exploration in this play has yielded important new information on the nature, timing, and genesis of the relevant buildup features. This information is crucial to an understanding of existing and future productive trends in the play. Recent drilling and discovery have resulted in the identification of two major fairways: (1) an older, outboard (or downdip) trend existing along the distally steepened portions of the ramp, at present-day depths of 16,000-17,000 ft (4880-5185 m), and (2) a younger, inboard (or updip) trend located along the salt-deformed portion of the Late Jurassic ramp system and lying at depths of 14,100-15,300 ft (4300-4666 m). This paper focuses on the outboard trend, with discussion of the inboard trend reserved for part 2. Both articles present core, thin section, and other sample data, as well as seismic information, that together offer the most comprehensive overview of these buildups yet available.