ABSTRACT: Development of the Austin Chalk in Giddings Field, Burleson County, Texas, by Horizontal Drilling

DRAKE, GERALD E., Union Pacific Resources, Fort Worth, TX

The Austin Chalk produces in a northeast-southwest trend, subparallel to the Texas Gulf Coast, in a band approximately 523 km (325 mi) long and 40-64 km (25-40 mi) wide. Giddings field is located in the central part of this trend and covers a portion of several counties along the productive fairway. The Austin Chalk produces from a hard, dense, intensely fractured limestone with a matrix porosity range of 3-8% and permeabilities of less than 0.01 md. Production comes primarily from the fractures with contribution from the matrix coming later in the life of the well.

Both old and new methods are used for formation evaluation of the horizontal wells. Careful evaluation of the cuttings and close monitoring of the penetration rates and gases are critical in determining if the lateral section is being drilled in the right zone, identifying fractured intervals and in qualifying shows. New borehole imaging tools produce a visual record of the borehole and are good direct measurement indicators of fracturing along the well path. The data gathered from these logs can be used in many ways to aid in evaluation of the play.

AAPG Search and Discovery Article #91014©1992 AAPG GCAGS and GC-SEPM Meeting, Jackson, Mississippi, October 21-23, 1992 (2009)