ABSTRACT: Episodic Quartz Cementation in the Lower Cretaceous Travis Peak Formation, East Texas

Shirley P. Dutton, Timothy N. Diggs

Quartz is the most abundant authigenic cement in Travis Peak quartzarenites on the western flank of the Sabine arch, but its volume varies significantly. Petrographic, isotopic, and burial history data were used to determine the major controls on quartz cement distribution and the conditions under which it precipitated. Most quartz cement (average 15% of whole-rock volume) precipitated relatively early in the burial history, at depths of 1 to 1.5 km, from meteoric fluids (^dgr¹⁸O = -5^pmil) at temperatures of 55 to 75°C. The meteoric water was probably part of an ascending limb of a deeply circulating regional groundwater flow system. Quartz cement is generally present in greater volumes in sandstones lacking detrital clay matrix. Quartz cement volume in m trix-free sandstones does not vary significantly with grain size, sorting, bed thickness, sedimentary structure, or depositional environment. A slight trend of increasing quartz cement with depth below the top of the Travis Peak may indicate that deeper, older sandstones received more quartz cement during this episode because they were exposed longer to cementing fluids or because of early development of stylolites in the deepest sandstones.

After the initial episode of quartz cementation (Early Cretaceous) and movement on the Sabine arch (middle Cretaceous), a second generation of quartz cement precipitated. Continued burial and development of stylolites preferentially added quartz cement in the deepest sandstones, below 2.4 km. As a result of this second cementation event, quartz cement volume increases significantly with present burial depth from an average of 15% at 1.8 km to 20% at 3.1 km. Approximately 20% of the total authigenic quartz in Travis Peak sandstones was derived internally from silica released by intergranular pressure solution and stylolitization; the remaining 80% was imported from outside the sandstones.

AAPG Search and Discovery Article #91003©1990 AAPG Annual Convention, San Francisco, California, June 3-6, 1990