History of Quartz Cementation in the Lower Cretaceous Travis Peak Formation, East Texas

Abstract

ABSTRACT Quartz is the most abundant authigenic mineral in sandstones of the Travis Peak Formation in East Texas, but the extent of quartz cementation varies widely. To determine major controls on quartz cement distribution, this study used 431 thin sections from 1,100 m of core from 26 wells. Volume of detrital clay matrix is the main textural control on quartz cement. In sandstones lacking detrital clay, no significant correlation exists between quartz cement and grain size, sorting, bed thickness, or sedimentary structure. Depositional facies was an indirect control on quartz cement distribution because facies controlled detrital matrix content, but no significant difference exists between average quartz cement volume in matrix-free paralic (16.7%) and matrix-free fluvial (17.1%) sandstones Quartz cement increases significantly with present depth from an average of 14.6% at 1,825 m to 20.0% at 3,050 m. This trend of increasing quartz cement is interpreted to be the result of 1) an early episode of quartz cementation by meteoric water that resulted in relatively uniform distribution of quartz within the formation, and 2) a later episode related to the development of stylolites that preferentially added quartz cement in the deepest sandstones. Approximately 10 to 20% of the authigenic silica in Travis Peak sandstones was derived internally from intergranular pressure solution and stylolitization; the remaining 80% was imported from unknown sources outside the sandstones.