Abstract

Holocene sediments from the Brazos River point bar near Wallis, Texas, and from marginal marine settings along the Gulf Coast of Texas between Galveston and Freeport were analyzed to document the surface texture of near-surface framework grains. The purpose was to determine whether or not textures exist that resemble textures formed during deeper burial. The samples range from subarkoses and sublitharenites to quartz-rich lithic arkoses and feldspathic arkoses. Many feldspar grains, particularly K-feldspars, show extensive dissolution textures that either are inherited from the source area, developed during transport, or are forming at the present time. Also, quartz grains with slightly abraded quartz overgrowths, and detrital grains with clay coats and "bridges" were observed. These features, if observed in samples from deeply buried sandstones, could be misintepreted to be the result of diagenesis during the current cycle of burial. In light of these observations, caution should be used in the interpretation of the time of formation of diagenetic textures, particularly dissolution textures that are commonly categorized as contributing to secondary porosity. The determination of exactly where and when these textures formed was beyond the scope of this study.

First Page Preview

First page PDF preview
You do not currently have access to this article.