ROUGH AND TUMBLED — THE GEOHERITAGE SIGNIFICANCE OF OGALLALA FORMATION QUARTZARENITE CLASTS IN NORTHWESTERN TEXAS

Ogallala Formation quartzarenite clasts (referred to as Potter member quartzite in the archaeological literature) are a very well-indurated quartzose sandstone that is abundant in the basal gravels of the Ogallala Formation and occurs as gravel outcrops across the North American Great Plains region. Currently, these quartzarenite cobbles have neither economic nor heritage value. Yet, these cobbles are a significant source of material for crafting stone tools and were used as hearthstones in thermal features by prehistoric peoples across the Great Plains of North America. On-going field research along the eastern escarpment of the Southern High Plains near Post, Texas, has documented Potter member quartzarenite outcrops and associated prehistoric workshop and campsite localities. Results of this work reveal the geoheritage significance of Potter member quartzarenite nodules and the importance of research to identify geoheritage from the past.