- Deep Time and the Texas High Plains: History and Geology
Paul H. Carlson tackles an admirable but daunting task—explaining in only 117 pages how geological forces shaped history over the course of more than ten thousand years at an archaeological site and its surrounding region on the Texas High Plains. Drawing upon John McPhee's concept of "deep time," the author proposes to capture the "long geological past" of the Lubbock Lake archaeological site located in northwest Texas's Llano Estacado region (p. xv). At times, the vast scale and scope of change Carlson describes overwhelms the narrative and prevents him from focusing sufficiently on the Lubbock Lake site or even the Llano Estacado.
Carlson sets a context of "deep time" by starting with the Big Bang approximately ten to fifteen billion years ago. He briefly surveys the evolution of stars, the Earth's internal structure, and the geologic time scale. "Then, over deep time, the great Pangaea separated" (p. 6). As geological processes formed different rocks, dinosaurs appeared and became extinct and mammals evolved. By the end of chapter one, the author has surveyed the prehistoric past up to approximately ten thousand years ago. The scope and impact of the change Carlson covers is so all-encompassing and global in its reach that the reader is left to wonder whether the author has provided too much context.
Paleoindian cultures provide the subject matter for the next chapter, and here too the author struggles to strike a balance between generalizations about pre-Clovis, Clovis, and Folsom cultures and more specific assertions about choices people made accommodating their lives to the Lubbock Lake and Llano Estacado environments. Although archaeologists have uncovered extensive evidence of these cultures throughout North America, it is never entirely clear what lessons Paleoindians' lives illuminate for the modern reader about this particular environment which, after all, purports to serve as the book's focal point.
Carlson does a better job of characterizing the impacts of long-term climate and environmental change on the Llano Estacado's people and land in chapter three, [End Page 417] which focuses on the Archaic period (8,500 to 2,000 years ago). Due to a semi-arid interval of time, animals dependent on the region's water supplies departed as vegetative cover gradually decreased at the Lubbock Lake site. People continued to use the site, though, to camp and gather plants. Carlson is on shakier ground when he characterizes social organization during the Archaic period. For example, he states that sharing, egalitarianism, and flexible social institutions "must have been present" and acknowledges that he can only "speculate" about mobility patterns (p. 65).
The next two chapters cover the period from two thousand years ago to the present. Carlson discusses rather informatively and adroitly the process by which Indian people branched off into separate cultural groupings, contested one another for access to the area, and felt the impact of Europeans entering the area. He then narrates Americans' attempts to hunt bison and ranch the area, their impacts on the local environment, and archaeological activity that has uncovered much of the information that makes up this study.
Historians should produce more studies of the kind Carlson has tackled. Geology significantly shapes history by defining the limits of the stage upon which environmental, biological, and human events unfold. The relationships between geology and history are manifold and complex, and Carlson unflinchingly sets out to articulate how the two intersect. This approach presents the Herculean task of identifying how the grand sweep of geological time unfolded in smaller regions and local environments in ways readers can comprehend.