MAPPING THE LLANO ESTACADO OF NORTH AMERICA

The Llano Estacado is a commonly recognized physiographic region in North America. Renowned for its remarkably level surface and the towering escarpments along its outer margins, the elevated plains of the Llano Estacado form an immense tableland that stands in high relief at the southern end of the Great Plains. The Llano Estacado is not a complex region but there still remains some uncertainty regarding the precise definition of its boundaries. Early maps of this region generally lacked detail due to the fact that explorers avoided crossing this vast treeless and waterless plain. As a result, early cartographers, working with limited information, often depicted the region as either a blank spot or an amorphous region with poorly defined boundaries. Subsequent state and federal geological surveys conducted during the late 19th century advanced our knowledge of this region and more detailed maps soon followed. At the dawn of the twentieth century, most of the Great Plains had been surveyed and this information was available to cartographers. The quality and accuracy of regional maps have steadily improved throughout the twentieth century thanks to the efforts of numerous skilled cartographers aided by the development of twentieth century technologies, such as aerial photogrammetry, satellite imagery, and other forms of remote sensing. Recognizing that a scientific study of the Llano Estacado region must include a firm definition of its boundaries, a recent attempt has been made by the authors to better define the boundaries of this region.