Abstract

In their unique and well-exposed outcrops, Laramide structures of the Wyoming foreland provide an excellent medium for researching and teaching plate tectonics at any educational level from elementary to post-doctoral. In particular, northwestern Wyoming offers an incredible array of Laramide structures and landforms, ranging from asymmetric anticlines, synclines, basins, and backthrusts, to a unique volcanic province, the Absaroka Range. In these structures and landforms, exposed so well in outcrop, students can see firsthand the results of basic mechanisms of compression, extension, strike-slip and tear faulting, and subduction-related volcanism. The generally northwest trend of these primary and secondary structures, seen so clearly on aerial photography, provides students with a better grasp of the direction of plate movements during the Laramide Orogeny. At a higher level of study, these classic structures have fostered fascinating debate about the actual tectonic and lithologic mechanisms responsible for their formation (briefly summarized in this paper), and they continue to do so today. New and evolving technologies are being used to study these structures to assist in oil and gas exploration, groundwater modeling, and geologic mapping. The Owl Creek Mountains/Wind River Canyon, the Bighorn and Wind River mountains, the Bighorn Basin and its many oil-producing anticlines, the Thermopolis Anticline, Sheep Mountain, and the Absaroka Range, are examples of various foreland and late Laramide structures and landforms which can be used to teach plate tectonics at many educational levels.