P.1. Map of the Big Badlands of South Dakota showing locations of specific places and features discussed in the text. The boundary of Badlands National Park is shown by the heavy dash–dot–dot line. The northern area of Badlands National Park in Pennington and Jackson counties is the North Unit. The base map is from the U.S. National Atlas Web site (http://nationalatlas.gov/mapmaker).
MAKOSICA (MAH-KOH SHEE-JAH) IS THE LAKOTA WORD for “badlands,” or the barren and rough country of buttes and cliffs that are cut by multitudes of deep canyons and ravines. The term badlands does not refer to anything evil about the lands but rather to the difficulty of crossing the country on foot or horse. Modern travelers crossing the Badlands Wall of South Dakota in cars on paved highways do not appreciate the difficulty these landforms posed to early travelers. The French name for this country, mauvaises terres á traverser, “the bad lands to traverse,” was an even more explicit description. In places in Badlands National Park, one can still walk for over 10 km at the base of the Badlands Wall and not find even a game trail that crosses the wall. Nevertheless, the Big Badlands of South Dakota is one of the most spectacular landforms in the United States and is cut in rocks containing some of the most abundant vertebrate fossils of any rocks of the Age of Mammals (Cenozoic Era) in North America. Fossils from the White River Badlands can be found in every major natural history museum in the world. Badlands National Monument (later Badlands National Park) was established to protect the unique landforms of the White River Badlands and the “vast storehouse of the biological past” (Badlands National Park, Statement for Management, 1992).
The Badlands, with a capital “B,” represents the Badlands of Western South Dakota; it is a place-name and the original basis for the geomorphic term. The word badlands has entered the geological vocabulary (when written in lowercase) as a geomorphic term describing a highly eroded landscape with little vegetative cover in arid to semiarid climates. Within the context of this book, badlands in this sense is used as a generic descriptive term as any topographic area that meets these criteria. The terms White River Badlands, Big Badlands, or just the Badlands will be used interchangeably throughout the text to refer to these exposures throughout southwestern South Dakota. The Big Badlands of western South Dakota is unquestionably the most famous of all the areas around the globe referred to as badlands, and it is certainly the most prolific in terms of fossils that have been collected and placed in museums. The White River Badlands represents all the badlands within the White River drainage basin of western South Dakota and Nebraska. This book will focus mostly on the White River Badlands of South Dakota. Badlands National Park is a 244,000-acre National Park Unit established to protect a portion of the White River Badlands, and it is the central focus of this book (Fig. P.1).
Since 1846, with the first scientific report of a partial fossil jaw from the White River Badlands, these deposits have been an important focus of paleontological research. The diversity of fossils recovered by researchers over the past 167 years from strata that span 9 million years of Earth history has provided valuable data on the evolution of North American mammals during the late Eocene and Oligocene epochs. The rocks and fossils from the White River Badlands have also provided valuable information on climate change during one of the greatest global drops in temperature during the Cenozoic. This climatic change contributed to the evolutionary changes of the fauna and flora and produced major changes in both local communities and the global Eocene/ Oligocene biosphere.
In 1920 Cleophas C. O’Harra published The White River Badlands. At the time he wrote the book, O’Harra was president of the South Dakota School of Mines in Rapid City, but it was as professor of mineralogy and geology at the School of Mines that O’Harra gathered the information upon which his book was based. When White River Badlands was published, it was considered cutting-edge research, and it has been reprinted many times since its initial publication. O’Harra included data collected from the field expeditions of the late nineteenth and early twentieth centuries, including many led by him. As he mentions in his preface, the book was written with the layperson in mind, and since its publication, it has been the definitive work on the geology and paleontology of the Big Badlands in southwestern South Dakota.
The goal of our book is to build on the foundation laid by O’Harra and, like O’Harra, we summarize the research conducted by many geologists and paleontologists (including the authors) that took place over the decades after his contribution. We continue in the spirit of White River Badlands by directing our text to the many enthusiasts, both amateur and professional, with an interest in the geology and paleontology of the Big Badlands. Recognizing that this diverse audience also reflects a diversity in the amount of formal training in geology and paleontology, we have tried to provide general summaries of the subject matter, specific information, and detailed lists of references and glossaries with the sincere hope that this book will serve as a gateway for those who wish to investigate further. This book provides a broad overview of the geology and paleontology of the Badlands, and we urge all of those with a strong interest to pursue the primary literature upon which this book is based.
This book is not primarily intended as a textbook, although it could certainly serve as a supplemental text for a class on local geology or paleontology. It is a synthesis that provides the reader with a solid introduction to a classic geological area based on the research that has been completed by multiple researchers over the last 167 years. We assume that the reader has a basic background in geology and paleontology and an avid interest in the White River Badlands. As our understanding of the diversity and taxonomy of the fossils has evolved, our concepts of the geology have also evolved. Some new stratigraphic concepts have been introduced without a previous published record. These are based on many years of fieldwork and research in the Badlands by some of us. Those familiar with the geology of the Big Badlands may encounter differences in the geologic interpretations.
As a result of the enormous amount of information relating to the geology and paleontology of the White River Badlands that has been published since O’Harra’s original 1920 volume, it became obvious that certain limits had to be set. The area-level scope of the current book encompasses most of the published record of paleontological localities within Badlands National Park and extends in a 100-mile radius, with Cedar Pass as the center (Fig. P.1). The only exception is chapter 7, “The Big Badlands in Space and Time,” which compares the central features of this book with areas similar in age in the western United States and around the world. The temporal scope of this project is limited to the late Eocene and earlier Oligocene epochs, with only minor discussion of pre-Eocene geology and regional geologic history in order to establish a framework for discussion.
Chapter 1, “History of Paleontologic and Geologic Studies in the Big Badlands,” explores the history of science as it relates to the original discoveries and surveys of the White River Badlands and the individuals who have contributed to our understanding of the geology and paleontology of this area. It also discusses many of the early interpretations of how the late Eocene and Oligocene rocks in this area were deposited and how our understanding of this region has changed as the science of geology has matured.
Because a working knowledge of the regional geology is critical to understanding the fossil record and provides the primary context within which fossils are preserved, it is covered in three different but complementary chapters.
Chapter 2, “Sedimentary Geology of the Big Badlands,” outlines the depositional environments and sediment sources which produced the rocks included today within the White River Badlands. Each formal rock unit within the White River Group will be described in great detail. Within the science of geology, it is crucial to be able to recognize individual rock units and correlate them across broad expanses. A preliminary discussion of the Sharps Formation within the Arikaree Group will also be discussed.
Chapter 3, “Paleoenvironmental and Paleoclimatic Interpretations from Paleosols,” explores the process in which paleosols (ancient soils) were formed and preserved in the Badlands and what role they play in interpreting ancient environments and climate. This chapter also summarizes much of the paleosol research that has been completed since 1983.
Chapter 4, “Postdepositional Processes and Erosion of the White River Badlands,” examines the post-Oligocene geologic features of the White River Badlands. Many of the features now exposed in the White River rocks were formed after burial of the sediments and while they were turning into sedimentary rocks (diagenesis). About 5 million years ago, the major geologic processes in this area switched from depositional to erosional, eventually creating many of the famous landforms in the Big Badlands of today. Faulting associated with post-Oligocene extensional tectonics in the Great Plains has had a profound impact on the preservation and distribution of Cenozoic rocks the White River Badlands. Finally, although wind played a large role in the origin of the White River rocks millions of years ago, it still has a role in forming sand dunes across the region and redistributing the ancient dust into the agricultural fields of eastern South Dakota and Iowa.
By far the most significant scientific features of the Big Badlands are its fossils, primarily mammal fossils. The next two chapters introduce the fauna and discuss how the fossils accumulated across the ancient landscapes of the White River Badlands.
Chapter 5, “Bones That Turned to Stone: Systematics,” focuses on the fossil plants, animals, and trace fossils of the White River Badlands. These discussions are based on the published record of body and trace fossils found in and around Badlands National Park, with our discussions organized as genera, including seven invertebrates, one fish, one amphibian, 14 reptiles, seven birds, and 88 mammals. This chapter is written in the style of a field guide so that the reader has a summary of important features to identify a particular fossil at the genus level. This chapter also includes photo plates of many of the fossils from the White River Badlands and the diagnostic features that help with identifications. Important aspects of the evolution and paleoecology of individual taxa are also discussed.
Chapter 6, “Death on the Landscape: Taphonomy and Paleoenvironments,” explores the interrelated nature of fossil preservation and paleoenvironments, as well as how scientists can extract data from the rocks and fossils in order to interpret the paleoforensics of fossil bones. Two important fossil localities in Badlands National Park are used as examples to highlight the interdisciplinary nature of this research, and general discussions are provided of fossil distribution and controls on the fossilization process.
Chapter 7, “The Big Badlands in Space and Time,” places the White River Badlands into a larger context. We explore global events that occurred during the late Eocene and Oligocene epochs, and how ancient records from across the globe can be combined in order to develop an overall picture of paleoclimatic change during this critical interval of Earth’s history.
Chapter 8, “National Park Service Policy and the Management of Fossil Resources,” focuses on the management of paleontological resources at Badlands National Park. This chapter explores ongoing park projects and how we protect fossil resources, and the interface between the visitor and the abundant fossil resources – something unique to Badlands National Park.
