Earth Sciences Commons^™

Classification Of Springs, Kirk Bryan

United States Geological Survey: Staff Publications

Among the common phenomena of nature, springs are notable because of their high usefulness. Since the earliest times the homes of men have clustered around them. In arid regions their number and size may limit the population. In many humid regions springs are so numerous and similar that distinctions between them are not recognized, yet they may be caused by so many principal and minor factors or by so many combinations of these factors as to make the origin of any one spring exceedingly complex or obscure. An interesting account of the many erroneous notions held by the ancients regarding …

Cross-Bedding In The White River Formation Of Northwestern South Dakota, Dean E. Winchester

United States Geological Survey: Staff Publications

Rocks of White River (Oligocene) age have been known for many years to constitute numerous isolated buttes and mesas in the northwest corner of South Dakota, but no detailed study of their character and structural relations had been made until 1911, when, during an examination of the lignite area of that country, the writer had occasion to study the relation of the younger rocks to those containing lignite beds.

Todd, in 1895, recognized the White River formation in the Slim Buttes and called attention to the area in the following language:

3. Miocene beds, both White River and Loup Fork, …

Paleogeographic Maps Of North America, Bailey Willis

United States Geological Survey: Staff Publications

In passing from the Jurassic to the Lower Cretaceous North America underwent but little change along the Atlantic border and throughout the east. It remained a low land and the coastal plain was somewhat more deeply submerged. But on the Pacific coast, on the contrary, there was pronounced movement, particularly in the Coast Range of California. A bold peninsula developed from Oregon south to Santa Barbara and, being eroded, yielded the thick sediments of the Shasta group, which were deposited in marine water east of it, in part.

In Alaska the Shastan sea appears to have invaded the Jurassic land …

On The Origin And Definition Of The Geologic Term "Laramie", A. C. Veatch

United States Geological Survey: Staff Publications

INTRODUCTION

Investigations of the United States Geological Survey during the summer of I906, covering the larger part of the Laramie exposures on the Laramie Plains, examined by the King and Hayden surveys, have revealed many new and important facts bearing on the Laramie problem.

By detailed areal surveys it was found: (1) that the lignitiferous series, which in the Laramie Plains lies between the Montana below and the Fort Union above, and has a maximum thickness of about 12,500 feet, is divided about the middle by an unconformity; (2) that this unconformity is in the same stratigraphic plane and continuous …

The Morrison Formation And Its Relations With The Comanche Series And The Dakota Formation, T. W. Stanton

United States Geological Survey: Staff Publications

The beds now generally designated on U. S. Geological Survey maps as the Morrison formation have been a subject of interest and discussion since I877, when abundant remains of dinosaurs were found in them. The first extensive collections of the vertebrate fauna were obtained in the neighborhood of Morrison near Denver, -in Garden Park, near Canyon City, Colorado, and at Como, or Aurora, Wyoming. Since then the formation has been recognized by means of its fossils, its lithologic features, and its stratigraphic relations in the Black Hills, on the Laramie Plains, and elsewhere in Wyoming, in Montana, in western Colorado, …

The Aerosphere As A Network Connector Of Organisms And Their Diseases, Jeremy D. Ross, Eli S. Bridge, Diann J. Prosser, John Y. Takekawa

United States Geological Survey: Staff Publications

Aeroecological processes, especially powered flight of animals, can rapidly connect biological communities across the globe. This can have profound consequences for evolutionary diversification, energy and nutrient transfers, and the spread of infectious diseases. The latter is of particular consequence for human populations, since migratory birds are known to host diseases which have a history of transmission into domestic poultry or even jumping to human hosts. In this chapter, we present a scenario under which a highly pathogenic avian influenza (HPAI) strain enters North America from East Asia via postmolting waterfowl migration. We use an agent-based model (ABM) to simulate the …