Stratigraphy and Paleontology of the Eagle Formation in Montana and Adjacent Areas

A conspicuous two hundred and fifty foot sandstone of central Montana, known as the Eagle Formation, constitutes part of the some five thousand feet of Cretaceous sediments in the state. It stands out in steep cliffs which stretch for many miles in the outcrop area from Wyoming to Canada.

Distribution and Lithology of Sedimentary Rocks in Montana and Adjacent Areas

The general features of the sedimentary rocks in a region, their distribution, and the relationships of these rocks to other rocks of the area and of adjacent areas, are some of the things in which most geologists are interested, for reasons of general curiosity or for obtaining a better understanding of their specific prob­lems

Isopach Maps and Discussion of the Ordovician and Devonian of Montana and Adjacent Areas

The intensive postwar search for new petroleum horizons has resulted in widespread prospecting in the northern Great Plains. No commercial production has as yet been derived from Ordovician or Devonian rocks in Montana, but the relat­ively few tests that have penetrated to critical depths have disclosed encouraging conditions which merit further consider­ation, especially in Devonian strata.

A Discussion of the Geology and an Isopach Map of the Pennsylvanian System in Wyoming and Adjacent Areas

Pennsylvanian strata in Wyoming and adjacent areas have been the subject of much work and discussion. Most of the work has been due to the economic importance of the system as an oil producer in this region. Oil production from strata of Pennsylvanian age is rather recent history; and therefore, much of the available information is local­ized and incomplete.

An Isopach Map and a Discussion of the Permian in Wyoming and Adjacent Areas

The accelerated post-war demand for petroleum products with resultant high prices and dwindling reserves has spurred producers to an extensive search for new fields and for ad­ditional production in known fields. Exploration and discov­ery is dependent on the collection and correlation of vast amounts of data both in the field and that found in liter­ature.

The Fort Union Formation of Montana and Adjacent Areas

The Fort Union formation is one of the most import­ant and best known geologic formations of the northern Great Plains, and is found lying almost horizontal at the surface over large areas in this region.