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The Ancient Volcanic Rocks of South Mountain, Pennsylvania

Description: From introduction: In December, 1892, as the result of field work on the part of Dr. G. H. Williams in the northern and of the writer in the southern portion of South Mountain, there appeared a preliminary description of two of the rock types, in which their identification as ancient volcanics was announced. In this bulletin it is proposed to substantiate that identification with more detailed proof. It is further proposed to show that these ancient igneous rocks were, at the time of their cons… more
Date: 1896
Creator: Bascom, Florence
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The Cambrian Rocks of Pennsylvania

Description: From introduction: In his report on the Geology of Pennsylvania,' Professor Lesley summarizes his opinion upon the geology of the South Mountains and Formation No. 1. In this, Formation No. 1 is referred to the Upper Cambrian, and a detailed description is given of its occurrence along the South Mountains and across the State to the Delaware. The superjacent limestone, No. 2, is referred to the Ordovician.' Fuller reference will be made to Professor Lesley's descriptions in speaking of the rock… more
Date: 1896
Creator: Walcott, Charles Doolittle
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The Colorado Formation and its Invertebrate Fauna

Description: From preface: The following review of one of the Upper Cretaceous faunas as developed in the interior region of the United States has grown out of the study of a collection of fossils found by me in Huerfano park and adjacent localities in southern Colorado. This collection, the greater part of which was obtained during the summer of 1890, proved to be especially interesting because it afforded data for the closer correlation of certain Cretaceous strata in Utah with those east of the mountains… more
Date: 1893
Creator: Stanton, Timothy W.
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The Constitution of the Silicates

Description: A report about silicates which form nine-tenths of the earth's crust and are therefore of fundamental importance to geological changes. The report discusses analyzing them by finding out where they came from and what they are comprised of.
Date: 1895
Creator: Clarke, Frank Wigglesworth
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Correlation Papers: Cambrian

Description: From outline: This work is a review, by one who is working in the Cambrian field, of the work of his predecessors, and of the results they and he have thus far obtained as he interprets them. It thus becomes historical and descriptive, and is a general statement of the principles upon which the correlations have been made in establishing the group.
Date: 1891
Creator: Walcott, Charles Doolittle
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Correlation Papers: Cretaceous

Description: From outline: The primary object of this bulletin is the presentation of a summary of our present knowledge of the North American Cretaceons and a discussion of the system as it is developed on this continent, discussion of or direct reference to the details of the system as it is developed in other parts of the world being omitted.
Date: 1891
Creator: White, Charles A.
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Correlation Papers: Eocene

Description: From outline: This essay comprises, first, a general discussion of the limitations of the term Eocene as employed in American geology. The two-fold character of the Tertiary (1. Eocene, 2. Neocene) in America is insisted on. After a somewhat extended review of the literature, in which the various opinions upon disputed points are especially considered, a general study of the stratigraphical, paleontological, and topographical characteristics of the Eocene in the various portions of the country … more
Date: 1891
Creator: Clark, William Bullock
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Correlation Papers: Neocene

Description: From outline: This paper, after discussing general principles connected with the study and description of the Tertiary or Cenozoic rocks and fossils contained in them, takes up the Neocene deposits of the United States in particular. A chapter is devoted to a summary of what is known in regard to the Neocene of the eastern coast of the United States, each State in geographical order being separately considered, beginning at the north.
Date: 1892
Creator: Dall, William Healey & Harris, Gilbert Dennison
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The Death Valley Expedition: A Biological Survey of Parts of California, Nevada, Arizona, and Utah, Part 2

Description: Collection of reports on Death Valley, the bordering region of California, Nevada, Arizona, and Utah. Reports include birds, reptiles and Batrachians, fishes, insects, mollusks, trees and shrubs, cactuses and yuccas, and list of localities in the reports.
Date: May 31, 1893
Creator: Fisher, A. K.; Stejneger, Leonhard; Gilbert, Charles H.; Riley, C. V.; Stearns, R. E. C.; Merriam, C. Hart et al.
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The Devonian System of Eastern Pennsylvania and New York

Description: Introduction: By way of introduction a section will be described across the Devonian of the northeastern part of Monroe County, Pa., along the line of Brodhead Creek and the Delaware, Lackawanna and Western Railroad. The base of this section will rest on the Corniferous limestone well exposed in a railroad cut a mile south of East Stroudsburg and the termination will b6 in the Pocono, as exposed on the Pocono Mountains, from Mount Pocono to the ridge northwest of Tobyhanna.
Date: 1894
Creator: Prosser, Charles S.
open access

A Dictionary of Geographic Positions in the United States

Description: From introduction: For several years the Division of Topography of the United States Geological Survey has been engaged in compiling positions determined within the United States which are believed to be of sufficient accuracy for use in the preparation of its maps. This compilation has been found extremely useful in the office, and it is believed that its usefulness will be greatly extended by placing it before the public. This list comprises between 9,000 and 10,000 positions. To publish it i… more
Date: 1895
Creator: Gannett, Henry
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