Chromite and Other Mineral Deposits in Serpentine Rocks of the Piedmont Upland, Maryland, Pennsylvania and Delaware (open access)

Chromite and Other Mineral Deposits in Serpentine Rocks of the Piedmont Upland, Maryland, Pennsylvania and Delaware

From abstract: The Piedmont Upland in Maryland, Pennsylvania, and Delaware is about 160 miles long and at the most 50 miles wide. Rocks that underlie the province are the Baltimore gneiss of Precambrian age and quartzite, gneiss, schist, marble, phyllite, and greenstone, which make up the Glenarm series of early Paleozoic(?) age. These are intruded by granitic, gabbroic, and ultramafic igneous rocks. Most of the ultramafic rocks, originally peridotite, pyroxenite, and dunite, have been partly or completely altered to serpentine and talc; they are all designated by the general term serpentine. The bodies of serpentine are commonly elongate and conformable with the enclosing rocks.
Date: 1960
Creator: Pearre, Nancy C. & Heyl, Allen V., Jr.
System: The UNT Digital Library
Index of Generic Names of Fossil Plants 1966-1973 (open access)

Index of Generic Names of Fossil Plants 1966-1973

An index of names of new fossil plant genera found in literature between 1966 and 1973 which is now included in the pendium Index of Paleobotany.
Date: 1975
Creator: Blazer, Anna M.
System: The UNT Digital Library
Bibliography and Index of U.S. Geological Survey Publications Relating to Coal, 1882-1970 (open access)

Bibliography and Index of U.S. Geological Survey Publications Relating to Coal, 1882-1970

A bibliography that lists about 1,300 U.S. Geological Survey publications related to coal and published prior to January 1, 1971.
Date: 1972
Creator: Averitt, Paul & Lopez, Lorreda
System: The UNT Digital Library
Mineral Deposits of Central America (open access)

Mineral Deposits of Central America

From introduction: This report is based on investigations carried on by the Geological Survey (U. S. Department of the Interior) under the auspices of the Interdepartmental Committee on Scientific and Cultural Cooperation (U. S. Department of State) and the Foreign Economic Administration. The function of the last two agencies is presently carried on by the International Cooperation Administration. Roberts is responsible for the text of this report and for the compilation of the geologic map. He was in Central America from January to April 1942 under a program of scientific and technical cooperation with the American Republics sponsored by the Department of State, and mapped manganese deposits in Costa Rica and manganese and antimony deposits in Honduras.
Date: 1957
Creator: Roberts, Ralph Jackson & Irving, Earl M.
System: The UNT Digital Library
Index of Generic Names of Fossil Plants, 1820-1965 (open access)

Index of Generic Names of Fossil Plants, 1820-1965

An index of fossil names between 1820 and 1965. Diatoms, spores, and pollen are excluded from this index.
Date: 1970
Creator: Andrews, Henry N.
System: The UNT Digital Library