Reports
Science Quality and Integrity
The USGS provides unbiased, objective, and impartial scientific information upon which our audiences, including resource managers, planners, and other entities, rely.
The USGS provides unbiased, objective, and impartial scientific information upon which our audiences, including resource managers, planners, and other entities, rely.
Browse more than 82,000 reports authored by our scientists over the past 100+ year history of the USGS and refine search by topic, location, year, and advanced search.
Filter Total Items: 83824
Water resources of the Philadelphia district
The area included in the Philadelphia district lies between 39° 45' and 40° 15' north latitude and 75° and 75° 30' west longitude. It has a length of 34.50 miles from north to south and a width of 26.53 miles from east to west, and covers one-fourth of a square degree, which is equivalent, in that latitude, to, about 915.25 square miles. It is mapped on the Germantown, Norristown, Philadelphia, an
Authors
Florence Bascom
Zinc and lead deposits of northern Arkansas
The field work on which this report is based was carried on during the months of July, August, and September, 1902. The writer was assisted by Prof. A. H. Purdue, of the University of Arkansas, and Mr. Ernest F. Burchard. The larger portion of the time was used in the detailed examination and study of the Yellville quadrangle, which is between 36° and 36° 30' and meridians 92° 30' and 93°, and emb
Authors
George I. Adams, A. H. Purdue, E. F. Burchard, E. O. Ulrich
A study of the fauna of the Hamilton formation of the Cayuga Lake section in central New York
No abstract available.
Authors
Herdman Fitzgerald Cleland
Alexandria folio, South Dakota
No abstract available.
Authors
James Edward Todd, Charles Monroe Hall
Bibliography and index of North American geology, paleontology, petrology, and mineralogy, for the year 1902
No abstract available.
Authors
Fred Boughton Weeks
Brownsville-Connellsville folio, Pennsylvania
No abstract available.
Authors
Marius Robinson Campbell
Catalogue and index of the publications of the United States Geological Survey, 1901 to 1903
This catalogue and index are supplemental to those published in 1901 as Bulletin No. 177. These begin where those end; but there will be found in this index some entries—additional and corrective— which refer to papers covered by Bulletin No. 177. The two bulletins constitute a general catalogue and index of the publications of the Geological Survey from its organization, in 1879., to the present
Authors
Philip Creveling Warman
Chemical analyses of igneous rocks published from 1884 to 1900, with a critical discussion of the character and use of analyses
In the first two or three decades of the last century, when the study of rocks as such was being differentiated from that of minerals and of rock terranes that is, when the science of petrogaphy was in its infancy little attention was paid to their chemical features. It is true that a number had been analyzed, but these were for the most part rocks that were of such a character as to lead the inve
Authors
H.S. Washington
Chemical composition of igneous rocks expressed by means of diagrams, with reference to rock classification on a quantitative chemico-mineralogical basis
The value of graphical methods for expressing relative quantities has been well established in all kinds of statistical exposition and discussion. Their use in conveying definite conceptions of relative quantities of chemical and mineral components of rocks is becoming more and more frequent, and the value of the results in some cases can not be overestimated. This is especially true when a series
Authors
J. P. Iddings