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Florence Bascom

Publications and source records attributed to Florence Bascom.

At least 19 recordsLinked to original sources
USGS2014

The pre-Cambrian igneous rocks of eastern Pennsylvania and Maryland

The Blue Ridge and Piedmont geomorphic provinces, topographically distinct but geologically a unit, extend southwestward across eastern Pennsylvania and central Maryland, in a belt with an average width in these States of some 50 miles. In these provinces are exposed the crystalline formations of the Atlantic belt. Gneisses (with sporadic interbedded graphitic schist and marble), quartz-schist, crystalline limestone, and scnlsts, constitute the pre-Cambrian sedimentary series which has been folded, overturned, and overthrust with faulting, to the northwest.

Maryland, Pennsylvania↗
USGS1925

The resuscitation of the term Bryn Mawr gravel

In the course of geologic and physiographic work in eastern Pennsylvania, it has seemed to the writer that the time was ripe for the restriction of the term Brandywine formation, now including presumably both Pliocene and Pleistocene gravels, and the reinstatement of the old term Bryn Mawr gravel for a portion of the divided Brandywine. A brief history of the nomenclature and usage involved will show the grounds for the choice of terms.

Pennsylvania↗
USGS1920

The use of the two-circle contact goniometer in teaching crystallography

The two-circle contact goniometer was devised to supplement the two-circle reflecting goniometer, by furnishing a means for the measurement of medium-sized crystals not provided with sufficiently good reflecting faces for the successful use of the latter instrument. The contact goniometer has however proved itself adapted, in a greater degree even than the reflecting goniometer, to the demonstration of the principles of two-circle measurements, and their relation to geographic and astronomical measurements, and of the relations of normals to crystal faces and to projections, both stereographic and gnomonic. This simple and inexpensive instrument, a description of which is given on the following page, is thus fitted to serve a very important purpose in instructional work in crystallography.

American Mineralogist↗
USGS1904

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, and Chester atlas sheets of the United States Geological Survey. a Each of these sheets represents a tract fifteen minutes in extent each way. This district is in Pennsylyania, New Jersey, and Delaware, and comprises, in whole or in part, ten counties-Bucks, Montgomery, Philadelphia, Delaware, and Chester counties in Pennsylvania; Burlington, Camden, Gloucester, and Salem counties in New Jersey; and Newcastle County in Delaware. A population of nearly 2,000,000 is embraced within these limits. The location and general relations of the district are shown in fig. 1, on the next page. In this paper will be discussed the topography, rainfall, run-off, and stream discharges of the chief hydrographic basins, the geology and water-bearing horizons, and the water power and water supply in relation to its present and future utilization.

Water Supply Paper↗