Abstracts Northeastern Geology and Environmental Sciences Volume 22, Number 4

HENRY SHALER WILLIAMS (1847-1918) AND THE PENNSYLVANIAN PERIOD

William R. Brice
Geology & Planetary Science, University of Pittsburgh at Johnstown, Johnstown, Pennsylvania 15904; [email protected]

ABSTRACT: Although born into a prominent Ithaca, New York, business family, Henry Shaler Williams was destined to follow the academic star and become one of only two North American geologists to create a portion of the Geological Time Scale that is still in use today. After his early education in local schools, Williams matriculated at Yale University in 1864 and stayed there until he completed his Ph.D. in 1871. But for the next several years he worked in the family business, for not until 1879, when he joined the faculty at Cornell University, did his academic life begin in earnest. In his studies at Yale he had concentrated mostly on zoology, with some geological work, so he was well equipped to start detailed stratigraphic analyses of the marvelous Devonian section of Up-state New York, extending and complementing the pioneering work of James Hall. Williams developed the concept of "shifting faunas" which followed local transgressions and regressions. By concentrating on fossil groups, faunules he called them, he was able to recognize faunal zones. As a result of his stratigraphic work, he joined the United States Geological Survey on a part-time basis, and became part of the team producing the Correlation Papers as they were known; very detailed stratigraphic descriptions of geological rocks systems. Williams was given the task of preparing one for the Devonian and Carboniferous Systems published in 1891(USGS Bulletin No. 80). As a result of this study, Williams realized how different the rocks of the Lower Carboniferous of the eastern United States, mostly limestones and almost no coal, are from those of the Upper portion which has most of the coal. These differences led Williams to suggest a special name for the Lower portion, Mississippian Series, a name modified slightly from one coined around 1870 by Alexander Winchell for the strata of the Mississippi River Valley, and the name Pennsylvanian Series was given to the rocks of the Upper Carboniferous based upon Williams' descriptions and stratigraphic work. This new subdivision of the Carboniferous was not immediately accepted, but in 1906, T.C. Chamberlin and R. Salisbury raised these names to Period status, and through the diligence and detailed analyses done by Henry Shaler Williams, North America made a formal contribution to the Geological Time Scale.

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HOYT LIMESTONE OF LATE CAMBRIAN AGE, EASTERN NEW YORK STATE: SPECTACULAR DOMED STROMATOLITES AT LESTER PARK AND PETRIFIED SEA GARDENS

Gerald M. Friedman
Department of Geology, Brooklyn College and Graduate Center of the City University of New York, Brooklyn, NY, and Northeastern Science Foundation affiliated with Brooklyn College, Rensselaer Center of Applied Geology, 15 Third Street, P.O. Box 746, Troy, NY 12181, USA; [email protected]

ABSTRACT: This paper is an extended version of a previous manuscript published in the journal Carbonates and Evaporites. The current paper includes historical aspects of the deposits in Petrified Sea Gardens which have become famous locally as "a fossilized ocean reef". Saratoga Springs, New York, is the site of one of the finest examples of domed stromatolites to be seen anywhere in ancient rocks. Microscopic cyanobacteria, formerly known as "blue-green algae", constructed the stromatolites. The locality is significant in the history of geology as the area where stromatolites were first described and interpreted. These cabbage-head structures, which are part of the Hoyt Limestone of Late Cambrian (Late Franconian to Early Trempeleauan) age, were described by James Hall as early as 1847. Glaciated surfaces expose horizontal sections of the cabbage-shaped heads composed of vertically stacked, hemispherical stromatolites. The microbial heads are discrete domal structures built of hemispheroidal and bulbous stromatolites expanding upward from a base. The heads, many of them compound, are circular in horizontal section, and range in diameter from a few centimeters to a meter. Between the heads are ooids, skeletal fragments of trilobites, brachiopods, pelecypods, and quartz-sand particles.

The earliest reference to stromatolites in this area was that of Steele (1825) whose description included the first reported oolitic limestone in North America among which the stromatolites occur. The depositional environment was that of a peritidal setting involving oolite shoals, lagoons, and intertidal flats.

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"SNOW DUNE EROSION AND LANDFORMS"

Michael Iannicelli
1429 76th Street, Brooklyn, New York 11228

ABSTRACT: Particular relict landforms in the northeast and midwest of the conterminous U.S.A. are reinterpreted here. A series of oval basins in central Pennsylvania are declared as being palsa scars. Palsa scars are oval depressions formed by the thawing and collapse of mounds that consist of unconsolidated material and an accumulation of ground ice. Asymmetrical, linear "steps and risers" that lie close to the basins were formed by a combination of wind- deposited snow and snowmelt erosion (nivation). The same processes are now believed to create the multiple basins which only resemble palsa scars. Symmetrical "fluted topography" (yardangs and linear depressions) in northeastern Nebraska, South Dakota and western Iowa may be correlated to "Budel valleys" by a nival origin instead of by wind erosion (deflation). "Budel valleys", located in Germany, are linear symmetrical and asymmetrical valleys formed by snowmelt from wind-deposited snow. Likewise, the paha of Iowa and Illinois which are isolated ridges standing above lowlands, may have a similar origin. Wind, long considered a minor function within the Pleistocene environment will now play a major role. Ancient transverse snow dunes may be regarded as forming all the linear-type features. Ancient dome, barchanoid-ridge and barchan snow dunes are introduced as the meltwater agents in carving the multiple oval basins and other nival features. A better understanding of this phenomena allows us to make analogies and partial worldwide paleowind and paleoclimatic inferences.

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EATON'S GEOLOGIC MAPPING OF ALBANY AND RENSSELAER COUNTIES: THE BEGINNING OF MODERN GEOLOGIC MAPPING

¹Paul A. Washington and ²Steven A. Chisick
¹Department of Geosciences, University of Louisiana at Monroe, Monroe, LA 71209; [email protected]
²Sevenson Environmental Services, Midwest Division, Merrillville, Indiana 46410

ABSTRACT: Although the representation of geologic data on maps was an obvious outgrowth of the nature of the occurrence of that data, stratigraphy-based geologic mapping did not evolve until Amos Eaton and T. Romeyn Beck mapped the geology of Albany County, New York. The presentation of this map in 1820, along with the completion of a similar map of Rensselaer County, New York by Amos Eaton two years later, was enthusiastically received by the local scientific community and resulted in several other scientists and amateurs in the upper Hudson Valley copying the method immediately and mapping nearby areas (generally political units).

The revolutionary aspect of Eaton's work was that he was engaging in the mapping of stratigraphy in a predefined area, rather than the mapping of a particular facies or lithologic feature wherever it occurs. Prior to this work, geologic mapping in America had either concentrated on the crystalline rocks of particular areas (e.g., Silliman 1810; 1814, 1820; Dana and Dana 1818) or had been facies/lithologic mapping of naturally defined areas (Mitchill 1814a; Hitchcock 1818). Eaton's innovation allowed for the systematic mapping of the geology of large areas containing stratified rocks as the goal of the geologic investigation rather than as a means of studying the stratigraphic system. This approach to mapping seems to have been Eaton's adherence to Alfred Werner's global stratigraphy, with the stratigraphic mapping being a method by which he could locate, and record the distribution of, the elements of this global stratigraphy. The adoption of Eaton's mapping method by American geologists locked in a certain degree of Wernerian thinking (especially layer-cake stratigraphy and lateral stratigraphic continuity) that have strongly influenced the development of the science.

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CRACKING THE CAMBRIAN: WALCOTT IN MARYLAND - 1892

Ellis Yochelson
Research Associate, Department of Paleobiology, National Museum of Natural History, Washington, D.C. 20560-0121, and US Geological Survey (retired)

ABSTRACT: In 1891, Geiger and Keith indicated a Silurian age for a prominent sandstone interval in the stratigraphic section at Harpers Ferry, West Virginia. The following year, field work in southern Pennsylvania and Maryland by C.D. Walcott, accompanied by A. Keith, demonstrated, by Walcott's repeatedly finding fossils, that the presumed Silurian sandstone was of Early Cambrian age. This persuaded Keith of the error at Harpers Ferry. Since that time, the Early Cambrian age of the sandstone unit, later named the Antietam, and underlying clastic sedimentary rocks in the central Appalachians has not been seriously challenged.

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