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Jack B. Epstein

Publications and source records attributed to Jack B. Epstein.

At least 37 records · Page 2Linked to original sources
USGS1996

40Ar/39Ar whole-rock data constraints on Acadian diagenesis and Alleghanian cleavage in the Martinsburg formation, eastern Pennsylvania

A comparison of 40 Ar/ 39 Ar age spectra of whole-rock mudstone and slate samples from the Ordovician Martinsburg Formation at Lehigh Gap, Pennsylvania and stratigraphic and thermal constraints support Alleghanian age for regional slaty cleavage and a late Acadian age for diagenesis in these rocks. Age spectra from mud-stones have a sigmodal shape, with slopes that climb steeply from apparent Mesozoic ages to intermediate saddle regions with Devonian apparent ages, and then climb steeply again to Late Proterozoic apparent ages. The steps with these oldest apparent ages are interpreted to be dominated by late Proterzoic detrial muscovite. The saddle region of the mudstone samples gives very Late Silurian to earliest Devonian ages, which are maximum ages of diagenetic micas and which eliminate a Taconic age for the cleavage. The ages of saddle regions of the slate samples constraining cleavage-forming muscovite is <~375. This is the maximum age of this mica and requires an Alleghanian age for the cleavage. These age constraints are supported by ages of individual mica components calculated with knowledge of the total gas ages and mass fractions of the micas and by predictions from thermal modeling. We conclude that the Taconic orogeny in the Martinsburg Formation in eastern Pennsylvania was a very mild event. Not only is the cleavage in these rocks not Taconic in age, but even the mild (~100C) diagenetic growth of illite was Silurian of younger. Thus the Taconic event in these rocks in limited to loading of lass than about 3 km.

Connecticut, Delaware, Maryland, Pennsylvania, New↗
USGS1983

Mineral resource potential map of the Gee Creek Wilderness, Polk and Monroe counties, Tennessee

The Gee Creek Wilderness comprises 2,493 acres (nearly 4 square miles) in the Cherokee National Forest, Polk and Monroe Counties, Tennessee, about 4 miles (6 km) southeast of Etowah, Tenn., and about 20 miles northeast of Cleveland, Tenn. All of the surface in the wilderness is in U.S. Government ownership; mineral rights on nearly half of the land remain in private ownership. The study area is in the Blue Ridge physiographic province. The major rock types in the wilderness area consist of sandstone, shale, and conglomerate of the Chilhowee Group of Cambrian and Cambrian(?) age. Faulting appears to have controlled the location of minor subeconomic iron deposits, but no potential mineral resources were detected by the present survey. Shales, useful for brick or lightweight aggregate, and sandstone, useful for crushed stone or sand, have little economic interest because these rock types are common throughout the region and are found closer to potential markets. The possibility of natural gas occurring in untested rocks structurally beneath the Chilhowee strata cannot be discounted. No potential was found for any other mineral resource.

Tennesee↗
USGS1980

Geology of the Ridge and Valley Province, northwestern New Jersey and eastern Pennsylvania

The rocks seen in this segment of the field trip range in age from Middle Ordovician to Middle Devonian and constitute a deep basin-continental-shallow shelf succession. Within this succession, three lithotectonic units, or sequences of rock that were deformed semi-independently of each other, have somewhat different structural characteristics. Both the Alleghenian and Taconic orogenies have left their imprint on the rocks. Wind and water gaps are structurally controlled, thus placing doubt upon the hypothesis of regional superposition. Wisconsinan deposits and erosion effects are common. We will examine these geologic features as well as some of the economic deposits in the area. Figure 1 is an index map of the field-trip area, showing the trip route and quadrangle coverage. Figure 2 is a generalized geologic map,

New Jersey, Pennsylvania↗
USGS1974

Geology and mineral resources of the Lehighton and Palmerton quadrangles, Carbon and Northampton Counties, Pennsylvania

The Lehighton and Palmerton 73 1/2-minute quadrangles cover an area of about 112 square miles of diversified terrain in the folded Appalachian Mountain and Great Valley sections of the Valley and Ridge physiographic province in Carbon, Lehigh, and Northampton Counties, Pennsylvania. The Lehigh River and Blue Mountain are the prominent features of the topography. Rock units defined and mapped in the area are the lithified sediments that were deposited in a variety of offshore marine, marine shelf, marginal marine, and fluvial environments associated with two phases of basin filling. The rocks are separated into four lithotectonic units, each deformed semi-independently of adjacent lithotectonic units. Decollements presumably separate the lithotectonic units. Lithotectonic unit 1 consists of about 12,000 feet of slate and graywacke of the Middle and Upper Ordovician Martinsburg Formation. This unit contains mainly asymmetric, similar, and nearly isoclinal folds, with wave lengths of 1,000 to 3,000 feet and amplitudes of 400 to 2,000 feet, formed mainly by passive flow and slip. Lithotectonic unit 2 includes about 3,100 feet of sandstone, siltstone, shale, and conglomerate of the Shawangunk Formation (Ordovician(?) and Silurian), Bloomsburg Red Beds (Silurian), and the lower part of the Poxono Island Formation (Silurian). This unit contains mainly asymmetric and concentric folds, with wavelengths of about one mile and amplitudes of 1,500 to 5,000 feet, formed by flexural slip with minor passive slip and flow. Lithotectonic unit 3 contains about 750 feet of limestone, shale, siltstone, sandstone, and dolomite of the upper part of the Poxono Island Formation, Bossardville Limestone, and Decker Formation (all Silurian), the Coeymans and New Scotland Formations, Shriver Chert, and Ridgeley Formation of the Oriskany Group and the Schoharie-Esopus Formation (all Lower Devonian), and the Palmerton Formation and Buttermilk Falls Limestone (both Middle Devonian). This unit has asymmetric, concentric, similar, and flap folds, with wavelengths of 1,000 to 1,500 feet and amplitudes of about 1,550 feet, formed by flexural slip and flow and passive slip and flow. Lithotectonic unit 4 consists of more than 13,000 feet of sandstone, conglomerate, siltstone, and shale of the Middle Devonian Marcellus and Mahantango Formations, the Upper Devonian Trimmers Rock and Catskill Formations, the Devonian-Mississippian Spechty Kopf Forma tion, the Mississippian Pocono and Mauch Chunk Formations, and the Pennsylvanian Pottsville Formation. This unit contains nearly symmetric, concentric flexural-slip folds with wavelengths of more than five miles and amplitudes of about one mile. Surficial deposits occur throughout the mapped area and include: Pleistocene pre-lllinoian(?) till and outwash(?), lllinoian(?) till and outwash, Wisconsinan outwash, shale-chip rubble, boulder fields, and colluvium; and Holocene alluvium, landslide deposits, and man-made dumps. The rocks of the mapped area, except for the deeply weathered lime stones, generally have good slope stability and foundation support strength, moderate to low primary infiltration capacity and aquifer potential but moderate to high secondary values for these properties, moderate resistance to weathering, and are moderately difficult to difficult to excavate. All of these properties are strongly influenced by the abundant bedding, cleavage, and joint partings of the rocks. Similar evaluations for the surficial deposits indicate less desirable values except for the ease of excavation of most of the unconsolidated materials. Currently active and potential mineral resources are numerous in the Lehighton and Palmerton quadrangles and include slate, sand, paint ore, building stone, crushed rock, lightweight aggregate, clinker residue, clay, hydraulic cement, and roofing granules.

Pennsylvania↗