Conference description unavailable.

Conference description unavailable.

Conference description unavailable.

Conference description unavailable.

Day 1 (Friday morning) for a brief orientation on the geology (emphasizing the stratigraphy, structure and geomorphology) of Nittany Valley, from the Jo Hays look-out on Tussey Mountain. Thereafter Group 1 will proceed on the Shale Hills Critical Zone Observatory for the rest of the morning and relocate at the Pavilion for lunch at nearby Lake Perez. Group 2 will drive onto Huntingdon to examine outcrops of the Marcellus Shale, plumose joints in the Brallier Sandstone, and thin-skinned deformation in the shoaling upwards tidalite cycles of the Wills Creek Formation. Then Saturday groups will be segregated into disciplinary preferences themes of (a) Environmental/hydrogeology or (b) stratigraphy/engineering geology.

The first geological survey of Pennsylvania passed to the right and left of Indiana County leaving it a veritable “nether world” of geology. Since then, the “nether world” has been fleshed out and the 81st Annual Field Conference of Pennsylvania Geologists will highlight Indiana County and adjacent areas, rich in both energy and non-fuel minerals for over 100 years. We will look at past and present environments–warts and all. Stops and preconference trips currently being contemplated include: Johnstown 1889 flood site, Miss-Penn unconformity west of Johnstown, flint clay locales, Blacklick Gorge Geology along the Ghost Town Trail, Loyalhanna Limestone outcrops, a caving trip, local whitewater rafting and an AMD treatment site.

Conference description unavailable.

Ten sites present surficial, bedrock and economic geology, structure and geomorphology of South Mountain, the Great Valley and Blue Mountain, principally in Cumberland County. Of the ten, revisited with new interpretations are four classic sites visited by the Conference (one in 1982 and three in 1991). Five viewed quarries produce sandstone, limestone, shale and colluvium/alluvium. Presented are their diverse economic importance as well as their geologic aspects and interpreted history. Featured at one site are dye tracing of long distance ground water travel to a large springs. Paleontology is a sub-focus at two sites. Viewed respectively at two sites is autochthonous and allocthonous Ordovician Martinsburg sediments and markedly diverse structure. Friday evening banquet topic is the history of 19th century iron mining. Recent geomorphic investigations using LIDAR imagery provide new interpretations that allow reconstruction of Cenozoic paleotopography. Cretaceous lignite recovered in a core will be available for examination.

The tale of two provinces examines the Great Amphitheater of Pennsylvania, the Nippenose Valley of Lycoming and Clinton Counties, inside and out on day one. The floor of this breached anticline exposes the Middle to Upper Ordovician, Bellefonte through Reedsville Formations. Just outside of the amphitheater are great exposures of the Marcellus, Tully, and Mifflintown. The second day is along US Route 15 corridor. There we examine excellent exposures of the stratigraphic succession from the Devonian Brallier/Harrell/Lock Haven into the Pennsylvanian Bloss coal complex of Pottsville/ Allegheny age, only to return back to the Lock Haven. It’s a wild roller coaster ride from Williamsport to the New York border as you cross six “time zones” trying to figure out if it is half past the Devonian or a quarter after the Mississippian.

The Field Conference of Pennsylvania Geologists has in the past visited many sites along the Ordovician-Silurian boundary. The “transitional” contact between Silurian and Ordovician rocks in central Pennsylvania becomes unconformable in eastern Pennsylvania to southeastern New York as the hiatus widens. Following the northeastward decrease in intensity of deformation in the Ridge and Valley through New Jersey, this trip will begin with the high-angle contact between the Tuscarora and Hamburg sequence at the Schuylkill River and proceed for 120 miles along the very low-angle unconformable contact between Lehigh Gap, PA and Ellenville, NY. We will suggest predominant Alleghanian deformation along the contact and, in New Jersey and New York, propose zones of increasing southeastward Taconic deformation away from the contact. We will demonstrate the relative intensities and trends of Taconic and Alleghanian deformation in New York, and will comment on the northeastward dying-out of Alleghanian structures in the Shawangunk Mountains. The perplexing story of events during the Taconic hiatus, lasting perhaps 10-20 million years, will be illuminated by an unusual diamictite in southeastern New York.