List of Plates and Figures
FIGURES
Figure 1 Physiographic map of the Union Furnace area
Figure 2 A portion of the Digital Shaded-Relief Map of Pennsylvania
Figure 3 Generalized stratigraphic column
Figure 4 Generalized cross section of the Ridge and Valley and Appalachian Plateau
Figure 5 Simple Bouger gravity map of Pennsylvania showing the trend of the Tyrone-Mt Union lineament
Figure 6 Trenton and deeper wells in Pennsylvania
Figure 7 Lithostratigraphic correlation diagram for uppermost Cambrian and Ordovician rocks in the central Appalachian basin
Figure 8 Late Ordovician paleogeography
Figure 9 Paleoceanography of Earth during the Late Ordovician
Figure 10 Ordovician stratigraphic column for central and western Pennsylvania
Figure 11 Ancient Appalachian tectonic subsidence history
Figure 12 The Deicke K-bentonite
Figure 13 Interpretation of carbonate facies in the Coburn through Loysburg Formations
Figure 14 Carbonate ramps
Figure 15 Modern homoclinal carbonate ramp environments
Figure 16 Landsat image of northern Yucatan, Mexico
Figure 17 Measured Trenton and Black River section along PA 453
Figure 18 Legend for symbols used in the stratigraphic diagrams
Figure 19 Hardgrounds exposed near Bimini
Figure 20 Effects of sea level variations on carbonate sedimentation, hardground formation, and the development of vertical sedimentary successions
Figure 21 Morphological classification of hardgrounds
Figure 22 Hardgrounds of the Hatter Formation
Figure 23 Undercut to pebbly hardgrounds in the Linden Hall Formation
Figure 24 Reworked hardground in the Linden Hall Formation
Figure 25 Nodular bedding in the Nealmont Formation
Figure 26 Generalized geologic map of the Altoona-Tyrone area
Figure 27 Cross section A-A’
Figure 28 Geologic map of the Tyrone-Union Furnace area
Figure 29 Orientation diagrams for structures in the Union Furnace area
Figure 30 Photographs of Union Furnace quarry
Figure 31 Photographs of Union Furnace quarry geologic structures
Figure 32 Arch Spring
Figure 33 Map of Tytoona Cave
Figure 34 Stalagmites and stalactites in Tytoona Cave
Figure 35 Soda straw stalactites in Tytoona Cave
Figure 36 Two views of Arch Spring
Figure 37 Entrance to Field Trip Cave along PA 453
Figure 38 Map of Field Trip Cave
Figure 39 Aerial photograph of Route 453, Union Furnace Quarry, and surrounding areas
Figure 40 Alternating dolostone and limestone in the Milroy Member (“Tiger Stripe”) of the Loysburg Formation
Figure 41 Subtidal peritidal facies in the Loysburg Formation
Figure 42 Wavy, flaser, and lenticular bedding, and mudcracks in the Loysburg Formation
Figure 43 Microbially laminated mudstones in the Loysburg Formation
Figure 44 Chert in the Loysburg Formation
Figure 45 Vertical facies successions in the Hatter Formation
Figure 46 Lagoonal carbonate facies in the Hatter Formation
Figure 47 Fossils in the lagoonal facies of the Hatter Formation
Figure 48 Landsat images of Shark Bay, Australia and Yucatan, Mexico
Figure 49 Grainstones in the Hatter Formation
Figure 50 Bioturbated, dark, organic-rich mudstone in the Snyder Formation
Figure 51 Vertical facies successions in the Snyder Formation
Figure 52 Oolitic grainstones in the Snyder Formation
Figure 53 Mixed grainstones in the Snyder Formation
Figure 54 Hardgrounds in the Snyder Formation
Figure 55 Bryozoans in the Snyder Formation
Figure 56 Vertical succession of sedimentary features in the Linden Hall Formation
Figure 57 Hardgrounds in the Linden Hall Formation
Figure 58 Photomicrographs of the Linden Hall Formation
Figure 59 Vertical succession of sedimentary features in the Nealmont Formation and lowermost Salona Formation
Figure 60 Photographs of the Nealmont Formation
Figure 61 Photographs of the Nealmont Formation
Figure 62 Photomicrographs of the lower Nealmont Formation
Figure 63 Photographs of the Salona Formation
Figure 64 Idealized Salona Formation cycles
Figure 65 Photographs of the Coburn Formation
PLATES
Plate 1 Panoramic view of “west” quarry highwall (1996)
Plate 2 Geological map of Route 453 road-cut 27
