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18 March 2010
Over on the far right by Chuck Bailey (yellow shirt) you can see the crescent-shaped profile of a river channel (gray color). To the left of that, you can see levee deposits, and beyond that (to the left) crevasse splay deposits and the floodplain (dark red mudstones). This is in the Hampshire Formation, part of the Acadian “clastic wedge.”
Here we are in the Brallier Formation, a Devonian turbidite sequence. Prominent in the middle of this photo is the Bouma “C” horizon with the cross- bedding.
This one is also from the Millboro Formation: itty bitty brachs (not too much oxygen in those depths for building up big body sizes) that have been sheared during Alleghanian deformation.
This photo is from the Millboro Formation: mostly deep water black shale, but with the occasional heavy turbidite coursing in and settling its bulk down on the squishy mud beneath. Some folks on our trip suggested these might be seismites: soft sediment deformation resulting from earthquake-induced vibration.
Nice set of twist hackles on the fringe of this joint face:
Oriskany sandstone, folded into an S-fold, then snapped down the middle!
Hoo-hoo! An anticline in the hanging wall of a thrust fault in the Valley & Ridge. This is the redbeds of the latest-Ordovician Juniata Formation. Lynn Fichter for scale.
This is a nice sample of slicks. On the other side, burrows! I like that: a primary structure on one face, a secondary structure on the opposite side.
Looking north along the Germany Valley, which lies in the core of a breached plunging anticline. The topography is defined by the erosion-resistant ridge of Tuscarora Sandstone. This is the Wills Mountain Anticline. The Tuscarora is Silurian; at the bottom of the valley (core of the anticline), you find Ordovician carbonates.