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There is some smaller-scale structure to be observed, such as this batch of small crinkles in on of the shale units:

Paleoslump features and fluvial incision in the Conemaugh Group, West Virginia - Mountain Beltway

Another site from the GMU sedimentology field trip in April: An outcrop on Route 33 in Brandywine, West Virginia, showing the Millboro Formation, Devonian - This slab has the brachiopods, too but also seems to contain a few snails (spiral shapes).

Millboro Formation shale in outcrop and in hand sample - Mountain Beltway

Carbonate nodules appear as positively-weathering features in certain horizons:

Carbonate nodules appear as positively-weathering features in certain horizons:

In outcrop:

Millboro Formation shale in outcrop and in hand sample - Mountain Beltway

Turbidites (graywacke & shale) of the late Ordovician Martinsburg Fm, Edinburg Gap, western Massanutten Range, greater Shenandoah Valley, Virginia.  Bedding is slightly flexed from moderately-dipping to more steep, and then back to moderate again. Slickensides on the top of some exposed layers indicate the beds shifted slightly relative to their upstairs and downstairs neighbors: an example of folding through flexural slip. Cleavage here dips to the left, at a steeper angle than bedding.

Turbidites (graywacke & shale) of the late Ordovician Martinsburg Fm, Edinburg Gap, western Massanutten Range, greater Shenandoah Valley, Virginia. Bedding is slightly flexed from moderately-dipping to more steep, and then back to moderate again. Slickensides on the top of some exposed layers indicate the beds shifted slightly relative to their upstairs and downstairs neighbors: an example of folding through flexural slip. Cleavage here dips to the left, at a steeper angle than bedding.

Soft sediment deformation in sandstone and shale, Bolt Mountain

Soft sediment deformation in sandstone and shale, Bolt Mountain - Mountain Beltway

The shale itself looks… like shale. It’s fine-grained, and dark (high carbon content, suggesting low oxygen levels when deposited). It contains articulate brachiopods that are also suggestive of less-than-ideal-conditions-for-animals conditions. Here’s a look down on a bedding plane, for instance:

Millboro Formation shale in outcrop and in hand sample - Mountain Beltway

Raindrop Imprints on Mud Shale

Raindrop Imprints on Mud Shale

Note that the shale above and below is NOT deformed – this is soft sediment deformation rather than tectonic deformation of rock. Look closer:

Millboro Formation shale in outcrop and in hand sample - Mountain Beltway

Sandstone chunk showing cross-bedding and plane laminations:

Sandstone chunk showing cross-bedding and plane laminations:

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