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Hollywood Quarry lies about 10 miles west of the DeGray Spillway exposure. The thickly bedded upper Jackfork Formation exposed here is thought to be equivalent in stratigraphic position to the upper part of the DeGray Spillway section. Both lenticular and sheet-like turbidite strata, as well as minor, high-angle faults, are exposed. Beds may have originated in a middle submarine fan channel. Laterally discontinuous strata in the upper part of the south wall, highly faulted but more laterally continuous beds in the west wall, and thick, lenticular sandstone beds and pebbly sandstone beds in the east wall comprise the important turbidite features in this quarry. Lenticular, fining and thinning upward conglomerate layers in the lower 88' of section define paleo-channels. In the upper 55' of the channel-fill sequence, prominent rust stains and large, vertical water escape channels may be observed in the sandstone beds. Muddy sandstone units in the upper part of the quarry appear to represent dilute debris flows or slightly cohesive slurries that may be the result of small slumps on submarine slopes. These units are easily distinguished from the cleaner turbidite sands. |
 Click for Larger View. Martin explains relationships of turbidite strata.  Click for Larger View. Group examines a thick, clean channel sand and one of the many minor, high angle faults. | ||
 Click for Larger View. Fossil plant - a species of Lepidodendron.
 Click for Larger View. Channel sands overlain by distal/layered sheet sands (?abandoned channel fill). |
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