|
| Unit No. |
Description |
Thickness |
|
1
|
Limestone - light gray (N7), hard, wavy and irregularly bedded, very thin bedded, basal contact is gradational with underlying shale. Very fossiliferous including abundant Marksia locally that grade(?) laterally(?) into abundant small Osagia. The Osagia typically very light gray (N8) vuggy, blotchy gray and white limestone with large areas of coarsely crystalline calcite occurs above these algal beds
|
6 ft.
|
|
2
|
Shale - light grayish orange (10YR8/4), calcareous, fossiliferous, the upper inch contains fossils locally, including small brachiopods, crinoid stems, and Trepospira-like gastropods
|
3 ft.
|
|
3
|
Limestone - nodular, medium gray (N5) weather grayish orange (10YR7/4) to pale yellowish borwn (10YR6/2); slightly fossilifrous and of variable clay content. This bed occurs as a layer of unconnected roundish algal(?) bodies that contain angular fragments of light olive gray (5Y5/2) clay shale in their lower portions and a few fossils in other centers. Laterally they grade into a solid bed 0.6 ft. thick that appears to consist in the upper 0.2 ft. of small (0.1 - 0.2 in.) algal pellets amid Chonetina, Hustedia, Punctospirifer, crinoid stem, tec., most of which have an algal coating. (There is some question in my mind whether the shale and algal limestone should not properly be placed in the Stanton limestone on an environmental basis - but for mappability, the base of the Stanton should stop at the base of the Captain Creek as shown.)
|
0.5 ft.
|
|
4
|
Shale - light olive gray (5Y5/2); non silty, unfossiliferous, grades downward into shale below
|
8 ft.
|
|
5
|
Shale - dark bluish gray (5B3/1) non-silty, unfossilifrous that contains near it middle of 0.1 ft. bed of blue gray (5B5/1) very clayey calcareous unfossilifrous concretionary bed seamed with black calcite and, at the top has a similar bed that is apparently not calcareous and about 0.1 ft. thick. Grades downward into shale below
|
10 ft.
|
|
6
|
Shale - light olive gray (5Y5/2), unfossilifrous, slightly silty, finely micaceous locally. Contains several thin beds of ironstone concretions in the upper 60 ft. and in the lower 15 ft. penciljointing, trending n30E, occurs in the upper 25 ft, the culvert on the north side of the E-W road is 35 ft. above the base. Poorly exposed in the lower 15 ft. The Vilas Shale, including the beds 2, 3, 4, and 5 is 7 ft. thick.
|
85 ft.
|
|
7
|
Limestone - grayish orange (10YR7/4) to dark yellowish-orange (10YR6/6) hard, very thin bedded and irregular bedded; contains many thin clayey interbeds. Fossils are common and include abundant large Heliospongia, Girtyocoelis and crinoid stem fragments., and less abundant Neospirifer Derbyia, Marginifera, Crurithyris, Echinoconchus, horn corals, and fenestrate bryozoans. A coarse calcarenite occurs in the upper foot and a half and includes, among the very abundant crinoid fragments, a few high-spired gastropods and small Osagia; Girtyocoelia and Heliospongia occur in the more finely crystalline parts of the upper foot. Fossils are most abundant near the top and base, the middle protion being mottled light gray and orange with scattered fossils. About a foot above the base is a 3 in. bed of small crinoid fragments and algal bodies (Osagia?) that is essentially a calcarenite. It is followed upward by hard limestone that contains local pockets filled with crinoid fragments of all sizes.
|
8.8 ft.
|
|
8
|
Shale - light gray (N7), light brownish gray (5Y6/1) and light olive gray (5Y5/2), very fossiliferous and calcareous. The calcum carbonate content becomes excessive in two thin zones about 3 and 6 ft. above the base and very fossilifrous shale goes laterally into nodular brownish gray limestone, the fossil content consists predominantly of crinoid stems, Heliospongia and Girtyocoelia. Also included are fragments of cirnoid heads and plates, ramose and fenestrate bryozoans, horncorals, Hustedia, a gastropod much like Trpospira, and other brachiopod fragments that look like parts of Marginifera, Neospirifer, and Composita. The shale is very thin bedded, almost fissile, but does not break into large plates but crumbles. The calcareous zones occur parallel to the beddin and some bedding planes contain many more fossils than others, although the fossil content is distributed throughout. Shale becomes increasingly calcareous near the upper contact.
|
8.2 ft.
|
|
9
|
Limestone - grayish orange (10YR7/4) to dark yellowish orange (10YR6/6) hard, very fossiliferous, weathers to a knobby surface, and rather platy locally, generally a single thin bed. Fossil content consists mainly of fragments of crinoid stems, fenestrate bryozoans, encrusting bryozoans, and various brachiopod remains including Meekella, Hustedia. Also, two fairly well preserved crinoid calyxes were noted.
|
|
|
