Upper Cambrian stromatolitic biostrome, Clinetop Member of the Dotsero Formation, western Colorado
In: Geological Society of America Bulletin, Jg. 87 (1976), S. 1331-1331
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Zugriff:
The Clinetop Member of the Dotsero Formation consists of carbonate pebble conglomerate and stromatolitic algal heads as much as 1.5 m thick. Isopach maps indicate that the Clinetop Member occupies an area 24 to 32 km wide and 64 to 80 km long (1,500 to 2,600 km 2 ) and trends approximately N60°W. The member consists of three stratigraphic units composed of 3 to 43 cm of basal carbonate pebble conglomerate, 0 to 91.4 cm of algal heads, and 0 to 2.1 cm of upper bioclastic and carbonate pebble conglomerate. The lower one-half to two-thirds of the algal heads are of the SH-V (cryptozoon) structural type, whereas the upper one-half to one-third are of the LLH-C (collenia) structural type. Channels filled with clastic carbonate as deep as 68 cm cut the algal-head unit. The orientation of the channels averages N46°E. Comparison of the algal heads to modern stromatolitic heads suggests that they formed in the intertidal environment of a tropical to subtropical sea. The SH-V algal structures formed in a high-energy, seaward, intertidal environment, whereas the LLH-C structures formed in a low-energy, landward, intertidal environment. Channels were formed by tidal runoff. A gradual regression of the sea across a stable platform is suggested to explain the distribution of the Clinetop Member.
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Upper Cambrian stromatolitic biostrome, Clinetop Member of the Dotsero Formation, western Colorado
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Autor/in / Beteiligte Person: | Campbell, John A. |
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Zeitschrift: | Geological Society of America Bulletin, Jg. 87 (1976), S. 1331-1331 |
Veröffentlichung: | Geological Society of America, 1976 |
Medientyp: | unknown |
ISSN: | 0016-7606 (print) |
DOI: | 10.1130/0016-7606(1976)87<1331:ucsbcm>2.0.co;2 |
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