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The AAPG/Datapages Combined Publications Database

AAPG Bulletin

Abstract


Volume: 67 (1983)

Issue: 9. (September)

First Page: 1456

Last Page: 1457

Title: Aux Vases-Renault-Yankeetown Depositional Sequence in Comparison to Other Chesterian Depositional Sequences: ABSTRACT

Author(s): James R. Jennings, George H. Fraunfelter

Article Type: Meeting abstract

Abstract:

The major Chesterian sandstone units from the Bethel to the Degonia have a thick, lower progradational part. This is typically overlain by a sequence of thin-bedded sandstone, siltstone, and shale-bearing thin, insitu coals and rooted zones wherever the underlying sandstone is thick. Overlying these coals and rooted zones is a much thinner transgressive

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sequence usually including thin, marine sandstones which form a transition into the overlying limestones. Many of these limestones display remarkable lateral continuity. In the outcrop area of southeastern Missouri and southwestern Illinois, the Aux Vases, Renault, and Yankeetown Formations are primarily clastic units which interfinger with one another and probably make up a single depositional package. The massive sandstones, called the Aux Vases, occur at different horizons within the sequence and interfinger with shales which have been variously assigned to either the Renault or the Aux Vases. Furthermore, the Aux Vases differs from other Chesterian sandstone units in that it does not contain coal beds anywhere, and it displays prominent herringbone-type cross-beds. In some places, the sandstone contains marine fossils. However, the Renault, which is usually considered to be a limestone unit, in many places does not contain limestone, and when marine limestone lenses are present they are highly discontinuous. The Yankeetown is a thin, highly continuous unit that typically contains characteristic cherty sandstones along with sandstones like those found in other Chesterian sandstone units, as well as shales and limestones. Some of these strata also contain marine fossils. Thus, the Aux Vases differs from other major Chesterian sandstone units in showing strong tidal influence and in lacking both coals and rooted zones, but is similar to other Chesterian sands in showing widespread marine influence.

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