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USGS · 70232798

Revision of Mississippian stratigraphy, eastern Idaho and northeastern Utah

William Jasper Sando·J. Thomas Dutro·Charles Sandberg·Bernard L. Mamet
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Abstract

New paleontologic evidence requires a revision of previous interpretations of the stratigraphy of Mississippian sequences in the Cordilleran miogeosyncline of eastern Idaho and northeastern Utah. A postulated unconformity between rocks of early Osagean age and rocks of middle Meramecian age is no longer tenable in the light of new data. The new evidence supports continuous deposition from the Lodgepole Limestone (Kinderhookian and early Osagean age) into the Little Flat Formation (early Osagean to middle Meramecian age) and its equivalents, and the interpretation of a phosphatic siltstone and shale interval in the lower part of the Little Flat Formation as a starved-basin facies.

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Journal of Research of the U.S. Geological SurveyArticle
90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 39.90973623453719° to 45.72152152227954° latitude; -114.08203125° to -109.0283203125° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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William Jasper Sando, J. Thomas Dutro, Charles Sandberg, Bernard L. Mamet. 1976. Revision of Mississippian stratigraphy, eastern Idaho and northeastern Utah. https://pubs.usgs.gov/publication/70232798

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