Skip to Main Content
Skip Nav Destination
GEOREF RECORD

Evaporite solution breccias from the Mississippian of southwest Montana

Gerard V. Middleton
Evaporite solution breccias from the Mississippian of southwest Montana
Journal of Sedimentary Petrology (June 1961) 31 (2): 189-195

Abstract

Zones of breccia within the Madison group of SW. Montana consist of very poorly sorted angular fragments of calcilutite or silty limestone, which are set in a fine-grained matrix of crushed "rock-flour" and cemented by calcite. In places where the matrix was silty or sandy it weathers yellow-brown and contains abundant authigenic quartz crystals. The breccias are confined stratigraphically to zones which may be correlated with evaporites in subsurface sections. The upper contacts of the breccia zones are indistinct, but the lower contacts are well defined; in some localities, brecciation occurred in place with little displacement of the fragments. The brecciation resulted from the collapse and crushing of nonsoluble strata after the solution by ground water of beds of evaporite.


ISSN: 0022-4472
Coden: JSEPAK
Serial Title: Journal of Sedimentary Petrology
Serial Volume: 31
Serial Issue: 2
Title: Evaporite solution breccias from the Mississippian of southwest Montana
Pages: 189-195
Published: 196106
Text Language: English
Publisher: Society of Economic Paleontologists and Mineralogists, Tulsa, OK, United States
Accession Number: 1961-007223
Categories: Igneous and metamorphic petrology
Document Type: Serial
Bibliographic Level: Analytic
Illustration Description: illus.
N44°30'00" - N49°00'00", W116°01'60" - W104°01'60"
Country of Publication: United States
Secondary Affiliation: GeoRef, Copyright 2017, American Geosciences Institute. Reference includes data from Bibliography and Index of North American Geology, U. S. Geological Survey, Reston, VA, United States
Update Code: 1961
Close Modal

or Create an Account

Close Modal
Close Modal