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Measured sections and correlations of mid-Cretaceous rocks near the Lombard thrust of the Helena Salient in southwestern Montana

January 1, 1995

Two surface sections that generally characterize mid-Cretaceous strata in the central to southern part of the Helena salient of the Montana thrust belt (Figs. 1 and 2) are presented here. We have not published detailed descriptions of the lithic units of these sections, and the stratigraphic correlations are tentative. The sections are presented in this preliminary form because they may aid interpretations of seismic and borehole data of petroleum exploration companies active in the salient.

Publication Year 1995
Title Measured sections and correlations of mid-Cretaceous rocks near the Lombard thrust of the Helena Salient in southwestern Montana
DOI 10.3133/ofr95841
Authors T. S. Dyman, R. G. Tysdal, K.W. Porter, G. A. Thompson
Publication Type Report
Publication Subtype USGS Numbered Series
Series Title Open-File Report
Series Number 95-841
Index ID ofr95841
Record Source USGS Publications Warehouse