Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Geology

Theses and Dissertations

2004

Stratigraphic--Ordovician; Sedimentation and deposition--North Dakota; Sedimentation and deposition--Montana

Articles 1 - 1 of 1

Full-Text Articles in Physical Sciences and Mathematics

Discontinuities In The Icebox Formation (Ordovician), Williston Basin, North Dakota And Montana, Aaron J. Ulishney Jan 2004

Discontinuities In The Icebox Formation (Ordovician), Williston Basin, North Dakota And Montana, Aaron J. Ulishney

Theses and Dissertations

The Ordovician Winnipeg Group is composed of three formations; in ascending order, the Black Island Formation, the Icebox Formation, and the Roughlock Formation. The Icebox Formation is largely composed of shale. This work shows that discontinuities and coarser facies exist within the Icebox Formation and that they are traceable throughout the subsurface of North Dakota and eastern Montana. This work also illustrates possible sea-level changes during the deposition of the Icebox Formation along with probable source areas providing detrital sediments into the study area.

Gamma-ray wireline logs were used to distinguish the formations of the Winnipeg Group from each other, …