Geochemistry of water in aquifers and confining units of the Northern Great Plains in parts of Montana, North Dakota, South Dakota, and Wyoming

Abstract

The geochemistry of water in five aquifers and two confining units in the Williston Basin of the Northern Great Plains is similar and is controlled by halite dissolution. In areas outside the Williston Basin ground-water is fresh and controlled by the solution chemistry of carbonate and sulfate minerals.