| Abstrakt: |
Sandstones in the Fort Union Group (Paleocene) were sampled in western and central North Dakota, along the Little Missouri River Valley in northwestern Billings, southern McKenzie, and northwestern Slope counties, and from surface coal mines near Underwood and Beulah, North Dakota, during the fall of 2018. During the following winter, some of these sandstones were evaluated for use as proppant sand in the hydraulic fracturing of oil and gas wells in the Williston Basin. Sandstone characterization testing was performed on 11 samples from six locations revealing that these sandstones are dominantly well-;sorted, fine-;grained (70/140), sands containing quartz contents ranging from 41 to 63%, with crush resistance K-;values of 3,000 psi or less. Acid solubilities in these sandstones ranged from 6.5 to 22.2% with turbidity values ranging from 29 to 220 FTU. Loss on ignition testing, as a proxy for detrital lignite content, ranged from 2.44 to 9.62%. Sand grain roundness and sphericity averaged 0.5 and 0.6, respectively. Average bulk density of these sandstones is 77.2 pcf. Albite contents averaged 26% within a single 56-;foot thick outcrop of channel sandstone of the Sentinel Butte Formation in northwestern Billings county. [ABSTRACT FROM AUTHOR] |
