As part of the hydraulic fracturing process, proppants (commonly natural sands and manufactured ceramic spheres) are used to keep the fractures that are created open for the enhanced flow of oil and gas from the fractures into the wellbore.
The continued success of the Bakken/Three Forks oil play in North Dakota, through the hydraulic fracturing of oil and gas wells and placement of proppants in fractures during the stimulation of completed wells, has created an unprecedented demand for natural proppants in the Williston Basin.
Recently, the oil and gas industry has relaxed proppant testing specifications in parts of the U.S. in favor of more regional or local proppant sand source utilization. The high prices associated with transporting high-quality proppants from their source areas in the upper Midwest have also resulted in an evolving trend in other U.S. shale basins to develop more cost-effective, local sand resources. This is why NDGS geologists continue to evaluate North Dakota’s eolian and bedrock sandstone resources as potential alternatives to the much pricier out-of-state proppant sands.
Samples are evaluated for proppant suitability in accordance with testing standards and specifications published by the American Petroleum Institute (API): API STD-19C (API, 2018) and the International Organization for Standardization (ISO): ISO 13503-2 (ISO, 2006). Testing includes: gross sample inspection and field description (including field acid reactivity), sample washing and comparison, stereo microscope photomicrography, particle shape factors (roundness and sphericity) analysis, qualitative and quantitative mineralogy via X-ray diffraction (XRD), crush resistance, acid solubility, turbidity, loss on ignition, and sand density testing. Tests were again performed on the most abundant size classes, as determined by sieve analysis, which typically fell into the 40/140 and 70/140 size classes. Over the past decade, desired sand specifications have changed with continued refinements in the hydraulic fracturing process. Sand in the coarser size classes (e.g., 30/50) was originally preferred, which over time has changed to the finer sand size classes in the 40/70 and 70/140 ranges which generally demonstrate much higher crush resistance than coarser fractions. Also broadening the testing size class range, such as in a 40/140 or 50/140 cut continues to result in higher crush resistance values in some samples and provides useful data over a larger amount of the deposit.
REPORTS OF INVESTIGATION
| RI-132 | Sandstones Of The Fox Hills and Hell Creek Formations In North Dakota: Proppant Testing and Characterization by Anderson, F.J., and Moxness, L.D., 2022. |
| RI-127 | Evaluation of Windblown Sand Deposits in Eastern North Dakota for Potential Use as Proppant by Anderson, F.J., 2021. |
| RI-126 | Evaluation of Windblown Sand Deposits in South-Central North Dakota for Potential Use as Proppant by Anderson, F.J., 2020. |
| RI-124 | Evaluation of Windblown Sand Deposits in North-Central North Dakota for Potential as Proppant by Anderson, F.J., 2020. |
| RI-123 | Evaluation of Eolian Sand Deposits in North and South-Central North Dakota for Potential Use as Proppant by Anderson, F.J., 2019. |
| RI-121 | Evaluation of Tertiary (Paleocene) Bedrock Sandstone of the Sentinel Butte and Bullion Creek Formations for Potential Use as Proppant by Anderson, F.J., Moxness, L.D., Kruger, N.W., Murphy, E.C., and Maike, C.A., 2019. |
| RI-110 | Investigation of Sand Resources in North Dakota: Sedimentological Characterization of Surficial Sand Deposits for Potential Use as Proppant by Anderson, F.J., 2011. |
