A new mineral rush is underway in the upper Midwest of the United States, especially in Wisconsin and Minnesota, for deposits of high-quality frac sand that the mining industry calls “Northern White” sand or “Ottawa” sand. Frac sand is a specialized type of sand that is added to fracking fluids that are injected into unconventional oil and gas wells during hydraulic fracturing (fracking or hydrofracking), a process that enhances petroleum extraction from tight (low permeability) reservoirs. Frac sand consists of natural sand grains with strict mineralogical and textural specifications that act as a proppant (keeping induced fractures open), extending the time of release and the flow rate of hydrocarbons from fractured rock surfaces in contact with the wellbore.
The current sand mining surge has been driven by the boom in unconventional oil and gas production that has been largely spurred by advancements in technology promoting the expansion of hydraulic fracturing and horizontal drilling over the past decade. Because of its superior quality, the sand of the upper Midwest not only supports the majority of domestic oil and gas production, but it also supplies frac sand to some of Canada’s western shale basins.