Written by Lisa Mahr.
Fracking has become an industry standard in the oil development industry. If you drive through the states of Pennsylvania, Texas, North Dakota, Arkansas, Montana, and California you will see lots of activity involving fracking. What is fracking and what materials are used in this process?
Hydraulic fracturing, or otherwise known as “fracking”, is used to produce petroleum fluids, such as oil, natural gas, and natural gas liquids from rock units that lack adequate pore space for these fluids to flow into a well. Many Shale units throughout the United States harbor natural gas liquids. In many of these units hydraulic fracturing is required to release the liquids. Examples of these units include the Marcellus Shale in Pennsylvania, Bakken Formation in Montana and North Dakota, Hayensville Shale in Arkansas, Eagle Ford Shale in Texas, and the Monterey Shale in California. All units hold promise for expanded production of petroleum products.
The hydraulic fracturing process generates fractures in the rock. This is accomplished by drilling a well into the rock, sealing the portion of the well in the petroleum-bearing zone, and pumping water under high pressure into that portion of the well. This water is generally treated with chemicals and thickeners such as guar gum to create a viscous gel. This gel is used to help carry sand down into the fractures where the mixture (proppant) is used keep the fissures open.
“Hydraulic Fracturing Diagram” Courtesy of First Electric Newspaper (2012).
Large pumps at the Earth’s surface increase the water pressure in the sealed portion of the well until it is high enough to exceed the breaking point of the surrounding rocks. Once the rocks breaking point is reached it will fracture suddenly and water will rush into the fractures, inflating them and extending them deeper into the rock. Billions of sand grains are carried deep into the fractures by this sudden rush of water. A few thousand tons of sand can be required to stimulate a single well.
Frac sand is composed of high purity (90%) silica that has spherical shape enabling it to be carried by the gel used in hydraulic fracturing with minimal turbidity. Frac sand must have uniform grain size, must be highly durable, and the particles cannot have been damaged by tectonics. Most frac sand
is between 0.4 – 0.8 mm (Passing No. 20 – No. 40 Sieve) and is usually found in sandstone formations that have been through several cycles of weathering and erosion. These cycles have filtered out all other minerals and have produced a rounded shape to the sand particles. Sand that has been dredged from rivers, excavated from terraces, removed from beaches, or taken from areas with tectonic activity has proven to not meet the requirements and typically cannot withstand the pressures required to be a suitable proppant.
Due to strict requirements on the overall quality of frac sand, the main sources have been found in Wisconsin, Texas, Illinois, Indiana, Iowa, Kansas, Kentucky, Minnesota, Michigan, Missouri, and Nebraska.
“USGS Hydraulic Fracturing Sand” by Bill Cunningham, USGS, public domain – http://gallery.usgs.gov/photos/03_08_2013_v0Qd72Gts4_03_08_2013_2. Licensed under Public domain via Wikimedia Commons.
Synthetic frac sand is available and is made from sintered bauxite or small metal beads made from aluminum. However, synthetic frac sand is extremely expensive. According to the U.S. Geological Survey Minerals Yearbook for 2011, the average price for frac sand in the U.S. was about $55 per ton. This compares favorably with the average price for sintered bauxite of $300 per ton.
Fracking in California has become a hot topic lately with California’s fracking bill SB 4 released in 2013. Some of SB 4 requirements include:
- The state’s Department of Natural Resources will need to conduct an independent, peer-reviewed scientific assessment of fracking by January 2015 on any land where fracking is to occur. This assessment must cover effects on groundwater, wildlife and native vegetation, public health, worker safety, and air quality.
- Companies with an active interest in fracking in California must apply for a permit with the state’s Division of Oil, Gas and Geothermal Resources (DOGGR) beginning January 2014. Permits are valid for a year. In order to obtain a permit, applicants are required to provide detailed information including the location, chemicals used, length of time, and management plans for the site.
- Fracking and related practices will be allowed to continue in California, while the state conducts its scientific assessment and decides on suitable regulations.
- Fracking permits obtained must be provided to owners of any property within 500 yards of a well head 30 days before operations begin. This will allow the property owner’s the ability to request water sampling and testing by a third-party contractor to be completed prior to operations commencement at the operator’s expense.
Fracking has been occurring in California for over 50 years according to the Bureau of Land Management (BLM). Fracking has occurred offshore, on BLM land, and on private lands throughout oil rich areas of California. New regulations fostered by SB 4 require companies to more closely monitor their activities and the effects they have on the environment.
Currently, most fracking in California has occurred in Kern County. However, since discovering that the Monterey Shale, in the Central Valley, might contain more than 15 billion barrels of frackable oil, the practice is expected to boom. The BLM will resume leasing on public land in California next year for the use of fracking and other related activities. According to the BLM, 82% of the approximate 17,000 acres of mineral rights that will be leased for fracking lie under private land. In many cases land owners are finding that they only own the surface of their property and oil companies are leasing the rights to the oil that lies beneath them. In this case land owners work up an agreement with the interested parties to protect their rights and their land.
With this rise in interest in fracking in California, frac sand will become a highly valuable commodity. According to Fractracker.org and the Office of Mine Reclamation, there are currently only two active frac sand producers operating in California. These mining operations are located in San Juan Capistrano, and Ione. There is a high likely hood that other areas in California have the potential for frac sand development. Some of these areas are likely to be near the current operations, along the western edge of the Sierra’s and possibly in the LA Basin.
As fracking activity increases in California, the market for frac sand in California will increase. The “Sand Rush” is on – don’t miss it.
Lisa Mahr is a former employee of EnviroMINE, Inc.