natural gas from shale
Chevron is the first company to earn Center for Sustainable Shale Development certification.
the shale opportunity
In the United States, shale gas has helped trigger an energy renaissance. This clean-burning fuel holds promise for nations around the world seeking to strengthen energy security and generate economic growth. According to the study America’s New Energy Future, by research company IHS, shale gas is contributing to the U.S. economy by creating jobs and driving a rebirth of manufacturing.
Globally, there are more than 7,500 trillion cubic feet of technically recoverable shale gas resources.
Natural gas from shale production has risen 30-fold since 2000, delivering increased energy supplies and reduced energy costs.
The amount of recoverable shale gas available is equivalent to about 60 years of the world's current natural gas demand.
where we operate
Chevron holds 600,000 net acres (2,428 sq km) in the Marcellus Shale, one of North America’s largest and richest sources of natural gas from shale. The Marcellus runs beneath large swaths of Pennsylvania, West Virginia, and eastern Ohio and New York.
The company also holds a significant position in the Utica Shale, which lies partially beneath the Marcellus.
In the Permian region (Texas and New Mexico), Chevron holds 1.5 million net acres (6,070 sq km) in the Delaware and Midland basins, where it is developing tight oil and liquids-rich gas shales.
The company also holds shale and tight resource opportunities elsewhere in the midcontinent region, primarily in East Texas and in the Piceance Basin in northwestern Colorado.
In Alberta, Chevron Canada Limited has a 70 percent operated interest in approximately 228,000 net acres in the liquids-rich Duvernay shale formation. A 16-well appraisal program is under way. At the Horn River and Liard shale basins in British Columbia, the company holds 300,000 net acres (1,214 sq km). These significant resources support the proposed Kitimat liquefied natural gas project.
In Argentina, Chevron produces crude oil and natural gas through its wholly owned subsidiary Chevron Argentina S.R.L. The company’s interests include exploration for and development of shale oil and gas resources from the Vaca Muerta formation, located in Neuquén Province. Chevron Argentina S.R.L. holds an 85 percent-owned and operated interest in one concession, covering 94,000 net acres (380 sq km), that has both conventional production and Vaca Muerta Shale potential. Also in the Vaca Muerta Shale formation, another Chevron subsidiary participates in two areas covering 73,000 net acres (294 sq km): the Loma Campana concession and the Narambuena blocks.
According to the U.S. Energy Information Agency, Argentina holds the world’s second-largest shale gas reserves. Vaca Muerta is Argentina’s largest shale gas play, with an estimated 308 trillion cubic feet of dry, wet and associated shale gas resources.
how we operate
signing leases and securing permits
Before exploration begins, Chevron works with governments, local authorities and landowners to obtain licenses and permissions. We conduct environmental, social and health studies to identify potential impacts of our operations. This includes assessing and planning the location of well pads, access roads and facilities to reduce potential impacts on the environment. Studies, assessments and the securing of permits may continue throughout the life of the well.
gathering seismic data
Seismic imaging is a tool that helps us understand what lies beneath the earth’s surface by bouncing sound waves off underground rock structures to build a picture of the subsurface rock formations and determine if they contain oil or gas. Seismologists use seismic trucks to generate sound waves and ultrasensitive devices called geophones to record how the sound waves echo within the earth. By studying the echoes, earth scientists try to determine the best location to place the well in the shale rock. Seismic imaging also helps well-site teams optimize drilling before it starts. Seismic data collection requires permits by regulators. It can take between six months and one year to study the data.
constructing the well site
Once we have identified which locations might contain natural gas and permits are secured, we build a well site. These sites, called well pads, vary in size, and we work to build pads as small as possible. By drilling multiple wells from one well pad, we minimize land use and the number of roads needed to the site.
drilling the well
With the well site complete, a drilling rig is erected. A well is drilled, usually vertically, until it reaches the target rock. This can be as deep as 3 miles (4.8 km) below the surface. Depending on the shale play basin and the well objective (e.g., appraisal vs. development), a decision will be made whether to complete the vertical target section (e.g., by fracturing stimulation) or to continue drilling as a horizontal well, in which case the rig then drills horizontally 2,000 to 6,000 feet (610 to 1,829 m) outward into the layer of shale rock. Wells are lined with multiple layers of steel casing and cement to prevent gas or fluids, including oil, from entering the shallow groundwater or soil. If the drilling results are not encouraging, the hole is plugged and the site is restored. If we find clear evidence of substantial natural gas, we may continue drilling and plan for testing.
Hydraulic fracturing is a common practice in oil and natural gas development—90 percent of oil and gas wells in the United States undergo fracturing to stimulate production. It has been used since the 1940s in more than 1 million wells in the United States and more than 2 million wells globally. In hydraulic fracturing, a fluid composed of more than 99 percent water and sand and less than 1 percent chemical additives is pumped down the well at a high pressure for a short period of time, usually only hours. This creates a network of cracks in the rock that allows trapped natural gas to flow to the well. The sand helps keep the fractures open and gas flowing. In Chevron’s Marcellus operations, hydraulic fracturing is performed in sections along the length of the horizontal well. The entire process takes five to seven days.
building natural gas pipelines
Once a well has been completed, it is ready to produce natural gas for market. A pipeline is installed from the new well to an existing pipeline system that will take the natural gas to market, where it will be used for electrical generation, heat for homes and chemical feedstock.
remediating the drilling site
It takes up to a year to build the well site and drill and complete the well. After the process is complete, we work with the landowner to restore the land with minimal impact to its original contours. We plant indigenous grass using a process called hydro-seeding to accelerate regrowth. Throughout the well development process, regulatory agencies ensure compliance through regular inspections.
producing natural gas for decades
After the well site has been remediated, the remaining footprint includes a wellhead, a gas processing unit, and one or two water tanks. Natural gas wells that produce from shale rock are expected to have a long production life, spanning several decades. A valuable source of energy for homes and businesses, vehicles, power generation, and other industrial processes, natural gas production brings social as well as economic benefits.
Wells that stop producing and exploration wells that are of no further use are plugged with cement and the equipment is removed. Reclamation takes place during the final months of each well and up to a year beyond. At the end of a well's 40- to 50-year life, the site is fully restored.
Technology is essential to identifying, developing and producing shale reservoirs. We have a technology unit focused exclusively on solving the technical challenges of shale and tight rock formations.
addressing the issues
We take steps to protect groundwater during hydraulic fracturing and over the life of the well. Our wells have multiple layers of steel casing and cement, which form a continuous barrier between the well and the surrounding formations. We perform pressure tests to ensure the well’s integrity. We also conduct a combination of tests over the life of the well to verify long-term integrity. Our wells are designed to protect groundwater for the life of the well. Because fracturing is done thousands of feet beneath the groundwater aquifer, the potential for cracks to leak gas or fracturing fluids into groundwater is extremely low. For example, micro-seismic surveys of shale gas wells in the eastern United States show that fractures are separated from groundwater by more than a mile of rock—a distance as deep as the Grand Canyon.
We are committed to safely and responsibly managing fracturing fluids, flowback and produced water. After the hydraulic fracturing process is complete and the well begins to produce natural gas, a portion of the water used during the fracturing process flows back to the surface. This water is stored temporarily in lined pits or steel tanks until it is either reused in future fracturing jobs or injected into disposal wells permitted and regulated for that purpose. Our well sites are designed to protect the land surface and we restore the land to its original contours after drilling.
We are committed to protecting air quality by reducing emissions from our natural gas operations. We design, construct and operate our wells to reduce emissions; we verify integrity of wells and production equipment; and we participate in voluntary programs to minimize our emissions.
Chevron and the industry have worked for years with governments and other stakeholders to develop programs that encourage the industry to reduce natural gas leaks and improve operational efficiencies.
We support giving the public access to information related to chemicals used in hydraulic fracturing. Water and sand constitute more than 99 percent of fracturing fluid. The remaining 1 percent consists of a small number of chemicals added to improve the efficiency and effectiveness of fracturing. Many of these same substances can also be found in food and beverages.
For more information on chemical disclosure, visit FracFocus.org . This online registry of chemicals used in hydraulic fracturing is a joint project of the Ground Water Protection Council and the Interstate Oil and Gas Compact Commission.
Public confidence in our operations is essential to our success. Transparency and engagement are the key components to maintaining and strengthening that confidence. We seek to engage with the communities where we live and operate. By doing so, we can maximize the contributions we make, learn about local concerns, share information and minimize the possible negative impacts of our activities.
Induced seismicity has long been a very low, but recognized risk of underground fluid disposal wells. Underground disposal wells are one of the ways that the oil and gas industry uses to dispose of produced water, the water that comes up the well with oil and natural gas. There are more than 151,000 U.S. federally-permitted Underground Injection Control (UIC) Class II wells related to oil and gas injection. To date, fewer than 40 of those wells (or < 0.03 percent) have been potentially linked to seismic events felt at the surface, according to data compiled by the U.S. Environmental Protection Agency. When properly planned, operated, and monitored, fluid disposal wells are safe, as demonstrated by decades of disposal operations involving many industries.
The possibility of hydraulic fracturing causing induced seismic events felt at the earth’s surface is even more remote. Energy from the process is almost never sufficiently large enough to cause such an occurrence, according to reports by the U.S. Geological Survey, National Academy of Sciences and the American Association of Petroleum Geologists. Experts at these organizations concluded that any micro-seismic events from hydraulic fracturing are generally too small to present any safety concerns.
Chevron is one of the largest leaseholders in the Marcellus Shale, with 600,000 net acres of leases. Where appropriate, we closely monitor seismicity using acoustic sensors and other proven technologies, such as tracers, to validate our design parameters.
chevron in the marcellus
Chevron is one of the largest leaseholders in the Marcellus Shale, with 600,000 net acres of leases. One of North America’s largest and richest sources of natural gas from shale, the Marcellus runs beneath large swaths of New York, Pennsylvania, West Virginia and eastern Ohio and dips into neighboring states.
investing in the marcellus
Our work in the Marcellus Shale is fueling job growth and strengthening local economies.