How is hydraulic fracturing related to earthquakes and tremors?
Reports of hydraulic fracturing causing felt earthquakes are extremely rare. However, wastewater produced by wells that were hydraulic fractured can cause “induced” earthquakes when it is injected into deep wastewater wells.
Wastewater disposal wells operate for longer durations and inject much more fluid than the hydraulic fracturing operations. Wastewater injection can raise pressure levels in the rock formation over much longer periods of time and over larger areas than hydraulic fracturing does. Hence, wastewater injection is much more likely to induce earthquakes than hydraulic fracturing.
Most wastewater injection wells are not associated with felt earthquakes. A combination of many factors is necessary for injection to induce felt earthquakes.
Why have some estimates of undiscovered technically recoverable oil or gas changed so much from previous estimates?
Petroleum geologists have long known that oil and gas resources were present in “tight” or impermeable formations such as shale. But there was no way feasible way to extract that oil and gas, so they were not “technically recoverable” and were not be included in USGS assessment results.
Thanks to new technologies,...Read Full Answer
Hydraulic fracturing is used in many established oil and gas producing regions of the country as well as some areas new to the petroleum industry. Maps of major shale gas, tight gas, and tight oil basins are available from the U.S. Energy Information Administration, although not all...Read Full Answer
Who is responsible for monitoring the issues associated with hydraulic fracturing and protecting our environment?
Individual states regulate many aspects of oil and gas exploration and production.
Federal land managers, such as the Bureau of Land Management (BLM), the U.S. Forest Service (USFS), and the U.S. Fish and Wildlife Service (USFWS) have some oversight of oil and gas activities on the lands they manage. This includes...Read Full Answer
Hydraulic fracturing in vertical wells has been used for over fifty years to improve the flow of oil and gas from conventional reservoirs. However, the current practice of horizontal drilling coupled with multiple applications of hydraulic fracturing in a single well was pioneered in the late 1980’s and has continued to...Read Full Answer
Hydraulic fracturing, informally referred to as “fracking,” is an oil and gas well development process that typically involves injecting water, sand, and chemicals under high pressure into a bedrock formation via the well. This process is intended to create new fractures in the rock as well as increase the size, extent, and...Read Full Answer
There isn’t really a “typical” fractured well because the amount of water used depends on the rock formation, the operator, whether the well is vertical or horizontal, and the number of portions (or stages) of the well that are fractured. In addition, some water is recycled from fluids produced by the well, so the net...Read Full Answer
The actual practice of hydraulic fracturing (or “fracking”) is only a small part of the overall process of drilling, completing, and producing an oil and gas well.
Environmental issues that are specifically related to hydraulic fracturing include:
- water availability
- spills of chemicals at the
An area undergoing production of oil or gas using hydraulic fracturing technology shares many features with areas where conventional oil or gas is being developed, including:
- Compressor stations
- Processing facilities.
Features that are unique to areas in...Read Full Answer
In a conventional oil or gas field, where the oil or gas is in relatively porous and permeable rock (i.e. the pores are connected), the oil or gas can usually flow naturally from the reservoir rock to the wellbore. Nonetheless, a variety of techniques are often used to improve the flow of oil or gas, including hydraulic...Read Full Answer
Conducted properly, hydraulic fracturing (or “fracking”) has little possibility of contaminating water supplies. Properly constructed wells prevent drilling fluids, hydraulic fracturing fluids, deep saline formation waters, or oil and gas from entering aquifers. Carefully constructed and operated well sites have the ability...Read Full Answer
Most of the water and additives used in hydraulic fracturing (or “fracking”) remain deep underground in the geologic formation from which the oil or gas is being extracted. But some of the fluid, mixed with water or brine from the formation, returns through the well to the surface and is referred to as “produced water”....Read Full Answer
Distant wastewater disposal wells likely induced the third largest earthquake in recent Oklahoma record, the Feb. 13, 2016, magnitude 5.1 event roughly 32 kilometers northwest of Fairview, Oklahoma. These findings from the U.S. Geological Survey are available in the online edition of Geophysical Research Letters.
The occurrence or frequency of earthquakes for which the origin is attributable to human activities.
For the first time, new USGS maps identify the potential for ground shaking from both human-induced and natural earthquakes in 2016.
The rate of earthquakes has increased sharply since 2009 in the central and eastern United States, with growing evidence confirming that these earthquakes are primarily caused by human activity, namely the injection of wastewater in deep disposal wells.
MENLO PARK, Calif.— A paper published today in Science provides a case for increasing transparency and data collection to enable strategies for mitigating the effects of human-induced earthquakes caused by wastewater injection associated with oil and gas production in the United States.
In a new study involving researchers at the U.S. Geological Survey, scientists observed that a human-induced magnitude 5.0 earthquake near Prague, Oklahoma in November 2011 may have triggered the larger M5.7 earthquake less than a day later.
USGS map displaying potential to experience damage from a natural or human-induced earthquake in 2017. Chances range from less than one percent to 12 percent.
USGS map displaying potential to experience damage from a natural or human-induced earthquake in 2016. Chances range from less than one percent to 12 percent.
USGS map displaying 21 areas where scientists have observed rapid changes in seismicity that have been associated with wastewater injection. The map also shows earthquakes—both natural and induced—recorded from 1980 to 2015 in the central and eastern U.S. with a magnitude greater than or equal to 2.5.
Hydraulic fracturing is the process of injecting wells with water, sand, and chemicals at very high pressure. This process creates fractures in deeply buried rocks to allow for the extraction of oil and natural gas as well as geothermal energy. USGS scientists discuss the opportunities and impact associated with hydraulic fracturing. Doug Duncan, associate coordinator for the USGS Energy Resources Program, addresses the increasing role that unconventional oil and gas resources play in the nation's petroleum endowment. USGS hydrologist Dennis Risser discusses some of the major water availability and quality challenges associated with natural gas development, with a focus on the Marcellus Shale in Pennsylvania. Bill Leith, associate coordinator the USGS Hazards Program, concludes by discussing the potential connection between disposal of waste fluids from hydraulic fracturing and earthquakes.
Research has identified 17 areas in the central and eastern United States with increased rates of induced seismicity. Since 2000, several of these areas have experienced high levels of seismicity, with substantial increases since 2009 that continue today.
Bryant Platt digs a hole to install seismometers at a home in southern Kansas. Seismometers are in the foreground.
Most wastewater currently disposed of across the nation is generated and produced in the process of oil and gas extraction. Saltwater is produced as a byproduct during the extraction process. This wastewater is found at nearly every oil and gas extraction well.
The other main constituent of wastewater is leftover hydraulic fracturing fluid. Once hydraulic fracturing is completed, drilling engineers extract the fluids that are remaining in the well. Some of this recovered hydraulic fracturing fluid is used in subsequent fracking operations, while some of it is disposed of in deep wells.