Numerous peer-reviewed studies and official geological surveys document that hydraulic fracturing operations can trigger or induce earthquakes by increasing fluid pressure and reactivating preexisting faults.
Abstract We compile published examples of induced earthquakes that have occurred since 1929 that have magnitudes equal to or greater than 1.0. Of the 198 possible examples, magnitudes range up to 7.9. The potential causes and magnitudes are (a) mining (M 1.6–5.6); (b) oil and gas field depletion (M 1.0–7.3); (c) water injection for secondary oil recovery (M 1.9–5.1); (d) reservoir impoundment (M 2.0–7.9); (e) waste disposal (M 2.0–5.3); (f) academic research boreholes investigating induced seismicity and stress (M 2.8–3.1); (g) solution mining (M 1.0–5.2); (h) geothermal operations (M 1.0–4.6) and (i) hydraulic fracturing for recovery of gas and oil from low-permeability sedimentary rocks (M 1.0–3.8). Reactivation of faults and resultant seismicity occurs due to a reduction in effective stress on fault planes. Hydraulic fracturing operations can trigger seismicity because it can cause an increase in the fluid pressure in a fault zone. Based upon the research compiled here we propose that this could occur by three mechanisms. Firstly, fracturing fluid or displaced pore fluid could enter the fault. Secondly, there may be direct connection with the hydraulic fractures and a fluid pressure pulse could be transmitted to the fault. Lastly, due to poroelastic properties of rock, deformation or ‘inflation’ due to hydraulic fracturing could increase fluid pressure in the fault or in fractures connected to the fault. The following pathways for fluid or a fluid pressure pulse are proposed: (a) directly from the wellbore; (b) through new, stimulated hydraulic fractures; (c) through pre-existing fractures and minor faults; or (d) through the pore network of permeable beds or along bedding planes. The reactivated fault could be intersected by the wellbore or it could be 10s to 100s of metres from it. We propose these mechanisms have been responsible for the three known examples of felt seismicity that are probably induced by hydraulic fracturing. These are in the USA, Canada and the UK. The largest such earthquake was M 3.8 and was in the Horn River Basin, Canada. To date, hydraulic fracturing has been a relatively benign mechanism compared to other anthropogenic triggers, probably because of the low volumes of fluid and short pumping times used in hydraulic fracturing operations. These data and analysis should help provide useful context and inform the current debate surrounding hydraulic fracturing technology.
In the southern Sichuan Basin, China, the recent increase in the seismic activity has been suspected to be related to hydraulic fracturing stimulation for producing the shale gas. In this study, we used the monitoring data from a local seismic network within the shale gas blocks to study the earthquakes near the shale gas production wells that have detailed injection data. Comparison of the timing of earthquakes and stimulation schedule of the studied well pads indicates an apparent correlation between the seismic activity and hydraulic fracturing. The results of seismic velocity tomography reveal that the reactivation of preexisting faults due to fluid diffusion is the primary cause of the observed earthquakes. Focal mechanism analysis combined with geomechanical modeling indicates that the increased pore pressures resulted from hydraulic fracturing are sufficient to trigger seismic slip on the faults.
China's shale gas production has grown annually by 21% since 2017 with long-term national energy strategy calling for continued expansion. This large-scale shale gas development is challenged by constraints on water supply. It requires over 6,000 new wells to be drilled within the Yangtze River Basin in South China-one of China's most populated regions with sensitive ecological and geological conditions, posing significant environmental threats to the hydrosphere, atmosphere, and biosphere. Hydraulic fracturing-induced seismicity also adds to the existing earthquake risk for the Sichuan/Chongqing region. These potential negative impacts challenge both China's and the United Nations' sustainable development goals. We explore China's current shale gas operations in the Yangtze River Basin and their interaction with the environment from these multiple perspectives. We then suggest future improvements to practice that will promote sustainable development to jointly satisfy China's burgeoning energy needs. We conclude that China's shale gas industry would benefit from an innovation ecosystem that involves companies and research institutions, and that there is an urgent need to implement environmental regulations for shale gas extraction.
Triggered quakes get unconventional The big earthquakes induced by human activity are mostly linked with disposal of wastewater. However, Bao and Eaton implicate hydraulic fracturing (or fracking) as the culprit in western Canada (see the Perspective by Elsworth). Fracking near Fox Creek, Alberta, reactivated faults, clustering earthquakes along the old fault traces. Fracking does not appear to cause large earthquakes in many other areas that are prone to induced seismicity. Understanding the underlying causes of seismicity in different localities is vital for developing sound regulation to limit damaging earthquakes. Science , this issue p. 1406 ; see also p. 1380
Induced Seismicity The big earthquakes induced by human activity are mostly linked with disposal of wastewater. However, Bao and Eaton implicate hydraulic fracturing (or fracking) as the culprit in western Canada (see the Perspective by Elsworth). Fracking near Fox Creek, Alberta, reactivated faults, clustering earthquakes along the old fault traces. Fracking does not appear to cause large earthquakes in many other areas that are prone to induced seismicity. Understanding the underlying causes of seismicity in different localities is vital for developing sound regulation to limit damaging earthquakes. Science , this issue p. [1406][1]; see also p. [1380][2] [1]: /lookup/doi/10.1126/science.aag2583 [2]: /lookup/doi/10.1126/science.aal2584
(also known as hydraulic fracturing, fracing, hydrofracturing, or hydrofracking) is a well stimulation technique involving the fracturing of formations
Fracking (also known as hydraulic fracturing, fracing, hydrofracturing, or hydrofracking) is a well stimulation technique involving the fracturing of formations in bedrock by a pressurized liquid. The process involves the high-pressure injection of "fracking fluid" (primarily water, containing sand or other proppants suspended with the aid of thickening agents) into a wellbore to create cracks in
The potential environmental effects of hydraulic fracturing include air pollution, contributions to climate change, high water consumption, groundwater contamination, land use, induced earthquakes, noise pollution, and various health effects on humans. Research is underway to determine if human health has been affected by air and water pollution, and rigorous following of safety procedures and regulation is required to avoid harm and to manage the risk of accidents that could cause harm.
SUMMARY Shale gas extraction could produce underground stress perturbation and local seismicity, which could put a threat human casualty. The Weiyuan area in the Sichuan province, China, underwent massive gas production and a significant increase of earthquake since 2015. In this study, we focus on human-induced subsurface hydrofracturing, calculate cumulative underground Coulomb-stress changes using a 3-D numerical model and probe the main cause of recent seismic activity in the Weiyuan area based on continuous regional stress/displacement loading. The simulation reveals the regional extent of positive Coulomb stress change with fractures matches the distribution of the moderate and microseismicity in the past ten years. Background regional tectonic stress in the vicinity of the active fault likely resulted in earthquake preparation within and around the active faults; hydraulic fracturing changes mainly the displacement and stress pattern in the vicinity of the fracturing wells, and enhanced fracturing intensity [fracture volume-to-model volume ratio (θ)], causes more obvious difference; faults may be locked prior to fracturing and even small fracturing intensity may trigger the earthquakes near faults and fracturing wells; the seismic risk will be significantly increased near the two faults and fracturing wells in the next 50 yr.
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May 31, 2018
PubTalk 5/2018 — Yes Humans really are causing induced earthquakes
PubTalk 5/2018 — Yes Humans really are causing induced earthquakes
PubTalk 5/2018 — Yes Humans really are causing induced earthquakes
PubTalk 5/2018 — Yes Humans really are causing induced earthquakes
Title: Yes, Humans Really Are Causing Earthquakes! How Energy Industry Practices are Causing Earthquakes in America's Heartland
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Communications and Publishing , Public Lecture Series
video thumbnail: Science or Soundbite? Shale Gas, Hydraulic Fracturing, and Induced Earthquakes
Science or Soundbite? Shale Gas, Hydraulic Fracturing, and Induced Earthquakes
April 3, 2012
Science or Soundbite? Shale Gas, Hydraulic Fracturing, and Induced Earthquakes
Science or Soundbite? Shale Gas, Hydraulic Fracturing, and Induced Earthquakes
Science or Soundbite? Shale Gas, Hydraulic Fracturing, and Induced Earthquakes
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.
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Natural Hazards
April 3, 2012
Science or Soundbite? Shale Gas, Hydraulic Fracturing, and Induced Earthquakes
Science or Soundbite? Shale Gas, Hydraulic Fracturing, and Induced Earthquakes
Science or Soundbite? Shale Gas, Hydraulic Fracturing, and Induced Earthquakes
Science or Soundbite? Shale Gas, Hydraulic Fracturing, and Induced Earthquakes
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.
By
Natural Hazards
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March 19, 2019
Delayed dynamic trigg