Induced seismicity
Encyclopedia
Induced seismicity refers to typically minor earthquake
s and tremors that are caused by human
activity that alters the stresses and strains on the Earth's crust
. Most induced seismicity is of an extremely low magnitude
. A few sites regularly have larger quakes, such as The Geysers
geothermal plant, which in the past 5 years has averaged 2 M4 events and 15 M3 events every year.
in the rock
below and through fissures in the rocks, lubricates the fault, which can trigger earthquakes. Reservoir-induced seismic events can be relatively large compared to other forms of induced seismicity. The first case of reservoir induced seismicity occurred in 1932 in Algeria’s Oued Fodda Dam
. Unfortunately, understanding of reservoir induced seismic activity is very limited. However, it has been noted that seismicity appears to occur on dams with heights larger than 100 meters. The extra water pressure created by vast reservoirs is the most accepted explanation for the seismic activity. Induced seismicity is usually overlooked due to cost cutting during the geological surveys of the locations for proposed dams. Once the reservoirs are filled, induced seismicity could occur immediately or with a small time lag.
The 6.3 magnitude 1967 Koynanagar Earthquake
occurred in Maharashtra
, India
with its epicenter, fore and aftershocks all located near or under the Koyna Dam reservoir. 180 people died and 1,500 were left injured. The effects of the earthquake were felt 230 km away in Bombay with tremors and power outages. During the beginnings of the Vajont Dam
in Italy, there were seismic shocks recorded during its initial fill. After a landslide almost filled the reservoir in 1963, causing a massive flooding and around 2,000 deaths, it was drained and consequently seismic activity was almost non-existent. On August 1, 1975, a magnitude 6.1 earthquake at Oroville
, California
, was attributed to seismicity from a massive earth-fill dam
and reservoir recently constructed and filled there.
The filling of the Katse Dam
in Lesotho
, and the Nurek Dam
in Tajikistan
is an example. In Zambia
, Kariba Lake may have provoked similar effects. The 2008 Sichuan earthquake
, which caused approximately 68 000 deaths, is another possible example. An article in Science
suggested that the construction and filling of the Zipingpu Dam may have triggered the earthquake.. However, researchers have been denied access to seismological and geological data to examine the cause of the quake further.
Some experts worry that the Three Gorges Dam
in China
may cause an increase in the frequency and intensity of earthquakes.
leaves voids that generally alter the balance of forces in the rock. These voids may collapse producing seismic waves and in some cases reactivate existing faults causing minor earthquakes. Natural cavern collapse forming sinkhole
s would produce an essentially identical local seismic event.
(EGS), a new type of geothermal power
technologies that do not require natural convective hydrothermal resources, are known to be associated with induced seismicity. EGS involves pumping fluids at pressure to enhance or create permeability through the use of hydraulic fracturing
techniques. Hot dry rock (HDR) EGS actively creates geothermal resources through hydraulic stimulation. Depending on the rock properties, and on injection pressures and fluid volume, the reservoir rock may respond with tensile failure, as is common in the oil and gas industry, or with shear failure of the rock's existing joint set, as is thought to be the main mechanism of reservoir growth in EGS efforts.
HDR and EGS systems are currently being developed and tested in Soultz-sous-Forêts (France), Desert Peak and the Geysers
(U.S.), Landau (Germany),and Paralana and Cooper Basin (Australia). Induced seismicity events at the Geysers geothermal field in California has been strongly correlated with injection data. The test site at Basel, Switzerland, has been shut down due to induced seismic events.
Researchers at MIT believe that seismicity associated with hydraulic stimulation can be mitigated and controlled through predictive siting and other techniques. With appropriate management, the number and magnitude of induced seismic events can be decreased, significantly reducing the probability of a damaging seismic event.
Induced seismicity in Basel
led to suspension of its HDR project. A seismic hazard evaluation was then conducted, which resulted in the cancellation of the project in December 2009.
Earthquake
An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves. The seismicity, seismism or seismic activity of an area refers to the frequency, type and size of earthquakes experienced over a period of time...
s and tremors that are caused by human
Human
Humans are the only living species in the Homo genus...
activity that alters the stresses and strains on the Earth's crust
Crust (geology)
In geology, the crust is the outermost solid shell of a rocky planet or natural satellite, which is chemically distinct from the underlying mantle...
. Most induced seismicity is of an extremely low magnitude
Richter magnitude scale
The expression Richter magnitude scale refers to a number of ways to assign a single number to quantify the energy contained in an earthquake....
. A few sites regularly have larger quakes, such as The Geysers
The Geysers
The Geysers is a complex of 22 geothermal power plants, drawing steam from more than 350 wells, located in the Mayacamas Mountains north of San Francisco, California.The largest in the world, the Geysers has...
geothermal plant, which in the past 5 years has averaged 2 M4 events and 15 M3 events every year.
Reservoirs
The mass of water in a reservoir alters the pressurePressure
Pressure is the force per unit area applied in a direction perpendicular to the surface of an object. Gauge pressure is the pressure relative to the local atmospheric or ambient pressure.- Definition :...
in the rock
Rock (geology)
In geology, rock or stone is a naturally occurring solid aggregate of minerals and/or mineraloids.The Earth's outer solid layer, the lithosphere, is made of rock. In general rocks are of three types, namely, igneous, sedimentary, and metamorphic...
below and through fissures in the rocks, lubricates the fault, which can trigger earthquakes. Reservoir-induced seismic events can be relatively large compared to other forms of induced seismicity. The first case of reservoir induced seismicity occurred in 1932 in Algeria’s Oued Fodda Dam
Oued Fodda
Oued Fodda is a town and commune in Chlef Province, Algeria. According to the 1998 census it has a population of 36,187.-References:...
. Unfortunately, understanding of reservoir induced seismic activity is very limited. However, it has been noted that seismicity appears to occur on dams with heights larger than 100 meters. The extra water pressure created by vast reservoirs is the most accepted explanation for the seismic activity. Induced seismicity is usually overlooked due to cost cutting during the geological surveys of the locations for proposed dams. Once the reservoirs are filled, induced seismicity could occur immediately or with a small time lag.
The 6.3 magnitude 1967 Koynanagar Earthquake
1967 Koynanagar earthquake
1967 Koynanagar Earthquake is the earthquake that occurred in and around Koynanagar town in Maharashtra in 1967. On 11 December 1967 a 6.5 magnitude earthquake hit Koynanagar near the site of Koyna dam. The earthquake claimed at least 180 human lives and injured over 1500 people. The earthquake...
occurred in Maharashtra
Maharashtra
Maharashtra is a state located in India. It is the second most populous after Uttar Pradesh and third largest state by area in India...
, India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
with its epicenter, fore and aftershocks all located near or under the Koyna Dam reservoir. 180 people died and 1,500 were left injured. The effects of the earthquake were felt 230 km away in Bombay with tremors and power outages. During the beginnings of the Vajont Dam
Vajont Dam
The Vajont Dam is a disused dam, completed in 1959 in the valley of the Vajont river under Monte Toc, 100 km north of Venice, Italy...
in Italy, there were seismic shocks recorded during its initial fill. After a landslide almost filled the reservoir in 1963, causing a massive flooding and around 2,000 deaths, it was drained and consequently seismic activity was almost non-existent. On August 1, 1975, a magnitude 6.1 earthquake at Oroville
Oroville, California
Oroville is the county seat of Butte County, California. The population was 15,506 at the 2010 census, up from 13,004 at the 2000 census...
, California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
, was attributed to seismicity from a massive earth-fill dam
Oroville Dam
Oroville Dam spans the Feather River about northeast of the city of Oroville, California. It forms Lake Oroville, which stores water for irrigation, flood control, municipal water supply and hydroelectricity generation in California's Sacramento Valley. The dam lies in the foothills of the Sierra...
and reservoir recently constructed and filled there.
The filling of the Katse Dam
Katse Dam
The Katse Dam, a concrete arch dam on the Malibamat'so River in Lesotho, is Africa's second largest dam....
in Lesotho
Lesotho
Lesotho , officially the Kingdom of Lesotho, is a landlocked country and enclave, surrounded by the Republic of South Africa. It is just over in size with a population of approximately 2,067,000. Its capital and largest city is Maseru. Lesotho is a member of the Commonwealth of Nations. The name...
, and the Nurek Dam
Nurek Dam
The Nurek Dam is an earth fill embankment dam on the Vakhsh River in the central Asian nation of Tajikistan. Construction of the dam began in 1961 and was completed in 1980, when Tajikistan was still a republic within the Soviet Union. At it is currently the tallest dam in the world...
in Tajikistan
Tajikistan
Tajikistan , officially the Republic of Tajikistan , is a mountainous landlocked country in Central Asia. Afghanistan borders it to the south, Uzbekistan to the west, Kyrgyzstan to the north, and China to the east....
is an example. In Zambia
Zambia
Zambia , officially the Republic of Zambia, is a landlocked country in Southern Africa. The neighbouring countries are the Democratic Republic of the Congo to the north, Tanzania to the north-east, Malawi to the east, Mozambique, Zimbabwe, Botswana and Namibia to the south, and Angola to the west....
, Kariba Lake may have provoked similar effects. The 2008 Sichuan earthquake
2008 Sichuan earthquake
The 2008 Sichuan earthquake or the Great Sichuan Earthquake was a deadly earthquake that measured at 8.0 Msand 7.9 Mw occurred at 14:28:01 CST...
, which caused approximately 68 000 deaths, is another possible example. An article in Science
Science (journal)
Science is the academic journal of the American Association for the Advancement of Science and is one of the world's top scientific journals....
suggested that the construction and filling of the Zipingpu Dam may have triggered the earthquake.. However, researchers have been denied access to seismological and geological data to examine the cause of the quake further.
Some experts worry that the Three Gorges Dam
Three Gorges Dam
The Three Gorges Dam is a hydroelectric dam that spans the Yangtze River by the town of Sandouping, located in the Yiling District of Yichang, in Hubei province, China...
in China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
may cause an increase in the frequency and intensity of earthquakes.
Mining
MiningMining
Mining is the extraction of valuable minerals or other geological materials from the earth, from an ore body, vein or seam. The term also includes the removal of soil. Materials recovered by mining include base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale, rock...
leaves voids that generally alter the balance of forces in the rock. These voids may collapse producing seismic waves and in some cases reactivate existing faults causing minor earthquakes. Natural cavern collapse forming sinkhole
Sinkhole
A sinkhole, also known as a sink, shake hole, swallow hole, swallet, doline or cenote, is a natural depression or hole in the Earth's surface caused by karst processes — the chemical dissolution of carbonate rocks or suffosion processes for example in sandstone...
s would produce an essentially identical local seismic event.
Extraction of fossil fuels and disposal of hydraulic fracturing waste
Fossil fuel extraction can generate earthquakes. Hydraulic fracturing of natural gas wells produces large amounts of waste water. This contaminated water is often pumped into salt water disposal (SWD) wells. The weight and lubricity of this waste water has been shown to trigger earthquakes.Geothermal energy
Enhanced geothermal systemsEnhanced geothermal systems
Enhanced Geothermal System is a new type of geothermal power technology that does not require natural convective hydrothermal resources. Until recently, geothermal power systems have exploited only resources where naturally occurring heat, water, and rock permeability are sufficient to allow...
(EGS), a new type of geothermal power
Geothermal power
Geothermal energy is thermal energy generated and stored in the Earth. Thermal energy is the energy that determines the temperature of matter. Earth's geothermal energy originates from the original formation of the planet and from radioactive decay of minerals...
technologies that do not require natural convective hydrothermal resources, are known to be associated with induced seismicity. EGS involves pumping fluids at pressure to enhance or create permeability through the use of hydraulic fracturing
Hydraulic fracturing
Considerable controversy surrounds the current implementation of hydraulic fracturing technology in the United States. Hydraulic fracturing, or fracking, is the process of utilizing pressurized water, or some other liquid, to fracture rock layers and release petroleum, natural gas, or other...
techniques. Hot dry rock (HDR) EGS actively creates geothermal resources through hydraulic stimulation. Depending on the rock properties, and on injection pressures and fluid volume, the reservoir rock may respond with tensile failure, as is common in the oil and gas industry, or with shear failure of the rock's existing joint set, as is thought to be the main mechanism of reservoir growth in EGS efforts.
HDR and EGS systems are currently being developed and tested in Soultz-sous-Forêts (France), Desert Peak and the Geysers
The Geysers
The Geysers is a complex of 22 geothermal power plants, drawing steam from more than 350 wells, located in the Mayacamas Mountains north of San Francisco, California.The largest in the world, the Geysers has...
(U.S.), Landau (Germany),and Paralana and Cooper Basin (Australia). Induced seismicity events at the Geysers geothermal field in California has been strongly correlated with injection data. The test site at Basel, Switzerland, has been shut down due to induced seismic events.
| Site | Maximum Magnitude |
|---|---|
| Cerro Prieto Cerro Prieto Cerro Prieto is a small rural town located in the county of La Misión in the northwestern part of the Mexican state of Hidalgo.... , Baja California, Mexico |
7.2 |
| The Geysers, United States | 4.6 |
| Cooper Basin, Australia | 3.7 |
| Basel, Switzerland | 3.4 |
| Rosemanowes Quarry Rosemanowes Quarry Rosemanowes Quarry, near Penryn, Cornwall, United Kingdom, was the site of an early experiment in extracting geothermal energy from the earth using hot dry rock technology.-Geothermal energy research project:... , United Kingdom |
3.1 |
| Soultz-sous-Forêts, France | 2.9 |
Researchers at MIT believe that seismicity associated with hydraulic stimulation can be mitigated and controlled through predictive siting and other techniques. With appropriate management, the number and magnitude of induced seismic events can be decreased, significantly reducing the probability of a damaging seismic event.
Induced seismicity in Basel
Induced seismicity in Basel
Induced seismicity in Basel led to suspension of its hot dry rock enhanced geothermal systems project. A seismic-hazard evaluation was then conducted, resulting in the cancellation of the project in December 2009. Basel, Switzerland sits atop a historically active fault and most of the city was...
led to suspension of its HDR project. A seismic hazard evaluation was then conducted, which resulted in the cancellation of the project in December 2009.
External links
- Map of reservoir-induced earthquakes at International Rivers
- IASPEI's Triggered and Induced Seismicity Working Group