Tuesday, March 2, 2010

Oil Drilling and Haiti’s Earthquake

By Glenroy Blanchette

HYC - Hydrocarbons and HYT - Hydrothermal deposits throughout Haiti. One of the poorest nations on Earth sitting on 1.5 trillion barrels of Black Gold.

On 12th January 2010, a Magnitude 7.0 earthquake occurred ten miles off the coast of Haiti and resulted in the deaths of over 200,000 inhabitants, millions made homeless, and hundreds of thousands dying without access to food, water, shelter and medical treatment.  It was more devastating than the Indian Ocean tsunamis and five times deadlier than the 1972 earthquake that destroyed Nicaragua’s capital.

The earthquake has prompted allegations about a possible link between the earthquake and oil drilling off the coast of Haiti. However, a certain section of the scientific community has dismissed any association between oil drilling and earthquakes of high magnitudes.  The United States Geological Survey (USGS) believes that oil drilling is not the cause of the few earthquakes that are triggered by humans but occur as a result of the injection of fluids into deep wells for secondary recovery of oil and the use of reservoirs for water supplies.

Scientists find oil by using geophysical techniques such as seismic reflection (bouncing sound waves off the various layers of the earth followed by drilling for the oil.  Drill holes can plunge down to depths of six miles.  Oil drilling in Haiti was done at depths of nearly two miles.

The January 12th earthquake occurred along the plate boundary region where the Caribbean plate is sliding past the North American plate.  The earthquake spanned some 35 miles along a fault system which runs east-west through Haiti, to the Dominican Republic in the east and Jamaica in the west.  The epicenter was located just 10 miles south-west of the Capital, Port-au-Prince.  The earthquake was very shallow - about six to ten miles below the surface.

In March 2008, during the 18th Geological Conference in Santo Domingo, five scientists presented a paper stating that a fault zone on the south side of Haiti posed "a major seismic hazard," and they predicted that a magnitude 7.2 earthquake would result if all of the strain along the fault were released in a single event.  The release of energy would need a trigger mechanism.  Would it be provided by oil drilling?

A New York Times report confirmed oil drilling sets off earthquakes and showed how oil drilling projects near San Francisco, USA, and Switzerland were shut down amid concerns they triggered damaging earthquakes.  In both instances, the drilling for oil involved the fracturing of hard rocks more than two miles deep.

According to a scientific study reported in the French magazine Science et vie, around 200 earthquakes have been triggered by human activity.  Of those 200, 10 were earthquakes above the magnitude of 5.0  Wired Science, corroborated these findings when it stated that human action can trigger much larger quakes along natural fault lines.  The pressures exerted along fault lines can shift the pattern of stresses in the earth’s crust.

The largest human-caused earthquake (M7.3) occurred near a natural-gas field in Uzbekistan, the Gazli. According to Russian scientists, the extraction of oil and natural gas in regions of high tectonic activity could trigger strong earthquakes.

It is also believed that the extraction of natural gas at the epicenter Banda Aceh facility was a probable man-made trigger for the M9.0 earthquake and accompanying tsunamis that killed more than 225,000 people in December of 2004.

However, seismologist James Agnew believes that the M9.0 earthquake was entirely natural because it occurred on a subduction zone many miles beneath the surface of the earth, much deeper than man has ever drilled.  The depth of the bore-hole was small compared to the 19 miles depth of the hypocenter (focus), and it was located under the ocean far from the drilling area – 155 miles SSE of Banda Aceh.  He also agued that the pressure release of oil is very small compared to the force that is necessary to move one plate under another.

Meanwhile, the exploration for geothermal energy is creating its own share of controversy.  In Nevis, geothermal energy exploration is being touted as the next best thing in energy production and distribution with its anticipated economic benefits.  However, all is not well with geothermal energy exploration.

According to an article published in the New York Times on 10 September 2009, government officials in Germany are reviewing the safety of a geothermal energy project that scientists believed set off an earthquake the previous month.  The epicenter was 500 yards from the drill site at the plant and at about the same depth (1.5 miles) as a steam bed that the plant was extracting heat from.

Another article published in the December 10, 2009 issue of the New York Times, reported that a $60 million project to extract geothermal energy from the hot bedrock beneath Basel, Switzerland, was shut down permanently after a government study concluded that earthquakes generated by the project were likely to cause millions of dollars in damage each year.  The project was suspended in late 2006 after it generated earthquakes that caused $9 million in damage to homes and other structures.

More recently, there has been heightened concern about induced seismicity involving new Engineered Geothermal Systems (EGS) technology which involves the deliberate fracturing of deep reservoir rock to create a permeable geothermal reservoir so that the Earth’s heat can be recovered more easily. Deep fracturing has been a routine practice in the oil and gas industry for many years.

The authorities in Nevis have stated that no seismic activity has been linked to geothermal exploration there.  In fact, the UWI Seismic Research Unit in Trinidad has found no correlation between the series of earthquakes which recently occurred in Nevis and the geothermal exploration project.  An official of West Indies Power (Nevis) Ltd., stated that the earthquake was 11 miles off the eastern coast of the island and its hypocenter was 22 miles deep.  The official also stated that the deepest hole that West Indies Power has drilled is 3,720 feet (0.7miles).  Can we rely on information provided by proponents of geothermal energy?

More often than not, big business is the driver behind drilling for oil and natural gas and geothermal energy exploration.  Short term economic considerations are usually given greater priority over safety issues and any association between earthquakes and oil and geothermal energy extraction is usually dismissed as unscientific.

However, the evidence remains inconclusive.  While the is some evidence of a strong association between earthquakes and human activities, there is no fully accepted model of just what does finally set an earthquake in motion.  The USGS and other scientific bodies are presently investigating the trigger mechanisms for earthquake.

Whether or not earthquakes are caused by oil drilling or geothermal energy exploration, there is one thing that remains unmistakably clear – the Haitians were not prepared to respond to the earthquake event. Instead of running away from their homes and buildings, Haitians ran for cover during the quake as if it were a hurricane.  Port-au-Prince had not experience a serious earthquake in the last 239 years.

What lessons can we learn from Haiti’s experience?  St. Kitts and Nevis, like the other countries of the Eastern Caribbean, are at risk of tectonic earthquakes.  According to data compiled by the Seismic Research Unit in Trinidad, earthquake risk is highest in the Leeward Islands and Trinidad.  In light of the fact that earthquake prediction is not an exact science, our citizens must become prepared for any serious earthquake event. While geothermal energy can provide a clean, reliable and inexhaustible 24/7/365 power supply, appropriate actions such as the establishment of monitoring protocols, public education and awareness need to be taken to minimize any risk to public safety.


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