WebProNews

Tag: San Andreas Fault

  • California Expected to Set Water Restrictions

    In an attempt to help curb the impact of a three-year drought, California is likely to soon issue a first-time mandatory water restriction.

    The California State Water Resources Control Board is expected to pass the emergency measure Tuesday, as reservoirs across the state and in the region are dwindling. Officials have stated that the new mandate would ban practices such as washing cars without hoses equipped with a shut-off nozzle, and allowing sprinkler water to run off lawns onto streets. Maximum fines for violations would be $500, enforceable by local water agencies.

    California’s Lake Oroville presently stands at 39 percent capacity, while Nevada’s Lake Mead, which is the largest supply of drinking water in the Southwest, has sunk to its lowest level since it began filling in the 1930s after the completion of the Hoover Dam.

    Lake Oroville looking low:

    California Governor Jerry Brown had urged all Californians to conserve water voluntarily in January, in hopes of cutting wasteful use by twenty percent. A statewide water survey conducted in May revealed that voluntary efforts had yielded savings of only five percent. State and federal agencies have sharply reduced water shipments in California, with farmers, ranchers and some cities in the northern part of the state feeling the greatest effects.

    Felicia Marcus, chairwoman of the California water board, remarked, “There is a need for people to take more dramatic action. We are saying: ‘For heaven’s sake, don’t waste water.’”

    The water shortage in California has also affected seismic activity along the San Andreas Fault. The fault, a continental transform that runs roughly 810 miles through California, is being affected by irrigation practices in the area, according to a study by Geologist Colin Amos from Western Washington University.

    Satellite data has shown that groundwater in and near the California Central Valley has been depleted more quickly than it can be re-filled over the past decade, and Amos’ study related the water in association to the mountains in the area as being akin to a weight sitting atop a piece of bendable wood. As the water is depleted, its weight is lifted, which in turn pushes the mountains to rise from the Earth’s crust.

    Amos confirmed that seasonal fluctuations in water usage have coincided with minor earthquakes around the San Andreas Fault, and that new developments for water usage and natural groundwater retention need to be implemented.

    Image via Wikimedia Commons

  • San Andreas Fault: Could Drought Make It Worse?

    The drought in California is causing a lot of problems for residents, most of these problems are obvious, but one is harder to see. The drought has caused Californians to take water from underneath the Central Valley. This has caused the area to rise up at least six inches since it was first pumped for water in 1860.

    The rising land and depleted water is also causing some not so pleasant effects. More and more earthquakes have been occurring in California and a recent study shows that the pumping could be causing more stress on the San Andreas Fault and lead to more earthquakes in the future.

    “The magnitude of these stress changes is exceedingly small compared to the stresses relieved during a large earthquake,” lead researcher Colin Amos, a geologist at Western Washington University, said.

    Most Californians are used to dealing with small earthquakes, but scientists have warned for years that a giant earthquake capable of killing 1,800 people and causing $200 billion in damage could also occur along the fault line sometime in the near future.

    This has caused many people to wonder what they can do to prevent such quakes from occurring and further stressing the fault. According to Amos, the damage is already done and cannot be reversed.

    “These earthquakes are likely to occur no matter what humans do,” Amos said.

    The study has also offered a unique view into earthquake hazard causes.

    “This study shows that human-induced changes are significant and must be considered in earthquake hazard analyses,” said Paul Lundgren, a geophysicist at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California.

    “The key aspect to keep in mind is that while they can estimate that the unclamping of the San Andreas Fault will promote future seismicity there, they do not know what is the current absolute state of stress on the fault nor how much additional stress accumulation is required to generate the next large earthquake,” Lundgren said.

    Do you think the pumping will lead to more or bigger earthquakes and what else can be done about the California drought?

    Image via Wikimedia Commons

  • San Andreas Fault Affected by Irrigation

    The San Andreas Fault, a continental transform that runs roughly 810 miles through California, is being affected by irrigation practices in the area, according to a study by Geologist Colin Amos from Western Washington University.

    Readings from GPS technology have shown that water levels in the San Joaquin Valley aquifer have lowered and that the mountains nearby have simultaneously risen, which has caused the San Andreas Fault to undergo changes in pressure levels. Though, Amos points out that stress changed due to lower water levels are minuscule compared to pressure-changes seen on the fault before a major earthquake.

    The San Andreas Fault forms a tectonic boundary between the Pacific Plate and the North American Plate, and a study in 2006 concluded that the fault has achieved a level of stress sufficient to facilitate the next “big one”, or an earthquake greater than magnitude 7.0. In 1906, a rupture in the San Andreas Fault caused a magnitude 7.7-8.25 earthquake in San Francisco that destroyed almost 80% of the city and killed 3,000 people. The earthquake and resulting fire are regarded as one of the worst natural disasters in the history of the United States.

    Here is a small documentary on San Andreas:

    Amos’ study, which was published in Nature journal on Wednesday, suggests that human-related activities can cause the San Andreas Fault to unclamp, resulting in the possibility of greater future volatility. At present, seismologists have found that the San Andreas Fault produces a magnitude 6.0 earthquake approximately once every 22 years. The last occurred in the Parkfield area in 2004.

    Satellite data has shown that groundwater in and near the California Central Valley has been depleted more quickly than it can be re-filled over the past decade, and Amos’ study related the water in association to the mountains in the area as being akin to a weight sitting atop a piece of bendable wood. As the water is depleted, its weight is lifted, which in turn pushes the mountains to rise from the Earth’s crust.

    Amos confirmed that seasonal fluctuations in water usage have coincided with minor earthquakes around the San Andreas Fault, and that new developments for water usage and natural groundwater retention need to be implemented.

    Image via Wikimedia Commons

  • San Andreas Fault Stressed By Irrigation

    On Wednesday, the journal of Nature released their most recent findings regarding the San Andreas Fault.

    According to the study, excessive irrigation could be aggravating the fault, causing more frequent earthquakes. GPS readings have shown that parts of the floor of the San Joaquin Valley have been diminishing while the nearby mountains are being lifted higher. These motions are causing stress on the nearby faults, including the San Andreas.

    Colin Amos, the lead researcher and a geologist at Western Washington University, wrote an email about their findings. “The magnitude of these stress changes is exceedingly small compared to the stresses relieved during a large earthquake,” he said.

    Paul Lundgren of the NASA Jet Propulsion Laboratory, who did not take part in the research, explained that human activities “can cause significant unclamping of the nearby San Andreas Fault system.”

    Shockingly, in the past 100 years, the amount of groundwater that has been lost through irrigation in the Central Valley is equivalent to the amount of water in Lake Tahoe. The current drought that has bombarded California has also contributed to the loss of groundwater, as the community is having to tap into their supply.

    The San Andreas Fault is one of the largest in California, running approximately 800 miles from just north of San Francisco to the Salton Sea near the United States/Mexico border.

    Scientists have revealed that if a magnitude 7.8 earthquake were to occur near the southern part of the fault, it could cause the deaths of nearly 1,800 people and $200 billion in damages.

    Image via Wikimedia Commons