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WASHINGTON Nike Air Max 2018 Sale Online , Aug. 2 (Xinhua) -- The destructive power released by human-induced and naturally occurring earthquakes in the central United States is actually "indistinguishable," a U.S. study said Wednesday.


The finding, published in the U.S. journal Science Advances, contradicted previous observations suggesting that induced earthquakes exhibit weaker shaking than natural ones.


Earthquakes in the central U.S. have increased over the past 10 years due to the expansion of unconventional oil and gas operations that discard wastewater by injecting it into the ground.


About three million people in Oklahoma and southern Kansas live with an increased risk of experiencing induced earthquakes.


A key question is whether these induced earthquakes excite ground motions that are substantially different than those of naturally occurring earthquakes.


To answer this question, the new study used available instrumental recordings to estimate the stress drop -- the difference between the stress across a fault before and after an earthquake -- of 39 moderate-magnitude induced and natural earthquakes in the central U.S and in eastern North America.


Once the faulting mechanism and the depth of the quakes are accounted for Nike Air Max 2017 Sale Online , the stress drops of induced and natural earthquakes in the central U.S. share the same characteristics, results showed.


"Our study shows that induced earthquakes and natural earthquakes in the central U.S. are inherently similar, and we can predict the damaging effects of induced earthquakes using the same framework as natural earthquakes," said first author Yihe Huang, an assistant professor at the University of Michigan.


The study also found that naturally occurring earthquakes in the eastern North America may lead to stronger shaking than natural earthquakes in the central United States.


That's because most eastern earthquakes occur on reverse faults Nike Air Max 90 Sale Online , while most central U.S. induced and natural earthquakes occur on strike-slip faults. Reverse-faulting earthquakes typically have stronger shaking than strike-slip earthquakes.


The scientists said that the types of rocks being exploited by unconventional oil and gas recovery in the U.S. and Canada can be found all over the world, making the results of this study widely applicable.


"As we can learn better practices, we can help ensure that the hazards induced earthquakes pose can be reduced in other parts of the world as well," added co-author William Ellsworth, co-director of Stanford University's Center for Induced and Triggered Seismicity.


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HOUSTON Nike Air Max Sale Online , May 4 (Xinhua) -- The world's largest oil and natural gas trade show, the Offshore Technology Conference (OTC), kicked off in the U.S. energy hub of Houston on Monday with a visible presence of emerging Chinese companies.


The annual event, a conference and exhibition, was unveiled Monday morning in the cavernous complex of NRG Park near downtown Houston. Thousands of professionals from around the world braved the Texas heat to attend the industry gala.


The show has apparently felt the pinch from the plunging oil prices as quite a few OTC veterans told Xinhua they saw less visitors and exhibitors coming this year.


OTC Chairman Ed Stokes Air Max 2018 Sale Online , however, remained optimistic, saying though he did not have the attendance number right now but this year's exhibition floors are the largest ever -- enough to cover around 12 American football fields.


"The drop in oil price may have some impact (on OTC), but it doesn't affect the quality of the programs we have. The people here to speak are top class and the equipment and technologies on display are top notch," Stokes said.


Stokes noticed the increasing number of Chinese companies coming to the show. Among some 2 Air Max 2017 Sale Online ,700 exhibitors, about one tenth are from China.


"We have more than 130 countries represented here. China is the second largest economy in the world and also a big player in oil industry," said Stokes. "So it's very important for Chinese companies to be here to advertise themselves and network with others."


Cao Minghui, an operation director with Sinopec Oilfield Services Corporation, admitted to Xinhua that as a latecomer in the industry Air Max 90 Sale Online , China still lags behind in many areas, especially in core technologies, but "we boast some leading stuff too."


"We are here to show our strength," Cao said while pointing to several simulated models of rig platforms, "we are eager to expand our overseas market."


Yang Yun Air Max Sale Online , executive vice president of China Offshore Oil Engineering Co., was more ambitious. "During previous years, we were here more to learn from others, but this year we are more focused on marketing our own products and landing overseas clients," he said.


The four-day-long show includes exhibitions Nike Air Max 2018 Sale Clearance , panel discussions by high-profile speakers and technical sessions. Started in 1969, it showcases leading-edge technology for offshore drilling, exploration, production, and environmental protection.


LOS ANGELES Nike Air Max 2017 Sale Clearance , Aug. 27 (Xinhua) -- Lionsgate's "The Hitman's Bodyguard" continued to lead the gloomy North American box office for the second weekend in a row, bringing in an estimated 10.05 million U.S. dollars.


This weekend's catastrophic overall tally in North American box office is the worst in at least three years, winding up at around 65 million U.S. dollars.


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