As many developing countries are rushing to build dams to provide much-needed energy to large populations, many are warning that dams are a major cause of earthquakes.
Essentially, it is believed that the increased reservoir of water behind dams "lubricates" faults that already exist yet have remained in place due to high friction. The high-pressure reservoir water that gets into the fault reduces this friction, allowing the rocks to slip, which causes the earthquake.
Dr. V.P. Jauhari:
"The most widely accepted explanation of how dams cause earthquakes is related to the extra water pressure created in the micro-cracks and fissures in the ground under and near a reservoir. When the pressure of the water in the rocks increases, it acts to lubricate faults which are already under tectonic strain, but are prevented from slipping by the friction of the rock surfaces."
The 2008 Sichuan earthquake in China as well as the recent Yunnan Province quake are good examples.
Fact sheet by International Rivers
http://www.internationalrivers.org/files/attached-files/ris_final_lorez2.pdf
and cover page
http://www.internationalrivers.org/earthquakes-triggered-by-dams
China quake reignites debate on country's rush to build large dams
Washington Post
http://www.washingtonpost.com/world/asia_pacific/china-quake-reignites-debate-on-countrys-rush-to-build-large-dams/2014/08/06/9f72a087-27d3-48d5-b26f-435de700e04c_story.html
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