An odd stench occurred over a large expanse (10,000 square miles) of Southern California only days ago on Monday. Those concerned Californian residents, who called in about the malodorous odor mostly described it as being ” a sulfur like”, or “rotten egg smell”. The official response, from authorities on the matter

Earthquake swarm of 250 earthquakes ranging from 4.0-5..5 at the strongest occurred last week on August 26th 2012.The center of the activity is quite concentrated on the fault line that runs through Brawley and the Salton Sea (Salton Buttes) area. This area does have active geothermal prospecting, as well as a history of volcanic eruptions, although it has not occurred during historical time.

initially said it is either a fish die off in the Salton Sea which is responsible for the pervasive smell or overturning of the lake from strong southeast winds blowing across it from recent storms. Fortunately no health issues arose with pungent smell.The Salton Sea is some 150 miles E.S.E. from Los Angeles.

However what if it were volcanically linked?

Most definitely… Volcanic activity is possible,” said geologist Pat Abbott.

Abbott was part of a research group that collected footage of muddy pits and volcanic gases about 100 miles east on the southern end of the Salton Sea. The area is the home of four buttes that are several hundred feet tall.

The buttes are small volcanoes with an explosive past. Miles below them is a pool of magma that is 15 miles wide. About 8,000 years ago, the buttes erupted, causing magma to flow which cooled into obsidian rock.

The damage from those eruptions was limited to the surrounding area, but if a major earthquake hit along the San Andreas Fault, geologists said there could be trouble.”

However U.S.G.S. geophysical studies of seismic activity, of heat flow in the earth, and of magnetic anomalies in the area around the south end of the Salton Sea all suggest that active igneous and metamorphic processes

It all comes down to the Salton Sea, which lies to the east of San Diego. The Salton Sea lies directly on the San Andreas Fault and covers more than 350 square miles.  A big earthquake has hit the lake bed about every 180 years. But when officials started damming the Colorado River to reduce floods downstream (including in the Salton Sea), the moderate earthquakes stopped for the Salton. But seismologists think the damming stopped moderate stress-relieving earthquakes on the Salton. Now, they fear the pressure is building and the area could be as many as 100 years overdue for a mega-quake, measuring 7.5 or larger.

are now going on associated with an intrusive mass that lies below the sedimentary cover. The intrusion under the Salton Sea is thought to be a pluton, an arm or protrusion from a deeply buried molten magma. This intrusion is parallel to the axis of the Salton Trough. It is about 20 miles long by four miles wide, and is at least one to two miles thick. It lies within the upper 10,000 feet of the crust, and possibly as close as 4,000 feet from the surface. It is centered beneath the community of Niland, at the southeast shore of the Sea.

This pluton is acting upon the sedimentary fill, altering the rocks into a low grade metamorphic series under low-temperature/low-pressure metamorphism. Associated with the metamorphism of the rocks, chemical analysis of hot brines brought to the surface by deep thermal wells in the Imperial Valley and Mexico show that active ore formation is probably taking place around the pluton. This involves the concentration of sulfides of iron, lead, zinc and copper.

Previously on July 24th 2012 Lifeguards in Encinitas, California were first to report the strong, pungent odor at about 5 p.m. The odor was described as a gas-like smell rolling in off the ocean.

Soon after,911 was flooded with calls. Residents from the coast all the way to Rancho Bernardo and 4S Ranch reported experiencing the smell. Some complained of headaches and outdoor activities were canceled.

One Del Mar resident who did not want to be identified was inside the library in Cardiff at about 5 p.m. when the gas-like odor filled the entire building with the doors closed.

“There was none when I walked in that door and within 10 minutes, the entire library was filled,” she said.

Eventually, she got in her car and drove to try and get away from the smell. At about 5:30 p.m., the woman parked at San Dieguito County Park and took a photo of what she believes is some kind of aerosol compound she says fell from the sky and coated her car windows.
“I tried to wipe it and it was black and sticky and tried to put my window down and it smeared,” she said. She is convinced it was gas that was dispersing something with an oil component.