California quakes remind us of our ‘Big One’

Two big earthquakes hit southern California last  week,  renewing fears of the “Big One” that Californians  have  long  been warned about.  Fortunately, the earthquakes – magnitude-6.4 on Thursday  followed by magnitude-7.1 on Friday -- hit a sparsely populated area  18 kilometers from the city of Ridgecrest, but they were enough to damage some buildings, crack roads, and disrupt some water and gas lines  in an area from Sacramento City to Mexico in the south.

The  two earthquakes  were  not even on  the San Andreas Fault, a major crack beneath the earth that runs  along  Western California, alongside Los Angeles,  and cuts across  California’s thickly populated San  Bernardino County.  In 1994, a magnitude-6.7 earthquake  -- only a quarter as powerful as  the 7.1  second Ridgecrest  earthquake  -- killed 57 people a nd injured over 8,700, because it hit close to  LA. Today, the people of LA live in fear of the “Big One” – a magnitude-7.8  earthquake  which geologists said is long overdue.

We in the Philippines also have long lived  in fear of our own  magnitude-7.2  “Big One” which, it is said, could come at any time.  We  have  beneath  Bulacan, Metro Manila, Cavite, and Laguna  a “West Valley Fault” which caused a major earthquake in 1658 and,   it is feared, will snap again after some 400 years and cause a 7.2 earthquake in Metro Manila.

When  that  happens,  a study by the Japan  International Cooperation  Agency  said, the death  toll could reach 34,000, with 300,000 injured as many buildings collapse. It is for this  reason  that we have been holding annual  “Shake Drills,” with everyone asked to “Duck, Cover, and  Hold” under a table or other solid  support and protect one’s head  from  falling  objects.

Most  of the world’s earthquakes have occurred  on  the so-called  Pacific Ring of Fire, filled with so many  volcanoes  and  with  underground  earth masses  grinding  against each other. This  ring  goes around the Pacific --  from Alaska in the northeast, along the western coasts of North, Central, and  South America, to the  islands of the South Pacific, the islands of Southeast Asia, to  Japan, Kamchatka peninsula,  back  to Alaska.

Nearly  all  of the world’s most powerful  earthquakes have taken place along this Ring of Fire. The most powerful was a magnitude-9.5  that hit Chile  in 19
60,  followed by a magnitude-9.2 in Alaska  in 1964,  a magnitude-9.1 in Sumatra  in 2004, and another  magnitude-9.1 in Japan in 2011. Hundreds  of  weaker earthquakes have occurred  over the centuries. Only this Monday, a 6.9  earthquake  struck off the coast of Indonesia’s Sulawesi  island directly south of us.

Following  the two Ridgecrest  earthquakes last week, the people of California are on alert. We too should  continue  to be  on alert  for our own “Big One” by joining the annual exercise and taking  all the suggested  precautions, such as being ready with emergency food and medical kits.