Like many of you, I was fast asleep in my bed when last Wednesday’s earthquake hit. I was convinced that my upstairs had neighbor fallen out of bed. Now that I was wide awake in the wee hours of the morning, I did what any red-blooded, course-overloading CMC sophomore would and pulled out my laptop to appease my habit of compulsively checking and replying to e-mails. I was about halfway through the 17th KLI Open House message when I felt it again—stronger. By the time I could whip my head around to glance outside, it was over. I knew this was something I’d felt before—in Guatemala, in Japan, in Missouri—it was something that always seemed to find a way to disrupt my REM sleep no matter where I decided to slumber: It was an earthquake. A Google search for recent earthquakes revealed that a 3.7 magnitude quake struck just a mile southwest of La Verne, while the 3.8 magnitude aftershock hit two miles east of Pomona. I recalled an urban legend recounted earlier in the week stating that a fault line ran just beneath Marks. I decided to look up the Southern California fault map to quell any doubts that there was a San Andreas-esque fault lying underneath my bed. This task proved more daunting than I could have ever imagined.
California‘s Department of Conservation shows a fault running right into Claremont that mysteriously disappears from the map as it approaches the colleges. Any attempt to enlarge it for greater detail provided a notice that “CGS has intentionally limited the ability to zoom in any further due to the resolution of this map”. Southern California’s Earthquake Data Center Map wasn’t much better, but at least it gave me a name for our trembling offender – the San Jose Fault, whose last significant earthquake, registering over 4.0 on the Richter scale, was in 1990. Interestingly, all the maps I found indicated that no fault line survey had been taken for the 5C area and reported that the data was simply missing. It didn’t add up; surely someone at some point must have plotted the whole thing.
I found a possible answer to my theory in a CBS San Francisco article that described a little-known piece of California legislature, the Alquist-Priolo Zoning Act, which prohibits new construction on active faults and requires disclosure if a property is sold with a known fault within fifty feet. In order for this to work, there has to be sufficient data proving that there is a fault under the building in question. In 2002, part of the Belmont Learning Center in the City of Los Angeles had to be torn down in the wake of the discovery of a fault directly underneath the building. Based on the raw map data posted on the CDC’s web site, the most recent surveys of Claremont were taken in the 1970s while neighboring communities such as Upland have had detailed studies completed as recently as the 1990s.
Finally, I found the original document from the surveyor who completed the most recent 1977 survey, Drew Smith. His final recommendation regarding the San Jose fault was that “on the basis of [current] literature, neither fault should be zoned under the [Alquist-Priolo Act], but that the fault should be further examined, and that only then would he feel comfortable making a recommendation on whether or not to zone the fault.” To the best of my knowledge, the further examination never occurred and thus the area holds the current distinction of “Area Not Evaluated”. Regardless, the commentary that accompanies the original document tells us that even in 1933, the fault could be “accurately traced” even though the fault plane is “nowhere exposed”.
After yet more digging, I found a tool on the Southern California Earthquake Center’s web site (a private organization) that plotted the entire map. It seems that their iteration of the fault has it running through Auen, Ducey, and across the fields on to Upland. So have the City of Claremont and CMC decided to sweep this under the rug, lest we lose our happiest college distinction? Are these tremors really the rumbles of secret coast-to-coast underground supersonic subways transporting the Illuminati from meeting to meeting? You be the judge. In the meantime, I’ll be disassembling the bookshelf dangling over my headboard.
Feel free to check it out yourself — just navigate to Claremont and click (Satellite) on the view menu to browse the map.