Koror, Palau

Latitude: 7°20'31.00"N
Longitude: 134°28'45.00"E

           Quick poll: Who among you, of my scant readership, has ever heard of the country called Palau?

           No one, right?


© 2010 Matthias Schulz

           Well, neither had I. While struggling to find a suitable location near an oceanic subduction boundary (more on that later), I just barely noticed this tiny island jutting out of the Pacific, several hundred miles to the east of the Philippines. Amazing thing, this Google Earth. It was pretty much on a whim that I decided to make it the second stop of my tectonic journeys around the world. But lo and behold, after a week in Nepal, befriending Sherpas and reveling in the abundance of gorgeous temples, here I am in the city of Koror, only slightly jet-lagged this time. And my room in the Palau Water Paradise Hotel and Spa overlooks a life-size postcard! Tropical forests roll into the distance; palm trees frame the beach; waves tumble onto the ivory sands; coral atolls speckle the sparkling sapphire sea. There are even huts with thatched roofs inhabited by native families, friendly folk with olive skin and white smiles. Not a lot of urbanity, even in the heart of Koror, but that would only mar this sunny perfection. Really, it's about as idyllic as it gets - like Hawaii, only less crowded. All I need to complete this picture is the twang of a ukulele.

           So where's the science in this? What does this have to do with plate tectonics?
           Some years ago, Rep. Hank Johnson of Congress stated his fear that the small island of Guam would tip over and capsize if overpopulated. Let me clarify something for you: an island is not a floating land mass bobbing in the ocean like a cork. It is the summit of an underwater mountain that has jutted out from the surface of the water, mountains that would dwarf Everest if their bases were at sea level. None of them are planning to capsize anytime soon.
          With that in mind, Palau is located right where two oceanic plates, the Philippine Sea and the Caroline, are converging. This is somewhat different than the interaction between the Indo-Australian and Eurasian plates, because the Caroline plate is actually being forced beneath the Philippine plate, or subducting. The crack between the two becomes a deep-sea trench - the Palau Trench. As the Caroline plate sinks deeper, the water it brings lowers the melting point of the mantle, or the layer of the Earth beneath the crust. Melting mantle becomes magma, and this magma rises up through the Philippine plate, cools, and forms a volcano. A chain of such volcanoes are formed, in fact, and this feature is called a volcanic island arc. If a tip sticks out of the water, it becomes an island, and Palau is one such tip. Yes, I am vacationing on a volcano right now - but so is anyone in Hawaii or Indonesia, just to name a few.

          That, my friends, is a subduction boundary. Your brains fried? Maybe I should just explain with a nice diagram:

© 1984 Tasa Graphic Arts, Inc.

          Like Kathmandu, Palau's location subjects it to frequent earthquake activity. A sizable quake - 4.6 on the Richter scale - occurred only last month, though nothing devastating has happened for a while. And the island itself is dormant, a good thing too, because this trip is supposed to be a learning experience, not a near-death one. Could you imagine how terrifying it would be if you were chilling on some island and it BLEW UP?

          That's all for today, folks. The sea beckons - I'm off to snorkel in the shallows and see fish and turtles and all that wonderfulness. Ak morolung!