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High, Dry and Safe: In Search of the Perfect Site

Stuck SUV a Local Attraction for School Children

Stuck SUV a Local Attraction for School Children

The ideal spot for a seismic station is dry, quiet and safe from vandals and thieves. Seismometers record slight ground motions, allowing them to hear distant (and not so distant) earthquakes. But cars or even kids playing near a seismic station can produce ground vibrations that overwhelm the subtle sounds of earthquakes. Seismic stations include plenty of expensive, high-tech instruments that are worthless to the average person. But they also contain mundane items that can be useful, such as 12-volt batteries and insulated wiring, making theft a problem. And water is the enemy.

Malawi presented novel challenges for siting our stations. Our first priority was to find dry, secure locations to prevent damage and loss. As we drove into the Karonga region for the first time, our hearts sank; the epicentral region is low-lying and wet, small villages surrounded by rice paddies. Our arrival during the rainy season did not help.

But with a little hunting, we were able to find high and dry spots for most of our stations. We bumped along narrow village tracks in our rented 4×4, occasionally getting stuck on particularly muddy sections. Most of the dirt roads did not appear on our outdated maps, so we stopped regularly to ask for directions. When our Malawi colleagues explained that we were there to learn about the chindindindis (Tumbuka for earthquakes), they were eager to help!

Jim, Loveness and Hassan wait under mango tree for go-ahead to install station

Jim, Loveness and Hassan wait under mango tree for go-ahead to install station

In many parts of the world, safety and quiet can be achieved simultaneously simply by deploying stations in the middle of nowhere. This is not an option in densely populated Malawi, where one farming village abuts another. Main thoroughfares and small dirt roads alike were crowded with kids walking to school, villagers biking to town, and farmers grazing their goats and sheep. Instead, we sought out village police, teachers, and other officials for help finding safe spots. In some cases we hired guards to look after them.

We spent hours driving, inspecting sites and waiting to meet with officials. We normally skipped lunch, fueling ourselves instead on passion fruit-flavored Fantas and “puffs” (kids junk food akin to cheese doodles). But these efforts paid off – we found good sites for our equipment and started listening.

A Rough Start

Seismic stations awaiting transport.

Seismic stations awaiting transport.

The magnitude 6.0 earthquake that struck Malawi on Saturday night, December 19, spurred us into action. We had been closely following the earthquakes there, but this one confirmed the unusual nature of the seismic sequence. It also happened to be the most destructive. Leonard Kalindekafe, director of Malawi’s Geological Survey, asked us to come and monitor the ongoing quakes. However, mobilizing the needed equipment over the holidays turned out to be a challenge.

Within two days, we located ten seismometers: eight from the Incorporated Research Institutions for Seismology (IRIS), and two from Cindy Ebinger, a seismologist at University of Rochester in upstate New York. Cindy offered to send us her instruments, which we would carry on the plane with us. IRIS planned to ship their instruments directly to Malawi. On Christmas Eve, as we headed home to our families, everything seemed to be in order. We purchased plane tickets for Dec. 30, and planned to celebrate New Year´s Eve in Lilongwe, Malawi’s capital, with a couple of Carlsberg Specials at the Diplomat Pub. From there, we would head north to the epicenter.

Not all of it happened as planned. Shipments were canceled. Boxes went missing. Flights were changed. Shipping the IRIS equipment directly to Malawi required two weeks in transit, minimum. We considered wild back-up plans: “Let’s truck everything from Johannesburg to Malawi!” Just as quickly we rejected them: Johannesburg is 1,000 miles away, and would have required four border crossings.

More or less everything that could go wrong, did. The delays and false-starts were particularly frustrating since the clock was ticking; the rate of aftershocks declines steadily following a major earthquake. Each day of delay meant less information about the origin of the big earthquakes.

After two days of arranging and rearranging, hair pulling and hand wringing, we departed New York on New Year’s Day with equipment for five seismic stations, all of it packed into our checked luggage. We even crammed two seismometers into our carry-on backpacks; they passed through security at JFK apparently unnoticed. Eighteen hours later our eight 50-lb bags arrived at the VIP customs lounge in Lilongwe. Leonard helped speed us and our equipment through customs. Within an hour, we were in a 4×4 speeding towards Karonga. Almost nothing went right prior to our departure from JFK; from that point forward, nothing really went wrong.

East Coast Basalt and Carbon Sequestration - NPR Talk of the Nation

TRL Featured News - Fri, 01/08/2010 - 10:32
Basalt formations off the East Coast of the U.S. could suck up a billion tons of carbon dioxide, according to a new study. Paleontologist Paul Olsen, of Columbia University's Lamont-Doherty Earth Observatory, explains how to get the CO2 into the rocks, and why scientists believe it won't leak out.
Categories: TRL

Climategate, global warming, and the tree rings divergence problem - The Christian Science Monitor

TRL Featured News - Mon, 12/14/2009 - 16:19
Much discussion of the Climategate e-mails has centered on tricking tree ring data that may not confirm global warming. Quotes LDEO scientist Roseanne D’Arrigo and discusses her tree ring work in Alaska.
Categories: TRL



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