Wednesday, October 28, 2009

Megaquake in Seattle?

Megaquake Looms Over Seattle from Discovery News

Southern California isnt the only part of the US that lives in fear of a major earthquake. This new study suggests that a major earthquake in the Pacific Northwest might occur much closer to major population centers in the Seattle area than previously thought. As Southern Californians, we all know what kind of dangers earthquakes can pose near major metropolises.

The Cascadia fault in Washington is a different type than the faults we have in Southern California. It's a thrust fault - where two continental plates are converging, and one slides underneath the other. As they grind along each other, they can produce earthquakes. In Southern California, our major faults are transform faults - where two plates are sliding past each other. Thrust faults typically generate deeper and more powerful earthquakes than transform faults - while the study estimates a 9.0 magnitude quake on the Cascadia fault, the largest that the San Andreas fault can support in this area is about 8.6, about 2.5x less energetic.

The Northridge earthquake of 1994 was also triggered along a much smaller thrust fault that ran underneath the Los Angeles area. Although that quake was only of moderate intensity (6.7 magnitude), it exemplifies the type of damage that an earthquake along a thrust fault can wreak near a major city.

This might actually be good news, though, for those not in the immediate earthquake area - the new "hot zone" for the fault has moved from offshore to under the Olympic peninsula. A suboceanic earthquake would pose a higher risk of generating devastating tsunamis that would propagate up and down the Pacific seaboard; the last major earthquake on the fault, around the year 1700, caused destructive tsunami waves that traveled as far away as Japan.

Wednesday, October 7, 2009

Mammoth Discovery

Baby mammoth yields secrets after 40,000 years in Siberian Tundra
from the Times UK

A woolly mammoth was discovered in 2007 in the Arctic tundra, and is making news this week. What's truly fascinating about this is the age of the mammoth - only a month old when she died. She was amazingly well preserved, as well; the best-preserved woolly mammoth mummy yet found. Her eyes, her organs, even the food in her stomach were all preserved by the clay that trapped and suffocated her.

Scientists hope that this exceptional preservation will let them explore details that might shed new light on mammoth physiology and the changing environment of her times - about 40,000 years ago.

Lyuba is a woolly mammoth - different than the Colombian mammoths that inhabited the Diamond Valley area in the Pleistocene. They lived in colder, more northern, tundra-like environments, and grew the shaggy wool coat that gives them their name. Colombian mammoths inhabited more temperate lower-latitude grasslands, and while they had some hair, it was not the full, thick coat you see in Woolly mammoths.

One similarity between Lyuba and mammoths in this region, though, is how she was first found. She was discovered by a Siberian reindeer farmer, having eroded partway out of a riverbank. Similar finds pop up in Southern California every year - mammoth tusks or horse bones that may have lain under the surface for millenia, peeking out after a rainstorm or catching the toe of some lucky hiker passing by. Fortunately for paleontologists, the Siberian farmer got in contact with scientists before she was tampered with any more, and they were able to excavate Lyuba carefully to ensure this unique discovery will tell us all it can about the world of the woolly mammoth.


Thursday, October 1, 2009

Backyard Monsters!

The new exhibit is up! Backyard Monsters opened last Saturday, and even though it was a whirlwind installation, everything found a place and was up and operational in time. Getting the dragonfly hung in place was a particular challenge, but it was worth the effort and looks great, hovering over the entrance to the exhibit with its 10 foot wingspan.

The exhibit really fills in the gallery with a lot of information and entertainment. The giant robot insects are impressive, of course - when we first turned them on, I was impressed by how nuanced and complex their movement was. They definitely are more than just bugs on a stick!

I was equally impressed by the diversity of the specimen collection. There are dozens of very impressive specimens of insects from all over the world. Beautiful, iridescent Morpho butterflies, spiny walking sticks almost as long as your arm, giant bees, and even bigger tropical beetles...the exhibit has just about every cool bug you can think of. It'll make you glad you live in Southern California, and dont ever have to worry about finding one on your pillow in the morning!

The interactive exhibits have a lot of good information and really make it easy to understand how these bugs are put together and what makes them work. The robobugs are lots of fun to play with, too!

I think this exhibit is going to be a tremendous success here at the Western Center. The schoolkids that have been through the exhibit love it right away, and they're learning a lot as they go through. If you're close enough to make the drive to Hemet, we really hope you'll come out and visit, you cant really appreciate how impressive it is until you see it for yourself!