Tuesday, February 24, 2009

Geological Holy Lands

Ol' Geotripper is hosting this month's Accretionary Wedge (#16, by the way), the theme of which is "Kickass Geology Spots That You Must Visit" (I paraphrased that, slightly). Anyway, here is my submission:

The Wadi Al-Hitan, in Egypt!

The Wadi Al-Hitan is a UNESCO World Heritage Site, recognized as a place of peculiar Scientific Interest, Cultural Importance, and Scenic Loveliness. I had the opportunity to do a couple weeks of fieldwork down there late last year, and I can attest that the Wadi Al-Hitan is, indeed, completely kickass.

The Wadi Al-Hitan, located in the Western Desert of Egypt, records a phase of Bartonian-Priabonian (Mid-Late Eocene, ~38 - 33 Mya) marginal marine to offshore shelfal deposition. Fine sands, silt, and mud dominate the stratigraphy, and the resultant wind erosion has exposed some spectacular outcrop. The extremely dry climate means that we don't have to contend with that pesky green stuff that grows all over rocks elsewhere; combined with the fact that there hasn't really been any post-depositional tectonism or tilting, and you get a beautiful stratigraphic story laid out for miles and miles at your feet, ready to be walked out, described, and correlated (just bring lots of water, though).

As gorgeous as all that rock is, the wonderful stratigraphy isn't the reason the UN designated the Wadi Al-Hitan a world heritage site. Rather, this is:

That's right. Wadi-Al Hitan (which means "Valley of the Whales" hint hint hint) has a ridiculous amount of vertebrate fossils preserved in it. Among these are thousands of whales, including totally rad specimens of Basilosaurus and Dorudon. The picture above is part of a Dorudon jaw that we found while wandering around the dunes. By the way, those little pits at the end? Those are WHISKER HOLES.

A lot of our current understanding of the evolution of whales actually comes from fossils in this area; on a side note, I would point out that the occurrence of these critters is stratigraphically predictable, which is the point of a soon-to-be-out Palaios paper that I'll talk about soon.

Of course, it's not all about vertebrates, mind you! There are lots of kick-ass inverts, too, including heart urchins...

...and trace fossils!

The Egyptian Government has built a pretty nice little interpretative walk through the area, and there is a place for visitors to camp (and, of course, buy things). Geologically, the Wadi Al-Hitan preserves an incredibly interesting series of lithofacies assemblages, recording the evolution of depositional environments in a fairly unique setting, providing us with an unprecedented view into the evolution of a major group of animals today. I'm pretty sure that's the Webster's Dictionary Definition of "Kick-ass".

So, in conclusion, the Wadi Al-Hitan belongs on everyone's "To See" list, especially if that list is a "Geology Places To See" compilation.

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