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Researchers Discover Ancient Massive Landslide
sciencehabit writes For decades, geologists have noted the signs of ancient landslides in southwestern Utah. Although many parts of the landscape don't look that odd at first glance, certain layers include jumbled masses of fractured rock sandwiched among thick veins of lava, ash, and mud. Now, new fieldwork suggests that many of those ancient debris flows are the result of one of Earth's largest known landslides, which covered an area nearly 39 times the size of Manhattan.
Anybody know what "39 times the size of Manhattan" is in football fields?
The past is the key to the present. This is the kind of analysis that points to current and future risks. Rock, weathered rock and soil are relatively static on the scale of our lifetime or memory, but are dynamic on geologic timescales. 20-30 Million years ago (Miocene - Oligocene) is less than half of the time back to the dinosaurs. Lots of things have happened since the dinosaurs flew away and many of them are hidden beneath newer rock and weathering products. Tying all the small pieces (landslides) together into one event is a great piece of detective work. Well Done.
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there isn't another landslide into Beaver, if you know what I mean.
I guess they didn't rig election back then, they way they do now.
Landslide cocktail recipe
Lots of things have happened since the dinosaurs flew away
I love that formulation.
(And just coined a related one: "... since the dinosaurs gave us the bird" B-) )
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
It doesn't look a day over 18,000,000, 18,250,001 old. Tops.
How long ago is that is dog years?
Oh, while I'm at it, speaking of quasi-quantity based analogies that humans can only think about in terms of 'that's a lot,' (my point is is that can we really think of the difference between 100,000 or 100,000,000? How many peanuts can fit in a shipping container? Inside the Statue of Liberty?), where was I? Oh, is we lined up everyone who ever made such an analogy it would be 812 to the 12th power longer than the line at Comicon.
Google usually converts anything, so I tried:
39 manhattans in km2
but this time, even Google couldn't convert it. You Americans really need to start using metric instead of measuring stuff in manhattans.
Many years ago I took a geomorphology class in college. Geomorphology is the study of the landscape and the geologic processes that shape the contours of the land. We had a lab where we identified landslides using aerial photos and a stereoscope. I already had some experience looking through a stereoscope and identifying landslides so I was finding lots of them. The professor walked by and noticed. He said "OK Robert, now look for larger landslides." They were harder to see because they were older. But they could be identified by their surface mottling and shape. So I start to see them and there are lots of them. The professor was impressed and he said "OK, now step back and look at the entire hill side." When I did this I realized that the entire hillside was one massive landslide. Ridge to valley bottom. Probably on the order of a square mile. He suggested that at some time in the past the entire hillside slid. Probably the result of a 1906 type earthquake in the middle of a very wet winter when all the soil on the hillside was saturated with water. It blew my mind.
RLH