Wednesday, October 26, 2016

Whose Fault Was It Anyway?: The Endorheic Salton Sea and A "New" Salton Trough Fault

      A "new" fault was recently discovered parallel to the San Andreas Fault, near the Salton Sea, just south of Joshua Tree National Park, in the Colorado Desert of California.



       The Salton Sea was formed in 1905, when heavy rains caused the Colorado River to burst an Imperial Valley dike. It is now an important bird refuge.




     The newly-mapped Salton Trough Fault located in the   endorheic (or internally draining) Salton Sea could impact current seismic hazard models in the earthquake-prone region that includes the greater Los Angeles area. 




      These hazard models help protect lives and reduce property loss from earthquakes, says study lead author Dr. Valerie Sahakian.




      “To aid in accurately assessing seismic hazard and reducing risk in a tectonically active region,” she explains, “it is crucial to correctly identify and locate faults before earthquakes happen.”




     Researchers used a suite of instruments including multi-channel seismic data, ocean-bottom seismometers, and light detection and ranging (LIDAR) to map the deformation precisely within the various sediment layers in and around the bottom of the Salton Sea. The results reveal a strike-slip fault similar to the San Andreas Fault, with horizontal motion.





      While further research is needed to determine how the Salton Trough Fault interacts with the San Andreas Fault, residents in the area are understandably shaken up (pun intended). Other recent studies have revealed that the region has experienced significant earthquakes (magnitude about seven) roughly every 175 to 200 years for the last thousand years. A major rupture on the southern portion of the San Andreas Fault has not occurred in the last 300 years.





     “The extended nature of time since the most recent earthquake on the southern San Andreas has been puzzling to the earth sciences community,” says co-author Graham Kent. “Based on the deformation patterns, this new fault has accommodated some of the strain from the larger San Andreas system, so without having a record of past earthquakes from this new fault, it’s really difficult to determine whether this fault interacts with the southern San Andreas Fault at depth or in time.”


      “We need further studies to better determine the location and character of this fault, as well as the hazard posed by this structure,” confirms Sahakian. “The patterns of deformation beneath the sea suggest that the newly identified fault has been long-lived and it is important to understand its relationship to the other fault systems in this geologically complicated region.”

Whose fault is/was it anyway? If the engineers had not created the "faulty" Imperial Dikes which flooded the Colorado Desert of California creating the Salton Sea, would we have known about this fault much sooner?
Steph

33 comments:

  1. From Wikipedia: An endorheic basin (also endoreic basin) (from the Ancient Greek: ἔνδον, éndon, "within" and ῥεῖν, rheîn, "to flow") is a closed drainage basin that retains water and allows no outflow to other external bodies of water, such as rivers or oceans, but converges instead into lakes or swamps, permanent or seasonal, that equilibrate through evaporation. Such a basin may also be referred to as a closed or terminal basin or as an internal drainage system.

    And now we know from where Rhine River etymology derives!

    Going with the flow. . .

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    1. Yeah, that Greek "-rrhea" shows up everywhere in medicine and elsewhere in English: diarrhea, hemorrhage, menorrhea, and, my favorite, logorrhea.

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    2. Totally guessed wrong on logorrhea; I was thinking something closer to logarithm than to excessive talking.

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    3. Is 'drainage' scissors-paper-rock?

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  2. Steph, does this Salton Trough Fault pose any danger, or have implications for, the greater Denver area?

    Also, does any Greek or etymology scholar out there know if "rhein" ("to flow") and "rhin" ("nose") are etymologically related?

    LegoSaysThatAllHeKnowsIsThatWhenHeHasACodeHisNoseFlows

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    1. Lego, no I don't believe the STF poses a threat to the Denver area as it is so far from the Colorado desert in southeast California.

      As to rhein vs rhin,'snot possible?

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  3. Replies
    1. About halfway through Into the Inferno. Okay, not as good as Manohla Dargis thinks it is, not his best work. I think he's saying that people who live near or work on volcanoes are weird, but maybe it's just that people are weird. Not as good as Grizzle Man, Herzog's psychological docu-drama about a guy obsessed with bears (not to be confused with Project Grizzly, an even better non-Herzog psychological docu-drama-comedy about a guy obsessed with bears). Not nearly as much fun as Herzog's reading of Go the Fuck to Sleep.

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    2. That should be Grizzly Man, of course.

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    3. Herzog's rendering of the kid's book hit just the right tone of desperation.

      Will check out the bear docs.

      People are weird. Yes, they are.

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    4. Kid's book? I sure hope not!

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    5. Well, you know what I mean--for people with kids who want them to go the f@@@ to sleep!

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    6. Finished watching Into the Inferno. Disappointing. I know it's not a documentary about volcanoes per se, but how do you get through 107 minutes without even mentioning plate tectonics? Why does he suppose there are volcanoes in Iceland and Vanuatu, but not, say, New Jersey? And what was the Berkeley paleontologist in Ethiopia doing in the film? Mesmerizing cinematography of eruptions and lava flows, but I found the sound editing, e.g., the lack of delay between the sight and sound of an explosion miles away, jarring. I don't know, maybe it just wasn't what I was expecting, but I'm not a fan.

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    7. Sounds like 107 minutes I can miss. I certainly think a nod to plate tectonics ought to be there.

      Maybe Jersey needs a volcano or two?

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  4. What do y'all make of the latest Hillary Clinton e-mail kerfuffle?

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    1. No idea. But every time I think we've heard the last of Anthony Weiner, there he is again. People are weird. Yes, they are.

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    2. People are Weird. Yes, They Are -- title of the newest "kid's book?"

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  5. Replies
    1. I guess it's not the wurst you could call them, but how would you like it if someone referred to your remains that way? Don't be a brat.

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    2. Touché! What a grind!

      Dinosaurs are weird. Yes, they are. (But, not as weird as people. . .)

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    3. Now you're just hotdogging.

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    4. So, we're back to Hillary's emails, are we?

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    5. It's all the media is talking and writing about. It is the wurst, for sure.

      Hoping "Move along, nothing to see here" will become appropriate very soon.

      Ah, give me a dinosaur sausage brain any day, Patty!

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  6. 65 million years young : The entire group in dino costumes would have been even better!

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  7. H🎃A👻P🎃P👻Y🎃👻H🎃A👻L🎃L👻O🎃W👻E🎃E👻N!

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  8. New post on "Popeye's Spinach Was Never Like This: The Superfood Is Also An Explosives Detector!" is now up.

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