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Kodachrome State Park UT

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What's New?

Moonrise over sandstone pipe and Jurassic Entrada Sandstone, Kodachrome State Park, Utah

Recent Research

The intrusive-extrusive connection in the Turkey Creek caldera, SE Arizona.

Deering, C. D. et al (2016), Zircon record of the plutonic-volcanic connection and protracted rhyolite melt evolution.  Geology 44, 267-270.  doi:10.1130/G37539.1

Statistical analysis of speciation among dinosaurs
shows most were in decline tens of millions of years before the Cretaceous–Paleogene mass extinction event 66 Mya

Sakamoto, M., Bentonb, M. J., and Vendittia, C. (2016), Dinosaurs in decline tens of millions of years before their final extinctionPNAS 113, 5036–5040.  doi:10.1073/pnas.1521478113

New apatite ages from the Rio Grande rift suggest a geodynamic model for extension.

Zircons paint a messy picture of the suture in Grand Canyon's Crystal shear zone.

Holland, M. E. et al (2015), An imbricate midcrustal suture zone: The Mojave-Yavapai Province boundary in Grand Canyon, ArizonaGSA Bulletin 127, 1391-1410.  doi:10.1130/B31232.1

Seismicity in the interior western U.S. occurs along an intermountain belt
that coincides with a
change from thin to thick lithosphere.  Models suggest active mantle flow may be one of the reasons.

Becker, T. W. et al (2015), Western US intermountain seismicity caused by changes in upper mantle flowNature 524, 458-461. doi:10.1038/nature14867

Are more felsic magmas the result
of fractionation or assimilation?  Are granites what's left after more mantle-like components crystallize and sink or are they formed by the addition of crustal country rock as the melt ascends?  Recent papers suggest
fractionation may be the dominant process.
Kemner, F., Haase, K. M., Beier, C., Krumm, S. and Brandl, P. A. (2015), Formation of andesite melts and Ca-rich plagioclase in the submarine Monowai Volcanic System, Kermadec Arc. Geochem. Geophys. Geosyst. Accepted Author Manuscript. doi:10.1002/2015GC005884


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Copyright R Scott Cherba All Rights Reserved
Updated 18 February 2018