Packet 8: Bonus 7

Morgan and Wilson discovered two large “provinces” under the African and Pacific plates named for displaying this characteristic. For 10 points each:
[10m] What characteristic do seismic waves at “ultra zones” in the D'' (“D-double prime”) layer exhibit as they approach the core-mantle boundary?
ANSWER: low velocity [or low shear velocity or low friction velocity; accept equivalents such as reduced velocity or slow velocity or slowed down or slowing down; accept large low shear velocity provinces or LLSVPs]
[10e] LLSVPs may have formed along with mantle plumes, which underlie these regions of increased volcanism that are responsible for the Hawaiian islands forming.
ANSWER: hotspots
[10h] The prevailing theory of LLSVP formation is that they are accumulations of subducted ocean slabs, supported by a maximum isotopic ratio of this element and strontium called the DUPAL anomaly. Ocean island basalts are primarily classified with strontium, neodymium, and this element.
ANSWER: lead [or Pb]
<MS, Other Science (Earth Science)> | NAFTA-Packet-8

HeardPPBE %M %H %
3312.1297%24%0%

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