<?xml version='1.0' encoding='utf-8'?>
<oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
  <dc:contributor>K. Seats</dc:contributor>
  <dc:contributor>H. Benz</dc:contributor>
  <dc:creator>K.D. Koper</dc:creator>
  <dc:date>2010</dc:date>
  <dc:description>In the classic microseismic band of 5-20 sec, seismic noise consists mainly of fundamental mode Rayleigh and Love waves; however, at shorter periods seismic noise also contains a significant amount of body-wave energy and higher mode surface waves. In this study we perform a global survey of Earth's short-period seismic noise field with the goal of quantifying the relative contributions of these propagation modes. We examined a year's worth of vertical component data from 18 seismic arrays of the International Monitoring System that were sited in a variety of geologic environments. The apertures of the arrays varied from 2 to 28 km, constraining the periods we analyzed to 0.25-2.5 sec. Using frequency-wavenumber analysis we identified the apparent velocity for each sample of noise and classified its mode of propagation. The dominant component was found to be L&lt;sub&gt;g&lt;/sub&gt;, occurring in about 50% of the noise windows. Because L&lt;sub&gt;g&lt;/sub&gt; does not propagate across ocean-continent boundaries, this energy is most likely created in shallow water areas near coastlines. The next most common component was P-wave energy, which accounted for about 28% of the noise windows. These were split between regional P waves (P&lt;sub&gt;n&lt;/sub&gt;=P&lt;sub&gt;g&lt;/sub&gt; at 6%), mantle bottoming P waves (14%), and core-sensitive waves (PKP at 8%). This energy is mostly generated in deep water away from coastlines, with a region of the North Pacific centered at 165?? W and 40?? N being especially prolific. The remainder of the energy arriving in the noise consisted of R&lt;sub&gt;g&lt;/sub&gt; waves (28%), a large fraction of which may have a cultural origin. Hence, in contrast to the classic micro-seismic band of 5-20 sec, at shorter periods fundamental mode Rayleigh waves are the least significant component.</dc:description>
  <dc:format>application/pdf</dc:format>
  <dc:identifier>10.1785/0120090120</dc:identifier>
  <dc:language>en</dc:language>
  <dc:title>On the composition of earth's short-period seismic noise field</dc:title>
  <dc:type>article</dc:type>
</oai_dc:dc>