<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:x="urn:schemas-microsoft-com:office:excel" xmlns:dt="uuid:C2F41010-65B3-11d1-A29F-00AA00C14882" xmlns:b="urn:schemas-microsoft-com:office:publisher" xmlns:st1="urn:schemas-microsoft-com:office:smarttags" xmlns="http://www.w3.org/TR/REC-html40"> <head> <meta http-equiv=Content-Type content="text/html; charset=us-ascii"> <meta name=Generator content="Microsoft Word 11 (filtered medium)"> <o:SmartTagType namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="country-region"/> <o:SmartTagType namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="PostalCode"/> <o:SmartTagType namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="State"/> <o:SmartTagType namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="City"/> <o:SmartTagType namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="PlaceName"/> <o:SmartTagType namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="PlaceType"/> <o:SmartTagType namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="place"/> <o:SmartTagType namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="Street"/> <o:SmartTagType namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="address"/>  <style>  </style> </head> <body lang=EN-US link=blue vlink=purple> <div class=Section1> Hi All,<o:p></o:p> Here’s a report on research that may be of interest.<o:p></o:p> Bruce Richardson<o:p></o:p> Casper, Wyoming<o:p></o:p> <o:p> </o:p> <div> <div class=MsoNormal align=center style='text-align:center'> <hr size=2 width="100%" align=center tabindex=-1> </div> From: Jill Meredith Lovato Sent: Tuesday, April 12, 2005 7:05 AM To: uw-faculty@uwyo.edu; uwstaff-l@uwyo.edu Subject: UW-fac: Geologist to Talk on <st1:place w:st="on"><st1:PlaceName w:st="on">Yellowstone</st1:PlaceName> <st1:PlaceType w:st="on">Lake</st1:PlaceType></st1:place><o:p></o:p> </div> <o:p> </o:p> Spring 2005 Student-Faculty Forum on the Environment and Natural Resources<o:p></o:p> <o:p> </o:p> Sponsored by the <st1:place w:st="on"><st1:PlaceName w:st="on">Haub</st1:PlaceName> <st1:PlaceType w:st="on">School</st1:PlaceType></st1:place> and Ruckelshaus Institute of Environment and Natural Resources<o:p></o:p> <o:p> </o:p> <o:p> </o:p> “<st1:place w:st="on"><st1:PlaceName w:st="on">Yellowstone</st1:PlaceName> <st1:PlaceType w:st="on">Lake</st1:PlaceType></st1:place> Is Anything But Quiet:  <o:p></o:p> Volcanic and hydrothermal processes in a large lake above an active magma chamber”<o:p></o:p> <o:p> </o:p> Lisa Morgan<o:p></o:p> Geologist<o:p></o:p> <st1:place w:st="on"><st1:country-region w:st="on">U.S.</st1:country-region></st1:place> Geological Survey<o:p></o:p> <o:p> </o:p> Wednesday, April 13, 2005<o:p></o:p> 12:00 Noon<o:p></o:p> Union Family Room<o:p></o:p> <o:p> </o:p> <o:p> </o:p> Discoveries from recent (1999-2003) multi-beam sonar mapping and seismic-reflection surveys of Yellowstone Lake provide new insight into the recent geologic forces that have shaped a large lake at the active front of the Yellowstone hot spot, a region strongly affected by young (<2 my), large-volume (>100-1000’s km3) silicic volcanism, active tectonism, and accompanying uplift.  Specifically, our mapping has identified the extent of postcaldera collapse volcanism and active hydrothermal processes occurring above a large magma chamber on the lake floor.  Multiple advances and recessions of thick glacial ice have overlapped the volcanic and hydrothermal activity leaving a lake basin that has been shaped predominantly by fire and ice.  <st1:place w:st="on"><st1:PlaceName w:st="on">Yellowstone</st1:PlaceName> <st1:PlaceType w:st="on">Lake</st1:PlaceType></st1:place> has an irregular bottom covered with dozens of features directly related to hydrothermal, tectonic, volcanic, and sedimentary processes.  Detailed bathymetric, seismic reflection, and magnetic evidence reveals that rhyolitic lava flows underlie much of Yellowstone Lake and exert fundamental control on lake morphology and localization of hydrothermal activity in the northern, West Thumb, and central basins.  Many previously unknown features have been identified and include over 300 hydrothermal vents, several very large (>500 m diameter) hydrothermal explosion craters, many small hydrothermal vent craters (~1-200 m diameter), domed lacustrine sediments related to hydrothermal activity, elongate fissures cutting post-glacial sediments, siliceous hydrothermal spire structures, sublacustrine landslide deposits, submerged former shorelines, large glacial melting features, incipient faulting along the trace of the Eagle Bay fault zone, and a recently active graben.  Sampling and observations with a submersible remotely operated vehicle (ROV) confirm and extend our understanding of the identified features.  Faults, fissures, hydrothermally inflated domal structures, hydrothermal explosion craters, and sublacustrine landslides constitute potentially significant geologic hazards.  Fluids associated with active sublacustrine hydrothermal vent activity influence the geochemical composition of <st1:PlaceName w:st="on">Yellowstone</st1:PlaceName> <st1:PlaceType w:st="on">Lake</st1:PlaceType> water, which may significantly affect the <st1:place w:st="on">Yellowstone</st1:place> ecosystem.<o:p></o:p> <o:p> </o:p> <o:p> </o:p> <o:p> </o:p> <o:p> </o:p>  <o:p></o:p> Jill Lovato<o:p></o:p> Project Coordinator/Academic Advisor<o:p></o:p> Ruckelshaus Institute and the <st1:place w:st="on"><st1:PlaceName w:st="on">Haub</st1:PlaceName> <st1:PlaceType w:st="on">School</st1:PlaceType></st1:place><o:p></o:p> of Environment and Natural Resources<o:p></o:p> <st1:place w:st="on"><st1:PlaceType w:st="on">University</st1:PlaceType> of <st1:PlaceName w:st="on">Wyoming</st1:PlaceName></st1:place><o:p></o:p> <st1:address w:st="on"><st1:Street w:st="on">Dept.</st1:Street> 3971</st1:address><o:p></o:p> <st1:Street w:st="on"><st1:address w:st="on">1000 E. University Avenue</st1:address></st1:Street><o:p></o:p> <st1:place w:st="on"><st1:City w:st="on">Laramie</st1:City>, <st1:State w:st="on">WY</st1:State> <st1:PostalCode w:st="on">82071</st1:PostalCode></st1:place><o:p></o:p> Ph: 307.766.5146<o:p></o:p> <a href="http://www.uwyo.edu/enr/">www.uwyo.edu/enr/</a> <o:p></o:p> <o:p> </o:p> </div> </body> </html>