I highly recommend the book "Meteorites, Ice, and Antarctica - A personal account" by William A. Cassidy.
It goes into all sorts of technical stuff and the whole history and difficulty of the operations but is also a corking good read. My personal favourite anecdote involves 2 grad students and the punchline "Who is it?". Anyone whom has read the book will likely already be deep belly chuckling to themselves. Rob McC --- On Fri, 7/25/08, Ruben Garcia <[EMAIL PROTECTED]> wrote: > From: Ruben Garcia <[EMAIL PROTECTED]> > Subject: Re: [meteorite-list] A question about Antarctica vs Alaska meteorite > hunting. > To: [email protected], "Mr EMan" <[EMAIL PROTECTED]> > Date: Friday, July 25, 2008, 1:53 AM > Great information, Thanks! > > Ruben Garcia > Phoenix, Arizona > http://www.mr-meteorite.com > http://www.youtube.com/profile_videos?user=meteorfright&p=v > > > --- On Thu, 7/24/08, Mr EMan <[EMAIL PROTECTED]> > wrote: > > > From: Mr EMan <[EMAIL PROTECTED]> > > Subject: Re: [meteorite-list] A question about > Antarctica vs Alaska meteorite hunting. > > To: [email protected], > [EMAIL PROTECTED] > > Date: Thursday, July 24, 2008, 4:24 PM > > Hello Ruben Good question. > > > > What makes the recovery in Antarctica is a combination > of > > rare processes and not just glaciers catching up > > meteorites. It takes a rare combination of > bedrock, ice > > and wind to expose the meteorite fields in Antarctica. > > > > Meteorites falling into the main flow are likely lost > > forever. But if it falls along the edge of the field > in a > > side lobe-- not in the main glacial flow--there is a > chance > > it can be exposed again. Sometimes thousands of > years > > later. The ice in the top portion of the lobe > doesn't > > scour the bedrock and stir up rock fragments like the > main > > flow does and has minimal inclusions of earth rock in > the > > load carried by the ice. A lobe occurs near a > bottleneck > > and is like a slow motion wave getting sloshed out of > a bath > > tub-- being pushed out of the "tub" itself > by the > > main flow and rising bedrock. When the lobe hits the > > valley rim-- a gentle slope or buried ridge-line, the > ice > > is forced up and over it, exposing the ice to very > high > > velocity and extremely dry winds. This action scours > away > > the ice matrix --perhaps even sublimates some ice > directly > > into water vapor. In any event, the ice is removed > by > > wind action leaving the meteorites concentrated on > > the surface. "Concentrated" implies a > placer > > deposit but in fact means that in fives and tens > meteorites > > are exposed each season before the ice flows over the > slope > > and they are reburied in ice unless recovered by the > annual > > meteorite search teams. > > > > I believe that a few iron meteorites have been > recovered in > > glacial moraines elsewhere but that is a different > > concentration mechanism and they certainly aren't > > separated out from the earth rock!. Active glaciers > such > > as associated with caving icebergs carry whatever load > they > > have inside them into the sea. > > > > Meteorites don't seem to survive long in moist > frequent > > freeze thaw environments making finding stone > meteorites > > remote. I don't know the circumstances of recent > > Canadian meteorites and couldn't say if they were > > related to glaciers. The environment in glacial > fields is > > against stones but favors irons, IMHO, so long as the > ice > > doesn't make icebergs but ends in annual moraine > > building piles of debris. > > > > Elton > > > > --- On Thu, 7/24/08, Ruben Garcia > > <[EMAIL PROTECTED]> wrote: > > Hi all, > > I know that many of you follow the work done in > Antarctica > > a lot more closely > > than I do. I know that meteorites have been recovered > there > > for over two > > decades and more recently in eastern Manitoba, Canada. > All > > due to ancient > > glaciers and their movements. My questions are as > follows: > > > > 1)Has anyone really searched for meteorites in other > > glacial areas such as > > Alaska? > > > > 2)Is there any reason to believe that meteorites > > wouldn't be found there? > > 3)Are the Alaskan glaciers old enough to sufficiently > > "catch"meteorites? > > > > ______________________________________________ > http://www.meteoritecentral.com > Meteorite-list mailing list > [email protected] > http://six.pairlist.net/mailman/listinfo/meteorite-list ______________________________________________ http://www.meteoritecentral.com Meteorite-list mailing list [email protected] http://six.pairlist.net/mailman/listinfo/meteorite-list
