[meteorite-list] Aswan Rock - Opinions?
From: N Lehrman <nlehrman_at_meteoritecentral.com>
Date: Thu Apr 22 10:17:45 2004 Message-ID: <00bf01c3c0c8$a6477940$dea4fea9_at_homeportal.2wire.net> This is a multi-part message in MIME format. ------=_NextPart_000_00BC_01C3C085.96A22D20 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Jeff & list, I've spent my career with rocks like that! It is a hydrothermal breccia = from a low-sulfidation epithermal vein system. You'll notice that some = of the clasts have quartz/chalcedony hairlines healing jigsaw-puzzle = breccias (pieces would still fit neatly back together, not jumbled or = significantly displaced). This is hydraulic fracturing that forms as = fluid pressures exceed lithostatic pressures, just before a hydrothermal = explosion. Once the system cracks and explodes, fluid streaming does = jumble and rotate most of the clasts. Your rock likely contains = anomalous amounts of As, Hg, Sb, and quite possibly, Au and Ag. The = rounded exterior is simply from erosion and water transport. From the = photos I can't tell for sure what the clasts are, but I would guess they = are rhyolite (a common associate of this style of mineralization). =20 Merry Winter Solstice and a Happy New Orbit to All, Norm Lehrman (http://TektiteSource.com)=20 ----- Original Message -----=20 From: Jeff Kuyken=20 To: Meteorite List=20 Sent: Friday, December 12, 2003 2:38 AM Subject: [meteorite-list] Aswan Rock - Opinions? Hey all, When I was in Egypt in October, I jumped onto a young half-trained = CCRRAAZZYY camel and headed out into the desert. Among a few rocks = (mostly fossils) I found an interesting stone which was nothing like the = others in the area. I don't think it is a meteorite but it does look = like some kind of breccia. It is a broken quarter sphere in shape and = the photos are of the two broken surfaces. I'd appreciate any opinions = on this one. The links are: http://www.meteoritesaustralia.com/images/Aswan 1.jpg http://www.meteoritesaustralia.com/images/Aswan 2.jpg Cheers, Jeff Kuyken I.M.C.A. #3085 www.meteorites.com.au ------=_NextPart_000_00BC_01C3C085.96A22D20 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META http-equiv=3DContent-Type content=3D"text/html; = charset=3Diso-8859-1"> <META content=3D"MSHTML 6.00.2800.1264" name=3DGENERATOR> <STYLE></STYLE> </HEAD> <BODY bgColor=3D#ffffff> <DIV><FONT size=3D2>Jeff & list,</FONT></DIV> <DIV><FONT size=3D2></FONT> </DIV> <DIV><FONT size=3D2> <DIV><FONT size=3D2>I've spent my career with rocks like that! It = is a=20 hydrothermal breccia from a low-sulfidation epithermal vein = system. You'll=20 notice that some of the clasts have quartz/chalcedony hairlines healing=20 jigsaw-puzzle breccias (pieces would still fit neatly back together, not = jumbled=20 or significantly displaced). This is hydraulic fracturing that = forms as=20 fluid pressures exceed lithostatic pressures, just before a hydrothermal = explosion. Once the system cracks and explodes, fluid streaming = does=20 jumble and rotate most of the clasts. Your rock likely contains = anomalous=20 amounts of As, Hg, Sb, and quite possibly, Au and Ag. The rounded = exterior=20 is simply from erosion and water transport. From the photos I = can't tell=20 for sure what the clasts are, but I would guess they are rhyolite (a = common=20 associate of this style of mineralization). </FONT></DIV> <DIV> </DIV> <DIV>Merry Winter Solstice and a Happy New Orbit to All,</DIV> <DIV> </DIV> <DIV>Norm Lehrman</DIV> <DIV>(<A href=3D"http://TektiteSource.com">http://TektiteSource.com</A>) = </DIV> <DIV> </DIV> <DIV> </DIV></FONT></DIV> <BLOCKQUOTE dir=3Dltr=20 style=3D"PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; = BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px"> <DIV style=3D"FONT: 10pt arial">----- Original Message ----- </DIV> <DIV=20 style=3D"BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: = black"><B>From:</B>=20 <A title=3Djeff_at_meteoritesaustralia.com=20 href=3D"mailto:jeff_at_meteoritesaustralia.com">Jeff Kuyken</A> </DIV> <DIV style=3D"FONT: 10pt arial"><B>To:</B> <A=20 title=3Dmeteorite-list_at_meteoritecentral.com=20 href=3D"mailto:meteorite-list_at_meteoritecentral.com">Meteorite List</A> = </DIV> <DIV style=3D"FONT: 10pt arial"><B>Sent:</B> Friday, December 12, 2003 = 2:38=20 AM</DIV> <DIV style=3D"FONT: 10pt arial"><B>Subject:</B> [meteorite-list] Aswan = Rock -=20 Opinions?</DIV> <DIV><BR></DIV> <DIV><FONT size=3D2>Hey all,</FONT></DIV> <DIV><FONT size=3D2></FONT> </DIV> <DIV><FONT size=3D2>When I was in Egypt in October, I jumped onto a = young=20 half-trained CCRRAAZZYY camel and headed out into the desert. Among a = few=20 rocks (mostly fossils) I found an interesting stone which was nothing = like the=20 others in the area. I don't think it is a meteorite but it does look = like some=20 kind of breccia. It is a broken quarter sphere in shape and the photos = are=20 of the two broken surfaces. I'd appreciate any opinions on this = one.=20 The links are:</FONT></DIV> <DIV><FONT size=3D2></FONT> </DIV> <DIV><FONT size=3D2><A=20 href=3D"http://www.meteoritesaustralia.com/images/Aswan = 1.jpg">http://www.meteoritesaustralia.com/images/Aswan=20 1.jpg</A></FONT></DIV> <DIV><FONT size=3D2></FONT> </DIV> <DIV><FONT size=3D2><A=20 href=3D"http://www.meteoritesaustralia.com/images/Aswan = 2.jpg">http://www.meteoritesaustralia.com/images/Aswan=20 2.jpg</A></FONT></DIV> <DIV><FONT size=3D2></FONT> </DIV> <DIV><FONT size=3D2>Cheers,</FONT></DIV> <DIV><FONT size=3D2></FONT> </DIV> <DIV><FONT size=3D2>Jeff Kuyken<BR>I.M.C.A. #3085<BR><A=20 = href=3D"http://www.meteorites.com.au">www.meteorites.com.au</A></FONT></D= IV></BLOCKQUOTE></BODY></HTML> ------=_NextPart_000_00BC_01C3C085.96A22D20-- Received on Fri 12 Dec 2003 10:57:28 AM PST |
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