[meteorite-list] Dry Lake Stewnfields??
From: meteoriteshow <meteoriteshow_at_meteoritecentral.com>
Date: Thu Apr 22 10:17:48 2004 Message-ID: <006c01c3c3b3$4a0af420$9bc5933e_at_monordinateur> C'est un message de format MIME en plusieurs parties. ------=_NextPart_000_0069_01C3C3BB.AB73CEA0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Hi Doug and List, I also wonder about another point on meteorite falls... Since I started = hunting them, I thought that they can fall anywhere, the location of = their landing place depending on their orbit around the sun and the = angle they meet the Earth with. Is that right or are there any areas on = our planet where they get more "attracted" ? There have been more finds in Antarctic than anywhere else, but I guess = that it's simply because people have been searching for them there for a = longer time, but can it be for another reason ? Has the magnetic field = linking the poles any effect (like for boreal auroras) ? ... I'm not a scientist and maybe my question sounds strange, but should = anybody have a clear and easy to understand explanation, thanks in = advance for sending it, just for my knowledge. Kind regards Frederic Beroud www.meteoriteshow.com IMCA #2491 ----- Original Message -----=20 From: MexicoDoug_at_aol.com=20 To: j.divelbiss_at_att.net=20 Cc: meteorite-list_at_meteoritecentral.com=20 Sent: Tuesday, December 16, 2003 5:49 AM Subject: Re: [meteorite-list] Dry Lake Stewnfields?? Hi John, I think if we get back to basic definitions, a strewn field = is an ellipsoid shape caused by a mid air explosion raining down = material, as far as I understand. What happens afterwards to the = material is irrelevant. And the strewn field is a geometric = representation fitted to the fall in practice, not the actual individual = stones. If some gets moved, picked clean, the boundaries of the strewn = field can't change, from their original definition. Perhaps some of the hunters among us will not see it that way...as = strewn tends to bring a connotation of waltzing in and cleaning up. And = an empty strewn field sounds odd... So I would think that the technical "set one straight answer" you want = is that: Mathematically it takes at least four border points to make an = ellipse, but to actually be able to fit one with any confidence in an = area, you need plenty more, to fill in the area. A neat statistical = definition seems impractical, so it will come down top the field = researcher's opinion. If the one who did the research wants to call it = a strewn field and their is evidence for a mid air explosion...then we = should have one. And if there are a few rocks...in the desert, or in = Chicago, and the principal investigator(s) don't feel there is enough = for an ellipse, then its not, because they say so. An it is a good = assumption if we happen upon an old scattered field, we can say...this = might be a strewn field, but lacking a good cause-effect ellipse = explanation there can't be a right answer for lack of data. In the end = one can probably collect opinions on this until blue in the face...and = who calls what a what...but for what? Strewn fields are simply human categories so we can make sense out of = natural events that don't have to conform to our neat, ways of = nomenclature. Just like the concept of a species or a race in biology. = You know an obvious one when you see it...but when you start taking it = as gospel and look at the limits of the definition, the whole think = breaks down, and mass consensus isn't reached...plus air resistance = already distorts a strewn field to a researcher. So there has got to be = a little eyeballing going on since tiny particles don't fall nicely. If = it looks like a strewn field, (tastes like one), ... Sipping my hot chocolate...Saludos Doug Dawn Mexico En un mensaje con fecha 12/15/2003 10:17:15 PM Mexico Standard Time, = j.divelbiss_at_att.net escribe: To Rob, Bob, Adam, and others: Recent finds from the Nevada dry lakes were grouped in a small area = within a=20 dry lake. The finding of three apparent pieces from same fall = created a=20 description by Adam that these finds might constitute a new = strewnfield.=20 Questions/observations in regards to desert strewnfields. 1. Obvious groupings of fallen masses would make the likelihood of = the area=20 being a meteorite stewnfield. Do multiple finds in desert locale = usually get=20 described as a stewnfield? 2. Does the fact that many rocks get moved around in these = environments take=20 the strewnfield idea down a notch with rocks being scattered?...or = does their=20 proximity within the bounds of normal surface movements qualify them = to be=20 still within the original strewnfield?=20 3. Is the idea of stating a location has a new strewnfield more = about this=20 location being a new place to find more than one meteorite of the = same=20 apparent fall?...and not so much about the actual fall = characteristics? I guess I'm just curious about the use of word strewnfield in this = case? Yearning to be set straight, John ------=_NextPart_000_0069_01C3C3BB.AB73CEA0 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 5.50.4134.600" name=3DGENERATOR> <STYLE></STYLE> </HEAD> <BODY bgColor=3D#ffffff> <DIV><FONT face=3DArial size=3D2>Hi Doug and List,</FONT></DIV> <DIV><FONT face=3DArial size=3D2></FONT> </DIV> <DIV><FONT face=3DArial size=3D2>I also wonder about another = point on meteorite=20 falls... Since I started hunting them, I thought that they can fall = anywhere,=20 the location of their landing place depending on their orbit around the = sun and=20 the angle they meet the Earth with. Is that right or are there any areas = on our=20 planet where they get more "attracted" ?</FONT></DIV> <DIV><FONT face=3DArial size=3D2>There have been more finds in Antarctic = than=20 anywhere else, but I guess that it's simply because people have been = searching=20 for them there for a longer time, but can it be for another reason ? Has = the=20 magnetic field linking the poles any effect (like for boreal auroras) ?=20 ...</FONT></DIV> <DIV><FONT face=3DArial size=3D2>I'm not a scientist and maybe my = question sounds=20 strange, but should anybody have a clear and easy to understand = explanation,=20 thanks in advance for sending it, just for my = knowledge.</FONT></DIV> <DIV><FONT face=3DArial size=3D2>Kind regards</FONT></DIV> <DIV><FONT face=3DArial size=3D2></FONT> </DIV> <DIV><FONT face=3DArial size=3D2>Frederic Beroud<BR><A=20 href=3D"http://www.meteoriteshow.com">www.meteoriteshow.com</A><BR>IMCA=20 #2491</FONT></DIV> <BLOCKQUOTE=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=3DMexicoDoug_at_aol.com=20 href=3D"mailto:MexicoDoug_at_aol.com">MexicoDoug@aol.com</A> </DIV> <DIV style=3D"FONT: 10pt arial"><B>To:</B> <A = title=3Dj.divelbiss_at_att.net=20 href=3D"mailto:j.divelbiss_at_att.net">j.divelbiss@att.net</A> </DIV> <DIV style=3D"FONT: 10pt arial"><B>Cc:</B> <A=20 title=3Dmeteorite-list_at_meteoritecentral.com=20 = href=3D"mailto:meteorite-list_at_meteoritecentral.com">meteorite-list@meteor= itecentral.com</A>=20 </DIV> <DIV style=3D"FONT: 10pt arial"><B>Sent:</B> Tuesday, December 16, = 2003 5:49=20 AM</DIV> <DIV style=3D"FONT: 10pt arial"><B>Subject:</B> Re: [meteorite-list] = Dry Lake=20 Stewnfields??</DIV> <DIV><BR></DIV><FONT face=3Darial,helvetica><FONT lang=3D0 = face=3DArial size=3D2=20 FAMILY=3D"SANSSERIF" PTSIZE=3D"10">Hi John, I think if we get back to = basic=20 definitions, a strewn field is an ellipsoid shape caused by a mid air=20 explosion raining down material, as far as I understand. What = happens=20 afterwards to the material is irrelevant. And the strewn field = is a=20 geometric representation fitted to the fall in practice, not the = actual=20 individual stones. If some gets moved, picked clean, the = boundaries of=20 the strewn field can't change, from their original = definition.<BR><BR>Perhaps=20 some of the hunters among us will not see it that way...as strewn = tends to=20 bring a connotation of waltzing in and cleaning up. And an empty = strewn=20 field sounds odd...<BR><BR>So I would think that the technical "set = one=20 straight answer" you want is that: Mathematically it takes at = least four=20 border points to make an ellipse, but to actually be able to fit one = with any=20 confidence in an area, you need plenty more, to fill in the = area. A neat=20 statistical definition seems impractical, so it will come down top the = field=20 researcher's opinion. If the one who did the research wants to = call it a=20 strewn field and their is evidence for a mid air explosion...then we = should=20 have one. And if there are a few rocks...in the desert, or in = Chicago,=20 and the principal investigator(s) don't feel there is enough for an = ellipse,=20 then its not, because they say so. An it is a good assumption if = we=20 happen upon an old scattered field, we can say...this might be a = strewn field,=20 but lacking a good cause-effect ellipse explanation there can't be a = right=20 answer for lack of data. In the end one can probably collect = opinions on=20 this until blue in the face...and who calls what a what...but for=20 what?<BR><BR>Strewn fields are simply human categories so we can make = sense=20 out of natural events that don't have to conform to our neat, ways of=20 nomenclature. Just like the concept of a species or a race in=20 biology. You know an obvious one when you see it...but when you = start=20 taking it as gospel and look at the limits of the definition, the = whole think=20 breaks down, and mass consensus isn't reached...plus air resistance = already=20 distorts a strewn field to a researcher. So there has got to be = a little=20 eyeballing going on since tiny particles don't fall nicely. If = it looks=20 like a strewn field, (tastes like one), ...<BR><BR>Sipping my hot=20 chocolate...Saludos<BR>Doug Dawn<BR>Mexico<BR><BR>En un mensaje con = fecha=20 12/15/2003 10:17:15 PM Mexico Standard Time, j.divelbiss_at_att.net=20 escribe:<BR><BR> <BLOCKQUOTE=20 style=3D"PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #0000ff 2px = solid; MARGIN-RIGHT: 0px"=20 TYPE=3D"CITE"><BR><BR>To Rob, Bob, Adam, and others:<BR><BR>Recent = finds from=20 the Nevada dry lakes were grouped in a small area within a <BR>dry = lake. The=20 finding of three apparent pieces from same fall created a = <BR>description by=20 Adam that these finds might constitute a new strewnfield.=20 <BR><BR>Questions/observations in regards to desert = strewnfields.<BR><BR>1.=20 Obvious groupings of fallen masses would make the likelihood of the = area=20 <BR>being a meteorite stewnfield. Do multiple finds in desert locale = usually=20 get <BR>described as a stewnfield?<BR><BR>2. Does the fact that many = rocks=20 get moved around in these environments take <BR>the strewnfield idea = down a=20 notch with rocks being scattered?...or does their <BR>proximity = within the=20 bounds of normal surface movements qualify them to be <BR>still = within the=20 original strewnfield? <BR><BR>3. Is the idea of stating a location = has a new=20 strewnfield more about this <BR>location being a new place to find = more than=20 one meteorite of the same <BR>apparent fall?...and not so much about = the=20 actual fall characteristics?<BR><BR>I guess I'm just curious about = the use=20 of word strewnfield in this case?<BR><BR>Yearning to be set=20 = straight,<BR><BR>John<BR><BR><BR></BLOCKQUOTE><BR><BR></BLOCKQUOTE></FONT= ></FONT></BODY></HTML> ------=_NextPart_000_0069_01C3C3BB.AB73CEA0-- Received on Tue 16 Dec 2003 04:02:09 AM PST |
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