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In article <51256a$9i7@nntp.Stanford.EDU>, karish@gondwana.Stanford.EDU
(Chuck Karish) wrote:
 on some continental plates while eroding others.
> 
> To get back to the original question, there is no well-accepted
> answer.  The "slab pull" phenomenon that Tom Williams described
> is merely a way to describe the observation that those
> current-day plates that have large proportions of their margins
> being subducted are the ones that move most rapidly.  This
> doesn't mean that the plates are in tension, being pulled from
> their margins.  Plates are much too weak to transmit enough
> force across an entire plate to move the plate, either in
> tension or in compression.
OK Chuck, I'll bite.:)
(By the way, I did expect to take some flack for posting a much
too simplistic answer.)
I'll be your straw dog:
Why are the plates too weak?  How can this possibly be?
I'm not a geophysicist although I impersonate one
from time to time as a T.A.
Your point made me curious:
If the plates were really that weak, why would we have 'plates'
_at all_. I mean if they are truly to weak to support tension,
then why would these really big chunks of rock move as relatively 
rigid bodies with _comparatively_ little intraplate deformation.
No matter how you slice it, most of the relative motion, and the
strain, is accomplished at the margin of the plate.
Even if you put your trust in theoretical models:
From yield stress envelope calculations of the sort
that I'm familiar with, the total strength of the lithosphere
is  10^13 to 3x10^13 N/m. (Sorry my class notes don't have references).
Estimates of the average stress imparted over the thickness
of the lithosphere as a result of plate interactions: 20-30MPa
(Bott and Kusznir, 1984  Tectonophysics: 1-13).
Over a 125 km thick lithosphere, this corresponds to an average
stress level of 2.5x10^12 to 3.75x10^12 N/m.
Therefore, the strength of the typical lithosphere is able
to withstand 3 to 10 times the force imparted per meter of
plate margin, unless you concentrate the stress.
I'm sure that my understanding of such considerations is
a little out of date, I'm a stratigrapher after all,
but how could the plates be 'much too weak' to 
be pulled from their margins?
Tom
-- 
Tom Williams             williams@pangea.stanford.edu
Basin Analysis, Sequence Stratigraphy
Stanford Program on Deep-Sea Depositional Systems
http://pangea.stanford.edu/~williams/williams.html

In article <5178iu$eoc@nw101.infi.net>, tomitire@vegas.infi.net says...
->I still maintain that the program fails because the programmers 
->cannot reach their desired goal and do not have the path for 
->success within their abilities.
	Maybe. Mayby its due at least as much to the fact that they built a 
kind of striped down machine with only five parralles processors so they 
could keep a reasonable budget.
	The program, as I understand it is capable of running on a much more 
powerful machine.
	Unfortunately, or perhaps fortunately depending on your point of 
view, the company can't spare any of the really poweful (20 processor if I 
remember right) machines for  publicitiy stunts.
	Ciao. 
-- 
	Michael Fisher, ET1/SS USN ret., lawstudent	
        http://www.sonoma.edu/cthink/Library/intraits.html
	*		*		*     
     He that would make his own liberty secure, 
     must guard even his enemy from oppression; 
     for if he violates this duty, 
     he establishes a precedent that will reach to himself.
                                             Thomas Paine

In article <3236142D.758E@navix.net>,
Robert D. Brown  wrote:
>My contention is that Hawaii (the primary volcanic site) was created by
>a very large impact occurring at this site, and that the mountains
>named above represent the impact crater's rim.
How do you explain the undisturbed ocean floor sediments of the
Pacific basin, some of which are much older than 65 My and are
well dated by micropaleontological technmiques, correlated
with paleomagnetic logs?  Or, for that matter, the Cretaceous
corals that have been recovered from the Emperor seamounts?
>If one's position is: impacts don't occur on Earth, then none of the
>above makes any sense at all.
Whose position is that?  No competent earth scientist that I
know or know of.
I know any number of people who will consider that Mr. Brown's
position makes no sense at all, as long as he chooses to
ignore geologic data that contradicts his theories.
>What did the old guard (whose regular theme is to argue against all
>catastrophist interpretations of Earth history, e.g. taking a
>consistent position in a religious, not scientific debate) have say in
>response to this:  "Good thing we have Jupiter out there to prevent big
>impactors from coming our way".
I won't hold my breath waiting for an answer from them.  There
is no such old guard.
The inverse square law for gravitational interactions keeps
even a mass as large as Jupiter from being an efficient sweep
for objects that come from outside the orbital plane of the
Solar System.
--
    Chuck Karish          karish@mindcraft.com
    (415) 323-9000 x117   karish@pangea.stanford.edu

References:  <50skhp$41u@amenti.rutgers.edu>  <50vga2$ck5@niflheim.rutgers.edu>  <512432$jou@niflheim.rutgers.edu>  <512vfq$rdq@niflheim.rutgers.edu>
Organization: OMS Development
Distribution: inet
Michael Huemer (owl@niflheim.rutgers.edu) wrote:
: meron@cars3.uchicago.edu writes:
: >No, it would've a counter survival value.  It would either generate 
: >overcrowding (in which case death would come from starvation, aging 
: >not being an issue) or, assuming it would be accompanied by a greatly 
: Perhaps, but that doesn't mean it wouldn't be an advantage to the
: individuals who had the gene.  Have you heard of 'the tragedy of the
: commons'?
: If you had 12 kids (and successfully raised them to adulthood), more
: copies of your genes would reproduce, so in that sense your genes
: would have an 'advantage,' i.e., they would be more likely dominate
: the future population.  The fact that by doing this, you may be
: screwing up the world for everyone in the future makes no difference.
: Evolution, so to speak, is blind to that.
False.  Evolution operates at the level of entire populations as well as 
individuals.  Anything that enhances the survival of a particular 
population will enhance the survival of all the individual genes included 
in that population.  Natural selection isn't a zero-sum game in which one 
individual's genes try to "dominate" another's (despite that fact that 
popularizations make it sound that way, but that's really a projection of 
Anglo-American ideals about the role of the individual in society onto 
biological processes).  If a population dies out due to overcrowding, the 
"strongest" individual genes in that population have been selected out 
just as much as the "weakest" genes.
Genes that grant an individual and his progeny an 'advantage" but screw 
up the future world for everyone simply don't survive.  Period.  Every 
time they arise, they'll be selected out; the fact that they cause other 
genes in other people to be selected out as well doesn't matter.  One 
person's loss is not automatically another person's gain.

On 1996-09-09 fdever said:
   >millerc@cs.man.ac.uk (Crispin Miller) wrote:
   >>tomitire@vegas.infi.net wrote:
   >>: On 1996-09-01 lefty said:
   >Intelligence is something special.
I will still bet on Kasparov.  The odds, the chances, are better.
Even offer odds if there are any adventurous souls out there.
I still maintain that the program fails because the programmers 
cannot reach their desired goal and do not have the path for 
success within their abilities.
Tomi
`[1;33;43mNet-Tamer V 1.05.1 - Registered

In article <32362869.60EB@superlink.net>, Eric Lucas  writes:
> Now, I gotta be the first one to admit that this is funny stuff below!
> (I'm serious!)  He don't know snot about science, but his humorous prose
> is just brilliant.  "PUT A HEAVY ELEMENT IN THE WHITE HOUSE THIS FALL"
> bumper stickers???  Hee hee hee.  (ROTFL)  What a knee-slapper!  
> 
> Well done, Archie.
> 
  We already HAVE had a heavy element in the White House.
  Or have you forgotten Isaac Asimov's insightful account of the
Reagan years, "I, Ron"?  :-)
-- 
Edward Gedeon, Delco Electronics          |   Member DNRC O-
The above message is a random collection  |
of photons. Any opinion inferred is your  |  "Do you mind if I smoke?"
own problem, bud.                         |           -- Joan of Arc

In article ,
paul_d@postoffice.sandybay.utas.edu.au (Paul Davidson) writes:
>> Hi, I'm a geology student in Brisbane and I'm curious as to whether any
>> Australians in this field use these newsgroups.
>
>Hello Michelle
>
>                                           Yes
>
>Check the "from: " lines in the headers, quite a few of them come from
>"down under" to use that awfull expression.  If you have anything to
>communicate this newsgroup is a good forum.  There is endless drivel from
>various posters but there is also a chance of picking up some usefull
>information, and it is also usefull if you have something to say to
>Australian geologists (or geology students such as myself).
Hi, I'm actually an American student (in Geology), but I visited Australia
a few years ago and really liked the place.  I have a few questions about
the job market there. 
1) Are American nationals allowed to hold jobs there, or would a change of
citizenship be necessary?  I know there are work visas but my
understanding of those was that they are only given to citizens of
Commonwealth nations. (Or have you voted no to the CW?)
2)What are the mining and environmental fields like, in terms of demand
for new geologists?
3)Would an American be welcome if they were planning on moving there,  and
becoming productive members of the community (volunteering, joining local
organizations, etc.)?
I would appreciate anything you could come up with, or any direction you
could point me in for info on the subject.   And if there is anything I
can do for you, please ask.              DSG         

In article <9609062000251185@digcir.cts.com>, david.johnson@digcir.cts.com
(David Johnson) writes:
>I am looking for a program that would do for geology what an excellent
>planetarium program such as 'SkyGlobe' does for astronomy: Permit a
>person to see how landforms have changed--and will change--over time.
>This program would trace the effects of plate tectonics as far back as
>evidence will permit, letting the user see the processes from different
>perspectives and at different rates. The orinterrelationships of the
>dominant forces and pressures could be illustrated, along with which
>major features and rock types were being produced. In those situations
>of considerable uncertainty, such as the orogeny of the Rockies,
>different scenarios could be explored with both their problems and
>advantages explained and explorable.
>
>Does anyone know of such a program? I have never seen reference to one,
>but this is the first time I have ever inquired. The potential for
>students would be great, and I am sure there are many persons such as
>myself who would like to be able to manipulate this ultimate puzzle with
>a computer. One of the most valuable features would be an identification
>of how slight changes in materials or structural composition might have
>made a big difference in the outcome, and it would be great to have
>'what-if' capabilities. Regional supplements could be developed, and
>perhaps I could assemble California on my screen.
>
>If this type of program does not exist, it would be a splendid project
>for advanced students who want to do something that won't sit unused on
>a library shelf!
>
>David Johnson
>Chula Vista  CA
>
>
There is a shareware program called "Erupt" that creates a limited
extrusive landform according to certain variables the user punches in.  It
is limited to very basic forms however, and if memory serves me correctly,
takes up about a meg.  The program you are proposing sounds like a
multi-CD
type of program; however, if you could come up with such a thing, I'm sure
it would be popular, as long as it was done correctly.

Peninsula Geological Society October 1996 lecture
PENINSULA GEOLOGICAL SOCIETY PRESENTS
  Magmatic Arc  Lower Crust - What's Going On?
  by Susan DeBari, San Jose State University
  Volcanism in the Southern Cascades - What's Going On?
  by Michael A. Clynne, U.S.G.S.
DINNER MEETING - Thursday, October 3, 1996
Location:  Stanford University, Stanford, California
5:30 PM-Wine Tasting:  Mitchell Bldg., first floor
6:00 PM-Dinner: . . .  Mitchell Bldg., first floor
7:30 PM-Meeting:       Geology Corner on the quad, Room 105 (formerly Room 320)
Come celebrate the first PGS lecture of the '96-'97 season.
Anyone wishing to attend the lecture only is welcome at no cost.
Stanford faculty and students:  Please make dinner reservations by Monday,
September 30.  Contact Dr. Juhn Liou via his mailbox (and leave check),
Geological and Environmental Sciences Office, Mitchell Bldg. (Rm. 138).  
Make checks out to "PGS".
All others, including faculty and students from other Bay Area universities
and colleges and USGS:  Please make dinner reservations by Monday, Sept. 30.
Contact John Galloway, at USGS, MS-904, 345 Middlefield Rd., Menlo Park, CA
94025, phone 415-329-5688.  Send check made out to "PGS" to John.
Dinner is $22.00.  Includes wine (5:30 to 6:00 PM.), dinner (6:00-7:30
PM.), tax, and tip.
For students from all universities and colleges, the dinner, including the
social half-hour, is $10.00 and is partially subsidized thanks to the
Associates of School of Earth Sciences, Stanford University
Dues for Academic Year 1996-97 ($5.00) should be sent to John Galloway,
USGS, MS-904, 345 Middlefield Rd., Menlo Park, CA 94025.  John's phone:
415-329-5688.
Please check your nearby bulletin board for a map of Stanford University
or contact Vicki Langenheim (415-329-5313; zulanger@mojave.wr.usgs.gov) for
a flyer.  If you wish to have your name removed from this mailing list,
please contact Vicki.
Officers:  Chet Wrucke, President; Mike Diggles, Vice President; Vicki
Langenheim, Secretary; John Galloway, Treasurer
http://caldera.wr.usgs.gov/mdiggles/PGS.html

>>Numerical simulations have been done with Mars-sized objects impacting Earth
>>at long angles; in some cases you _do_ get a Moon-sized ejecta.
Correct. What you don't get is a recognizable crater on the Earth.
The whole mantle is pretty well stirred up by the event. The crust
has to form anew afterwards. No crater. The Pacific Ocean basin
is certainly not the scar of the impact which formed the Moon,
nor of any other single impact.

Leslie A. bond wrote:
> 
> Can we get this out of sci.geo.hydrology?
...and sci.lang?

i.language.japan,sci.life-extension,sci.logic
T.T. Gerritsen (T.Gerritsen@inter.nl.net) wrote:
: ryans@info2000.net (Ryan Swift) wrote:
: [some bombastic language snipped]
: >   This proposed institution, to be organized and constructed before the
: >new millennium, would be the start to those wanting world peace, to those
: >wanting to share a common interest, and the strengthening of the human
: >exploratory spirit.  This article can be looked at as a mere suggestion of
: >collective opinions, or could be looked at as the keystone to a glorious
: >future.
: >The choice is open to the world.  I suggest it chooses wisely.  Those
: >interested in joining the future; let me know. Let the world know.
: However strongly I favour international cooperation of any kind, I 
:hate this kind of bombastic language. For people who don't use our 
:Christian calender, there is no new milennium to come, so it's pretty 
:arrogant to consider the year 2000 a milestone for all mankind. And 
: I'm VERY suspicious indeed of anyone who thinks he is making history 
: and preparing mankind for a glorious future. Please stop this crap and 
: get to work. 
: Tanno Gerritsen
: T.Gerritsen@inter.nl.net
Year 2000 is the end of a millenium, the year 2001 is the start of the 
next millenium.  So, the world peace crowd has an extra year to get their 
act together. :)
(Ah, little do the masses know that on New Year's Eve, 1999, they will be 
celebrating the beginning of the last year of the 20th century, not the 
first year of the 21st century.  But, hey, this is "I'm ignorant 
and I'm proud, don't confuss the issue with facts" America here!)
RonT
Estes Park, CO

In article <3234D312.36AE@navix.net>,
Robert D. Brown  wrote:
>(D) There is a circular impact crater rim centered on Hawaii (the
>Rockies, Central America, the Andes, the trans-Antarctic Mountains,
>... which lie on a great circle of the Earth centered on Hawaii as 
>it lay 65 million years ago.
If so, the Rockies and the Trans-Antarctic Mountains would have been 
the same distance from Hawaii 65 Ma ago. But they weren't. The error
is at least a factor of 2!
John Harper Mathematics Dept. Victoria University Wellington New Zealand

mikejm@westworld.com contributed these words of wisdom to news.admin.net-abuse.misc:
: With people like that washing the dirty dishes of our college
: students, I sincerily fear for the future of our world.
: 
: 
Gawd I LOVE IT!!!!

IFF (If and ONLY if) creationists are willing to treat their "theory" as only a
theory. That is, if they are willing to admit that if proven wrong, they will
give up their religious beliefs.
If not, then they should go back to church and leave science alone.
Bob (soon to be flamed) Strauss

At 12:59 AM 9/11/96 +0000, you wrote:
>
>
>doc.Turi, as you probably know,
>Richter's conjecture has been amply proven by an ex-USGS-guy
>in the Bay Area, whose name I forget but who's been on talkradio;
>in other words, full moons, esp.coincident with perigee,
>are great times to Escape Los Angeles (or wherever)
>to a wooden cottage or great outdoors,
>for some Quality Time with your family!
>       to use this "success" of yours to propogate the rest
>of your crappola is par for the course but, if
>you're going to continue th  behavior, please,
>at least *try* to make a crack at explaining the difference
>between sideral & "tropical" astrology -- or
>are you still using a Ptolemaic ephemerides ?!?
>
>
>--  
-- 
There is no dimension without time.  --RBF (Synergetics, 527.01)
(Brian Hutchings -- ba137@lafn.org)

Chuck Karish wrote:
> 
> I know any number of people who will consider that Mr. Brown's
> position makes no sense at all, as long as he chooses to
> ignore geologic data that contradicts his theories.
The best of your stratigraphic data can be provided good
alternative explanation using the model under development. 
Patience, Chuck, patience.  This is a hobby for me.
> --
> 
>     Chuck Karish          karish@mindcraft.com
>     (415) 323-9000 x117   karish@pangea.stanford.edu

John Harper wrote:
> 
> If so, the Rockies and the Trans-Antarctic Mountains would have been
> the same distance from Hawaii 65 Ma ago. But they weren't. The error
> is at least a factor of 2!
> 
> John Harper Mathematics Dept. Victoria University Wellington New Zealand
Which model of plate motions are you using for this calculation? RDB

In <32359329.5BE2@cadvision.com> Steve Cummings
 writes: 
>
>> Learn how to make "Kufta"
>
>Does preparation of "Kufta" cause an unusual loading on HVAC systems?
No, but, it sure will wreak havoc with the gps satellite signals.  Must
be what has been causing the errors in the units in excess of normal
SA! ;-)
maniacs5...

Hey, this group spends too much time on irrelevant matters,e.g., religion.
I am a coal geologist with a real problem. One of our mines has what is
known in mining jargon as "good roof on the ground." The immediate mine
roof is siltstone(sandy shale), about 20 to 30 ft. thick. No joints,
fractures, faults, or planes of separation. The ground cover in the fall
area is about 600 ft. The falls start with a "cutter"(vertical separation
or crushed zone) in the mine roof down a mine entry adjacent to the
pillars. Once started, the roof will fall to at least 20 ft. or more. The
falls can be stopped in a given entry with timbers and cribs. However, once
stopped, a new fall will begin in another entry 200 to 500 ft. away from
the fall that was controlled.
This problem appears to be due to a stress field(horizontal stress) in the
rock above the coal.
Question to group:  Can any of you academics point me in the direction of
the latest literature on stress fields in rocks? Also, I would greatly
appreciate any ideas from engineering types on learning to live with
stress!
Thanks

Greetings all NLU grads.  It is that time of year again.  Join us in
Monroe at the Coal lab on Bon Aire Dr at 3:00 for BBQ and fellowship. 
Cost will be minimal so come hungry.  It is a fun time for all who
participate so Come one come all.  For more information send e-mail to
gestringer@alpha.nlu.edu or Hayden Chasteen at 47vwsplt@airmail.net or
call the department.  See you There!!!! Hayden

In article  meron@cars3.uchicago.edu writes:
>From: meron@cars3.uchicago.edu
>Subject: Re: good engineering
>Date: Wed, 11 Sep 1996 04:31:35 GMT
>In article , s1045099@iplabs.ins.gu.edu.au writes:
>>>>
>>
>>Tim Flannery suggests that the same process has been occuring in the Pacific 
>>ever since humans entered that environment.   Because we are such efficient 
>>predators we have diminished our capacity to support ourselves in an 
>>environment that we were not evolved for. 
>>
>>He claims that such 'future eating' was part of the reason the Maori evolved 
>>(perhaps not genetically) into such a belligerent race - fighting over 
>>dwindling resources -  and why on Easter Island, for example, human 
>>civilisation collapsed.  
>>
>>It's an interesting read.
>>
>Sounds good.  But you left out the book's title.
Sorry about that.  The book has the ominous title "The Future Eaters".  I 
think it was published in 1994 but I'm not sure of the publisher.  If you'd 
like I can send you the details when I get my copy back from my grandfather 
who is currently borrowing it.

In article <5062d6$lf2@fstgal00.tu-graz.ac.at>,
kirchweg@sztms.tu-graz.ac.at (Gerhild Kirchweger) writes:
>Subject:	Re: Sonnets (Was: A constructive proposal for Archie P.)
>From:	kirchweg@sztms.tu-graz.ac.at (Gerhild Kirchweger)
>Date:	30 Aug 1996 06:40:38 GMT
>
>meron@cars3.uchicago.edu wrote:
>: In article <32262688.7D0A@superlink.net>, Eric Lucas

>writes:
>: >Better than decomposing, I suppose, which is what most Baroque
composers
>: >are doing now!  (Dare I say all?  Not in this crowd!)
>: >
>: Shades of Gary Larson :-)
>
>No, it's Monty Python: "They're decomposing composers, there's less of
them
>every year, ..."
>
>-- 
>
>oo_oo_oo_oo_oo_oo_oo_oo_oo Gerhild Kirchweger oo_oo_oo_oo_oo_oo_oo_oo_oo
>|____ Department of Internal Combustion Engines and Thermodynamics ____|
>|__ Graz University of Technology/ Austria ___Tel. ++43 316 873 7212___|
>oo_oo_oo_o http://fvkma.tu-graz.ac.at/~gerhild/gerhild.html _oo_oo_oo_oo
>
>------------------- Headers --------------------
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>From: kirchweg@sztms.tu-graz.ac.at (Gerhild Kirchweger)
>Newsgroups:
>sci.astro,sci.geo.geology,sci.physics,sci.chem,sci.bio.misc,sci.engr,sci.
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>Subject: Re: Sonnets (Was: A constructive proposal for Archie P.)
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>sci.astro,sci.geo.geology,sci.physics,sci.chem,sci.bio.misc,sci.engr,sci.
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>Date: 30 Aug 1996 06:40:38 GMT
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>
>
oops. sorry I busted in here like this -- looking for a physics NG --
obviously got the wrong door. 
A few kind words take just a few seconds, but the echo lasts for years.
                    - Denis-

Scott Stephens wrote:
snip
> I think he stated that in the Nullabor plain, a vast and remote arid 
> environment, the population density of meteorites is about one per square 
> kilometer!
snip
> If anyone can give me some 
> details on what to look for or any other relevant information I'd be very 
> grateful.
There are many books available on meteorites and what to look for - one of
my favorites is ~Rocks From Space~ by O. Richard Norton (1994) 449p.,
Mountain Press Pub. Co., Missoula Montana USA. He tells you just about
everything you need to know before you go hunting (where to look, what
they look like, how to test what you have found, etc.)
Good Hunting!
Regards,
Andy
-- 
                 Opinions are mine
             Will do research for food
http://www.geocities.com/capecanaveral/2460/Index.html

Amen to that!
WillCarney wrote:
> 
> There are way too many religous post on this group, it is a geology group
> not
> a religous debate group.  Keep it to geology!!!!