Newsgroup sci.geo.geology 36058

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Johan Wevers wrote:
> My boss has probably never heard of the Einstein equations anyway :-)
Don't mean to outdo you but I'm not sure
if my boss even knows who Einstein is.
--
David S. Monroe                          David.Monroe@cdc.com
Software Engineer
Control Data Systems
2970 Presidential Drive, Suite 200
Fairborn, Ohio 45324
(937) 427-6385

In an article, Brian Pickrell wrote:
> I assume that the 20- to 30-degree angle referred to is the angle of the
> object's path relative to the ground.  But what was the object's orbital
> inclination (the angle of its path with respect to the plane of the
> equator)? A path leading from the Yucatan to the central United States
> (the article doesn't specify where in North America the blast debris
> supposedly went) would point more or less directly northward--an orbital
> inclination of roughly 40-140 degrees. 
>  If the angle was this much greater than the Earth's axial tilt, this and
> the fact that the Earth's gravity wouldn't change the direction of the
> object's motion much as it approached, would imply that the object's orbit
> lay outside the plane of the ecliptic.  This would be highly unlikely
> unless it was an extrasolar object.  Does anyone know how large the
> orbital inclinations of comets get? 
   If the object hit at a 20-30 degree angle to the ground, while going S
to N, this could be accounted for be the Earth's axial tilt of about 23
degrees. No need to have something coming in from wildly out of the plane
of the ecliptic. And the Earth's gravity would have some effect, *and*
something could come in from above or below the ecliptic while still
orbiting very close to the ecliptic. Some asteroids have large
inclinations too - Daedalus (an Appollo-type Earth-crosser) has an
inclination of 22 degrees. 1973 NA (another in the same group) has an
inclination of 68 degrees, well out of the ecliptic. But once again, I
don't think you *need* large inclinations to generate this type of impact.
> My understanding was that an impact at hypersonic velocities would form a
> roughly symmetrical fireball, regardless of the angle of impact.  This
> based on very little experimental evidence, since no available gun (at the
> time I was looking into this) could achieve anywhere near the requisite
> velocities.
   True about the fireball, the idea being that the expanssion of the
fireball is much faster than other dynamical processes that could effect
it. And the guns can't fire fast enough to make a fireball - but then
again they fire in vacuum also, a very different case than for any impact
on Earth.
> However, it's worth noting that all impact craters on Earth,
> the Moon, Mars and Mercury that I've ever seen are roughly round.  Could
> an impact form a round crater but still shoot all the debris off to one
> side? 
   Yes. There are at least a few craters on the Moon that do this. There's
one picture of a round crater from Apollo 15 whose ejecta surrounds it by
270 degrees - not 360. The missing sector is uprange from the impact. The
crater is still circular. These happen for impacts between 20-40 degrees.
The crater rim remains circular (from gun studies) down to impact angles
of 10 degrees or less.
> Does the fossil record support this?
[snip]
> ...the article states that plant extinction rates were higher in North
> America than anywhere else.  Is this right?
[snip]
   Your reasoning sounds Ok, although *many* dinosaur discoveries are made
outside N. America. I'm not a palentologist or paleobotanist.
> The Yucatan is part of North America.  I assume they mean the present
> United States and points north.
   Well, sort of - I'd call it part of central america currently, and at
the time of the impact it may not even have been connected to the main
mass of the North American plate.
> Would an effect that is (sort of) observed on Venus, with its dense
> atmosphere and high surface pressure, apply on Earth?  At the minimum, an
> Earth blast wave would be much less massive and pop up above the top of
> the atmosphere much more easily.
   A blast the size of the K-T Event would probably produce an atmospheric
blowout, but it might get downrange a ways first. From conservation of
momentum, a fireball produced from the dregs of the impact (at a
cross-range velocity of 20 km/sec * Cos(25 degrees) = 22.6 km/sec),
incorperating 10 times as much material from the target as from the
projectile, (convervation of momentum, Vfinal = 22.6 / 11), would be
moving north at 2 km/sec. That would rapidly move it downrange, out of the
near-vacuum wake channel, and thus it would have to expand against the
whole (intact) atmosphere, delaying breakout. Could happen - too little
has been done on this.
> Does anybody know how high-powered his gun was?  Could it achieve
> hypersonic velocities similar to meteoric impact velocities?
   The Vertical Gun Range, at Ames, can fire a projectile into a target at
a variety of angles and velocities of up to 6 km/sec. Hypervelocity, but
not fast enough for a lot of things. However, by properly choosing the
target and projectile materials, you can (in a limited way) scale these up
to higher effective velocities. But 6 km/sec is certainly hypersonic.
                                          -Brian Davis
Ref: Melosh, "Impact Cratering, a geologic process", Oxford press, 1989

 Paul B.Andersen  wrote:
>At the html page above I found:
>>
>> v3 = (v1 + v2)/(v1*v2/c^2)
>> 
>> The supporters of the theory don't
>> know that, in fact, the velocity sum
>> equation doesn't conserve energy and
>> momentum, when compared with the
>> calculation using SR's KE and
>> momentum equations.
>>                                                        
>> Example: 
>> 
>>      m_v = 600 MeV 
>> 
>>      KE1 = 50 MeV 
>> 
>>       v1 = 0.399 652*c
>> 
>>       v2 = 0.75*c
>> 
>>       v3 = 0.916059*c
>> 
>>      Velocity SUM: vs = 0.884525*c 
>> 
>> The velocities are different. Energy
>> and momentum are not conserved.
If this is truly representative of how the autodynamics people think of 
energy and momentum conservation, then they don't know what it *means* to 
say that energy and momentum conservation work under special relativity.
Conservation of momentum means that in any process that is not subject to 
"external forces", the total momentum of all objects in the system at the 
end of the process equals the total momentum at the beginning of the 
process.  Similarly for energy.  In relativity, one must use the "total" 
energy of an object, as given by the equation E = m0c^2 + K (where K is 
the kinetic energy) = sqrt((m0c^2)^2 + (pc)^2).
When we say that conservation of energy and momentum "work" under special
relativity, we mean that the statement above is true, regardless of which
inertial frame we analyze the process in, even though the energy and
momentum of each object depends on the frame.  To demonstrate this: 
    1.  Pick a collision or decay process, and work out the velocity, 
momentum and energy of each object, before and after.  I like to use a 
decay process such as lambda-zero --> proton + pi-minus and first assume 
that the lambda-zero is at rest in order to simplify the math.  Of 
course, in this step, you have to assume that energy and momentum are 
conserved in this frame.
    2. Switch to another inertial reference frame.  Use the velocity
addition equation to calculate the velocities of all the objects in the
new reference frame, based on their velocities on the original frame, and 
the relative velocity of the two frames.
    3.  Using the new velocities, and the basic formulas for energy and
momentum, calculate the new energy and momentum of each object.  Of
course, these values will be different from the energy and momentum in 
the original frame.
    4.  Add up the total energy and total momentum, both before and after 
the process, in the new frame.  If you have done all your math correctly, 
the total momentum before should equal the total momentum after, and the 
total energy before should equal the total energy after.
-- 
Jon Bell                         Presbyterian College
Dept. of Physics and Computer Science        Clinton, South Carolina USA

In article <55ceeo$9u8@news.manawatu.gen.nz>,   wrote:
>I am looking for any simulation of the change in the position of the
>continents that has taken place throughout geological time. If it goes
>further and indicates mountain building, climate variation through
>time and the variation in the distribution of plant and animal
>species, this would be even better. Can anyone help?
A typical base system will give the outlines of the major tectonic
plates in the last 200 million years, their pole-path motions,
and constraints that obey the algorithms of spherical geometry.
Users than can attach their own geographic information such as
you describe and prescribe their own pole-path motions.
I've seen attachments for volcanic activity and petroleum basin location
done.   You can go back more than 200 million years, but scientists
have more divergent opinions of what happened then.

Many Physical Geology texts assert that surface waves are responsible for 
most damage and the strongest shaking.  I seem to recall from graduate 
school that shear waves do the job.
Those textbooks citing shear wave motion as most damaging are authored by 
scientists with closer ties to the seismological community that those 
blaming surface waves.  It is obvious that both points of view can not be 
correct.
How can fundamental contradictions persist for decades in those books used 
to teach introductory courses?
Don Stierman - Associate Professor - University of Toledo 

Douglas R. Grant wrote:
> 
> Announcing a web page that offers a wide selection of colour photos of
> Canadian landscapes and landforms with explanatory description in simple
> terms.
> 
> http://sts.gsc.nrcan.gc.ca/landf
> 
> The site is maintained by the Terrain Sciences Division of the Geological
> Survey of Canada.
> 
> Eventually 1000 photos will be available; at present about 100
> in Newfoundland are accessible for browsing.
> 
> THE AUTHOR
> --
> drgrant@gsc.emr.ca
That webb page is unavailable as of Saturday morning. Did it move or is
it temporarily down?

Amnon Meyers wrote:
> 
> Einstein's velocity sum equation is inconsistent with the KE
> and momentum equations, as shown by plugging in values.
> 
> See
>    http://www.autodynamics.org/Professional/velocitysum.html
> 
First of all, if you wish that these pages be taken seriously, you 
might want to make them a bit more clear in presentation.  The 
"derivation" on this page in particular is quite hard to follow.
> Warning!  You may see that the Autodynamics equations are
> self-consistent, on the same page.
In your example, you state m_v = 600 MeV.  I suspect that means
gamma*m = 600 MeV, in which case your beta_1 is the correct velocity
for the mass (which is 550 MeV), and gamma = 1.0909.  
I suppose then that beta_2 is supposed to be the relative velocity
between two frames, and that beta1 and beta2 are supposed to be
collinear.  
Then, I understand the calculation of the velocity sum = .8845.  
This is correct, given beta1 = .3997 and beta2 = .75.  (however
the velocity sum equation as presented is incorrect.  The c^2 in 
the beta1beta2 term in the denominator isn't supposed to be there.
Can you explain how beta3 was calculated?  It's not readily apparent.
Todd
------------------------------------------------------------------
Todd K. Pedlar   -  Northwestern University - FNAL E835
Nuclear & Particle Physics Group
------------------------------------------------------------------
Phone:  (847) 491-8630  (708) 840-8048  Fax: (847) 491-8627
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In article , T Bruce Tober
 writes
>In a rather exuberant mood, Theresa Murison  writes
>>In article <326675E1.49A9@tam2000.tamu.edu>, "Dawn C."
>> writes
>>>When replying to one of these MASS newsgroup messages (LIKE HELP ME)
>>>please delete all irrelevant newsgroups.
>>>
>>>That will make a lot of people happy.
>>
>>
>>Y'know, *I'D* be happy if you'd tell me how to do it?!  Peace.
>
>Since you're using Turnpike, look above your message editing window to
>the small window that says Newsgroups and simply cursor over the
>inappropriate newsgroup names and hit delete
Got it before I saw your post - thanks anyway.
-- 
Theresa 

Triple Quadrophenic (Frank_Hollis-1@sbphrd.com.see-sig) wrote:
: In article <553qf1$c8o@news2.acs.oakland.edu>, 
: jbartlo@ouchem.chem.oakland.edu (Joseph Bartlo) says...
: Nope. I've never seen this definition, and I doubt that anybody uses it. 
: Apart, that is, from people who've erroneously stated that increased 
: planetary rotation decreases gravity and can't admit they made a boo-boo.
No, you cannot admit you are wrong.  Gravity includes both
gravitational attraction and centrifugal effects.  I can
provide many references showing that.  More importantly,
measurements confirm that.
Joseph

Wrong again

The correct URL is http://sts.gsc.emr.ca/page1/landf/.
Darrell Nations, R.G.
Nations Groundwater Associates
>Douglas R. Grant wrote:
> 
> Announcing a web page that offers a wide selection of colour photos of
> Canadian landscapes and landforms with explanatory description in simple
> terms.
> 
> http://sts.gsc.nrcan.gc.ca/landf
> 
> The site is maintained by the Terrain Sciences Division of the Geological
> Survey of Canada.
> 
> Eventually 1000 photos will be available; at present about 100
> in Newfoundland are accessible for browsing.
> 
> THE AUTHOR
> --
> drgrant@gsc.emr.ca

Todd K. Pedlar wrote:
> 
> Amnon Meyers wrote:
> >
> > Einstein's velocity sum equation is inconsistent with the KE
> > and momentum equations, as shown by plugging in values.
> >
To all people participating in this thread! Please remove 
alt.prophecies.nostradamas from the thread.
Thanks

In article , wa2ise@netcom.com (Robert Casey)
wrote:
> In article <31OCT199604304697@kelvin.jpl.nasa.gov>
baalke@kelvin.jpl.nasa.gov (Ron Baalke) writes:
> >
> >The asteroid that wiped out the dinosaurs was
> >particularly deadly because it hit the Yucatan peninsula
> >at an oblique angle, spreading a killing zone of matter
> >downrange, according to a new study. Color
> >transparencies are available.
> >
> (more plant extinctions in North America implys the astroid that hit Yucatan
> came in on an angle and scattered debres and stuff northward)
> 
> It should be fairly easy to confirm, or at least add more evidence,
> by looking to see if there is more asteroid debres (irridium) in
> North America than say South America, Europe, etc.  And that there be
> an intermediate amount in Siberia, and less in China.  
> 
> Or did the stuff hang in the atmosphere long enough that the distribution
> became even around the planet?
The original statement is that more material was sent "downrange" creating
a "killing zone." Which to me states that if true, there has to be more
iridium and other elements.
But, I see a big conflict in this hypotheses based on other information
posted in this newsgroup a few months ago. Someone asked a question about
impact craters being oval instead of round if a meteor impacted at an
angle. There were several answers that stated that it has been shown that
even at an angle, the crater is round. Wouldn't this mean that the debris
is thrown out relatively equally 360 deg.? If so, the idea of the oblique
impact throwing more debris towards North America is as questionable as
the entire idea that an impact wiped out the dinosaurs.
Lanny
-- 
*********************************************************
/  Lanny R. Ream     lream@comtch.iea.com               /
/  Publisher,                                           /
/    Mineral News--The Mineral Collector's Newsletter   /
/  Owner/Publisher   LR Ream Publishing                 /
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*********************************************************

EVIDENCE OF LIFE FOUND IN SECOND MARS METEORITE
Written by Ron Baalke
November 1, 1996
In a press conference yesterday, scientists in England claimed that they've
found traces of organic material in a second Mars meteorite, EETA 79001.  
The same team also reported that they've found organic matter in the ALH 84001
meteorite, the same meteorite that a NASA team reported last August as having 
possible microfossils.  A critical finding by the British team is that
EETA 79001 contains significant amounts of organic material, up to 
1,000 parts per million.  This organic material has yet to be identified.
The British team consists of Ian Wright and Colin Pillinger from Britain's 
The Open University, and Monica Grady from London's Natural History Museum. 
The EETA 79001 meteorite was found in Elephant Morraine in the Antarctic, and 
was the first meteorite found during the 1979-1980 collecting season.  
EETA 79001 is classified as a shergotite, the most common subgroup of the 
Mars meteorites.  EETA 79001 weights 7,900 grams (17.4 pounds), and is the 
second largest Mars meteorite ever found - only the Zagami meteorite is larger.
What makes the findings from the British team particularly exciting, is that 
EETA 79001 is much younger than ALH 84001.  EETA 79001 is only 180 million years
old - very young on the solar system scale - and was launched into space 
from Mars 600,000 years ago.  The young age of this meteorite suggests that 
life existed on Mars much longer than what was previously thought, and that 
there is a possibility that life could still exist on Mars today. 
For more info on Mars meteorites, see the Mare Meteorite home page:
http://www.jpl.nasa.gov/snc/
     ___    _____     ___   
    /_ /|  /____/ \  /_ /|      Ron Baalke     | baalke@kelvin.jpl.nasa.gov
    | | | |  __ \ /| | | |  Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   Pasadena, CA    | Kindness is one thing you
/___| | | |  ___/    | |/__ /|                 | can't give away -- 
|_____|/  |_|/       |_____|/                  | it always comes back.

We live in exciting times.. thanks for the update!

In article , lream@comtch.iea.com
(Lanny R. Ream) wrote:
> But, I see a big conflict in this hypotheses based on other information
> posted in this newsgroup a few months ago. Someone asked a question about
> impact craters being oval instead of round if a meteor impacted at an
> angle. There were several answers that stated that it has been shown that
> even at an angle, the crater is round. Wouldn't this mean that the debris
> is thrown out relatively equally 360 deg.? If so, the idea of the oblique
> impact throwing more debris towards North America is as questionable as
> the entire idea that an impact wiped out the dinosaurs.
At the annual meeting of the Geological Society of America this past
Tuesday, Dick Buffler of the University of Texas, Austin, discussed
preliminary seismic evidence that the Chicxulub crater does, indeed, appear
to be roughly round but that the ejecta rim seems to be absent to the north
in the Gulf of Mexico. He did not discuss any implications.
David Schoonmaker
amsci.org
David Schoonmaker
davids@amsci.org

bf>  no ways 
bf>  to increase the half-lives of elements, so they are going to take
bf>  thousands of 
   hmm? are you by any chance in Cummings Class ?

Readers of this thread may be interested in the following:
Natural Catastrophes during Bronze Age Civilisations:
Archaeological, Geological and Astronomical Perspectives.
A conference at Fitzwilliam College. Cambridge. 11th-13th July 1997
This SIS Cambridge conference will bring together historians,
archaeologists, climatologists and astronomers in order to discuss
whether the 'giant comet' hyopothesis brought forward by
neo-catastrophist astronomers such as Victor Clube, Bill Napier, Sir
Fred Hoyle, David Asher, Mark Bailey, Duncan Steel et al. can be
substantiated by the archaeological, climatological and historical
record.
Astronomy
Research in the field of astronomical neo-catastrophism and impact
cratering has quickened its pace since the early 1980s. An increasing
number of astronomers have suggested that a series of cosmic disasters
punctuated the Earth in prehistoric times. Scholars such as Victor
Clube, Bill Napier, Mark Bailey, Fred Hoyle, David Asher and Duncan
Steel claim that a more 'active' and threatening sky might have caused
major cultural changes of Bronze Age civilisations, belief systems and
religious rituals. Can the astronomical evidence brought forward by
these astronomers be substantiated by historical, archaeological and
climatological evidence? 
Culture
In light of new astronomical and archaeological theories and the
emergence of scientific neo-catastrophism, it seems necessary to
re-assess the origins and cultural implications of apocalyptic
religions and catastrophe traditions in ancient mythologies and
rituals. In particular, the significant cultural and religious changes
at the beginning of the Bronze Age and those which occurred after its
final collapse will be re-evaluated. 
Details at http://www.knowledge.co.uk/xxx/cat/sis/cambconf.htm

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D. Schoonmaker wrote:
> 
> At the annual meeting of the Geological Society of America this past
> Tuesday, Dick Buffler of the University of Texas, Austin, discussed
> preliminary seismic evidence that the Chicxulub crater does, indeed, appear
> to be roughly round but that the ejecta rim seems to be absent to the north
> in the Gulf of Mexico. He did not discuss any implications.
> 
> David Schoonmaker
> amsci.org
I seem to remember recently reading a journal article by 
a team of geologists, who reported a meteoritic fragment in
a deep see core sample from the central Pacific Basin.
This in itself is unremarkable news, but it happens that
the meteoritic fragment they found was positioned *exactly* within
the K-T boundary layer of the core sample...within the
zone with the iridium spike.    The researchers postulated
that perhaps the impactor hit at an oblique angle, comming
in from the east, and that the meteoritic fragment was part of
the down-range ejecta blanket. This latest news that Baalke posted 
seems to support these guys' earlier hypothesis. Unfortunately, I 
forgot where I read this research paper.  Does anyone 
know, and could they post the complete citation?

Todd K. Pedlar wrote:
> 
> Amnon Meyers wrote:
> >
> > Einstein's velocity sum equation is inconsistent with the KE
> > and momentum equations, as shown by plugging in values.
> >
> > See
> >    http://www.autodynamics.org/Professional/velocitysum.html
> >
> 
> First of all, if you wish that these pages be taken seriously, you
> might want to make them a bit more clear in presentation.  The
> "derivation" on this page in particular is quite hard to follow.
> 
> > Warning!  You may see that the Autodynamics equations are
> > self-consistent, on the same page.
> 
> In your example, you state m_v = 600 MeV.  I suspect that means
> gamma*m = 600 MeV, in which case your beta_1 is the correct velocity
> for the mass (which is 550 MeV), and gamma = 1.0909.
> 
> I suppose then that beta_2 is supposed to be the relative velocity
> between two frames, and that beta1 and beta2 are supposed to be
> collinear.
> 
> Then, I understand the calculation of the velocity sum = .8845.
> This is correct, given beta1 = .3997 and beta2 = .75.  (however
> the velocity sum equation as presented is incorrect.  The c^2 in
> the beta1beta2 term in the denominator isn't supposed to be there.
> 
> Can you explain how beta3 was calculated?  It's not readily apparent.
> 
> Todd
> 
> ------------------------------------------------------------------
> Todd K. Pedlar   -  Northwestern University - FNAL E835
> Nuclear & Particle Physics Group
> ------------------------------------------------------------------
> Phone:  (847) 491-8630  (708) 840-8048  Fax: (847) 491-8627
> ------------------------------------------------------------------
> WWW:    http://numep1.phys.nwu.edu/tkp.html
> ------------------------------------------------------------------
I'm absolutely SURE that Nostradams did NOT know who EINSTEIN was. Now, 
please take this elsewhere.
-- 
mailto:braz@mnw.net
mailto:braz@usa.systar-corp.com
http://www.mnw.net/brazil
Assembler is not for the meek...

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In article <327A9A3E.51B3@oeonline.com> Shelley  writes:
>We live in exciting times.. thanks for the update!
So do the Martians!
-- 
David Pollen                                             pollen@netcom.com
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Free A. Square!                                   Long Live Byron the Bulb!
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
                         See you at the Omega Point!
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

You certainly have jumped into the deep end of the pool. The questions you
pose have not all been satisfactorily answered yet. Rather than attempt to
give my understanding of the current theories and hypotheses surrounding
plate tectonics (the name is here to stay I'm afraid), I would advise you
to expand your thinking beyond the present and consider the past as well.
The continents are now certainly clustered more in the north than south.
It has not always been so. Same with the avoidance of equatorial
latitudes. Pick up a good historical geology text. It should give you an
indication of past plate positions. 
As far as what drives the plate tectonic machine, several ideas have been
put forward. Some say that a single zone of convection exists in the
mantle while others suggest a segregation between upper mantle and lower
mantle convection cells with plumes rising from the core/mantle boundary
that penetrate both regions. Other ideas are out there.
Your observation that the land masses appear roughly triangular is
interesting. If significant, I wonder if it has anything to do with the
fact that the continents tend to rift at triple junctions? Also, please
remember that plates are composed of oceanic as well as continental crust
and move as a unit. For instance, the continent of Australia is on the
same plate as India, with much oceanic crust in between. This plate is
nowhere near triangular.

Donald J. Stierman wrote:
> 
> Many Physical Geology texts assert that surface waves are responsible for
> most damage and the strongest shaking.  I seem to recall from graduate
> school that shear waves do the job.
> 
> Those textbooks citing shear wave motion as most damaging are authored by
> scientists with closer ties to the seismological community that those
> blaming surface waves.  It is obvious that both points of view can not be
> correct.
> 
> How can fundamental contradictions persist for decades in those books used
> to teach introductory courses?
> 
> Don Stierman - Associate Professor - University of Toledo 
   As a layman I've often wondered the same thing.  Both the Pressure
and Shear waves are body waves, which is why deep focii earthquakes
cause considerably less damage than those whose epicenters are shallow.
   I've seen seismographs supposedly showing the different P, S, and L
waves, and by far the L waves are both the strongest and longest
wavelength.
   In the Loma Preita earthquake I am fairly certain that I felt the
separate arrival of the P, S, and L waves.
                                    Bill