Shoemaker-Levy 9 revisited:
                                                                          or
          The Geology of the K/T Impact Craters on Earth
                                      or
      Wiping out the Dinosaur with Five Simultaneous Impacts…
                                      or
Thomas J. Teters                                                                                                         July 28, 2005

  Way back in July 1994, our solar system was visited by a ‘string of pearls’ known as the Shoemaker-Levy 9 comet,
this asterism stuck Jupiter with the force of thousands of our largest nuclear bombs and did it some 13 times in
the interval of several days. Since Jupiter is composed mainly of gases there were just a remnant ‘black eyes’ left
behind in its atmosphere, and these disappeared completely after several weeks.
Fig 1: Post impacts, polar orthographic mosaic of Jupiter in 2.0 micron infrared by the 5-m Hale
                                                                     Telescope at Mt. Palomar, July 1994 (Cornell  University/Caltech/Air & Space Museum).
 But, when this happens on Earth millions of tons of rock, dust & water are thrown up through the atmosphere and
in the case of large (> 8KM) asteroids; matter will even reach escape velocity. For the next several days that ejecta,
containing associated geochemical anomalies, iridium, gold, rhenium, arsenic, antimony and selenium, rock dust, broken
or brecciated rocks, shocked quartz, impactites or impact glass such as tektites, coesite, stishovite, a higher pressure
polymorph of quartz, meteoric oxides and water will rain down upon the planet depositing a world-wide dust layer.
In the K-T event this was anywhere from a meter to a centimeter thick layer, depending how far it was away from
the Chicxulub crater.  The following months most vegetation will have died and a nuclear winter could last for several
years.
 This multiple event may have happened to earth. In 1980, a physicist Luis Alvarez and his geologist son Walter Alvarez,
suggested that the K-T event, the extinction of the dinosaurs and up to 80% of the other species, some 65 million years
ago may be due to the impact of the Chicxulub asteroid. That occurrence is pretty much accepted nowadays.  Around
this time there were also several other very large craters produced.

The Boltysh Crater in the Ukraine and & the Silverpit Crater off the eastern coast of  England. Aged by radioactive
40Ar/39Ar decay products the Boltysh crater yielded an age of 65.17±0.64 million years, almost exactly the age of
Chicxulub crater in the Yucatan.  All three of these craters exhibit impact glasses and ejecta of breccia.
Fig 2: Location of the 24 Km Boltysh Crater in the Ukraine,
                                                                                               near Kiev was discovered during oil prospecting.
  This type of event has occurred several times and there are at least 5 major ‘mass extinction events’ recorded in
Earth's geologic history. Some scientists forecast that we are overdue for another visit from space. Besides the
obvious destruction of organic life there are major geological events that occur and mark these event for 100’s of
millions of years, if you are wise enough to read the signs.
Fig 3: Outcrop of strata crossing the Cretaceous-Tertiary (K/T)
                                                                                            boundary at Brazos River, Falls County, Texas; note pick and
                                                                                            shovel for scale. By Alan Hildebrand, Geological Survey of Canada 1992.
  An event such as this leaves evidence of shock metamorphism, which is manifested in the presence of
shattercones, circular structures with raised rims, an area of central uplift and sometimes a peak in the center.

  A recently well studied crater at the mouth of the Chesapeake Bay, from only 35.5 million years ago was
found to have crushed together the water tables in area and faulted rock all the way down to the layer of
undifferentiated crystalline basement rock over a kilometer deep.
Fig 4: Location of the Chesapeake Crater  and it's multiple faults, by Wylie Hoag
 The Yucatan or Chicxulub Crater, located on the northwest coast of Yucatan, was discovered some 15 years ago and
determined that a 10-15-km object hit earth. The Chicxulub melt-rock is dated by 40Ar/39Ar ½ life at 65.07 +-0.1 Ma
and impactor created a 180 km crater.  Exhibiting rock types of limestone, anhydrite (a calcium sulfate mineral),
a polymict breccia consisting of igneous-textured microcrystalline clasts with shocked quartz xenoliths, and vesicular
and ropy textured phyllosilicate clasts, which look like altered fragments of glass, both produced by shock melting.
Fig 5: A 0.32mm shocked quartz grain from intracrater breccia sample Y6 N14 of the Chicxulub crater located
                                                                              ~50 km from the crater's center and penetrated ~500 meters of impact melt and breccias at its base.
                                                                              Impact is the only natural process known to produce shock waves of sufficient strength to  cause deformation
                                                                              of this type. (Taken in cross-polarized light by Alan Hildebrand)
 The breccia contains clasts of sedimentary carbonates, evaporites, recrystallized sandstone, granitic gneisses and mica
schists in a carbonate-rich matrix.

Other minerals found in meteorites  Full text found here:
Metallic Iron
Metallic iron minerals make up the largest percentage of iron meteorites and stony iron meteorites & chondrites.
Kamacite--this is essentially metallic iron with up to 7.5% nickel
Taenite--this is iron with more than 25 percent nickel
Plessite--this is not a mineral, but is a mixture of fine-grained kamacite and taenite.

Iron Sulfides
Troilite--FeS--Iron sulfide similar to the earthly mineral pyrrhotite.
Daubreelite--FeCr2S4--

Iron Carbides
Cohenite--(Fe,Ni,Co)3C--is iron carbonate
Haxonite--(Fe,Ni,Co)23C6--is a cubic iron carbide
Phosphides
Schreibersite and Rhabdite--(Fe,Ni)3P--Iron-nickel phosphide

Oxides
Chromite--FeCrO4--This ore of chrome
Magnetite--Fe3O4--A common ore of iron
Corundum--Al2O3--same mineral as rubies & sapphires

Carbon
Graphite--C--The common mineral of pencil lead
Diamond--C-- high temperature and pressure of meteorite impact,
sometimes form diamonds. Canyon Diablo meteorites have some.
Lonsdaleite--C--A hexagonal polymorph of diamond (diamond is cubic).

Silicate Minerals
Pyroxenes-- found particularly chondrites and achondrites. The following gradually decreases in magnesium and increases iron content:
Enstatite--Mg2Si2O6--The end member--the one highest in magnesium.
Bronzite--(Mg,Fe)SiO3--more iron than enstatite and more magnesium than hypersthene.
Hypersthene--(Mg,Fe)SiO3--mineral similar to bronzite in many ways, but having more iron
Orthoferrosilite--FeSiO3--This is the other orthopyroxene end member. It has the most iron and the least magnesium.

Clinopyroxenes, (monoclinic crystal structure) diopside (CaMg(SiO3)2), hedenbergite (CaFeSi2O6), augite ((Ca,Na)(Mg,Fe,Al)(Si,Al)2O6)
                          and pigeonite ((Mg,Fe,Al)(Mg,Fe)Si2O6) are also found in meteorites particularly achondrites.
Olivine--(Mg,Fe)2SiO4--formed at great depth, the Earth's mantle may have significant olivine. in some pallasites with forsterite
containing the most magnesium and fayalite having the most iron.

Feldspars--calcium, sodium. aluminum silicates--
Phylosilicates or clays are found in some meteorites.
************************************************************************
Minerals of the Canyon Diablo
The mineralogy of Canyon Diablo meteorites depends on whether they have been shocked by impact.
While all of the specimens were shocked to some degree, some specimens found around the crater
rim show very different mineralogy.

The less altered mineralogy is typical of iron meteorites. The important minerals are:

Kamacite--this iron nickel alloy makes about 90 percent of specimens.
Taenite--the other iron nickel constituents taentie and plessite make up 1 to 4 percent of the material.
Schreibersite crystals occur as skeletal blades. This is a very hard mineral that will ruin a saw blade
     unfortunate enough to be put to the task of cutting a Canyon Diablo.
Troilite--this iron sulfide occurs as nodules up to 50 mm across or as elongated lenses. Troilite may be
     mixed with graphite, daubreelite, chromite, or base metal sulfides. Troilite-graphite masses may make
     up about 8.5 % of specimens.
Graphite occurs as large bodies within iron or in separate masses.
Cohenite, an iron carbide, is common. This mineral is even harder than Schreibersite.
Haxonite, chromite and silicates are also found.

The specimens that were subjected to greater shock show partial melting, recrystallization, neumann banding
and other deformation. Perhaps the most well-known shock effect is the transformation of graphite to diamond
and lonsdaleite. These take the from of tiny dark masses that become evident on sawing. A diamond blade will
move aside when it hits one of these.

Millerite is one of several minerals that is routinely found (albeit in scarce quantities) within iron-nickel meteorites.
*******************************************************************************************************
Meteorite Market (below a list of falls, for which he has inventory)
Albareto L4 Chondrite
Alfianello L6 Chondrite
Allende, Chondrite (CV3)
Barwise H5 Chondrite
Begaa LL3 Chondrite
Bensour LL6 Chondrite
Béréba Eucrite achondrite
Bilanga, Achondrite (diogenite)
Boguslavka Hexahedrite
Boxhole IIIAB Iron
Brenham Pallasite
Brahin Pallasite
Bur-Abor, Iron (Om)
Campo del Cielo Iron (Og)
Canyon Diablo, Iron (Og)
Cape York, Iron (Om)
Chinga, Ataxite Iron
Clovis #2 L6 Chondrite
Dalgety Downs , Chondrite (L4
Dar al Gani 319 Polymict Ureilite
Dar al Gani 380 Eucrite achondrite
Dar al Gani 391 Eucrite achondrite
Dar al Gani 400 Lunar
Dar al Gani 412 CK5
Dar al Gani 475 H3.4 Chondrite
Dar al Gani 476 (Martian Basalt)
Dar al Gani 477 L6 Chondrite
Dar al Gani 749 CO3
Dar al Gani 779 Howardite Achondrite
Dhofar 018 Howardite Achondrite
Dhofar 125 Acapulcoite achondrite
Dhofar 132 Ureilite achondrite
Dhofar 207 H3.4/3.5 chondrite
Dimmitt, Chondrite (H4)
Dresden H5 Chondrite
El Gouanem Ureilite Achondrite
El Hammami, Chondrite (H5)
El Kachla Impact melted chondrite
Estherville Mesosiderite
Etter, Chondrite (H6)
Floyd L4 Chondrite
Gao/Gueine H5 Chondrite
Gao-Guenie (b) CR Carbonaceous Chondrite
Ghubara, Chondrite (L5)
Gibeon Iron (etched slices)
Gibeon whole irons
Gobabeb H4 Chondrite
Gold Basin, Chondrite (L4)
Gujba Bencubbinite
HaH237 CH Chondrite
Hardtner L6 Chondrite
Henbury, Iron (Om)
Hope Creek LL6 Chondrite
Hunter LL5 Chondrite
Igdi Eucrite
Imilac, Pallasite
Jilin, Chondrite (H6)
Juvinas Eucrite achondrite
Kabo H4 Chondrite
Kilabo LL6
Korra Korrabes H3 Chondrite
Lone Star H4 Chondrite
Loop (a) L6 Chondrite
Mayfield H5 Chondrite
Miles iron with silicate
Millbillillie, Achondrite (Eucrite)
Mont Dieu, Iron II Of
Monze L6 Chondrite
Mt. Egerton aubrite achondrite
Mundrabilla, Iron (Of, IRAN)
Murchison, Chondrite (CM2)
Northbranch, Chondrite (H5)
NWA 060 CK5
NWA 479 Lunar
NWA 530 CR2 chondrite
NWA 725 Acapulcoite achondrite
NWA 753 Rumuruti Chondrite
NWA 801 CR2 Chondrite
NWA 869 Brecciated Chondrite
NWA 987 L3.8 Chondrite
NWA 1068 Martian Basalt
NWA 1109 Eucrite achondrite
NWA 1242 Mesosiderite
NWA1465 C3 Chondrite
NWA1882 Mesosiderite
Odessa, Iron (Og)
Park Forest L5 Chondrite
 Plainview H5 Chondrite
Portales Valley H6 Chondrite
Pultusk H5 Chondrite
Rammya H5 impact melt
Sahara 97103, Enstatite Chondrite (EH3)
Sahara 99555, Angrite
Saratov, Chondrite (L4)
SAU 005/008 (Martian Basalt)
Seymchan Pallasite IIE
Sikhote-Alin, Iron Fragments (Ogg)
Sikhote-Alin, Iron Individuals(Ogg)
Steinbach IVA Iron
Suizhou L6 Chondrite
Sutton H5 Chondrite
Tafassasset Brachinite-like achondrite
Tagish Lake (CI2?)
Tambo Quemada IIIAB Iron
Tatahouine, Achondrite (Diogenite)
Taza Plessitic Octahedrite
Tishomingo Ataxite
Thuathe H4/5 Chondrite
Toluca IAB Iron
Tsarev H5 Chondrite
Udei Station, Silicated Iron
Uwet, Hexahedrite
Vaca Muerta Mesosiderite
Wabar IIIAB Iron
Wellman (f) H3.5 Chondrite
Yorktown H5 Chondrite
Zag, Morocco, Chondrite
********************************************************************************************************
  The image below displays a striking semicircular alignment or Cenote Ring around southern hemisphere of the crater.
This was realized through information gathered due to oil research drilling in the area by PEMEX geophysicists Antonio
Carmargo-Zanoguera and Glen Penfield.
  Further digs proved that trees were flattened up to a 1000 km. away and the impact was partially in a shallow sea so
there were tsunamis which radiated across the Gulf of Mexico. Compare this to the 1908 Tunguska event where trees
were only flattened out to 30 - 40 km. And sent its shock wave TWICE around the world!
Fig 6:  A gravity map of The Chicxulub crater in Yucatan, Mexico.  The white dots are Cenotes (after the
                                                                       Maya word dzonot) or limestone sinkholes. Notice the highlighted semicircle at the southern outer
                                                                       ring of the crater.
  Our next crater of interest is the Silverpit Crater, 80 miles east of the Yorkshire, England coast in the North Sea.
While this crater lies on a chalk layer, again the crater is manifested by the standard shock geology, cohesite or stishovite
presence, shattercones, raised rims or central emergence, circular structure, broken brecciated rocks, impact glass or
impactites and meteorite oxides.

  This crater is 12 miles (20 km) wide, with some 9-10 concentric rings stretching from the central peak out almost 10km.
The central bowl shaped crater is about 2 miles (3 km) and buried under shale & sandstone sediment almost a kilometer
deep and at the bottom of a 130-foot-deep sea. The impactor is estimated to have been a 7 million-ton, 120m-wide object
which struck the earth at 20km/s. Its location was theoretically suggested by statistical prognostication. To further prove
that craters with these characteristics are impact origin regardless of the planet/moon they hit. Silverpit looks almost
exactly like the Lunar crater Mare Orientale & the Valhalla crater on Jupiter's moon Callisto, there are similar craters on Europa.
Fig7: Silverpit Crater, North Sea Fig 8: Mare Orientale
Fig 9:  Valhalla on Callisto
Notice the concentric rings on all three of these craters.  There is some debate about the impact origin of the Silverpit
crater, cast by Christian Koeberl, a geochemist at the University of Vienna in Austria, when he wrote in the journal Nature
that Silverpit may be a sinkhole depression caused by salt withdrawal.

   Sankar Chatterjee, the primary investigator, a paleontologist at Texas Tech University in Lubbock, says The Shiva Complex
is a large 600 by 400 kilometers teardrop shaped (because the impactor struck the Earth at a low angle) underwater crater,
off the western coast of India, and was made by an enormous impactor measuring 40 kilometers across.

Fig10: Diagram of Shiva impact area. Credit: Sankar Chatterjee.
  From the synopsis of Chatterjee’s paper he reinforces the theory that, "Evidence is accumulating that there were multiple
impacts across the Cretaceous-Tertiary boundary such as the Chicxulub crater in Mexico, Boltysh crater in Ukraine, Silverpit
crater in North Sea, and the Shiva crater offshore western India."
 Many of these structures are some of the best hydrocarbon producing sites in the world. Shiva is one of them.
  Its morphology is much the same as the previous craters, concentric geophysical rings, a collapsed outer rim, an underwater
central spire as high as Mount Everest, dated as 65 million years old. The central uplift called, Bombay High, has veins of
pseudotachylite (formed largely by frictional melting along faults where rocks moved at or after an impact event) and a core
of Neoproterozoic granite (938±13 Ma)  that rebounded upward for more than 5 km.
  The age of the crater is inferred from its a 500,000 mile2 brecciated lava Deccan Traps, which encase alkaline igneous rock
spires, rich in Iridium. Paleocene sediments, isotopic dating ejecta melt, the magnetic anomaly of the Carlsberg Ridge, seismic
reflection, and structural and drill core data all indicate the possible impact origin of the Shiva structure. Siderophile ("iron-loving")
elements & rock type are, iridium-rich alkaline melt rocks, shocked quartz, Ni-rich spinels (MgAl2O4, Magnesium Aluminum Oxide),
Ni-rich vesicular glass, sanidine, a polymorph of Potassium Aluminum Silicate KAlSi3O8, spherules, fullerenes (C60-Buckyballs),
glass-altered smectites (refers to a family of non-metallic clays primarily composed of hydrated sodium calcium aluminum silicate,
bentonite), and tsunami deposits. And finally the K-T clay boundary layer in India is one meter thick- the thickest in the world.

  At the time of the K-T extinction, India was an island located over the Reunion hotspot. The impact was so intense that it sheared
and deformed the lithospheric mantle across western India, contributed to major plate reorganization in the northwestern Indian
Ocean. As well as displaced the Carlsberg Ridge 500-km, which initiated rifting between India and Seychelles Islands. The oblique
impact may have generated spreading asymmetry, possibly linked to the sudden northward acceleration of the Indian plate in Early
Tertiary. Oil companies and the Indian government control the site where Shiva is located, and access is extremely limited, so the
Shiva crater is still a non-pier reviewed hypothesis. G

  The Small Point Investigation is on a structure off the coast of Maine. There is evidence implying a large impact crater in the
Gulf of Maine. Its most probable age is K-T boundary, but it lacks definitive ages from impact materials. Regional apatite-
Ca5(PO4)3(F,Cl,OH) fission track data, which indicate a temperature above 110*C F and show a reheating event probably beginning
in the late Cretaceous. The most distinctive features of the Small Point crater are its topographic and magnetic expressions.
"Now researchers are looking at another location off the coast of Maine, near Small Point, where there is evidence of another
impact. It could well be that the dinosaur killing asteroid was not alone when it slammed into the Earth."  (H)

 Two scientists, Dominic Manzer, an engineer from NASA, and Dallas Abbott from the Earth Observatory at Columbia University,
are in preliminary stages of looking at this event. As yet they have not found strong evidence to support their theory.  Manzer
and Abbott presented their initial findings on what they are calling the Small Point crater in 2004 at a regional meeting of the
Geological Society of America in Halifax, Nova Scotia.

  The two were studying the magnetism of the crust around the Gulf of Maine when they noticed an anomaly. They detected a
very large, and as yet, unexplainable, difference in the magnetism of the crust from the Gulf area from that of the surrounding
areas. Additionally, there is an arrangement of ridges on land that channels rivers and streams in Maine and Massachusetts along
arcs that might be ridges of the western part of an eroded crater.
Fig 11:  USGS Image Small Point, Maine, cropped to the
                                                                                                      center of the Small Point Crater off Maine & Mass.
  David Kring of the Lunar and Planetary Laboratory at the University of Arizona is pessimistic and sees no conclusive evident
of an impact.  If Manzer and Abbott are correct, this crater is larger than Chicxulub. They are trying to determine the age
of the crater, but the erosional effects of ice ages have erased much of that evidence. Slim though any evidence might be,
Abbott is not giving up any time soon. Rather, she intends to look further south in the Martha's Vineyard area off Cape Cod.
There, she is hoping to find impact related rocks of the right age that might have been deposited after the glaciers retreated.

  Menzer believes the possible scenario of the event 65 million years ago was that the asteroid or comet broke up before
hitting Earth and pieces of the larger body slammed down in a rapid fire line of craters. The two scientists will search for
evidence this summer, to prove it was an impact event. Rock layers can then be used to age just when the impact happened.  (I)

Conclusion:
  The best available data on these craters (except Chesapeake) lump these events into a relatively short time frame in geologic
terms about 100,000 -300,000 years. If further research is done, it is found that there are at least 5 times in the past multiple
major impactors have collided with the earth and done global catastrophic damage, both to biodiversity and geological structures.
This occurrence tends to dovetail an astrophysical theory which states the solar system traveles through sparse & dense areas
of local galactic spiral arms/branches. This in effect causes perturbation of ‘comets’ in the Oort Belt and recently discovered
Kuiper Belt, which contain estimated millions of comet/asteroid sized bodies from the size of basketballs to large mountains.

After a million year trip past Jupiter, to be possibly perturbated and torn apart like the Shoemaker-Levy 9 comet (on it’s previous
pass near Jupiter before it collided with the same planet in 1994) and inward to our Sun, there is a chance for them to collide with
Earth. If an object is large enough it will leave eon old evidence for geologists to discover.  With the large demand for energy in
the form of hydrocarbons that is in current demand, oil companies all over the earth are searching for particular structures which
hold gas and oil. In these aforementioned craters many of these conditions are meant and gas and oil is being successful extracted.

  Certainly in the form of global extinction events, the effects of large impactors on humans has been negligible, so far.  But the
result of these collisions on the energy demands of a growing populous of ever increasing complexity, it could mean increased
discovery of energy resources. If exploration companies would correlate their efforts in the area of the 180 or so large impact
craters, ones that are large enough to cause the morphology that is conducive to the pooling of gas and oil.  And the discovery of
other obliviously present but so far unknown craters through geological and magnetic mapping, from space (Earth Resource
Satellites) and field surveys, perhaps new large gas and oil reserves could be located and exploited. If we can do it before the
‘next one’ hits.

References:
Fig 1: Post-impacts, polar orthographic mosaic of Jupiter in 2.0 micron infrared by the
5-m Hale Telescope at Mt. Palomar, July 1994 (Cornell University/Caltech/Air
& Space Museum).

Fig 2: Wikipedia The 24Km Boltysh Crater in the Ukraine, near Kiev
was discovered during oil prospecting.

Fig 3: Geological Survey of Canada 1992 Outcrop of strata crossing the Cretaceous-
Tertiary (K/T) boundary at Brazos River, Falls County, Texas   By Alan Hildebrand,

Fig 4:  Chesapeake Bay Bolide homepage. http://woodshole.er.usgs.gov/epubs/bolide/summary.html
Maintained by webmaster-woodshole@usgs.gov

Fig 5: A 0.32mm shocked quartz grain from intracrater breccia sample Y6 N14 of the
Chicxulub crater located. (Taken in cross-polarized light by Alan Hildebrand)

Fig 6: Geological Survey of Canada. The Chicxulub crater in Yucatan, with highlighted semicircle
of Cenotes or limestone sinkhole which border the southern outer ring of the crater.

Fig 7: BBC News  Friday, 18 March, 2005, 12:05 GMT
North Sea crater shows its scars
By Jonathan Amos  BBC News science reporter

Fig 8: Mare Orientale Credit: NASA, Lunar Orbiter 4
http://nssdc.gsfc.nasa.gov/planetary/lunar/lunarorb.html

Looking like a target ring bull's-eye, the Mare Orientale is one of the most striking large scale lunar features. Located
on the Moon's extreme western edge, this impact basin is unfortunately difficult to see from an earthbound perspective.
It is over 3 billion years old, about 600 miles across and was formed by the impact of an asteroid sized object. The collision
caused ripples in the lunar crust resulting in the three concentric circular features visible in this 1967 photograph made by
NASA's Lunar Orbiter 4. Molten lava from the Moon's interior flooded the impact site through the fractured crust creating
a mare.    APOD

Fig 9: Valhalla on Callisto From Voyager I 1979-03-06
http://nssdc.gsfc.nasa.gov/imgcat/html/object_page/vg1_p21287.html
 

Fig 10: 2003 Seattle Annual Meeting (November 2–5, 2003)
Paper No. 60-8  Presentation Time: 9:45 AM-10:00 AM
THE SHIVA CRATER: IMPLICATIONS FOR DECCAN VOLCANISM, INDIA-SEYCHELLES RIFTING, DINOSAUR EXTINCTION,
AND PETROLEUM ENTRAPMENT AT THE KT
CHATTERJEE, Sankar1, BOUNDARY GUVEN, Necip2, YOSHINOBU, Aaaron2, and DONOFRIO, Richard3, (1) Geosciences,
Texas Tech Univ, MS Box 41053, Lubbock, TX 79409-3191, sankar.chatterjee@ttu.edu, (2) Department of Geosciences,
Texas Tech Univ, Lubbock, TX 79409-1053, (3) Exploration and Development Geosciences, University of Oklahoma,
Norman, OK 73069

Fig 11: The Magnetic Field over Small Point, Maine
http://svs.gsfc.nasa.gov/vis/a000000/a002700/a002723/index.html
Possible Second Crater Linked to Dinosaur Extinction
http://starryskies.com/articles/2003/04/impact.html
From NASA Scientific Vis. Studio: Copyright © 1995 - 2004
Kathy Miles, Author, and Chuck Peters, Systems Administrator
k_miles+c_peters@200412.starryskies.net

F: http://pangea.stanford.edu/research/noble/newidria/node4.html

G:  DEEP IMPACT Shiva: Another K-T Impact?
http://www.spacedaily.com/news/deepimpact-04r.html
by Leslie Mullen for Astrobiology Magazine  Moffett Field CA (SPX) Nov 04, 2004

H: Possible Second Crater Linked to Dinosaur Extinction
http://starryskies.com/articles/2003/04/impact.html

I: Kathy Miles, Author, and Chuck Peters, Systems Administrator
http://svs.gsfc.nasa.gov/vis/a000000/a002700/a002723/index.html
k_miles+c_peters@200412.starryskies.net
Copyright © 1995 - 2004                                                                              More Asteroid Info?
The Magnetic Field over Small Point, Maine
From NASA Scientific Vis. Studio  Submit a comment or teaching tip
North American Magnetic Anomaly Group (NAMAG)    scale 1:5000
compilation and geologic mapping applications of the new digital
magnetic anomaly database and map of North America Geol. Soc. Am.                      TjT