During the several months after
publishing the initial version of this book, I have encountered several items
that require additional exploration, clarification or revision. The first six
appendices deal with the major items of this nature. Appendix VII will deal
with the remainder of these items. The items covered in this appendix are:
1. SIDESPIN What happens when
the angle of an impact is off to the side of a full diameter hit?
2. STATISTICAL JUSTIFICATION OF
CONTINENTAL UPLIFT What are the odds of having all of these old craters
only showing up in old continents and not in the new land areas of newly
uplifted continents? A statistical analysis of the crater data.
3. OTHER POSSIBLE IMPACT, LIP &
A. Hudson Bay & The Kerguelen
B. The Columbia River LIP & The
4. GRAVITY AS A CONTAINMENT VESSEL -- A
more in-depth analysis of how gravity contains the effects of an impact at the
5. CRATONS Reviewing the lack of
examples of stand-alone cratons from the early earth period.
6. THE CARIBBEAN LARGE IGNEOUS
DETAILS ON THE REVISIONS
When writing about the location of the
antipodal hotspot (and the consequent huge area of flood basalt lava) in
relation to an uplifted continent, I noted that the hotspot would be located
below the center of the main blob area of the new continent.
This location would be the result of
the strong rotational momentum of the impact pushing the primary uplifting
force beyond the antipodal hotspot point.
However, this scenario does not explain
the fact that, in two of the easily identifiable instances of hotspot location
(Siberia and India), the hotspot is located off to one side of the new
continent. Why would this happen?
The easiest way to characterize this
phenomenon is to call it sidespin. It is the result of the impact
object hitting the earth in such a way that the center line of its force does
not go around the largest arc that is possible
it does not trace the
largest cross-section that it could.
When an object hits the earth, there
are really two different angles involved. I will call these angles the vertical
angle and the cross-sectional angle.
A. VERTICAL ANGLE This angle is
the easiest to understand. This angle tells us how close to perpendicular the
impact was. A rare zero degree impact would produce no tail during a
continental uplift. A 45 degree impact would produce a long tail. A 70 degree
impact would likely ricochet off the atmosphere and leave few reminders of its
B. CROSS-SECTIONAL ANGLE This
angle is more difficult to explain. It not only tells us which direction the
impact was coming from, but it also tells us how dead center this hit was.
Perhaps an example will help.
Lets suppose that a really big impact occurs exactly at the North Pole at
a 45 degree vertical angle. Lets suppose that the centerline of the force
of the impact travels directly down the zero degree line of longitude and
passes underneath Greenwich, England.
In this case, the hit would be dead
center. The centerline of the force would pass through the largest
cross-section of the earth that is possible.
However, most hits are not going to be
dead center. There will be a cross-sectional angle away from dead center.
To continue the same example, this time
the impact would again come in at a 45 degree angle to vertical, but it will
have a cross-sectional angle away from dead center. Therefore, if we are
starting at the North Pole, this means that the centerline of the impact force
will cross some longitudinal lines and that the centerline of impact force will
be directed at some part of the earth that not the South Pole (a dead center
hit on the North Pole would see its centerline of force directed at the South
An off center cross-sectional angle
will result in the continent being off center in relation to the antipodal
hotspot. The hotspot will be located away from the side of the energy movement
of the blob.
2. STATISTICAL JUSTIFICATION OF
The theory of continental uplift at the
antipode of really big impacts implies that often there is new continental land
created from what used to be seabed.
In the last 250 million years, this
would be true in Siberia, much of South America (eastern South America was
broken away from Africa), Western Antarctica, Eastern North America (the
western part of it) and northern India (southern India was ripped out of the
Old Australian continents upper tail).
If the theory of antipodal continental
uplift is correct, then this new land should not contain any new craters that
predate its existence (it is possible that there were some old seabed craters,
but we should be able to identify them as such).
We know that there are a number of
older craters on the older continents. These include North America, Asia
(without Siberia), Europe and Australia (both Western Antarctica and Eastern
Antarctica are too hard to explore for these features).
As a percentage of total unsubmerged
land that can be examined for old impact sites, the newly uplifted continental
land might represent about 20%.
Looking at the Wikipedia chart of dated
impact craters of 20 km in diameter or more, there are 17 that are more that
250 million years old. 17 None of these craters are located in the
newly uplifted continental land.
The possibility that this distribution
of old craters just happened to miss these newly uplifted land areas (and that
this land was not really newly uplifted land) is small. The probability is 0.8
to the 17th power, or 2.3%. In other words, the table of large impacts tells us
that the possibility that the grouping of all the old craters outside of the
newly uplifted land has less than a 3% chance of being a random event.
Actually, the random chance level could
be shown to be significantly lower than 3% if we were to do some really
complicated stratification of the data so that we could include newer impacts
and the newer dates for India and South America.
In any case, there are no
contraindications for any of this land that is supposed to be uplifted. And
there is a significantly less than 3% chance that this uplifted land has no old
craters just due to random luck.
If the newly uplifted land was not
created through the process of continental uplift at the antipode of a very big
impact, then where did it come from?
3. OTHER POSSIBLE IMPACT, LIP &
Self and Rampino propose several Large
Igneous Provinces (LIPs) that should be investigated further.
With the exception of the CAMP, I look
at LIPs as the likely initial location of a hotspot that is antipodal to a
large impact. There are two of these that cry out for further investigation.
A. The Kerguelen Plateau
B. The Columbia River LIP THE KERGUELEN
The Kerguelen Plateau is a LIP that is
located just to the north of Antarctica and at approximately the same longitude
The hotspot beneath the Kerguelen
Plateau has been moving from the southwest to the northeast. The earliest
activity was around 120 MYA. The most recent activity in the northeast is
around 35 MYA. 78,79,80
While none of the sources cited above
lists an antipodal impact as a possible cause of the hotspot (should we be
surprised?), I believe an antipodal hotspot is the cause.
Furthermore, I believe that there is a
telltale physical feature that was located antipodal to the hotspots
beginning location 120 MYA. This feature is Hudson Bay in Canada.
The shape of Hudson Bay is strikingly
reminiscent of the shape of the Gulf of Mexico and the Yucatan Peninsula.
Others have looked at the rounded area
near the bottom of the bay and have found no sign of a crater. However, the
Gulf of Mexico does not have a crater near its rounded areas. The Chicxulub
crater is at the top of the thumb.
I suspect that there is a crater near
the top of Hudson Bay on one side or the other that relates to the Kerguelen
COLUMBIA RIVER LIP
The Columbia River LIP is located in
and near Oregon and Washington State. It occurred about 16 MYA.
I view this LIP as the large initial
eruption of a hotspot. However, I believe that the hotspot involved is the
Yellowstone hotspot, the second biggest super volcano in the world.
The Columbia River LIP does not match
up with the path of the Yellowstone hotspot. It is too far to the north.
However, if the original hotspot happened to be located under the heavy weight
of the Rocky Mountains, the basalt lava flows could have leaked out to the
north, rather than coming up right at the antipode.
I believe that if someone does the
research, they will find a large crater in the South Pacific antipodal to the
16 MYA extrapolated position of the Yellowstone hotspot.
4. GRAVITY AS A CONTAINMENT VESSEL
When I initially wrote about gravity
acting as a containment vessel, I did not go into detail. I believe that I need
to go into greater detail.
When we think about the impact effects
of a bullet hitting a watermelon, we dont consider the effect of gravity
acting as a containment vessel. The reason for this is the fact that a
watermelon has a virtually negligible gravitational field. A bullet will blow
the watermelon apart. There will be no gravitational effect from the mass of
The planet Earth is an entirely
different story. The effect of gravity from the mass of the Earth is huge.
When an object hits the Earth, the
effect at the antipode is very much constricted by gravity (unlike a bullet
hitting a watermelon, where everything just flies apart).
Gravity affects the results of the
impact at the antipode in the following ways:
A. Gravity adds tremendous downwards
pressure to the crust of the lithosphere, meaning that it will take a
tremendous amount of force to overcome both the force of gravity and the shear
strength of the rock in the lithosphere. For this reason, even big impacts can
usually only cause magmatic outflows at the weakened antipode, itself.
B. Gravity limits the extent of any
continental uplift. If a really big impact has enough force to uplift a
continent, gravity will keep operating on this continent as it rises up. As the
continent rises, the pressure is partially relieved. When the force of gravity
equals the diminished pressure of uplifting, the uplifting will stop. The shear
strength of the crust keeps the surface of the continent together.
If the impact force that is
transferred to the antipode is great enough to completely overcome both the
force of gravity and the shear strength of the lithosphere, then the antipodal
area will be blown into orbit (or even space if the force is extreme).
In the past 500 million years, we have
seen no impacts that could completely overcome both the force of gravity and
the shear strength of the lithosphere.
C. Gravity sets strict limits on the
magmatic activity, once the initial conditions have been settled. The
combination of the shear strength of the lithosphere and the force of gravity
will limit whatever happens next. And what happens next is magmatic activity at
the antipode. Gravity and the shear strength of the lithosphere will not allow
any more uplifting or expansion of the continents size after the initial
conditions have been settled. The only question left is how much magma will
When I first wrote about cratons last
year, I thought that there might still be independent, small cratons that had
been uplifted in the early days of the Earth (when the lithosphere was thinner
and easier to shear) that could be found in parts of todays oceans. I
listed the Kerguelen Plateau as a candidate.
I now believe that all of the cratons
from the early Earth may be already conglomerated into existing continents, or,
alternatively, subducted underneath them. This does not rule out the
possibility of an independent early-Earth craton turning up on the seafloor
somewhere, but I now consider this scenario to be unlikely.
The Kerguelen Plateau dates from 120
35 MYA. Zealandia goes back farther into time, but doesn't even reach
I conclude that most or all
freestanding cratons are the result of more recent magmatic events. 17
78, 79, 80, 103 pg 4
6. THE CARIBBEAN LARGE IGNEOUS
After putting together the scenario for
South America and then North America, I realized that the Caribbean LIP (Large
Igneous Province) could be explained, also. I had originally believed that this
explanation was beyond the information that I possessed.
The Caribbean Plate sits between the
North American Plate and the South American Plate. The Caribbean Plate is awash
with volcanism, which is called the Caribbean LIP.
There is significant controversy
surrounding the formation of the Caribbean LIP and its unusual turning
movement. One theory says that the region was formed over the Galapagos hotspot
and moved to its present location. Another theory says that the Caribbean Plate
and its LIP is the result of interaction with North America and South America,
although the mechanism is rather fuzzy 103 .
An analysis of the timing involved
helps to clarify the situation. While the LIP was formed approximately 139 MYA
to 69 MYA 104 , the dominant phase of this activity occurred 94 MYA
to 85 MYA 105 .
When we combine this information with
the fact that the New England Seamount Chain stopped 82 MYA and the Laramide
Orogeny (Rocky Mountain building) began 80 MYA to 70 MYA (see Appendix IV), a
mechanism becomes clearer.
The fact that the new Eastern North
American Continent was pulling away to the north and the west since irts
inception 202 MYA, would have led to an ocean floor spreading at its southern
132 MYA, the uplift of the South
American Continent would have absorbed some of the older volcanic output in its
Amazonas craton LIP (see Appendix III).
Subsequent volcanic output from
spreading would accrete to an area north of South America, and, because South
America was moving west, this area could be twisted into its own plate,
especially when the Eastern North American started to move in a different
direction around 80 MYA (see Appendix IV).
Somewhere around 80 MYA, the Eastern
North American Plate encountered the tail of the north and westward moving tail
end of the Siberian Plate and rotated clockwise, bringing the tail of the
Eastern North American Continent somewhat to the south, gradually killing the
ocean floor spreading and then twisting (and possibly creating) the Caribbean
The Chicxulub impact 65 MYA would have
augmented this North American move to the South, firmly ending the Caribbean
LIP formation. More movement to the south by the Eastern North American
Continent would have occurred 35 MYA due to the Chesapeake Bay impact (see
Appendix IV), causing more rotational movement by the Caribbean Plate.