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CHAPTER 2.3
PIECING TOGETHER THE "SMOKING
GUN"
The previous chapter paints the picture of what
happened at the antipode of the Chicxulub impact 65 MYA and how the evidence
for this story is laid out in the geological features that we see today.
The full version of Ben's Antipodal Impact Theory says that, in order
to have a major extinction, a cosmic impact has to be able to transfer enough
force to uplift at least a small continent near the antipode of the impact site
and to create aggressive and persistent volcanism at the antipode.
The
aggressive, persistent and explosive volcanism at the antipode of the cosmic
impact would be the main killer of life on earth, producing centuries of soot,
ash and noxious gases, which block sunlight would lead to a massive ice age.
However, both the impact (earthquakes, mega-tsunamis, atmospheric firestorms
and sun-blocking ejecta) and the uplift of a continent (mega-mega-tsunamis)
would start the process off with a bang.
EXPECTED GEOLOGICAL FEATURES
At this point, we can piece together the geological features that we would
expect to find in the aftermath of such a devastating event. These features
(which are fully in evidence in the case of the Chicxulub impact) are:
1. A Big Impact Crater — The size of the
crater (rather than the size of the impact object ... a deep water impact can
significantly blunt the force of the impact on the lithosphere and the mantle)
is directly related to the amount of energy that is transferred to the
lithosphere and the mantle. I estimate that the 170 km diameter of the
Chicxulub crater is at the mid-range of the size needed to uplift a continent
and cause a major extinction. The 90 km diameter Chesapeake Bay crater did NOT
coincide with a major extinction 35.5 MYA, nor did it uplift a continent (but
it did raise up mountains in eastern Australia).
2. A Large and
Persistent Antipodal Hotspot with Massive Lava Flows for Tens of Thousands of
Years — The antipodal hotspot that created the Deccan traps erupted
aggressively and persistently for 100,000 years and continued with major force
for up to a million years after that. Except in the rare event of a perfectly
vertical impact, we would expect this hotspot to move in the direction dictated
by the magma under the uplifted continent. Because the hotspot must cut through
the lithosphere like a plasma torch as it moves forward, we would expect it to
lag behind the path of the continent as described in the Baseball Theory of
Tandem Movement.
3. An Uplifted Continent — We would expect to see
an uplifted continent (which includes the antipodal hotspot somewhere in its
tail) in the shape of "a blob with a tail", with the tail pointing back to the
impact site. This newly defined continental tectonic mass can have some (or a
lot or all) mafic oceanic plate material as part of the mass. The mafic oceanic
plate portion of this new tectonic plate will be uplifted somewhat and it will
then settle back down, unless it is part of the forward moving edge of the new
continental mass, in which case, it will force its neighboring oceanic plate to
subduct beneath it (as occurred with India). We would expect to
see the continent imbued with forward motion by the magma beneath it. In the
case of the Chicxulub impact, the uplifted Indian continent was created in the
shape of a "blob with a tail" and it moved in the northwest direction dictated
by the transferred rotational energy of the magma beneath it.
EVIDENCE OF THE SMOKING GUN
So, when we are looking for evidence of a "smoking gun" for a cosmic impact
related to a possible major extinction event, we would expect to see:
1. CRATER — A crater that is greater than
90 km in diameter.
2. HOTSPOT — Evidence of a massive antipodal
hotspot that spewed-forth huge amounts of lava.
3. BLOB AND A TAIL
— Evidence of an uplifted continent in the shape of a "blob with a tail",
with the initial antipodal hotspot located somewhere within the tail.
4. CONTINENTAL MOVEMENT — Evidence of movement of the new
continent in the direction dictated by the forward rotational energy of the
mantle underneath it (the forward rotational energy being created by the angle
of the impact and adjusted by "Sidespin" ... defined at the end of this chapter
).
5. TANDEM MOVEMENT — Evidence of the hotspot moving in the same
general direction as the continent, but not moving as fast. All
of these five characteristics of the expected "smoking gun" of a major
extinction event are present in the case of the Chicxulub impact.
However, even though these factors are in evidence, we can see that it
has not been easy to actually figure them out. This book represents the first
time that anyone has been able to piece the evidence together.
The
Chicxulub impact is the most recent of the major extinctions. This impact has
left behind the clearest evidence of what happened because the evidence is much
more recent than the evidence from previous major extinction events. The
details of the other extinction events are going to be significantly more
difficult to piece together. But at least we know what we are looking for.
SIDESPIN
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
visit.
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. Let’s suppose that a really big impact occurs exactly at the
North Pole at a 45 degree vertical angle. Let’s 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 Pole).
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.
ACTUAL IMPACT SCENARIOS
The
next several chapters will deal with scenarios for continental tectonic plates
that have been created in the last 250 million years. Each chapter will outline
the evidence for a "smoking gun" for that continent's creation.
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