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CHAPTER 1.3 BEN'S ANTIPODAL IMPACT THEORY:
A THEORY OF ANTIPODAL IMPACT EFFECTS
Now that we have
reviewed some of the relevant features of the Standard Theory, it is time to
take a look at Ben's Antipodal Impact Theory, a new theory of antipodal impact
effects. In section I of this book, we will consider only the "safe,
conservative" version of Ben's Antipodal Impact Theory.
This new theory
views the basic structure of the Earth in the same way as the Standard Theory.
This new theory also agrees with the basic designation of the four major layers
of the earth the crust, the mantle, the outer core and the inner core.
However, Ben's Antipodal Impact Theory disagrees with the Standard
Theory about some aspects of ALL of the other features discussed in the
previous chapter. This new theory especially disagrees with the Standard Theory
about the effects of a large impact at the antipode of the impact site. The
Standard Theory says that the effects at the antipode would be minimal, as long
as the lithosphere is not breached at the impact site. Ben's Antipodal Impact
Theory says that the effects at the antipode can vary from significant to
catastrophic.
Let's look at how Ben's Antipodal Impact Theory views the
results of a major cosmic impact.
The key ingredient to Ben's Antipodal
Impact Theory is the idea that big cosmic impacts produce profound effects at
the antipode of the initial impact site.
Specifically, I propose that a
large enough impact will produce a volcanic hotspot at or near the site of the
antipode of that impact. Furthermore, I propose that this hotspot will move in
a specific direction, related to the angle of its off-center impact.
Very few impacts are absolutely straight on. Most big impacts are in
the range of 30 degrees to 45 degrees to vertical (beyond 45 degrees, there is
much more chance of the impact object glancing off as it hits the atmosphere).
The off-center nature of an impact will determine how the directional energy is
imparted to the hotspot. Because the impact is usually off-center, the energy
antipode of an impact is usually not exactly at the site of the physical
antipode ... close, but not exactly at the same location.
The mechanism
that allows pressure energy to form a mantle plume is based primarily upon the
changes in the behavior of materials when they are subjected to extreme
vibration. I believe that there is a certain threshhold level of extreme
vibration and duration of that extreme vibration that allows, on a temporary
basis, for the virtual elimination of the power of friction.
Once this
frictional release threshold has been reached, then a mostly impermeable
region, such as the Earth's mantle, can be breached and rapidly penetrated by
hot liquid olivine under great pressure.
LARGE IMPACTS & CONTEMPORANEOUS ANTIPODAL
MANTLE PLUMES -- A MECHANISM FOR CAUSE AND EFFECT
Current mantle plume theory claims that pockets of liquid
rock at the core boundary rise towards the surface in the form of a mantle
plume. Because the mantle is resistant to movement, this plume can only rise at
a rate of approximately one inch per year. At this rate, it would take over 100
million years for a mantle plume to reach the underside of the lithosphere.
Therefore, according to current mantle plume theory, there is no
possibility of a large impact causing a contemporaneous mantle plume that would
reach the underside of the lithosphere.
So, if the mantle is so
resistant to penetration, how do I propose that a mantle plume could penetrate
it in such short order? The answer is something that I call the Frictional
Release Threshold (FRT).
What I am saying is that under any normal
circumstances, a plume or anything else will not move through the mantle at a
speed that is faster than about one inch per year. However, when extreme
vibration is involved, things can change dramatically. And extreme vibration is
exactly what a very large impact brings to the table.
During my years
in the cold formed fastener business, I saw the effects of vibration in
dramatic ways. The company that I worked for, Rockford Products, had an
applications engineering lab with many different types of test equipment,
including a vibration test machine.
Vibration is important in the study
of screw and bolt applications because, unless some kind of locking device is
used, the only reason that a joint will retain its clamp load is friction.
As a rule of thumb, when a bolt is tightened in a joint, 50% of the
torque is used to overcome the friction between the head of the bolt and the
joint surface, 40% of the torque is used to overcome the friction in the
threads and only 10% of the torque is actually used to increase the clamp load.
Vibration can cause momentary loss of friction. Extreme vibration can
cause the friction to virtually vanish.
The vibration test machine at
Rockford Products showed how vibration could reduce the effects of friction
dramatically. It was kind of fun to torque up a bolt to full clamp load and
then turn the vibration tester on to the maximum setting. The bolt would
unscrew itself at a speed that was easily visible to the naked eye. Most
vibrational loss of clamp load in real life happens much more gradually.
The vibration test machine was extreme enough that it had to be mounted
on rubber blocks so that it didn't shake the lab apart. But, even though the
vibration test machine created an extreme vibrational environment for
industrial testing, it would pale in comparison to the vibration felt by the
Earth's mantle immediately after a very large impact. A significant portion of
two million H-bombs of energy (in the case of the Chicxulub impact) would be
converted to shear waves that would ping pong between the Earth's lithosphere
and the Earth's outer core (shear waves can't penetrate either the outer core
or the inner core). The mantle would be continuously subjected to the most
extreme shear imaginable, until the waves dissipated.
This vibration
effect is particularly important because the Earth's mantle is held in place
(and slows the movement of anything through it) by friction and friction alone.
Friction can be a powerful force. We depend upon it to hold many things
together. But vibration can make a huge difference. A small amount of vibration
may not do much, but once once the vibration reaches a certain threshold, the
FRT, it can reduce or even eliminate the effects of friction. Later, when
vibration later falls back below the FRT, friction takes back its power and
everything returns to the status quo.
I am proposing that very large
impacts, those that create impact craters of 85 km in diameter or larger, can
produce shear waves in the mantle that are powerful enough that they will cause
the vibration in the mantle to rise above the FRT for long enough for the
pressure waves to push a mantle plume through the mantle to the underside of
the Earth's lithosphere.
I also propose that there is a layer of liquid
rock between the liquid core and the mantle. I propose that this liquid rock
has a relatively high concentration of olivine. I will call this layer the
liquid olivine layer. The Standard Theory proposes that there is liquid olivine
here, also, but maybe just pockets of liquid olivine.134 In my
model, the intense pressure waves compress and move this liquid olivine layer
around the Earth's core towards the interior physical antipode of the impact.
The off-center pressure waves would meet at the physical antipode, with the
stronger forward pressure waves over-topping the backward pressure waves,
causing the plume to center slightly beyond and to the side of the physical
antipode (at the energy antipode).
IT'S HOTTER THAN YOU THINK
According to an article in
the January/February, 2014 issue of Discover Magazine, a European research team
has determined that the core of the Earth has a temperature of approximately
11,000°F (6000°C), instead of 9,000°F, as previously believed. The
liquid outer core of the Earth is now estimated to have a temperature of
3800°C, while the lower mantle checks in at 3000°C. It is reasonable to
assume that the area of the mantle that is right next to the outer core would
pick up at least some of this 800°C heat difference, enough to liquify a
small layer of mantle.
If this liquid mantle layer were only one mile
thick, then, using the formula for the volume of a sphere (4/3 Pi [r cubed]),
we can calculate the material volume of this liquid layer. The calculation
would be (4/3 Pi [2171 cubed]) minus (4/3 Pi [2170 cubed]). This reduces to
(42,861,561,540) minus (42,802,360,500). This equals 59,201,040 cubic miles of
material found in a one mile layer surrounding the Earth's liquid outer core.
The total amount of volcanic material expelled from the Deccan traps
has been calculated to be 27,000 cubic miles of material. While 27,000 cubic
miles of material is a huge amount of material, it is less than 1/20 of one
percent of the amount contained in a one mile layer that surrounds the Earth's
outer liquid core. In other words, even a relatively small band of liquid
mantle surrounding the outer core would contain more than 2000 times as much
material as would be needed to create all of the Deccan traps.
THE LIQUID CORE GETS
INVOLVED
But this is just the
beginning of the story. When I first examined the possibilities of liquid from
the interior shooting up to the underside of the lithosphere, I thought in
terms of liquid mantle material only. My reading had described olivine material
from deep in the mantle as being the volcanic result. Therefore, I thought only
in those terms.
However, I now realize that the liquid core, containing
a much, much larger amount of material than just a narrow layer of liquid
mantle, is a big player, as well. The liquid material in the liquid core would
be affected by the intense pressure waves of a large impact, too.
As
both the liquid core and the much smaller layer of liquid mantle are pushed by
the pressure waves in the direction of the energy antipode, the lighter
material (the mantle) will rise first.
The pressure waves will
penetrate the liquid core, whereas the shear waves will not. This means that
the liquid core will be impacted by the pressure waves and will distend towards
the energy antipode, just as the small layer of liquid mantle will do. This
also means that, in the case of a really large impact, there would be so much
material moving upward that some of liquid core would be included in the mantle
plume that rises to the surface. In this case, we would expect to see nickel
and even iron in the volcanic material ... which we do see in the Deccan traps,
the Siberian traps and other Large Igneous Provinces (LIPs). One would expect
that the lightest material (the mantle) would dominate the first eruptions (and
in the case of small plumes, almost all of the material might be mantle
material). However, in the case of large plumes, subsequent material might be a
mix of both mantle and outer core.
The evidence supports this theory.
Wikipedia and several other sources note that LIPs are associated with economic
concentrations of copper-nickel and iron. The Siberian traps are listed as the
largest source of volcanic nickel on the planet.
CREATING A SEMI-PERMANENT SPINEL LAVA
TUBE
An interesting sidelight involves the longevity of
these mantle plumes. A person might wonder why the plume tubes wouldn't
collapse rather quickly, instead of leading to hotspots that last for tens and
even hundreds of millions of years.
A livescience article by Tia Ghose
entitled "Earth's Biggest Deep Earthquake Still a Mystery," notes that olivine,
under great pressure, can transform into spinel, and that this transformation
is irreversible. Spinel is a hard, tough substance that might well be acting as
a sheath around the liquid olivine that escaped the extreme pressure waves by
fleeing to the surface. The olivine that couldn't escape along the walls may
have been transformed into a sheath of spinel. 127
SUMMARIZING THE THEORIES
The
Standard Theory hypothesizes pockets of molten olivine next to the core that
gradually make their way to the surface in the form of mantle plumes at a rate
of about one inch per year. The Standard Theory sees no relationship between
very large impacts and the creation of mantle plumes.
My theory
hypothesizes a layer of molten olivine next to the core. A very large impact
will cause pressure waves that will then cause the liquid olivine to converge
at the interior physical antipode at the mantle/core boundary. If the shear
waves are strong enough for long enough, they will cause shaking in the mantle
that will reach levels beyond the FRT. Once the material in the mantle is
shaken beyond the FRT, the directionally pressured liquid olivine will be
forced upward to the underside of the Earth's lithosphere in the form of a
mantle plume. The forward over-topping energy transferred from the off-center
impact will result in an energy antipode at the surface that is slightly beyond
and to the side of the physical antipode.
THREE ANALOGOUS EXAMPLES
Although I do not know of any example in geology that is completely
analogous to the method of mantle plume creation that I propose, there are
three examples in nature and industry that share significant similarities.
These examples may be helpful in picturing the process and understanding that
this type of situation is not unprecedented.
The key to understanding
the mechanism is to realize that friction is the only thing that restricts
normal movement in the Earth's mantle to about one inch per year. Once the the
friction has been released, there is nothing to stop the pressurized olivine
from shooting upwards to the bottom of the Earth's lithsphere. Since friction
is the only retarding force at work here, it is only a question of how much
extreme vibration it will take to cause the friction to be completely
compromised. And, in the case of very large impacts, we can invoke the words of
that eminent musical geologist, Elvis Presley, who said, "There's a whole lotta
shakin' goin' on ... woooo!" (It's always good to bring in the King of Rock
when analyzing things of a geological nature.)
WET CEMENT
The first example
of a roughly analogous situation is that of wet cement. The consistency of the
Earth's mantle is often compared to wet cement. It is difficult to move an
object through wet cement, just as it is hard to move an object through the
Earth's mantle.
However, vibration changes everything. In construction,
vibrating rods (mostly used to vibrate air bubbles out of wet cement) are used
to easily pierce wet cement. An article entitled "Vibration & Re-vibration"
by Amr Mohamed Ismail states:
"Vibration of fresh concrete reduces its internal
shear strength and enables the concrete to temporarily liquify. facilitating
the consolidation process. Once the vibration stops, its liquid flow subsides.
137pg4
Another variation of this
theme involves earthquakes in saturated soils. The earthquake vibrations can
cause soil liquifaction, allowing buildings to actually sink into the soil.
Extreme vibration would allow nearly complete release of friction.
The
wet cement analogy is almost completely analogous, except for the the fact that
a significant amount of water is involved in the wet cement and saturated soil,
whereas there is likely to be much less water in the mantle. Therefore the FRT
would likely be much higher in the mantle.
GLASS
Another near analogy is
that of glass. Like Earth's mantle, glass is frictionally bound together, not
chemically bound together.
In this case, I will use temperature as a
stand-in for vibration when looking at glass. I could even argue that, on an
atomic scale, temperature and vibration are two sides of the same coin. But,
clearly, temperature is not actually the same as vibration and that is where
the analogy separates.
However, the glass analogy allows us to
visualize a substance that is rigid at temperatures up to 850 degrees
(depending upon the type of glass). As the temperature rises, the glass
undergoes reversible changes from slumping to viscous to liquid as the
temperature exceeds 2400 degrees. Above 2400 degrees (again, depending upon the
type of glass) there is virtually no resistance to penetration.
As the
temperature is brought back down to below 800 degrees, the glass goes through
these same stages in reverse, ending up as a solid, unmoveable slab.
SPRITES
A third near analogy
is that of sprites, which are a recently discovered and photographed phenomenon
in the upper atmosphere. During particularly intense thunderstorms, lightning
not only occurs from cloud-to-cloud and from cloud-to-ground, but also upwards
from cloud-to-ionosphere. A bolt (actually more of a spray) of
cloud-to-ionosphere lightning is called a sprite.
Of particular
interest is the fact that sprites only occur during very, very intense
thunderstorms, and since they only occur between the tops of clouds and the
ionosphere, they are very hard to photograph. If you photograph only the tops
of normal thunderstorms, you would likely never see a sprite.
I would
argue that the very high threshold of energy required to produce a sprite is
directly analogous to the high level of intense pressure waves and shear waves
required to produce a mantle plume during an impact. Smaller impacts just won't
reach the threshold, just as normal thunderstorms won't produce sprites.
However, statistical analysis (see next chapter) reveals that, in the last 100
million years, all four impacts that produced craters of 85 km in diameter or
more did reach the threshold and did produce mantle plumes.
This sprite
analogy is quite comparable to the mechanism for producing mantle plumes,
except for the fact that sprites are electrical phenomena, whereas mantle
plumes are physical phenomena. One other interesting point about sprites is the
fact that some of the largest sprites spread out along the bottom of the
ionosphere in almost the same shape as a mantle plume head when it is forced up
against the bottom of the Earth's lithosphere.
RESONANT SONIC DRILLING
There
is also the fact that industrial drilling has already developed a drilling
method that uses vibration to do the job. An article entitled "the Resonant
Sonic Drilling Method: An Innovative Technology for Environmental Restoration
Programs" by Jeffrey C. Barrow shows a picture of a rock with a hole in it,
with the following caption: "Four-inch diameter sonic core hole drilled through
a large granite boulder." 135pg157
The article describes the
process of resonant sonic drilling as follows:
"The method uses the natural elasticity and
inertial properties of a steel pipe to allow wave propagation that will make
the drill pipe expand and contract due to these waves. These characteristics,
coupled with the effects of bringing the pipe into resonance, are what allows
the drill pipe to penetrate through virgin earth formations with little
resistance, often like a knife through soft butter."
135pg155
An information sheet from Terrasonic
International describes the key to the sonic drilling process as follows:
"This intense vibration causes a very thin layer
of soil directly around the drill rods to fluidize."
136
Although resonant sonic drilling employs a
very precise mechanism (which would not be the case in the massive vibrations
from a very large impact), the fact that the vibrations from a very large
impact would be hugely more massive would likely make up for the lack of
precise focus. Also important would be the intense pressure waves pushing the
liquid olivine layer towards the surface.
HIGH PRESSURE SHOCK WAVES
The
purpose of this section is to offer further explanation of how the shock impact
of a large cosmic object can cause directed pressure in the liquid inner core
and the small liquid band in the lower mantle of the Earth, leading to a mantle
plume with directed motion.
Some readers might well wonder why the
pressure felt in a liquid would not end up equally distributed tom all points,
as might occur in a hydraulic cylinder. Well, in the long run, all the pressure
would distribute equally. However, we are not looking at the long run. We are
looking at what would happen in the early stages, just after the impact, when
the mantle would be permeable, due to extreme vibration.
When a large
cosmic object impacts the Earth in a non-deep ocean area of the planet, the
impact will cause more than just pressure waves. It will also cause high
pressure shock waves.
Most of us have seen these high pressure shock
waves illustrated as part of the result of an atomic blast. The blast blows
trees over and it blows houses apart. High pressure shock waves can be
significantly more powerful and penetrating than ordinary pressure waves.
The key to a powerful high pressure shock wave is the speed of the
impact object that is hitting the target. A very high speed makes a very big
difference. If the speed is below a certain threshold level, the impact object
will not produce a meaningful shock wave. If the speed is well below a certain
threshold level, the impact object will not produce a shock wave at all.
SHAPED
CHARGES
One way to
understand the effect of high pressure shock waves is to look at similar events
that occur in the military. The military uses something called a "shaped
charge" to direct an explosive blast in a focused direction, in order to create
a useful shock wave.
These shaped charges usually consist of a cone
shaped explosive charge with an interior cone shaped jacket. When the explosive
is set off, the explosive cone focuses the explosion on the metal interior cone
shaped jacket, forcing it to reshape itself into a semi-liquid jet that is
propelled with great force and high speed.
When this type of shaped
charge is used in a high explosive anti tank (HEAT) shell, it can be very
effective in piercing even heavy armor. As noted in an article on the
GlobalSecurity.org website, "Even a small 440 gram shaped charge explosive is
extremely destructive, and can penetrate 14 inches (35.6 cm) of armor."
The key to the destructive power of the shaped charge is the high speed
that it imparts to the penetrating object. The GlobalSecurity.org website
explains: "Full hydrodynamic behavior does not occur until the strike velocity
reaches several kilometers per second, such as occurs with shaped charge
munitions. At strike velocities less than about 1,150m/s penetration of metal
armor occurs mainly through the mechanism of plastic deformation. A typical
penetrator achieves a strike velocity around 1,500m/s to 1,700m/s, depending on
range, and therefore target effects generally exhibit both hydrodynamic
behavior and plastic deformation."
When the GlobalSecurity.org website
speaks of a typical strike velocity of 1,500m/s to 1,700m/s, this translates to
about 3,600 mph. Most cosmic impacts occur at speeds of 20,000 to 40,000 mph.
In other words, cosmic impacts have an order of magnitude more speed than is
needed to reach the high pressure shock wave threshold.
While a cosmic
impact is not a shaped charge explosion, it does contain the two primary
characteristics that are important to the shock wave effect. These two
characteristics are:
1. High Speed - The impact of a cosmic object will
easily reach the threshold needed to produce a punishing shock wave. Another
factor to consider in all of this is the fact that shock waves dissipate
relatively quickly.
2. Directed Motion - Although the impact will
"waste" considerable pressure energy off to the sides of the impact, there will
still be plenty of energy applied directly in front of the impact object. In
effect, a high speed cosmic impact can be viewed as a sloppy and inefficient
shaped charge, with the directed impact acting as a substitute for the focusing
device.
One other observation from GlobalSecurity.org is useful in our
understanding of this idea of high pressure shock waves, as exemplified by
shaped charges. The website says: "Shaped charge is indeed an extraordinary
phenomenon that is beyond the scale of normal physics, which explains why its
fundamental theoretical mechanism is by no means fully understood."
The
academic reader might wonder why I have chosen shaped charges as the closest
analogy to the high pressure shock wave caused by a cosmic impact. Why didn't I
merely rely on theoretical models of the physics of shock waves?
I have
chosen the shaped charge as the best analogy because it covers the primary
characteristics and because there is a long history of indisputable, actual
results in the real world. Furthermore, as noted in the previous quote from
GlobalSecurity.org, there are still questions as to the true nature of
theoretical shock wave models.
I will attempt to illustrate the nature
of this high pressure shock wave as it relates to the Chicxulub impact 65 MYA
in a series of illustrations at the end of this chapter.
PENETRATING IMPACTS
When I first realized that
energy from very large impacts might be transferred into the interior of the
Earth, I did not believe that these impacts necessarily broke through the
Earth's crust. I thought that, rather, the energy might be transferred to the
mantle in a way similar to the suspended steel balls of a Newton's cradle
creating a mostly linear transfer of the directional force of the
impact.
However, all of the models that I have read about suggest that
this kind of transfer would not occur. Rather, the impact force would ricochet
around the interior of the planet at all sorts of angles, producing an interior
force with no real focus at all.
The only way to have a truly focused
impact force in the Earth's interior would be to have the impact object
penetrate the Earth's crust and travel at least a considerable distance in the
mantle. This leads to two questions: First, is it realistically possible that a
very large impact object could penetrate the Earth's crust and continue its
journey into the mantle? And, second, is there any evidence that an impact
object actually did penetrate the Earth's crust?
COULD A VERY LARGE IMPACT
OBJECT PENETRATE THE EARTH'S CRUST?
The key to transferring the directional energy of an impact
object to the Earth's interior is the ability to penetrate the Earth's crust.
Once the Earth's crust has been penetrated, the residual impact object will be
able to move through the mantle with relative ease, due to the vibrational
release of the normal friction as described in Chapter 1.3 of this book.
The question is: Could a very large impact object really penetrate the
Earth's crust or would it just make a big crater on the surface?
Perhaps the best way to explore the issue of penetration is to look at work
conducted by people who study penetration as part of their job - the U.S. Army.
The U.S. Army studies the parameters of penetration so that they can understand
how to penetrate armor and so that they can understand how to block the
penetration of armor.
On the one hand, the Earth's crust is not going
to have the same penetration resistance as armored steel plate. But, on the
other hand, if we can show that a very large impact object could penetrate the
Earth's crust even if it were made out of armored steel plate, then that same
object would certainly be capable of penetrating the ordinary rock of the
Earth's crust.
The military has developed special weapons to penetrate
armored plate. Specifically, they use a device called a "shaped charge" to
accomplish this penetration. Sometimes the shaped charge is placed inside a
landmine so that the force will be directed upwards into a truck or a tank.
Sometimes the shaped charge will be put in the front part of a missile or
rocket that is to be fired at a tank or other armored object.
Many of
us have seen war movies with a soldier firing a bozooka (now known as a 3.5
inch rocket launcher) at a tank, which is disabled by the impact. It is
actually the shaped charge in the nose of the rocket that penetrates the tank's
armor and kills the people inside.
So, how come we can't just fire a
bullet at the armored tank and achieve the same results?
The answer is
that an ordinary bullet is way too slow (and it is also too small). Even the
fastest bullets are too slow for the job.
The average rifle bullet
travels at about 1,700 mph initial velocity. Too slow.
The fastest
commercially available cartridge (Remmington .17) has a 3,000 mph initial
velocity. Still too slow.
A molten mass delivered by a shaped charge
travels at approximately 20,000 mph initial velocity. This speed is an order of
magnitude faster than the average rifle bullet. This ultra-high speed allows
the penetrator to penetrate as much as 700% of the diameter of the mass of the
penetrator. This is NOT too slow.
And, yet, the impact speed for most
asteroids hitting Earth is usually cited at 30,000 mph
even faster than
20,000 mph.
Therefore, if the Earth's crust were made of armored steel
plate and if an asteroid of six miles in diameter (the smallest listing for the
Chicxulub impactor) collided at 20,000 mph (only 2/3 of the usually cited
number), then we could expect that the asteroid could penetrate 42 miles of the
Earth's armored steel plate crust. Except that the Earth's crust is not made of
armored steel plate. Except that the asteroid was probably going 50% faster.
Except that the Earth's crust is from 4 to 40 miles thick, not 42 miles thick.
In other words, the Chicxulub object would have had lots more power and speed
than was needed to penetrate the Earth's crust. From the evidence seen in
antipodal hotspot mantle plumes, it appears that three other very large impacts
over the past 100 million years also managed to penetrate the Earth's crust
(see Chapter 1.4 of this book).
EVIDENCE OF
PENETRATION
The preceding
argument establishes the possibility of penetration of the Earth's crust by a
very large impact object. Now we need to see if there is any actual evidence of
penetration.
First, we can look at the "coincidence" of hotspot mantle
plumes occurring antipodal to the four largest impacts in the last 100 million
years, as detailed in Chapter 1.4 of this book.
But, while this
statistical evidence is impressive, there is even more impressive evidence.
This evidence consists of the improbable existence of Zealandia. 170, 171,
172, 173, 174, 175
ZEALANDIA
Somewhere between 60MYA and
70MYA, Zealandia was formed. Zealandia was a low lying hunk of land that was
about the size of Greenland and which included present-day New Zealand.
Zealandia was separated from from the Australian mainland by the Tasman
Sea. The undersea land of the Tasman Sea basin showed "stretch marks,"
indicating that this area of the ocean floor had been stretched out.
Therefore, a likely explanation for the formation of Zealandia would be
that the land had rifted away from Australia, just like Madagascar had rifted
away from Africa and Greenland had rifted away from North America. If the
existence of Zealandia were due a rifting away from Australia, then the rifting
process would have had to start about 10 million years earlier, in order to
allow time for the formation of the Tasman Sea.
Then the rifting
stopped about 60MYA and the land of Zealandia began to sink, leaving the vast
underwater plateau that exists today.
But why did it sink? Madagascar
didn't sink. Greenland didn't sink. And why did the rifting mysteriously stop?
AN ALTERNATIVE EXPLANATION
Well, maybe there is a
different explanation for Zealandia that fits the actual facts better.
The alternative explanation for the existence of Zealandia involves the
Chicxulub impact 66 MYA. Of the four impacts in the last 100 million years that
have been large enough to penetrate the Earth's crust and enter the mantle, the
Chicxulub impact was by far the largest. It dwarfed the other three.
If
the other three penetrators were able to make it through the crust and into the
mantle, the Chicxulub object would likely have had enough power to make it all
the way through the mantle, with enough residual power to affect the solid
crust from the inside when it finally came to rest. The point at which this
Chicxulub remnant would have impacted the opposite end of the Earth's crust
from the inside would be located to the south and east of the physical antipode
of the original impact (due to the angled original impact). In other words,
Zealandia would be right at the center of the area where we would expect this
attempt at an "exit wound" by the Chicxulub object.
The alternative
explanation for the existence of Zealandia goes like this:
1. The
Rangitata Orogeny from 142 MYA to 99 MYA formed the area around New Zealand,
itself. It had nothing to do with the larger area of Zealandia. This Rangitata
orogeny was the result of volcanism involving the hotspot mantle plume from the
Manicouigan impact, which occurred 212 MYA, but was mostly covered up by the
small continent of Western Antarctica as it moved to the south and west. The
hotspot was briefly uncovered as the Western Antarctic continent moved
counterclockwise due to the coriolis effect, while drifting south. After
marching across Eastern Antarctica, the hotspot is now located at Mount Erebus
in Western Antarctica (see Chapter 2.6 of this book).
2. Zealandia was
not split off from the continent of Australia in the manner of Madagascar and
Greenland. Rather, it was formed by uplift of material on the continental shelf
of Australia 66 MYA, when the Chicxulub penetrator attempted an "exit wound" in
that area. The "stretch marks" seen in the basin of the Tasman Sea resulted
from stretching as the neighboring land was forced upwards (not from being
pulled off to the side as part of a rift).
The uplift of Zealandia
would have created a large, lowlying area that would have had a tendency to
subside, once the original dramatic penetration pulse was over. The result was
almost the direct opposite of the rising of land in cases of glacial rebound,
when the compressive forces of tons of ice are removed. With the release of the
impact pressure, the land of Zealandia subsided over the millenia, but, as in
the case of glacial rebound, not to the same level as its original position.
During these millenia of subsidence, there were alternating instances of
glaciation (New Zealand and Zealania were even closer to the South Pole in the
past), which resulted in the carving up of the surface in a manner similar to
Greenland.
3. The Kaikoura Orogeny of 24 MYA to the present is the
result of volcanic activity at a weak point in the Earth's crust, that was left
by the Manicouigan hotspot plume. This activity has affected only New Zealand
and not the rest of greater Zealandia.
The alternative explanation for
Zealandia not only explains why the Zealandia plateau was formed in the first
place, but it also explains why it subsequently subsided. Furthermore, it
explains why the appearance of a rift exists and why it appeared to stop 60 MYA
(the reason - it wasn't ever actually rifting at all).
The fact that
this alternative explanation fits in almost exactly where the penetration
scenario expects that it would is a major bonus as far as corroboration of my
impact theory is concerned.
The point is that my theory explains the
evidence in a logical manner, whereas the current theory can offer no
explanation for the cessation of "rifting" 60 MYA nor the subsidence of
Zealandia subsequent to its creation
especially when such subsidence is
not found in other instances of major rifting events (Madagascar and
Greenland). 176, 177, 178, 179, 180
WHY SPEED AND SIZE MATTER
The previous section details
the reasons that the speed (or velocity) of an impact object matters. As
related in the test data of the U.S. Army, a projectile moving at 2,000 mph
will not penetrate serious armored steel plating. However, a projectile moving
at 20,000 mph will penetrate armored steel plating up to 700% of the diameter
of the penetrator.
But speed is only part of the equation, when it
comes to penetrating the Earth's crust. Size matters, too. Everything else
being equal, a more massive penetrator will be more effective than a less
massive penetrator. There are two reasons why this is so. These reasons are:
1. Better Mass to Impact Area Ratios - Everything else being equal, a
more massive penetrator will bring more mass per square mile of impact area to
the penetration attempt. Let's look at a really simple, easy-to-follow example
(simple, but not realistic
but the example will translate well to
realistic examples, without any complicated math). In this example, we will
assume that the small penetrator is shaped in the shape of a cube, with each
side dimension being one mile in length and that that the small penetrator will
hit the Earth flush on one of its square sides, creating a one square mile
penetration area with a mass of one cubic mile behind it. In this case, the
mass to impact area ratio would be 1:1.
So, what would happen if the
impact cube were ten miles on a side instead of one mile on a side? In this
case, the impact face would be 100 square miles (10 x 10), backed up by a mass
of 1000 cubic miles of material (10 x 10 x 10). The mass to impact area ratio
would be 10:1. Therefore, the larger penetrator would have ten times as much
momentum behind it on each square mile of impact area.
While virtually
no penetrator is going to be created in the shape of a cube, the cube example
is easy to illustrate and the math is easy to calculate in one's head. A more
logical example of a spherical penetrator would show the same kind of result,
but the math is not quite as simple.
The key to understanding why the
penetration ratio is better for more massive penetrators is realizing that the
impact area is a two dimensional feature (square miles), whereas the mass is a
three dimensional feature (cubic miles). Therefore, as a penetrator becomes
more massive, the impact area will increase as a function of the square of the
radius, whereas the mass will increase as a function of the cube of the radius
the mass increases more quickly than the area that it has to penetrate.
2. Better Size to Crust Depth Ratio - The second reason that size
matters is the fact that larger penetrators will have a better size to crust
depth ratio. The depth of the Earth's crust remains the same, regardless of the
size of the object that impacts it. Therefore, if a cosmic impactor could
penetrate more than 700% of its diameter in armored steel plate, then it makes
a big difference if the impactor is 1/4 of mile in diameter (which would
penetrate almost 2 miles or more) as compared to an impactor that was 10 miles
in diameter (which could penetrate at least 70 miles of the Earth's crust).
Since the Earth's crust has a definite depth of between 4 and 40 miles,
the smaller impactor almost certainly would not penetrate the Earth's crust,
whereas the larger impactor would almost certainly penetrate the Earth's crust
(Note: Virtually all of the places where the Earth's crust is only 4 miles
thick or close to that number, occur under miles of ocean, which provides a
huge amount of protection from penetrating impact due to the way that water
disperses a penetrating force.).
Size matters. It is not surprising
that only the four largest impacts of the past 100 million years have shown
clear signs of penetrating impact (see Chapter 1.4).
WHY DOES PENETRATION MATTER?
So, why are we spending so
much time examining the probability of penetrating impacts by very large impact
objects?
The reason is that a penetrating impact will deliver most of
its energy to the interior of the planet, rather than seeing that energy spread
along the surface and even slowing down or speeding up the rotation of the
Earth. A penetrating impact will have the energy necessary to create the
powerful interior pressure waves that can move liquid mantle material and
liquid core material into a focused mantle plume eruption. A penetrating impact
will have the energy necessary to produce prodigious interior shear waves that
will temporarily release the grip of friction on the mantle material and allow
a mantle plume to slice through it.
A penetrating impact will see most
of its impact energy transferred to the Earth's interior, just as a high speed
rifle bullet captured in ballistic jelly transfers its destructive energy to
the interior of that block of ballistic jelly.
OTHER "ATTEMPTED EXIT WOUND"
UPLIFTS
The uplift at
Zealandia in many ways resembles a bullet's attempt to create an exit wound
when the bullet is fired at an animal or a watermelon or any other object with
an outer shell and a softer interior.
If the bullet has sufficient
velocity, it will travel through the softer interior and exit out the other
side. The entrance wound is typically small
. about the size of the
bullet, itself. The exit wound is an entirely different matter. Depending upon
the speed, shape and composition of the bullet, the exit wound can be big,
bigger or huge.
The point is, the size of the exit wound will be at
least significantly larger than the size of the impact object, itself.
If, however, the bullet does not have
enough momentum to penetrate the exit area of the outer shell, the bullet can
cause a bulge at the "would be" exit point. Again, the size of the bulge can be
significally bigger than the size of the impact object, itself.
I have
written about the likelihood that Zealandia is the attempted exit wound of the
Chicxulub impact object. This assumption is based upon the idea that if normal
large impacts could penetrate the Earth's crust and cause mantle plumes, then a
really large impact object might well cause a bulge at an attempted exit wound
site, with a following plume that could cause considerable volcanism.
So, we have a likely attempted exit wound for the Chicxulub impact at
Zealandia. What about the other really large impact objects? In the past 252
million years, there have been four really large impacts.
WHERE |
WHEN |
EXTINCTION |
EXIT WOUND UPLIFT
|
Eastern
Antarctica |
252 MYA |
Permian Extinction
|
?? |
S. Indian
Ocean |
201 MYA |
Triassic Extinction -
CAMP |
Caribean Plate
Creation |
Mid-Pacific
Ocean |
132 MYA |
Valanginian Weissert
Event |
Ontong Java
Plateau |
Chicxulub,
Mexico |
66 MYA |
End-Cretaceous
Extinction |
Zealandia |
THE VALANGINIAN WEISSERT
EVENT
The really large impact
object that caused the Valanginian Weissert Oceanic Anoxic Event and left its
mark on the Mid-Pacific Ocean floor 132 MYA and whose remnants later became the
Mariana Trench (and who's antipodal impact effects created the separate
continent of South America) has a likely correlative attempted exit wound
bulge.
Located just below the equator, the Ontong Java Plateau off New
Guinea is one of the largest volcanic events of the past 200 million years. The
eruptions began with the Selli event 125.0 to 124.6 MYA. this is just about the
right timing to allow approximately eight years for a mantle plume to melt its
way through the Earth's crust, if it began 132 MYA. The uplifting of the
plateau may or may not have been solely due to the volcanism
the impact
object's exit wound attempt may have been a significant part of the uplift.
Most of this vast plateau has now been subducted beneath the Australian
plate. In fact, this subduction illustrates the problem that we may be running
into with a Permian extinction object that impacted 252 MYA. If there is a an
attempted exit wound uplift for this impact, I can't find it. It may be that
during the 252 million year interval, the uplift has been completely
subducted.
TRIASSIC EXTINCTION -
CAMP
The Triassic extinction
and the Central Atlantic Magmatic Provinces (CAMP) occurred around 201 MYA.
The impact object associated with this event likely impacted in the
Southern Indian Ocean. The likely location for an attempted exit wound for this
impact object object is the Caribbean Plate. According to Evolution of Middle
America and the in situ Caribbean Plate model by Keith H. James, the "plate
history began along with the Late Triassic formation of the Central Magmatic
Province
" The paper continues with an explanation of how this oceanic
plateau contains continental fragments of plate interior as well as extensive
volcanism.
The timing is right. The location would make sense. The
creation of a separate plateau with no other definitive explanation makes
sense.
EXIT WOUND
SUMMARY
Except for the oldest
impact of 252 MYA, we have reasonable attempted exit wound locations for the
three other really big impacts of the past 250 million years. The timing for
the creation of these attempted exit wounds fits in with the date of the
impacts.
It appears that we have found specific confirmation for the
concept that very large cosmic impacts have punctured the Earth's crust and
have created attempted exit wounds. This evidence is in addition to extinction
level volcanism at the antipode of the impact and tectonic plate
creation.
CONCLUSION
Ben's Antipodal impact Theory establishes reasons to believe that
contemporaneous mantle plumes can result from very large impacts by cosmic
objects as they collide with the Earth. The mantle plumes are created by the
extreme pressure brought to bear at the liquid olivine layer next to the
Earth's core, combined with the lack of frictional resistance in the Earth's
mantle as the shear forces pass beyond the Frictional Release Threshold. This
chapter explains a mechanism by which the four very large impacts of the past
100 million years could have caused mantle plumes at or near the antipode, as
well as illustrating a threshold principle by which smaller impacts may not be
able to produce mantle plumes.
The Next Chapter, entitled "The
Statistical Justification for Contemporaneous Impacts and Mantle Plumes"
establishes the statistical and geological evidence that mantle plumes
contemporaneous with very large impacts have occurred in all four of the
largest impacts of the last 100 million years.
IMPACT
#A IMPACT #B IMPACT #C IMPACT #D IMPACT
#E IMPACT #F IMPACT #G
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