Eman,
Thank you for your most erudite contribution to this recent conversation. I always learn something when you do elect to write. I am fascinated, regardless of my limited knowledge, with earth history, and particularly factors that helped to create the NMFZ. I suppose it's because I've lived here most of my life and I'm so familiar with the land forms that I would like nothing better than to take a backhoe and go snooping. So please continue to share your knowledge of the area.
Thank you for your most erudite contribution to this recent conversation. I always learn something when you do elect to write. I am fascinated, regardless of my limited knowledge, with earth history, and particularly factors that helped to create the NMFZ. I suppose it's because I've lived here most of my life and I'm so familiar with the land forms that I would like nothing better than to take a backhoe and go snooping. So please continue to share your knowledge of the area.
I do know that the Jackson Volcano was active 66 mya and that there are 2 extinct volcanoes in Virginia: Mole Hill and Trimble Knob, which were active during the Eocene for about 2 million years. There are also structures dotted along a line in the Midwest that I think have now been declared to be impact sites and not extinct volcanoes. However, with better research, one never knows when that idea might change. I personally will explore one of these structures in Hardin County, Illinois, soon and see for myself if there are any further clues left behind.
Thanks again for your participation. You are a much valued member of this group.
Cheers,
Lin
On Fri, Oct 31, 2014 at 1:41 AM, MEM mstreman53@yahoo.com [geology2] <geology2@yahoogroups.com> wrote:
In no particular order: Research now accounts what was once thought to be extraordinary plate speeds because there was a long-lived assumption that the present plate moved all at once. The research now suggests that the paleo-India Plate peeled off successively during the Gondwanaland break-up such that the existing plate on which India is embedded did not break off Madagascar as late as 25 mybp. Antipodal et.al. "evidence" would have been rolled up into the Himalayas between ?-55 mybp in the convergent boundary by the northern portion(s) of the paleo-India Plate. There is a possible impact crater off the west coast if India called the Shiva crater and an suggested age of 66± mybp. It is elongated at 300 x 150 miles and may be the largest surviving distinct crater on earth. Owing to its proximity to the continent and centrality to the plate, it is in no danger of subduction. It is more likely that this crater is interconnected to the Deccan Traps than Chicxulub. The Cretaceous saw a lot of impacts on Earth, suggesting a major asteroid breakup in the Jurassic or earlier which repopulated the asteroid belt for a while.A dozen times you were "directed" to do the order of magnitude math on inertia, mass and energy transfer. Even with a Chicxulub diameter of 110 miles and excavation depth of 12 miles, it did not even come close to reaching the mantle. The Chesapeake impactor left crater 24 miles in diameter for the main crater and excavated down to 8 miles. This illustrates the rapid drop off of penetrating energy going from smaller to larger craters. I can keep up with where we are but at one time, I believe you suggested that India was spun off Africa by the Chicxulub impactor. As most of the energy rebounded upwards, there simply was not enough energy imparted to cause the India plate to "migrate". I understand that you haven't done the simulation to verify your theory as you don't have access to a computer powerful enough. I am disinclined to locate some math calculations which can be done on the home PC which do take plasticity, inertia and original impact energy but once again I suggest you look unless you fear the results would stop your theory dead. Incidentally, South America was much closer and was already moving at the time of excavation.As to the Deccan Trap "hotspot", when a magma source empties then it stops abruptly eg Siberian Traps Siberia, The Palisades NYC. Patterson NJ etc. Magma does not surface through pulverized rock--You really do not have your mind wrapped around plasticity and binding pressures in the lower crust and upper mantle, but that has been pointed out before. With rare exception Magma is formed in the lower crust snd rises through hydraulic fracturing and subsequent incorporation of country rock as the roof of the chamber melts. Some have suggested and (soundly) that the Reunion hotspot was passed over by part of the Indian plate and while doing so it caused extra melting of the lower crust giving rise to a magma source. I am not current on the chemistry differences of the Deccans and Reunion and not sure where to look in Africa. I think further reading on current research would confirm the direction and rotation of the southern India Plate. I do know this, you can't just look a plates where they are today and assume that one stood still and the other shot off in a particular direction or that it zigzagged. One has to do both dating and magnetic orientation analysis in basalts and correlate them to index magnetic pole swaps and determine relative plate movement. Speaking of-- 65 million years ago --the Atlantic Ocean was just opening. Africa and South America was not fully rifted apart. South America was both rotating counter clockwise and northward towards North America( Plate).Fortunately for human life but, unfortunately for science is that mantle plumes are rare and most of their in history have been subducted. They also are inconsistent in size. The remnant of the plume which left the Bermudas was believed to have first contacted the crust underneath the Central US but owing to the thickness of the crust never made it to the surface. There is an unexplained extinct volcano 2500 ft underneath Jackson MS and a several surface volcanoes in Virginia but I don't remember their ages.All that said, the antipodal eruption theory as you've outlined falls down in the physics of rock deformation and magnitudes of energy/vs inertia. I pointed you to the single known occurrence of an antipodal formed feature and at the scale of size where 1/3 of the asteroid was excavated the antipodal dome was 1/30th(?) the mass of a solid asteroid. I seriously doubt that it is possible to impart any antipodal feature on Earth--While it is called Terra Firma it really is robustly capable of transferring earth-displacing energy of the level to which you continue to obsess over.Going out limb here but, there is no level of potential impactor in the known solar system that can deliver enough energy to move a tectonic plate even a centimeter. Plate movement is only driven by mantle convection currents and a concept called buoyancy. You also should revisit the Occum's Razor principle. and while at it unless you really do learn some structural geology--not just terms selectively used, the obvious holes in your argument will never get fixed. e.g. continents are rooted in the plate on which locate they do not move independently.EmanPS:I learned on my trip to Alaska that there is a huge block of Hawaiian basalt that is beached onto an area near Juneau. Apparently it was buoyant enough to have been pushed along by currents in a time of higher sea level...Who'd a thunk it?
From: "Ben Fishler benfishler@yahoo.com [geology2]" <geology2@yahoogroups.com>
To: "geology2@yahoogroups.com" <geology2@yahoogroups.com>
Sent: Thursday, October 30, 2014 10:42 PM
Subject: Re: [Geology2] Fwd: Meteorite Impact May Have Triggered Largest Pulse Of Deccan Basalt Eruptions
I am not aware of "inarguable tracts in oceanic crust that clearly show the direction of India's movement." I would appreciate a reference to this phenomenon so that I can read about it.But, what I can do is to point out what is missing from the oceanic crust regarding India's movement (according to the explanation of the current theory). Where is the sequence of seamounts and volcanic islands that should have been in evidence on the sea floor as India pulled away from the plume that caused the Deccan traps?The eruption at the Deccan traps spewed out 27,000 cubic miles of volcanic material ... far greater than all other individual eruptions except for the eruption of the Permian-extinction-causing Siberian traps 250 MYA (which, by the way, was the only other plume eruption that did not exhibit domal uplift). The volcanic activity did not stop there. As India raced north (at the puzzling speed of three times the usual rate of tectonic movement ... but explained in chapter 2.2 of my book) the western side of the peninsula was pushed up and under girded with vast intrusions of volcanic material. This activity was so extreme that the entire peninsula of India slopes noticeably from west to east and all of its rivers run in this direction.The speed of the movement of India did not allow the hotspot to break through to the surface along the western edge of the peninsula. The hotspot was not located below any specific area long enough for this heating and doming process to fully take place. Nevertheless, the hotspot continued to pump out prodigious amounts of underlain volcanic material until it reached the end of the tip of the Indian peninsula.At this point, if you believe the current theory, the hotspot activity abruptly stopped. Really? Here we have the second biggest hotspot known to the science of geology ... it produces 27,000 cubic miles of volcanic material at the Deccan traps ... it produces prodigious volcanic intrusions along the entire western side of India ... and then it just stops.Does this sound like any hotspot that exists in reality?If you look at this scenario from the point of view of my theory, there is a pattern of hotspot continuation, involving the creation of the Indonesian Island chain (only the western side of Java and Sumatra), starting in the east from Timor and moving up to and through Lake Toba in northern Sumatra (with the Mount Sinabung area to the northwest as its likely current location). The Indonesian Island chain is the most volcanically active area on Earth ... just what you would expect from such a prodigious hotspot.The sequenced illustrations at the end of Chapter 2.2 in my book show this continuation clearly.
From: "Lin Kerns linkerns@gmail.com [geology2]" <geology2@yahoogroups.com>
To: Geology2 <geology2@yahoogroups.com>
Sent: Thursday, October 30, 2014 8:03 PM
Subject: Re: [Geology2] Fwd: Meteorite Impact May Have Triggered Largest Pulse Of Deccan Basalt Eruptions
I agree with Kim's common sense approach to the laws of physics, as well as to say, if India moved to the west, then what made those inarguable tracts in oceanic crust that clearly show the direction of India's movement? I'm not going to argue with a signpost, but what you are suggesting is doing just that.LinOn Thu, Oct 30, 2014 at 6:23 PM, Ben Fishler benfishler@yahoo.com [geology2] <geology2@yahoogroups.com> wrote:The big problem here is that the current theory says that, unlike Australia and Antarctica, India moved to the north. I say that it moved to the west, along with Australia and Antarctica, putting it at the antipode of the Chicxulub impact 65 MYA. As far as I can tell, the only reason that the current theory creates this anomalous movement for India is that this movement goes along with the idea that the Deccan Traps were formed when India moved over the Reunion hotspot on its way to its present location.However, if the Reunion hotspot were the source of the Deccan traps, then we would expect to see domal uplift of the area surrounding the Deccan traps. There is no domal uplift, as reported by Dr. Hetu Sheth, after extensively studying the situation.The only way that the Deccan traps could create a nearly circular footprint along with no domal uplift would be for the eruption to funnel up through the pulverized rock at the antipode of a very large impact ... the Chicxulub impact ... which created a mantle plume that was large enough to include the physical antipode within its range. The magma would follow the path of least resistance and flow through this circular antipodal weakness, thus eliminating the need for several million years of domal uplift.There are many points of evidence showing the movement of India as it moved from its position at the antipode of the Chicxulub impact 65 MYA to its present location, as detailed in my new book, www.solvingthemassextinctions.com.
From: "Lin Kerns linkerns@gmail.com [geology2]" <geology2@yahoogroups.com>
To: Geology2 <geology2@yahoogroups.com>
Sent: Thursday, October 30, 2014 10:02 AM
Subject: Re: [Geology2] Fwd: Meteorite Impact May Have Triggered Largest Pulse Of Deccan Basalt Eruptions
The big problem here is that India was not leven ocated at the antipode of the Yucatan Peninsula. It was nowhere near it. Look at the maps of the time period. That in itself refutes your theory.LinOn Thu, Oct 30, 2014 at 1:16 AM, Ben Fishler benfishler@yahoo.com [geology2] <geology2@yahoogroups.com> wrote:Just because the current theory doesn't understand that India was located at the antipode of the Chicxulub impact doesn't mean that it is right. The other three large impacts of the past one hundred million years showed contemporaneous mantle plume activity at the energy antipode (located close to the physical antipode). There is plenty of evidence indicating that the Chicxulub impact followed suit.
From: "Lin Kerns linkerns@gmail.com [geology2]" <geology2@yahoogroups.com>
To: Geology2 <geology2@yahoogroups.com>
Sent: Thursday, October 30, 2014 1:15 AM
Subject: Re: [Geology2] Fwd: Meteorite Impact May Have Triggered Largest Pulse Of Deccan Basalt Eruptions
But Ben... didn't you see what the blogger wrote?
Be careful here. The impact did not initiate Deccan volcanism. That was caused by India rifting away from Madagascar (88 mya) and Seychelles (66 mya). The rifting and an unusually hot mantle underneath resulted in copious amounts of melt being generated in the mantle which found its way to the surface via the great tensional cracks formed when continents separate.Your theory has already been refuted, seen by many peers, and accepted. To continue with linking the two events by applying causation to the bolide is folly.I'm sorry, but you're beating, not a dead horse, but a non-existent one.Lin
On Wed, Oct 29, 2014 at 10:05 PM, Ben Fishler benfishler@yahoo.com [geology2] <geology2@yahoogroups.com> wrote:No. They still have more work to do. But they are getting closer!
From: "Kim Noyes kimnoyes@gmail.com [geology2]" <geology2@yahoogroups.com>
To: Geology2 <geology2@yahoogroups.com>
Sent: Wednesday, October 29, 2014 11:26 AM
Subject: Re: [Geology2] Fwd: Meteorite Impact May Have Triggered Largest Pulse Of Deccan Basalt Eruptions
Ahhh, now there we go! That makes more sense! I don't believe much in coincidences and it always seemed odd these two things happening nearly at once in a geological context. However, folks kept saying they didn't match up perfectly in chronology which stretched credulity for me. However, advocates for a causative relationship lacked proof.... and the time correlation has been better constrained and a mechanism offered. Nicely done!
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Posted by: Lin Kerns <linkerns@gmail.com>
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