Tektites: 4 – Primary and Secondary Impact Craters

Primary and Secondary Impact Craters

The search for a fourth extraordinary “hypervelocity” impact crater [that could explain the Georgiaites tektites] led me back to Steven Dutch’s world map of impact events.

Impact Craters

Steven Dutch, Natural and Applied Sciences, University of Wisconsin – Green Bay

http://www.uwgb.edu/dutchs/planets/impact1.htm

Reading the associated text I noted that Steven Dutch had [like me] noticed that the impacts in Australia, North America and Europe are arranged into three distinct groupings.

If you didn’t know better, you’d suspect meteors were targeting Australia, North America and Europe.

It’s not that there are so many craters there, it’s that there are so many geologists there, plus countries affluent enough to do detailed geologic mapping.

A complete map would have the whole earth covered to the same density. To show you how hard it can be, the Chesapeake Bay impact structure, on the doorstep of Washington D.C., was not discovered until the 1990’s, because it is completely buried.

Steven Dutch, Natural and Applied Sciences, University of Wisconsin – Green Bay

http://www.uwgb.edu/dutchs/planets/impact1.htm

However, in the satellite age, I find it difficult to accept that the identification of impact craters is dependent upon the local population density of geologists [and their affluence].

Firstly, the majority of geologists travel the globe [usually at their employer’s expense] for their annual “field trips” during the summer vacation.

Secondly, given the sheer volume of satellite photography [and data of many flavours] that is currently available online it is easy to explore the Earth’s surface [in detail] without leaving home.

Therefore, it is far more rationale to assume that a crater grouping represents “secondary impacts” caused by the ejecta produced by a “primary impact” event.

The extraordinary “hypervelocity” impact craters are very large and vast amounts of material have simply disappeared. Therefore, it is safe to assume that some of the missing material has been launched high into the atmosphere [like an intercontinental ballistic missile] in large chunks so that they can fall back onto some [literally] far-flung corner of the Earth.

The mainstream consensus already applies this concept in the case of tektites.

Extending the consensus concept to encompass larger “blobs” of material is eminently sensible – especially as it provides a rationale explanation for the observed impact groupings.

Therefore, the remainder of this posting looks at performing a “reality check” to see if this hypothesis can locate the “primary impact” site that produced the Georgiaites tektites.

Interestingly, in North America, there is an easily identified convergence point in Hudson Bay.

A clear radial “splatter” pattern can be observed to the south of Hudson Bay whilst another linear track of craters leads towards Alaska.

Furthermore, the satellite imagery of Hudson Bay clearly identifies the impact point as an arc with a best fit radius of 230 kilometres [and a minimum diameter of 450 kilometres].

Hudson Bay - 2008-07-21

Almost 40 years ago, Beals (1968) proposed an impact origin for the great eastern arc of Hudson Bay, which extends for 650 kilometres through an angle of 155 degrees and has a coherent circular raised rim on its landward side. A rift extends at right angles outwards on the southeastern side and within the arc, the basin is filled with Proterozoic sediments. The best fit circle has a radius of 230 kilometres and the arc deviates from this circle by less than 10 km along its entire length. More recently, Goodings and Brookfield (1992) noted that closing the James Bay rift aligns the Sutton ridge to form an arc of 240 degrees, or two-thirds of a circle. The remainder is cut by the younger circular northern Hudson Bay cratonic basin. Apart from impact, no other plausible explanation has been proposed for this great ring fracture (and another ring fracture may exist outside this one).

Along the Hudson Bay arc, bodies of pseudotachylite, monomict and exotic breccias are associated with faults, and overlying sediments may show evidence of re-worked impact melts. If investigations are positive, Hudson Bay arc would form part of the largest identified multi-ringed impact on Earth, with a minimum diameter of 450 kilometres.

THE GREAT ARC OF EASTERN HUDSON BAY, CANADA:
PART OF THE LARGEST MULTIRINGED IMPACT BASIN ON EARTH?
Michael E. Brookfield, Land Resource Science, Guelph University, Canada
https://gsa.confex.com/gsa/2006AM/finalprogram/abstract_110873.htm

Unfortunately, the mainstream is not keen on the idea that Hudson Bay is an impact site.

Michael Brookfield informs us that there has been little mainstream interest shown in Hudson Bay because, quite remarkably, the mainstream has found “no definitive evidence” of an impact.

But, because no definitive evidence of impact was found, little has been published on the Hudson Bay arc since 1968. Recent studies of multi-ringed basins on other planets, and of other old multi-ringed basin on Earth (e.g. Vredefort), provide criteria for re-investigation and re- interpretation of published reports.

THE GREAT ARC OF EASTERN HUDSON BAY, CANADA:
PART OF THE LARGEST MULTIRINGED IMPACT BASIN ON EARTH?
Michael E. Brookfield, Land Resource Science, Guelph University, Canada
https://gsa.confex.com/gsa/2006AM/finalprogram/abstract_110873.htm

Steven Dutch boldly states that Hudson Bay “is not an impact site” whilst surreally commenting upon the adjacent “genuine impact sites” [which are strong evidence that Hudson Bay is actually a major “primary impact” site].

Not everything that makes an arc on a map or air photo is an impact crater.

Impact basins big enough to see easily on a map would result in huge volumes of impact melts and widespread distinctive deformation of the rocks.

Hudson Bay - impact sites

The arc on the east side of Hudson’s Bay is astonishingly circular,
but it is not an impact site.

However, two genuine impact sites are visible on this map (circled in red).

The pair of lakes just east of the arc are the Clearwater Lakes, a rare double impact site.

In the far southeast of the map area is the Manicouagan impact.

Non-Impact Sites
Steven Dutch, Natural and Applied Sciences, University of Wisconsin – Green Bay
http://www.uwgb.edu/dutchs/planets/impact-No.htm

However, for those that care to look, there is a really astonishingly amount of evidence that indicates Hudson Bay is a major hypervelocity “primary impact” site.

One of the first markers is that the mainstream has no credible explanation regarding the formation of Hudson Bay whilst repeating [what can only be described as] consensus waffle.

Despite being one of the most striking features of the North America continent, the reason for the existence of Hudson Bay is obscure.

It lies in the Precambrian core of North America, which comprises the Canadian Shield and contiguous platform regions (Laurentia – Hoffman, 1988).

HuBLE: The Hudson Bay Lithospheric Experiment
http://www1.gly.bris.ac.uk/~ibastow/HUDSON_BAY.html

Some geologists disagree about what created the semicircular feature, known as the Nastapoka Arc, of the bay.

The overwhelming consensus is that it is an arcuate boundary of tectonic origin between the Belcher Fold Belt and undeformed basement of the Superior Craton created during the Trans-Hudson orogen.

Some geologists have argued that Hudson’s Bay is possibly related to a Precambrian extraterrestrial impact and have compared it to Mare Crisium on the Moon.

However, no credible evidence for such an impact crater has been found by regional magnetic, Bouguer gravity, and geologic studies.

http://en.wikipedia.org/wiki/Hudson_bay#Geology

The second marker is the original bathymetry of Hudson Bay [which is now hidden under 250 metres of water and covered by sedimentary rocks] that reveals a crater that is over two kilometres deep in the middle of the Hudson Bay.

Hudson Bay - Bathymetry
Phanerozoic vertical motions of Hudson Bay
Detlef Hanne, Nicky White, Andrew Butler, Stephen Jones

http://bullard.esc.cam.ac.uk/~basin/pubs/hudson.pdf

Hudson Bay - Watershed

Maps showing the Hudson Bay watershed, major rivers and the position of the tree line.

Sources, pathways and sinks of particulate organic matter in Hudson Bay:
Evidence from lignin distributions
Zou Zou A. Kuzyk, Miguel A. Goñi, Gary A. Stern, Robie W. Macdonald
http://www.sciencedirect.com/science/article/pii/S0304420308001370

The third marker is the extraordinary rate of uplift [up to 3.5 metres per hundred years] experienced in Hudson Bay which is attributed to “post-glacial rebound”.

Hudson Bay - Uplift - meters per 100 years

The mean rates of postglacial uplift in the Hudson Bay.
Isolines show rate of uplift in meters per 100 year.

NORTH ATLANTIC TEMPERATURE ANOMALY
M.A. Vukcevic M.Sc. 2009
http://hal.archives-ouvertes.fr/docs/00/41/83/04/PDF/NATA.pdf

Rate of lithospheric uplift
Map of post-glacial rebound. Hudson Bay is in the region of the most rapid uplift.

http://en.wikipedia.org/wiki/Hudson_Bay

The anomalous rate of uplift is indicative of subterranean outgassing which is “trapped” below the surface layers of rock. Worryingly, the surface layers of rock also appear to be an efficient insulator because of the low rate of surface heat flow around Hudson Bay.

Hudson Bay - Surface heat flow
Variations of surface heat flow and lithospheric thermal structure
beneath the North American craton – J.C. Mareschal, C. Jaupart
http://www.geotop.ca/pdf/mareschalJC/Mareschal_and_Jaupart_EPSL_2004.pdf

The fourth marker is the “odd coincidence” that one of the two prongs of the Earth’s magnetic north pole has remained stationery over Hudson Bay during the 20th century.

Hudson Bay - Magnetics

It appears to be an odd coincidence that the maximum strength of one of two prongs of the magnetic North pole should be located so close to the centre of Geoid depression, and remained more or less fixed to same location during whole of 20th century, despite weakening intensity and the ‘apparent’ moving of the magnetic North pole a thousand or more miles.

Hudson Bay - Gravity anomaly

One of the largest negative gravity anomalies (the attractions of gravity being less than average) is centred over Hudson Bay.

NORTH ATLANTIC TEMPERATURE ANOMALY
M.A. Vukcevic M.Sc. 2009
http://hal.archives-ouvertes.fr/docs/00/41/83/04/PDF/NATA.pdf

Overall, the evidence suggests that a large “hypervelocity” [probably] iron-rich object has deeply embedded itself into the sub-surface rock to the west of Hudson Bay.

Additionally, the Hudson Bay “long range” ejecta was propelled forward towards Alaska [following the objects original trajectory] and was also funnelled towards the south via the “channel” at the south of Hudson Bay.

One can only wonder how many other features of the North American landscape were sculptured by the Hudson Bay impact.

Hudson Bay - Wider Area

Google Maps
https://maps.google.es/maps?hl=es&ll=53.46189,-77.783203&spn=14.336724,28.256836&t=m&z=5

Advertisements
Gallery | This entry was posted in Astrophysics, Catastrophism, Earth, Geology, Science, Solar System. Bookmark the permalink.

16 Responses to Tektites: 4 – Primary and Secondary Impact Craters

  1. Pingback: Main Sequence – The Outer Iron Core | MalagaBay

  2. Jim Coyle says:

    This is phenomenal and answers alot of my questions about geologic and geographic entities. You should try looking at The Drake passage between South America and Antartica. On google earth you will see a deffinite crater and impact trench, also possibly 3 smaller craters in a small cluster just to the north of it. The main crater has a classic double wall rim but the smaller hits appear to have filled in the west side of thue crater so no rebound cone or ridge is visible. The smaller craters do have central cone features. On one of your maps showing impacts around the globe I noticed one on about the same latitude but further west of what I’m proposing. Could be a 5th related hit kind of daisy chaining?

    • malagabay says:

      The Drake Passage is interesting… with a clear radial pattern.
      https://malagabay.files.wordpress.com/2013/12/the-drake-passage.jpg?w=440

      I am not sure what specifically you are looking at but there are lots of possibilities…
      https://malagabay.files.wordpress.com/2013/12/the-drake-passage-impact.jpg?w=440

  3. Jim Coyle says:

    you need to move to the east to see the double ring leading edge of the main crater. Also pull back a little bit more for a larger view. You will se how the 2 landmasses are pulled to the east with the impact and you’ll also see the 2, possibly 3 craters to the north and just behind the main one.

  4. Jim Coyle says:

    If you want to get right there just google south Georgia island or the Sandwich islands. Then again pull back aways to get the big picture. You’ll also see how thw sedimnets on the ocean floor were pushed ahead almost to Africa

    • malagabay says:

      Thank you! What an amazing structure.

      Seeing the two landmasses pulled to the east is extraordinary.

      Looks like it separated Antarctica from the Americas and opened up The Drake Passage that connects the Pacific to the Atlantic.

      The seafloor age indicates this happened very recently [in a geologic time frame] – say around 33 million years ago.

      There appear to be some amazing “resonances” in seafloor spreading, biodiversity and climate that may have been triggered by this impact.

      https://malagabay.files.wordpress.com/2013/12/the-south-atlantic.jpg?w=440

      https://malagabay.files.wordpress.com/2013/12/sandwich-islands.jpg?w=440

      https://malagabay.files.wordpress.com/2013/05/earth-seafloor-crust-age-1996.gif?w=440

      https://malagabay.files.wordpress.com/2013/05/earth_seafloor_crust_expansion.gif?w=440

      https://malagabay.files.wordpress.com/2013/05/phanerozoic_biodiversity.gif?w=440

      https://malagabay.files.wordpress.com/2013/12/phanerozoic-climate-change.gif?w=440

      https://malagabay.files.wordpress.com/2013/07/phanerozoic_sea_level.gif?w=440

  5. Jim Coyle says:

    As I was checking things out I looked for any climate changes in the 33 million yr range and found that was when Antartica started to glaciate. At that same time there was a down turn in atmospheric CO2. Coincidence?

  6. Pingback: The Drake Passage Impact Event | MalagaBay

  7. Jim Coyle says:

    As I was looking at Mr Dutchs globe of world impacts I noticed that there was a general Northeast to Southwest lay of the impact clusters. Maybe by following the same general line across the ocean floors more sub oceanic craters can be found?

  8. J Martin says:

    How does an impact bend the tail ends of South America and Antarctica, wouldn’t those bends indicate slow gentle hot deformation ? Perhaps not all the Earth has rotated as one whole part all the time.

    • malagabay says:

      Differential rotation is very possible with a fluid… like the Sun’s photosphere.
      Therefore, if the Earth was originally molten then differential rotation may have occurred… and there may still be some residual differential rotation occurring internally…

      Unfortunately, humans have only managed to scratch away at 0.1938 % of the Earth’s surface.
      Being charitable, this still leaves a massive 99.8 % knowledge “gap”.
      Geology: Mind the Gap
      https://malagabay.wordpress.com/2013/07/21/geology-mind-the-gap/

  9. Jim Coyle says:

    J MARTIN; The impactor I have hypothisized would have had to have been approx 75-100km in rough dia traveling approx 75,000 mph, angle of 35-45 degrees. The land bridge between South America and Antarctica was already stretching and when hit at the shallow angle it ripped the land mass open and moved it 1200 mi east shearing the side and dragging them along and leaving the frontal ridging as the Sandwich Islands. Please look at the Drake Passage impact threads and see if any of this sounds plausible to you. I appreciate yours or any input on the subject.

  10. Pingback: The Ups and Downs of Sea Level | MalagaBay

  11. Pingback: A Scandinavian Saga | MalagaBay

  12. Pingback: The Arabian Horizon – The Cherokee Compass | MalagaBay

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s