Once Again: Another large modern crater found in North America

9 Responses

1. Hi Paul –

   As you know, without some kind of good geological date, it is impossible to associate any geobleme with the YD.

   There is nothing in the Native American oral corpus that I know concerning an impact at that location in Louisiana. That is not to say that it might not exist or might not have existed, its simply that I haven’t run across anything.

   I do wonder about the fatality range given by the impact simulator. It strikes me as being far too low.

2. Hi Paul –

   For the amateur google Earth folks, I should add a warning here that it they’re looking in that area collapsed salt domes can be circular features as well.

   To the feature at hand, any oil gathering fractures around this?

   How about tektites from this one?

   The fatality range from the impact simulator is far too low, as the “bediasite” fall pattern from the Barringer Crater impact shows.

3. Hello for all

   The availability of the simulator was a big step for the research, it is a great tool. But certainly in the future will undergo adjustments inevitable. (Earth Impact Effects Program Robert Marcus, H. Jay Melosh, and Gareth Collins)

   When I use it for the simulation of small craters produced by low speed (<15km/s)meteoroids, I found it convenient not to use the parameters for meteoroids rock or ice.

   If you use the simulator with (Projectile Density in kg/m3) parameter rocky or ice to the meteoroid, they will explode and will not form craters.

   Based on other studies on the size of the meteoroid that formed other craters, I use a trick parameter, I use the iron meteoroids parameter.

   The simulation seems more consistent with the scale of craters already studied, and consequently a closer relationship in the new (small) craters. Even for the Barringer Crater.

   regards
   pierson

4. So, did Dr. Heinrich do any bedrock drills to verify his hypothesis? How did he arrive at a date? What were the depositional environments of the overlying surface sediments?

   The article seems sort of sparse on certain details, especially coordinates for the center of the feature. Don’t people realize that a good number of characters like us use earth viewers like Google Earth?

5. I found the coordinates by 2010.09.06:

   [ 30.763027 -90.72808
   Brushy Creek .05 low .069 1.5 to W 2 km wide ]

   “Nebraska Bays” far too old to be YDB — YDB debate — Little Creek “Brushy
   Creek feature” structure, Louisiana — blog by highly expert geologist Paul
   V Heinrich: Rich Murray 2010.09.06
   http://rmforall.blogspot.com/2010_09_01_archive.htm
   Monday, September 6, 2010
   [ at end of each long page, click on Older Posts ]
   http://groups.yahoo.com/group/astrodeep/message/67
   [you may have to Copy and Paste URLs into your browser]

6. IS THERE A GOOD FORMULA FOR THE KILL RADIUS OF A METEORITE (COMET, ASTEROID) IMPACT?

   I keep being amazed about the “mountain fell into the sea” story from Revelations, evidently based on observation of a meteorite impact. The person observing the impact survived, so was outside the kill radius.

   I am thinking of a kill-radius formula in analogy to these rules-of-thumb (not sure how accurate these are and if they can be justified by energetic considerations):
   Crater Diameter = 20 x meteorite diameter.
   Crater Cavity, Initial depth = 1/10 x crater diameter

   Thus, a 1 km bolide would create a 20 km diameter crater, initially excavate to a depth of 2 km.

   This should depend on whether we have an iron meteorite or a chondrite, and on whether it’s a long period comet or an asteroid. So, these formulas cannot be very accurate?? Examples (from Wikipedia):

   Barringer Crater: Iron Nickel, diameter 1.2 km, meteorite estimated at 50 m, so rule of thumb would give only 1.0 km, but that’s still fairly close.

   Ries Crater: Comet suspected [Gene Shoemaker], diameter 22 × 24 km, meteorite estimated at 1.5 km, so rule of thumb would give 30 km crater.

   But the velocities are not well known, for Ries crater a huge range of 15 km/sec up to 50 km/sec is given (German Wikipedia).

   SO MY QUESTION, FOR THE (REAL) EXPERTS: IS THERE A SIMILAR RULE-OF-THUMB FOR THE KILL-RADIUS, GIVEN THAT THE ABOVE RULES-OF-THUMB ARE NOT TOO FAR OFF, DESPITE UNCERTAINTIES?

   For the Ries Crater, the entire Central European region is mentioned as the extinction (kill-) area. So the kill radius would have to be several hundred km, or about 20 x crater diamter???

   This would apply to land impacts, not oceanic.

7. Dear Hermann

   Try using the simulator Earth Impact Effects Program, also it has its uncertainties, but it is quite interesting(Robert Marcus, H. Jay Melosh, and Gareth Collins.)

   http://impact.ese.ic.ac.uk/ImpactEffects/

   regards
   pierson

8. Hermann, you wrote: “I keep being amazed about the “mountain fell into the sea” story from Revelations, evidently based on observation of a meteorite impact. The person observing the impact survived, so was outside the kill radius.”

   The observer was the Apostle John, and he was “observing” a supernatural vision. Not sure that Revelations will be much help here.

9. Dear Pierson, great tool — except, nothing seemed to happen!! I tried 100.00 km from target, etc, standard data, a 60.00 degree angle. Is this out of operation [browser was Google Chrome]. WHAT DID I DO WRONG??

   Terry, sorry but you are definitely wrong, in the following sense: Although the author, St John (or as many believe, a later Elder called John), did have a supernatural vision into the future, he was basing his vision on things he knew from experience, so-called empirical knowledge. Most likely, there were reports, widely known in his region at his epoch, of Taurid impacts, which according to the Bailey-Napier group were frequent at his time.