New impact craters found in Africa

[liberto]

I do not know if this is the correct place to put this note, but I would like to inform that there is a Spanish home-scientist whom has <b>discovered two impact craters</b> in Africa by using just the Google Earth tools.<br /><br />If you want to read about it, you can see http://www.astroseti.org/impacts.php it is in English and you can recommend it to your Spanish friends as that web has literally hundreds of articles from NASA, NAI, Planetary Society, SETI Institute, ESA, Kepler and news (several published in <i>Space.com</i>), all translated into Spanish. The translations are made by the non-profit group of translators whom belong to the Astroseti team and whom have the authorization from the mentioned sources to do so.<br /><br />In case somebody would like to send a direct answer I can be contacted at e-mail brunc@servicam.com<br />

 

[mlorrey]

Very interesting site. I followed the suggested links, and started browsing Google Earth myself. I shortly found what I believe to be an unreported impact crater at Jabal Tehilla, at:<br /><br />E 36.11753111902613<br /><br />N 17.76340292056212<br /><br />It shows about 3/4 complete rim and central structures, and, best of all, is at the same latitude as the previously confirmed Gweni-Fada Crater 15 degrees to the west, in Chad (implying multiple impacts from the same original body while the Earth rotated underneath).

 

[mlorrey]

Here's an image.

 

[silylene old]

I think I am going to do some crater hunting too!<br /><br />btw, here is an interesting circular crater-like depression I found while hiking in Maine last summer. I don't think this "crater" was carved by a glacier, as it is on a mountainside (instead of a valley), and I don't think it was volcanic (though this is possible). The slight tilt is due to the way I held my camera. <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[mlorrey]

Be happy to review it when it becomes available. Maine, NH, VT and NY are abysmal for finding impact craters, as the entire region was bulldozed into the ocean during the last ice age. Most depressions you find are typically the result of large chunks of ice buried under glacial till by the retreating glaciers. When the ice melts, it leaves a nice pothole in the ground. Such are found all over and can be many sizes.

 

[yevaud]

Same here, south of you. Not much left that wasn't scoured by glacial action. <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[mlorrey]

I have found a second location that also appears to be an impact site, to the east of the one I found. If it pans out, this is three impacts along the same line of latitude.

 

[mlorrey]

Ah, I see the clearing in the center, but do you have any close up images of a rim where your dotted line is?

 

[CalliArcale]

I think this thread would actually fit better in Space Science & Astronomy, so I'm going to move it there. It's a good place for discussion of terrestrial impact craters. <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>

 

[silylene old]

This location had relatively little glacial till in general as far as I could tell - mostly all slick rock, highly polished by several ice ages worth of glaciers. It could be a pothole left by till over a chunk of melting ice, but I thought maybe not. I don't know, and I am not a geologist, but I considered the possibility. I googled the location after the trip and found nothing. (I do know what the obvious glacial potholes look like - in fact I hiked a very nice pothole state park in MO several times - this one looked different. There is a depressed area about 2x-3x the size of the little pond in the middle).<br /><br />It's on a mountainside in Acadia Nat'l Park, about 15% up the mountain. As I said, maybe it could be a volcanic crater vent remnant, since the mountains in Acadia did originally have a volcanic origin long long ago.<br /><br />Acadia Park does have some pothole ponds, but not in that location.<br /><br />No, I didn't hike all the way to it, though I wanted to. I was hiking with my wife and she was tired and unwilling to bushwhack to it. I'll go next time. <br /><br />I know it has relatively little chance of being a meteor crater as that area has been picked over by scads of geologists...the "crater" just caught my eye and I had to photograph it to plan a hike there for my next trip. <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[mlorrey]

Ah, in Acadia, that explains things. That is a pothole, of a different sort, which may have ground some softer rock out that would have been volcanic, but Acadia's rock, when it formed originally, was deep underground. Its all igneous rock, essentially a solidified magma chamber. All the rock and soil that was once above it is now out in the Gulf of Maine.<br /><br />Depressions on hilltops and saddles like that are common, they create "vernal pools" if shallow, I've got one next to my house here in NH. If deeper they'll form peat bogs, or get dammed up by beavers.

 

[JonClarke]

You could try going over the ground with a metal detector. Absence of nickel iron fragments would not disprove that it is impact, but finding them would certainly support the possibility.<br /><br />Jon <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[silylene old]

Jon, good idea. I do have a metal detector.<br /><br />It could be just a pothole (probably is!). I have seen hundreds of pothole ponds and depressions. But it had just the right shallow perfectly round bowl shape to just maybe not be a pothole. <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[liberto]

I have been trying to find some of those craters, but in the great desert in Australia; where there must be some crater impacts as well. However have not found any so far! Maybe it's because the resolution at 100% ends at an altitude of more than 2 miles - at least with my Google edition. (the free discharge version)<br />

 

[mlorrey]

I got mine at a resolution of 20-40 mile altitudes. I'd suggest starting at 100 mile altitudes and just scan along. Anything small that looks circular, zoom in on and check out, snap a screen shot and save and mark, then pan back out and move on.<br /><br />I'm using the free dowload version of Google Earth.<br /><br />One of the guys who maintains one of the impact archives said he especially likes the shape of the eastern impact I found. We may have a hit...

 

[mlorrey]

Here's an image of the easterly site I reported:

 

[mlorrey]

Is that site in Acadia called Sargent Mountain Pond? There's an okay sat image of Acadia in Google Earth, with landmarks (I suggest clicking on "terrain" as well, it adds some 3d to the image that you notice as you scroll.)

 

[silylene old]

No, that's not it. The pond doesn't show on any map I have looked at - it is rather small actually (I did google everything possible right after the trip). It does not show on google-earth, which has far too low of resolution to show it.<br /><br />As I recall, if you look at a map, it is about half way between Sunset Point and Otter Creek, on the east side of that ridge trail, about 3/4 the way down. Here is the best online map of Acadia: http://wuarchive.wustl.edu/pub/aminet/pix/park/AcadiaMap.jpg (but I could be remembering the location very slightly off too. I know I could find it again.) <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[silylene old]

An interesting abstract about a possible large crater in the Gulf of Maine at about the k/t boundry: http://gsa.confex.com/gsa/2003NE/finalprogram/abstract_51410.htm <br /><br />and<br />http://starryskies.com/articles/2003/04/impact.html <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[mlorrey]

Here's the response I got back from one of the impact database people:<br /><br />"Date: Mon, 17 Apr 2006 12:57:02 +0100 (MET) <br />From: fclaudin@xtec.cat <br />Subject: Re: Possible impact crater. <br />To: "Mike Lorrey" <mlorrey@yahoo.com /> <br />CC: kord@ernstson.de <br /><br />Dear Mike,<br />I've work on the images your alleged impact structures with Nasa World Wind program....You know, it allow you made a 3D reconstruction of the zone.... Afetr the preliminary study, I can conclude:<br /><br />a. You are a good observer. The structures clearly disrupted the normal structural trend in the zone....and they are circular.<br /><br />b. The Jabal structure is about 8-9 Km of diameter. This implies, according to the current knowledge (impact knowledge..), that is a complex structure...This means that many rings or central uplift could be expected... The east of jabal structure have an internal ring of roughly 2,5 km and the external ring probably was of 9 km ....another complex structure too in the case of impact (remember that in the earth the transition zone or diameter between simple and complex structures is located on 4 Km....)<br /><br />c. I've made some addings in the photographs (interpretation of the observed images; obviously is my intrepretation and evidently is an interpretation based on the images not in the fieldwork (better))...In red colours fractures, in Pink colours probably rings (sometimes as in the eastjabal...green colour is employed too in order to remark the other circular zone...)...<br /><br />d. In the case of Jabal, you can observe a circular ring only disrupted in the SW zone..In this zone the circularity disapear..There are no clear uplift inner zone; in fact, according to the images, you can observe a tectonic control of this zone (red line...and green circle in Jabal3). No inner ring observed too... An external ring seems present (see Jabal 1 and 2 images). According