[LeeE (OP)]

I spotted these two craters while browsing in GoogleEarth but I've been unable to find out anything about them.  They're located in Nei Mongol and the closest large settlement I can find seems to be Xilin Gol.  There are known volcanic features in this region but they seem to be quite someway from these structures.  Similarly, there is a known, but much smaller impact crater, Tabun-Khara-Obo, about 366 km to the west.

Google Maps (see below) shows a label "Huarggen Tala" beside the larger of the two structures but I get no hits from this in a Google search.  Note that if you look at them in GoogleMaps Terrain view, the smaller northern structure appears to have a clearly defined central peak, typical of impact craters, whereas the larger southern structure is much less clearly defined.

http://maps.google.co.uk/?ie=UTF8&ll=44.198944,114.248199&spn=0.43123,0.752563&t=h&z=11

Unfortunately, we can't upload .kmz attachments for GoogleEarth, but the co-ordinates are  44°13'47.64"N 114°14'8.52"E

Updated:  Looking a little further to the East, I just noticed these three structures too:

http://maps.google.co.uk/?ie=UTF8&t=h&ll=44.342512,114.903259&spn=0.215089,0.376282&z=12

[JimBob]

To be listed in the earth impact database, a site needs to have been examined in detail by a scientist and have been shown that it is an impact crater. In their criteria section, there first must be the evidence as you have seen and posted - macroscopic evidence - and then microscopic examination and the finding of impact-related structures in the rock.

I am sure that if those exterminations had taken place they would be published. Perhaps they have not been done. Who knows? Your not dealing with a place just outside of Newcastle here.

[LeeE (OP)]

Yeah, I know that only confirmed impact craters are listed in the EIDB, but I was a bit surprised that I couldn't find any references to them at all, not even speculation.

[JimBob]

I was as well. Perhaps they are volcanic collapse structures. To the east of each of these two locations are things that look to me like lava flows, although the eastern of the two is a degraded land-form as is the structure itself.

[Geezer]

Somewhat off track, but possibly interesting. I tripped over this while trying to come up with a photo of two old "craters" in Mongolia.

In the Scots dialect, a "crater" is an old and decrepit person (like myself). You might hear someone say "the pair auld crater" which translates to "the poor old (human) creature". I suspect "critter" in the US has a similar origin, but that generally applies to non-humans.

Anyway, this was the oldest crater I could find in Scotland.


http://www.cosmosmagazine.com/news/1916/massive-impact-crater-found-scotland

[LeeE (OP)]

Yeah, I know what you mean JB - it does look like there are some flows to the N & E of them, and possibly even an older and larger flow to the south, which then bends through 90deg to the east.  The close proximity too, suggests a volcanic, rather than impact origin to me (they just seem a bit too close together, but different enough in character, for contemporaneous impacts).  A couple of volcanic craters like that wouldn't be too hard to accept though, and what looks like a central impact crater peak in the northern crater could just be a dome.

Then there's also the stuff a little further east too, which suggests it's all volcanic, rather than being a cluster of impact sites.

Ah well - I'll just keep 'em filed under 'unidentified' for now.

Re the Ullapool impact - funnily enough, I only just read about that a few days ago.

[JimBob]

Oh, Lee - almost forgot!

There is another explanation. These may have been dug by a Scottish-American moderator of this site while he was playing in his sand pile when young. They look to be old enough.

[Geezer]

Oh, Lee - almost forgot!

There is another explanation. These may have been dug by a Scottish-American moderator of this site while he was playing in his sand pile when young. They look to be old enough.

Now look here laddie, your rotten little smokescreen won't work. You're just trying to cover up for the fact that you knew nothing about the Ullapool crater.

(He's probably going to crawl back into his cave and sulk now.)

[JimBob]

NO, I put up my theory of explanation.

I guess I hit too close to home for Geeze, Lee.

[geo driver]

been lookin at the maps, why do you think there is a lava flow to the n.e?

[LeeE (OP)]

Umm... JimBob referred to features to the E, and I referred to features to the N & E & S, but no one has mentioned anything to the NE.

Looking even further east, and slightly south (and it's clearer to see in terrain view) there are lots of smaller circular crater-like features, with what may be flows associated with many of them:

http://maps.google.co.uk/?ie=UTF8&t=p&ll=44.168415,115.289154&spn=0.431454,0.490952&z=11

Now if you zoom further out, you can see how these features are located relative to Xilin Gol, with the two large craters at/near the western limit of this view and Xilin Gol on the eastern side (you may need to resize your browser window, or close the GoogleMaps side tab to see the full width - click on the little '<<' button):

http://maps.google.co.uk/?ie=UTF8&t=p&ll=44.040219,115.125732&spn=1.729558,1.963806&z=9

Finally, shift the map over even further to the east, and south a bit, and you can see a volcano field to the NW of the large lake.

http://maps.google.co.uk/?ie=UTF8&t=p&ll=43.53262,116.413879&spn=1.744305,1.963806&z=9

Now, I was able to find mention of this relatively small volcano field, specifically mentioned as being NW of the lake (but not in relation to being SSE of Xilin Gol), but like I said, there seems to be no mention of the more impressive larger features N & W of Xilin Gol.

You have to wonder if all of these features are related, and that the volcano field extends over a much greater area than implied by the few references I found to the small field NW of the lake.  The distance from the NW shore of the lake, on a heading of 299 degrees, to the two large craters is about 214 km (133 miles).