SULPHUR

Any photos.I would like to see the impression they make and compare them with what I have found.

ps418

The photo of raindrop impressions in Beus and Morales, p. 194, is great. The book is great too, BTW. But I haven't seen any photos of these online (I haven't really looked though).

Patrick

ps418

There are also raindrop prints in the Proterozoic age Chuar Group (according to Ford, in Beus and Morales, p. 59), and the Triassic Moenkopi Formation (Chronic, Roadside Geology of New Mexico, 1990, p. 195).

Patrick

roxrkool

Here are some photos:

http://www.geocities.com/jghist/fossiltrace.htm - scroll down a bit

http://www.psiaz.com/Schur/azpaleo/T...tr/p001361.jpg

http://www.psiaz.com/Schur/azpaleo/T...tr/p001358.jpg



Cheers

SULPHUR

By the size and definition of the fossils they don't appear to be rain drops. The first photo appeared to be caused by mud bubbles.

Blankman

I looked on the web and couldn't find any decent pictures either. I can't believe there aren't any good pictures of fossilized raindrops! At the Geo Dept. where I went to school we had several really cool (and obvious) fossilized raindrops. Sorry.

Claudia

I have seen some in-situ, and I have had a look on french web sites (look for "gouttes de pluie").
Here are the results:
http://www.etab.ac-caen.fr/discip/ge...t/sac00049.jpg

http://www.ac-nice.fr/svt/sorties/argens/gouttes.htm
this one coming from this site:
http://www.ac-nice.fr/svt/sorties/argens/arret5.htm
which is not far from the place where these photos have been taken:
http://www.ac-montpellier.fr/pedagog...ou/figures.htm
I have personally seen the footprints of pre-mamalian reptiles which are on this last page, and it is where I have also seen fossils of raindrops

ps418

I've never seen or read anything about sedimentary structures produced by "mud bubbles." Further, most of the putative raindrop impressions Ive seen are indeed impressions or tiny craters, which would require something to fall onto the sediment surface from above and would rule out an origin from bubbles rising from below the sediment surface. Also, this would only be possible in very fine grained sediments (e.g. mud), because otherwise the sediment would be too permeable for bubbles to form.

Patrick

SULPHUR

The only way I can see them forming is in an arid area and then being covered by aeolian sediment.

ps418

That's certainly the case with the Coconino Sandstone specimens. However, I can think of some ways for them to be buried by waterborne sediments as well. For instance, they could form in freshly deposited sediments on distal tidal flats, then the distal tidal flat could dry out and harden, then the pitted area could be buried by sediment when the tide reaches the distal flats once again. Certainly many fairly delicate trace fossils are preserved this way, so its at least possible for raindrop impressions to be preserved this way as well. I dont know of any examples in tidal deposits off the top of my head though

Patrick