241 replies to this topic

[Shamalama]

pleecan, on 19 April 2010 - 08:38 PM, said:

Dave: Here is the photo of that strange looking cephalopod... think you are right closer to pelecyod.
Peter

2010_0419arkona30002.JPG

Yep, that indeed looks like a Leiopteria to me. The odd thing is it looks like just a skin of the shell, no real impression. Odd.

Thanks for the tips on where to look!

[pleecan]

Arkona Hash Plates:
Plate A=3"x2"
 IMG00484.jpg   314.59K   17 downloads

Plate B= 1"x 1"
 IMG00488.jpg   184.12K   15 downloads

Plate C= 2"x1"
 IMG00491.jpg   340.25K   16 downloads

Plate D= 2"x1.5"
 IMG00505.jpg   263.79K   24 downloads

Plate D=Flipside
 IMG00504.jpg   232.54K   25 downloads

Plate E=3"x2"
 IMG00507.jpg   358.48K   17 downloads

Plate F=2"x1"
 IMG00513.jpg   150.5K   18 downloads

Edited by pleecan, 22 April 2010 - 08:10 AM.

[michigantim]

I like plate D!

Waiting on a lens mount flash -- the Greenops I found are tiny, and I'm getting a shadows...

more soon...
Tim

[Shamalama]

Nice plates, is that Widder formation?

[pleecan]

michigantim, on 22 April 2010 - 08:30 AM, said:

I like plate D!

Waiting on a lens mount flash -- the Greenops I found are tiny, and I'm getting a shadows...

more soon...
Tim

Hi Tim:
Shadows are sometimes a good thing as it will bring out relief on the fossil giving it a 3D effect.
Just use an ordinary table lamp with a 23 watts CFL spiral wound bulb (white light)( equivalent to 100watt bulb output) ( Cool light= 6000 Kelvin) as oppose to soft light which give an orange/yellow light at 5000Kelvin and your shadows will disappear... I rarely use the flash on the camera when taking macro... all external lamps for lighting.

Peter

[pleecan]

Shamalama, on 22 April 2010 - 10:01 AM, said:

Nice plates, is that Widder formation?

Yes... Widder Formation that sits ontop of the Arkona Shale that had been eroded and fell into the Arkona Shale layer.

[crinus]

pleecan, on 22 April 2010 - 03:08 PM, said:

Yes... Widder Formation that sits ontop of the Arkona Shale that had been eroded and fell into the Arkona Shale layer.

Sorry pleecan, but the crinoid hash layer comes from the Arkona Formation. These pockets of hash are the bases for the crinoid pockets. Here are a couple of photos showing the shale with the hash layer and crinoids on top.

crinus


 DSC09904.JPG   84.5K   30 downloads  DSC09905.JPG   92.22K   26 downloads

[Shamalama]

Hmmm... so find the crinoid hash and you just may find whole crinoids on top?

[pleecan]

crinus, on 22 April 2010 - 03:33 PM, said:

Sorry pleecan, but the crinoid hash layer comes from the Arkona Formation. These pockets of hash are the bases for the crinoid pockets. Here are a couple of photos showing the shale with the hash layer and crinoids on top.

crinus


DSC09904.JPG DSC09905.JPG

Thank you Crinus for the clarification.... I found these on surface in the south clay pit... so these must be refered to what some people called crinod lens formation in the Arkona shale formation are the tentaculite plates from the Widder Formation then or are they from the Arkona Formation also.
PL

[pleecan]

More Arkona Close up Hash Plates:
 IMG00499.jpg   418.65K   7 downloads

 IMG00501.jpg   311.03K   6 downloads

 IMG00507.jpg   358.48K   4 downloads

 IMG00516.jpg   176.61K   13 downloads

Attached Files

•  IMG00516.jpg   176.61K   5 downloads
•  IMG00518.jpg   302.8K   6 downloads
•  IMG00517.jpg   152.14K   15 downloads

[crinus]

pleecan, on 22 April 2010 - 09:38 PM, said:

Thank you Crinus for the clarification.... I found these on surface in the south clay pit... so these must be refered to what some people called crinod lens formation in the Arkona shale formation are the tentaculite plates from the Widder Formation then or are they from the Arkona Formation also.
PL

The tentaculid plates are also from the Arkona Formation.
Crinus

[pleecan]

crinus, on 23 April 2010 - 12:02 PM, said:

The tentaculid plates are also from the Arkona Formation.
Crinus

Thank you Crinus for the information!
PL

[micropterus101]

wow thats just amazing what you are finding there! Would a metal detector help find the pyritized stuff?

[pleecan]

micropterus101, on 23 April 2010 - 03:53 PM, said:

wow thats just amazing what you are finding there! Would a metal detector help find the pyritized stuff?

A pulse inductive metal detector may detect iron rich deposits that may increase the chances of finding pyritized fossils.... I have tested a high end PI metal detector and placed a dozen pyritized goniatites in a ziploc bag... net results... no detection.
I have already tested a bunch of metal detectors with this concept and came up zero... see discussion thread.

Simplest way to detect pyrite is to wait till a rain fall then go hunt in the sun light and the reflection in the sun light will help one zero in on the pyritized fossil... I am able to pick up pyritized microfossil as small as 2mm with this technique.
PL

Edited by pleecan, 23 April 2010 - 08:32 PM.

[crinus]

Shamalama, on 22 April 2010 - 06:29 PM, said:

Hmmm... so find the crinoid hash and you just may find whole crinoids on top?

This is correct. However, since they are not working the pits you find no new hash layers. In the old days (don't you hate hearing that) you would come to the pit on the weekend after they scrapped off several inches of clay and look for hash layers. When you found a hash layer you started digging and 9 time out of 10 you would hit a crinoid pocket. Sometimes the pockets were about 5X5 feet and lots of crinoids. But that was in the old days.
These days one needs a dozer to remove the clay layer.
crinus

Edited by crinus, 23 April 2010 - 11:51 PM.

[michigantim]

Yes, Crinus, I (we) do hate hearing that!

So, I was able to squeeze about 5 hrs. in last Sunday, 4/18/10. Originally, the plan was for an all day Fri. hunt, but that got blown out of the water by work schedules. Though I could have hunted from sunrise to sunset, you can find some good stuff in half a day.

I started out early poking around in the North Pit, spending about an hour looking for the fabled Arkona Shale lenses. Just as I was about to leave, I scraped across some hard matrix -- a lens! Well, it looks to me to be all brachiopod hash, but it was fun digging it out. No pictures yet. Still have to clean it up.

Then it was off to the South Bluff. The river was still up a bit, but judging from the high water mark, not as much as it had been. I had brought my neoprene chest waders, and a full backpacking pack for my gear. I started to cross a shallow spot, but the boulders were too slippery. I moved up stream, past a big pool and a fast chute above it. About 10 yards above the chute, the water was slow, looked about chest deep, and fairly rock free. I slipped in the water. About mid-stream, it started getting really deep. I hadn't considered that my pack would add buoyancy. I floated up just enough for the current to push me over and started me downstream. "No way am I going down that chute!" So I did the only thing I could, sat down, turned around, and dug my boots into the gravel. That worked, and the water down my waders gave me some stability. I made it to the south shore, dumped my waders, and started poking around.

There was a lot of fresh-fallen shale and a bunch of blocks of Widder. All of it was fairly dirty, so I'm thinking it came down with the thaw. A few good hard rains should turn all that into good hunting. The only thing worth noting from surface collecting is a nice big segment of cephalopod.

One of the pieces of Widder that had fallen was huge, at least 500 lbs. I spent most of my time working on that. Lots and lots of Greenops pieces. Over a 3 hour span, I did find 3 whole Greenops. They are all small, a little bigger than a nickel (forgot to measure them). One is really nice, one has a crack running down the right side thorax, and one is sharing it's exoskeleton -- half on the positive, half on the negative.

I also found several Tornoceraus in matrix. Best one shown.

After a very long walk to back to parking, I got to meet Pleecan (Peter), a super nice guy. Due to my boulder splitting obsession, we didn't get to do much more than chat, but I'm looking forward to some future hunts together.

At the border, the US customs dude gave me all the usual questions. "What have you been doing?" "Fossil hunting" "Where?" "H.H." Then he looked right at me and asked, "Do you have any firearms?" "No sir." "Well, what did you use?" "Hammers, chisels." "Hammers???" "Yeah, you know, rock hunting equipment." The guy did a big mental double-take and said "Oh, fossil hunting! I thought you said possum hunting!" (I could see this guy's mental picture of me whacking a possum on the head) I said, "Hey, there's no season on those guys, but I just use my car." He said, "Have a nice day."

Yes, sir!

Attached Files

•  April 2010 070.JPG   420.27K   16 downloads
•  April 2010 062.JPG   232.78K   33 downloads
•  April 2010 068.JPG   90.95K   26 downloads
•  April 2010 067.JPG   538.26K   29 downloads

[Auspex]

Great report; got my heart rate up with the river crossing escapade! Sweet finds; congrats

[michigantim]

Thanks, Auspex!

Nothing like a little adventure, some nice fossils, and a new friend to make for a memorable day.

Tim

[Northern Sharks]

Tim: I only wish I was there to see that. I can relate to how slippery those rocks are, but I managed to stay vertical. That is an impressive cephalopod piece

[pleecan]

Those are great finds Tim! Great shots with the new camera.... as an aside

(I chicken out and did not chance crossing the river as it was high water and running fast that would have flooded my rubber boots.... being a non swimmer... did not fancy the idea of slipping on the algae coated rocks and possibly drowning and be carried down stream .... the good stuff was across the river where Tim was hunting.... Pete's survival instincts.... if situation looks threatening... run away to live another day.)

PL