Brisk Day In The Platteville Formation

[Caleb]

Woke up at 6:30am and it was 34°f and dark. I gathered my gear and headed off to pick up my father for a day of collecting in the Platteville formation of Southeast Wisconsin. A few weeks ago we had our annual outing with a friend of ours from Western Minnesota and discovered one of our "super-secret" sites had been worked recently. It was cold and rainy that day, so we just did a "quick" 2hr stop and gave everything a fast once over. Today was going to be the careful slow crawl in search for trilobites.

The quarry spans 2 members of the Platteville Formation; the Mifflin and Grand Detour members. Until this year we have foolishly written off the Grand Detour as mostly barren, but early this spring we discovered that it has many of the same trilobites as well as numerous echinoderms that are not found in the Mifflin.

We arrived at the quarry shortly before 10:00 after having a nice breakfast in a nearby town. The sleet had just stopped according to the land owner and with the temp at 37°f we started the slow crawl over the rocks. While the nice complete trilobites eluded me, I did come away with some nice study specimens and some of the more unusual things. The prize for me was a Starfish, possibly Hudsonaster narrawayi or Stenaster sp.(pictures to come next week hopefully). The runner up was the Amphilichas material which is quite uncommon.

Amphilichas sp. hypostome, free-cheek, and cephalon

Gabriceraurus mifflinensis with hypostome in place

Ectenaspsis homalonotoides hypostome

Raymondites longispinus pygidium

Ceraurinella scofieldi cephalon

Soon to follow, the non trilobite stuff.

[Caleb]

small coiled cephalopod, another ceph, and a very well preserved piece of cephalopod shell.

Gastropods:

Maclurites bigsbyi, and a Clathospira, both out of the Grand Detour member

And last, a crinoid, I'm thinking it's a Cupulocrinus gracilis

[Auspex]

I am particularly struck by the detail of the cephalopod shell!

[Fossildude19]

Excellent report and finds, as always, Caleb!

Can't wait to see the starfish!

Thanks for posting your reports- I always enjoy them.

Regards,

[Caleb]

I am particularly struck by the detail of the cephalopod shell!

The detail of the shell material is beautiful. Once in a while we'll find a ceph with the shell still on, but it's not common.

Excellent report and finds, as always, Caleb!

Can't wait to see the starfish!

Thanks for posting your reports- I always enjoy them.

Regards,

Thanks! I can't wait to get back to the quarry and pick the starfish up. Unfortunately while we were picking up our small piles to leave we forgot one and didn't realize until an hour down the road. Oh well, we know where it's at and it gives us an excuse to get back out on the rocks next weekend!

[fossiladdict]

Cool, yeah ready to see the starfish!

[Caleb]

Ok, we made it back to the quarry to pick up what we left last weekend that included the starfish. We also spotted another pile of stuff we had forgotten to bring home. I still have a hard time believing we left that much material, but at least it gave us an excuse to get back on the rocks. Anyway, here's the pic of the starfish...

[Bev]

Thank you so much for the report and all the pictures! Great finds! Love to hear about your trips and see your posts.

[Caleb]

Thanks Bev!

[Bullsnake]

Great report. Love the starfish...well, I like all of them! Thanks!

[masonboro37]

So enjoyed your report of the trip and pic's. That gastropod's are wonderful and and just great finds! Thanks for sharing.

[Missourian]

Nice. Starfish are always special. I hope it's all there and intact.

[trilobiteruss]

Great trip report!

[Caleb]

Nice. Starfish are always special. I hope it's all there and intact.

I hope it's all there as well. I've only collected a couple complete and this one will be my largest. 4 of the 5 arms are visible so that's certainly a good sign.