Mississauga mud yields some marine creatures.

[markjw]

Lots of ordinary things lately at Etobicoke Creek and Joshua Creek. Of course, when I began hunting in April 2019, I couldn't imagine finding such treasures, but there you have it. At the former location, we seem to have fun finding "How many decent-size orthocone nautiloids can fit on one rock," and the number appears to be 10 or 12 in some cases ! We also seem to be able to find snakes when we lift rocks, which can be disconcerting.

 

Recently I noticed some unpromising "wavy surface" rocks, but they had a layer underneath with branching bryozoan fragments. Turns out, there are lots of them, and some are the largest chunks I've ever seen. So today I was out in the rain, getting muddy. I had to leave lots of great rocks...they were reasonably heavy chunks. Tree roots along the creek had split up the shales, pushed some promising rocks through to the forest floor, and dumped lots of slabs onto the creekbank. When I get some of these rocks cleaned up, I hope to post some pictures. 

 

Meanwhile, here is a group of recent finds.

[Fossildude19]

Wow!  

That multiple orthocone cephalopod death plate is impressive. 

Nice finds, good report. 

Thanks for posting.  

[markjw]

11 minutes ago, Fossildude19 said:

Wow!  

That multiple orthocone cephalopod death plate is impressive. 

Nice finds, good report. 

Thanks for posting.  

Thanks! I love those things.

[Monica]

Your photography skills are amazing, Mark!  Great job, and great finds!  I like the coral that you found - not too common a find in Etobicoke Creek - congrats!

[Jeffrey P]

Congratulations. That nautiloid death plate is a killer. Also love the bivalve shells.

[Paul1719]

Ditto on the Cephalopods! Beautiful!

[crabfossilsteve]

Yeah, that cephalopod plate is very cool.  It would be especially cool if you could get it polished or sliced and polished.

[MeargleSchmeargl]

With those cephalopod plates, I guess you could say you made a killing. (Insert The Joker laughing)

 

Definitely nice stuff! Ordovician, right?

[Monica]

2 hours ago, MeargleSchmeargl said:

With those cephalopod plates, I guess you could say you made a killing. (Insert The Joker laughing)

 

Definitely nice stuff! Ordovician, right?

 

I think I can answer for Mark - it's Upper Ordovician, Georgian Bay Formation.

[markjw]

5 hours ago, MeargleSchmeargl said:

With those cephalopod plates, I guess you could say you made a killing. (Insert The Joker laughing)

 

Definitely nice stuff! Ordovician, right?

Multiple homocide !!

[markjw]

3 hours ago, Monica said:

 

I think I can answer for Mark - it's Upper Ordovician, Georgian Bay Formation.

Monica, are you interested in branching bryozoans? I'm finding them at Joshua Creek in Oakville...right on the dividing line w/Queenston shales. The stratigraphy is fascinating...distinctive layers of intensely detailed trace fossils (the really common find here) , crumbly shales, rafinesquina imprints, then rafinesquina calcified bodies, then wavy sand, then big bryozoans. Sometimes stray ambonychia, and petrified black blobs, too. Only 2 orthocones ever.

 

You really have to work for 'em, but they're there if one is determined. 

 

The place is spooky and you get your feet wet. Say the word if you want detailed directions.

[JUAN EMMANUEL]

On 9/14/2019 at 10:45 AM, markjw said:

Monica, are you interested in branching bryozoans? I'm finding them at Joshua Creek in Oakville...right on the dividing line w/Queenston shales. The stratigraphy is fascinating...distinctive layers of intensely detailed trace fossils (the really common find here) , crumbly shales, rafinesquina imprints, then rafinesquina calcified bodies, then wavy sand, then big bryozoans. Sometimes stray ambonychia, and petrified black blobs, too. Only 2 orthocones ever.

 

You really have to work for 'em, but they're there if one is determined. 

 

The place is spooky and you get your feet wet. Say the word if you want detailed directions.

Hi Mark,

 

Is the divide between the Georgian Bay formation and the Queenston formation actually present there in Oakville? I have seen the Queenston formation when I would go by Bronte Creek on the QEW. Is the transition between the two formations sharp and abrupt or is it a bit more gradual?

[markjw]

Hi Juan:

The Georgian Bay formation ends in eastern Oakville, but sneaks westward for a bit at the lakeshore as far as Joshua Creek on Ford Drive beside the PetroCan. I've found flaky non-fossiliferous green shale with alternating thick grey rocks full of delicate shell impressions and zygospira. There is another associated layer full of trace fossils and another with BIG branching bryozoans. I am surprised that the formations "interleaf" like that.

 

Further north, Joshua Creek beside the Maple Grove mall has promising shale packed with trace fossils (really concentrated!) , but not much else.

The border is really mixed up. For example, you can go all the way to the path descending to 16 Mile Creek south of Oakville GO and there is one small outcrop packed with messy Bryozoans and brachiopods (I removed the obvious nice loose rocks, though!)

 

If you want to search in Oakville, I can offer a couple more pointers.

[markjw]

Morrison Creek is EMPTY, as is 16 mile creek north of Kerr as far as I can tell. I've found a few 'erratics'.

 

All the lakeshore beaches are full of interesting fossil rocks, but they are rounded and deformed. East of the Bronte harbour, the beach is particularly rich.

 

The 'stars' are brought in. Bridge fills and coastal "armour stone" have good contents. You have heard me rave about the "Gull River Formation" armour stone all along the Oakville lakeshore at Tannery Park and other parks. It is packed with the most amazing fossils I've ever seen, including many species of nautiloid, some bean-shaped, some as long as my arm, and immaculate, superb green Pterotheca expansa examples. Also gastropod beds galore. There are many hundreds of these giant cubed shaped rocks. The rocks are tan in colour. The fossils tend to be 'glaucanized' (?) to a green colour.  They do not lend themselves to collection, though. Better to photograph.

 

Happy hunting!