Graptolite from Mimico Creek?

[Monica]

Hello there!

 

Well, I tried to take Viola out for a little fossil hunt by Mimico Creek in Etobicoke, Ontario (Georgian Bay Formation, Upper Ordovician) this afternoon because when I checked the forecast this morning it looked like it was going to be ideal fossil-hunting weather - a mix of sun and cloud with temperatures in the mid-20s Celsius.  When we arrived, however, it began to rain - we toughed it out and came away with one piece before it began to pour and we called it a day.  I was disappointed since I was hoping to spend a few hours there, but the one piece we took home looks like it might have a graptolite on it, which is quite exciting since I have yet to find one in my local haunts.  Please check out the photo below and let me know what you think:

 

Thanks in advance for your help!

 

Monica

[Ludwigia]

I'm not so sure Monica. Looks like it could also be a mineral stain. Are there records of graptolites in the Georgian Bay Formation?

[Monica]

1 hour ago, Ludwigia said:

I'm not so sure Monica. Looks like it could also be a mineral stain. Are there records of graptolites in the Georgian Bay Formation?

 

Hey Roger!

 

I'm not sure what it is, to be honest - we hammered the rock off of a larger rock because there was a partial bivalve on it (and there ended up being a partial bivalve imprint on the other side of the rock, along with a brachiopod imprint, which makes Viola very happy!).  I only noticed this dark area after I washed the rock and it dried.  According to Bill Hessin's book (2009), the graptolite Diplograptus foliaceus "appears to be restricted to the Georgian Bay Formation where it is quite common" (page 262) although he names other genera that have been found in other formations in south-central Ontario, too.  I don't know for sure if it's a graptolite or not - if it is, then it'll be a first for me, but if it isn't, then Viola will still like the rock because of the "shells" it has 

 

Thanks for checking in! 

 

Monica