Field trip to the Late Cretaceous chalk of northern France

[The Amateur Paleontologist]

Hello everyone,

 

Tomorrow I'll be going for a day-long field trip to the Turonian chalk of Northern France - but I won't be going to the usual Cap Blanc Nez. Rather, I'll be going to a small exposure of chalk in a forest (near Hesdin). Last time I went, I didn't find much (apart from a few bryozoan fragments and a piece of a cidarid spine) - though I hope that this time, I'll find more material.. I plan to also take a few chalk nodules for me to work on back at home, and potentially find more fossils. I hope that what I find will be able to serve as some sort of "comparative research material" for my MKFRP project. 

 

Bucket list:

-Echinoderm remains of any kind (except holothuroid or irregular echinoid)

-Shark tooth

-(I know it's a long shot, but hey) Coniasaur remains

 

I'll of course post a report on TFF after the field trip.

 

Best,

 

Christian

[Heteromorph]

[Tidgy's Dad]

[FossilSniper]

[Miocene_Mason]

[ynot]

Good luck!!

 

 

[The Amateur Paleontologist]

Came back yesterday evening from my field trip to Hesdin.. It was quite good, I spent the entire afternoon over there.

The outcrop, given that it was located in a forest, was blocked out by quite a lot of branches, thorny plants, and other bits of vegetation. Setting up the quarry thus took quite some time as I first had to clear all that vegetation. And there were mosquitoes - rather large ones, at that!   

Unfortunately, the chalk was not the best quality, as there were roots from trees and other plants that had pushed through. On the bright side, however, it did make my job slightly easier, all I had to do was pull out a piece of chalk with little effort.

After a few minutes of cracking open blocks of chalk, I saw a tiny, brown and visibly fragile pattern on one of the pieces of rock. I had found a fish bone! Based on what I could see, it was the vertebral centrum of some small teleost fish. Yay! vertebrate material is rare over there, so I think this find was rather neat. 

Shortly after that, I found a few bits and pieces of inoceramid bivalves - some of the most common fossils over there. And then came another possible fish bone, but it's rather difficult to ID it  because it's just a few small brown traces. Oh well. Future research will hopefully tell more.

Despite my original find of the teleost centrum, I was getting rather disappointed at the near-absence of fossil material from this chalk. This place was definitely not in the league of sites like Møns Klint, in Denmark. 

I clambered down the steep and leafy descent back to the main path, for a small break. As I drink some water, I look a bit to my left and see that there is another, larger chalk outcrop. I immediately pick up my tools and go to that spot. Luckily, there's less vegetation covering the exposure, so it takes less time to set up my things. Within minutes, I realise that this place has even less fossils to give up than the previous outcrop. And the mosquitoes still haven't left me alone…

Using a small chisel, I aim slight taps with my hammer to bring down a large block of chalk. I break that boulder into several smaller pieces. I notice on one of largest pieces an unexpected impression. It looked like something that had points arranged in lines… Thinking that there must be in that block the thing that made that imprint, I look at another piece and see a club-like spine of a Tylocidaris! My first one! What's more, it looked like it was still continuing into the chalk. I look a bit around, and spot on the same block another spine from a cidarid echinoid (probably Temnocidaris or something like that). After having exposed some of it, I make the trip back to the first outcrop to pack up my stuff and leave. While I'm packing the piece of chalk that contains a possible fish bone, I notice that there is also a piece of an echinoid ossicle. All in all, this was quite a productive field trip. 

 

P.S. I'll soon post pictures of the specimens, right now they're still in their kitchen paper "field jackets"

P.P.S Expect also a post detailing faunal similarities and differences between the "Hesdin Chalk" and Møns Klint