North Sea Core CIC

Kristina Andriuka from IOT Holland got in touch with us a little while ago with a request for some core samples for a conference booth. Instead of putting a few bits on a table, she created an amazing display. Really nice to see how a few pieces of core can spark such a creative design!

This week, Angela has been busy delivering core gifts around the Aberdeen area. It's for a project we worked on a lot, as it's been one of the biggest ones we've had recently. Now that most of them have left HQ, there's finally some room to move about again!

Every core delivery is different, and so was this one. The cores from well 73/14-1, a very remote well for UKCS standards, came in sturdy wooden boxes. But in this case the lids were properly nailed to the boxes, needing some tools to unlock what's in them.

We'll soon find out!

A recent core donation brought in some red beds that we don't often see in North Sea wells - the Devonian. The photos show parts of core number 2 from 37/12-1. Most of the interval consists of rather broken-up and dull bits of claystone, but as is often the case, there is the odd nice bit!

This new delivery came with a surprise. In a few slabs, we found a maze of plug holes drilled for paleomagnetic purposes!

The slabs will be great for teaching purposes, as the porosity and permeability values are presented in each core analysis plug hole.

Bits of core used for gifts

What's better than receiving a bit of core after delivering a talk?

That's what the organisers of the PGK monthly technical talks thought over the past few years.

We recently supplied them with a new batch of gifts that will hopefully land on desks and will be looked at for years to come!

One of the best formations in the North Sea when it comes to bioturbation is the Middle Jurassic Ness Fm. These slabs from the Cormorant field (211/21-13) in the UK Northern North Sea are a prime example of the burrows that can often be found in the lower delta plain environment of the Ness Fm.

This core from well 53/04a-9 is from the southern margin of the SPB, where the Zechstein evaporite succession has a limited thickness.

The wellsite geologists have attempted to interpret the classic Zechstein formation breakdown, but isn't it a challenge to recognise the Grauer Salzton in here?

YouTube video by GEO EXPRO Coring Step by Step - GEO EXPRO & Reservoir Group

We talk about core all the time, but what does it take to get it out of the ground? In a project with GEO EXPRO, we visited Reservoir Group in Aberdeen and talked to Coring Manager Europe Steve Rait, who walked us through the main elements of a coring assembly.

www.youtube.com/watch?v=ad_X...

An oil spill in a core 👇🏽

We have seen a fair bit of core, but this little oil spill was new for us. It sits in a thin and fine-grained bit of Buzzard sandstone from exploration well 20/04a-10.

The composite well log does not report shows in this interval above OBM, so what could it be?

"I have always found it difficult to describe rock properties based only on hand specimens. Working with the cores helped me a lot to understand the sedimentological relationships better and confirmed that my decision to study geology was the right one."

Student at Kiel University in Germany

This week, a couple of our sections were studied by Summer Mathias Wasadha from the University of Aberdeen. Thanks to Rene Jonk Ph.D. and Matthew Brettle for taking the initiative to make this happen, and to Dr Stuart Gordon Archer, John Howell, Adrian Hartley and Wiktor Luzinski for coming along.

Yesterday, we took delivery of some Buzzard sandstone core - from well 20/04a-10.

Striking things are the oil-stained sands versus non oil-stained sands, probably due to cementation, the well-developed Kimmeridge Clay, and the soft-sediment deformation visible in the sandstones.

As Greenbrae school in Aberdeen has been learning about the Pangea supercontinent, Mariel Reitsma paid a visit yesterday and showed some rocks that were deposited around that time.

Are you interested in a set of cores for your classroom, a visit from us, or a copy of the slides, please let us know.

In 2020, as the pandemic unfolded, Kirstie and Henk made North Sea Core official.

Now, this handshake is a symbol for Kirstie to move on and focus more on her career.

In the meantime, the rest of the team remains as dedicated as ever.

Kirstie, thank you so much for the work over the years!

Is this an oil-down-to or an oil-water contact? Lots to see in this beautiful Claymore Sand core that is currently on display at the Devex 2025 Conference in Aberdeen.

Also, this section was accidentally cored as the original target was deeper down.

We are now thankful this happened.. 😬

This week, we feature a core from the Western Canada foreland basin, showing a Lower Cretaceous section. Based on trace fossil content, Robert MacKeracher, from Mount Royal University, explained that this section was probably deposited in a lacustrine environment rather than shallow marine.

This core is from the Sirte Basin in Libya. It is an Eocene carbonate and evaporite succession belonging to the Hon Fm, showing an undulated but very sharp transition from anhydrite (gypsum) to carbonate deposition as sea level rose slightly. Isn't it a beauty!

You don't necessarily need to look at seismic to see nice faults - sometimes a bit of core is enough to observe spectacular examples of structural geology. For example, this bit of Upper Jurassic Claymore Sandstone from well 15/21b-50 near the Telford field in the Moray Firth.

Thanks to Serica Energy for joining our existing sponsors and further supporting our work!

Sponsors help us in our mission to save, store, and make core available for the next generation of geoscientists.

Every time our joiner Pat McCabe drops off a selection of newly made frames, it is exciting to see what he's got in his van. This time, it included two Brent frames, showing samples from the Broom, Rannoch, Etive, Ness and Tarbert formations in a row. So nice!

We asked ourselves at the end of 2023 - has the decline kicked in? Are people tired of seeing core? Actually, the contrary is true: we have shipped to many new places and have diversified in terms of sponsorships and collaborations. Ready for another good year!

A "normal" sandstone you'd say, but then you check the comp log and it turns out to be a Carboniferous one! This is well 15/19-6 in the Moray Firth, where Carboniferous rocks have hardly been drilled. Also note the fractures at the bottom of the core - maybe one could be drilling induced?

North Sea Core HQ is getting a upgrade with new racks to help organise all the relinquished core we take in!

Sometimes it’s hard to say goodbye to the the core products we create! If you fancy a framed piece of stunning Brent core in your home or office, we will reluctantly agree to let these beauties go… please get in touch at northseacore@gmail.com

Fantastic to see such a engaged crowd at the GESGB (Geoscience Energy Society of Great Britain) #BEOS2025 Core Workshop, with Henk Kombrink talking through the geological evolution of the North Sea using some of our prized teaching set

North Sea Core have not started taking in zebras, it’s just the Claymore Sandstone Unit of the Upper Jurassic Kimmeridge Clay Formation! These incredible alternating finely laminated mudstones, fine sandstones and coarser oil stained sandstones are from well 15/21b- 50 #NorthSeaCore #Geology

Sometimes the preservation of the core is almost as impressive as the core itself! These samples of Upper Jurassic Piper Sandstone Formation are from well 15/13b- 11. It shows the dramatic variability in grain size and cement, documenting deposition in a shallow shelf environment #NorthSeaCore

Last week we recieved these stunning slabs from well 15/27a-12B, kindly donated by CNOOC International. This core documents the transition from the Forties deep-marine sandstone below to the more distal fine grained sediments of the Sele Formation #NorthSeaCore #Geology

These incredible slabs are from 15/21b-50, just west of the Telford field in the Moray Firth. They show beautiful alternations of faulted fine muds and sands deposited in a deep-water setting. While not part of a discovery, you can clearly see oil staining in the sandstones #NorthSeaCore #Geology