14 September 2023

Coring and geophysics

Ever since I have been involved in our annual estuarine field trip, we do both surface sampling and coring. And normally, we do the coring on the last field day. This year, for reasons of tide and other logistics, we had to do it differently, and after the introduction day we immediately went coring. Initially, the idea was that, as usual, I would have half the students in the morning while the other half would do geophysics, and then after lunch we would swap. But then the geophysicists decided that they could only work at low tide, so they needed all the students in the afternoon. So only the day before, we decided I should get all the students in the morning. 

Having everybody go coring in the morning provided a bit of a challenge! We had one student with a medical issue which meant they could only do a limited amount of walking. And that morning there was a race on. That meant only limited vehicle access to the estuary! When I was still expected to have two separate groups, I had organised that they would be with me in the afternoon, after the race would have finished. That would make it easier to drive to where I needed to be, or at least most of the way. But that wasn't going to happen.

In spite of the restrictions we made it work. It did mean it took us a long time to get to our coring site. But we all got there, and we got ourselves a core. And there was a conspicuous black horizon in it. What did that mean? We would have to sample it for foraminifera. And then sample all the modern environments we could think of that could represent that as well. And then compare the microfossils.

Crossing a tidal channel on the way to the core site

When we were done with the coring and sampling we had lunch. Then we went to where the geophysicists would do their thing. I had never seen them in action, as I am literally always coring while they do that. This year was different! And they even did something entirely different from what they normally do. They basically surveyed the beach and measured electrical resistivity in the sand, and that way spotted a freshwater body. There was groundwater seeping out on the beach! I had never realised that was happening there. But that's what geophysics is for, I guess; to detect things you can't see.

Dei talking geophysics 

Things did get a bit late. I was getting a bit nervous as I was getting tired, and I knew I still had to bike home. The day before I had hitched a ride with Martin to Menai Bridge, and then taken the people carrier, with which I had transported to students, home with me. But I had to leave that behind, because the day after someone else would need it. So my plan had been to just put my bike in the back of the vehicle and drop that off on the main campus, where I pick the students up. But as the vehicle couldn't stay there, I knew I would have to drive back from the field to Bangor, unload the students, load the bike back up, drive the vehicle back to Menai Bridge (the bridge probably being one lane only not helping), and then bike all the way home. It was going to get late!

My colleague Katrien clearly noticed, so she offered to just drive me home. It is not much of a detour for her. I could just leave my bike behind! And then I could either just pick that up again with my own car some day, or hitch another ride with either Martin or Susan, and then bike back after all. The bike would wait. It was very kind of her! 

When I got home I was properly knackered. But the good thing was that I didn’t have to do anything strenuously physical the next day. I wasn't needed in the field, so I was just going to take a day working from home. I could really use that! And I was also happy to spend some time with the cat, given that over the weekend I had been away so much…

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