Week 3 of my Scottish Borders fieldwork was the team fieldwork week. We all got together to do some extensive sampling, look for fossils, examine a few different sites and discuss the science together.
Who was there from team TWeed? And what were they doing?
University of Leicester – me and Sarah Davies: looking for ostracods (just me on that one!), sedimentary logging, describing sedimentary structures in the field and collecting samples for analysis back in the lab.
ambridge team (Cambridge Museum of Zoology and the Sedgwick Museum, Cambridge) – Tim Smithson (vertebrate palaeontologist), Rob Clack (amateur vertebrate palaeontologist), Sarah Finney (vertebrate curator), Ket Smithson (new PhD student on fossil fish). Project supporter Marcello Ruta from the University of Bristol (tetrapod specialist) also visited. The team were examining different sites and fossil collecting.
British Geological Survey – Tim Kearsey: sedimentary logging, sampling, palaeosols expert, integration of BGS maps and records, digital recording using the GPS.
University of Southampton – John Marshall, palynologist and expert in Devonian/Carboniferous climate change: sampling with the Leicester and BGS team, to examine the microfossil (palynomorph and charcoal) content of the samples.
National Museum of Scotland – Palaeozoic fossil experts and curators Andrew Ross, Stig Walsh, Sarah Stewart and Simon Howard: fossil collecting and identification.
It was a very busy week: the Leicester, BGS and Southampton team logged another 50 metres of section, and took around 250 rock samples. To produce a high resolution data set (i.e. lots of data points throughout the Ballagan Formation) we were taking samples approximately every metre throughout the section. For each one we recorded the sample position on the sedimentary log, the GPS co-ordinates of the sample and a photograph of where the sample was taken.
Left: Tim Kearsey (BGS) and Sarah Finney (Sedgwick Museum). Tim is holding a precise GPS locator, so we can pin-point where the samples come from and digitally record that information. Right: Tim Kearsey and John Marshall looking very enthusiastic despite the rain.
What will we use the samples for? We will study the following:
- Sedimentology of the rocks, the types of sediment they are composed of. This can tell us about how the sediment formed, for example comparing the composition of different sandstone bodies can tell us if they all came from the same source.
- Microfossil content of the sediments, revealed by processing and sieving the samples (see blog 3). We will look for vertebrate, invertebrate and plant microfossils. The type and number of microfossils can tell us what the environment was like.
- Geochemistry of the rocks, which can tell us about the source of organic matter in the rocks and the environment in which the rocks formed.
The vertebrate palaeontologists in the team had a busy week, collecting bulk samples from different parts of the section exposed on the foreshore, to be worked on back in Cambridge over the next few months. Already scales of a group of fishes not previously found in the Early Carboniferous of the Scottish Borders have been identified. Three members of the team, Ket, Sarah and Marcello, had not been to Burnmouth before and Tim showed them the different beds where fossils had been collected in the past. Tim also took Ket, who will be studying for a PhD on some of the fishes being collected in the Borders, to the inland sites. These are all in the banks and beds of the local rivers. Unfortunately, because of all the recent rain, these rivers were in flood and collecting was impossible. They'll have to be patient and hope for more clement weather in the spring.
Mid-afternoon on ‘dreadful Tuesday’, we’re having a cup of tea and discussions in the cottage, while drying off our socks!
In the next blog will be about cutting and polishing rock samples to reveal their secrets.
Until next time