Extracting formation temperatures from stalagmites
BGS’s Andrew Smith explores the karstic depressions of northern Spain in the quest to create a palaeothermometer.
14/08/2024
As part of our NERC ‘Exploring the frontiers’ grant, Dr Peter Wynn of Lancaster University and I have been out undertaking fieldwork in the Matienzo valley in northern Spain. The Matienzo valley is a fantastic karstic depression; it’s over two million years old and contains hundreds of kilometres of natural cave systems. Beyond its fantastic history of use as a repository for scientific data, the region is also heavily used by recreational cavers and cave explorers.
Our current work is focused on a small cave system called Llanio, just outside the main Matienzo karst depression. The work aims to develop a novel method for extracting cave speleothem (stalagmite) formation temperatures.
Cave temperatures
Caves have stable annual temperatures, only fluctuating within one degree over the annual cycle. This stable temperature reflects the average external annual temperature very accurately. For this reason, the development of a palaeothermometer from speleothem carbonate has been something of a ‘holy grail’ for palaeoclimate scientists over the last 50 or more years.
Crawling our way into the Llanio cave system, pushing our bags and all our sampling kit in front of us. BGS © UKRI.
The entrance to Llanio involves a flat-out crawl for several metres before some more small passages lead into the larger sections of the cave, where our water and speleothem sampling takes place. This spring, the crawl was made even worse than normal as the entrance had numerous large spiders in residence and the remains of some unidentifiable animal that we had to crawl over on both the way in and way out of the cave!
Inside the caves
Once we entered the cave, we had an excellent and productive research trip. We were able to collect numerous water samples and extract the phosphate from them using an in-cave chemical extraction method. The data from these samples will be compared to what we would expect at the known cave temperature. We also collected some already-broken calcite, which we will dissolve later back in the BGS Stable Isotope Facility.
Peter undertaking some chemistry measurements from the drip waters we are collecting as they percolate into the cave. BGS © UKRI.
Further work
All these samples will be collated with samples that have been sent to us from collaborators from around the world, to see if we can use our new method to develop a reliable cave palaeothermometer in the BGS laboratories.
About the author
Dr Andrew Smith
Dr Andrew Smith
Isotope geochemist
Relative topics
Dynamics of land-to-lake transfers in the Lake Victoria Basin
09/12/2024
In June 2024, a UK/Kenya research team shared research findings from a collaborative, four-year field and experimental programme within Kenya.
Prehistoric power: 250-million-year-old rocks could contain secrets to net zero future
05/12/2024
BGS has completed a comprehensive scan of Mercia Mudstone rocks that could hold geological secrets of the UK’s past and provide a boost for net zero.
The challenge of assessing the UK economy’s dependence on mineral supply
28/11/2024
Critical, essential, or just plain important? Dr Gavin Mudd, director of the Critical Minerals Intelligence Centre, discusses the findings and new methodology featured in the 2024 UK Criticality Assessment.
UK 2024 Criticality Assessment published
28/11/2024
The latest UK Criticality Assessment, produced by the UK Critical Minerals Intelligence Centre, shows that growing diversification brings an increasing vulnerability in terms of disruption to supply.
Criticality Assessment 2024 launch webinar
Event on 28/11/2024
A special live webinar with the team from the Critical Minerals Intelligence Centre to accompany the launch the latest UK Criticality Assessment. A recording is now available to watch online
UK–Philippine partnership to help tackle the challenges of future water security in the Philippines
07/11/2024
New ‘hydrological hub’ to foster research and provide essential national water management datasets and tools.
Next stage of funding awarded for project on hydrogen storage potential in the East Midlands
17/10/2024
BGS will conduct essential studies on hydrogen behaviour in the subsurface to predict, measure and monitor underground hydrogen storage.
World-class facility creates new opportunities for geothermal energy in Cheshire
10/10/2024
The £8.3 million underground observatory will enhance the UK’s knowledge on the clean energy required to decarbonise heating.
BGS collaborates with Icelandic colleagues to assess windfarm suitability
03/10/2024
Iceland’s offshore geology, geomorphology and climate present all the elements required for renewable energy resources.
Seabed geology data: stakeholder consultation
25/09/2024
BGS is seeking stakeholder feedback as part of a new Crown Estate-led initiative to improve understanding of national-scale seabed geology requirements
Local MP checks in on development of new geothermal ‘living laboratory’ in Nottinghamshire
19/09/2024
BGS has reached the halfway mark on its ambitious ground-source heat pump project at its headquarters in Keyworth, Nottinghamshire.
Mining sand sustainably in The Gambia
17/09/2024
BGS geologists Tom Bide and Clive Mitchell travelled to The Gambia as part of our ongoing work aiming to reduce the impact of sand mining.