Latest news

Appointments |  PhD's awarded | Publications | Media | Grants & Awards | Conferences


Dr Angela Lamb: Honourary Research Fellow – December 2014

Congratulations to Dr Angela Lamb on her appointment as Honorary Research Fellow within the Department of Archaeology, University of Nottingham. Angela's appointment is due to her role in heading stable isotope-archaeology collaborations within the Centre for Environmental Geochemistry and her research with Dr Naomi Sykes and Dr Holly Miller on the AHRC grant: Changing Scientific and Cultural Perspectives on Human-Chicken Interactions.

Dr Angela Lamb

Dr Jonathan Dean: Stable Isotope Apprentice – January 2014

Jonathan Dean has recently joined NIGL for 2 years as an Isotope Apprentice, and will be working on a variety of projects in the Stable Isotope Group. He was previously based in the School of Geography, University of Nottingham, where his PhD research focused on oxygen isotope analysis of carbonates and diatoms and uranium-thorium dating of lake sediments from Nar Gölü in central Turkey.

Dr Jonathan Dean

Professor Melanie Leng to join major science review panel – October 2013

Melanie will join the NERC Peer Review College (NERC PRC) as a Core Panel Member from 1st January 2014. The Core panel members have lead responsibility for attending moderating Panel meetings to ensure consistency within and between different Panel areas and funding schemes.

Professor Melanie Leng

Dr Sarah Bennett: Stable Isotope Research Geochemist – May 2013

Sarah joins NIGL to carry out research in areas of hydrochemistry, pollution studies and surficial and solid earth geochemistry. Sarah’s previous research focussed on the chemistry and biology of deep-sea hydrothermal systems. She joins us from California where she carried out two post docs, one in microbiology at the University of Southern California and one in geochemistry at the NASA Jet Propulsion Laboratory. She carried out her PhD research at the National Oceanography Centre, Southampton.

Dr Sarah Bennett

Dr Andrea Snelling: Isotope Apprentice – 2013

Andrea Snelling joins NIGL as an isotope apprentice to work on stable isotope analysis and mass spectrometry on a variety of projects.

Dr Andrea Snelling

Top of page

PhD's awarded

September 2014 – Congratulations to Nicola Clark on her PhD entitled: A molluscan record of Late Cenozoic climate and palaeoseasonality from Antarctica and South America.

Shallow marine late Neogene and Quaternary sedimentary deposits around coastal Antarctica and South America contain abundant fossil bivalves, but these have rarely been utilised for palaeoclimate work. Due to their incremental growth, bivalves contain a wealth of information relating to the environment they were living in, including temperature (using δ18O) and productivity (using δ13C). A repeatable method of assessing the preservational state of fossil bivalves using a combination of techniques has been developed to ensure only pristine material is analysed for stable isotopes. These include inspection of the lamellar structure under an optical microscope, observation of luminescence using cathodoluminescence and identification of internal crystal structure using scanning electron microscopy. A targeted study of modern pectinid, cardiid and hiatellid bivalves confirm their suitability for reconstructing sea surface temperatures (SSTs), although in the case of hiatellids an understanding of the local environment is essential for an accurate interpretation of oxygen isotope records. Overall this study emphasises the importance of developing new

climate proxies that identify seasonal variation, and which can be used in conjunction with other environmental proxies to provide detailed palaeoclimate data for little studied Neogene successions of the coastal zones of Antarctica and the south-eastern Pacific.

Nicola Clark

Nicola was supervised by Prof Mark Williams at Leicester and at the BGS by Prof Melanie Leng.

June 2014 – Well done to Andi Smith on the successful defence of his PhD thesis: Speleothem Climate Capture – A Holocene Reconstruction of Northern Iberian Climate and Environmental Change.

An extensive 4 year cave monitoring program has been undertaken at Asiul Cave, a previously unstudied site in Cantabria (Spain). Monitoring indicates that this cave has the potential for long term speleothem development and that stalagmites are ideal for the reconstruction of palaeoclimatic conditions, including importantly palaeorainfall amount reconstruction. Two speleothem samples were therefore removed from the cave and analysed for a suite of geochemical proxies. Coeval oxygen isotope records from Asiul Cave indicate that northern Iberia has experienced considerable deviations in rainfall during the last 12,500 years. These high resolution records are strongly coupled with changes in other regionally important climate archives, helping to add to our understanding of northern Iberian climate evolution. The Asiul speleothem records however, go beyond explaining local changes in environmental conditions by exhibiting a strong coupling between atmospheric conditions, in the form of the North Atlantic Oscillation (NAO) and North Atlantic Ocean circulation. These speleothem archives indicate that the NAO controls not only the positioning of atmospheric storm tracks throughout Europe but through interactions with the surface layer of the ocean can cause major changes in oceanic circulation. These NAO controlled changes in North Atlantic Ocean circulation have been shown to cause significant cooling within the northern North Atlantic and the southerly transport of ice rafted debris, with a millennial periodicity of ~1500 years. The Asiul cave speleothem record is one of the first convincing archives of a millennial scale NAO system which has the capacity to force changes in oceanic

circulation. These speleothems also act to extend existing archives of the NAO back into the Younger Dryas; in doing so the Asiul records challenge our current understanding of NAO dynamics and the exact timing of initial NAO development.

Andi Smith

Andi was supervised by Dr Peter Wynn and Prof Phil Barker at Lancaster University and Prof Melanie Leng and Dr Steve Noble at the BGS.

March 2014 – Congratulations to Annemarie Valentine on successfully defending her PhD thesis: An investigation into the seasonality of the Pliocene southern North Sea Basin: a sclerochronological approach.

The Pliocene world c. 5.3 Ma to c. 2.58 Ma exhibited a relatively stable climate with a warmer global mean surface temperature than present-day by ~2 °C to 3 °C, and palaeoclimate analysis from this interval is used to understand climate drivers in 'warmer world'. Previous oxygen isotope thermometry investigations of Pliocene southern North Sea Basin (SNSB) Aequipecten opercularis from the Coralline Crag Formation in Suffolk, UK repeatedly reveal evidence of a cold-temperate climate regime. Contrastingly, other biological proxies record a warm-temperate/sub-tropical regime. This investigation concentrated on oxygen, carbon and microgrowth increment widths (MIWS) of fossil shell material from Pliocene SNSB spanning an interval of~4.4 Ma to ~2.5 Ma. The study sites included shallow marine Pliocene formations from the western and eastern SNSB, the Ramsholt Member of the Coralline Crag Formation, Suffolk UK, and the Luchtbal Sands and Oorderen Sands Members of the Lillo Formation, Belgium, and the Oosterhout Formation in the Netherlands. Oxygen isotopic palaeotemperature results showed cooler summer temperatures than presently in the SNSB, which were reflective of a cool-temperate regime. There was no evidence of warm-temperate or sub-tropical summer palaeotemperatures in the Pliocene SNSB as suggested by other planktonic proxies. This investigation discussed the possible causal factors for the cooler – than– expected winter and summer palaeotemperatures in the 'warmer' Pliocene world as recorded by this proxy. Discrepancies between the cool summer benthic palaeotemperatures from the bivalves and the warmer sub-tropical or warm-temperate summer palaeotemperature estimations from planktonic biological proxies was rectified by the application of a theoretical summer stratification factor (SSF). However, rectifying the discrepancies between cooler (cold-temperate) benthic winter palaeotemperatures and the warmer

winter palaeotemperatures from other proxies was difficult because stratification does not occur during the winter. Dormancy behaviours in the warm– temperate – sub–tropical organisms was proposed as a suitable mechanism to allow their coexistence with the cool-tolerant bivalves, which were able to grow and feed underneath the thermocline during the summer months. Therefore, the investigation showed how the Pliocene SNSB exhibited a greater seasonality than occurs presently in the SNSB. The driver for the cooler winter temperatures in the Pliocene SNSB was not identified. Localised explanations including continental wind effects, interannual variations in MOC strength, and increased storm activity in the winter bringing cooler water into the SNSB were all suggested as potential drivers. Global features of climate including interglacial/glacial cycles and orbital forcing effects were factors also proposed for the overall mixed palaeotemperature signal in the Pliocene SNSB.

AnneMarie Valentine

Annemarie was supervised at University of Derby by Dr Andy Johnson and by Prof Melanie Leng at the BGS.

March 2014 – Congratulations to Hayley Manners on the successful defence of her thesis: A Multi-Proxy Study of the Palaeocene - Eocene Thermal Maximum in Northern Spain.

At the boundary between the Palaeocene and Eocene epochs (ca. 56 Ma) a significant global warming event, termed the Palaeocene-Eocene Thermal Maximum (PETM), occurred. Records of this event are characterised by a negative carbon isotope excursion (CIE) which has been associated with the release of thousands of petagrams of isotopically light carbon into the ocean-atmosphere system, initiating changes in the carbon cycle, the climate system, ocean chemistry and the marine and continental ecosystems. The amount of isotopically light carbon that was required to cause the event, its source and the rapidity of its release are, however, are still debated. This study uses δ13CTOC, δ13Cn-alkane, δ13CCARB and palynological data to evaluate the PETM CIE in terms of the magnitude of the CIE in both continental and marine settings, rapidity of release and drawdown of carbon, and mobilisation of different organic matter (OM) pools as a response to the climate change. The sections studied span a continental to marine transect in northern Spain. This represents the first organic geochemical study of these PETM sections, one of the first comparisons of CIE magnitude between continental and marine sections within the same sediment routing system, and one of the first comparisons of the same OM proxies within different depositional environments. The data suggest that different OM pools were mobilised in response to the PETM, with reworking of older material, soil residence times, and contemporaneous vegetation all contributing. CIE profile shapes predominantly suggest a rapid onset and recovery from the event. The magnitude of the CIE was also assessed. The current resolution of the data suggests that the differences between continental and marine CIE magnitudes could be minimal within a single sediment routing system, perhaps establishing a realistic CIE magnitude for the PETM, for use in future modelling scenarios.

Hayley Manners

Hayley’s main supervisor was Dr Stephen Grimes (Plymouth) and Prof Melanie Leng at BGS.

March 2014 – Congratulations to Jonathan Dean who gained his PhD entitled: Stable Isotope Analysis and U-Th Dating of Late Glacial and Holocene Lacustrine Sediments from Central Turkey.

Water is a politically sensitive resource in the Near East and water stress is increasing. It is therefore vital that there is a strong understanding of past hydrological variability, so that the drivers of change can be better understood, and so that the links between the palaeoclimate and archaeological records in this key region in the development of human civilisation can be investigated. To be of most use, this requires high resolution records and a good understanding of palaeoseasonality. A sediment sequence spanning ~14,000 years was retrieved from Nar Gölü, a lake in central Turkey. My thesis focussed in particular on oxygen isotope analysis of carbonates and comparing δ18Ocarbonate and δ18Odiatom data in order to examine palaeoseasonality. Due to the high resolution δ18Ocarbonate data, it was possible to show that the rapidity of the Younger Dryas to Holocene transition at Nar Gölü was similar to that seen in North Atlantic records and that centennial scale arid events in the Holocene seem to occur at the time of cold periods in the North Atlantic. Taken together, this suggests a strong teleconnection between the two regions. However, the longer duration of the aridity peaks ~9,300 and ~8,200 years BP at Nar Gölü, compared with the more discrete cooling events at this time in the North Atlantic, suggest that there are additional controls on Near East hydroclimate. There is a multi-millennial scale trend of increasing δ18Ocarbonate values from the early to late Holocene. This ‘Mid Holocene Transition’ has previously been identified in the Near East, however here it is demonstrated that water balance and not a shift in the seasonality of precipitation was the primary cause. Finally, for the first time, the stability of Near East climate in the

early Holocene is robustly demonstrated, suggesting that this could have been a key enabler of the development of agriculture at this time.

Jon was supervised at University of Nottingham by Dr Matthew Jones and Prof Sarah Metcalfe, at NIGL he was supported by Dr Stephen Noble and Prof Melanie Leng

Jon Dean

December 2013 – congratulations to Sven Könitzer who was granted a doctorate for his PhD research entitled: Primary biological controls on UK Lower Namurian shale gas prospectivity: A step towards understanding a major potential UK unconventional gas resource.

Sven’s research is the first to analyse the abundance and type of organic matter preserved in deeper-water mudstones deposited in a Late Mississippian UK basin alongside a detailed sedimentological study to determine the key depositional processes and the palaeoenvironment. This study is a key step in understanding where, and why, organic matter is concentrated in fine-grained sedimentary rocks. Mudstones of this age, deposited across central and northern England, are known oil and gas source rocks and are currently the focus of attention for onshore shale gas exploration. Shale gas is formed from organic matter present during maturation and is mostly retained in the same rock formation.

Sven was supervised by Prof Sarah Davies (Leicester) and Prof Mike Stephenson, Prof Melanie Leng, and Dr Chris Vane at the BGS

More information

Sven Könitzer

Top of page


The latest NIGL Annual Report can be downloaded. This section highlights some of our high-impact papers as they go to press. A full list of NERC staff publications and outputs can be found in the NERC Open Research Archive (NORA)

Journal of Paleolimnology – December 2014

Lake Prespa, in the Balkans, contains an important palaeo-archive in a key location for understanding Quaternary climate variability in the transition between Mediterranean and central European climate zones. Previous palaeoenvironmental research on sediment cores indicates that the lake is highly sensitive to climate change and that diatoms are likely to be strong palaeohydrological proxies. Here, we present new results from diatom analysis of a ca. 91 ka sequence, core Co1215, which spans the time from the end of the last interglacial to the present. Fluctuations in the diatom data were driven primarily by changes in lake level, as a function of shifts in moisture availability. Warmer interglacial (MIS 5, MIS 1) and interstadial (MIS 3) phases exhibit higher lake levels in spite of enhanced evaporative concentration, underlining the importance of changes in precipitation regimes over time. Low lake levels during glacial phases indicate extreme aridity, common to all Mediterranean lakes. Evidence for fluctuations in trophic status is linked, in part, to lake-level change, but also reflects nutrient enrichment from catchment processes. MIS 5a is characterized by the highest lake productivity in the sequence, but low lake levels, which are ascribed primarily to very low precipitation.

Journal of Paleolimnology

On a suborbital timescale, the diatoms provide evidence for correlation to the millennial-scale variability recorded in the Greenland oxygen isotope records and clearly reflect the impact of the Heinrich H6, H5 and H3–1 ice-rafting events, suggesting the dominant influence of North Atlantic forcing in this region. Although the highest-amplitude shift in the diatom assemblages occurs during the time of H4 (40–38 ka), it may be superimposed upon the impact of the 39.28 cal ka BP Campanian Ignimbrite volcanic eruption. Diatoms from Lake Prespa core Co1215 display the first strong evidence for the impact of Italian volcanic activity on lacustrine biota in this region. Results emphasize the complexity of diatom response thresholds in different studies across the region. In the case of Lake Prespa, the results highlight the important role of precipitation for maintaining the hydrological balance of the lake, and indirectly, its biodiversity.

Cvetkoska, A., Levkov, Z., Reed, J.M., Wagner, B., Panagiotopoulos, K., Leng, M.J., Lacey, J.H. 2014. Quaternary climate change and Heinrich Events in the southern Balkans: Lake Prespa diatom palaeolimnology from the last interglacial to present. Journal of Paleolimnology.

More information

Journal of Hydrology – November 2014

Palaeo-hydrological interpretations of lake sediment proxies can benefit from a robust understanding of the modern lake environment. In this study, we use Nar Gölü, a non-outlet, monomictic maar lake in central Turkey, as a field site for a natural experiment using observations and measurements over a 17-year monitoring period (1997-2014). We compare lake water and sediment trap data to isotopic, chemical and biotic proxies preserved in its varved sediments. Nar Gölü underwent a 3 m lake-level fall between 2000 and 2010. δ18Olakewater is correlated with this lake-level fall, responding to the change in water balance. Endogenic carbonate is shown to precipitate in isotopic equilibrium with lake water and there is a strong relationship between δ18Olakewater and δ18Ocarbonate, which suggests the water balance signal is accurately recorded in the sediment isotope record. Over the same period, sedimentary diatom assemblages also responded, and conductivity inferred from diatoms showed a rise. Shifts in carbonate mineralogy and elemental chemistry in the sediment

Journal of Hydrology

record through this decade were also recorded. Intra-annual changes in δ18Olakewater and lake water chemistry are used to demonstrate the seasonal variability of the system and the influence this may have on the interpretation of δ18Ocarbonate. We use these relationships to help interpret the sedimentary record of changing lake hydrology over the last 1,725 years. Nar Gölü has provided an opportunity to test critically the chain of connection from present to past, and its sedimentary record offers an archive of decadal- to centennial-scale hydro-climatic change.

Dean, J.R., Eastwood, W.J., Roberts, C.N., Jones, M.D., Yiğitbaşıoğlu, H., Allcock, S.L., Woodbridge, J., Metcalfe, S.E., Leng, M.J., In press. Tracking the hydro-climatic signal from lake to sediment: a field study from central Turkey. Journal of Hydrology.

More information

Climate of the Past – October 2014

Oxygen isotope analyses of different size fractions of Pliocene diatoms (δ18Odiatom) from the Bering Sea show no evidence of an isotope offset and support the use of bulk diatom species samples for palaeoceanographic reconstructions. Additional samples containing concentrations of sponge spicules produce δ18O values several per mille (‰) lower than δ18Odiatom with a calculated mean offset of 3.9‰ ± 1.5. This difference is significantly greater than modern-day variations in water δ18O through the regional water column. Despite the potential for oxygen isotope disequilibrium within δ18Osponge, there appears to be some similarity between δ18Osponge

Climate of the Past

and a global stacked benthic δ18Oforam record. This highlights the potential for δ18Osponge in palaeoenvironmental research at sites where carbonates are not readily preserved.

Snelling, A. M., Swann, G. E. A., Pike, J., and Leng, M. J. Pliocene diatom and sponge spicule oxygen isotope ratios from the Bering Sea: isotopic offsets and future directions, Clim. Past, 10, 1837-1842, doi:10.5194/cp-10-1837-2014, 2014.

More information

Geology – September 2014

Late Cenozoic climate history in Africa was punctuated by episodes of variability, characterized by the appearance and disappearance of large freshwater lakes within the East African Rift Valley. In the Baringo-Bogoria basin, a well-dated sequence of diatomites and fluviolacustrine sediments documents the precessionally forced cycling of an extensive lake system between 2.70 Ma and 2.55 Ma. One diatomite unit was studied, using the oxygen isotope composition of diatom silica combined with X–ray fluorescence spectrometry and taxonomic assemblage changes, to explore the nature of climate variability during this interval. Data reveal a rapid onset and gradual decline of deepwater lake conditions, which exhibit millennial-scale cyclicity of 1400–1700 yr, similar to late Quaternary Dansgaard-Oeschger events.


These cycles are thought to reflect enhanced precipitation coincident with increased monsoonal strength, suggesting the existence of a teleconnection between the high latitudes and East Africa during this period. Such climatic variability could have affected faunal and floral evolution at the time.

Wilson, K.E., Maslin, M.A., Leng, M.J., Kingston, J.D., Deino, A.L., Edgar, R.K., Mackay, A.W. 2014. East African lake evidence for Pliocene millennial-scale climate variability. Geology.

More information

Journal of Quaternary Science – August 2014

Analysis of the oxygen isotope composition of diatom silica is a commonly used tool for palaeoclimate reconstruction that recent studies have demonstrated may be complicated by the presence of non-diatom detrital material. Such contamination can mask any true climate-driven signal, leading to spurious results. Analysis of the 2.6-Ma Barsemoi diatomites from the East African Rift Valley highlights the presence of both tephra and clay in purified samples. Here we present a new method for assessing the relative contribution and geochemical composition of contamination components where sedimentary samples may be affected by more than one type of contamination. This approach shows that the incorporation of analytical techniques, such as X-ray fluorescence spectrometry, coupled with statistical modelling,

Journal of Quaternary Science

can be used to develop a three end-member model to successfully resolve climate-driven changes in δ18Odiatom. Mass-balance corrections made to δ18Odiatom data demonstrate the importance of adopting quantitative geochemical analysis in tandem with the δ18O analysis of biogenic silica, to obtain accurate and meaningful results for palaeoclimate reconstruction.

Wilson, K.E., Leng, M.J., Mackay, A.W. 2014. The use of multivariate statistics to resolve multiple contamination signals in the oxygen isotope analysis of biogenic silica. Journal of Quaternary Science

More information

Journal of Archaeological Science – August 2014

The discovery of the mortal remains of King Richard III provide an opportunity to learn more about his lifestyle, including his origins and movements and his dietary history; particularly focussing on the changes that Kingship brought. We analysed bioapatite and collagen from sections of two teeth which formed during Richard's childhood and early adolescence, and from two bones: the femur (which averages long-term conditions), and the rib (which remodels faster and represents the last few years of life). We applied multi element isotope techniques to reconstruct a full life history. The isotopes initially concur with Richard's known origins in Northamptonshire but suggest that he had moved out of eastern England by age seven, and resided further west, possibly the Welsh Marches. In terms of his diet, there is a significant shift in the nitrogen, but not carbon isotope values, towards the end of his life, which we suggest could be explained by an increase

Special publication 395

in consumption of luxury items such as game birds and freshwater fish. His oxygen isotope values also rise towards the end of his life and as we know he did not relocate during this time, we suggest the changes could be brought about by increased wine consumption. This is the first suggestion of wine affecting the oxygen isotope composition of an individual and thus has wider implications for isotope-based palaeodietary and migration reconstructions.

Lamb, A.L., Evans, J.E., Buckley, R., Appleby, J. 2014. Multi-isotope analysis demonstrates significant lifestyle changes in King Richard III. Journal of Archaeological Science, 48, 5–14.

More information

Archaeofauna – August 2014

The exploitation of marine molluscs by Mediterranean hunter-gatherers increased from the Upper Palaeolithic onwards, although their role in subsistence has rarely been investigated fully. An ideal area to address this issue is the archipelago of the Egadi Islands, most of which were isolated by Post-Glacial sea level rise. Here we report on the results of the study of the mollusc assemblage recovered during the 1972 excavations at Grotta d'Oriente, a cave on Favignana, occupied from the Late Pleistocene to the middle Holocene. Marine molluscs, including principally rocky shore intertidal gastropods (Patella and Osilinus), were taken to the cave for consumption throughout its occupation, sporadically in the early Mesolithic, but more frequently and throughout the year in the late Mesolithic and early Neolithic. Progressive isolation resulted in intensification of shellfish exploitation, but not, however, in

Special publication 395

long-term over-exploitation of all intertidal marine gastropods, despite their vulnerability to human predation. The archaeozoological and isotopic data suggest that shellfish were a useful source of protein for the occupants of Grotta d'Oriente, but that the main role of marine molluscs was probably to provide nutrients not readily available in the terrestrial foods which constituted the bulk of the diet.

Marcello, M., Thomas, K., Crema, E.R., Leng, M.J. 2014. A matter of taste? Mode and periodicity of marine mollusc exploitation on the Mediterranean island of Favignana (Egadi Islands, Italy) during its isolation in the early Holocene. Archaeofauna, 23, 133-147.

International Journal of Earth Sciences – August 2014

Lake Ohrid (Macedonia/Albania) is the oldest extant lake in Europe and exhibits an outstanding degree of endemic biodiversity. Here, we provide new high–resolution stable isotope and geochemical data from a 10 m core (Co1262) through the Late Glacial to Holocene and discuss past climate and lake hydrology (TIC, δ13Ccalcite, δ18Ocalcite) as well as the terrestrial and aquatic vegetation response to climate (TOC, TOC/N, δ13Corganic, Rock Eval pyrolysis). The data identifies 3 main zones: (1) the Late Glacial–Holocene transition represented by low TIC and TOC contents, (2) the early to mid–Holocene characterised by high TOC and increasing TOC/N and (3) the Late Holocene–Present which shows a marked decrease in TIC and TOC. In general, an overall trend of increasing δ18Ocalcite from 9 ka to present suggests progressive aridification through the Holocene, consistent with previous records from Lake Ohrid and the wider Mediterranean region. Several proxies show commensurate excursions that imply the impact of short-term climate oscillations, such as the 8.2 ka event and the Little Ice Age. This is the bes–dated and highest resolution archive

International Journal of Earth Sciences – August 2014

of past Late Glacial and Holocene climate from Lake Ohrid and confirms the overriding influence of the North Atlantic in the north–eastern Mediterranean. The data presented set the context for the International Continental scientific Drilling Program Scientific Collaboration On Past Speciation Conditions in Lake Ohrid project cores recovered in spring–summer 2013, potentially dating back into the Lower Pleistocene, and will act as a recent calibration to reconstruct climate and hydrology over the entire lake history.

Lacey, J.H., Francke, A., Leng, M.J., Vane, C.H., Wagner, B. 2014. A high resolution Late Glacial to Holocene record of environmental change in the Mediterranean from Lake Ohrid (Macedonia/Albania). International Journal of Earth Sciences. DOI 10.1007/s00531-014-1033-6.

More information

Geology – July 2014

The Paleocene–Eocene Thermal Maximum (PETM), ca. 56 Ma, was a major global environmental perturbation attributed to a rapid rise in the concentration of greenhouse gases in the atmosphere. Geochemical records of tropical sea-surface temperatures (SSTs) from the PETM are rare and are typically affected by post-depositional diagenesis. To circumvent this issue, we have analyzed oxygen isotope ratios (δ18O) of single specimens of exceptionally well-preserved planktonic foraminifera from the PETM in Tanzania (δ19°S paleolatitude), which yield extremely low δ18O, down to <–5‰. After accounting for changes in seawater chemistry and pH, we estimate from the foraminifer δ18O that tropical SSTs rose by >3 °C during the PETM and may


have exceeded 40 °C. Calcareous plankton are absent from a large part of the Tanzania PETM record; extreme environmental change may have temporarily caused foraminiferal exclusion.

Aze, T., Pearson, P.N., Dickson, A.J., Badger, M.P.S., Bown, P.R., Pancost, R.D., Gibbs, S.J., Huber, B.T., Leng, M.J., Coe, A.L., Cohen, A.S., and Foster, G.L. 2014. Extreme warming of tropical waters during the Paleocene–Eocene Thermal Maximu. Geology, 42.

More information

Science of the Total Environment – July 2014

Peri-urban floodplains are an important interface between developed land and the aquatic environment and may act as a source or sink for contaminants moving from urban areas towards surface water courses. With increasing pressure from urban development the functioning of floodplains is coming under greater scrutiny. A number of peri-urban sites have been found to be populated with legacy landfills which could potentially cause pollution of adjacent river bodies. Here, a peri-urban floodplain adjoining the city of Oxford, UK, with the River Thames has been investigated over a period of three years through repeated sampling of groundwaters from existing and specially constructed piezometers. A nearby landfill has been found to have imprinted a strong signal on the groundwater with particularly high concentrations of ammonium and generally low concentrations of nitrate and dissolved oxygen. An intensive study of nitrogen dynamics through the use of N-species chemistry, nitrogen isotopes and dissolved nitrous oxide reveals that there is little or no denitrification in the majority of the main landfill plume, and neither is the ammonium significantly

Special publication 395

retarded by sorption to the aquifer sediments. A simple model reveals that up to 15% of the ammonium loading at the study site and over the length of the reach could increase in-stream concentrations by nearly 40%. Catchment management plans that encompass floodplains in the peri-urban environment need to take into account the likely risk to groundwater and surface water quality that these environments pose.

Gooddy, D.C., Macdonald, D.M.J., Lapworth, D.J., Bennett, S.A., Griffiths, K.J. Nitrogen sources, transport and processing in peri-urban floodplains, Science of the Total Environment 494-495 (2014) 28-38.

More information

Anthropocene Review – July 2014

We consider whether the Anthropocene is recorded in the isotope geochemistry of the atmosphere, sediments, plants and ice cores, and the time frame during which any changes are recorded, presenting examples from the literature. Carbon and nitrogen isotope ratios have become more depleted since the 19th century, with the rate of change accelerating after ∼AD 1950, linked to increased emissions from fossil fuel consumption and increased production of fertiliser. Lead isotope ratios demonstrate human pollution histories several millennia into the past, while sulphur isotopes can be used to trace the sources of acid rain.

Special publication 395

Radioisotopes have been detectable across the planet since the 1950s because of atmospheric nuclear bomb tests and can be used as a stratigraphic marker. We find there is isotopic evidence of widespread human impact on the global environment, but different isotopes have registered changes at different times and at different rates.

Dean, J.R, Leng, M.J., Mackay, A.W. 2014. Is there an isotopic signature of the Anthropocene? The Anthropocene Review.

More information

Stratigraphical Basis for the Anthropocene – June 2014

Humankind has pervasively influenced the Earth’s atmosphere, biosphere, geosphere, hydrosphere and cryosphere, arguably to the point of fashioning a new geological epoch, the Anthropocene. To constrain the Anthropocene as a potential formal unit within the Geological Time Scale, a spectrum of indicators of anthropogenically-induced environmental change is considered, and shown as stratigraphical signals that may be used to characterize an Anthropocene unit, and to recognize its base. This volume describes a range of evidence that may help to define this potential new time unit and details key signatures that could be used in its definition. These signatures include lithostratigraphical (novel deposits, minerals and

Special publication 395

mineral magnetism), biostratigraphical (macro- and micro-palaeontological successions and human-induced trace fossils) and chemostratigraphical(organic, inorganic and radiogenic signatures in deposits, speleothems and ice and volcanic eruptions). We include, finally, the suggestion that humans have created a further sphere, the technosphere, that drives global change.

C.N. Waters, J.A. Zalasiewicz, M. Williams, M.A. Ellis and A.M. Snelling. 2014. A Stratigraphical Basis for the Anthropocene. Special Publication 395.

More information

International Journal of Earth Sciences – May 2014

Lake Ohrid (Macedonia/Albania) is the oldest extant lake in Europe and exhibits an outstanding degree of endemic biodiversity. Here, we provide new high-resolution stable isotope and geochemical data from a 10 m core (Co1262) through the Late Glacial to Holocene and discuss past climate and lake hydrology (TIC, δ13Ccalcite, δ18Ocalcite) as well as the terrestrial and aquatic vegetation response to climate (TOC, TOC/N, δ13Corganic, Rock Eval pyrolysis). The data identifies 3 main zones: (1) the Late Glacial–Holocene transition represented by low TIC and TOC contents, (2) the early to mid-Holocene characterised by high TOC and increasing TOC/N and (3) the Late Holocene–Present which shows a marked decrease in TIC and TOC. In general, an overall trend of increasing δ18Ocalcite from 9 ka to present suggests progressive aridification through the Holocene, consistent with previous records from Lake Ohrid and the wider Mediterranean region. Several proxies show commensurate excursions that imply the impact of

International Journal of Earth Sciences

short-term climate oscillations, such as the 8.2 ka event and the Little Ice Age. This is the best-dated and highest resolution archive of past Late Glacial and Holoce climate from Lake Ohrid and confirms the overriding influence of the North Atlantic in the north-eastern Mediterranean. The data presented set the context for the International Continental scientific Drilling Program Scientific Collaboration On Past Speciation Conditions in Lake Ohrid project cores recovered in spring–summer 2013, potentially dating back into the Lower Pleistocene, and will act as a recent calibration to reconstruct climate and hydrology over the entire lake history.

Lacey, J.H., Francke, A., Leng, M.J., Vane, C.H., Wagner, B. 2014. A high–resolution Late Glacial to Holocene record of environmental change in the Mediterranean from Lake Ohrid (Macedonia/Albania). International Journal of Earth Sciences. DOI 10.1007/s00531-014-1033-6.

More information

Journal of Quaternary Science – May 2014

The oxygen isotope composition of diatom silica (δ18Odiatom) is increasingly being used to reconstruct climate from marine and lacustrine sedimentary archives. Although diatoms are assumed to precipitate their frustule in isotopic equilibrium with their surrounding water, it is unclear whether internal processes of a given species affect the fractionation of oxygen between the water and the diatom. We present δ18Odiatom data from two diatom size fractions (3–38 and >38μm) characterized by different species in a sediment core from Heart Lake, Alaska. Differences in δ18Odiatom between the two size fractions varies from 0 to 1.2‰, with a mean offset of 0.01‰ (n=20). Fourier transform infrared spectroscopy confirms our samples consist of pure biogenic silica (SiO2) and δ18Odiatom trends are not driven by contamination. The maximum offset is outside the range of error, but the mean is within analytical error of the

Journal of Quaternary Science

technique (±1.06‰), demonstrating no discernible species-dependent fractionation in δ18Odiatom. We conclude that lacustrine δ18Odiatom measurements offer a reliable and valuable method for reconstructing δ18Owater. Considering the presence of small offsets in our two records, we advise interpreting shifts in δ18Odiatom only where the magnitude of change is greater than the combined analytical error.

Bailey, Hannah L.; Henderson, Andrew C.G.; Sloane, Hilary J.; Snelling, Andrea; Leng, Melanie J.; Kaufman, Darrell S. 2014. The effect of species on lacustrine δ18Odiatom and its implications for palaeoenvironmental reconstructions. Journal of Quaternary Science, 29 (4). 393-400.

More information

Scientific Drilling – May 2014

The Scientific Collaboration on Past Speciation Conditions in Lake Ohrid (SCOPSCO) project is an international research initiative to study the influence of major geological and environmental events on the biological evolution of lake taxa. SCOPSCO drilling campaigns were carried out in 2011 and 2013. In 2011 we used gravity and piston coring at one of the five proposed drill sites, and in 2013 we undertook deep drilling with the Deep Lake Drilling System (DLDS) of Drilling, Observation and Sampling of the Earth's Continental Crust (DOSECC). In April and May 2013, a total of 2100 m sediments were recovered from four drill sites with water depths ranging from 125 to 260 m. The maximum drill depth was 569 m below the lake floor in the centre of the lake. By retrieving overlapping sediment sequences, 95% of the sediment succession was recovered. Initial data from borehole logging, core logging and geochemical measurements indicate that the sediment

Scientific Drilling

succession covers >1.2 million years (Ma) in a quasi-continuous sequence. These early findings suggest that the record from Lake Ohrid will substantially improve the knowledge of long-term environmental change and short-term geological events in the northeastern Mediterranean region, which forms the basis for improving understanding of the influence of major geological and environmental events on the biological evolution of endemic species.

Wagner, B., Wilke, T., Krastel, S., Zanchetta, G., Sulpizio, R., Reicherter, K., Leng, M., Grazhdani, A., Trajanovski, S., Francke A., Lindhorst, K., Cvetkoska, A., Reed, J.M., Zhang, X., Lacey, J.H., Wonik, T., Baumgarten, H., Vogel, H. 2014. The SCOPSCO drilling project recovers more than 1.2 million years of history from Lake Ohrid. Scientific Drilling, 17, 19-29.

Climate of the Past – May 2014

The transboundary Lake Prespa (Albania/former Yugoslav Republic of Macedonia/Greece) has been recognized as a conservation priority wetland. The high biodiversity encountered in the catchment at present points to the refugial character of this mountainous region in the southwestern Balkans. A lake sediment core retrieved from a coring location in the northern part of the lake was investigated through sedimentological, geochemical, and palynological analyses. Based on tephrochronology, radiocarbon and electron spin resonance (ESR) dating, and cross correlation with other Northern Hemisphere records, the age model suggests that the basal part of core Co1215 reaches back to 92 ka cal BP. Here we present the responses of this mid-altitude site (849 m a.s.l.) to climate oscillations during this interval and assess its sensitivity to millennial-scale variability. Endogenic calcite precipitation occurred in marine isotope stages (MIS) 5 and 1 and is synchronous with periods of increased primary production (terrestrial and/or lacustrine). Periods of pronounced phytoplankton blooms (inferred from green algae and dinoflagellate concentrations) are recorded in MIS 5 and MIS 1 and

Climate Of The Past

suggest that the trophic state and lake levels underwent substantial fluctuations. Three major phases of vegetation development are distinguished: the forested phases of MIS 5 and MIS 1 dominated by deciduous trees with higher temperatures and moisture availability, the open landscapes of MIS 3 with significant presence of temperate trees, and the pine-dominated open landscapes of MIS 4 and MIS 2 with lower temperatures and moisture availability. Our findings suggest significant changes in forest cover and landscape openness, as well as in the properties of the vegetation belts (composition and distribution) over the period examined. The study area most likely formed the upper limit of several drought-sensitive trees (temperate tree refugium) at these latitudes in the Mediterranean mountains.

Panagiotopoulos, K., Böhm, A., Leng, M.J., Wagner, B., Schäbitz, F. 2014. Climate variability over the last 92Ka in SW Balkans from analysis of sediments from Lake Prespa. Climate of the Past, 10, 643-660.

Journal Of Archaeological Science – May 2014

Two sets of well-preserved human footprints have been found in tufa sediments in the Cuatrociénegas Basin, NE Mexico, and here we present their U-series dates of 10.55 ± 0.03 ka and 7.24 ± 0.13 ka. The former are the oldest known footprints in Mexico, although their exact location is unknown, the latter form part of a trackway with eleven in situ human footprints. Oxygen (and to a lesser extent) carbon isotope data from the sediments suggest that the tufa with in situ footprints formed during a transition to a wetter (less arid) period, while pollen evidence indicates the basin floor presence of pecan (Carya) and willow (Salix sp.) before the onset of regional Chihuahuan Desert aridity.

Journal Of Archaeological Science

These footprints confirm the presence of humans, possibly nomadic hunter–gatherer groups, which persisted until the 18th Century AD.

Feldstead, N.J., Gonzalez, S., Huddart, D., Noble, S.R., Hoffmann, D.L., Metcalfe, S.E., Leng, M.J., Albert, B.M., Pike, A.W.G., Gonzalez-Gonzalez, A., Jimenez-Lopez, J, C. 2014. Holocene-aged human footprints from the Cuatrocienegas Basin, NE Mexico. Journal of Archaeological Sciences, 42, 250-259.

Journal of Sedimentary Research – March 2014

Deep-water mudstones from ancient epicontinental settings are significant repositories for organic matter, but the detailed temporal variations of, and controls on, the abundance and type of organic matter (OM) is little studied. Using micro-petrographic and geochemical data from late Mississippian mudstones of the Widmerpool Gulf, UK, the processes that delivered fine-grained sediment to this basin during a glacioeustatic sea-level cycle are interpreted from detailed lithofacies analysis. Seven primary lithofacies are identified from core, which show specific and systematic variations in total organic carbon (TOC) content and bulk carbon isotope composition of organic material (δ13Corg). During sea-level highstands, thin-bedded carbonate-bearing mudstones are the dominant facies deposited, contain up to 6.6% TOC (average 4.6±1.3%), and have mean δ13Corg of &nda28.5±0.9‰. During phases of lower sea level, thin-bedded silt-bearing clay-rich mudstones with up to 4.1% TOC (average 2.3±0.8%; mean δ13Corg: –28.2±1.0‰) were interbedded with more organic-lean graded silt-bearing mudstones and sand-bearing silt-rich mudstones (average TOC: 1.7±0.6%) derived from turbidity currents. The latter (mean δ13Corg: –26.2±0.7‰) are closely linked to significant proportions of terrestrial plant material, while some rare plant debris- and sand-bearing mudstones produced from debris flows have more than 7.0% TOC and δ≥–26.0‰.

Journal of Sedimentary Research

The δ13C values of wood fragments ranged from –27.1‰ to –24.0‰ and therefore the δ13Corg is interpreted as a function of the ratio of marine and terrestrial organic matter. More negative values in the carbonate-bearing and the clay-rich mudstones indicate marine planktonic algae whereas the least negative values reflect greater contribution of terrestrial plant material. The data suggest that the marine conditions prevailed and supported marine planktonic algae throughout different sea-level stages. Marine OM was delivered to the sea floor by continuous hemipelagic settling whereas terrestrial OM was delivered by sediment density flows. Variations in bioproductivity and dilution by siliciclastics influenced the burial rate of marine OM. Organic-rich mudstones preserved in these marine basins are potential hydrocarbon source rocks, especially as unconventional (shale gas) reservoirs. Detailed microtextural and compositional analysis coupled with rigorous geochemical parameters as used in this study are important for the understanding of the source-rock potential of basinal mudstones, and of fine-grained organic-rich sediments in general.

Konitzer, S.F., Davies, S.J., Stephensin, M.H., Leng, M.J. 2014. Depositional Controls On Mudstone Lithofacies In A Basinal Setting: Implications for the Delivery of Sedimentary Organic Matter. Journal of Sedimentary Research, 84, 198-214.

More information

Climate of the Past – February 2014

The 74 (75) ka Toba eruption in Sumatra, Indonesia, is considered to be one of the largest volcanic events during the Quaternary. Tephra from the Toba eruption has been found in many terrestrial and marine sedimentary deposits, and acidity peaks related to the eruption have been used to synchronize ice core records from Greenland and Antarctica. Seismic profiles and sedimentological data from Lake Prespa on the Balkan Peninsula, SE Europe, indicate a lake level lowstand at 73.6 ± 7.7 ka based on ESR dating of shells. Tephrostratigraphy, radiocarbon dating and tuning of the total organic carbon content with the NGRIP isotope record, corroborate that the lake level lowstand was a short-term event superimposed on the general cooling trend at the end of MIS 5, most likely at the onset of the Greenland Stadial GS-20. Acknowledging that tectonic events or karst

Climate of the past

processes could have triggered this lake level lowstand, the chronological correspondence between the lowstand and the Toba eruption is intriguing. Therefore a Toba-driven short-term shift to aridity in the Balkan region, leading to lake level changes and triggering spatial expansion events in one of the lake's most abundant benthic species, the carino mussel Dreissena presbensis, cannot be excluded.

Citation: Wagner, B., Leng, M. J., Wilke, T., Böhm, A., Panagiotopoulos, K., Vogel, H., Lacey, J. H., Zanchetta, G., and Sulpizio, R.: Distinct lake level lowstand in Lake Prespa (SE Europe) at the time of the 74 (75) ka Toba eruption, Clim. Past, 10, 261-267, doi:10.5194/cp-10-261-2014, 2014.

More information

Geobiology – January 2014

Iron (Fe) oxidizing bacteria have the potential to produce morphologically unique structures that may be used as biosignatures in geological deposits. One particular example is Mariprofundus ferrooxydans, which produces extracellular twisted ribbon-like stalks consisting of ferrihydrite, co-located with organic and inorganic elements. It is currently thought that M. ferrooxydans excrete and co-precipitate polysaccharides and Fe simultaneously, however the cellular production of these polysaccharides has yet to be confirmed. Here, we report on a time series study that used scanning


transmission X-ray microscopy (STXM) and C 1s and Ca 2p near-edge X-ray adsorption fine structure (NEXAFS) spectroscopy to investigate production of polysaccharides over the growth cycle of M. ferrooxydans.

Sarah A. Bennett, Brandy M. Toner, Roman Barco and Katrina J. Edwards. 2014. Carbon adsorption by Fe oxyhydroxide stalks produced by a lithotrophic iron-oxidizing bacteria. Geobiology DOI:10.1111/gbi.12074

More information

Top of page

NIGL research in the Media

December 2014 – Reading the signals in sediments... by Jonathan Dean

Jonathan Dean has just published a paper in the Journal of Hydrology, where he brought together measurements made at the British Geological Survey over two decades, to better understand how climate change is recorded in lake sediments. Here he discusses why this was such important work...

More information

Nar Gl in April 2014. The lake formed in an old volcano.

November 2014 – South Georgia and ancient algal blooms ... by Rowan Dejardin

South Georgia is a strikingly beautiful, uninhabited island in the Southern Ocean, west of Patagonia and hundreds of miles from any major landmasses. Remote it may be but its ancient algal blooms and sediments potentially hold the key to understanding relationships between the carbon cycle and climate change in the past and, therefore, the future. Rowan Dejardin has just started his PhD within the Centre for Environmental Geochemistry (University of Nottingham and the BGS) and tells us more about his search for South Georgian algal blooms...

More information

South Georgia

November 2014 – Nitrogen and the Anthropocene... by Melanie Leng

Last week BGS hosted a workshop entitled "The Nitrogen Cycle and the Anthropocene". The aim of the workshop was to bring together nitrogen experts from around the UK to discuss the modern day increase in the amount of nitrogen currently being deposited (through atmospheric fall out and as a result of mans' activities on the Earth's surface). The main culprits of this increasing nitrogen are industrial processes, increasing use of fertilisers and combustion of fossil fuels. Here Melanie Leng tells us about the workshop...

More information

The delegates at the Workshop

October 2014 – Caves and Climate Change... by Andi Smith

As we strive to understand modern day climate change and the possible impact humans are having on our environment, many scientists look to the past to provide evidence of natural climate evolution. Andrew Smith is one such scientist. Here he shares how analysing Spanish stalagmites has helped unlock the last 12,500 years of climatic changes as well as large scale rainfall dynamics throughout Europe...

More information

Here I am with some fine speleothem formations
 in Shuttleworth Pot, Yorkshire, UK

August 2014 – Abandoned landfills are pollution UK rivers

Research led by Daren Gooddy, BGS, has identified high levels of ammonium leaking out from a landfill into a river on the outskirts of Oxford. The source of the ammonium was identified with isotopic analysis carried out by NIGL scientist Sarah Bennett...

More information:

Researchers take a sample of water from River Thames at Oxford for analysis. Photograph: Dr Daren Gooddy/NERC

August 2014 – Can isotopes help define the Anthropocene? By Dr Jonathan Dean

The Anthropocene is a term that is increasingly being used to refer to the current interval in geological time in which humans have become a dominant force of global environmental change. It was coined by Prof Eugene Stoermer, a biologist, in the 1980s and popularised in the early 2000s by Prof Paul Crutzen, an atmospheric chemist...

welcome to the Anthropocene

July 2014 – Using carbon isotopes to study Lake Baikal... by Sarah Roberts

Today we're very pleased to share a guest post from Sarah Roberts, a Postgraduate Researcher at the School of Geography, University of Nottingham. Here she introduces her exciting collaborative work, to investigate changes in nutrient fluxes at Lake Baikal, Siberia, with the Baikal research team; Dr. George Swann, Prof. Anson Mackay, Dr. Suzanne McGowan and Dr. Virginia Panizzo (BGS Visiting Research Associates) and BGS staff...

Lake Baikal.jpg

July 2014 – The Ohrid Sequel: Cheshire Mere... by Jack Lacey

Jack Lacey is a familiar face to the blog. Over the last 16 months he's taken us along on amazing fieldwork adventures to Lake Ohrid, drilling through 3 million years of Earth's history and looking for the impacts of volcanic super eruptions using lake sediment records. But this was just phase 1 of his PhD research. Here Jack tells us what's in store for Phase 2 as he works within the Centre for Environmental Geochemistry, a collaboration between the University of Nottingham and the BGS...

European Geosciences Union

June 2014 – Chicken Project gets off the ground

A new research project has begun to examine the history of chickens, involving archaeological records to investigate the history of the world's most widely established livestock species, originally descended from the wild jungle fowl of South East Asia. The project, entitled "Cultural and Scientific Perceptions of Human-Chicken Interactions", was made possible with the help of a £1.94 million grant from the AHRC under the Science In Culture Awards Large Grants call. Researchers from Bournemouth University, as well as the Universities of Durham, Nottingham, Leicester, Roehampton and York, will be examining when and how rapidly domesticated chickens spread across Europe and the history of their exploitation for meat and eggs. Research methods will include stable isotope analysis at the BGS Stable Isotope Facility, in collaboration with the University of Nottingham within The Centre for Environmental Geochemistry...

European Geosciences Union

May 2014 – The mass exodus of geoscientists to Vienna... by Prof Melanie Leng

Every year around this time a European Geosciences Union (EGU) is held in Vienna, Austria. The weeklong conference brings together geoscientists from all over the world to discuss their latest findings in earth, planetary and space sciences...

European Geosciences Union

April 2014 – Oxygen isotopes and lakes by Prof Melanie Leng and Dr Jonathan Dean

Lakes occur across the globe and are sensitive to climatic change. Analysing the sediments that have accumulated at the bottom of lakes over time can help us to reconstruct past environmental change...

Lake Tibetanus in northern Sweden

March 2014 – Geoblog on the new mass spectrometer at the BGS

The British Geological Survey (BGS) took delivery of a new mass spectrometer this month. This instrument, acquired with joint funding from the University of Nottingham, will provide the UK’s environmental geoscience community access to one of the most precise research equipment for use in environmental research. Melanie Leng tells us more...

Prof Mel Leng with the new mass spectrometer

February 2014 – Ancient Climate Secrets by Jonathan Dean

Jonathan Dean started working as a Stable Isotope Apprentice in NIGL this January after he finished his PhD research at the University of Nottingham. Here he tells us a little bit about his research into how lake sediments are revealing secrets of past climates...

Standing on the rock on which the first peace treaty in human history was signed between the Hittites and the Egyptians

February 2014 – Have Volcanic Super-Eruptions Impacted on the Course of Human History? By Prof Melanie Leng

Today Melanie Leng, an isotope geochemist and palaeoclimatologist at the BGS, tells us about the Toba super volcano in Sumatra, Indonesia, which has erupted on many occasions over geological time...

The ancient Toba caldera (a basin left by the volcano after eruption) from space is now occupied by a huge lake (©NASA)

January 2014 – BGS GeoBlog – The Quaternary Research Associations 50th Anniversary Conference by Prof Melanie Leng

The new year traditionally brings with it not only resolutions, gym memberships and fad diets but for our scientists a round of exciting geological conferences...

The audience at the QRAs Quaternary Revolutions meeting (©Tim Lane)

Top of page

Grants & Awards

September 2014: ICDP funding success to drill Lake Challa on Mount Kilimanjaro to investigate megadroughts

Lake Challa

The DeepCHALLA project has secured nearly £0.5 million from the International Continental scientific Drilling Program (ICDP) towards drilling costs in order to conduct an unrivalled suite of state-of-the-art investigations into equatorial climate change using environmental proxies, chronological tools and climate modelling. The objectives are: to collect long cores from Lake Challa (encompassing an estimated 250,000 years); to establish a chronology for the new cores through a range of state of the art techniques; and to better understand climate and ecological change in equatorial East Africa using a variety of methods. A major target is to investigate the existence of so-called ‘megadroughts’; periods of millennial-scale aridity around 100,000 years ago. Such long and intensely dry events in the monsoonal African climate history are an unexpected phenomenon, and their precise timing, origin and extent, have yet to be established. The sensitivity of Lake Challa to climate variability, and the potential to develop an excellent uninterrupted chronology for its sediment record, makes it an ideal site to investigate these megadroughts.

The multi international team of researchers is overall led by Professor Dirk Verschuren (Ghent University, Belgium). The UK team comprise Prof Philip Barker (University of Lancaster), Prof Melanie Leng (BGS/University of Nottingham), Dr Christine Lane (University of Manchester), Dr Maarten Blaauw (Queens University Belfast), Prof Barbara Maher (University of Lancaster), Dr Rob Marchant (University of York) and Dr David Ryves (University of Loughborough).

February 2014: International Drilling Panel for Professor Melanie Leng

Dr Chris VaneMelanie Leng has been nominated to represent the International Continental scientific Drilling Program (ICDP) on the International Ocean Discovery Program (IODP)/European Consortium for Ocean Research Drilling (ECORD) outreach task force.

Working together, the ICDP and IODP have organised an outreach task force to facilitate joint outreach activities that might include conference booths/sessions and town hall meetings etc., which develops on from the combined 'Scientific Drilling' journal.

The task force will have a remit to develop new outreach tools and strategies for the long-term. Please contact Melanie if you are interested drilling outreach.
Follow ICDP on Twitter: @icdpDrilling and Mel: @MelJLeng

August 2013: Top spot for Quaternary Science Reviews article on isotopes in climate change research

Quaternary Science ReviewA review article on the use of isotope geochemistry in lake sediments as a means of understanding past climates remains one of the top down loaded articles in, the environmental change journal, Quaternary Science Reviews. The paper by Professor Melanie Leng (BGS/University of Leicester) and Professor Jim Marshall (University of Liverpool) has been consistently one of the journal’s most down loaded articles since its publication in 2004. As a reward for it’s popularity the journal have made the article open access till 31st October 2013. The paper has been cited over 350 times (Google Scholar).

The full article reference: Leng, M.J. and Marshall, J.D. 2004. Palaeoclimate interpretation of stable isotope data from lake sediment archives. Quaternary Science Reviews, 23, 811-831.

July 2013: NERC £1.2 m grant: Climatic change and human evolution

Lake sedimentThe Natural Environment Research Council (NERC) has approved a grant of £1.2 m to a UK team including researchers at the British Geological Survey (BGS) to investigate the influence of past climatic changes on human evolution in Africa.

In November 2013, working with partners from Germany, the US, and Ethiopia, the team will drill a 400 m-deep sediment core from Chew Bahir, an ancient lake basin in south Ethiopia, close to some of the world's most famous human fossil sites.

Over the next three years, the cores will yield a high-resolution record of changes in rainfall, temperature and vegetation spanning at least the last 500 000 years, a period that covers the evolution of our species, Homo sapiens, and dispersal of our distant ancestors from Africa into Asia and Europe.

Until now, there have been no such long environmental records from the African centre of human origins, so ideas about how climatic change may have influenced the emergence and dispersal of modern humans have remained largely speculative. By placing the fossil and archaeological data against a detailed record of regional climatic variation, and by modelling the likely effects of changing local environments on ancient human populations, the project will develop the first rigorous tests of hypotheses about how climate drove the genetic and cultural evolution of our species, and our eventual spread to every part of the globe.

The Chew Bahir project is part of the Hominin Sites and Paleolakes Drilling Project, a multi-national research effort to obtain core records of climatic change from five key palaeoanthropological sites in east Africa, covering the last four million years of human evolution.

The UK part of the project is headed by Professor Henry Lamb (Aberystwyth University) who leads a strong research team, including Professor Melanie Leng (BGS/University of Leicester) as well as scientists from Bangor, Liverpool, Newcastle, Oxford, and St Andrews universities.

The research is also supported by grants from the National Science Foundation (USA), the German Research Foundation (DFG), and the International Continental Scientific Drilling Programme.

Cores, from Kenya and Chew Bahir will be analysed initially at the US National Lake Core laboratories (LacCore) at the University of Minnesota, Minneapolis. Samples for dating, microfossil, and geochemical/isotope analysis will then be studied at the team's specialist laboratories (including the BGS stable isotope laboratory) in the UK and Cologne, Germany.

Top of page

Conferences and courses

The Nitrogen cycle and the Anthropocene

There are several types of temporal record (ice cores, sediments, tree rings) which show a reduction in 15N/14N ratios during the 'Anthropocene', a period in which there has been a substantial increase in the amount of reactive nitrogen in the earth’s nitrogen cycle. These changes are thought to be mainly due to the industrial synthesis and application of fertilizers, other changes in farming, and the combustion of fossil fuels. However, there does not seem to be any general agreement on the mechanism/s which cause this change in 15N/14N ratios, or indeed whether the changes in different records are related.

The workshop will therefore aim to promote discussion around: 15N depletion in organic matter in recent lake sediments; the lag between 15N in recent ice cores and lake sediments; recent 15N changes in modern plants/trees and soils; changing sources of N in glaciers and ice cores; and on how changes in source inputs to the atmosphere, and/or changes in its chemistry processes during the past few hundred years might have resulted

Nitrogen Cycle Workshop 2014.jpg

in a decrease in 15N/14N of deposited N? We have invited three guest speakers: Dr Tim Heaton (BGS), Professor Eric Wolff (Cambridge), and Dr Jan Kaiser(UEA), and welcome other suggestions.

Informal posters will also be encouraged as there will be time to discuss particular case studies.

The meeting will be a one day event, to be held at the British Geological Survey in Keyworth, provisionally booked for Wednesday 29th October 2014. Contact Prof Melanie Leng for more information or register an interest in attending.

Top of page