A5040877678- Methane Hydrates and Related Phenomena
- Geology and Paleoclimatology Research
- Astro and Planetary Science
- Isotope Analysis in Ecology
- Astronomical Observations and Instrumentation
- Paleontology and Stratigraphy of Fossils
- Hydrocarbon exploration and reservoir analysis
- Geological and Geophysical Studies
- Planetary Science and Exploration
- Geological formations and processes
- Seismic Imaging and Inversion Techniques
- Offshore Engineering and Technologies
- Spacecraft and Cryogenic Technologies
- Reservoir Engineering and Simulation Methods
- Geophysics and Gravity Measurements
- Geological Studies and Exploration
- Marine and environmental studies
- Astronomy and Astrophysical Research
- Scientific Research and Discoveries
- Geological and Geochemical Analysis
- Marine Biology and Ecology Research
- Solar and Space Plasma Dynamics
- Cryospheric studies and observations
- Geomagnetism and Paleomagnetism Studies
- earthquake and tectonic studies
University of Exeter
2017-2025
British Geological Survey
2015-2024
Woods Hole Oceanographic Institution
2020
University of Nottingham
2014-2017
International Ocean Discovery Program
2015
University of Leicester
2014
University College London
2005-2009
UCL Australia
2005
Abstract The Paleocene–Eocene Thermal Maximum (PETM) was a period of geologically-rapid carbon release and global warming ~56 million years ago. Although modelling, outcrop proxy records suggest volcanic occurred, it has not yet been possible to identify the PETM trigger, or if multiple reservoirs were involved. Here we report elevated levels mercury relative organic carbon—a for volcanism—directly preceding within early from two North Sea sedimentary cores, signifying pulsed volcanism...
Environmental changes associated with the Paleocene–Eocene thermal maximum (PETM, ∼56 Ma) have not yet been documented in detail from North Sea Basin. Located within proximity to Atlantic igneous province (NAIP), Kilda Basin, and northern rain belt (paleolatitude 54 °N) during PETM, this is a critical region for testing proposed triggers of atmospheric carbon release that may caused global negative isotope excursion (CIE) marine terrestrial environments. The CIE onset identified organic...
The Early Jurassic Epoch was a predominantly greenhouse phase of Earth history, but comprehensive understanding its climate dynamics is hampered by lack high resolution multi-proxy environmental records. Here we report geologically brief (approximately several hundred thousand years) negative carbon isotope excursion (CIE) 2–3‰ in both marine and terrestrial materials, recognised for the first time Late Sinemurian Substage (Early Jurassic, ~ 194 Ma) eastern England. excursion, which termed...
Significance The cause of the rise in atmospheric pCO 2 over last deglaciation has been a puzzle since its discovery early 1980s. It is widely believed to be related changes carbon storage deep ocean, but exact mechanisms responsible for releasing CO from deep-ocean reservoir, including role ocean density stratification, remains an open question. Here we reconstruct intermediate-deep gradient South Atlantic across and find evidence deglacial chemical destratification late These results...
The Mid-Pleistocene Transition (MPT) is characterised by cooling and lengthening glacial cycles from 600-1200 ka, thought to be driven reductions in CO2 particular ~900 ka onwards. Reduced high latitude upwelling, a process that retains within the deep ocean over glacials, could have aided drawdown but has so far not been constrained either hemisphere MPT. Here, we find reduced nutrient upwelling Bering Sea, North Pacific Intermediate Water expansion, coincided with MPT became more...
Abstract Understanding the composition of clay-rich sediments and their transportation into proximal marine basins allows us to better decipher hydroclimatic changes before within Palaeocene–Eocene Thermal Maximum (PETM). Only a limited number such studies exists from North Sea Basin, which was volcanic activity early rifting hypothesized have triggered PETM. The present study examines core material well 22/10a-4, UK Sea, as it exhibits an exceptionally expanded almost stratigraphically...
Over the last 5 million years, global climate system has evolved toward a colder mean state, marked by large-amplitude oscillations in continental ice volume. Equatorward expansion of polar waters and strengthening temperature gradients have been detected. However, response mid latitudes high Southern Hemisphere is not well documented, despite potential importance for feedbacks including sea distribution low-high latitude heat transport. Here we reconstruct Pliocene-Pleistocene history both...
Sea ice and associated feedback mechanisms play an important role for both long- short-term climate change. Our ability to predict future sea extent, however, hinges on a greater understanding of past dynamics. Here we investigate changes in the eastern Bering prior to, across, after Mid-Pleistocene transition (MPT). The record, based Arctic biomarker IP25 related open water proxies from International Ocean Discovery Program Site U1343, shows substantial increase extent across MPT....
Late Miocene climate evolution provides an opportunity to assess Earth's sensitivity carbon cycle perturbation under warmer-than-modern conditions. Despite its relevance for understanding the system, driving mechanisms underlying profound and changes – including enigmatic cooling from 7 5.4 million years ago remain unclear. Here, we present magnetic geochemical paleoceanographic proxies a hydrogenetic ferromanganese crust retrieved in northwestern Pacific Ocean. Our results indicate striking...
Abstract The Eocene–Oligocene Transition (EOT: ∼34.4–33.7 Ma) marks a major climatic shift from warmhouse to coolhouse state, characterized by the extinction of rosette‐shaped calcareous nannofossils ( Discoaster spp.) and expansion first large‐scale Antarctic ice sheet. While changes in ocean circulation declining atmospheric CO 2 levels have been proposed as primary drivers, recent studies emphasize role carbon cycle. This study investigates paleoceanographic Western Pacific using...
High latitude deep water upwelling has the potential to control global climate over glacial timescales through biological pump and ocean-atmosphere CO2 exchange. However, there is currently a lack of continuous long nutrient records with which assess this mechanism. Here we present geochemical proxy for North Pacific Intermediate Water (GNPIW) formation in Bering Sea past 850 kyr, demonstrates that periods were characterised by reduced upwelling, when atmospheric temperature also lowered. We...
Analysis of a 630m section an exploration well penetrating the distal part Congo Fan (~2000m water depth) yielded high abundance and diversity assemblages agglutinated calcareous benthic foraminifera. Planktonic foraminifera constrain age to Early – Middle Miocene, 18O records reveal Mi1 (~16.3 Ma) isotopic shift. Relatively few taxonomic studies deep-water exist from this time period in locality. All species encountered are therefore taxonomically described documented using SEM photography...
Reconstruction of intermediate water properties is important for understanding feedbacks within the ocean-climate system, particularly since these masses are capable driving high–low latitude teleconnections. Nevertheless, information about mass evolution through late Pleistocene remains limited. This paper examines changes in Antarctic Intermediate Water (AAIW), most extensive modern ocean last 400 kyr using stable isotopic composition (δ18O and δ13C) trace element concentration (Mg/Ca...
Bering Sea sediments represent exceptional archives, offering the potential to study past climates and biogeochemistry at a high resolution. However, abundant hydrocarbons of microbial origin, especially along eastern continental margin, can hinder applicability palaeoceanographic proxies based on calcareous foraminifera, due formation authigenic carbonates. Nonetheless, carbonates may also bear unique opportunities reconstruct changes in sedimentary redox environment. Here we use suite...
Abstract The Antarctic Cold Reversal (ACR; 14.7 to 13 thousand years ago; ka) phase of the last deglaciation saw a pause in rise atmospheric CO 2 and temperature, that contrasted with warming North. A reexpansion sea ice northward shift position westerly winds Southern Ocean are well‐documented, but response deep‐sea biota primary drivers habitat viability remain unclear. Here, we present new perspective on ecological changes deglacial Ocean, including multifaunal benthic assemblage...
Abstract The Paleocene–Eocene Thermal Maximum (PETM) was a global hyperthermal event ∼56 Ma characterized by massive input of carbon into the ocean–atmosphere system and warming. A leading hypothesis for its trigger is emplacement North Atlantic Igneous Province (NAIP), with extensive extrusion/intrusion igneous material nearby sedimentary basins, forcing local uplift warming‐inducing emissions. It remains unclear if oceanographic changes in Sea–Norwegian Sea–Arctic such as anoxia...
Large Igneous Provinces (LIPs) are associated with global warming and carbon cycle perturbations during Oceanic Anoxic Event 2 (OAE2, ~94 Ma) the Mid-Cenomanian (MCE, ~96.5 Ma). However, there is still no consensus on role volcanism played as a trigger, or its source - previously ascribed to Caribbean LIP High Arctic LIP. Here, we use Mentelle Basin sedimentary mercury (Hg) concentrations determine timing of volcanism, neodymium (Nd) strontium (Sr) isotopes for provenance. Hg compared...