Sessions > PP3 Paleoenvironments & Paleoclimates
SYMPOSIUM PP3 - PALEO-ENVIRONMENTS AND PALEO-CLIMATES
Chairs. Guillaume DERA (University of Toulouse III - GET, FRA), Emmanuel CHAPRON (University of Toulouse II - GEODE, FRA), Pierre PELLENARD (University of Bourgogne, FRA), Michael JOACHIMSKI (GeoZentrum Nordbayern, Erlangen, DEU)
From Precambrian to modern times, climate and environmental changes have markedly paced the history of the Earth at different time scales. This includes shifts from greenhouse to icehouse modes, hyperthermal or snowball events, sea-level fluctuations, or disturbances in the carbon cycle and redox conditions, as well as abrupt climate changes during glacial or interglacial intervals and catastrophic events with large regional impacts. These changes are mirrored by profound modifications in the dynamics of marine and continental ecosystems documented in the sedimentary record.
The objectives of this symposium are to gather abstracts involving a broad scientific community to document and discuss the dynamic, timing and origin of environmental and climate changes at different time scales in order to better understand the driving forces of sedimentary processes on Earth. We encourage multidisciplinary studies for various geological periods combining sedimentary geology, stratigraphical methods, elemental, organic or isotope geochemistry, paleoecology, paleoceanography, as well as modelling. Abstracts devoted to new methodological perspectives in paleoenvironmental reconstructions (e.g., proxies for seawater temperature, pH, redox conditions, paleo-circulation, productivity, atmospheric pCO2) are welcome. Abstracts focusing on well-dated paleohydrological changes using flood records and glacier or lake level fluctuations are appreciated. This will be also an opportunity to discuss, exchange, and debate sedimentary records and processes specific to the Anthropocene and ongoing global warming.
Conveners. Guillaume DERA (University of Toulouse III - GET, FRA), Emmanuel CHAPRON (University of Toulouse II - GEODE, FRA), Pierre PELLENARD (University of Bourgogne, FRA), Michael JOACHIMSKI (GeoZentrum Nordbayern, Erlangen, DEU)
Description. This open session invites contributions on the general topics related to Paleo-Environments and Paleo-climates. It is an opportunity to present studies that do not fall within research covered by the special sessions PP3.1 to PP3.13.
Description. This session aims to bring together those working on aspects of paleoenvironmental change in the late Paleozoic (Carboniferous and Permian periods), including but not restricted to the late Paleozoic Ice Age and the end-Permian mass extinction. We seek a broad range of contributions that utilize sedimentology, stratigraphy, sedimentary geochemistry, paleoecology, or any combination of those disciplines, to advance understanding of the dynamic late Paleozoic world.
Conveners. Sylvie BOURQUIN (Géosciences Rennes, FRA), Arnaud BRAYARD (University of Bourgogne, FRA), Frédéric FLUTEAU (IPG Paris, FRA), Rossana MARTINI (University of Geneva, CHE), Alastair RUFFELL (Queen's University, Belfast, IRL)
Description. The end Permian was marked by the biggest known crisis of Earth's history and corresponds to major changes in oceans, continental surfaces and climate. The post-extinction biotic recovery dynamics during the Triassic is still under debate, both in continental and marine environments. These events are preserved in the sedimentological, geochemical and paleontological records of sedimentary basins, forming reliable archives retracing the history of the Earth in time and space.
This session aims to provide the broadest view of the global biological and ecological changes that occurred at the Paleozoic/Mesozoic boundary. Based on the stratigraphic record and integrated data obtained from sedimentary and biodiversity s.l. analyzes, geochemical tracers, as well as climate and biogeochemical modelling, the session will provide better paleoenvironmental reconstructions, constraining the climate evolution from the Permian to the Late Triassic.
Description. The Jurassic and Cretaceous periods were punctuated by several major climatic/environmental upheavals associated with biological crises (Triassic–Jurassic, T–OAE (Jenkyns Event), Weissert Event, OAE1a, OAE2), followed by recovery and radiations, but also by less well-known or minor climatic and paleoenvironmental changes, such as cold snap events in a broadly greenhouse climate, or minor carbon isotope excursions and anoxic events. The paleogeography associated with the progressive break-up of Pangaea, combined with volcanism and tectonism, played an important role in these events. Progress in stratigraphy (temporal framework, timing and correlation of events and durations) and the new methods used to decipher these environmental changes have modified our view of this fascinating period of time.
In this session, we invite contributions dealing with all these topics, stimulating interdisciplinary discussion (e.g. sedimentology, geochemistry, paleontology, stratigraphy), focusing on various sedimentary environments (whether continental or marine), and including new data, syntheses and models, leading to better understanding of the dynamic Jurassic-Cretaceous world.
Description. Tertiary is a key period of Earth climate history spanning between a warm greenhouse Late Paleocene epoch and a cold icehouse Quaternary period. This global cooling led to modern climate with bipolar glaciation associated to low atmospheric pCO2 and large latitudinal temperature gradients. During this period, plate tectonic, biosphere evolution, hydrosphere and atmosphere undergo major changes that are recorded in the sedimentary archives at different time-scales.
This session seeks contributions focussed on both long and short-term studies of climate and paleonvironmental changes. From multi-proxy analysis to climate modelling, of contributions are expected aiming at better understanding and constraining chronology, synchronism, dynamic and forcing parameters of the Tertiary climate history.
Conveners. Mario MORELLÓN (CITIMAC, Santander, ESP), Anaëlle SIMONNEAU (ISTO University of Orléans, FRA), Santiago GIRALT (CSIC-Institute of Earth Sciences Jaume Almera, ESP), Didier GALOP (University of Toulouse II - GEODE, FRA), Blas VALERO-GARCÉS (CSIC-Pyrenean Institute of Ecology, ESP)
Description. Both the Mediterranean basin and the adjacent areas of Southern Europe, such as the Pyrenees, have been subjected to significant climate fluctuations over the last millennia (from the Holocene to more recent times), and more particularly intense changes in the hydrological cycle. This region has also been densely populated since prehistoric times, experiencing different cultural trajectories which led, among others processes, to significant and different human-driven land managements through time. This area is therefore ideally suited to study both past long and short-term landscape transformations correlated with the complex interactions between climate variability and human activities. Lacustrine sediments have demonstrated to be one of the best continental continuous archives, in which high-resolution multi-proxy analysis and integrated approaches allow characterizing both climate, environmental and cultural changes in continental areas and their complex interplay.
This session aims to improve our understanding of these human-climate-environment interactions over Southern Europe by the compilation or the comparison of paleoclimatic, paleohydrological and paleoenvironmental records based on continental and coastal lake sediments and/or regional studies spanning the last millennia of the Earth’s history. We particularly expect multidisciplinary studies dealing with monitoring data describing actual processes or Holocene reconstructions giving a global view of past ecosystem trajectories and associated driving factors.
Conveners. Magali DELMAS (University of Perpignan-Via Domitia, FRA), Christine PERRIN (MNHN Sete, FRA), Emmanuel CHAPRON (University of Toulouse II - GEODE, FRA), Laurence VIDAL (CEREGE Aix-Marseille, FRA), Vincent JOMELLI (University of Paris, FRA)
Description. Recent progress in mapping and dating technics of landforms and sedimentary sequences or deposits in both subaquatic and terrestrial environments allow tracking climate changes during the Quaternary and particularly over the last glacial cycle. Mid latitudes are today exposed to key large scale climatic features involving oceanic and atmospheric circulations and we need to better understand how global warming may impact continental areas. Multi proxy paleo records and modeling approaches are thus needed to take into consideration climate variability over variable time scales, and to better imagine our future.
This session will focus on responses of glacial, lacustrine, fluvial, karstic and marine systems to climatic changes in mid-latitude mountains and surrounding areas. Mountains are specific environments in several ways. The relatively small size of catchments facilitates the monitoring of sediment flux from source to sink, and thus help to unravel the coupling effects between glacial, lacustrine, karstic and fluvial systems. Moreover, environmental responses to climatic changes may be enhanced by degradation of climatic conditions with altitude, even if topo-climatic effects can disturb global climatic signals.
Accordingly, this session aims to host contributions dealing with glacial, lacustrine, fluvial, karstic and/or marine records. A large spectrum of biotic, geochemical and physical proxies is welcome for inferring a variety of climatic parameters, such as air temperature, precipitation, soil (or air) moisture, extreme hydrometeorological events, seasonality. In order to highlight the specificities/complementarities of each kind of record in term of paleo environmental reconstruction, we wish to discuss:
Description. Glacial epochs are relatively rare in Earth’s history but have recurred episodically since at least 2.9 Ga and played an important role in shaping the evolution of life and the environment. For example, global (snowball) glaciations at the beginning and end of the Proterozoic appear to be linked to increases in atmospheric O2 and fundamental changes in the biosphere, whereas Paleozoic glaciations are associated with mass extinctions. The geological record of past ice ages has also been pivotal in reconstructing ancient paleogeographies and testing global climate models. Nevertheless, the geological evidence for ancient glaciations is commonly controversial and hypotheses for what triggered global cooling continue to be intensely debated.
The aim of this multidisciplinary session is to share and discuss new data bearing on the timing, causes, impacts, and sedimentary records of ancient glaciations—from the Archean to the Cenozoic. We seek submissions from diverse perspectives, including (but not limited to) the sedimentary and sequence stratigraphic imprint of glaciation, new chronometric constraints on the timing, timescale, and tempo of past glaciations, geochemical and fossil evidence informing the trigger mechanisms for global cooling, and modeling studies aimed at understanding glacial and deglacial processes. We further encourage submissions presenting novel approaches to reconstructing the extent and drivers for ancient glaciation.
Conveners. Chloé MORALES (University of Utrecht, NLD), Karl FÖLLMI (University of Lausanne, CHE), Jörn PECKMANN (University of Hamburg, DEU), Gregory PRICE (Plymouth University, GBR), Nicolas TRIBOVILLARD (University of Lille 1, FRA)
Description. The formation of authigenic minerals (carbonates, phosphates, iron oxides, salts, etc.) results from microbially induced or abiotic processes that take place at or below the sediment-water interface. They can provide crucial insights on ambient environmental conditions and in-situ (bio)geochemical processes at the Earth surface and in deeper sedimentary layers.
In this session, we invite contributions focusing on various aspects of authigenesis, which range from the processes of mineral formation (biotic and abiotic), the disentangling of the effects of early and late diagenesis, their relationship with paleoceanographic and paleoclimate settings and/or their potential for paleoenvironmental reconstructions
Conveners. Yannick DONNADIEU (CEREGE Aix-Marseille, FRA), Yves GODDÉRIS (CNRS - GET, FRA), Paul VALDES (University of Bristol, GBR), Ros RICKABY (University of Oxford, GBR), Emmanuelle PUCÉAT (University of Bourgogne, FRA)
Description. Recent years have seen major advances in many geochemical techniques and an increase in the complexity of Earth System Models. The aim of this session is to share progress in our understanding of global climate changes occurring during the pre-Quaternary based on the integration of geochemical/ paleobotanical/ sedimentary techniques and numerical models. The geological record provides insight into how climate processes and the carbon cycle may operate and evolve in a high CO2 environment and the nature of the climate system during a turnover from glacial to greenhouse state — a transition that may potentially occur in the near future.
We seek abstracts that reconstruct Earth’s climate and the carbon cycle, investigate how the interconnections of the key surface reservoirs impact climate (vegetation-ocean-atmosphere), identify climatic tipping points and thresholds, and explore the climate response to extraordinary events. Pertinent themes may include past episodes of glaciation and deglaciation, greenhouse-icehouse transitions and intervals of high atmospheric CO2, and rapid or abrupt climate transitions.
Description. An understanding of the controls of past carbonate sedimentation is fundamental to predicting the future of carbonate deposition. The atmospheric CO2 concentration is approaching levels comparable to those last experienced 40–50 million years ago. The records of climatic, oceanographic and environmental changes preserved in carbonate sequences can provide new insights into the likely consequences of human activities.
In this session we shall explore a range of geochemical, biological and stratigraphic proxies and their applications to understand the sedimentary record of carbonate successions in the Earth history context.
Description. The distribution and density of carbonate-producing benthic organisms highly depends on environmental variables, such as light, temperature, nutrients, current speed, substrate texture and supply rates. In turn, growth and development of benthic communities, as well as post-mortem processes affecting their remains, may highly influence the seafloor morphology, sediment properties and other aspects of the seabed. This is true especially of marine ecosystem engineers, either producing carbonates (such as corals, coralline algae, bivalves) or lacking mineralized skeletons (e.g. seagrass, cyanobacteria, burrowing macrofauna). There are also important organism-organism interactions at work, such as in the case of bioerosion.
The mechanisms fostering or inhibiting these interactions within carbonate depositional systems are still little understood. But clearly the modifications wrought on the physical surrounds by the benthic biota influence the acoustic signals used to map the seafloor, which implies that acoustic remote sensing potentially conveys information on presences, types and changeability of benthic communities and their carbonate production. Different acoustic systems can cover various resolutions and footprint sizes.
This session aims at bringing together scientists interested in modern and ancient marine bio-geo interactions, with special emphasis on carbonate depositional settings from shallow- to deep-water environments. Our main goal is to promote a constructive cross-disciplinary debate on:
Description. Biogenic structures produced by living organisms have proven to be exceptionally valuable for paleoenvironmental reconstructions and stratigraphic analyses. Most studies of trace fossils focus on the marine realm, whereas scant attention has been on trace fossils in the continental domain.
This session is interested in the description, classification, interpretation, and/or application of trace fossils preserved in continental or marginal marine settings (e.g., lacustrine, fluvial, eolian, soils, deltaic, estuarine). All studies including trace fossils in the geological record, modern environments, lab experiments, or imaging techniques are most welcome.
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