Special Session on Astrogeology, Impact Craters and Meteorites
Special Session on Astrogeology, Impact Craters and Meteorites
28 November 2022
16:30—18:30 Morocco Local Time (UTC+1)
This special session is dedicated to oral/poster presentations on new discoveries and research advances focusing on Astrogeology, Impact Craters and Meteorites from the following disciplines: Astronomy, Geology, Physics (Geophysics, Astrophysics), and Chemistry (Geochemistry and Cosmochemistry). The multi-disciplinary approach involving Astrophysicists and Geologists is fundamental to better understand and know more about the evolution of planets and asteroids.
Impact cratering is a fundamental science on understanding and following the evolution of planets including the Earth’s history. African and Arabian countries have a low number of officially recognized impact structures and significant discoveries are expected. In view of the large extension of deserts and old surfaces in these regions, further explorations of new impact craters should be conducted.
It is therefore the aim of this session to know more and learn about the impact structures that remained under-explored. Moreover, the session will discuss newest studies on meteorites and will showcase new discoveries in Meteoritics. In particular, it will focus on the contribution of Meteorites collected in Africa and the Arab countries to Meteoritics and Planetary science development.
Hasnaa Chennaoui Aoudjehane
Meteoritical Society Fellow
Laureate, “Prix Paul Doistau–Émile Blutet” from the French Academy of Sciences
Editor of Arabian Journal of Geosciences (Springer)
Professor, Hassan II University of Casablanca, Morocco
Senior Research Associate
Fonds de la Recherche Scientifique (FNRS)
Professor at the Université libre de Bruxelles (ULB)
Philippe F. Claeys
Vrije Universiteit Brussel
Philippe Claeys is a geologist, planetary scientist, and geochemist interested in documenting ancient and modern global changes and in particular the consequences of asteroid and comet impacts on the evolution of the bio-geosphere. He obtained his Ph.D. in 1993 at the University of California (UC) at Davis working on the discovery of the Chicxulub crater in Yucatan, the most likely cause of the mass extinction that wiped out the dinosaurs, 66 million years ago, with Walter Alvarez(UC Berkeley) as an advisor. He then carried out postdoctoral research using Neutron Activation to analyze Platinum group elements in sediments at the Institute of Geophysics and Planetary Physics at UCLA, in the group of John Wasson. For several years, he was a researcher at UC Berkeley working again with Walter Alvarez on the KT boundary mass extinction. In the late nineties, Dieter Stoeffler convinced him to join the Museum of Natural History in Berlin as chief scientist in charge of establishing and managing the new analytical laboratories, composed of scanning & transmission electron microscopes, an electron microprobe, and several X-ray fluorescence instruments. In 1998, was a visiting professor at the “Ecole des Mines” in Paris. Since 2001, he is a professor at the “Vrije Universiteit Brussel” in Brussels, Belgium, where he established and directs the research unit “Analytical-Environmental and Geochemistry” (AMGC), which is composed of a multidisciplinary team of ~ 85 researchers, geologists, chemists, biologists, civil-& bio-engineers, as well as archaeologists. AMGC relies on a vast arsenal of analytical techniques such as Mass Spectrometry for trace elements and isotope determinations, Micro-X-Ray Fluorescence, Fourier Transform Infra-Red spectroscopy etc. He is also a visiting professor at Ghent University, the Catholic University Leuven (till 2021) and the University of Liège. In 2016-2017, he was invited as International Scholar by the Peter Wall Institute for Advanced Studies at the University of British Columbia. Philippe also actively spreads science results to a large public audience via conferences, school visits, social media, vulgarization papers, active communication towards the written press, TV, radio, and internet (see Youtube), and participation in documentaries. When he is not traveling looking for clues to better understand the 4.5 billion years of evolution of planet Earth, he enjoys designing, writing, and obtaining new projects as well as guiding Ph.D. students and postdocs on a wide variety of topics ranging from Antarctic meteorites and impact crater formation to global environmental changes and cyclostratigraphy or bioarchaeology.
K-Pg Ir Positive Anomaly from Distal Ejecta to Chicxulub Peak-ring: Closing the Loop
A positive Ir anomaly (ppb) at the K-Pg boundary in Gubbio (Italy) supports the theory that, 66 million years ago, a ~10 km meteorite collided with Earth, inducing a major mass extinction. This platinum group element (PGE) enrichment is now identified at > 100 continental and marine K-Pg boundaries worldwide and unique within the late Maastrichtian and Lower Paleocene stratigraphy; it is also accompanied by low radiogenic Os value. PGE elemental distribution, together with Os & Cr isotope ratios constrain the nature of the impacting meteorite to a specific carbonaceous chondritic (CM or CR). These mm to cm-thick units represent the distal ejecta spread all over the world by the formation of the Chicxulub crater, in Yucatán. Closer to the impact site, Ir occurs at the very top of more expanded proximal K-Pg sequences. At the rim of the Gulf of Mexico, tsunami, and large debris flows induced a higher influx of sediments that diluted and vertically spread the PGE anomaly.
In 2016, the IODP-ICDP Exp. 364 recovered a ~830 m near-continuous core within the Chicxulub peak-ring containing a ~75 cm thick succession of post-impact sediments deposited on top of a ~130 m thick impact melt rock and suevite sequence, just below the appearance of the first Paleocene pelagic carbonates. This ‘transitional unit’, is composed of generally fining-upward, laminated dark brown to dark grayish brown carbonate-rich silty claystone to micrite. A clear positive Ir anomaly of more than 1 ppb is measured towards its very top, comparable in magnitude and pattern to other proximal K-Pg boundaries. Clearly, the ultrafine Ir-rich dust transported across the entire planet in the aftermath of the impact event also settled within the newly formed crater, placing strict and unprecedented time constraints (<20 years) on the deposition of the transitional unit, and its underlying proximal impactite sequence. The identification of the now world-famous Ir anomaly on top of the Chicxulub impactite sequence conclusively ties the impact event to the global Ir layer identified at K-Pg boundary sections worldwide and unequivocally connects the Chicxulub crater to sediments recording the mass extinction of non-avian dinosaurs.
Special Session on climate and sea-level change during the Cenomanian-Turonian Anoxic Event: Synthesis of sedimentological, micropaleontological and geochemical records
29 November 2022
11:00—12:30 Morocco Local Time (= UTC+1)
During the Cretaceous, organic-rich black shales (with>5% total organic carbon (TOC) were deposited globally in various palaeogeographic settings.These black shales reflect episodes of anomalous environmental conditions, which have been called ‘‘oceanic anoxic events’’ (OAEs). Two major Cretaceous OAEs occured in the early Aptian (OAE 1a) and at the Cenomanian/Turonian transition (OAE 2), also known as the ‘‘C/T boundary event’’. The C/T boundary event coincided with peak « Greenhouse» climate conditions, associated with a period of enhanced oceanic crust production and volcanism, whichled to a major eustatic sea level rise. Marine biogenic carbonate and organic matter across the C/T boundary event are characterized by a positive excursion in stable carbon isotope ratios, reflecting the massive burial of organic carbon. This fundamental perturbation of the global carbon cycle had major ecological and environmental repercussions with implications for future climate projections.
This special session is dedicated to oral/poster presentations on new discoveries and research advances focusing on climate and sea-level change during the Cenomanian-Turonian Anoxic Event based on the synthesis of sedimentological, micropaleontological and geochemical records.
University of Kiel
El Hassane Chellai
University of Kiel
R. Mark Leckie
University of Massachusetts, Amherst MA, USA
Mark Leckie earned his Ph.D. in geology at the University of Colorado. He has been a Professor at the University of Massachusetts Amherst since 1985. He is a specialist in Cretaceous and Cenozoic planktic and benthic foraminifera. Mark has been very active with scientific ocean drilling since 1981. He has sailed as a shipboard scientist on 7 DSDP/ODP/IODP scientific expeditions, most recently IODP Exp 374 to the Ross Sea, Antarctica. He served as Co-Chief Scientist of ODP Leg 165. His deep-sea research has included a wide range of projects including Cretaceous Oceanic Anoxic Events (OAEs), Cretaceous and Cenozoic biostratigraphy and paleoceanography, Miocene sea level reconstruction, and Neogene glacial history of the Ross Sea. In addition to sea-going research, he has conducted field work on Upper Cretaceous rocks of the U.S. Western Interior for forty years, with much of his research focused on the Cenomanian-Turonian interval and OAE2. He has served as an associate editor for the journals Geology, Paleoceanography, and the Journal of Foraminiferal Research. Mark is a member of the international working groups for Cretaceous, Oligocene, and Neogene planktic foraminifera, and deep-sea benthic foraminifera. He co-led the initial JOI/IODP School of Rock (SoR) expedition in 2005, and has participated in multiple shore-based and shipboard SoR teaching workshops since. He has taught at the Urbino Summer School for Paleoclimatology. Mark is a co-author of Reconstructing Earth’s Climate History, Inquiry-Based Exercises for Lab and Class (St. John et al., 2021, 2nd ed.; Wiley-Blackwell). Mark is a UMass Amherst Distinguished Teacher. He teaches courses in Oceanography, History of the Earth, Geological Field Methods, Micropaleontology, and Paleoceanography.
In his keynote (planned at the Special Sessions) Mark Leckie will review the planktic and benthic foraminiferal record across the U.S. Western Interior, with a focus on how these microfossils inform us about the paleoceanography of the Western Interior Seaway (WIS) during Oceanic Anoxic Event 2 (OAE2). He will present data from sections spanning the seaway; from Texas and New Mexico in the south to Montana in the north, Utah and Arizona in the west and Kansas in the east. The Turonian GSSP is near Pueblo Colorao in the central axis of the seaway. This well-studied section is a key reference section that anchors the unique WIS OAE2 record. Correlation across the seaway is afforded by widespread volcanic ashfall deposits (bentonite beds) that are well dated radiometrically and reliably corrlated by a well-established molluscan biostratigraphy. Cyclical deposition during late Cenomanian transgression created alternating limestone-marl couplets that have been orbitally tuned. In additon to this astrochronology, ≏13Corg profiles provide another reliable means of correlation between sections.
Special Session on hydrogeological and climatic risks, their management and the effect of climate change on groundwater quality
28 November 2022
11:00—12:30 Morocco Local Time (= UTC+1)
This special session aims to consider innovative research from the perspective of hydrogeological and climatic risk, with a possible focus on its management and mitigation. In addition, it is also proposed to explore a topic that has been receiving much appreciation in the international scientific literature recently, the effects of climate change on groundwater quality. Risk analysis is increasingly fundamental for rational land management, especially in ongoing climate change. Critical issues such as floods, hurricanes or droughts are becoming systemic problems in many countries, although they are more acute in developing countries. At the same time, the water resource is becoming more and more precious precisely because it has been observed to be undergoing continuous degradation. As a result, there are increasingly strong indications of its dependence on climate change. This special session aims to stimulate a climate, hydrogeological and geological-geomorphological analysis using information technologies (satellite survey, GIS, etc.) that can, on the one hand, make decision-makers aware and, on the other hand, through careful management, support their choices.
Professor, Sapienza University of Rome, Rome, Italy
Research fellow, University of Camerino, Camerino, Italy
Professor, University of Camerino, Camerino, Italy
University of Trento, Italy
Dino Zardi is full professor of Atmospheric Physics at the University of Trento (Italy), where he works since 1995. He got a degree in Physics cum laude from the University of Bologna (1991) and a PhD in Hydrodynamics from the University of Genova (1995).
He is author or co-author of 86 articles published on international peer-reviewed scientific journals.
His research interests focus on boundary layer processes over mountainous terrain and their implications on air quality, agriculture, renewable energy resources, and climate change impacts.
He is also Director of the MSc programme in Environmental Meteorology, President of the Italian Association of Atmospheric Sciences and Meteorology (AISAM) and Co-Chief Editor of the Wiley and Royal Meteorological Society journal Meteorological Applications.
"Orographic effects in the atmospheric processes of the Mediterranean area"
Weather and climate characteristics of the regions surrounding the Mediterranean are strongly affected by marine effects associated with sea-atmosphere exchanges. However these areas are also characterised by a series of major mountain ranges, such as the Pyrenees, the Alps, the Apennines, the Dinaric Alps, the Pindhos, the Taurus, the Atlas, and many others. The combination of marine and orographic effects is conducive to a series of phenomena, either dynamically or thermally driven, which are reviewed in the talk. Climatic changes in the frequency of occurrence and in the intensity of the above phenomena, either observed or projected, are reviewed and discussed.