1-1-1-1-1-1-1-1-1-1-1-1-1-1 From: Britta Jensen <bjjensen@xxxxxxxxxxx> Dear All The submission deadline for the IAVCEI 2023 Scientific Assembly is fast approaching on the 2nd of September. Please consider submitting an abstract to one of the two Commission on Tephrochronology (COT) supported sessions: *1. Tephrochronology: new methods and applications for chronostratigraphy and beyond* Convenors: Dr Jenni L Hopkins, Professor David J Lowe, Dr Britta JL Jensen Traditionally, tephrochronology is the study and use of all explosively-erupted fall deposits as isochronous marker beds primarily to link and synchronise geological and archaeological sequences or deposits. However, in recent years tephra research has become increasingly important in a wider range of geological disciplines. Advances in technologies have allowed explorative boundaries to be extended, not only increasing potential to identify tephra from proximal to ultra-distal sites (e.g. cryptotephra deposits), but also to analyse the components using a range of new methodologies (e.g. micron-scale, single shard laser ablation techniques for measuring trace elements). The results of these studies are underpinning regional to global correlations between paleoenvironmental and archaeological records. Further to these developments, tephrochronology is being used increasingly in social science applications, providing quantitative inputs for ashfall modelling, and hazard and risk assessment and mitigation, and medical research. For this session, we invite papers from across all applicable studies involving tephrochronology. These may include scientific advances in methodologies (including cryptotephra research), and the growing use of tephrochronology across multiple disciplines, ranging from traditional applications (including paleoenvironmental and paleoclimatic reconstructions; archaeology) through to more novel approaches. *2. Constraining the tempo and magnitude of past highly explosive volcanism using tephrochronology: implications for volcanic hazard assessments* Convenors: Dr Paul Albert, Dr Steffen Eisele, Dr Karen Fontijn, Dr Francesca Forni, Dr Julie Schindlbeck-Belo Hazard assessments at many volcanoes are often hampered by incomplete or poorly preserved near-source eruption records due to their burial or destruction by younger explosive activity, erosion and weathering. While evidence of large magnitude eruptions can be lost from the geological record, mid- to low-intensity explosive eruptions are most susceptible to under-recording. Gaps in the near-source volcanic record make it difficult to accurately reconstruct the eruption history of a volcano, and in particular to reliably evaluate frequency-magnitude relationships over extended timescales. Distal to volcanic source, tephra layers preserved in long-continuous sedimentary archives (lacustrine, marine and peat), and even the polar ice cores, all used for palaeoclimate research, provide comprehensive records of explosive volcanism, particularly when fully integrated with proximal-medial eruptive successions. While these tephra layers are routinely utilised as chronological tools to aid palaeoclimate reconstructions, many of these archives are independently well-dated (e.g., 14C, annual layer counting) providing high-precision chronological constraints on the timing and frequency of activity at individual volcanoes. Constraints on the magnitude of past eruptions can be established by mapping the distribution and thickness of tephra deposits across suites of sedimentary records and developing regional tephrostratigraphic frameworks. Thus analysing tephra in these archives can provide crucial constraints on the scale, tempo and ash dispersals of past explosive volcanism, including useful insights into areas repeatedly impacted by ash fall and pyroclastic flows. These tephra repositories also provide key insights into the long-term chemical evolution of volcanic centres, and how this relates to the scale and timing of explosive volcanism. In this session, we welcome contributions that focus on using the tephrochronology of terrestrial, marine and ice core archives to construct more reliable eruption histories, to better understand eruption processes and past ash dispersals and those that use this information to aid more accurate volcanic ash fall hazard assessments. Full details on submission are available here on the conference website: https://urldefense.com/v3/__https://confer.eventsair.com/iavcei2023/__;!!IKRxdwAv5BmarQ!aLbHjrRr2Y2E9O8mJ4a6mEXoUC5vQe45XAfxVjhh51el5tBPQICWVKAC5_wn-eONxdO82qHDNfSz87wE$ <https://urldefense.com/v3/__https://confer.eventsair.com/iavcei2023/__;!!IKRxdwAv5BmarQ!dfW4uRXQwnsRYiWTkDjH6kAragKTXWiAs7OEaE_aAfxrWV3QbSePxXz4GvDgzgkENKZ3xB9f55_QABij5lY$> Best Wishes, COT executive 1-1-1-1-1-1-1-1-1-1-1-1-1-1 ------------------------------
