4-4-4-4-4-4-4-4-4-4-4-4-4 From: Sophie Butcher - BGS <sbutcher@xxxxxxxxx> Dear Colleagues, COMET (The Centre for Observation and Modelling of Earthquakes, Volcanoes, and Tectonics) invites you to the next installment of our COMET+ webinar series, viewable from the home office. *Variable Thermal and Magmatic Modification of the East African Lithosphere**Wednesday 4th December 2024 at 4pm UK time* (4pm UTC/ 5pm CEST/ 8am PDT) *Dr Rita Kounoudis* *University of Oxford, UK* *Please register at: * https://universityofleeds.zoom.us/webinar/register/WN_Ax8_UmCVQn2VDyaKgL-83A <https://urldefense.com/v3/__https://universityofleeds.zoom.us/webinar/register/WN_Ax8_UmCVQn2VDyaKgL-83A__;!!IKRxdwAv5BmarQ!ZtDtpijdZTUVGg0qCaXuO68jiYKejrTLBu8swbcWBNJFYrEw67FQYB33u2TXldlBpnFcZt-OgwA3I8AGpa9rDHaXlQ$> (After registering, you will receive a confirmation email containing information on how to join the webinar) *Abstract:* Continental flood basalt provinces mark Earthâ??s most voluminous magmatic events. Often associated with mantle plumes, their development is expected to alter the thermo-mechanical structure of the lithospheric mantle significantly. However, since post-large igneous province (LIP) cooling re-defines the base of tectonic plates, the extent of this modification, including its development through time, can only be assessed via theoretical models or from the geological record preserved at ancient LIPs. Here, we present new models of crustal and mantle seismic structure below the Turkana Depression of northern Kenya/southern Ethiopia where, despite presently sitting atop African superplume mantle, the lithosphere remains surprisingly un-perturbed by plume-related heating and magmatism. Evidence for lower crustal intrusionsâ??ubiquitous below the flood-basalt-capped Ethiopian Plateau to the northâ??is comparatively lacking below the Depression. The mantle lithosphere has also retained its cool, fast wave-speed â??lidâ?? character, in stark contrast to the heavily modified Plateau. The contrasting seismic and thermal structure of these neighbouring terranes may in part owe its existence to the African plate's slow northward motion during the Cenozoic. It is the Ethiopian Plateau that lay atop the initial, hottest pulse of plume material that impinged on the lithosphere during Eocene-Oligocene times. As well as plume-exposure, the Depressionâ??s unique extensional history is also likely to play an important role in plate modification. While pre-thinned lithosphere can, in some cases, enhance magmatism following plume arrival, the Turkana Depressionâ??s earlier (Mesozoic) episode of failed rifting appears to have instead suppressed its potential for further thermo-mechanical modification by rendering the lithosphere dry and refractory. The COMET+ webinar series promotes research by collaborators of COMET scientists. We aim to provide a platform for these researchers to showcase their work to large and international audiences, opening doors to broader collaborative networks and enhancing the communityâ??s diversity of backgrounds and ideas. Catch up on past COMET and COMET+ webinars on our YouTube page: https:/www.youtube.com/channel/UCtFDytX1hgjvlS4NH48M2oQ/video <https://urldefense.com/v3/__https://www.youtube.com/channel/UCtFDytX1hgjvlS4NH48M2oQ/videos__;!!IKRxdwAv5BmarQ!ZtDtpijdZTUVGg0qCaXuO68jiYKejrTLBu8swbcWBNJFYrEw67FQYB33u2TXldlBpnFcZt-OgwA3I8AGpa8xunPwTw$> Best wishes, Sophie Butcher, Edna Dualeh & Milan Lazecky COMET - Centre for the Observation and Modelling of Earthquakes, Volcanoes and Tectonics https://comet.nerc.ac.uk/ <https://urldefense.com/v3/__https://comet.nerc.ac.uk/__;!!IKRxdwAv5BmarQ!ZtDtpijdZTUVGg0qCaXuO68jiYKejrTLBu8swbcWBNJFYrEw67FQYB33u2TXldlBpnFcZt-OgwA3I8AGpa960z3hHg$> @NERC_COMET <https://urldefense.com/v3/__https://twitter.com/nerc_comet?lang=en__;!!IKRxdwAv5BmarQ!ZtDtpijdZTUVGg0qCaXuO68jiYKejrTLBu8swbcWBNJFYrEw67FQYB33u2TXldlBpnFcZt-OgwA3I8AGpa9NGCRJig$> 4-4-4-4-4-4-4-4-4-4-4-4-4 ------------------------------
