Accurately dating the geologic time is key to understanding the processes in Earth history, and especially critical to paleoclimatic and paleoenvironmental reconstructions and modeling. For instance, assisted by astronomically dated stable isotope records - some established by MARUM authors - significant progresses on the states and changes of the Cenozoic climate have been primarily achieved, revealing detailed timing of polar ice sheet growth and emphasizing its essential role. My own research involves integrating cyclostratigraphy and magnetostratigraphy to calibrate the geologic time scales of past periods, during which significant global climate disruptions have been globally archived. Astronomical tuning of sections, where a reliable magnetostratigraphy has been obtained, could provide highly precise numerical ages for magnetic reversal boundaries. As two enlightening examples, I will present some findings on the Late Triassic (Carnian Pluvial Episode) and early Cretaceous (Oceanic Anoxic Event, OAE1a of basal Aptian). Cycle-scaled magnetostratigraphy may also solve the notorious dating problems of Arctic Ocean paleoceanography that have been very much hindering us from fully elaborating the role of Arctic in Cenozoic cooling (“Arctic amplification”). The ArcOP IODP expedition in 2022 presents a great personal opportunity to test this approach on the “to-be-unprecedented” core materials.

Geoscientific Colloquium "Perspectives of non-seismic applied near-surface geophysics"

Online via Zoom:
https://uni-bremen.zoom.us/j/96524048625?pwd=VXAyWEVqNHo2Mzd3N1IrSVVrSVNIZz09

Further information:

Dr. Yang Zhang
e-Mail: zhangy@uni-bremen.de
https://www.geo.uni-bremen.de/page.php?pageid=102&benutzer_ID=4935&p_reg=1