Mid-Jurassic age for the Botany Bay Group: implications for Weddell Sea Basin creation and southern hemisphere biostratigraphy Morag A. Hunter David J. Cantrill Michael J. Flowerdew Ian L. Millar 10.6084/m9.figshare.3454298.v1 https://geolsoc.figshare.com/articles/dataset/Mid-Jurassic_age_for_the_Botany_Bay_Group_implications_for_Weddell_Sea_Basin_creation_and_southern_hemisphere_biostratigraphy/3454298 <p>New U–Pb zircon ion-microprobe ages from the alluvial conglomerates and flood plain sediments of the Botany Bay Group demonstrate that sedimentation occurred at <strong><em>c.</em></strong> 167 Ma, coeval with rift-related silicic volcanism in the northern Antarctic Peninsula. In contrast, rift-related volcanism and sedimentation in the southern Antarctic Peninsula (Latady Basin) occurred at <strong><em>c.</em></strong> 183 Ma. The new data indicate that syn-rift sedimentation and volcanism was diachronous from south to north, consistent with early opening of the Weddell Sea embayment by anti-clockwise rotation of the Antarctic Peninsula in the Mid-Jurassic. A definitive date for the Botany Bay Group floras has important implications for Southern Hemisphere biostratigraphic correlations. </p> 2016-06-21 12:02:00 Weddell Sea embayment Weddell Sea Basin creation Southern Hemisphere biostratigraphic correlations Ma sedimentation Antarctic Peninsula Botany Bay Group floras Botany Bay Group volcanism implication Geology