Structural evolution and basin architecture of the Traill Ø region, NE Greenland: A record of polyphase rifting of the East Greenland continental margin

Fault block basins exposed along NE Greenland provide insights into the tectonic evolution of East Greenland and the Norwegian-Greenland Sea. We present a new geological map and cross sections of the Traill Ø region, NE Greenland, which formed the western margin of the Vøring Basin prior to Cenozoic seafloor spreading. Observations support a polyphase rift evolution with three rift phases during Devonian-Triassic, Jurassic-Cretaceous, and Cenozoic time. The greatest amounts of faulting and block rotation occurred during Cenozoic rifting, which we correlate with development of the continent- ocean transition after ca. 56 Ma and the Jan Mayen microcontinent after ca. 36 Ma. A newly devised macrofaunal-based stratigraphic framework for the Cretaceous sandy mudstone succession provides insights into Jurassic- Cretaceous rifting. We identify a reduction in sedimentation rates during the Late Cretaceous; this corresponds to a transition from structurally confined to unconfined sedimentation that coincides with increased clastic sedimentation to the Vøring and Møre Basins derived from East Greenland. With each rift phase we record an increase in the number of active faults and a decrease in the spacing between them. We attribute this to fault block rotation that leads to an excess build-up of stress that can only be released by the creation of new steep faults. In addition, we observe a stepwise migration of deformation toward the rift axis that we attribute to preexisting lithospheric heterogeneity that was modified during subsequent rift and post-rift phases. Such observations are not readily conformable to classic rift evolution models and highlight the importance of post-rift lithospheric processes that occur during polyphase rift evolution

Structural evolution and basin architecture of the Traill Ø region, NE Greenland: A record of polyphase rifting of the East Greenland continental margin

Fault block basins exposed along NE Greenland provide insights into the tectonic evolution of East Greenland and the Norwegian-Greenland Sea. We present a new geological map and cross sections of the Traill Ø region, NE Greenland, which formed the western margin of the Vøring Basin prior to Cenozoic seafloor spreading. Observations support a polyphase rift evolution with three rift phases during Devonian-Triassic, Jurassic-Cretaceous, and Cenozoic time. The greatest amounts of faulting and block rotation occurred during Cenozoic rifting, which we correlate with development of the continent- ocean transition after ca. 56 Ma and the Jan Mayen microcontinent after ca. 36 Ma. A newly devised macrofaunal-based stratigraphic framework for the Cretaceous sandy mudstone succession provides insights into Jurassic- Cretaceous rifting. We identify a reduction in sedimentation rates during the Late Cretaceous; this corresponds to a transition from structurally confined to unconfined sedimentation that coincides with increased clastic sedimentation to the Vøring and Møre Basins derived from East Greenland. With each rift phase we record an increase in the number of active faults and a decrease in the spacing between them. We attribute this to fault block rotation that leads to an excess build-up of stress that can only be released by the creation of new steep faults. In addition, we observe a stepwise migration of deformation toward the rift axis that we attribute to preexisting lithospheric heterogeneity that was modified during subsequent rift and post-rift phases. Such observations are not readily conformable to classic rift evolution models and highlight the importance of post-rift lithospheric processes that occur during polyphase rift evolution

The New Zealand Fossil Record File: a unique database of biological history

© 2020 The Royal Society of New Zealand. The New Zealand Fossil Record File, an essentially complete compilation of New Zealand’s known fossil record, with additional records from parts of Antarctica, SW Pacific, and elsewhere, is, to the best of our knowledge, unique. It has developed collaboratively, with contributions from university, government, industry, and avocational paleontologists and geologists. The distinctive Fossil Record Number has become an icon of New Zealand geological literature since inception of the original paper-based archive in the 1940s. Subsequently, the file has been digitised and currently holds >100,000 locality records and >1,000,000 individual taxonomic identifications spanning numerous plant and animal phyla. These numbers are continually growing. The database contains contextual information on geographic location, collection, stratigraphy and lithology of the fossil localities as well as taxonomic analyses that retain original identifications yet accommodate re-assignments. The data have been widely applied, initially for mapping, establishing age, depositional environment, etc., and more recently including in quantitative biostratigraphy, assessing completeness of the fossil record, understanding biodiversity history, extinction risk assessments, and climate analysis. In this paper, we provide a brief overview of the history of the Fossil Record File, indicate the general nature of the data it contains, and showcase a number of innovative applications of this most valuable resource