The course of the northern drainage system suggests that it initially flowed NW into the Cretaceous/Palaeocene Nuussuaq Basin, before being redirected SW around the West Greenland Igneous Province in the Mid-Palaeocene. Hydrological analysis of Greenland’s isostatically balanced basement topography outlines two major drainage systems that likely flowed across Greenland prior to the onset of glaciation and emptied into the Sisimiut Basin within the Davis Strait, offshore West Greenland. The onshore and offshore stratigraphy of Central West Greenland outlines the presence of a major fluvial system that existed during the Cretaceous and was later redirected in the Early Cenozoic by the formation of the West Greenland Igneous Province. During rifting and partial breakup sedimentary basins formed that record the changing regional sediment supply. The Mesozoic-Cenozoic separation of Greenland and North America produced the small oceanic basins of the Labrador Sea and Baffin Bay, connected via a complex transform system through the Davis Strait. Supplementary material: Isostatic modelling, hydrological analysis and chi mapping is available at: This work highlights the importance of large pre-glacial drainage systems across North Atlantic passive margins and their relevance when studying post-rift stratigraphy in rifted margin settings. This scenario provides a greater understanding of the West Greenland margin's late Cenozoic evolution, which differs from previous interpretations that hypothesize a period of considerable post-rift tectonism and uplift. Moreover, characteristics of these two drainage systems suggest they acted as a single larger fluvial system, prior to the onset of glaciation, that was likely the primary source of sediment across Central West Greenland throughout the Cretaceous and Palaeogene. Hydrological analysis of Greenland's isostatically balanced basement topography outlines two major drainage systems that likely flowed across Greenland prior to the onset of glaciation and emptied into the Sisimiut Basin within the Davis Strait, offshore West Greenland. The Mesozoic–Cenozoic separation of Greenland and North America produced the small oceanic basins of the Labrador Sea and Baffin Bay, connected via a complex transform system through the Davis Strait. This work highlights the how interaction of rift tectonics and isostasy can be the principal source for modern elevated continental margins, while also providing insight into the pre-rift exhumational history of central Laurentia. These results suggest the source of the Cumberland Peninsula's modern-day elevated topography is uplift during rifting in the Cretaceous and the isostatic compensation following continuous Mesozoic and Cenozoic differential erosion. Pre-rift cooling is interpreted as the result of exhumation of Laurentia, syn-rift cooling as the result of rift flank uplift to the SE and Downloaded from differential erosion of landscape, while the final post-rift period is likely an artefact of the modelling process. The spatial distribution of AFT and AHe ages implies exhumation has been significant toward the SE (Labrador) coastline, while results of thermal modelling outline three notable periods of cooling in the pre-rift (460 Ma-200 Ma), from syn-rift to present (120 Ma-0 Ma) and within post-rift (30 Ma-0 Ma) stages. This work combines the original AFT data with 98 apatite new (U-Th)/He ages from 16 samples and applies the newly developed 'broken crystals' technique to provide a greater number of thermal constraints for thermal history modelling to better constrain the topographic evolution. Apatite fission track (AFT) analysis of the landscape previously concluded that the area has experienced a differential protracted cooling regime since the Devonian however, defined periods of cooling and the direct causes of exhumation were unresolved. ![]() ![]() The Cumberland Peninsula, Baffin Island, formed as the result of rifting along the Labrador-Baffin margins in the late Mesozoic and is dominated by low relief high elevation topography. Elevated topography is evident across the continental margins of the Atlantic.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |