Resumé
Apatite fission-track analysis (AFTA) data in two Upper Jurassic core samples from the 231 m deep Blokelv-1 borehole, Jameson Land, East Greenland, combined with vitrinite reflectance data and regional AFTA data, define three palaeo-thermal episodes. We interpret localised early Eocene (55- 50 Ma) palaeotemperatures as representing localised early Eocene heating related to intrusive activity whereas we interpret late Eocene (40-35 Ma) and late Miocene (c. 10 Ma) palaeotemperatures as representing deeper burial followed by successive episodes of exhumation. For a palaeogeothermal gradient of 30°C/km and likely palaeo-surface temperatures, the late Eocene palaeotemperatures require that the Upper Jurassic marine section in the borehole was buried below a 2750 m thick cover of Upper Jurassic - Eocene rocks prior to the onset of late Eocene exhumation. As these sediments are now near outcrop at c. 200 m above sea level, they have been uplifted by at least 3 km since maximum burial during post-rift thermal subsidence. The results are consistent with estimates of rock uplift on Milne Land since the late Eocene and with interpretation of Ocean Drilling Program (ODP) data off South-East Greenland suggesting that mid-Cenozoic uplift of the margin triggered the marked influx of coarse clastic turbidites during the late Oligocene above a middle Eocene to upper Oligocene hiatus.
Originalsprog | Engelsk |
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Sider (fra-til) | 133-147 |
Antal sider | 15 |
Tidsskrift | Geological Survey of Denmark and Greenland Bulletin |
Vol/bind | 42 |
DOI | |
Status | Udgivet - 28 dec. 2018 |
Programområde
- Programområde 3: Energiressourcer