Jurassic syn-rift sedimentation on a seawards-tilted fault block, Trail Ø, North-East Greenland

Henrik Vosgerau, Peter Alsen, Ian D. Carr, Jens Therkelsen, Lars Stemmerik, Finn Surlyk

Publikation: Bidrag til tidsskriftArtikelForskningpeer review

12 Citationer (Scopus)

Resumé

Middle-Late Jurassic rifting in East Greenland was marked by westwards tilting of wide fault blocks bounded by major N-S-trending east-dipping synthetic faults. The syn-rift successions thicken westwards towards the faults and shallow marine sandstones show mainly southwards axial transport directions. An exception to this general pattern is found in south-east Traill Ø, which constitutes the E-tilted Bjø rnedal Block, which is bounded to the west by the westwards-dipping antithetic Vælddal Fault. The stratigraphic development of the Jurassic succession on this block shows important differences to the adjacent areas reflecting a different tectonic development. Shallow marine sand seems initially to have filled accommodation space of the immediately adjacent block to the west. This block subsequently acted as a bypass area and much of the sediment was spilled eastwards onto the hangingwall of the east-dipping Bjørnedal Block. The succession on the Bjørnedal Block shows an eastwards proximal-distal decrease in sandstone-mudstone ratio, reflecting increasing water depth and progressive under-filling of the subbasin towards the east in agreement with the dip direction of the fault block. The transverse, mainly south-eastwards palaeocurrents, the eastwards increase in water depths and decrease in sandstone-mudstone ratio on the Bjørnedal Block are at variance with the standard picture of west-tilted blocks with southwards-directed palaeocurrents and decrease in grain size. Earlier palaeogeographic reconstructions have to be modified to account for the east-dipping hanging-wall and different stratigraphic development of the area. The sea was thus open towards the east and there is no direct indication of a barrier or shoal east of Traill Ø.

OriginalsprogEngelsk
Sider (fra-til)9-18
Antal sider10
TidsskriftGeological Survey of Denmark and Greenland Bulletin
Vol/bind5
DOI
StatusUdgivet - 1 nov. 2004

Programområde

  • Programområde 3: Energiressourcer

Fingeraftryk

Dyk ned i forskningsemnerne om 'Jurassic syn-rift sedimentation on a seawards-tilted fault block, Trail Ø, North-East Greenland'. Sammen danner de et unikt fingeraftryk.

Citationsformater