A post mid-Cretaceous North Sea model

Bulletin of the Geological Society of Denmark

Rasmussen, E.S. 2000:¹  Dybkjær, K.¹ 

[1] Palynological dating of the Oligocene – Miocene successions in the Lille Bælt area, Denmark. Bulletin of the Geological Society of Denmark, Vol. 47, pp. 87–103, Copenhagen.

关键词: Palynology;    sequence stratigraphy;    Late Oligocene;    Early Miocene;    Hagenør;    Hindsgavl;    Rønshoved;    Lille Bælt;    Denmark.;   

学科分类：地球科学(综合)

来源: Dansk Geologisk Forening

【 摘 要 】

The relative importance and causal relationship between tectonics, eustacy and sediment charge is investigated for the post mid-Cretaceous North Sea. Guided by the predictions of a quantitative model and previously published work it is argued that the geological evolution comprises 1) continued subsidence of the central North Sea and its more marginal basin areas, related to Palaeozoic and Mesozoic lithospheric and deeper processes, 2) Cenozoic uplift of the British Isles (Scotland) and western Fennoscandia initiated by the Iceland plume in Paleocene/Eocene, 3) inversion zone dynamics induced by in-plane stress variations from plate boundary processes (the African-Eurasian collision and Atlantic spreading), and 4) denudation controlled by the availability of topography and erosional base level changes. The processes are consistent with the general present day sediment structure of the North Sea. Furthermore, they produced the pattern and amplitude of the burial anomalies in the North Sea region: 1) the continued subsidence of the central North Sea ensured maximum burial here at the present day, 2) Cenozoic uplift of the coastal areas of Scotland and western Fennoscandia, including southern Norway, produced over-burial that decreases away from the coast with a gradient that depends on the flexural strength of the lithosphere, 3) inversion zones (in particular the Sole Pit High and the Sorgenfrei-Tornquist Zone) developed a two phase burial anomaly, firstly by erosion of the narrow strip of topography in the central zone of inversion, and secondly by more regional erosion of the post-compressional rebound topography, involving both the central inversion zone and the marginal troughs. The falling eustatic level generated a burial anomaly by erosional unloading and isostatic uplift of the basin margins. Deep Quaternary erosion enhanced the burial anomaly in, for example, the Farsund Basin and the Skagerrak. The post-compressional rebound of the Sorgenfrei-Tornquist Zone is identified as the Neogene tectonic mechanism in the eastern North Sea area.

【 授权许可】

Unknown