Depositional evolution of a progradational to aggradational, mixed-influenced deltaic succession: Jurassic Tofte and Ile formations, southern Halten Terrace, offshore Norway
File(s)
Accepted version
Author(s)
van Cappelle, M
Ravnås, R
Hampson, GJ
Johnson, HD
Type
Journal Article
Abstract
Predicting the hydrodynamics, morphology and evolution of ancient deltaic successions requires the evaluation of the three-dimensional depositional process regime based on sedimentary facies analysis. This has been applied to a core-based subsurface facies analysis of a mixed-energy, clastic coastal-deltaic succession in the Lower-to-Middle Jurassic of the Halten Terrace, offshore mid-Norway. Three genetically related successions with a total thickness of 100–300 m and a total duration of 12.5 Myr comprising eight facies associations record two initial progradational phases and a final aggradational phase. The progradational phases (I and II) consist of coarsening upward successions that pass from prodelta and offshore mudstones (FA1), through delta front and mouth bar sandstones (FA2) and into erosionally based fluvial- (FA3) and marine-influenced (FA4) channel fills. The two progradational phases are interpreted as fluvial- and wave-dominated, tide-influenced deltas. The aggradational phase (III) consists of distributary channel fills (FA3 and FA4), tide-dominated channels (FA5), intertidal to subtidal heterolithic fine-grained sandstones (FA6) and coals (FA7). The aggradational phase displays more complex facies relationships and a wider range of environments, including (1) mixed tide- and fluvial-dominated, wave-influenced deltas, (2) non-deltaic shorelines (tidal channels, tidal flats and vegetated swamps), and (3) lower shoreface deposits (FA8). The progradational to aggradational evolution of this coastal succession is represented by an overall upward decrease in grain size, decrease in fluvial influence and increase in tidal influence. This evolution is attributed to an allogenic increase in the rate of accommodation space generation relative to sediment supply due to tectonic activity of the rift basin. In addition, during progradation, there was also an autogenic increase in sediment storage on the coastal plain, resulting in a gradual autoretreat of the depositional system. This is manifested in the subsequent aggradation of the system, when coarse-grained sandstones were trapped in proximal locations, while only finer grained sediment reached the coastline, where it was readily reworked by tidal and wave processes.
Date Issued
2016-11-15
Date Acceptance
2016-11-14
Citation
Marine and Petroleum Geology, 2016, 80, pp.1-22
ISSN
0264-8172
Publisher
Elsevier
Start Page
1
End Page
22
Journal / Book Title
Marine and Petroleum Geology
Volume
80
Copyright Statement
© 2016 Elsevier Ltd. All rights reserved. This manuscript is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/
Sponsor
Shell International Exploration & Production Inc.
Grant Number
PO 4550080818
Subjects
Science & Technology
Physical Sciences
Geosciences, Multidisciplinary
Geology
Ror Formation
Fangst Group
Facies analysis
Mixed energy delta
Tide dominated
Tide influenced
BREMSTEIN FAULT COMPLEX
BURDEKIN RIVER DELTA
LOWER SEGO SANDSTONE
NORTHERN NORTH-SEA
FERRON NOTOM DELTA
COAST TIDAL FLAT
MID-NORWAY
STRATIGRAPHIC ARCHITECTURE
BRITISH-COLUMBIA
HEIDRUN FIELD
0403 Geology
0404 Geophysics
Publication Status
Published