The Late Cenozoic Eridanos delta system in the Southern North Sea Basin: a climate signal in sediment supply?

The Eridanos fluvio-deltaic system, draining most of north-western Europe, developed during the Late Cenozoic as a result of simultaneous uplift of the Fennoscandian shield and accelerated subsidence in the North Sea Basin. This seismo-stratigraphic study aims to reconstruct the large-scale depositional architecture of the deltaic portion of the basin fill and relate it to external controls. A total of 27 units have been recognized. They comprise over 62x10 3 km3 in the Southern North Sea Basin alone, and have an average delta surface area of 28x103 km2, which suggests that the size of the drainage area was about 1.1x106 km2. Water depth in the depocentre is seen to decrease systematically over time. This trend is interrupted by a deepening phase between 6.5 and 4.5 Ma that can be correlated with the simultaneous occurrence of increased uplift of the Fennoscandian shield, increased subsidence of the Southern North Sea Basin, and a long-term eustatic highstand. All these observations point to a tectonic control on long-term average rates of accommodation and supply. Controls on short-term variations are inferred from variations in rates of sediment supply and bifurcation of the delta channel network. Both rates were initially low under warm, moist, relatively stable climate conditions. The straight wave-dominated delta front gradually developed into a lobate fluvial-dominated delta front. Two high-amplitude sea-level falls affected the Pliocene units, which are characterized by widespread delta-front failures. Changes in relative sea level and climate became more frequent from the late Pliocene onward, as the system experienced the effects of glacial-interglacial transitions. Peaks in sedimentation and bifurcation rates were coeval with cold (glacial) conditions. The positive correlation between rates of supply and bifurcation on the one hand, and climate proxies (pollen and d18O records) on the other hand is highly significant. The evidence presented in this study convincingly demonstrates the control of climate on time-averaged sediment supply and channel-network characteristics, despite the expected nonuniformity and time lags in system response. The presence of a clearly discernible climate signal in time-averaged sediment supply illustrates the usefulness of integrated seismo-stratigraphic studies for basin-wide analysis of delta evolution on geological time scales.

[1]  F. Riis.  Quantification of Cenozoic vertical movements of Scandinavia by correlation of morphological surfaces with offshore data , 1996 .

[2]  J. Faleide,et al.  Cenozoic sequence stratigraphy of the central and northern North Sea Basin: tectonic development, sediment distribution and provenance areas , 1995 .

[3]  S. Østmo,et al.  Plio-Pleistocene deposits on the mid-Norwegian margin and their implications for late Cenozoic uplift of the Norwegian mainland , 2000 .

[4]  W. E. Galloway,et al.  Genetic Stratigraphic Sequences in Basin Analysis II: Application to Northwest Gulf of Mexico Cenozoic Basin , 1989 .

[5]  H. Kooi,et al.  Lithospheric dynamics and the rapid pliocene-quaternary subsidence phase in the southern north sea basin , 1991 .

[6]  S. Ghazi.  Cenozoic uplift in the Stord Basin area and its consequences for exploration , 1992 .

[7]  B. Funnell.  Plio-pleistocene palaeogeography of the southern north sea basin (3.75-0.60 Ma) , 1996 .

[8]  W. E. Galloway,et al.  Sea Level Events Associated with Lower Oligocene Vicksburg Formation of Texas Gulf Coastal Plain, as Determined from Depositional Systems Analysis: ABSTRACT , 1989 .

[9]  W. B. Harland,et al.  A Geological Time Scale , 1983 .

[10]  E. Jansen,et al.  Paleoenvironmental changes in the Norwegian Sea and the northeast Atlantic during the last 2.8 m.y.: Deep Sea Drilling Project/Ocean Drilling Program Sites 610, 642, 643 and 644 , 1988 .

[11]  Olaf Michelsen,et al.  High-frequency sequence stratigraphy of Upper Cenozoic deposits in the central and southeastern North Sea areas , 1997 .

[12]  J. Wagoner,et al.  High-frequency sequences and their stacking patterns: sequence-stratigraphic evidence of high-frequency eustatic cycles , 1991 .

[13]  O. Eldholm,et al.  Cenozoic uplift of Fennoscandia inferred from a study of the mid-Norwegian margin , 1996 .

[14]  N. Hovius,et al.  INVITED EDITORIAL Clastic sediment supply to basins , 1998 .

[15]  A. Miall.  The geology of stratigraphic sequences , 1996 .

[16]  K. Lidmar-Bergström.  Long term morphotectonic evolution in Sweden , 1996 .

[17]  W. Bull,et al.  Geomorphic Responses to Climatic Change , 1991 .

[18]  L. Jensen,et al.  Late Tertiary uplift and erosion in the Skagerrak area : magnitude and consequences , 1992 .

[19]  T. Törnqvist,et al.  Fluvial responses to climate and sea‐level change: a review and look forward , 2000 .

[20]  A. Whiteman,et al.  Geological atlas of western and central Europe , 1983 .

[21]  G. V. Laursen,et al.  Cenozoic Sequence Stratigraphy in the Eastern North Sea , 1999 .

[22]  P. Gibbard.  The History of the Great Northwest European Rivers During the Past Three Million Years , 1988 .

[23]  N. Eyles.  Earth's glacial record and its tectonic setting , 1993 .

[24]  T. Cronin,et al.  PLIOCENE PALAEOTEMPERATURE RECONSTRUCTION FOR THE SOUTHERN NORTH SEA BASED ON OSTRACODA , 1993 .

[25]  E. Jansen,et al.  Neogene and Pleistocene Glaciations in the Northern Hemisphere and Late Miocene — Pliocene Global Ice Volume Fluctuations: Evidence from the Norwegian Sea , 1990 .

[26]  C. Mesdag,et al.  High resolution seismic profile through a Late Cenozoic delta complex in the southern North Sea , 1993 .

[27]  M. Jervey.  Quantitative Geological Modeling of Siliciclastic Rock Sequences and Their Seismic Expression , 1988 .

[28]  R. Fairbanks,et al.  Tertiary oxygen isotope synthesis, sea level history, and continental margin erosion , 1987 .

[29]  W. E. Galloway,et al.  Genetic Stratigraphic Sequences in Basin Analysis I: Architecture and Genesis of Flooding-Surface Bounded Depositional Units , 1989 .

[30]  K. Knudsen,et al.  Plio-Pleistocene foraminiferal stratigraphy and correlation in the Central North Sea , 1991 .

[31]  R. Reyment,et al.  Statistics and Data Analysis in Geology. , 1988 .

[32]  W. Berggren,et al.  Late Neogene chronology: New perspectives in high-resolution stratigraphy , 1995 .

[33]  F. Bertelsen.  Azolla Species from the Pleistocene of the Central North Sea Area , 1972 .

[34]  William H. Press,et al.  Numerical recipes in C (2nd ed.): the art of scientific computing , 1992 .

[35]  P. A. Ziegler,et al.  Geological atlas of Western and Central Europe , 1969 .

[36]  W. E. Galloway,et al.  Quantitative Determination of Tertiary Sediment Supply to the North Sea Basin , 1997 .

[37]  P. Beek,et al.  The relationship between basin and margin thermal evolution assessed by fission track thermochronology: an application to offshore southern Norway , 1996 .

[38]  H. Kooi,et al.  Intraplate stresses and the post-Cretaceous uplift and subsidence in northern Atlantic basins , 1992 .

[39]  H. Posamentier,et al.  Eustatic Controls on Clastic Deposition II—sequence and Systems Tract Models , 1988 .

[40]  P. Beek,et al.  Meso-Cenozoic morphotectonic evolution of southern Norway: Neogene domal uplift inferred from apatite fission track thermochronology , 1995 .

[41]  P. Molnar,et al.  Late Cenozoic uplift of mountain ranges and global climate change: chicken or egg? , 1990, Nature.

[42]  H. Kooi,et al.  Intraplate stresses and the stratigraphic evolution of the North Sea Central Graben , 1989 .

[43]  Peter Japsen,et al.  Neogene uplift and tectonics around the North Atlantic: overview , 2000 .

[44]  H. Posamentier,et al.  An Overview of the Fundamentals of Sequence Stratigraphy and Key Definitions , 1988 .

[45]  J. M. Coleman,et al.  Deltaic coastal wetlands , 1989 .

[46]  N. Shackleton.  Oxygen isotopes, ice volume and sea level , 1987 .

[47]  William H. Press,et al.  Numerical recipes in C. The art of scientific computing , 1987 .

[48]  N. Opdyke,et al.  Oxygen isotope and palaeomagnetic evidence for early Northern Hemisphere glaciation , 1977, Nature.

[49]  Mike Kirkby,et al.  Process models and theoretical geomorphology , 1994 .

[50]  A. M. Joy.  Right place, wrong time: anomalous post-rift subsidence in sedimentary basins around the North Atlantic Ocean , 1992, Geological Society, London, Special Publications.

[51]  Henry W. Posamentier,et al.  Eustatic Controls on Clastic Deposition I—conceptual Framework , 1988 .

[52]  W. H. Zagwijn.  The Netherlands during the Tertiary and the Quaternary: A case history of Coastal Lowland evolution , 1989 .

[53]  J. Syvitski,et al.  Geomorphic/Tectonic Control of Sediment Discharge to the Ocean: The Importance of Small Mountainous Rivers , 1992, The Journal of Geology.

[54]  C. Ollier,et al.  Landforms and uplift history of southern Norway , 2000 .

[55]  M. Kirkby,et al.  Sediment supply and climate change: implications for basin stratigraphy , 1998 .

[56]  G. Weltje,et al.  Stratigraphic inversion of siliciclastic basin fills: a note on the distinction between supply signals resulting from tectonic and climatic forcing , 1998 .

[57]  K. Glennie.  Introduction to the petroleum geology of the North Sea , 1986 .

[58]  F. Riis.  Dating and measuring of erosion, uplift and subsidence in Norway and the Norwegian shelf in glacial periods , 1992 .

[59]  G. V. Laursen,et al.  Occurrence of major sequence stratigraphic boundaries in relation to basin development in Cenozoic deposits of the southeastern North Sea , 1995 .

[60]  P. Konradi.  Foraminiferal biostratigraphy of the post-mid-Miocene in the Danish Central Trough, North Sea , 1996, Geological Society, London, Special Publications.

[61]  U. Gregersen,et al.  Factors controlling the Cenozoic sequence development in the eastern parts of the North Sea , 1999, Journal of the Geological Society.

[62]  H. Friis.  Weathered heavy-mineral associations from the young-Tertiary deposits of Jutland, Denmark , 1974 .

[63]  C. Payton.  Seismic Stratigraphy — Applications to Hydrocarbon Exploration , 1977 .

[64]  F. Gradstein,et al.  Cenozoic foraminiferal and dinoflagellate cyst biostratigraphy of the central North Sea , 1992 .

[65]  I. Gibson.  Statistics and Data Analysis in Geology , 1976, Mineralogical Magazine.