Chronology of Tertiary fan deposits off the western Barents Sea: Implications for the uplift and erosion history of the Barents Shelf

Eidvin, Tor; Jansen, Eystein; Riis, Fridtjof

doi:10.1016/0025-3227(93)90164-q

Cited by 108 publications

(59 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The location of crossing profiles is indicated by red triangles. section are attributed to Late Cenozoic uplift and erosion (Eidvin et al, 1993;Grogan et al, 1999;Ohm et al, 2008;. Erosion has removed up to 3200 m from the sedimentary section in the northwestern end of the profile and about 1600 m in the southeastern end (e.g.…”

Section: Crustal Structurementioning

confidence: 99%

Crustal structure and evolution of the Arctic Caledonides: Results from controlled-source seismology

et al. 2017

View full text Add to dashboard Cite

Section: Crustal Structurementioning

confidence: 99%

Crustal structure and evolution of the Arctic Caledonides: Results from controlled-source seismology

et al. 2017

View full text Add to dashboard Cite

“…The SvalbardBarents Sea platform represents more than 1 million km 2 of drainage area, and the 2-4-km-thick late Cenozoic glaciogenic wedges along the margin indicate extensive glacial erosion of the platform, varying from 0.5 km in the south to 1.5 km in the northwest (Eidvin et al, 1993;Faleide et al, 1996;Solheim et al, 1996a) (Fig. 2).…”

Section: Background and Objectivesmentioning

confidence: 99%

Site 986

1996

Proceedings of the Ocean Drilling Program, 162 Initial Reports

View full text Add to dashboard Cite

Principal results: Four holes were drilled at Site 986 (SVAL-1), with a maximum penetration of 964.6 mbsf. The sequence penetrates all the main regional reflectors (R1-R7) of the Svalbard-Barents Sea margin, with good ties to the reflectors and main seismic sequences shown by core physical property measurements and wireline logging. This major objective was successfully reached, enabling a documentation of the main phases of glacial erosion and deposition on the margin. The sediments recovered are predominantly fine-to coarse-grained siliciclastics with varying amounts of gravel. Dropstones (> 1.0 cm in size) are abundant in most cores of the upper sedimentary sequence (0-561.8 mbsf). Sedimentary rocks are common among the dropstones throughout this sequence, whereas igneous and/or metamorphic rock fragments are more common in the interval from 380 to 550 mbsf. Over 500 dropstones greater than 1.0 cm in size are present from 2.58 through 845.3 mbsf. High methane content in the rapidly deposited sediments and high dropstone content lead to variable recovery. However, all main units are documented by recovery, and important additional information from wireline logging of the upper 500 m of the sequence enables a comprehensive description of the formations, consisting of four lithostratigraphic units. A composite section was developed for the upper 210 mcd of Site 986, providing relative alignments between adjacent holes but confirmed overlap was maintained only through the top 60 mcd.

show abstract

“…In this communication, we focus on the stratigraphy, tectonic features and events including Triassic and younger (Figures 2 and 3), with the focus on the following key sequences and boundaries: (1) present-day seabed, marked by numerous fluid escape features [15,16], (2) the Upper Regional Unconformity (URU) [43]: a diachronous angular unconformity marking the erosional base of multiple glacial episodes (0.8 Ma [16,20,44,45]); (3) a Cenomanian-Campanian polygonal fault interval [17]; and (4) the Bajocian Stø Formation, the main reservoir of the Snøhvit, Albatross and Askeladd fields [9,13]. Figure 2.…”

Section: Geological and Structural Settingmentioning

confidence: 99%

Role of Faults in Hydrocarbon Leakage in the Hammerfest Basin, SW Barents Sea: Insights from Seismic Data and Numerical Modelling

2017

View full text Add to dashboard Cite

Hydrocarbon prospectivity in the Greater Barents Sea remains enigmatic as gas discoveries have dominated over oil in the past three decades. Numerous hydrocarbon-related fluid flow anomalies in the area indicate leakage and redistribution of petroleum in the subsurface. Many questions remain unanswered regarding the geological driving factors for leakage from the reservoirs and the response of deep petroleum reservoirs to the Cenozoic exhumation and the Pliocene-Pleistocene glaciations. Based on 2D and 3D seismic data interpretation, we constructed a basin-scale regional 3D petroleum systems model for the Hammerfest Basin (1 km × 1 km grid spacing). A higher resolution model (200 m × 200 m grid spacing) for the Snøhvit and Albatross fields was then nested in the regional model to further our understanding of the subsurface development over geological time. We tested the sensitivity of the modeled petroleum leakage by including and varying fault properties as a function of burial and erosion, namely fault capillary entry pressures and permeability during glacial cycles. In this study, we find that the greatest mass lost from the Jurassic reservoirs occurs during ice unloading, which accounts for a 60-80% reduction of initial accumulated mass in the reservoirs. Subsequent leakage events show a stepwise decrease of 7-25% of the remaining mass from the reservoirs. The latest episode of hydrocarbon leakage occurred following the Last Glacial Maximum (LGM) when differential loading of Quaternary strata resulted in reservoir tilt and spill. The first modeled hydrocarbon leakage event coincides with a major fluid venting episode at the time of a major Upper Regional angular Unconformity (URU,~0.8 Ma), evidenced by an abundance of pockmarks at this stratigraphic interval. Our modelling results show that leakage along the faults bounding the reservoir is the dominant mechanism for hydrocarbon leakage and is in agreement with observed shallow gas leakage indicators of gas chimneys, pockmarks and fluid escape pipes. We propose a conceptual model where leaked thermogenic gases from the reservoir were also locked in gas hydrate deposits beneath the base of the glacier during glaciations of the Hammerfest Basin and decomposed rapidly during subsequent deglaciation, forming pockmarks and fluid escape pipes. This is the first study to our knowledge to integrate petroleum systems modelling with seismic mapping of hydrocarbon leakage indicators for a holistic numerical model of the subsurface geology, thus closing the gap between the seismic mapping of fluid flow events and the geological history of the area.

show abstract

Chronology of Tertiary fan deposits off the western Barents Sea: Implications for the uplift and erosion history of the Barents Shelf

Cited by 108 publications

References 13 publications

Crustal structure and evolution of the Arctic Caledonides: Results from controlled-source seismology

Crustal structure and evolution of the Arctic Caledonides: Results from controlled-source seismology

Site 986

Role of Faults in Hydrocarbon Leakage in the Hammerfest Basin, SW Barents Sea: Insights from Seismic Data and Numerical Modelling

Contact Info

Product

Resources

About