Slump‐initiated and controlled syndepositional sandstone remobilization: an example from the Namurian of County Clare, Ireland

Sedimentology - Tập 49 Số 1 - Trang 25-41 - 2002
Lorna J. Strachan1
11 Department of Earth Sciences, Cardiff University, PO Box 914, Cardiff CF10 3YE, UK (E‐mail: [email protected])

Tóm tắt

Remobilization of sandstones can dramatically reconfigure original depositional geometries and results in very unusually shaped sandstones, which resemble little, if any, of the original geometry. A number of deformational sandstone bodies, dykes and volcanoes from the upper part of the Carboniferous Ross Formation are described, which offer the opportunity to examine a suite of field‐scale reconfigured sandstones. These structures are located in close proximity to the Ross Slide, which outcrops along a 2‐km section on the northern coast of the Loop Head Peninsula, County Clare, Ireland. Dome‐ and ridge‐shaped deformational sandstone bodies, dykes and volcanoes are interpreted to be the product of remobilization of a turbiditic sandstone. Liquification and remobilization were triggered by translation, cessation and loading of the underlying turbiditic sandstone by the Ross Slide. Deformational sand body, dyke and volcano development occurred in an asynchronous fashion with deformational sand bodies formed during slump translation. Sand dykes and volcanoes developed after the cessation of slump movement. During slump translation, the minimum principal stress (σ3) was orientated vertically and the slump behaved in a `ductile' manner. After slump arrest, the minimum principal stress was oriented horizontally, and the unit regained shear strength to behave in a `brittle' manner. The relative change in rheological states with changing applied shear stress is indicative of thixotropic‐like behaviour within the slump mass. Ridge‐shaped deformational sand bodies are aligned parallel to slump folds, and their morphology is inferred to be controlled by compressional slump deformation associated with heterogeneous cessation of slump movement that was initiated by frontal arrest of the translating mass.

Từ khóa


Tài liệu tham khảo

Allen J.R.L.(1982)Sedimentary Structures: Their Character and Physical Basis Vol. II. Elsevier Amsterdam 663 pp.

Archer J.B., 1984, Clastic intrusions in deep‐sea fan deposits of the Rosroe Formation, Lower Ordovician, Western Ireland, J. Sed. Petrol., 54, 1197

Bakken B.(1987)Syn‐depositional Deformation and Sedimentology of the Uppermost Ross Formation Western Irish Namurian Basin Ireland. Unpubl. Cand. Scient. Thesis University of Bergen Norway 182 pp.

Brooke C.M. Trimble T.J.andMackay T.A.(1995)Mounded shallow gas sands from the Quaternary of the North Sea: analogues for the formation of sand mounds in deep water Tertiary sediments. In:Characterization of Deep Marine Clastic Systems(Eds A.J. Hartley and D.J. Posser) Geol. Soc. London Spec. Publ. 94 95–103.

Chapin M.A. Davies P. Gibson J.L.andPettingill H.S.(1994)Reservoir architecture of turbidite sheet sandstones in laterally extensive outcrops Ross Formation Western Ireland.GCSSEPM Foundation 15th Annual Research Conference on Submarine Fans and Turbidite Systems pp. 53–68.

Collinson J.D.(1994)Sedimentary deformational structures. In:The Geological Deformation of Sediments(Ed. A. Maltman) 1st edn pp. 95–124. Chapman & Hall London.

10.1111/j.1365-2117.1991.tb00131.x

Dixon R.J. Schofield K. Anderton R. Reynolds A.D. Alexander R.W.S. Williams M.C.andDavies K.G.(1995)Sandstone diapirism and clastic intrusion in the Tertiary submarine fans of the Bruce‐Beryl Embayment Quadrant 9 UKCS. In:Characterization of Deep Marine Clastic Systems(Eds A.J. Hartley and D.J. Posser) Geol. Soc. London Spec. Publ. 94 77–94.

10.1130/0091-7613(2000)28<119:MESATI>2.0.CO;2

10.1016/0191-8141(84)90012-9

Farrell S.G.andEaton S.(1987)Slump strain in the Tertiary of Cyprus and the Spanish Pyrenees. Definition of palaeoslopes and models of soft‐sediment deformation. In:Deformation of Sediments and Sedimentary Rocks(Eds M.E. Jones and R.M.F. Preston) Geol. Soc. London Spec. Publ. 29 181–196.

Gill W.D., 1979, Syndepositional sliding and slumping in the West Clare Namurian Basin, Ireland, Geol. Survey Ireland, Spec. Paper, 4, 1

Gill W.D., 1958, Sand volcanoes in slumps in the Carboniferous of Co. Clare, Eire, Q. J. Geol. Soc. London, 113, 414

10.1080/00288306.1969.10420236

Hiscott R.N., 1979, Clastic sills and dykes associated with deep‐water sandstone, Tourelle Formation, Ordovician, Quebec, J. Sed. Petrol., 49, 1

10.1016/0040-1951(76)90014-7

Martinsen O.J.(1989)Styles of soft‐sediment deformation on a Namurian delta slope Western Irish Namurian Basin Ireland. In:Deltas: Sites and Traps for Fossil Fuels(Eds M.K.G. Whateley and K.T. Pickering) Geol. Soc. London Spec. Publ. 41 167–177.

10.1144/gsjgs.147.1.0153

Martinsen O.J. Lien T.andWalker R.G.(2000)Upper Carboniferous Deep Water Sediments Western Ireland: Analogues for Passive Margin Turbidite Plays.GCSSEPM Foundation 20th Annual Research Conference on Deep‐Water Reservoirs of the World pp. 533–555.

Nichols R.J.(1995)The liquefaction and remobilization of sandy sediments. In:Characterization of Deep Marine Clastic Systems(Eds A.J. Hartley and D.J. Prosser) Geol. Soc. London Spec. Publ. 94 63–76.

10.1111/j.1365-3091.1994.tb01403.x

Pulham A.J.(1989)Controls on internal structure and architecture of sandstone bodies within Upper Carboniferous fluvial‐dominated deltas County Clare western Ireland. In:Deltas: Sites and Traps for Fossil Fuels(Eds M.K.G. Whateley and K.T. Pickering) Geol. Soc. London Spec. Publ. 41 179–203.

Rider M.H.(1969)Sedimentological Studies in the West Clare Namurian Ireland and the Mississippi River Delta.Unpubl. PhD Thesis Imperial College London.

Rider M.H., 1974, The Namurian of West County Clare, Proc. Roy. Irish Acad., 74, 125

Rider M.H., 1978, Growth Faults in Carboniferous of Western Ireland, AAPG Bull., 62, 2191

Shanmugam G., 1994, Slump and debris‐flow dominated upper slope facies in the Cretaceous of the Norwegian and northern North Seas (61–67°N): implications for sand distribution, AAPG Bull., 78, 910

10.1680/geot.1952.3.1.30

Stow D.A.V. Reading H.G.andCollinson J.D.(1996)Deep Seas. In:Sedimentary Environments: Processes Facies and Stratigraphy(Ed. H.G. Reading) 3rd edn pp. 395–451. Blackwell Science Oxford.

10.1002/gj.3350230202

Strogen P. Somerville I.D. Pickard N.A.H. Jones G.L.L.andFleming M.(1996)Controls on ramp platform and basinal sedimentation in the Dinantian of the Dublin Basin and Shannon Trough Ireland. In:Recent Advances in Lower Carboniferous Geology(Eds P. Strogen I.D. Somerville and G.L.L. Jones) Geol. Soc. London Spec. Publ. 107 263–279.

Taylor B.J., 1982, Sedimentary dykes, pipes and related structures in the Mesozoic sediments of south‐eastern Alexander Island, Br. Antarctic Survey Bull., 51, 1

Waterhouse J.B., 1957, Redeposition and slumping in the Cretaceous‐Tertiary strata of South East, Wellington, Trans. Roy. Soc. NZ, 83, 519

10.1046/j.1365-2117.2000.00113.x