Interaction between faulting and sedimentation during Dinantian extension of the Solway basin, SW Scotland

Abstract

The ENE-WSW-trending North Solway Fault acted as a northern marginal fault to the Solway Basin during Dinantian sedimentation. Structural, sedimentological and diagenetic relationships suggest syn-sedimentary Dinantian movement was dip-slip and normal. A later Carboniferous phase of dextral transtension is also indicated. Allokinetic deformation features increase in abundance and intensity towards the North Solway Fault, their presence and nature being strongly facies dependent. Syn-sedimentary fault deformation of the hanging wall sediments also increases towards this fault. Both distributed and localized shearing characterizes these early faults and is thought to be related to the water content of beds at the time of deformation. Local minor thrusting and reverse fault movement also occurred within the sediments during basin extension, due to dextral transtensional movement on the North Solway Fault. N-S-and NW-SE-trending faults appear to show no evidence for syn-sedimentary Dinantian movement and are interpreted as the products of 'Hercynian' basin shortening and Mesozoic basin formation.

Sedimentary Facies and Soft-sediment Deformation Structures in the Late Miocene-Pliocene Middle Siwalik Subgroup, Eastern Himalaya, Darjiling District, India

“…Fluidization and liquefaction of sediment, which are the main mechanisms for such deformation structures (cf. Allen and Banks, 1972), can be triggered either by the sedimentation process itself (including the action of gravity on active bedforms; Jones and Rust 1983) or by earthquake shock (e.g., McKee et al 1962;Rust, 1968;Seilacher, 1969;Turner, 1981;Allen, 1985;Røe, 1987;Ord et al 1988;Seth et al, 1990;Røe and Hermansen, 1993;Wells et al 1993;cf. Bhattacharya and Bhattacharya, 2005 and references therein).…”

Influence of basement on the geometry of Permo-Triassic basins in the northwest British Isles

“…As the southern margin of the Southern Uplands, the ENE-WSW North Solway Fault represents the limit to Dinantian sedimentation in Northern England (Ord et al 1988;Gawthorpe et al 1989). Following Carboniferous-Permian inversion, Permo-Triassic sedimentation was controlled by reactivation of the ENE-WSW fault trend .…”

Fluid migration history in the north Irish Sea-North Channel region

“…It is possible to examine rocks at the faulted margins of Carboniferous and Permo-Triassic basins in southern Scotland. (Deegan 1973;Ord et al 1988). Facies distributions and soft-sediment deformation features clearly indicate that the fault was active during the Dinantian.…”

“…NW-SE faults which have clear geomorphological expressions as coastal inlets and inland valleys occur in Wigtown Bay and Auchencairn Bay. These two faults bound Permo-Triassic offshore in Wigtown Bay (Jackson & Mulholland 1993) and displace the NE-SW North Solway Fault (Ord et al 1988), respectively.…”