Lower carboniferous (Dinantian) stratigraphy and structure in the Kingscourt Outlier, Ireland

摘要: Logging of 55 recent boreholes, together with remapping, has resulted in a fundamental reassessment the stratigraphy and sedimentology Dinantian Kingscourt Outlier. Despite present isolated position outlier within Longford-Down Massif, rocks are an integral part Dublin Basin succession. The newly defined Ardagh Platform marks most northerly limit to basinal sedimentation Basin. The Courceyan is typical but thinner, north succession two new formal units: Rockfield Sandstone Member Kilbride Formation. latter, coarse-grained, well washed limestone latest early Chadian (late Tournaisian) age shallow water equivalent Feltrim Formation (Waulsortian facies), which absent outlier. interval markedly attenuated. In succeeding Chadian-Brigantian facies predominate south, on almost complete coeval Visean sequence found. A platform unit (Deer Park Formation) Asbian Brigantian area. Dee (Chadian) for lower Tober Colleen Altmush Shale formally upper Loughshinny Formation. Two major structures dominate Outlier: NE-SW trending Moynalty Syncline south N-S Fault. Both Hercynian structures, probably represent reactivated Caledonide basement-controlled structures. syn-depositional faulting indicated both (‘Kingscourt Sag’) Chadian-Asbian. latter period area separates from south. late Asbian, carbonate build-ups prograded into basin as far Nobber, Brigantian, extended northwards over collapsed margin.