The Corallian Group (Upper Jurassic) of Wiltshire, England. 3: Lyneham to Royal Wootton Bassett

New information from boreholes at Lyneham and the construction of a relief road south of Royal Wootton Bassett has been combined with field mapping to produce the first synthesis of the transition between the Upper Jurassic shelf sediments of the Wessex Basin and the laterally equivalent clay facies sediments overlying the East Midlands Microcraton. Periodic uplifts of the Wootton Bassett High at the northern margin of the Wessex Basin saw the repeated attempts to spread clay facies sedimentation southwards into central and southern Wiltshire frustrated by uplifts of the high. This resulted in periods of erosion followed by new episodes of shallow water shelf sedimentation succeeded by deeper water strata, these beds resting upon the eroded edges of the older sediments.