The Gault-Lower Greensand Junction and the Lower Gault of the Maidstone By-Pass (East Section), Kent

Abstract

The Gault-Lower Greensand Junction and the Lower Gault exposed in temporary sections cut during the construction of the maidstone By-Pass (East Section) in north Kent are described. From field evidence it is confirmed that the apparent gap in the Lower Gault sequence in the Maidstone-Bearsted area reported by Spath and H. J. W. Brown does not exist. The phosphatic nodule beds of the Gault-Lower Greensand Junction classified with the mammillatum and basal dentatus Zones are overlain by about twenty-six feet of clays belonging to the Lower Gault. The dentatus-spathi, intermedius, niobe, and subdelaruei Subzones are present in ascending order. There follows the meandrinus Subzone, a name proposed for the upper nodule bed of Bed IV and the base of Bed V at Folkestone and their lateral equivalents. The lautus-nitidus Subzone and a thin representative of the daviesi Subzone follow, underlying a bed of phosphatic nodules belonging to the cristatum Subzone. A comparison is made with the sections at Folkestone and Greatness and certain depositional features in the Lower Gault are discussed.