A revision of the lithostratigraphical classification of the early Palaeogene strata of the London Basin and East Anglia

Abstract

Current multidisciplinary research on the Palaeogene strata in the London Basin and East Anglia has been given impetus by the drilling of several key boreholes for stratigraphical purposes, and for major construction projects in the London area. Improved rotary coring over the past five years or so has resulted in virtually complete recovery of Palaeogene successions. These cores have formed the basis for building on established research in order to provide a formal lithostratigraphical framework appropriate for academic and practical use. A new formation, the Ormesby Clay Formation, is introduced for argillaceous sediments in East Anglia equivalent to the Thanet Sand Formation of the London Basin. The term Lambeth Group is introduced, replacing the 'Woolwich and Reading Beds' and thereby allowing the beds to be defined in formations. Thus the former ‘Bottom Bed’ is named Upnor Formation and the overlying strata are divided into a Woolwich Formation and a Reading Formation. The dominantly arenaceous and pebbly beds between the Lambeth Group and London Clay Formation, including strata traditionally known as the Oldhaven Beds, Blackheath Beds, and ‘London Clay basement bed’ and the ash-bearing beds in the northeast of the London Basin and East Anglia, are grouped together as the Harwich Formation.