"37.7"^^ . . "Headon Formation"@en . "Clay with subsidiary sand and trace lignite and limestone. Stratified bedrock. Occurs onshore. Deposited during the Bartonian Age (Palaeogene Period) (41-37.7 Ma BP)."@en . . "41.0"^^ . "Headon Formation"@en . "stable"@en . . "Underlain by Becton Sand of the Barton Group."@en . . . . "Overlain by Bembridge Limestone Formation."@en . "65m"@en . "Headon Beds [Obsolete: use HE]"@en . . "The basal 8.6m (formerly Lower Headon Beds) comprise pale greenish grey clays, some of which contain freshwater shells. Some sands are present and carbonaceous clays and lignite occur toward the base. The middle 10m (formerly Middle Headon Beds, renamed Lyndhurst Member) consists of grey brown and greeniss grey clays and sands with some lignite and freshwater limestone. The highest beds (Upper Headon Beds) comprise pale greenish grey clays and sand."@en . "HE"@en . .