. . "Gravel. Stratified superficial deposits. Occurs onshore. Formed during the Early Pleistocene - to - Mid Pleistocene (Quaternary Period) (2.58-.126 Ma BP)."@en . "Chorleywood Gravel Member"@en . "CWGR"@en . "stable"@en . "Chorleywood Gravel Member"@en . "Gravel."@en . "0.126"^^ . . . . "2.58"^^ . .