The parish lies on the
Upper Cretaceous chalk at the northern edge of the
Hampshire Basin, dipping south from the
Winchester anticline, with successively younger beds being exposed from north to south. In the north the Seaford Chalk formation of
Santonian age makes up Compton Down. South of this the Newhaven Chalk outcrops in the
dry valley running down from
Oliver's Battery to Shawford. In the south of the parish the Culver Chalk of
Campanian age is largely overlain by a layer of 'clay-with-flints' weathered out of the chalk. In the east the chalk is cut through by the Itchen valley and overlain by calcareous
tufa. A feature of the geology is the hill immediately southwest of the village of Shawford known as Shawford Down. This area is noted for its rich variety of habitats and the grazed pasture supports a wealth of flora and fauna, including notable insects and wildflowers. ==History==