Geology
The southern part of the parish was originally a natural salt marsh adjacent to the River Thames which is tidal and saline at this point. Decaying vegetation together with mud and silt from the river were deposited from the end of the most recent ice age until the marshes were reclaimed sometime before the 14th century. These sedimentary deposits reach a depth of fifty feet or more and are interleaved with a number of peaty layers.
About two miles north of the river, the land rises steeply to a ridge that provides excellent views over the marshes and out to the Downs of Kent. This is one of the finest gravel beds in the country and has been extensively worked. The higher (and dryer) ground extends north for roughly another mile. The north west of Chadwell lies at the end of the chalk outcrop.
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