Geology Site Account

Site name: Havering Ridge (includes Havering Country Park and Bedfords Park)

Grid reference: TQ 513931

Brief description of site:

Site of geological interest with potential for promotion of geology. A glacial erratic boulder, recovered from a gravel pit in Romford, sits next to the Bedfords Park Visitor Centre.

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Site description:

The lofty village of Havering-atte-Bower is the highest point of a ridge of high ground that runs across the north of Havering borough. It extends from Havering Country Park in the west, through Havering“atte-Bower, with a spur extending south-east into Bedfords Park.

The geology of the ridge is similar to that of other high points in Essex such as Hainault Forest, High Beach and the Langdon Hills and consists of London Clay overlain by the sandy clay of the Claygate Beds and in turn overlain by Bagshot Sand. These rocks were laid down as sediment on the floor of the London Clay sea some 50 million years ago, the increasingly sandy nature of the strata demonstrating that the sea was slowly becoming shallower.

The highest part of the ridge is capped by a substantial spread of gravel (sometimes called pebble gravel) which also occurs at other high points in Essex, but its origin has puzzled geologists for years. It is now thought to have been laid down probably about a million years ago by northward-flowing tributaries of the early River Thames at a time when the Thames flowed across north Essex and Suffolk. It is difficult to believe that Havering-atte-Bower, now one of the highest points in London, was once the floor of an ancient river valley. The gravel is noticeable in the soil on the high ground of Havering Country Park where it gives rise to birch, gorse and bracken; in contrast to the heavier London Clay soil to the south which favours oak, hornbeam and bramble. During the coldest period of the Ice Age, about 450,000 years ago, the giant Anglian ice sheet spread south into Essex and left behind boulder clay or till. Patches of this distinctive deposit are present on the northern slopes of the ridge and on the high ground of Bedfords Park. In the centre of Havering Country Park a large patch of glacial sand and gravel of similar age has survived which was deposited by glacial melt water possibly in front of the advancing ice sheet.

Springs are evident in many places where groundwater is thrown out at the junction of the Claygate Beds and the impervious London Clay beneath. This is noticeable in Bedfords Park where an area of marsh is fed by springs emerging from the hillside.

On the terrace of Bedfords Park Visitor Centre is a large glacial erratic boulder weighing almost a tonne. It was recovered from Marks Warren Gravel Pit near Romford and brought here by the gravel company. It consists of dolerite and almost certainly originates in Northumberland, brought here by the ice sheet about 450,000 years ago. An interpretive sign has been installed explaining the origin of the boulder.

Havering Country Park and Bedfords Park are both owned by Havering Council. Bedfords Park has a fine new visitor centre run by the Essex Wildlife Trust which commands superb views over East London and Kent.

Glacial erratic boulder and sign at Bedfords Park Visitor Centre