Thurrock

The following sites have been selected to represent the different aspects of geology and landscape in the district. Not all sites have something to see; many are solely of historical interest as a record of an important or interesting discovery.

Some sites are not strictly geological but have a geological connection. Geological sites are therefore defined in their widest sense and include, for example, buildings, walls, wells, spas, springs, graves, boreholes, plaques, landslips and viewpoints.

This is not a complete list of geological sites in the district. Others will be added and descriptions expanded as further research is carried out.

Important note:
Not all of the sites here described are accessible. Some sites are on private land and can only be viewed from footpaths that pass through or alongside the site. Inclusion of a site on this list does not, therefore, imply any right of access. Please remember not to trespass on private land.

Sites of Special Scientific Interest (SSSIs)

AVELEY. A13 Road Cutting SSSI (TQ 556 799)
During excavation for the A13 trunk road to the south of Aveley in 1997 a sequence of Ice Age sediments were found that were equivalent to those that contained the fossil elephants at Sandy Lane Pit directly to the north. Excavations for the cutting beneath the Purfleet Road bridge provided a revealed a cold-climate gravel at the base overlain by fossiliferous sands and clays (known as the Aveley Silts and Sands). The upper part of the interglacial sequence was represented by two layers of clay rich in vertebrates, molluscs, insects, plant remains and pollen indicating that the climate was at least as warm as the present day. The whole sequence is capped by sand and gravel indicating a return of very cold conditions. The interglacial represented here is the same as that represented at Sandy Lane Pit and therefore about 200,000 years old (in recognition of this site this interglacial stage is often called the ‘Aveley Interglacial’). Bones of a range of mammals were found such as brown bear, wolf, giant deer, mammoth, straight-tusked elephant, rhinoceros, horse, bison and a very large lion. Of particular interest was the first discovery in Britain of the bones of a ‘jungle cat’. Although grassed over, the road cutting can be seen from the Purfleet Road bridge.

CHAFFORD HUNDRED. Lion Pit Tramway Cutting SSSI (part of Chafford Gorges Nature Park) (TQ 598 781)

This site, part of an old tramway cutting created in the nineteenth century to transport chalk from Lion Pit to the riverside wharves, provided an excellent section through Ice Age sediments which are banked up against an ancient riverside chalk cliff that existed here about 200,000 years ago. These river deposits span a period of deposition from one glacial stage through to the next which includes the intervening interglacial stage, at the beginning of which there were early humans here, making stone tools on the gravel beach below the cliff. Evidence of human occupation has been flint knapping debris in the lower gravel which is undisturbed. Remarkably it has actually been possible to refit some flakes together, which proves that humans were actually manufacturing stone tools here. The humans occupying the site were Neanderthals. The tramway cutting has also produced the fossil bones of several species of mammals such as brown bear, rhinoceros, bison, mammoth and straight-tusked elephant. The sides of the cutting are now grassed over.

GRAYS. Globe Pit SSSI (TQ 625 783)
Globe Pit in Whitehall Lane is of geological importance because of the occurrence, on the eastern side of the pit, of Corbets Tey Lower Gravel containing abundant Palaeolithic flint tools, above which is a brickearth that was formerly very fossiliferous. The gravel and the brickearth were deposited by the River Thames when it flowed through here about 350,000 years ago. These Thames deposits sit on top of the Thanet Sand, which in turn lies on top of the Chalk which is exposed on the floor of the quarry. The flint tools in the gravel are known as ‘Clactonian’ and represent an industry that was first recognised in the cliffs at Clacton and that is based on flint flakes and cores rather than hand-axes. Globe Pit is also important because the brickearth is virtually all that remains of the celebrated ‘Grays brickearth’, a fine grained silt containing fossil shells which was a rich source of spectacular Ice Age fossil mammals. Surviving remnants of this deposit are valuable as no modern studies of its small vertebrate fossils has ever been carried out, studies which could yield much information about the fauna and climate of this little understood period of the Ice Age. There is no access to the site for casual visitors but visits are sometimes arranged for organised groups.

PURFLEET. Purfleet Chalk Pits SSSI (TQ 569 786 (Greenlands Quarry))

Greenlands Quarry at Purfleet (sometimes called Dolphin Pit) is of critical importance for interpreting the sequence of events in the Lower Thames valley during the middle of the Ice Age. Here, sediments are banked up against the northern side of the Purfleet anticline, an east-west ridge formed by a fold in the Chalk strata, and contain a record of three separate periods of early human occupation that makes this site unique in Britain. The first is a cold climate gravel at the base followed by warm climate sediments and capped by gravel representing a return to cold or glacial conditions. Based on the fossils and other evidence geologists have concluded that the warm climate sediments were laid down by the Thames during an as yet unnamed interglacial stage (provisionally called the ‘Purfleet Interglacial’ after this site) that is thought to be over 280,000 years old. Fossils found include the bones of deer, bison, monkey, beaver and straight-tusked elephant, and a single 3 centimetre diameter coprolite (fossilised faeces) of a hyena. Three adjacent disused quarries (Bluelands Quarry, Botany Pit and Esso Pit) also form part of the Purfleet Chalk Pits SSSI. For safety and security reasons the Greenlands Quarry section is not accessible to the public and is only accessed via a locked gate in Armor Road. Visits, however, are periodically arranged for organised groups.

Local Geological Sites (LoGS)

No LoGS have yet been notified in the district as the notification process is still underway.

Other Sites

AVELEY. Belhus Woods Country Park (TQ 565 825)
Straddling the border between Thurrock and the London Borough of Havering, Belhus Woods Country Park contains many lakes that were originally gravel pits. The area is situated on the Lynch Hill terrace of the Thames, which contains Corbets Tey Gravel, deposited by the river about 280,000 years ago. The old gravel workings, formerly known as Hunts Hill Farm and Whitehall Wood Pits, have fortunately been spared ‘landscaping’; therefore most of the pits still retain their original profiles with some gravel and sand still visible in the banks.

AVELEY. Kennington Park & Sandy Lane Pit (site of) (TQ 560 812 and TQ 553 807)
Kennington Park (TQ 560 812) was created from gravel pits alongside the Romford Road and the former pits are now attractive fishing lakes. There are several exposures of gravel, particularly alongside the path on the northern edge of the park where it forms low cliffs up to 2 metres high. The gravel is Orsett Heath Gravel which forms the oldest and highest terrace of the Thames (the Boyn Hill Terrace) and is thought to be about 380,000 years old. To the west is the famous Sandy Lane Clay Pit (TQ 553 807) where, in 1964, the remains of a mammoth and a juvenile straight-tusked elephant were discovered in Ice Age deposits channelled into the London Clay (Sandy Lane Pit has now been infilled).

CHAFFORD HUNDRED. Chafford Gorges Nature Park (TQ 599 793) (Visitor Centre)
Chafford Gorges Nature Park is the finest area for geology in south Essex. Spectacular cliffs of Upper Chalk can be seen which are a legacy of quarrying for the Portland Cement industry. The Chalk is overlain by Thanet Sand and gravels from former routes of the Thames during the Ice Age. There are also several fine sarsen stones around the rim of Grays Gorge. The park consists of seven geological sites (Grays Gorge, Lion Gorge, Lion Pit Tramway Cutting SSSI, Millwood Sand Cliff, Sandmartin Cliff, Warren Gorge and Wouldham Cliff), which are under the control of Essex Wildlife Trust. Lion Pit Tramway Cutting SSSI is one of the most important of the County’s SSSIs, yielding evidence of human occupation on the banks of the Thames 200,000 years ago. The visitor centre has fine views overlooking Warren Gorge. A geological trail guide is available.

FOBBING. Vange Mineral Well (TQ 700 863)
In the parish of Fobbing, not far from the Five Bells interchange at Vange, are the remains of a curious domed structure, which originally resembled a temple. Although the building was originally built on open land, it is now situated in Martinhole Wood, which is part of Langdon Hills Country Park. It is now sadly a ruin but in the early twentieth century it was the centre of a widely publicised mineral water business.

GRAYS. Grays Park (TQ 618 781)
The town of Grays developed around the brick-making industry which was once of great economic importance to the area and produced spectacular fossils of Ice Age mammals such as mammoth and straight-tusked elephant, lion, brown bear, hyena, rhinoceros, monkey, bison, and beaver. The undulating ground in various parts of Grays is the only evidence today of this industry. The sunken ground of Grays Park, a disused brick pit purchased by Grays Town Council in 1898, is a good example of this.

GRAYS. Hangmans Wood Deneholes (TQ 631 794)
Hangman’s Wood contains the most extensive a best preserved set of deneholes in existence. Deneholes are thought to be medieval chalk mines and consist of vertical shafts through the Thanet Sand and end in branching chambers cut into the underlying chalk. The Hangman’s Wood deneholes are particularly deep, the shafts being over 20 metres deep before the Chalk is reached. There are up to 70 deneholes here but almost all are infilled. Those that are open are fenced. The site is a biological SSSI for the bat colony.

GRAYS. The Dell
Former home of Alfred Russel Wallace (1823-1913), zoologist, botanist, geologist and anthropologist, was one of the greatest scientific minds in Victorian Britain. He is most well known as the co-discoverer, with Charles Darwin, of the laws of evolution by natural selection. Wallace built the house and lived here from 1872 to 1876. The house is still in existence at the very end of College Avenue and is part of the adjacent convent school. It is provided with a heritage plaque to commemorate its famous former resident.

GRAYS. Thurrock College Sarsen Stone (TQ 635 788)
A fine sarsen stone (1.3 metres by 1.1 metres in size) is standing upright on the grass in front of Thurrock College. Until recently, the stone was lying flat on the paving by the college entrance. The stone has fine mammillated surfaces on both sides. Permission to examine the stone should be obtained from the college reception.

LANGDON HILLS. Langdon Hills Country Park (TQ 683 866)
London Clay and Claygate Beds with Bagshot Sand capping the highest ground. This in turn is capped by Stanmore Gravel (formerly called ‘pebble gravel’), the origin of which is still not fully understood. Disused sand and gravel pits exist in the woods. Fine views over the Thames Estuary. Part of the site is in Basildon District.

NORTH STIFFORD. North Stifford Puddingstone (TQ 605 803)
A puddingstone boulder (0.75 metres x 0.60 metres in size) supports the north-west corner of St. Mary’s Church. The boulder consists of layers of black flint pebbles set in a sarsen matrix. This is the only known example of a puddingstone in south Essex.

PURFLEET. Purfleet Submerged Forest. (TQ 5445 7871)
Part of a submerged forest, between 5,000 and 6,000 years old, consisting of fallen tree trunks and roots, is exposed on the Thames foreshore. This site and other submerged forests along the Thames (e.g. at Rainham nearby) have been studied since 1665. This site has educational importance in the interpretation of sea level changes since the end of glacial conditions some 10,000 years ago. The forest can be seen only at low tide.

SOUTH OCKENDON. Brickbarn Wood (TQ 586 799 to 589 799)
One of the finest collections of sarsen stones in the country is situated in Brickbarn Wood and the adjacent Combe Wood on the south side of the Mardyke Valley adjacent to the cutting of the A13 trunk road. It is estimated that as many as 40 stones may be present, most of them partially buried in soil from old gravel pits. Many of the stones are over 2 metres long and have fine mammilated surfaces. Private woodland. Access is available with permission of the landowner. The two woods are a local Wildlife Site.

SOUTH OCKENDON. Davy Down Sarsen Stone (TQ 592 800)
Davy Down Riverside Park forms part of the Mar Dyke Valley, a delightful valley with steep, wooded sides and a grazed floor that can be seen from the M25 motorway. The valley runs along the northern side of the Purfleet Anticline, an east-west trending ridge of chalk between Purfleet and Grays. Also of interest at Davy Down is the pumping station, built in 1928 with a 50 metre deep borehole down into the Chalk. It is still used today for pumping water for use in the local area. Outside the pumping station is a remarkable sarsen stone – probably the finest example in Essex. The sarsen is 1.6 metres square and has fine mammillated surfaces. It formerly stood outside Marley’s works on the south side of Stifford Road, South Ockendon and is understood to have been found in the gravel pit south of the works.

SOUTH OCKENDON. St. Nicholas Church (TQ 594 828)

The construction of round church towers (there are six in Essex) came about because of the difficulty of making satisfactory corners with natural unknapped flints. Probably the best example of a round tower in Essex is St. Nicholas Church, South Ockendon.

WEST THURROCK. Dolphin Chalk Quarry (TQ 571 780)
Formerly known as the Metropolitan Works Quarry, the Dolphin Chalk Quarry is situated between Stonehouse Lane and Canterbury Way (the Dartford Tunnel approach road) and contains a cement manufacturing plant and an industrial estate. The 20 metre (65 foot) high vertical chalk face that forms the western side of the quarry is the most remarkable chalk cliff in Essex as it shows regularly spaced bands of flint nodules which represent cycles of climate change (Milankovitch climate cycles) during the Cretaceous period some 80 million years ago. These flint bands are not present elsewhere in Essex and, due to aspect and differential weathering, are not even clearly visible in the adjoining quarry.

WEST THURROCK. Lakeside (Tunnel Cement Works Quarry) (TQ 585 780)
Lakeside Shopping Centre occupies the floor of the former giant Tunnel Cement Works chalk quarry. In 1968 the Tunnel Cement Works was the largest in Western Europe with 1,200 employees. Steep and vertical faces of chalk are still visible today around the edges of the old quarry with clear bands of flint nodules. However, several faces are covered in geotextiles to prevent falling rock and most are fenced off or otherwise inaccessible. Currently the best and most accessible chalk face is on the south side, off Motherwell Way (behind IKEA). Access is best through the Cliffside Trading Park, open to the public during office hours, where the face can be seen between Units 6 & 7 (TQ 585 780).

WEST THURROCK. Tesco Distribution Centre Quarry (TQ 570 781)
Tesco’s new distribution centre occupies the southern part of Greenlands Quarry (see under Purfleet) and is accessed from Dolphin Quarry via Dolphin Way through a tunnel under the A1090 (Stonehouse Lane). Fine chalk cliffs encircle the building but the cliff on the north side is of particular interest as the top two thirds is coombe rock, a shattered chalk which is direct evidence of extremely cold climate during the last glacial period.

WEST TILBURY. Gun Hill (also called Broom Hill) (TQ 656 780)

The ridge of high ground between West Tilbury and Chadwell St. Mary is a high terrace of the present Thames and to the south the land falls steeply down to the Tilbury Marshes. On this ridge, at the high point known as Gun Hill (also known as Broom Hill) is a private disused gravel pit with exposures of Orsett Heath Gravel, the oldest and highest of the Thames terraces. The layers of sand and gravel were laid down by the River Thames some 380,000 years ago in the middle of the Ice Age. The gravel is now some 25 metres above the level of the present Thames, an excellent example of the erosion that has taken place over this period of time. This is demonstrated by the fine view that can be had from here across the Tilbury Marshes to the modern river. The site is, in effect, a fossil cliff line and is well placed to explain the loop of the Thames around Tilbury.

The Davy Down Sarsen Stone, near South Ockendon. Photo © G.Lucy