500 000 10 20 30 40 50 60 70 80 906 00000 10 20 30 40 NW LIMIT OF ANGLIAN SE BGS publications covering Essex, Southend-on-Sea, Thurrock (5) and the ICE SHEET Inferred subcrop of London Boroughs of Barking & Dagenham (3), Havering (4), Redbridge (2) Carboniferous Limestone and Waltham Forest (1) beneath Mesozoic rocks Foxearth (Pt, Sg) Glacial sand and gravel Report 97 Report 118 250 205 206 Lowestoft Till Hoe Lane (Sg) Kesgrave Plateau Buried soil horizon Glaciofluvial sand and gravel reworking Report 133 Report 82 Report 68 report 85 Report 11 Report 8 Glacial sand B EDR and gravel Head Gravel Thin Brickearth Little Chishill 1 O CK 222 223 ESSEX River terrace PEDL36 Alluvium Crag River Terraces CANUK Crag Great Chesterford (Sg) Saltmarsh Report 104 Report 109 Report 16 Report 102 Report 10 Report 14 (comprising Essex, Southend-on-Sea, Thurrock, Tidal Flats Sea Level Walden Road (Ch) Sub-alluvial Sand London Boroughs of Barking & Dagenham, Lambeth Group and Gravel Buried Channel (Woolwich and Report 112 Report 46 Report 52 Report 6 Report 2 Report 7 224 Reading Beds) Havering, Redbridge and Waltham Forest) Thames Group (London Clay, Sub-alluvial gravel Chalk (High purity) Harwich Formation) Buried Channel Mineral Resource Information in Support of National, Thanet Sand Formation Report 67 Report 66 Report 13 Report 4 Regional and Local Planning Rectory Farm (Sg) 40 40 2 Little Walden Road (Ch) Mineral Resources 00 Goldingham Hall (Sg) 239 240 241 242 Grange Farm (Sg) Report 34 Scale 1:100 000 Report 43 Bulmer (Cl) Schematic section showing form and relationship of mineral resources in Essex (not to scale) 1 2 Compiled by A.J. Bloodworth, A. Benham, M. Shaw, S.J. Mathers, D.G. Cameron, 4 Southend-on-Sea S. Hobbs, D.J. Evans, G.K. Lott and D.E. Highley. 3 Report 36NW Project Leader: D.E. Highley. 256 5 Report 36NE 5 6 257 258 259 Digital cartography by N.A. Spencer, British Geological Survey. 50 00 Mill Farm (Soil) Great Sampford (Ch) Published 2002. Petroleum Exploration and Development Licence issued Hydrocarbon Well PEDL under the Petroleum (Production) Act 1934 (as at August 2001) Alphamstone (Cl) 271 272 This map comprises part of a summary of the 'Mineral Resources of the East of England Region'. HYDROCARBON AND SUBSURFACE AGGREGATE POTENTIAL Maiden-Ley (Sg) Ferriers Farm (Sg) For further information see www.mineralsUK.com 240 Report 16 Conventional oil and gas Wicken Road (Sg) 1:25 000 map published (Industrial Minerals Kilowen House (Cl) 1:63 360 and 1:50 000 map published Chalk Farm Quarry (Ch) Harrow Cross (Sg) Assessment Sand and Gravel Resource Map) Essex lies on the northern margin of the Wales-Brabant Massif, across which Mesozoic source and reservoir rocks are BIBLIOGRAPHIC REFERENCE thin or absent and have not been buried to the depths required for the generation of hydrocarbons. The paucity of Harwich Rail Bloodworth, A J, and 8 others. 2002. Mineral Resource Information in Support of National, Regional and Local Planning: Essex exploration wells and the absence of a network of seismic reflection surveys, illustrates that the county has little or no oil Tilekiln Quarry Report 43 Current digital availability of these sheets can be found at the 1:25 000 map published (comprising Essex, Southend-on-Sea, Thurrock, London Boroughs of Barking & Dagenham, Havering, Redbridge and Waltham Forest. and gas potential. The sketch map shows one current exploration licence, PEDL36 straddling the Essex/Cambridgeshire Aggregates British Geological Survey website www.bgs.ac.uk (Foxborough Hills) (Sg) (Applied Geology Map) British Geological Survey Commissioned Report CR/02/127N. boundary. This is held and operated by CANUK. Little Chishill l, drilled in 1966 by BP, remains the only hydrocarbon Terminal (Sg) exploration well in the county of Essex. Hollow Road (Widdington) (Sg) Old Packards Lane (Sg) Production of this map was commissioned and funded by the Office of the Coal Mine Methane, Abandoned Mine Methane and Coalbed Methane (CBM) potential White Colne Brickworks (Sg) 30 Hollow Road (Sg) Wells Farm (Sg) 30 Deputy Prime Minister (Contract MP0677). There is little or no potential for these forms of methane as coal-bearing strata are absent. White Colne Brickworks (Sg) Armigers Farm (Sg) Beazley End (Sg) Wick Farm (Sg) Badliss Hall Farm (Sg) COMMON CLAY (including BRICK CLAY and BRICKEARTH) Subsurface aggregate potential White Colne (Sg) Braintree Road (Sg) 'Brick clay' is the term used to describe clay and shale used predominantly in the manufacture of bricks and, to a lesser Carboniferous limestone is the most extensively used crushed rock aggregate in England. It is generally a high quality Bollington & Wades Farm (Sg) Martells (Sg, SiS) extent, roof tiles and clay pipes. These clays may sometimes be used in cement making, as a source of constructional fill SAND & GRAVEL material which is used for both concreting aggregate and roadstone. Although there are currently no operations in the UK Ugley Park (Sg) and for lining and sealing landfill sites. The suitability of a clay for the manufacture of bricks depends principally on its which extract aggregate from underground, this production method remains an option for the future. Between the Wash Wash Farm (Sg) behaviour during shaping, drying and firing. This will dictate the properties of the fired brick such as strength and frost Superficial deposits and north London, boreholes prove isolated areas of Carboniferous Limestone subcropping beneath the Mesozoic Elsenham Sand Quarry (Sg) resistance and, importantly, its architectural appearance. unconformity. The sketch map shows one such area of Carboniferous Limestone subcrop which lies in the south-east of Alsa Lodge (Sg) Elsenham Sand Quarry (Sg) Seven Arches Farm (Sg) Cambridgeshire near the boundary with Essex. The limestone subcrop is poorly constrained and could extend beneath Allens Fm Reservoir (Sg) Hall Farm Borrow Pit (Sg) Most facing bricks, engineering bricks and related clay-based building products are manufactured in large automated Sub-alluvial: Inferred resources Essex. Subsurface information indicates that across Essex, the base Mesozoic surface dips generally south-east from Alsa Street (Sg) Land Lane (Sg) factories. These represent a high capital investment and are increasingly dependent, therefore, on raw materials with depths of 150 m below sea level in the north west of the county to around 400 m around Southend. Given these depths, predictable and consistent firing characteristics in order to achieve high yields of saleable products. Blending different Down Farm (Sg) the most favourable areas for possible underground working of aggregates are likely to be in the north west of the county, clays to achieve improved durability and to provide a range of fired colours and textures is an increasingly common Sub-alluvial: Indicated resources (only in area assessed by BGS) Straits Mill (Sg) close to the known subcrops of Carboniferous (Dinantian ?) limestone in Cambridgeshire. However, aggregate potential is feature of the brick industry. Continuity of supply of consistent raw materials is of paramount importance. low since the limited amount of information available suggests that these limestones are dolomitised and are relatively Duck Street & Ravens Farm (Sg) London Road (Sg) Hall Farm (Sg) Marks Tey (Cl) poor quality aggregate raw materials. A brick manufacturing site at Marks Tey, west of Colchester, uses Quaternary-age interglacial lake clay blended with clays River Terrace deposits Farnham (Ch) Hatches Farm (Sg) Lower Lodge Fen Farm (Sg) Cowlands Farm (Sg) Stanway (Sg) Hill Farm (Sg) imported from outside the county to produce facing bricks. Blake House Farm (Sg) Goulds Farm (Sg) Straight Road (Sg) Farm (Sg) Licensing Wivenhoe (Sg) Rayne Road (Sg) In the Southend area, brickearth formed the basis for a number of brickworks manufacturing distinctive golden yellow River Terrace deposits: Concealed (only in area assessed by BGS) Little Easton Merks Hill Farm (Sg) Colchester Old Heath (Sg) The Department of Trade and Industry grants licences for exclusive rights to explore and exploit oil and gas onshore Frogs Hall Farm (Sg) Airfield (Sg) Bluegates & Tenpenny Farm (Sg) 'London Stock' bricks. 'Brickearths' are silty loams which are usually found in association with river gravels in the area within Great Britain. The rigths granted by landward licences do not include any rights of access, and the licensses must (Bellhouse) (Sg) Thremhall Priory Farm (Sg) Donyland Lodge (Sg) around the Thames Estuary. Deposits are generally thin (less than 2 m), but can be persistent, particularly where also obtain any consent under current legislation, including planning permissions. Licensees wishing to enter or drill Broadfields Farm Hockley Farm Reservoir (Sg) associated with extensive river terrace and flood plain sediments. Today, only one brickworks remains, although this Glaciofluvial sand and gravel (including Kesgrave Formation) Scripps Farm (Sg) Villa Farm (Sg) Thorpe-le-Soken (Sg) through coal seams for coalbed methane and abandoned mine methane must also seek the permission of the Coal Staggs Farm (Sg) Borrow Pit (Sg) Bradwell Pit (Sg) traditional brick is now much in demand, particularly for restoration and conservation work in London. The map shows the Rowhedge Pits (Sg) Brook Farm (Sg) Authority. Poplars Chase Farm (Sg) distribution of brickearth in the Southend area only. Canfield (Sg) Glaciofluvial sand and gravel: Concealed (only in area assessed by BGS) Barnston (Sg) Fingringhoe Alresford (Sg) Although the outcrop area of the Palaeogene ('Tertiary') age London Clay is extensive in Essex, this clay is not shown as a 20 (Frogs Hall) (Sg) Thors Farm (Sg) resource since it is generally unsuitable for use in modern brickmaking processes. This is due to the presence of relatively 20 Glacial sand and gravel deposits Alresford Creek (Sg) high levels of the clay mineral montmorillonite. However, the London Clay is used for brickmaking at a small operation at CHALK Birch Pit (Sg) Wick Lane (Sg) Bulmer in the north of the county and was formerly used as a raw material for the manufacture of lightweight expanded Silver End (Sg) Great Holland (Sg) clay aggregate in the Ongar area.