BRITISH GEOLOGICAL SURVEY

TECHNICAL REPORT WA/89/70 Onshore Geology Series

The applied geological mappingof the Dearham and Gilcrux area, Cumbria

1:lO 000 sheets NY 03NE and 13NW:Part of 150000 sheets 22 (Maryport) and 23 (Cockermouth) B Young and M Armstrong

Cover illustration Old pillar-and-stall workings in the Ten Quarters Seam exposed in Oughterside Opencast Site Photo B Young

Geographical index UK, England, Cumbria

Subject index Land-use planning, thematic maps, Quaternary, Carboniferous, Permian, mineral resources, mining, engineering geology

This study was commissionedby the Department of the Environ- ment, but the views expressed in it are not necessarily those of the Department

Maps and diagrams in this report use topography based on Ordnance Survey mapping

Bibliographic reference Young, B, and Armstrong, M. 1989. Theapplied geological mapping of the Dearham and Gilcrux area, Cumbria. British Geological Survey Technical Report WAl89170.

0 NERC copyright 1989 Keyworth,Nottingham British Geological Survey 1989 BRITISH GEOLOGICAL SURVEY

The full range of Survey publications is available through the Keyworth, Nottingham NG12 5GG Sales Desks at Keyworth and Murchison House, Edinburgh. a Plumtree (060 77) 6111 Telex 378173 BGSKEY G Selected items can be bought at theBGS London Information Fax 060 77-6602 Office, and orders are accepted here for all publications. The adjacent Geological Museum bookshop stocks the more popular Murchison House, West Mains Road, Edinburgh EH9 3LA books for sale over the counter. Most BGS books and reports 031-667 1000 Telex 727343 SEISED G are listed in HMSO’s Sectional List 45, and can be bought from Fax s 031-668 2683 HMSO and through HMSO agents and retailers.Maps are listed in the BGS Map Catalogue and the Ordnance Survey’s London Information Office at the Geological Museum, Trade Catalogue, and can be bought from Ordnance Survey Exhibition Road, South Kensington, London SW7 2DE agents as well as from BGS. T 01-589 4090 Fax 01-584 8270 The British Geological Survey carries out the geological survey T 01-938 9056157 of Great Britain and Northern Ireland (the latter as an agency service for the government of Northern Ireland), and of the surrounding continental shelfl as well as its basic research 64 Gray’s Inn Road, London WClX 8NG projects. It also undertakes programmes of British technical aid T 01-242 4531 Telex 262199 BGSCLR G in geology in developing countries as arranged by the Overseas Fax T 01-242 0835 Development Administration. 19 Grange Terrace, Edinburgh EH9 2LF The British Geological Survey is a component body of the s 031-667 1000 Telex 727343 SEISED G Natural Environment Research Council. St Just, 30 Pennsylvania Road, Exeter EX4 6BX T Exeter (0392) 78312

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Parent Body Natural Environment Research Council Polaris House, North Star Avenue, Swindon, Wiltshire SN2 1EU Swindon (0793) 411500 Telex 444293 ENVRE G Fax s 0793-411501 PREFACE

Thisaccount describes the geology of the 1:lO 000 scalesheets NY03hJE and 13NW whichlie within the 150 000 geologicalsheets 22 (Maryport)and 23 (Cockermouth). The resurvey was commissioned by the Department of the Environment with a provision for 50 per cent of the funding. Thearea was firstsurveyed at the six-inch scaleby T V Holmes, R Russell sand J C Ward and published in 1890 and 1892 as Old Series One Inch Sheets 101NE and 101NW respectively. Some revision of Sheet lOlNW was carriedout by J G Goodchildand a new edition of this map was published in 1895. No explanatory memoirs were published foreither sheet. A resurvey of thearea was undertakenby T Eastwoodbetween 1922-26 and 1928-32. New Series geological sheet 22 (Maryport) was published in 1930; sheet 23 (Cockermouth) was published as a Solid edition in 1959 and a Drift edition in 1960. A descriptivememoir for the Maryport sheet was published in 1930 and f0r Cockermouth in 1968. A revision survey at the .1:10,000 scale was carried out in 1986- 87 by M Armstrong (NY03NE) and B Young (NY13NW) with D H Land and D V Frost as ProgrammeManagers. Palaeontological work was carriedout by P Brand and. mineralogical determinations by I Basham and P H A Nancarrow. We are grateful for much help and valuable information provided by British Coal, both the Opencast Executive and deep mines North-Western area, Bothel Limestone sand Co Ltd and numerous land owners.

F G Larminie Director British Geological Survey July 1989 CONTENTS Figures Summary 1 1. Locationmap 2 2. Simplified geological map3 Introduction 4 3. Simplifiedpalaeogeography of theLower Geological histsay 7 Carboniferous6 4. IdealizedYoredale cyclothem 6 Lower Carboniferous Dinantian 7 - 5. Classification of LowerCarboniferous 8 Classification7 6. Generalizedvertical section of Lower Conditions of depositionand sedimentology 10 Carboniferous 9 Stratigraphy13 .- 7. Correlation of Fourth Limestone of the district UpperCarGoniferous - Namurian 15 with the Cockermouth, Caldbeck and northern Classification15 Pennine successions 12 Conditions of depositionand sedimentology 15 8.Generalized vertical section of Namurian 14 Stratigraphy 17 9. Generalizedvertical section of Westphalian 16 Upper Carboniferous- Westphalian 17 . 10. Idealized Coal Measurescyclothem 18 Classification 17 11. Horizontalsections 19 Conditions of depositionand sedimentology 17 12. Quaternarydeposits 20 Stratigraphy 15 13. Rockheadelevation 23 Permo-Triassic 21 14. Driftthickness 24 Classification2 1 Conditions of depositionand sedimentology 21 Stratigraphy 2 1 Tables Structure 21 1. Geologicalsuccession in Gilcrux and Dearham area 5 Mineralisation 22 2. Formercollieries with a take within the Quaternary 25 district 28 Rockhead 25 Quaternarydeposits 25 Associated maps Karstfeatures 27 Maps at 1:25 000 scale Madeground and backfilled opencast sites 30 Structure contours Mineral resources and groundwater 30 Shallow coalworkings (in rear folder) Mineralisation Geological implications for land use planning 34 1 Gromd conditions 34 Thematic maps at 1:IO 000 scale (available Mining 36 separately from the report) Other features to be considered in Location of boreholesNY 03 NE & 13 NW development 37 and shafts Rockheadelevation NY 03 NE & 13 NW Conclusions 39 Driftthickness NENY03 & 13 NW References 40 Swallow holes NY 13 NW Appendix 1. Details ofLower Carboniferous Geological maps at I :IO 000 scale (available (Dinantian) stratigraphy. 42 separately from the report) The maps areoverprinted on Ordnance Survey Appendix 2. Details of Upper Carboniferous topographical bases andproduced for NY03 NW (Namurian) stratigraphy. 45 & 13 NW. Appendix 3. Details of Upper Carboniferous (Westphalian) stratigraphy. 47 Appendix 4. Details of Permo-Triassic stratigraphy. 50 Appendix 5. Details of mineralisation. 50 Appendix 6. Logs of boreholes mentioned in thetext. 52 AppliedGeological Mapping sf Dearham and Gilcrux I

SUMMARY domesticrefuse, covers only a verysmall part of the area. One of thekey objectives of theDepartment of the Environment'sthe Geological Mineraland Extensivecoal mining in the past now places PlanningResearch Programme is the collection restraintson planning and development of the a'nd interpretation of geological informationfor area of the Coal Measuresoutcrop. Subsidence land use planning purposes. fromdeep mining is likely to becomplete but that associatedwith collapse of old workings at Thisaim coincides with the objectives of the shallow depths is difficultto predict. Ancient NaturalEnvironment Research Council,who pillar and stall workings are often less than 30 rn throughthe British Geological Survey, encourage deep and some may be unrecorded. The positions and support research into earth sciences. of someold shaftsare uncertain. and many are The basic tool for suchresearch is a geological likely to have been left untreated or inadequately map. In West Cumbria the first geological survey treatedafter abandonment. The possiblepresence at a 6 inch scale was madein 1878 and revised of unrecordedshallow workings should be taken between 1922 and 1932. The geological accountinto before development any is informationrelating to thisarea was therefore contemplated in areassuch as those near the seriously out of dateand resurvey a was outcrop of coal seams and appropriatesite commissioned with the fundingshared between investigations carried aut. theDepartment of theEnvironment and the Some mudstoneformations in the Lower British Geological Survey. Carboniferous may exhibit bentonitic The geology, mineralresources andgeotechnical characteristics.These may requirethat special aspects of theDearham and Gilcrux areas are consideration is givento the assessment of reassessed using theresurveyed sheets NY 03 NE excavationand foundation conditions anyin and NY 13 NW. proposed development. Thispart of West Cumbria comprisesLower and The till andsand and gravels generally provide Upper Liddesdale Group, formerly known here as good foundationconditions. Other superficial Carboniferous Limestone (Asbian and Brigantian), depositssuch as made ground andalluvium are Hensingham Group,(Namurian) andLower, morevariable and possess weakerengineering Middle and Upper Coal Measures (Westphalian A, properties. Slopes indrift may fail if ~v~~l~adedl B and C). The area's mainmineral product is or over-steepened or if the drift depositsbecome coal which has beenworked underground for locally weakened. severalcenturies. This has now ceased despite Thearea contains resources of coalwhich could some reservesremaining. Opencast working is in beworked by opencast methods. There are als~ operationand useful reserves remain forthe resources of limestone,building stones, fireclays, future.Limestone has also been quarried brickclays, shales andganister inthe area. extensively and is stillworked in one quarry. Resources of samd andgravel are restricted to Reserves exist for future working. smallareas andamounts present are likely to be Quaternarysediments up to 30 mthick conceal limited. much of the solid rocks. Tillor boulder clay Minorbarytemineralisation,vein locally forms the most common superficial deposit and is accompanied by copper minerals, is widespread in of a fairlyuniform composition.Glacial valleys the Dinantianthe and Namuriana rocks. Small cut into the boulder clay are filled with complex quantities of barytes have been mined in the past. drift depositsincluding silts and laminated clays Thearea merits further investigation for possible and often floored by sand and gravel. economicdeposits of barytesand there are some Alluvial andRiver Terrace deposits are extensive grounds for consideringthe possible presence of only inthe Ellen valley. Marineand estuarine barytes and base metal deposits at depth. alluviumoccurs as a minorcomponent of the Widespread mining in thecoalfield has disturbed alluvium in the Crosscanonby area. thenatural hydrogeological regime and potable Raised Beach Deposits,composed principally of groundwater is unlikelyto be obtainedin large sand and gravel, flank the modern beach deposits. quantities. Made Ground, mostly in the form of colliery spoil Domestic refuse is currently used tofill one old andwith smaller amounts of quarry spoil and limestone quarry.The possibility of contaminated A66 Major Roads

0 1 Scale 2 3 Miles I I I I I I 0 i 2 3 4 KIlometres

I I I I I I I

T NY 03 NE’ Allerby ::I... r’ /’

IRISH SEA

MARYPORT

I NX 00 NY IO Figure 1 Location map SBS

------

35 I -I 15

St. Bees Sandstone g - L - Fault v) 0 ----- Coal Middle Coal Measures BQ...... Ten Quarters Lower Coal Measures LA4 ...... Little Main

Hensingham Group Scale First Limestone 0 1 2

/=-j Chief Limestone Group 1 Kilometres t-1 ure t3 Simplified geological map 4 Applied Geological Mapping of Dearhamand Gilcrux leachateescaping into streams at alower level Namurianand Dinantian rocks reach the surface should carefully‘ bemonitored. Any in the central and eastern parts of the district and redevelopment of theinfilled quarry should althoughthe structure iscomplicated by faulting, ensurethat loadbearing walls do notspan the progressivelyolder Binantianrocks crop out in quarrymargins in order toeliminate differential successiontowards thesouth east.Namurian settlement. sedimentsare brought to the surface by faulting ina beltbetween Ellen Bank and Dearham. In TheDinantian and Namurian limestoneoutcrops thenorth west the Westphalian strata (Coal aremarked bynumerous swallow holes. Known Measures) areoverlain by the Triassic St Bees swallowholes areindicated on the mapsthough Sandstone. Much of the CoalMeasures, manyothers may bepresent concealedbeneath Namurianand Triassic outcrops are concealed superficialdeposits. Due consideration should be beneathglacial deposits. Alluvial deposits flank givento the presence of theseand other solution theRiver Ellen along much of itscourse. The cavitiesin the planning of anycivil engineering Dinantian rocks are generally better exposed with projectsgroundon underlain by limestone only thin drift cover. formations. Theregional geology hasbeen summarised by INTRODUCTION Taylor et al. (197 1) and Moseley (1978). Detailed descriptions of thedistrict’s geology have been Thedistrict described in this report lies tothe givenby Eastwood (1930) and Eastwood et al. east of Maryport and to the north of Cockermouth (1968). Modernsummaries of theCarboniferous in the county of Cumbria. It includes the villages stratigraphyare thosebyTaylor (1961) and of Dearham,Crosby, Allerby, Tallentire, Gilcrux Mitchell et al. (1978). Inthe present study the andParsonby (Figure 1). Betweenthese small results of these earlierworks, together with more centres of population the district is predominantly recentinformation from boreholes and mining, ruralwith mixed pastoral andarable farming have all been criticallybeen allreviewedhave and based on numerousscattered farms. Apart from re-correlated. All availablemine plans have been agricultureonlythesignificant sources of examinedand the ground has beenresurveyed in employment within the district today are opencast detail. coal mining at Oughterside, north of Gilcrux and limestone quarryingat Moota, south of Parsonby, Coalmining is along-established industry in the Undergroundmining coalof was formerly districtand dates back several centuries. For the importantin the west,based in andaround the oldestworkings plansno exist. Formany former pitvillages of Dearhamand Crosby. The NineteenthCentury workings plans were either district is servedby the A596,A595 and A594 notmade or have been lost. Many,though by no roads and iscrossed by the Carlisle to Barrowin meansall, of thesurviving Nineteenth Century Furnessrailway line though the nearest stations plans areunreliable tosome extent. Plans of areat Maryport and Aspatria one mile west and Twentieth Century workings in general provide an north east of the district respectively. accuraterecord though inconsistencies are not uncommonbetween different plans of the same Inland from the Solway coast on the south side of workings. The positions of manyold shafts are Allonby Bay thewestern part ofthe district thereforeuncertain. Every effort has beenmade consists of undulatingdrift-covered country tolocate andrecord all shafts as accurately as almost,entirely below 100 mabove sea level. East possible. Undergroundmining came to an end in of linea between Gilcrux and Tallentire the theearly 1950s withthe closure of the district’s ground rises moresharply to broada ridge last collieries at Birkby and Ellenbank. Since then betweenTallentire Hill (223 m), and the highest severalareas have been investigated as opencast point, MootaHill (251 m). Themain drainage is prospectsthough todate extraction has taken to the west through the River Ellen which reaches place only at Qughterside, north of Gilcrux and at the sea at Maryport: a small area on the south side Blooming Heathersouth west of Dearham.Coal of Tallentireand Moota Hills is drained by the extraction at Oughterside ended in July 1988. tributaries of the River Derwent. The district’s most importantextractive industry Themain features of the district’s geology are after coalmining is limestonequarrying. shown in Figure 2. Numerousquarries mark theoutcrop of the The western and northern parts of the district are Dinantianlimestones between Tallentire and part of the West Cumbrian coalfield (Westphalian). Parsonby.Many were small and provided for AppliedGeological Mapping sf Dearhamand Gilcrux 5

STRATUM DEPOSITIONAL APPROX. SYSTEM MAIN LITHOLOGIES N AM E ENVIRONMENT THICKNESS ENVIRONMENT NAME (m\ - .I Colliery spoil, quarry spoil, Madeground material backfilled into opencast - pits, domestic refuse Calcareous tufa I Calcareous tufa I Lime-richsprings andstreams I 0.3to up - BlownSand sand Windsweptlowlandcoastal to ? up 5++ - Raised beach Marine beach formed at deposits Sand and gravel ?upto5* - higher sea level 1

RECENT - -I Lacustrine Freshwater Silt lakes3* to ? up

At junction Of tributary streams Up to 4* de pos its with main with deposits Clay, silt, sand and gravel valleys

Alluvium Clay, sandgravelandsilt,Flood rivers plains of ? up to 5*

River terrace deposits sandSilt,graveland Flood plains of rivers ?to up 4*

Glacial sand and grave I meltwaterGlacialupgravel and Sand to 3 PLEISTOCENE Locally in excess Boulderclay Stony and locally sandy clay Mainly sub-glacial I of 30 n UNCONFORMITY-FOLDING, FAULTING, UPLIFT and EROSION

St. Bees Reddish-brownlaminated and Alluvial plains of large Sandstone 1 cross-beddedsandstone braided rivers Red mudstones with a basal Marine deposition on St.Bees Shalebreccia (known only from up to 80 boreholes) a coastal plain

UNCONFORMITY-FOLDING, FAULTING, UPLIFT and EROSION

Coal Measures

315- 330Ma (First Limestone)(First at base sedimentation Alternating periods of shallow marine 330- Carboniferous Limestones, sandstones, LOWER basin (limestones) and deltaic 345 Ma Limestone mudstonesand Some thincoals incursions(sandstones, mudstones to 31

+c Precise thicknesses of these deposits are unknown in thearea. The figures quoted hereare estimates only.

TABLE 1 GEOLOGICAL SUCCESSION IN THE DEARHAMAND GILCRUX AREA 6 AppliedGeological Mapping sf Dearham and Gilcrux

Figure 3 Simplified palaeogeography of the Lower Carboniferous

DEPOSITIONAL ROCK TYPES ENVIRONMENTS

COAL WITH Swamp SEATEARTH CROSS-BED0IED Alluvial SANDSTONE distributory channels PU R PLE- Prograding LAMINATED Delta platform 'delta SANDSTONE LAMINATED SILTSTONE PiN c Pre-delta sloDe MUDSTONE < LIME-RICH MUDSTONE >Marine shelf LI M ESTONE J

Figure 4 Idealized Yoredale cyclothem AppliedGeological Mapping of Dearham and Gilcrux 7 local needsonly though large quarries were Throughoutmuch of the LowerCarboniferous, worked at Wardhall andHigh Close toproduce limestones, many of which contain abundant shell, bothburnt lime and limestone fluxfor the coral andforaminiferal remains, were deposited Workington Steel Works. Limestone is today over the area. Beds of shale sandstone and locally quarriedon alarge scale at Moota Quarryfor coalthinreflect temporaryincursions of aggregate,roadstone and as araw material for non-marinethe conditions.in Later lime-silica bricks. Carboniferousthis non-marine influence became dominant.NamurianIn times shales and Some otherminerals have been of minorinterest sandstones were deposited in fluviatile and deltaic inthe past. Theseinclude sandstones from both environmentsinand Coal Measures or theCarboniferous and Triassic formations which Westphalian timescoal seams developed from havebeen worked, mainly on a small scale, for equatorialswamp forests. Throughout much of local buildingstone. Small quantities of glacial theCarboniferous, subsidence kept pace with sandand gravel have also beenobtained locally. sedimentationthough there is evidencethat a Trialshave been made on baryte veins in the greateramount of subsidenceoccurred tothe Namurian Hensingham Group west of Gilcrux. north east over the area of the Solway and Carlisle Althoughcoal mining was formerlyextensive in Basin thanover the margins of theLake District thewestern andnorthern parts of the district no Massif to the south. large scale urbandevelopment has takenplace Uplift,folding and faulting tookplace towards here. The relativelylarge ‘pit’ villages of the close of theCarboniferous period and some Dearhamand Crosby developed aroundand near sub-aerialerosion occurred before the deposition tothe collieries but large-scaleindustrial and of thethick sequence of predominantlyred urbandevelopments were concentrated south east sandstones of the Triassic StBees Sandstone. This of thedistrict along the coast south of Maryport. latterformation is believed to representalluvial Todaythese villages servemainly as dormitory plaindeposits laid down by seriesa of large settlements for populationa largely employed braidedstreams. In addition some dune sandsare outside of the district. thoughtto have formed and in places within the St Bees St Sandstonemudstonesred with GEOLOGICAL HISTORY intercalations of salt(halite) are interpreted as The geological succession inthe Dearham and having formed on coastal flats which were subject Gilcruxarea is summarisedin Table 1. With the to periodic evaporation. exception of the Triassic St Bees Sandstone in the Laterdeformation during theTertiary times north west all the solid rocks atoutcrop are of foldedand faulted the StBees Sandstone. There Carboniferous age. No olderrocks have been is no record of further geological events until the penetratedby boreholes but approximately 1 km Quaternary.During this period a late-Devensian SE of the districtthe Lower Carboniferous rocks (between 26 000 and 10 000 BP) glaciation unconformablyoverliesediments of the depositedan extensive mantle of boulder clay Ordovician Skiddaw Group. (till) with local accumulations of sand and gravel. In LowerCarboniferous times the district was Post glacial deposits include alluvial flats adjacent part of ashallow tropical sea onthe northern tomodern streams and beach deposits both of flanks of therecently submerged Lake District which are still forming. Massif of Ordovicianand Silurian sediments, volcanics andintrusives. An episodeof volcanic LOWER CARBONIFEROUS - DINANTIAN activityearly in the local Carboniferoussequence Classification is indicated by theCockermouth Lavas,which cropout approximately 0.5 kmsouth east of the TheDinantian sequence of west Cumbria is districtand which are almostcertainly present dominated by limestone.Individual limestone beneath the eastern part of the district. formationshave long been recognised and known indescending order as theSecond Limestone, ThirdLimestone etc. Their naming in this order datesfrom the early days of west Cumbrianiron Note: Throughout this report national grid oremining when successively lower limestones references are given as 6 or 8 figure co-ordinates. wereencountered inshaft sinking and mine All lie within the lOOkm square NY. development.Strata between limestonesthe comprisemudstones and sandstones: one of the 8 AppliedGeological Mapping of Dearham and Gilcrux

CHRQNOSTRATIGRAPHY LITHOSTRATIGRAPHY

Mitchell et al Eastwoocl et al George et al This Report 1978 1968 1976

NAMURIAN FIRST LIMESTONE

SECONDLIMESTONE

THIRD LIMESTONE

BRIGANTIAN (Zone D2 of UPPER Garwood 191 3) CHIEF UPPER LIMESTONE LIDDESDALE GROUP GROUP

CHIEF DINANTIAN LIMESTONE GROUP

FOURTHLIMESTONE

ASBIAN (Zone Dl of LOWER Garwood 191 3) FIFTH LIMESTONE LQWE R CHIEF LIDDESDALE LIMESTONE GROUP GROUP

SIXTHLIMESTONE

. .- Applied Geological Mappin& of Dearham and Gilcrux 9

SECOND LIMESTONE

OREBANK SANDSTONE -0 - - THIRD LIMESTONE - -

- 50

BRIGANTIAN - UPPER - LIDDESDALE - GROUP -

- 100 Metres

> FOURTH LIMESTONE

I I 1.imestone

J nUndivided ASBIAN FIFTH LIMESTONE -Coal LOWER LIDDESDALE GROUP

SIXTH LIMESTONE

Figure 6 Generalized vertical section of Lower Carboniferous IO AppliedGeological Mapping of Dearham and Gilcrux

sandstones,between the Second andThird weretransported southwards throughout the Limestone is knownas the Orebank Sandstone. Lower Carboniferous. Seven limestone formationsare recognisedin Thepresent district occupies aposition on the Cumbria.The uppermost, the First Limestone, is northernmargin of theManx-Cumbrian-Alston of Namurian age and is described on p 17. In the Ridge. theAt base of the localLower present district the lowest beds at outcrop belong Carboniferoussequence the Cockermouth Lavas to the top few metres of the Sixth Limestone: the areevidence of volcanic activityrepresented by Seventh Limestone does not crop out. several flows of olivine basalt. Thechronostratigraphical and lithostratigraphical The Lower Carboniferoussediments of northern classification of Dinantianthe rocks is England record an interplay of marine and deltaic summarised Figurein 5 and details of the influences.Acyclical repetition of lithologies: sequencepresent inthe district isshown in limestone,mudstone, sandstone and locally coal, Figure 6. Forcorrelations with theLower may beexplained byalternating periods of Carboniferous of other parts of Britain see George relatively slow andrapid subsidence. During the et al. (1976). In this reportthe Geological former period delta lobes advanced across the area Surveyclassification (eg Day 1970) of the fromthenorth depositing mud andsand. Dinantianrocks of theBorder counties into the Occasionally deltaswere builtup to above sea Liddesdalegroups is adopted to enable level so allowing theformation of swampforests comparisons to madebe with other areas. now represented by coal seams. Morerapid Detaileddescriptions of the sequence inthe subsidenceallowed warm clearer water from the district are given in Appendix 1. south to overwhelmthe deltas and led to the deposition of marinelimestones. Thesequence of Conditions of deposition and sedimentology. rocksdeposited during each such cycle of events The basement surfaceon whichtheLower is termedcyclothem. a Theideal Yoredale Carboniferousdeposits of northernEngland were cyclothem is shown in Figure 4. deposited was characterised by structurally Inthis districtthe Lower Liddesdale Group and contrastedareas (Figure 3). DuringCarboniferous lowest part of theUpper Liddesdale Group times thearea lay withinthe tropical belt. Areas consist predominantly of limestone indicating that of relatively rapidsubmergence formed ‘troughs’ non marine influences were comparatively weak at or ‘basins’ between ‘blocks’ or ‘massifs’ which thistime. Rhythmicsedimentation within an subsidedmuch more slowly. Markedly different essentiallylimestone environment is recordedin stratigraphicalsequences, both in thickness and the observed upward sequence of calcareous shale, lithological composition, were deposited in each of darkgrey limestone and light grey orwhite theseareas. Theboundaries between‘troughs’ limestone withinthe Asbian.Ramsbottom (1973) and ‘basins’ werecomparatively narrow hinge ascribedthis cyclicity toworldwide (eustatic) zones alongcontemporary fault lines. In northern changes of sea level. In hismodel, marine Englandbroada ‘trough’, theNorthumberland transgressionswere marked by marine bioclastic Trough,extended from the area ofthe present limestones;regressions byalgal, dolomitic and Solway across the whole ofNorthumberland and fine-grained limestones,shales and sandstones.In into the area now occupied by the North Sea. An some emergenceareas is indicated area of relativelybuoyant rocks formed a ‘block’ by non-sequences,minor unconformities and local area, the Manx-Cumbrian-Alston thearea, Ridge, brecciabeds. Ramsbottom (1977, p 282) grouped extending fromthe Isle of Man across theLake these rhythmic units or cyclothems into a series of Districtand into the present northern Pennines, major cycles or mesothems (each of which may be withfurther ‘troughs’ thetosouth thein recognized by a distincitve fossil assemblage). Stainmore Craven and Lowerareas. Carboniferoussedimentation started earlier in the Deltaicadvances were more pronounced in the ‘troughs’ thanon the ‘blocks’, thoughthese too UpperLiddesdale Groupwith limestones weresubmerged by Asbiantimes. A land mass becomingrelatively subordinate. Elements of the lay to thenorth of theNorthumberland Trough, classicial Yoredale cyclothems of the Pennines (eg in a positionina now occupied by theSouthern Dunham1950, Johnson 1960, Ramsbottom 1973) Uplands. From this, abundant,though may be recognized. intermittent,supplies of terrigenoussediment AppliedGeological Mapping of Dearham and Gilcrux I I

Limestone Where free of superficial deposits most of the limestonesgive rise to distinctivelandscape Because of its ease of application in the field and features.The Fourth and Fifth limestonesin in examinationin of handspecimens Dunham’s particulartypically form terraced hillsideswith (1962) classification of carbonate rocks is adopted low limestone crags alternating with grass covered in this report. slack featuresmarking the outcrop of thethin Wackestones were described by Dunham (1962) as interbedded mudstones,siltstones and sandstones. limestonesconsisting largely of calcitemud with Swallow holes arecommon both on drift-free morethan 10% of therock composed of grains, outcropsand in areas where limestone is present commonly shell or other calcareous organic debris, beneath drift or athin cover of solid rocks. The supportedby the mud matrix. The limestones of thin soils of the limestoneoutcrops supporta this districtare almostall wackestones in which characteristic limestone grassland flora. crinoid fragments occur in a fine grained medium Mudstoneand siltstone to darkgrey calcite mud matrix. Shell fragments are also found but are less abundant. Thin beds of mediumgrey, commonly calcareous mudstone,up to 0.lm thickare locally Packstones of Dunham’s classification are interbeddedwith somelimestones. Bentonitic limestonesconsiderablewith a calcite mud characteristicshave been noted in some of the componentwhichin butgrainsthe are Asbian shales of West Cumbria (Walkden, personal sufficientlynumerous to be incontact with one communicationinMitchell et al. 1978, gl75). another.The fabric of the rockis thengrain Thesehave been interpreted as theproducts of supported.None of thelimestones of thepresent accumulatedair-borne volcanic dustwhich district contain sufficient coarse clastic material to becameweathered to soils duringperiods of warrentthe use of this termexcept perhaps very emergence. No investigation of the clay locally where very small concentrations of coral or mineralogy geochemistryor of any of the shell debris occur. district’smudstones has been carriedout during Mudstones in Dunham’s nomenclatureare thepresent investigation. However the basalts of limestonescomposed of lime mud in which less theCockermouth Lavas, of presumedArundian than 10% of therock consists of grains.Included age,beneath theSeventh Limestone indicate hereare the fine-grained limestones described in volcanic activitywhich couldhave continued previous accounts as porcellanous. nearbyin Asbiantimes. Bentonitic clays may therefore bepresent in some of the mudstones Many beds of nodular limestone are present in the interbedded with the limestones. district.The nodules are almost certainly primary features of thesediment and thussuch rocks are Thicker mudstones are present between individual probablybestconsidered as grainstonesin limestonesthough thisin districtthey are Dunham’s classification. generallypoorly exposed, normally forming slack featuresbetween limestoneterraces. Where seen Most of the limestones are slightly bituminous and the mudstones vary from medium to dark grey in smellslightly ‘oily’ whenhammered. They are colour andare commonlycalcareous. Some are commonlythickly bedded rocks withindividual silty and pass imperceptibly into siltstone. beds up to over 1 m. Thin beds of calcareous mudstone upto 0.1 mthick are locally common Sandstone betweenthick limestone beds. Stylolitic surfaces arecommon. Most limestones arewell-jointed. Fine to medium-grained sandstone occurs between Nodularlimestones areconspicuous by their most of the limestones.In the Asbian and lowest rubbly texture especially in weathered faces. Brigantian, sandstones are subordinate in thickness to limestones. In the upper part of the Brigantian Most of thelimestones haveexperienced slight theyare thicker, with the sandstones between the recrystallisationthough organic remains are Second, Thirdand Fourth Limestones locally generally still easily recognisable. comprising the bulk of the sequence. Most of the Fossils arecommon and are usually most easily sandstones arefine tomedium-grained very pale seenon weathered surfaces. Most common are brownrocks, though coarse-grained sandstones crinoidfragments, brachiopods and large colonial are present in places. Some are characterised by a corals. Bryozoa also occurand some limestones hard siliceouscement and may be regarded as are rich in foraminifera. ganister.Traces of cross-bedding may beseen in some exposures. COCKERMOUTH GILCRUX CALDBECK PENNINE ESCARPMENT (from Eastwood et a/ 1968) (after Eastwood et a/ 1968 (from Eastwood et a/ 1968) (after Dunham 1948) modified by present re-survey)

FIVE YARD

SCAR

SINGLE POST

Chert Beds ------Junceurn Beds TYNE BOTTOM w -- - __ - -

------I

Rough Beds JEW

LOWER LITTLE

t 2o SMIDDY t 30 ROUGH t 40 t 50

...... Sandstone :*. .-**::..:.::

Undivided I100 Metres -Coal

Figure ? Correlation of Fourth Limestone of the district with the Cockermouth, Caldbeck and northern Pennine successions AppliedGeological Mapping of Dearhamand Gilcrux 13

Chert muchdistrict Within the Fifth of the Limestone consists of thickly-bedded massive grey limestone Finegrained silica in the form of chertoccurs as though beds of nodular limestone also occur, and Ovoid to especiallynear alternate theywherewith top, the acrossin the lowest few metres of theFourth massive beds. Limestone onthe south side of MootaHill [1488 3561 and 1477 35731. Beds overlyingthe Fifth Limestone,estimated to be up to 14 m thick, comprise mainly mudstone. Coal Upper Liddesdale Group Thin coals up to 0.2 mthick were noted within Fourth Limestone and overlying beds Following the Fourth Limestone by et al' (1968)* practicethe of previous workers,notably These areno longer exposed and nonewere seen Eastwood et al. (1968) the term Fourth Limestone during the resurvey. has beenretained forthe 130 m or so of strata, composedpredominantly of limestone,which Stratigraphy overliethe Fifth Limestone and mudstone. A The stratigraphical classificationadopted here for generalisedsuccession forthe Fourth Limestone the Lower Carboniferous has been outlined above of thedistrict is givenin Figure 6. From this it (see Figures5 to 7). Descriptionswhich follow is clear that limestone is themain lithology and in Appendix 1 are based both on observations thoughinterbedded units of sandstoneand made duringthe resurvey and thosegiven by mudstoneare important and thin coals havebeen Eastwood et al. 1968 some of whichhave been notedlocally inthe upper part of the sequence. revised inthe light of morerecent work. Faunal Both thicklybedded massive limestones and lists given here have been obtained from existing markedlynodular limestones are common. Up to publications with minor revisions. 40 m of sandstone, with a few metres of shale at the base locally,overlie theFourth Limestone. Lower Liddesdale Group Mediumto coarse-grained gritty sandstones are Sixth Limestone and overlying beds In its western present north of Wardhall Common [I40 3731: fine andnorthern outcrops on the Cockermauth Sheet grained siliceous ganister is present near Millstone thisdivision varies in thickness from 24 to 37 m Moor [135 3601. (Eastwood et a1 1968, p 155). Only theupper TheFourth Limestone succession of thepresent 20 m crop out in the area described in this report. district is intermediate between the west Cumbria Limestone,assigned to the Sixth Limestone, is sequence which is composed almost exclusively of exposed in a quarryat Parsonby [1453 38261 limestone andthe Caldbeck and Pennine areas thoughmuch of themapped outcrop is here where characteristicwhere rhythmic "Yoredale" concealedbeneath boulder clay.Mapping cyclothems are well developed. A correlation indicates the presence of Sixth Limestone beneath withthese otherareas is givenin Figure 7. More boulderclay in the extreme south of thearea, details of theFourth Limestone sequence and its south of Moota Hill [around 143 3511. correlationwith other districts are discussed in Inthe singleexposure of thislimestone in this Appendix 1. TheFourth Limestone forms awide areathe rock is compact a dark grey rock. outcropin the east andsouth of thedistrict. Elsewhere inthe Cockermouth area Eastwood Naturalexposures are common andthere are et al. (1968) recordwhite limestone in the upper numerousabandoned quarries both thein part with some beds of shale and in places a thin limestonemembers and locally in the interbedded coal seam. The limestone is overlain, in this area, sandstones. Quarryingcontinues today thein by thin shales and sandstones (see Appendix 1). Fourth Limestone at Moota Quarry [ 146 3631. ThirdLimestone and overlying beds TheThird Fifth Limestone and overlying beds This limestone Limestone is up to 10 mthick. It forms narrow is estimatedto be some 40 mthick. The Fifth Limestone forms wideoutcrops in the extreme outcropsin the east and south of thearea but is east andsouth east ofthe district. Although generallypoorly exposed. It is typicallya dark muchcovered byboulder clay sections are greylimestone withabundant scattered crinoid exposed in abandonedquarries atHigh Close debris.In most places it may be classified as a [1461 38091 andnear Parsonby Brow [1433 3833, wackestonethough in a few samples thecrinoid 1464 3745 and 1416 38091. fragmentsare sufficiently abundant to meritthe term packstone. 14 AppliedGeological Mapping of Dearham and Gilcrux

Inferred position of Gastrioceras subcrenatum Marine Band

0Undivided

I50 Metres

Figure 8 Generalized vertical section of Namurian AppliedGeological Mapping of Dearhamand Gilcrux 15

Up to 50 m of beds overlie the Third Limestone. Dinantiantothe almost exclusively freshwater Thesewere collectively referred to theOrebank deltaic environments of the Westphalian. Sandstone by Eastwood et al. (1968, p 159). The basal member of theHensingham Group Althoughlittle detail is known abouttheir known as the Mensingham Grit hasbeen composition inthe present district it is clearthat interpreted asa near-coast deposit (Ramsbottom shales locallycomprise an important part of this 1978, p 179). sequence. thisInreport theterm Orebank Sandstone is preferredonly for the well-marked TheHensingham Group is verypoorly exposed sandstone which overlies the limestone. not only in the district but throughout its outcrop in west Cumbriaand relatively few boreholes Second Limestone andoverlying beds This have penetrated it. It is thus the least well known Limestone,which is upto 8 m thick, forms very part of theCarboniferous sequence.However the narrowboulder clay-covered outcrops in several limitedamount of dataavailable suggest that the of the fault blockssouth of theGilcrux Fault. It group is subject to considerablevariations in comprisesmainly grey limestone with scattered thickness.Smith (1921) recordsat least 488 m of crinoiddebris. Exposures are few exceptin the beds assignedto theHensingham Groupin the south of the district. Bank End and Blue Dial boreholes [0512 3845 and 0724 40671. In neither borehole was the base of UPPER CARBONIFEROUS NAMURIAN - theGroup proved. At Crosby the Hensingham Classification Group has thinned to approximatley 158 m and at Aspatria,immediately north of thedistrict a The Namurian sequence of the district is shown in similarthickness is recorded.Eastwood (1939) Figure 8. Detaileddescriptions of thesequence attributesthis thinning to the development of an presentwithin the district are given in Appendix east-north-east trending anticlinal ridge soon after 2. The lowest formation is theFirst Limestone thedeposition of theFirst Limestone.Eastwood which was includedwith the Chief Limestone et al. (1968,p81) suggest thatthere is clear Group inprevious classifications (eg Eastwood evidence forthe progressivethickening of the et al. 1968 andBarnes et al. 1985). Thestrata Hensingham Group northwardsa into abovethe First Limestone up to theinferred position of the Gastrioceras subcrenatum Marine southwesterlyextension of theNorthumberland Band are known as the Hensingham Group with a Trough as advocated by Trotter and Hollingworth ( 1927). thicksandstone unit, the Hensingham Grit, at the base. Limestone Conditions of deposition and sedimentology Thedetails of limestonelithologies thein Dinantianapplyequally here.FirstThe The broadregional structuralframework of Limestone is generallymedium greya ‘troughs’ and ‘blocks’ establishedinDinantian times persistedinto Namurian.the The thickly-beddedwackestone with scattered crinoid alternation of marinelimestone deposition with and shell debris. increasingly important influxes of deltaic sediment Sandstone established inthe latter part of theDinantian continuedNamurian.theinto The basal The best exposed and hence the most well known formationof the Namurian, the First Limestone, sandstone in the sequence is the Hensingham Grit. marksthe last significantperiod of marine This is typicallya coarse- to very coarse-grained limestone formation. theAbove in this, thicklybedded massive sandstonein which HensinghamGroup, clasticsediments are kaolinised feldspargrains are common. Pellets of dominantas deltaic influences assumed increasing earthyhematite or hematite-rich shale up to 2cm importance.Occasional periodsmarine of across arepresent locally. Fine-grained, rather influencearerepresented by thinbeds of flaggy,sandstones occur higher inthe Namurian limestone or mudstone which yield a characteristic sequence. fauna.Theestablishement, albeit relatively briefly, of such marine conditions affected a very Mudstone widearea. Themarine beds so depositedare Darkgrey mudstones, locally with brachiopods therefore of greatvalue for regionalcorrelation. TheNamurian strata represent a transition from crop out near Gilcrux. Clayironstone nodules are thepredominantly marine conditions of the presentsomein of the mudstones. Silty Bivalve Lithostratigraphical Stages Zones Groups

UPPER Secondary -0 YESTPHALIAN SlMlLlS Reddening C -PULCHRA Widespread - - - -

- 50

IBLACK METAL

FIRECLAY

WH ITE METAL MIDDLE LllTLE COAL LOWER MEASURES SlMlLlS SLATY - PULCH RA -1 00

TEN QUARTERS NESTPHALIAN B

RAlTLE R TOP BANNOCK BOTfOM BANNOCK

-150 METAL METAL STRINGER CANNEL

YARD LOWER YARD

MODIOIARIS Vanderbeckel (Solway) MB* HALF YARD - 200 Metres TWO FOOT

LllTLE MAIN

Coa I

-M-M- Marine Band (MB)

I /:. I NESTPHALIAN :*:::';:':;: LOWER . COAL A . .*..*..*...*.* : .: : . . -.a. . UPPER THREE QUARTERS MEASURES . , ... *.. * :. * :.-. COMMUNIS Inferred position . *..- :::. .*: .*. ' : :e. * LOWER THREE QUARTERS ' **.:. ... . '. .* :: '.'......

LENLCATA ISU HARRINGTONFOOTFOUR

~ ~~ M-M-M-M SubcrenatumMB* NAMURIAN HENSINGHAM GROUP

Figure 9 Generalized vertical section of Westphalian AppliedGeological Mapping of Dearham and Gilcrux 17 mudstoneswith plant fragments have also been outcrops are concealed beneath boulder clay. recorded. The 125 m of bedswhich are estimated to comprise the remainder of the Hensingham Group Stratigraphy are verypoorly known both inthis district and The First Limestone of Cumbria is the equivalent elsewhere inCumbria. Although they occupy of theGreat Limestone of Northumberlandand wideoutcrops south and south west of Gilcrux the northern Pennines and the Main Limestone of they may beseen only in avery few widely theYorkshire Pennines. It belongs thein scattered exposures,. the best of which are in Rose Pendleian Stage (El) of the Namurian. Because so Gill [09 10 37401 and Leathers Gill [ 1250 38001. littledetail is known aboutthe Hensingham Groupsequence it is difficult to suggest reliable UPPER CARBONIFEROUS- WESTPHALIAN correlationswithother areas. However the (COAL MEASURES) limitedevidence available from elsewhere in Classification Cu9bria indicatesthat the Group belongs tothe Pendleian andArnsbergian Stages. The position generalisedA section of the CoalMeasures of thestage boundaries within the succession of (Figure9) is based onthe description of these thepresent district is unknown:and no attempt rocks by Eastwood (1930) and on the revision by has beenmade tosuggest their presence on Taylor (1961). Details of the sequences within the figure 8. In places in Cumbria nuch higher beds, district are given in Appendix 3. The base of the belongingto the Yeadonian Stage yield Coal Measures is drawnat the presumed position Gastriocerascumbriense. considerable A of the base of the Subcrenatum Marine Band, the non-sequence,in which four Namurian stages are preservedsequence withinthe Dearham-Gilcrux absent is thusindicated (Ramsbottom 1978, areaextending some distance above the inferred p 179). It is notknown whether higher beds of position of the Aegiranum Marine Band. Yeadonian age are present in this district. Details of individualformations including Conditions of deposition and sedimentology descriptions of exposures are given in Appendix 2 Fluvialand deltaic sedimentation established in (P 45). thedistrict during the Namurian (p 15) became dominantduring thedeposition of the Coal First Limestone Measures.Although the sea was largelyexcluded, therewere periodic, short-lived but widespread TheFirst Limestone which is up to 15 mthick marineincursions, probably associated with typicallyconsists of mediuma grey, thickly eustaticfluctuations of sea-level. The Coal beddedlimestone. Thin shalypartings along Measuressequence is cyclic,and can be regarded uneven or wavy bedding planes are common. The as being constructed from many individual cycles, wideoutcrops of FirstLimestone inthe faulted eachapproximating to an ideal formin which groundsouth of Gilcruxthe Fault are fossiliferousmudstone is overlain by considerably obscured by a cover of boulder clay. Naturalexposures may beseen on TallentireHill unfossiliferousmudstonessandstones, and [120 3581, Top Wood [133 3621 and Wardhall succeededby a seatearth with a coal seam at the top(Figure 10). Cycles arein reality commonly Common [ 137 3711 andin several abandoned quarries. incompleteand may varylaterally. They may die aut or converselya single cycle may split, giving rise to additional cycles. The Coal Measures Hensingham Group sedimentsare dominantly argillaceous,with the Theterm Hensingham Group is applied to the bulk of thestrata consisting of mudstones,silty whole of theNamurian succession above the top mudstones or very fine-grained sandstones.The of the First Limestone. coarsergrained sandstones arein places pebbly In thisIn districtthe basal member of the andcommonly represent fluvial channel-fills. Hensingham Group is the Hensingham Grit.This The bases of sandstones may therefore rest on the has a maximum thickness of 25 m and forms wide erodedsurfaces of subjacentstrata, and this may outcrops south of Gilcrux. Where seen in the Top account forthe absence of otherwisepersistent coal seams in certain areas. Wood [ 133 3671 and Gilcrux [ 1 173761 areas the Hensingham Grit is typicallycoarse-graineda gritty,rather feldspathic sandstone.Elsewhere its 18 AppliedGeological Mapping of Dearham and Gilcrux

DEPOSITIONAL ROCK TYPES ENVIRONMENTS

COAL 1Swamp SEATEARTH IA * A A I

Alluvial distributory channels Prograding 'delta Delta platform SILTSTONE AND SILTY MUDSTONE Deltaslope I MUDSTONE Fresh to brackish- WITH SHELLS water lagoon DARK GREY Marine shelf MUDSTONE WITH MARINE FOSSILS

Figure 10 Idealized Coal Measures cyclothem

Reddening Stratigraphicalsummary (see Appendix 3 for details) The higher part of the Coal Measures sequence is characterisedin the area, as elsewhere inBritain, Lower Coal Measures by thepresence of redcolouration. Such red This division, about 130 m thick, lies between the stratawereformerly categorised as the inferred position of the Subcrenatum Marine Band Whitehaven Sandstone 'Series', and wereregarded (atthe base) andthe inferred position of the as aformation distinct from, and unconformable Vanderbeckei Marine Band. The strata are mainly upon the 'Productive theupon Coal Measures' mudstonewith thick, but commonly impersistent, (Eastwood 1930). It was subsequentlyshown sandstone beds. (Taylor 1961) thatthe reddening was asecondary effectsuperimposed on the normal grey measures Thereare someten named, and economically and related to intenseoxidation below a important, coalseams ranging from 0.23 m to pre-Permianland surface at timea when the 0.82 m in thickness (see Figure 9). The Lickbank climate was aridand the watertable markedly and Three Quarters seams have been economically depressed. It is notknown to whatextent this the most importantand reserves of thesetwo reddeningoroxidation affects the engineering seams may remain in the area. properties of these rocks, if at all. LowerThe MeasuresCoal are exposed sporadicallyalong the valley of theRiver Ellen Stratigraphy between the Dearham and Mother Pit Faults, and The following account (also see Appendix 3 p 47) also inthe lower part of Row Beck north of is based on thedescriptions by Eastwood (1930) Dearham. and Taylor(1961), with subsequent revision of boreholecorrelations, examination of mine plans Middle Coal Measures and assessment of availableinformation from This division attains a thickness of about 225 m in opencastexploration. With onestated exception theDearham and Gilcrux area, but is incomplete: faunal lists are based on Taylor (1 96 1) and have Triassic strata restunconformably on the eroded not been revised. top. Theupper 65m of theMiddle Coal NY 0624 3500 NY 0841 3788 NY 0819 4000 I Rosegill Pit I

NY 1129 4000 NY 1190 3707 NY 1427 3500

Metres 150 River Ellen

100 EN QUARTERS 50

OD OD

-50 -50 -100 -100 -150 -150

Grouo Horizontal Scale 0 100 St. Bees Shales l : :*I ~~~~s~~,“~us x7. LImestone 1 I cl0 0 El Metres AgMB Aegrranum Marme Band SQ Undtvlded Vertical Scale 2x horizontal VdMB Vanderbeckel Marine Band s lcl L SbMB Gastnoceras Subcrenatum Marine Band

igure 11 Horizontal sections ,1 -“/’ I’ ’ ,L,’ ’ /’ L’--’ u

05

/al Blown Sand Alluvial Fan Raised Beach Deposits Till (Boulder Clay) and Glacial Drift, undifferentiated

Alluvium,(including River Terraces Present Beach Deposits Glacial Sand and Gravel Solid rock at surface El and Lacustrine Alluvium) Scale 0 1 2 3 4

Figure 18 Quaternary deposits AppliedGeological Mapping of Dearhamand Gilcrux 21

Measures is secondarilyreddened below the sedimentation now thesite of theIrish Sea. The unconformity and is of little economic value. overlying St Bees Sandstonemarks an influx of coarsersediment laid down on alluvial plains The strata are mainly mudstones with interbedded traversed by large braided rivers. sandstoneswhich aregenerally impersistent. Near Dearham there are exposures along the Row Beck Stratigraphy and also in its tributary Garley Gill. In the valley of theRiver Ellen strata of theMiddle Coal majorThestratigraphical subdivisions are Measures are exposed in a northbank tributary summarised below. Moredetailed descriptions of between theMother Pitand Rosegill faults. the sequence in the district are given in Appendix Upstream from the Rosegill Fault reddened strata 4. high inthe division are visible inriverside exposures. St Bees Shales Some tennamed seams havebeen worked inthe This formation is notexposed but is known from past the most important of whichhas been the boreholescompriseto some 80 m of red Main Band. This coal hasa tripartitestructure mudstones with a thin breccia at the base. containingthree leaves calledin ascending order theCannel, the Metal Band and the Crow seams St Bees Sandstone with variable thicknesses of intervening measures. Thisformation consistsmainly of fine-grained Each leaf may exceed lmin thicknessand the reddishbrown,laminatedand locally aggregate thickness of the Cannel and Metal Band cross-beddedsandstone. The total thickness of at Dearham is about 2.70m. Recently it has been the StBees Sandstone in the area is about 100 m. worked in the Oughterside Opencast Site [NY 110 Outcrops of thickly-beddedand cross-bedded 4001. sandstoneoccur onthe coast north of Bankend TheTen Quarters Seam has also beenwidely [050 3921 andin disused quarries [0760 39901 workedwithin the district and is of excellent north east of Crosscanonby. quality. STRUCTURE PERMO-TRIASSIC TheCarboniferous rocks of thearea are cut by Classification twoprincipal sets of faults,onetrending north-westwardsandtheother with trends Permo-Triassicrocks are confined to the area varyingbetween east-west east-north-and north-westof the Maryport Fault and comprise eastwards. Theprincipal faults shown on the the StBees Shales and the StBees Sandstone. The geological mapare proved from coal-mining basal mudstoneformation, the St Bees Shales, evidenceto be accompanied by an even greater which is onlyknown from boreholes,rests number of minorfaults parallelto theprincipal unconformablyupon the Coal Measures.In south trends.Members of bothsets of faultstruncate and west Cumbriathe St Bees Shales are foldstructures, although it is possible thatfaults considered to be of Permianage. The higher and foldsdevelopedand simultaneously. The beds, however, may beof Triassic age (Arthurton north-west trending faults throw down both to the et al., 1978). The younger StBees Sandstone, south-westand tothe north-east whereas the which is wholly of Triassicage, occupies the complimentaryset approximately at right angles entire surface outcrop of the Permo-Triassic rocks throwdown mostly, but not exclusively, to the north of the Maryport Fault. north. Conditions of deposition and sedimentology Theneighbourhood of Maryportmarks a transitionbetween an area to the south in. which Towardsthe close of theCarboniferous period faults of north-west trend are dominant (Barnes et extensive deformation tookplace which was al., 1986), andthe Dearham-Gilcrux area in accompaniedand followed by uplift and erosion. which faults of east-north-easttrend assume a Permian and Triassic strata, predominantly red in greaterimportance. Contemporaneous faulting on colour,were laid down in intermontane basins east-north-eastaccompanyingwithlines, whichcoalesced eventually burythe to deformationthein marginal zone may have Carboniferousland surface. The St Bees Shales affectedthe deposition of LowerCarboniferous representsediments laid down in a coastal plain sediments.Subsequent re-activation of such environmentmarginal to anarea marineof 22 AppliedGeological Mapping of Dearham and Gilcrux faultsin late or post Carboniferoustimes may Measureslie in structural basins truncated by the have given rise to the existing fault pattern. MotherPitand Birkby faults, but possibly formerly co-extensive with the synclinal structure There is no directevidence of contemporaneous atDearham. A considerable number of thefaults faulting of Carboniferous age. However Eastwood affectingthe Carbonifeorus rocks are shownon (1930) concludedthat an anticline (or dome) in the geological mapasterminating against the thearea of theCrosby Borehole west of Allerby MaryportFault. It is notknown forcertain how was initiatedfollowing the deposition of the theyrelate to this structure and the fault pattern NamurianFirst Limestone, thus accounting for inthe Carboniferous rocks below the Triassic is theknown variations in the thickness of the unknown. Thefault-zone of theMaryport Fault Mensingham Group between the Crosby areaand hasbeen detectedonly at the end of an inclined theHayborough-Bankend area where the strata cross-cut drivennorth-westwards from Crosby are much thicker. Pit. Thesparse data available suggest thatthe All faults in the Dearham-Gilcrux area are known St Bees Sandstone north of theMaryport Fault to displacevarious horizons within the dips to the north-west at angles up to 20 degrees. Carbonifeorussequence and therefore the latest Thesouth-easterly dips on the north-west flank fault movements are no earlierthan the late of thesynclinal structures adjacent theto Carboniferous. The juxtaposition of the Maryport Fault may wellgive way north-west of secondarily reddened Coal Measures strata against thefault to north-westerly dips assuggested by theHensingham Group alongthe GilcruxFault Eastwood (1930, p. 98). whereit crosses RoseGill, and also along the Mother Bit Fault south of Rose Gill Mill, may be MINERALISATION of significancethisconnection.in As the Vein mineralisation is common particularly in the reddening does notappear to cross these faults it LowerCarboniferous rocks of thedistrict though may be concludedthat final fault movements locally there is also evidence of mineralisation postdate the reddening and are therefore probably adjacenttofaults inthe Coal Measures. The of Permian orlater age. Final movementalong distribution of mineralisation is shownon the the east-north-east trending Maryport Fault which Mineralisationmap. Baryte is the commonest brings Coal Measures against St Bees Sandstone is introducedmineral but copper, zinc and iron clearly no earlierthan mid-Triassic, although minerals are also knownand traces of early orpre-Triassic initiation of movement may hydrocarbonmineralisation have been found. have taken place. Nickel mineralisation within the Coal Measures is All faultsin the area are normal, hading in the likelyto be of diageneticorigin (ie the result of direction of downthrow(Figure 11). Thedip of chemical and mineralogicalchanges withinthe thefault-planes is generallyabout 60 degreesto stratasince theirinitial deposition). Brief 80degrees although shallowerinclinations are descriptions of the district’smineralisation are known.Faults are generallymultiple, a major presented in Appendix 5. fracture beingaccompanied by zone a of subsidiaryfaults, in places extendingseveral Origins of the mineralisation metreson eitherside. The dip of the strata commonlysteepens near a fault,in places With theexception of the smallamounts of becomingnear vertical, as along theDearham sulphidespresent in clay ironstone nodules in the Fault. Coal Measures, the mineralisation in the district is clearly epigenetic (ie it post dates the host rocks). Inthe ground south of theGilcrux Fault the There is no evidence within the district to fix the Carboniferous strata dip gently westwards towards date of themineralising episode more precisely theneighbourhood of Dearhamwhere there is a than post Carboniferous.However the mineral broadsouth-plunging syncline adjacent tothe assemblages closely resemblethose in many other largeDearham Fault, which throws down over deposits in and around the northern fringes of the 200 mto the east. West ofthis fault dips in the LakeDistrict such as those of PottsGill and Hensingham Groupandtheoverlying Coal Ruthwaite.The mineralisation of thepresent Measuresswing roundtowards the south-west. districtthusis likely formto part of this TheGilcrux Fault and its western offshoots have province. In recenta genetic classification of a generaldownthrow to the north of LakeDistrict mineralisation Stanley and Vaughan approximately 400 m. Between thisimportant (1982) proposed a late Carboniferous (Stephanian) dislocation andthe Maryport Fault the Coal to Permian date for this episode. Contours indicate level in metres above Ordnance Datum. The contours shown relate only to natural rockhead surface. Solid rock at surface

Scale Area of worked-out opencast 0I 1I 2 3 4 I kilometres Figure 13 Rockhead elevation / /’ ‘. ::..::, ,.::::.:_’ / 0

/

lsopachytes at 10 metre intervals

The contours shown relate only to drift deposits and do not take Into account made ground SoI id rock at surface Scale 0 1 2 3 4 I I I I Area of worked-out opencast kilometres

Figure 14 Drift thickness AppliedGeological Mapping of Deahm and Gilcrux 25

It has alreadybeen mentioned (p 21 above)that Rockhead thedistrict lies astridean E-W belt of major Rockheadelevations areshown in Figure 13 and faulting.Faults within this may havebeen active drift thicknesses inFigure 14. Although fort. duringCarboniferous sedimentation forming a much of thedistrict there is only a limited hingeline separating anarea of shallowwater amount of borehole informationit appears that depositionto thesouth from arelatively deeper therockhead surface broadly reflects the present basinal environmentto the north. The district topography though, in common with other similar thus has importantsimilarities to such areas as glaciatedlowlands, this surface may locally Navanand Silvermines inIreland (eg Hitzman & exhibita somewhat greater relief. Drift cover is Large 1986, Phillips & Sevastopulo 1986 and generally less than 15 mover much of the area Russell 1986) wheremajor stratiform lead-zinc thoughareas with up to 30 m or more of drift depositsoccur in LowerCarboniferous limestone havebeen identified,for example to the east of host rocks adjacent to faults which may have been Dearhamand thein Ellen Valley north of activeduring sedimentaiton. Mineralisation seen Oughterside Mill. On thehigher ground of the atoutcrop in the present district could be an district, east of Gilcrux and Tallentire, drift cover expression of muchmore extensive mineralisation is generally less than 5 m with large areas clear of atdepth, perhaps remobilised andintroduced to drift deposits.On some of thelimestone outcrops thepresent structural level during very late small areas of bare limestone occur. Carboniferous or Permian times. The modern Ellen valley appears to be essentially Resources coincidentpre-glacialwith a valley though Thedistrict and adjoining areascould merit betweenOughterside Mill [ 11 IQ 39081 and systematicinvestigation, initially by geophysical Ellenhall Bridge [ 1 165 39071 the present day river andgeochemical methods, to investigate further course has clearlybeen deflected slightly to the the possibilities of base metaldeposits atdepth. south of itsformer course.Downstream from The widespread occurrence of baryte in limestone Bullgill [096 3841 post glacial erosion has remsved wallrocksencourages search for economic superficial deposits from the valley sides for muck concentrations of themineral inthis part of of course.its Upstream from Bullgill the Cumbria. pre-glacial valley is infilledwith glacial deposits to depths of over 30 m locally and there is limited QUATERNARY evidence to suggest a local deepening of the solid floor of the valley hereabouts, Quaternarydeposits include sediments of glacial and post-glacialorigin (Figure 12). Glacial Quaternary deposits depositsconsist mainly of boulderclay or till which was laiddown by ice sheets of Devensian Boulder clay agewhich invadedthe area during the last Boulderclay mantles much of thedistrict. Over 100 000 years. The tillmantles much of the parts of the western half of the district its surface district, together with smaller areas of glacial sand exhibits well developed low ellipticaldrumlin and gravel. The most widespreadpost-glacial ridgeswith a general NE-SW alignmentwhich in deposit is alluvium,belts of which flank long part reflects the trend of ridges in the underlying stretches of theRiver Ellen and several minor rockheadsurface. Elsewhere, for example QII the streams. Small areas of river terrace deposits have Hensingham Groupoutcrop north of Tallentire beenmapped in places inthe Ellenvalley and andon the hillslopes south of Gilcrux,the smallalluvial fanshave also beenrecognised. boulderclay surface is typically feataareIess. Along thecoast present day beach deposits are There are few good naturalexposures of boulder succeeded inland by belts of raised beach deposits. clay though large sections are occasionally exposed Other post glacial drift depositswhich occupy in the workings of the Oughterside Opencast Coal very small areasinclude lacustrine alluvium and Site [ 110 3951. Fromthe limited evidence calcareous tufa. available theboulder clay of thedistrict appears Only inthe valleys of afew streams inthe west to be lodgementa till, that is tilldeposited of thedistrict and on thehigher ground in the beneath a glacier, which consists mainly of sandy, east has erosionremoved thesuperficial deposits stonyclay. Most commonlythe boulder clay is to revealsolid rocks. However it is unlikelythat greyto brownish grey in colousthough in. gla~~s a significant thickness of drift was ever deposited inthe north of thedistrict, where the St Bees on some of this eastern higher ground. Sandstone reddenedor Coal Measures have 26 AppliedGeological Mapping of Dearham and Gilcrux

contributedsignificantly toits composition, it 1.0 m of silty,gravelly sand. Sandy and gravelly assumes adistinctly red or reddish brown colour. soil may be seen in the arable fields further to the Includederratics are characteristically rounded to west. sub-rounded anpd commonlyshowstriated surfaces. Alluvial Fan deposits Bouldersup to 2’:m across havebeen noted but Alluvial Fan deposits have been mapped at several most are below 0.75 min diameter. Common pointswhere tributarystreams join the main rock types include a variety of Lake District rocks valley. Incomposition these deposits are similar .amongstwhich several distinctive lithologies have to the alluvium:they are distinguished principally beenrecognised. These include Carrock Fell theironsurface morphology. No precise Gabbro,chiastolite hornfels, granophyre and thicknessescan be given forthe fan deposits granitethe Carrock Granophyre and Skiddaw withinthe district thoughthey are unlikely to Graniteand numerous boulders of porphyritic exceed 3-4 m. ‘Eycott type’ basalt.Clearly many of theerratics havebeen derivedfrom thenorthern Lake Lacustrine alluvium District.A few boulders of Criffelgranodiorite Lacustrinealluvium hasbeen distinguished in the from SW Scotland have beennoted. These flat-lyingground immediatelysouth Stof become morenumerous towards the west of the Cuthbert’s Church, Arkleby [ 1415 39201. Where districtand are dominant in the ground west of seen inditches on theedge of thedeposit it the Riverthe Ellen.Limestone andsandstone consists of darkbrown generallystoneless silt. ,bouldersare also common in theboulder clay Up to1.5 m of thissilt were seen atone point thoughthese give no specificindication of [1414 39021 though the maximum thickness of the provenance. deposit is unknown.It is howeverunlikely to exceed 2-3 m. Glacial sand and gravel Glacialsand and graveloccurs locally assmall Marine and Estuarine Alluvium and associated peat outlyingpatches on the boulder clay surface to deposits the north of the River Ellen. At least 3m of sand Extensive deposits of alluvium are situated in the and gravel are exposed -in disused a pit areas of low groundon the landward side of [0940 38531 north west of Bullgill. Ingeneral coastal drumlinsthegroundin west and however the thickness is less than this. north-west of Crosscanonby[065 3921. These Alluviumoccupies an almostcontinuous belt of predominantlynon-marine accumulations are flatground flanking the River Ellen along most composite andcontain the stratigraphical record of itscourse throughthe district. Small sections of a marineincursion into the area at a time of through these sediments at numerouspoints along formerhigh sealevel. Afterthe last glaciation theriver banks show up to 1.0m of darkbrown the land was progressively drownedduring the silt. Trial bores for the diverted minor road north eustaticrise of the sea from itsglacial low level. east of EllenhallBridge [ 1 165 39071 provide As the sea rose it induced a rise of water table in detailsthrough themargin of thealluvium. Here theadjacent low ground,thus initiating peat thealluvium consists of up to 2.1 m of siltyclay growth,but progressively drowningpeat on the above silty sands and gravels which may be up to rise of the sea to stillhigher levels. Eventually 1.8 mthick overlying boulder clay. Thin alluvial theinter-drumlin hollows at Crosscanonbywere depositsoccur numerousin stream valleys floodedby the sea and the deposition here of throughout the area. organicclays was succeeded by thedeposition of siltyclay with marine diatoms. According to River terrace deposits Huddartand others (in Kidson and Tooley 1977) the sea had access between 6810 years and 6495 Riverterrace deposits are restricted to asmall years before present, after which the sea level fell number of placesalong theEllen valley. East of as post-glaciationland uplift began to exceedthe Bullgill terracedeposits have been mapped on rate of eustatic sea levelrise, andorganic clays bothsides of theriver where they form began to accumulate again. The top of the marine bench-likefeatures whichreach up to 3 to 4m deposits,at 4.44 mabove OD is well below the abovethe level of thealluvium. Therather presentsurface of thealluvium at 5.50 above degradedsides of therailway cutting east of the OD. site of Bullgill Station [lo37 38911 showabout AppliedGeological Mapping of Dearhamand Gilcrux 27

Peat aregroundwater natural degree in of solubility collectivelyknown by theGerman term ‘karst’. Peat,with thetree stumps in position of growth, Within theeastern part of thedistrict the Lower whichaccumulated on the site of thepresent Carboniferous outcrop, which consists mainly of a intertidal zone as the sea rose towardsits highest thicksequence of limestonesexhibits certain level, now emerges frombeneath covera of typicallykarst features.These features were modern beach deposits west of Crosscanonby [053 initiatedduring interglacial periods of the 3921. This‘submerged forest’, of unknown Quaternarywhen availability and movement of thickness butprobably less than a metre thick, is groundwater was at a maximum. currently exposed over a wider area than has been previously recorded on this coast. Most conspicuous of theseare numerous swallow holes or dolines. Theirdistribution is shownon Raised beach deposits the Swallow Holes map.Eastwood et al. (1968, p.156) comments on theconcentration of swallow Onthe seaward side of the coastal drumlinsat holes atabout the top of theRough Limestone, Crosscanonbyprominent raised cliff-lines have which formsthe basal member of theFourth been cut by thesea as it stood at a former high Limestone. Within thepresent district no such level. Beach deposits,including the sand and concentration has beenobserved and swallow shingledeposits of stormbeaches, are banked up holes are developed at almostall stratigraphical against these old cliffs at levels up to 7.5 m above levels withinthe limestonesequence. Theyare OD. This is substantiallyhigher than the highest however rathermore numerous in the lowerpart level to whichcontemporaneous clays were wheretheproportion of limestone thein depositedon the tidal mudflats in the sheltered succession is greatest.Although most occur now areas protected by the drumlins. onoutcrops of barelimestone, fewa swallow holes penetratea metre or so of other lithologies Blown Sand of theoverlying beds and several penetrate the Elongateareas of blown sand,quarried in places, thincover of boulderclay which commonly occuralong theinner margin of the raisedbeach overlies the limestone surface. Most swallow west andnorth-west of Crosscanonby. holes theindistrict areroughly conical formin andare up to 30 macross attheir widestpoint. Calcareous tufa generallyare They lessareand depththan in 5 m usually flooredwith collapsed boulder clay or Calcareous tufa is currently being deposited in the othersuperficial material. Ina few instances for lowercourses of several of theun-named left exampleon Wardhall Common [1358 37321 and at banktributaries of LeathersGill Beck, north of Millstone Moor [ 1359 36241 the floors are wet and Gilcrux. In the northernmost of these [ 117 1 38601 boggy andafter prolongedrain tend to hold. a pale browncellular crusts of tufaup to 0.3m shallow depth of water. thickcoat moss, twigs and boulders andform extensiveterraces inthe stream bed. In the Swallow holes withbare limestone visible in the easternmost stream [1207 38491 tufafragments base may beseen in theFifth Limestone east of forma gravelbed tothe stream. Hazel nutsand the B5301 road in the extreme east of the district small twigs coatedtufain areparticularly [around 150 3741. Streams may seenbe common here. descending into swallow holes at [ 1214 3604, 1287 3528, 1276 3561 and 1499 37511. The All of thesestreams rise as springs from the un-namedstream draining the south side of Gilcrux Fault. No sign of tufadeposition has MootaHill sinks at variouspoints [eg 1400 35431 been observed around any of the springs and it is along courseits dependingonweather and only in the lower courses of the streams that this groundwaterconditions. In other cases swallow depositiontakingis place. seems It likely holes areapparently unconnected with current therefore,that much of the calciumcarbonate drainage.Little is knownabout the district’s now beingdeposited has been leached by the undergrounddrainage. However no evidence of streams fromthe limestone-rich boulder clay in anyform of cavesystem has beendiscovered in their short upper courses. any of thenumerous quarries in the limestone Karst features outcrop.It is thuslikely that no major cave sys@m is present and that drainage is effected by Geomorphological features characteristic of terrain numerousnarrow channels along and between consistingpredominantly of bedrock witha high jointand bedding planes. The swallow holes of 28 AppliedGeological Mapping of Dearham and Cilcrux Table 2. Former collieries with a take within the district

Collieryname, including Approximate Grid Seam(s) workedDate of abandonment as given individualshaft names' Reference of catalogueinCoal British of m ain mine mines2 main abandoned entrance

Birkby(Albright, Florence 0798 3630 Upper Three Quarters 1938 Florence,Orchard) Orchard 0729 3651 Birkby (Nos 1 & 2)NQ 1. 0750 3741 Lickbank 1949 NQ 2. 0757 3747 Upper Three Quarters 1950 Lower Three Quarters 1949 Albrightsn 1950 Birkby (Mother) 0724 3742 Mother or Little Main unknown Number 1 unknown Number 2 or Lickbank unknown Upper Three Quarters unknown BraytonDomain (Hall) 1299 401 6 Yard unknown BraytonDomain (No 3) 1600 41 52 Yard 1902 BraytonDomain (No 5) 1388 4017 Yasd 1942 Bullgill, (Ash, Broad- Ten Quarters 1910 meadow, Bullclose, Crosby Rattler 1910 Eliza, Ellen, Jane, mainly in square Thirty Inch 1910 Lodge, Ten Quarters) 10 38 Metal 1910 Yard 1910 Little Main 1910 Crosby (Ellen) 0973 3855 Ten Quarters 1898 Rattler 1898 Thirty Inch 1898

Metal 1898 Yard 1898 Little Main 1898 Number 1 1898 Number 2 1898 Crosby & Gilcrux mainly in square Ten Quarters 1888 10 38 Metal 1888 Un-named 1888 Crosby & Rosegill Rosegill No 2 Ten Quarters c 1897 Ellen, Rosegill No 2) 0841 3788 Thirty Inch c 1897 Metal c1897 Yard c 1897

Dearham (Croft, Hope Lonsdale 0694 3573 Ten Quarters 1894 Lonsdale, Lowther, Lowther 0676 3623 Rattler unknown Parkin, William, Wright) Metal 1894 Cannel 1894 Yard 1894 Little Main 1894 Lickbank unknown AppliedGeological Mapping of Dearham and Gilcrux 29 Table 2 (continued).

Collieryname, including Approximate Grid Seam(s) workedDate of abandonment as given individualshaft names' Reference of in British Coal catalogue of main mine mines2 main abandoned entrance

Ellenbank Quarters0617 3758 Three Upper 1952 Three QuartersLower Three 1952 EllenboroughVirgin & Ewanrigg (?) unknown (Cass, Far, Gravel, Ten Quarters unknown Henry, High, Jacob's mainly in squares Rattler unknown Well, John, Lady, Mall, 05 35, 06 35 Me tal unknown Scott, Middle, Rough & 07 35 Cannel unknown Ground, Thompson, Yard unknown Watergate, William) Lady Pit (?) unknown Ellenhall 1173 3855 Metal 1938 Gilcrux (Ashtree Ten Quarters unknown Broadmeadow, Brow, Thirty Inch 1854 Bulls Close, Croft, Me tal 1854 Crooks, Damside, Ellen, mainly in square Yard unknown Eliza, Fretchville, 10 38 Jackson, Jane, Lady, Lord, Mirehouse, Morrison, Sellby, Skelbrow, Smith) Isa 0765 3787 Cannel 1932 Mill (Paitson, Bell) 0755 3590 Crow 1928-9

Qughterside 1131 3990 Ten Quarters 1930-3 Rattler 1930-3 Thirty Inch 1933 Me tal 1933 Yard " 1933 Little Main 1930 Rosegill 0841 3788 Ten Quarters 1897 Rattler 1897 Thirty Inch 1897 Me tal 1897 Yard 1897 Little Main 1897 Townhead 0755 3590 Crow 1903 Westmoor End 1055 3976 Quarters Ten 1939 Rattler 1939 Thirty Inch 1939

1. The namesquoted are those givenin the British Coal catalogue of abandonedmines. Some duplication occurs with certain individual shafts included in one or more groups of plans. 2. Thedates given are those registered in British Coal catalogue of abandoned mines.In certain cases the date may be the date of registration of thtplan rather than the date of abandonment of mining. 30 Applied Geologicsal Mapping of Dearhamand Gilcrux thearea appear to resemble the ‘solution dolines’ Oughteaside Opencast Coal site. of Cramer (1 94 1). Theseare developed by Within the presentdistrict other forms of made pronouncedsurface solution of the bedrock at OF d extent.The disusedHigh around some favourable point such as a joint arry 11 47 3821 is currently intersection. There is no evidence that any of the being infilled with domestic refuse. district’sswallow holes result from collapse into solutionvoids, the ‘collapse dolines’ of Cramer At MoQ~~Baarry [B 46 3621 made ground consists (op.cit.). The disappearanceunderground QF the streamsouth of MQO~~Hill may provide an Backfilled opencast sites are of limited extent and example of the ‘alluviumstream sink doline’ of are confined ts the former Blooming Heather this classification. 6053 351 and 062 3533 site south-west of Dearham Where free of superficial depositsseveral and parts of theOughterside site 6120 400 and limestone formationsform bare craggy QPIL~CTOPS 126 4061 worthof Gilcrux. Atthe former site typicallywith little or no soil cover. No backfilled ground amountsto approximately 20 limestonepavements ~f thetype characteristic of hectares to a maximumdepth of 25 m. At south Cumbria or the Yorkshire Pennines occur in Oughterside theextreme southern portions of thedistrict. However several natural outcrops areas and C amounting to a total of exhibitsolution sculpturing of thetype described approximately 9.5 hectares extend into the district. by Bogli (1960) and this feature has been Maximumthickness of backfillhere amounts to observed on few aolder quarried surfaces, approximately 45 m. indicatingthat this process candevelop within a Opencastexcavations filledarewiththe few decades. overburden which was originally taken from them. Deposition of calcitein the form of tufaaround Where spoil heaps remain from nearby abandoned boulders, twigs and ~QSSoccurs in several streams deep mines, as atOughterside, this material is north of Gilcrux (see above), The calcium used as part sf the fill. carbonate is believed to have beenleached from limestone-rich boulder clay. GROUNDWATER By far the most importantmineral produced in MADE GROUND AND BACKFILLE the district in terms of overall tonnage, value and OPENCAST SITES area of working is coal. Undergroundmining Thesecover only a very small proportion of the ceased someyears ago andworking by opencast district although there are locally some significant techniquesended recently though some reserves areas of collieryspoil. Areas of thismaterial are remainand may be extractedinthe future. presentaround the disused sites of Crosshow Limestone was formerlyan important product of Colliery [069 3663, BirkbyColliery BO77 3751, theeastern part of thedistrict asevidenced by Wosegill Colliery 1085 3801 and Bullgill Colliery numerousabandoned quarries. Production 1098 3851. Thereare numerous small heaps of continuestoday from one quarry and at the time spoilassociated with otherold workings of writing(June 1988) limestone is the district’s throughoutthe Coal Measures outcropbut these sole mineralproduct. Small quantities of are generallymuch too small to be mappable. sandstone have been worked for building stone in Collieryspoil heaps are composed principally of the past butaresumption of working is very shale waste togetherwith minor amounts sf unlikely.Trials have been made on twosmall sandstone.Spontaneous combustion of pyrite-rich veins of barytethough only very small amounts shale has occurred in the spoil tips at Birkby and wereproduced. The widespread occurrence of Bullgill collieriesgiving the remainingspoil its thismineral both in this and adjacent districts characteristic brick-red colour. MQS~of the heaps suggests that some further investigation sf this of collieryspoil withinthis district are relatively type of mineralisationmay be justified. Small inconspicuous featuresin the landscapeand in deposits of sand and gravel have provided a small some cases, egCrosshow Colliery, large areas of local supply inthe past but no worthwhile spoilhave become heavily vegetated. The large reserves remain.knownare to Whereas conical tipat BirkbyColliery howeveris a sediment2ryironstone, fireclay and ganister all prominentlandscape feature. Spoil associated QCCUI- in the district there are no records of these with the former Oughterside Colliery 11 i 42 39901 ever beingworked here and reserves are very has been used restoringin adjacentthe unlikely to attractcommercial interest under AppliedGeological Mapping of Dearhamand Gilcrux 31

foreseeableeconomic conditions. duringlatter the half of nineteenththe firstand half of thetwentieth centuries. During this Some Of good water may be periodlargetonnages weresupplied to the heavy obtainablefrom the LowerCarboniferous industries of west Cumbria, mainly for coke formations of theeastern part of thedistrict making and steamraising. A considerable though mine workings renders proportion of the district’s output was exported thegroundwater of the CoalMeasures unsuitable throughthe formerly large coal handling port of for use. Maryport.Heavy industries were not established inthe present district in contrast to areas further Coal south. Coal remainsthemost important economic Underground coal productionwithin the district mineral of thedistrict. Seamsof economicwent into decline in the 1930s and 1940s and importance occur within a sequence approximately became extinctwith the abandonment of the last 260thick theLowerm in andMiddle Coal colliery, at in 1952. Measures. Themajor production has come from severalprincipal seams, namely the Ten Quarters, The volume of individual blocks of unworked coal Main andLittle Main, which vary in thickness andthe presence of old workingsmake any andquality throughout the district and are not resumption of underground coalmining within economicallyworkable in all places (Table 2). thedistrict veryunlikely under presently Smaller amounts of coal have beenproduced foreseeable economic conditions. locally fromother seams. In places even the Interestin opencast coal productionarose during better seams deterioratein quality or thickness WorldWar I1 andresulted in exploration of a and may becomeunworkable. Shale partingsare number of sites inCumbria. Severalsites within present insome seams notably the Slaty, Ten thedistrict wereprospected but production did Quartersand Metal, and washouts, known locally not startuntil 1964 withthe development of the as ‘nips’ may bepresent in certain seams, for Blooming HeatherSite 3511 SW of Dearham. example the Bottom Bannock. Calcareous [053 Coaling from thissite continueduntil 1969. mineralisationadjacent to faults in several seams inthe Oughterside Opencast site has rendered Opencastextraction at Oughterside [llO 3951 in thenorth of thedistrict ended in July 1988. parts of these seams unworkable. A more Further possibilitiesexist within thedistrict for widespread effect,involving Coal Measures strata opencastextraction and prospecting forfurther abovethe Ten Quarters Seam in the Dearham, Rosegill, Bullgill andOughterside areas, is reserves near Dearham is in progress. secondaryreddening. This feature is theproduct Limestone of intense oxidation prior to the deposition of the Permo-Triassicformations. Not only has theLimestone is the district’ssecond most important process resultedinthe oxidation ofiron minerals mineral productafter coal. Much of the withinthe Coal Measures sediments but in many Dinantian and lowest part of theNamurian cases whole coalseams have beendestroyed by sequence consists of limestone andthere are wide oxidation.Certain seams maytherefore locally be and commonlyrelatively drift-freeoutcrops to the absentwithin thereddened sequence. east of TallentireandGilcrux. These outcrops are The Cumbrian Coalfield has had a long history of scarred by numerousquarries,old though coalproduction. Most seams yielded bituminous limestone extraction is today confined to one large coals of highvolatile contentand with strong quarryat Moota [ 143 3631. Small quarriesare cokingproperties, perhaps best described as present in all of the main limestone formations of ‘general purpose’ coals. Theywere ideallysuited the district and these no doubt formerly supplied to coking,to gas making,steam raising and small local needs for buildingstone and lime. household use. Fewrecent analytical data have The largestexcavations are confined to three of beenpublished though Taylor (1978, pl85) notes the formations; the Namurian First Limestone and theDinantian Fourth and Fifth Limestones. Of that volatile contents of Cumbrian coals calculated ona dry ash-free basis varyfrom 32 to 39 per these byfar the greatest production has come cent. Brief descriptionsof the characteristics of fromtheFourth Limestone andit is this Cumbrian coals weregiven by Jones (1957, pp formation which is today worked at Moota by the 83-4). Bothel Limestoneand Brick Co Ltd.Quarry developmenthere in recent years has advanced The heydayof coal mining in thedistrict was theworkings northwestwards in the upper part of 32 AppliedGeological Mapping of Dearham and Gilcrux theFourth Limestone. This quarry produces certainly from the Hensingham Grit and resemble various grades of crushed raw limestone for use as closely the stone formerly quarried in old shallow roadstoneand concrete aggregate and in addition pits [ 1329 3659 and 1325 36401 on the hill to the sometar-coated roadstone is produced.Finely south of Grange Grassings. Reddened Coal crushedlimestone is also producedand used on Measuressandstones, formerly referred tothe site in the manufacture of lime-silica bricks. Whitehaven Sandstone,have been quarriedon a small scale at several places most notablyGarley Three limestoneunitswithin the Fourth Gill,Dearham [0667 36121 andon the west bank Limestonewere formerly worked on alarge scale of theRiver Ellen I0874 38221 east of Crosby. at the Wardhall group of quarries [centred around According to Eastwood (1930, p125) this stone 138 3821 between Gilcruxand Parsonby. The was much used inbuildings in Dearham village quarrieswere served by an inclinedtramway and in the construction of several railway bridges. whichconveyed stone to aloading bay onthe Other Coal Measuressandstones are generally less Carlisle to Barrow in Furness railway [ 1240 39601. satisfactoryasbuilding stones but material of Some of thelimestone was burnt to produce reasonablequality was quarriedon the west bank quicklimeand the large limekilns may still be of Row Beck [0685 36951 north of Dearham. seen adjacent to the railway.Much of the output Small quantities of stone have been obtained from however was supplied as a flux to the iron works a few pits elsewhere for local use. at Maryport.at According to Eastwood et al. (1968, p 243) the closure of this works led to the Many old cottages inthe district incorporate sills abandonment of quarries.the FifthThe and lintels of dressed St Bees Sandstone, no doubt Limestone was formerly worked forground obtainedmainly from quarries Maryportat limestone,road-metal and fluxat High Close immediately to the west of thedistrict. Within Quarry [1473821 south of Parsonby.This quarry thedistrict the BeesSt Sandstone has been is today used as a domestic refuse tip. quarriedonboth banks of Brunshaw Beck [0760 39901 north-east of Crosscanonby, and in a Largequantities of limestoneundoubtedly remain small working [0896 39321 south of Allerby. in the district. None of theformations within the district is Building Stone likelyprovideto building stone suitable for modernrequirements though small pits will no Building Stone has beenobtained from a number doubt continue to provide stone for the repair of of sourceswithin thedistrict. The numerous dry dry stone walls. stone walls havebeen built mainly of stone obtainedeither from smallquarries specially Sand and gravel opened to supplythe immediate need or from loose ‘clearance’ stones gathered from the adjacent Thedistrict contains no appreciable deposits of fields.Quarried stone for this purpose includes sandand gravel. Theonly deposits to havebeen bothlimestone and sandstone; ‘clearance’ stones worked are in the Bullgill area [0940 38531 though includeweathered blocks fromoutcrops and a thequantity obtained musthave been small. widevariety of glacialerratics. Several of the Reserves are likelytobe too smallto be of district’s older buildings are built of heterogenous commercial interest today. mixtures of locally available stone. Fireclay and shale TheOrebank Sandstone has been worked in two moderate sized quarries to the south of Tallentire Several shales and seatearths within the Cumbrian Hill [1210 3550 and 1200 35301. No information Coal Measureshavebeen used thefor has been discovered about the date of working or manufacture of buildingsbricks, refractory the type of product or quantity produced but the productsand sanitary ware. Suitable clays and size of theworkings suggests that they fulfilled shales may existwithin the district. However rather more thanthe immediate local demand. apart from smallscale brick making for local use The Hensingham Grit has beenworked in several inthe past there are no records of the extensive pits south of Gilcrux [ 1170 37551 which may have working of suchproducts. If suitablematerial supplied some of the stone used in cottages in the could be identified,brick clay andrefractory village. Blocks of coarse-grainedsandstone with clays couldperhaps be obtainedas a by-product pellets of hematiteand coatings of barytein the of opencast coal mining. walls of an old building [ 1418 391 51 immediately south of St Cuthbert’s Church, Arkleby are almost Many Coal Measuresshales contain appreciable AppliedGeological Mapping of Dearhamand Gilcrux 33 quantities of pyriteand marcasite.Oxidation of Thereare unlikely to be sufficient reserves of theseminerals is anexothermic reactionwhich in siliceous sandstone withinthe district to attract the presence of carbonaceousmatter in the shales commercial interest. may result inspontaneous combustion.This is a common feature of collieryspoil heaps. The Ironore product of this process is a red brick-like shale in Nodules of impure siderite or 'clay ironstone'are whichsignificant quantities of sulphatessuch as common in many of the CoalMeasures gypsum and residual unaltered iron sulphides may mudstones. Such ironstonescontain up to 25% be present. Such "red shale" may provide a useful metallic iron(Cantrill 1920, p98) and have been fillmaterial for roughtracks or as a sub-base or workedelsewhere thein Cumbrian ~~dfield. hard core infoundation work.Care must be There is however no record of exploitation in the taken to establishthe content of sulphatesor presentdistrict and future economicinterest is residualsulphides if this is to be used with most unlikely. concrete.The spoiltips of Birkby and Bullgill Collieries [0775 3759 and 0980 38521 contain Small amounts of goethiteand hematite, which appreciable quantities of this material. Shale from occur with other vein minerals on Tallentire Mill, thelatter source has been used forfill inrecent are of no economic interest. years. Barytes* Ganister Baryteshas been workedon a small scale from Siliceous sandstoneor ganister has been worked two narrow fault-veins in the Hensingham Group forrefractory purposes from boththe Coal at Rosegill, west of Gilcrux. Brief descriptions of Measures and Hensingham Group in neighbouring the Gilcrux workingswere given by Wilson et al. districts.Although ganister sandstones are present (1922, pp 27-28). The westernvein formerly inthe district none has beenworked except for exposed in Rosegill [0912 374 13 was up to 8.6 B rn local use as rough building stone. wide over a strike length of a few metres only. A trialbelow stream level to adepth of5.5 m Afine-grained, rather sugary textured, white showed good barytebutflooding prevented siliceoussandstone within theFourth Limestone furtherexploration. The eastern veinshowed ;a on Moota Hill has been quarried [1434 36031 for similar width of baryte in an 8.8 m deep trial pit wallingstone. Hardfine-grained palebrown on the north side of Greengill but again work was siliceoussandstone underlies the Third Limestone stopped by flooding.Attempts to locate the vein at MillstoneMoor and hasbeen dug for walling by means of shallow shafts on the south side of stonein small pits NW and NE of thefarm thestream were unsuccessful. Inboth veins, [1339 3595, 1387 3667 and 1395 36591. Sandstone, baryte is the only mineral present and varies from of ganister type, was formerly exposed at two white to pale pink.The precise date of these localities[065 354 and 062 3581 withinthe operations is unknownbut was probablylate last Hensingham Group, south west of Dearham. century. Wilson et al. (loc. cit.)report a total Veryhard fine-grained pale brownsiliceous production of only 25 tons of barytes product. sandstone occurs near the base of the Lower Coal Measureseast of Arklebyand may be seen in Barytemineralisation is widespreadthroughout spoil excavated from Flatts Beck [ 1445 39231 and theLower Carboniferous rocks of thedistrict. as abundant soilbrash east of Arkleby Hall Details of individual occurrences and a discussion [ 1460 39731. of significancethe of this otherand mineralisationare given on p 50. Noworkable depositshave been identified.However, the wide distribution of themineral, when considered in thecontext of theregional geology suggeststhat *Inthis account barytes andbaryte are used in thepresent district and adjoining areas of Lower the sense of Dunham & Wilson (1985). Baryte is Carboniferousfurthermeritmayrocks thepure mineral: barytes is thecommercial investigation for this mineral. product which is, of course, not necessarilythe pure mineral. 34 AppliedGeological Mapping of Dearham and Gilcrux

Non-ferrous metalliferous mineralisation GEOLOGICAL IMPLICATIONS FOR LAND USE PLANNING Minoramounts of coppermineralisation and the occurrence of small quantities of zincand nickel Ground conditions mineralsare described on p 51.No workable Individualgeological formationsanddeposits deposits of thesemetals are known in the district possess certainfeatures which should be noris it likely thatany willbe foundat present consideredplanning in executionand of levels of exposure.However there are grounds engineering projects. for considering this part of Cumbria as a potential targetarea for explorationfor deposits of Irish The characteristics of the deposits of the adjacent type as discussed on p 25. district (Sheets NY02NW,03NW, SW, NX92NE andpart of93SE, Barnes, et al. 1986) is equally Groundwater applicableto much of the present district and is repeated here with modifications. Themain centres of popdationare served with mainswater fromsources outside the district. Itmust be stressed thatthe comments presented Several farms on the Lower Carbonifeorus outcrop hereare for general guidance only and should in have theirown private supplies from springs. noway beregarded as substitutingfor on site The outcrop ofthe Gilcrux Fault is marked by a investigation.Appropriate investigationsite prominent line of strong springs, several of which proceeduresare recommended aspart of the may seenbe rising Gilcruxin village [eg planningprocess for allcivil engineering or 1149 3806, 1159 3810 and 1174 38151. Much of building projects. thiswater discharges into the natural surface 1. Made Ground may pose problems because of its drainage. A trout farm to the north of the village unconsolidatednature,variability its of is suppliedfrom one of thesesprings. Nothing is compositionand, in places,because it may knownabout the quality of water but one of the containsulphur, sulphates and/or methane springs [ 1212 38271 east of the village, and known generatingmaterial. Consolidation of made locally as "Tommy Tack", is said to be saline. The ground may presentsettlement problems. In rate of flow of thesesprings has notbeen other places forexample, where the made determined but appears to be constant throughout ground is variable in nature or on the edges of the year.the Othersprings rise fromthe made ground, differential settlement may occur north-north-westtrending ScuskeldFault. The strongestand most prominent is theScuskeld 2. Alluvium and LacustrineAlluvium. Where it Spring [ 109136571. Severalsprings rise fromthe comprisessand and/or gravel, alluvium will base oflimestone units. Sink holes markthe pose fewengineering difficulties, but beds of outcrops of manyparts of the Dinantian strata. peat, silt or soft clay if present will compact or Surfacestreams flow into several of these,for shearif loaded. Alluvium is upto 5 mthick example at [1288 3527, 1274 3560 and 1500 37521, inthe Ellen valley. In the small valleys it is though most of the sink holes in the district have proportionally thinner. no contributing streams. Aspects of sink holes are 3. Raised Beach Deposits consistmostly of sand discussed further on p 38. andgravel andprovide generally good Incommon with other formerly extensive coal foundation conditions. miningareas,largesupplies of potable 4. Till or boulderclay mantlesmuch of the groundwaterareunlikely obtainable.beto district.In its unweathered state it is astiff Widespreadold workings lower the quality of the over-consolidatedlodgement Typicaltill. groundwater and disturb the naturalgroundwater thedisturb and undrainedshear strengths are inthe range hydrogeologicalregime. Water issuing from old 100-350 kn/m2.It is a good foundation workings is generallyheavily charged with ferric materialwhich presents fewproblems in salts. Within thecoalfield the considerable cover trenching,excavation.tunnellingand of boulder clay effectively limits the potential for However, erratic boulders of hard rocks within naturalrecharge. Additional supplies of thetill areunpredictable in size and location groundwatermay be obtainablefrom the Lower and may causeproblems in site investigation Carboniferous outcrop though the limited demand boring,piling, excavation andtunnelling. in the district gives little impetus to investigation. Individualboulders up to 1.5 macross have been noted locally. Applied Geological Mapping of Dearhamand Gilcrux 35

Theuppermost 1 to 2 m of the till is containedin Building Research Establishment commonlyweathered to areddish-brown and Digest No 250 (1983). Evenwhen covered by yellow stonyclay, which possesses different a substantial thickness of drift, the topmost 1 - geotechnicalproperties, and is inherently 3 metres of mudstone are generally weathered. weaker than the fresh material. If disturbed or Trenching is relatively easy buttunnelling at moistened duringsite investigation or depths of 12 mor less presentssubstantial development,this uppermost till will have its support problems.Mudstone when exposed to shearstrength rapidly reduced, becoming soft waterexpands and isliable toheave. The and plastic. Careshould also be takenat mudstones and siltstonesgenerally pose few contactsbetween till and sandwhere a spring problems inexcavations by normalripping lineoften develops and resultsin local methods. weakening of the clays. 7. Sandstones. Excavation and tunnellin 5. Glacial sand and gravel generally provide good sandstonespresent fewsupport problems but foundationconditions and, where dryor generallyrequires explosives for depths below confined,cansupport considerable loads. 2 - 3 m. Some of thecoarser-grained Problems may be encountered in these deposits sandstones aregritty and highlyabrasive and if they arewater-bearing. In these conditions some sandstones are silicacemented and excavation in sand and gravel may be extremelytough. Ganister, variety a of especially difficult.Oversteepening of slopes sandstoneseatearth found beneath some coals, mayproduce slipping particularly if a spring is a particularly tough rock. line is present at the base of thedeposit. Silt, Joint bounded masses that have been weakened peat and organic clays which may be present as by subsidenceover old coal workings may lenses within the sand and gravel can also give requiresupport indeep excavations and the rise to foundation problemsparticularly those presence of deepopen joints may necessitate related to compactionrelated to differentialand special precautions. settlement. 8. Seatearths mudstones probablyare the 6. Mudstones and siltstones. Reference has commonestlithology immediately underlyimg alreadybeen made (p 11) to the possible coalseams though locally they may occur presence of bentoniticclays within the Lower unaccompaniedby a coal. Theyare strikingly Carboniferous ofWest Cumbria. Such clays differentfrom the sandstone seatearths or cangive rise to ground instability due to low ganistersnoted above and typicallyconsist of shearstrength in both excavations andover readily-weatheredclay minerals, which with naturalor man-made cavities. There is also a abundantrandom internal polished ("listric") potential for swelling or heavein excavations. surfaces,makethem unstable both in Particular attention should therefore be paid to excavations andunder load.Disseminated the physicalproperties of clay beds withinthe pyrite may also be present and comments made LowerCarboniferous sequence whendesigning aboveconcerning theweathering of this foundationsparticularly those suspected of containing bentonitic material. mineral apply here too. 9. Limestone. Excavationtunnellingand in Mudstoneand siltstone together comprise a limestonepresent few problems but the largeproportion of the Coal Measures presence of joints may requirethe installation lithologies. Their clayminerals are stable but of support.Strong inflows of water may be disseminated pyrite is commonly present, rapid encounteredinsome situations. Inaddition weathering of whichleads to groundwater of high acidity (pHx4). The presence of abundant severallimestones contain thinclay or marl partings,commonly less than 0.1 thick, sulphateions in theweathered mudstones, m whichmay cause bedding plane slip where togetherwith such soluble secondary sulphate exposed in excavations.Many of the massive, mineralsepsomiteas (MgS04.7H20)and poorly- bedded limestones are particularly hard gypsum (CaS04.2H20)must consideredbe whenplacing concrete as aqueous solutions of and may require the use of explosivesin large ordeep excavations. Solutioncavities may be sulphatesare known toattack concrete. A useful discussion of the nature of this problem encountered locally. andrecommendations for thetype of concrete to be used wheresuch attack is likely is 36 AppliedGeological Mapping of Dearhamand Gilcrux

Mining deposited with the Mines Record Office the plans commonlyshowed only themaximum extent of One of the purposes of land use planning is to coal extractionand information was rarelygiven ensure, far possible, thatpotential mineral so as on levels or geological observations. In some cases deposits arenotknowlingly sterilised by an different versions of aplan of onemine show alternative and possibly less economic use of that different positions for the extent of workings and land. in some cases the positions of access shafts.The Thereare no known largedeposits of sufficient positions of many shafts,adits and bellpits is economic importancein the district to warrant unknownor at bestvery unreliably recorded. widespreadrestriction of development.However Untilcomparatively recent times shafts were if planningconsent is sought forfuture inadequatelysealed. Most commonlythey were developmentrestrictive a covenant may be cappedator near surface often with timber. considered applicable in certain areas to allow thc These shafts may remainopen below what may working of mineralsany that prior to now be a very unstable surface covering. development.Inthis district the most likely Particulardifficulties associated with pillar and minerals to whichthis may apply are coal and stall workings include: limestone.This procedure would, inthe case of coal, have theadded advantage of locatingany 1. BJp to 60°h of the coalmay remain in situ. As shallowworkings or access shaftsand adits aresult site investigations may fail to identify therebyenhancing foundation prospects without suchmined areas as only a proportion of trial the additionalthe cost of boreholes for site bores are likely topenetrate the oldworked investigation. areas. 2. Packing of theworked areas was notalways 1. CoalMiniitg. necessary,nor was it alwayspracticed. Where Although there is no direct evidence it is probable roof measures have subsided into such an open thatmining of severalseams from near outcrop void to rest on the seatearth or seam floor only andin areas of thindrift began inthis district slight disturbance of thestrata may be beforethe 18th century. It is likely thatthe apparent.The only evidence present in a earliestsuch workings were small adits into a boreholecore may thereforebe little a valley side, usually at or near the seam crop, and fragmentary coal orcoal dust on slightlya bell pits,which were generally less than 12 m weathered and possibly rather rusty seatearth. deepand from which the area of coal extraction was about 20 mwide. Later,deeper seams were 3. Collapse of pillars commonly results in cavities extracted by the pillar and stall methodwith andbreccia zones or ‘pipes’ inthe overlying extractionrates of up to 50%. Panel working was strata caused by upwardpropagation of the probablyintroduced into somepits early in the mined void. 19th centuryand resulted in anincrease in the 4. Competent roof measures, for example proportion of extraction.This method sometimes sandstone, may resistcollapse for considerable involvedreworking or ‘robbing’ earlier pillar and periods. When roof failureoccurs it may take stallworkings. The longwalltechnique later place in a suddenand unpredictable pattern replaced these earlier methods and resulted in the and timescale. highestratio of coalrecovery. This was the methodemployed finalthe in years of Areas of longwall extractiongenerally may be underground mining. assumedtopresent less cause for concernat surface for the following reasons: It is clearly importantfor the planner, developer or civil-engineertoappreciate the extent of 1. Themethod was usuallyrestricted to deeper individual seam outcrops and the various methods seams. of coalextraction practised in the past, each of 2. Longwall extraction was morerecent in its whichcarried its own potential problems. One of applicationand the workings were usually the commonest and most serious hazards presented accurately surveyed and documented. by old workings is that prior to 1900 few reliable documentaryrecords were kept and of those 3. Althoughsubsidence may be substantial and whichdo exist, feware likely to be accurate. willbe proportional to the thickness of coal Althoughin 1872 became ita statutory extractedit is generallyassumed to be largely requirement abandonmentfor plansbeto contemporaneous with working and is expected AppliedGeological Mapping of Dearhamand Gilcrux 37

to be completewithin few years a of predictable. extraction. Evidence for shallowmining not recorded on Coal productionin the district came fromabout plans is derived from such surface features as old 10 principalseams though other seams were shafts or bellpits and collapsedground. Ancient, important locally. All undergroundmining came unrecordedworkings may occur at shallow depth to anend in the early 1950s. A large area of the inany area where acoal thick enough to be Coal Measures outcrop has beenundermined by worked lies nearthe surface. The possibility sf workings inat least one seam andin someareas shallowworkings near the outcrop of coal seams severalseams have been worked. Most of the mustalways be borneinmind inboth the extractionmethods outlined above have been planningconstructionand phases of any employed. developmentandappropriate sitein . shouldbe carried out. Mine shafts are Oldshallow mine workings can have major both the geologicalmap and the bo implications forthe surface stability (Healy & shaftsite map. The sites of all shafts known to Head 1984). Workings atany depth can cause BGS and British Coal havebeen plotted, but subsidence at the ground surface but the thickness others may exist. of themined seam, the nature and condition of theoverlying strata and the type of workingsall BarytesMining. Small scaleworkings for barytes have aninfluence on theheight to which voids are known in the Rosegill and Greengill areas (see can migrate and the effects at the ground surface. p 50). The depositsoccur here as vertical veins up to 0.61 mwide in faults. Several shaftsup to Severalgeneral "rules" have been used to indicate 12.8 m deepwere sunk. The extent of workings the depth above which the majority of subsidence is unknownbut was certainly small and is likely eventswhich affect the surface are initiated. tohave been confined to driveages no more than However, some of these may be of local use only 1m wide across the vein,probably asmountin andexceptions to almost all havebeen noted. It a maximuma of 100 malong each vein. is necessary thereforeto adopt anapproximate stoping is known to have taken place. Small voids "rule"which can be usedbyplanners and may remainin these old workingsbut they are developers so thatpotential instability can be unlikelyto present significanta hazar reasonablytaken into account prior to the development is considered intheir i development of the land. neighbourhood. In this study the commonly accepted basis that 10 timesthe seam thickness represents the maximum Other features to be considered in height of collapsethrough typical Coal Measures 1. Landslips have been mapped on the north side strata (Piggott et al. 1977) has beenadopted. of theRiver Ellen at [0780 37831 The slips However,users of theresults should always be haveoccurred in BoulderClay at ~o~~~~~~~ aware that there will be exceptions to this "rule". where the valleyslopesbeenhavewherethe In the Cumbrian Coalfield the maximum thickness oversteepened and the banks undercut by river of a worked coal seam is about 4 m but the usual erosion. Thepresence of sandand gravel thicknessvaries between 0.5 m and 3 m. Thusin lenses withinthe BoulderClay, which covers this area 30 m is taken as an appropriate depth to most of the valleyslopes, may promote the coal seams above which particular attention should infiltration of groundwater leading to softening be paidto thepotential for groundsubsidence. and weakeningof theclay mass and localised Areas of knownor potential coal extractionat a zones of increasedpressures.pore depth of less than 30 m below ground level are Oversteepeningand undercutting of the lower indicatedon the shallow coal workings map (in slopesby rivererosion, which effectively pocket). stresses the slopes by removal of support, may lead to mass movements in the form shallow The areasdelineated are generalised andin of consideringparticular sites It is essentialto translationaland/or rotational landslips.Care should be taken not to undercut further the consultthe original documents (held by British toe Coal) fromwhichinformation has been of the bank or load the top in slipped areas, or inother locationswhere similar geological abstracted. Workings knownfrom mine plans conditionsexist,this as (held by British Coal) can be anticipatedand may re-activate existingslips ortrigger new takeninto account when planning, but areas of ones, unless probableor possible workingaremuch less appropriateremedial measures are taken. 38 AppliedGeological Mappiizg of Dearham and Gilcrux

Where constructionactivities are proposed, a 5. Wastedisposal and groundcontamination. The siteinvestigation and subsequent appropriate suitability of oldexcavations in the district for stability analysis should be carried out to assess disposal of waste is limited.As most of the theeffect of theconstruction work on the excavations arepermeablein formations, for stability of the slope. example limestone or sandstone, the type of waste materialmust be carefully monitored to ensure 2. Swallowholes. Swallow holes are numerous on thatthe leachate doesnot contaminate nearby the exposed limestone outcrops and in addition streamsgroundwater.or Similarly percolation several are known to penetrate a few metres of intothe underlying formations must be slow theoverlying solid strata or drift. Sites of enoughensureto natural detoxification and individualswallow holes andareas in which adequate dilution. theyare particularly numerous are shown on theaccompanying swallow hole map. Other At the time of writing (June 1988) the only active swallow holes may be presentbeneath drift waste disposal site is High Close Quarry [ 146 3811 deposits andtheir detection is oftendifficult. in the Fifth Limestone, which is being filled with Nolarge voids or caves are knownin the domestic refuse. limestones of thedistrict. However their possible presence andthat of drift-covered swallow holes shouldbe borne in mindwhen planningconstruction work in limestone country. 3. Flooding. The villages of this district are sited well above river levels andflooding is nota major problem. The largestriver, the Ellen, evenduring the wettest periods of the year, now has regulateda flow so most surface run-off is discharged without flooding the flat alluvial tracts along its course. Where minor flooding does occur in the district itis caused by artificialdisturbance of the naturaldrainage. Examples are present around some pit tips and railway embankments.

4. Seismicity. The only known records of seismic activity originating within the district are those of two very minor earthquakes with epicentres inthe Maryport area; they may havebeen a result of collapse of old mine workings, though the possibilityconnection aof withthe MaryportFault or arelated major fracture is notinconceivable. Theeffects of larger earthquakeshave also beenfelt inthe district (Musson 1987). The Carlisle earthquake of 26 December 1979 causedminor damage at Dearham(Musson, Neilson and Burton 1984). This is notjustification for regarding the district asexceptional and prone to seismic activitybut here, as elsewhere in the country, thepossibility of seismic events of unusual intensitydoes exist and should be taken into considerationdesigningwhen sensitive structures. Applied GeologicalMapping of Dearham and Gilcrux 39

CONCLUSIONS AND RECOMMENDATIONS 1. Extensivecoal mining in the past now places 8. Thedistrict contains resources of coalwhich restraintsplanningon development, or could be worked by opencast methods. especially in areas where coal has been mined at shallow depth.Subsidence associated with 9. The district contains resources of limestone. the collapse of oldworkings will be greatest 10. Resources of sand and gravel are restricted to overareas of shallowancient pillar and stall a small areanear Crosscanonby though the workings,some of which may be unrecorded. amounts present are very limited. The possiblepresence of unrecordedshallow workings should be taken into account before 11. Sandstoneand limestone have been quarried any development is contemplated in such areas locally forbuilding stone. Large scale working as thosenear theoutcrop of coalseams and forbuilding stone isunlikely in the future since appropriatesiteinvestigation carried out. most of the rocks are unlikely to meet present day There are numerous shafts, many of which are specifications. However they could be worked for poorlydocumented. Many shafts are likely to low quality aggregate or constructional fill. havebeen left untreated, orinadequately 12. Thepresent district acd adjoining areas may treated after abandonment. beworth investigating for economicdeposits of 2. Subsidencefrom deep minesis likely to be barytesand research of the area’s potentialfor completebut local settlement may stillbe buried base metal deposits should be considered. anticipated. 13. Widespreadold mining inthe coalfield areas 3. Particularattention should be paid tothe has disturbedthe natural hydrogeological regime physicalproperties of clayand mudstone loweredand quality the of groundwater. formationsLowerespeciallythe in Significantquantities of potablegroundwater are carboniferous where certain beds may exhibit unlikely to be obtained from these areas although bentoniticcharacteristics. These may require additionalsupplies may beavailable from the thatspecial consideration is giventothe Lower Carboniferous outcrop. assessment of excavationsandfoundation 14. Thepotential for wastedisposal oldin conditions. excavations is limited as most of these excavations 4. Thegroundwater chemistry of all mudstones areinpermeable formations. Careful selection andsiltstones should be establishedwhere and monitoring is required to ensure that leachate significantsulphate content may require from waste materials does not contaminate nearby particular precautions regarding concrete type. streams and groundwater. 5. The tillwhich covers much of thedistrict 15. Theresults of thisstudy give a basis for generally provides good foundation conditions. assessing ingeneral terms parts of thearea in Slopes indrift may fail if overloadedor whichsignificant mineral resources might be over-steepenedor if the clay mass becomes sterilised by othertypes of development.This locally weakened. couldgive opportunities for options such as avoidance of development,or extraction prior to 6. Madeground, particularly that filling old development, to be properly examined. quarries, poses problems of unevensettlement and of differentialsettlement for structures straddling the boundary of any backfilled site. There are a few backfilled opencast coal sites butthe positions and former depths of these are well documented. 7. Numerous swallow holes occur in areas of the Dinantianand Namurian limestone outcrop. These may beconcealed beneath superficial deposits.Their possiblepresence should be takeninto account before anydevelopment is contemplatedin these areas and appropriate site investigatins should be carried out. 80 AppliedGeological Mapping of Dearhamand Gilcrux

REFERENCES EDMQNDS,C. 1922. TheCarboniferous Limestone Series of west Cumberland. Geological ARTHURTON, R S, BURGESS, I C and Magazine. Vo1.59, pp74-83 & 117-31. HOLLIDAY, D W. 1978. Permian and Triassic in The geology of the Lake District (Ed. Moseley, GARWOOD, E J. 1913. TheLower F). Yorkshire Geological Society Occassional Carboniferous succession in the north-west of Publication, No. 3, pp 189-2GS. England. Quarterly Journal of the Geological Society of London. pp 449-586. BARNES,R P, YOUNG, B, FROST, DV and LAND,D H. 1986. Thegeology of Workington GEORGE, T N, JOHNSON, G A L, and Maryport.Brita'sh Geologicgll Survey Technical MITCHELL, ha, PRENTICE,J E, Report No WA/88/3. RAMSBOTTOM, W H C, SEVASTOPULO, G D and WILSON, R B. 1976. A correlation of BOGLI, A. 1960. Kalklosungand Dinantian rocks in the British Isles. Special Report Karrenbildung. Zeitschri t fiir Geomorpholgie, f No. 7 Geological Society of London, 87 pp. Supplemenband, Vsl. 2, pp 4-21. HEALEY, P W and HEAD, J M. 1984. CANTRILL,T C. in STRAHAN, A, GIBSON, Construction over abaudoned mine workings. W, SHERLOCK, R L.and DEWEY, H. 1920. CIRIA. Pre-Carboniferous and Carboniferous bedded iron-ores of England and Wales. Memoirs of the HITZMAN, M W andLARGE, D. 1986. A Geological Survey: Special Reports on the Mineral review and classification of the Irish Resources of Great Britain. carbonate-hosted base metal deposits in Geology and genesis sf mineral deposits in Ireland. (Ed. CRAMER, H. 1941. DieSystematik der Andrew, C J, Crowe, R W A, Finlay, S, Pennell, Karstdolinen. Neues Jahrbuk f iir Mineralogie, W M and Pyne, J F) Irish Association for Geologie iind Palaeontologie, Vol. 85, pp 293-382. Economic Geology, pp 217-238. DAY,J B W. 1970. Geology of thecountry HUDDART, P, TOQLEY, M J and CARTER, around Bewcastle. Memoir of the Geological P A. 1977. Thecoasts of north westEngland in Survey of Great Britain. The Quaternary history of the Irish Sea (Ed. DUNHAM, K C. 1948. The geology of the Kidston, C and Tooley, M J), Liverpool, Seal NorthernPennine Orefield, Vol.l. Tyne to House Press, pp 1 19- 154. Stainmore. Memoir of the Geological Survey of JOHNSON, G AL. 1960. Palaeogeography of Great Britain. the northern Pennines and part of north eastern DUNHAM, K C. 1950. LowerCarboniferous England during the deposition of Carboniferous sedimentation in the northern Pennines (England). cyclotkemic deposits. Report of the 21st Report of the 18th International Geological International Geological Congress, Norden, Part Congress. London, Part IV, pp 46-63. XI1 pp 118-28. DUNHAM, K C and WILSON, A.A. The geology JONES, J H. 1957. Reporton the Cumberland of the Northern Pennine Orefield. Vol.11, Coalfield in BAYSH, G H J and WATSON, E M. Stainmore to Craven. Economic Memoir British Cumberland, with special reference to west Geological Survey. Sheets 40, 41, 50 etc. Cumberland Development Area: A survey of industrialfacilities. CumberlandDevelopment DUNHAM,R T. 1962.Classification of Council Ltd & West Cumberland Industrial carbonate rocks according to depositional texture. Development Co. Ltd. In Classification of carbonate rocks (Ed. Ham, W E). Memoir of the American Association of MITCHELL, M, TAYLOR, B J and Petroleum Geologists, Vol. 1. Tulsa. pp 108- 121. RAMSBOTTOM, W H C. 1978. Carboniferous in The geology of the Lake District (Ed. Moseley, EASTWOOD, T. 1930. The geology of the E). Yorkshire Geological Society Occasional Maryport district. Memoir of the Geological Publication No. 3, pp 168-188. Survey of Great Britain. MOSELEY, E;. 1978. An introductory review in EASTWOOD, T, HOLLINGWORTH, S E, ROSE, The geology of the Lake District (Ed. Moseley, W C C and TROTTER, F M. 1968. Geology of F.). Yorkshire Geological Society Occasional the country around Cockermouth and Caldbeck. Publication No. 3) pp 1- 16. Memoir of the Geological Survey of Great Britain. Applied Geological Mapping of Dearhamand Gilcrux 41

MUSSON, R M W. 11987, Seismicity of SMITH, B. 1921. Onborings for coal near southwest Scotland and northwest England: with a Maryport, Cumberland. Summary of Progress of catalogue sf‘ earthquakes within 75 km of the Geological Survey of Great Britain for 1920, Chapelcross. B.G.S, 61sbal Seismology Report. pp 85-91. No. 316. TAYLOR, B J. with Palaeontology by CALVER, MUSSON, R M W, NELSON, G and BURTON, M A. 1961. Thestratigraphy of exploratory B w, 1984. Maeroseis rts Historicalon boreholes in the West Cumberland Coalfield. BritishEarthquakes I: N est Englandand Bulletin of the Geological Survey of Great Britain Southwest Scotland. BGS Global Seismology Unit Number 17, pp 1-74. Report No.207(b). TAYLOR,B J, BURGESS, I C,LAND, D H, n the occurrence of millerite and MILLS, D A C, SMITH, D B and WARREN, P T. associated minerals in the Coal Measures of South 1971. British Regional Geology: Northern Wales. Proceedings of the South Wales Institute of England. HerMajesty’s Stationery Office, Engineers Vsl.44 pp 325-48. London. PHILLIPS, W E A and SEVASTOPULO, G D. TROTTER, F M and HOLLINGWORTH, S E. 1986. The stratigraphic and structural setting of 1927. On the Upper Limestone Group and Irish mineral deposits in Geology and genesis of ‘Millstone Grit’ of north east Cumberland. mineral deposits in Ireland. (Ed. Andrew, C J, Summary of Progress of the Geological Survey of Crowe, R W A, Finlay, S, Benwell, W M and Great Britain for 1926, pp 98-107. Pyne, J F). Irish Association for Economic WILSON, G V, EASTWOOD, T, POCOCK, Geology.pp 1-30. R W, WRAY, D Aand ROBERTSON, T. 1922. PIGGOTT, R J and EYNQN, P. 1977. Ground Barytes and witherite. Special reports on the movements arising from the presence of shallow mineral resources of Great Britain Vol. II. Memoir abandoned mine workings. Proceedings of Geological Survey. Great Britain. eonference large ground movements and ~n YOUNG, B A and NANCARROW, H A. structures. University Wales, Institute of P of 1988A. Millerite from the Cumbrian Coalfield. Science and Tecbalaology. Journal of the Russel Society, Vol. 2, pp 5-8. RAMSBOTTOM, W W C. 1973. Transgressions YOUNG, B and NANCARROW, P H A. 1988B. and regressions in the Dinantian: a new synthesis Rozenite and other sulphate minerals from the of British Dinantian stratigraphy. Proceedings of Cumbrian coalfield. Mineralogical Magazine, Vol. the Yorkshire Geological Society. Vol. 39, pp 52, pp 551-2. 567-607. RAMSBOTTOM, W H G. 1977. Majorcycles of transgression and regression in the Namurian. Proceedings of the Yorkshire Geological Society. Voll. 41, pp 261-91. RUSSELL, M J. 1986. Extensionand convection: a genetic model for the Irish Carboniferous basemetal and barite deposits in Geology and genesis of rniaaeral deposits in Ireland. (Ed. Andrew, C J, Crowe, R W A,Finlay, S, Peaanell, W M and Byna, J E;) Irish Association for Econsmic Geology, pp 545- 554. STANLEY, C J and VAUGMAN, D J. 1982. Copper, lead, zinc and cobaltmineralisation in the English Lake District: classification, conditions of formatian and genesis. Journal of the Geologlsa! Society of .Condon. Vol.139,pp 568-57% 42 AppliedGeological Mapping of Dearham and Gilcrux

APPENDIX 1. Details of Lower Carboniferous Mudstone, pale grey, calcareous, (Dinantian) stratigraphy. abundant irregular limestone nodules approx 1.00 m Thestratigraphical classification adopted here for the Lower Carboniferous has been outlined above. Limestone, medium grey, nodular Descriptionswhich follow are based bothon beds common 4.50 m observationsmade duringthe resurvey and those Limestone,medium grey, thickly given by Eastwood et al. (1968) some of which bedded approx bedded 8.0 have beenrevised in thelight of morerecent m work.Faunal lists given here have been obtained Eastwood et al. (1968, p 163) record Lithostrotion from existing publications and have been revised. junceum, L. [Nevnatophyllum] cf. minimus, L. pauciradiale, Echinoconchus punctatus, Dinantian Gigantoproductus cf. edelburgensis and G. cf. Lower Liddesdale Group latissimus. SixthLimestone andoverlying beds. Only the Theuppermost 5.8 m of theFifth Limestone, upper 20 m of this formation crop out in the east consisting of thicklybedded medium grey of thedistrict at Parsonby and in the extreme limestone, are exposed oldthequarryin south,south of Moota Hill. Much of theoutcrop [1433 38331 theat foot of Parsonby Brow. is concealedbeneath boulder clay butthe Eastwood et al. (1968) described 1.8 m of shales limestone has beenworked in the large but now overlying the limestonethough these are not considerably Overgrown quarryat Barsonby clearly visible today. [1453 38261, whereEastwood recorded the Otherquarries showing up to 5.0 m of medium following section:- grey limestone within the upper part of the Fifth Fifth Limestone: Limestone may be seensouth of Parsonby Brow Limestone, dark grey 2.74 m [eg 1464 3745 and 1477 36841. Sandstone, fine-grained 1.52 m Limestoneconglomerate 0.46 m Up to 14 m of beds,probably mainly mudstone, areinterpreted asoverlying the Fifth Limestone Shale 0.91 m in this district. Sixth Limestone: Limestone,darkgrey 11.89seen m Upper Liddesdale Group Today only the lowest limestone is clearly exposed Fourth Limestoneand overlying beds. Following thoughtraces of theoverlying beds may be seen the practicethe of previousworkers, notably inplaces inthe degraded and overgrown upper Eastwood et al. (1968), termtheFourth parts of the face. Limestonehas been retained for the 130 m or so In theextreme south of thedistrict abed of of strata,composed predominantly of limestone, fine-grainedpale fawn and brown speckled whichoverlie the Fifth Limestoneand mudstone. sandstone overlies the Sixth Limestone. Thesebeds comprise the lowest formation of the UpperLiddesdale Group asrecognised in the Fifth Limestone and overlyingbeds. Theoutcrop presentdistrict. In detail the stratigraphy of the of thislimestone is, likethat of the Sixth FourthLimestone is rather complex. TheFourth Limestone, largely concealed beneath boulder clay. Limestonesequence of theCockermouth area, Its thicknessis thereforedifficult to estimate immediately to the south of the district is a little accuratelythough seems to beup to 40m. The over 50 thickm and is almostexclusively lowest beds were formerly exposed in the top part limestone. Within thisEastwood et al.(op cit) of ParsonbyQuarry (see above)and High Close havedistinguished the individdal units named by Quarry [ 146138091 once provided a good section Edmonds (1922) inthe Fourth Limestone of the throughpart of the formation. This quarry is Egremont-LamplughTracednorth-area. today used asdomestica rubbish dump. The eastwardsacross the present district individual following section was recorded in 1987: limestones and interbedded strata thicken with the Limestone, mediumgrey, thickly incoming of Yoredalecyclical sedimentation. bedded, alternately massive and Figure 7 illustratesthe passage from the nodular beds nodular 3.00 m dominantlylimestone facies of west Cumbriato the typicalYoredale facies of east Cumbriaand the northernthe Pennines. North of Wardhall AppliedGeological Mapping of Dearhamand Gilcrux 43

Common four limestones separated predominantly Mudstone,pale grey, by mudstonesmappable.the areIn fine-grained sandstone lenses 1.30 m* neighbourhood of MootaQuarry [146 3631 these Limestone, pale grey, nodular 0.30 m* interbedded strata are less clear and appear to be thinnerthough a ganister-sandstone is prominent Limestone,medium grey, thickly onthe south side of MootaHill [eg 1434 36031. bedded, some large Productids, Around MillstoneMoor [ 1365 35901 theFourth becoming compact and splintery in Limestone is generallyconcealed beneath boulder lowest 1.0 m 4.00 m* clay and details of the stratigraphy are unknown. Sandstone,pale fawnish grey, Therenumerousare exposures of Fourth fine-grained, wispy bedded 0.10 m Limestonewithin thedistrict. Many quarries Mudstone,dark grey, some haveworked the formation inthe past and fine-grained sandstone laminae 0.15 extractioncontinues today Mootaat Quarry In [146 3631. The lowest fewmetres of the Mudstone, pale fawn, faintly 0.60 m limestoneexposed in small outcrops [ 14883561 laminated and 147735731 on the south side of MootaHill Limestone, pale fawn 0.12 m containfewa chert nodules. Theabandoned eastern quarryat Moota [148 3621 providesthe Limestone, pale grey, nodular 1.50 m seen followingsection throughthe lower part of the *These beds are inaccessible in the quarry face Fourth Limestone: Sections through progressively higher parts of the Limestone,medium grey, massive, FourthLimestone were formerly visiblein the some large Productids 1.30 m extensive abandonedWardhall Quarries. These Limestone,medium grey, thickly are overgrown today and the following records are bedded, locally nodular 1.10 m taken from Eastwood et al. (1968, pp 163-164). Mudstone,dark grey,laminated Eastern quarry [ 139 3821: non-calcareous, appears to die out Limestone,dark, weathers rough 0.90 m to east 0.03 m L imestone, pale grey,Limestone, pale 0.30 m Limestone, pale fawn,compact, brown-skinned, sandy locallyporcellanous, shell and crinoid debris common 2.75 m Limestone,compact, light grey, some dusky patches 0.90 m Mudstone, pale grey and fawn, plastic 0.25 m Limestoneshalenodules in 0.30 m Mudstone,pale grey, abundant Sandstone, fine,grey-blue, with 0.20 m partially rounded limestone brachiopods nodules 1.00 m* Shale and clay, soft, sandy, with Limestone, pale grey, nodular 1.50 m* nodules of pyritous limestone 0.50 m Limestone,medium grey, thickly Sandstone, hard,fine, average 0.20 m bedded, shell debris 1.30 m white Limestone, pale grey, nodular 0.20 m sandywhite,Fireclay, 0.90 m Mudstone, pale grey, laminated 0.10 m Sandstone,shalyblue,pale 0.90 m Limestone, pale grey, nodular 0.30 m* Shale, sandy, pale blue with occasionalbands dark 0.60 m Limestone,medium grey, thickly bedded, some nodular beds 5.30 m Limestones, grey to white, occasionally nodular with abundant Sandstone, dark grey, Saccamminopsis f usinaformis 10.10 m fine-grained, wispy-bedded, coaly streaks 0.06 m Shale, dark 0.20 m Limestone,grey, pseudobreccia 0.60 m seen 44 AppliedGeological Mapping of Dearham and Gibcrux

Fossils recorded from here include Csninia juddi, Coal, top B)QOI- and smutty, better Corweniarugosa, Lonsdaleia duplicsata, E. below Q.15 PIP f lori formis, Nemistium edmondsi, Echinoconchus Fireclay, dark, ~~~~~~~~~~ yellow 0.05 m punctatus, Productus (Gigantoproductus) cfa edelburgeatsis, P. (G.) latissimus,Sgiai f er cf. Shale, dark 0.30 rn duplicostata and S. cf. trigonadis. Limestone, earthy, nodular in Middle Quarry [1393 38031: part, many large Produetids inclkldhg ~~~da~~~~~~~~~~~~-15 to 0.2 Sandstone,thin-bedded 0.98 m rn ti^^^^^^ Shale,grey-black, slightly sandy 0.90 m soft, black 0.60 blackShale, soft, rn 0.05 m Coal, inferior,with sandstone 8.15 rn Limestone, dark, eart .30 m seen floor Fossils recorded from the beds above the upper Not exposed Not 1.20 m coal inelude FasiculophyHlum cf. densum, Limestone, mostly blue-grey, Lithostrotion junceum, Echinocsncus elegms, frequentlynodular andpartin 9.68 m Gigantopdoductus cfs labisslm2ss, Phicochonetes ef. "spotted" buchianus, Pustsalda ~us~uH~s~and ~~i~i~ome~~a michebini. Limestone, pale greyLimestone, pale 0.30 m Thequarry on Parsonby row 6143438281 is The lowest limestone of Middle Quarry section is reported Eastwood et a/. (1968, 163) to almost certainlythe highest bed sf theEastern by p yield Girvanella thoughthe fossil is said to have Quarry. been rare. Doubtful specimens of Girvanella were Saccammiopsis is reportedto be abundant almost also noted in the large quarry [l398 38631 west of throughoutthe sequence. Other fossils recorded Parsonby Farm. No were found at includespecies sf Lithostrotion, Aulophyllum either locality during t f ungites,Avoaia dsvidssni and Echinoconchtss up to 6.11 m of sh ndstones whish elegans. overlie the Fourth Limestone were noted above in Western quarry [1357 38191: thewestern quarry section at Wardhall. Mapping inthe rather poorly exposed ground t~ the west Sandstone, white ts pink, fine to and south of this quarry in ieates that much coarse 2.40 as m 40 m of generallyfine to mediumgrained, and Shales, dark, with thin earthy locallycoarse-grained sandstone, occupy the limestones rich in Lithostrotion interval up to the base sf the Third Limestone. junceum 3.70 rn South of Wardhall, ~(CBUSPMillstone Moor an Limestone,thin-bedded in upper appreciablythinner fine grained silieesw part,many fossils 4.60 FIB sandstoneor ganister separates the Fourth and ThirdLimestones. This sandstoneforms a Shales, dark, with thin pyritous conspicuous line of crags to the north sf Mi%llstsne limestones at top,small Moor Farm [13653615% and has been quarried at ironstonenodules below; many severalplaces [ 134 3594, 1388 3666 and fossils 2.70 rn 1396 36591. Limestone, thin-bedded 1.10 an Third Limestone sand verlying beds. The Third Shale, dark, blue-grey 0.60 m Limestone is up to B rn thick. It is generally poorly exposed though small outcrops may be seen Limestone,compact, pale grey in anin un-named stream at Wardhall Gate with dark spots; nodular and [I296 38321 and in small, and now largely brown-skinned in places 8.30 m obscured quarries near Eweclose 11335 38021. Shales, dark, with earthy thesouth side of TallentireHill the limestone is limestone in middle 1.20 m overlain by the Orebank Sandstonewhich here may be up to 58 thick. This sandstone BIB Limestones,mainly grey, with two m been worked in two uarries el210 35511 and shale bands in upper half 7.60 I%$ AppliedGeological Mapping of Dearhamand Gilcrux 45

1200 35301 wheresomewhat overgrown sections Grit has beenworked in numerous small pits. todayshow a few metres of fine-grainedwhite Almostall are nowdegraded or filledbut sandstone. Inthe northern quarry the sandstone is abundant spoilshows massive coarse-grained overlainby a few metres of sandyand silty rather feldspathic sandstone. At severalpits near mudstone. All the bedsabove theThird Top Wood thesandstone contains impregnations of Limestonewere termed Orebank Sandstone by pink baryte. Eastwood et al. (1968,p 159) thoughthe term is Strata above the HensinghamGrit. Inthe ground preferredin thisaccount only forthe sandstone. northand west of Tallentireexposures of the Tracednorth-eastwards towards Gilcrux these Hensingham Group are almost entirely confined to beds maintain,or slightlyincrease in thickness, theneighbourhood of RoseGill and its tributary butsandstone is largelyreplaced by mudstone. A Greengill Beck. theIngeneral area of the sandstone was formerlyworked in smallpits confluence of thesetwo streams, stratadipping 11318 38001 south of Wardhall Gate, though these westwards at from 10 to 17O, are cut by two faults have now been obliterated. trendingabout north-north-westwards and both SecondLimestone and overlying beds. The second carryingbaryte (p 0). In Rose Gillthe lowest Limestone is up to 8 m thick. The best exposures visiblebed, its top located inthe stream about are on TallentireHill where it has been quarried 100 metresupstream fromthe Greengill Beck near the top [ 1218 357 13. It consists of pale grey confluence, is asandstone which is presumbedto thicklybedded limestone with abundant crinoid somebe distance stratigraphically above the debris. The limestone forms a low but limestonerecorded thefootwallin of the conspicuous bench feature to the south and east of GreengillVein. A sectionupwards from this Top Wood [ 134 3641 and also to theeast of the sandstonebed to strata immediately east of the radiobeacon on Wardhall Common [138 3731. Rose Gill Vein is as follows: Littleis known about the estimated7 m of beds Mudstone, grey with brachiopods in abovethe Second Limestone as theyare rarely lowerat part least 5.50 exposed. Up to 0.5 mof fine to medium-grained m brownsandstone is exposed immediately beneath Limestone,grey with brachiopods c1.80 m the First Limestone in an old quarry [ 1 186 35551 Mudstone, grey Mudstone, c1.00 m on the south west side of Tallentire Hill. Sandstone 0.75 m APPENDIX 2. Details of Upper Carboniferous Mudstone c2.00 (Namurian) stratigraphy. m Sandstone (ganister) with root FirstLimestone. This unit is up to 15 mthick. It markings at markings least 1.50 is well exposed in numerous old quarrieson rn Tallentire Hill [ 120 3581, near Tallentire Hill Farm Thesebeds, notably the limestone and its [ 120 3641 and on Wardhall Common [ 1370 37191. associatedmudstones are also exposedalong the In all of theselocalities it is amedium grey, lower part of Greengill Beck. thickly bedded fossiliferous limestone, locally with Immediatelyto the west of thefault and barytes thin shaly partings along uneven or wavy bedding veins in Rose Gill, Eastwood (1930) recorded planes.Scattered crinoid debris is commonand about 4.65 metres of sandstoneand mudstone brachiopods and corals may be seen in places. overlain by 0.38 m to 0.60 m of dark fossiliferous limestone. Fromthislimestone 37401 Hensingham Group [09%0 Eastwood (op.cit.) listed Aulophyllumfungites Hensingham Grit. Amaximum thickness of about (Flem.) Caninia cf. denticulata, Productus 25 m is estimated for this unit which overlies the costatus, P. cf. longispinus,Pustula punctata, and First Limestone. Thereare no good exposuresin Spirifer sp. (bisculatus group).He estimated that the district but small sections of sandstone may be the strata in the Rosegill-Greengill Beck outcrops seenin old pitssouth of Gilcrux [1167 37631. lay about 100 mbelow the base of the Coal Coarse grittysandstone and flaggy sandstone are Measures. exposedin ratherdisturbed sectionsbeneath Further west, in gully a [0870 37701 boulderclay in the stream [1152 37221 tothe west-south-west of RosegillbedHill a of south west. dark-grey limestone, 0.6 m thick, is considered to Between GrangeGrassings [132 3691 andTop liewithin the Hensingham Group. The strata in Wood [ 132 3631 the wide outcrop of Hensingham thisarea lie between the Mother' Pit and Birkby 46 AppliedGeological Mapping of Dearham and Gilcrux faults,and are thought to be separatedby a matchedin theEllen valley sequence. It is north-north-westwardstrending fault from the possible that the mudstones and limestones in the Coal Measures of the former Birkby Colliery. borehole are stratigraphically higher than any beds exposed in the valley of the Ellen. West of Dearham,strata of theHensingham Group occur in an in occur Group elongated The sum of the Hensingham Group thicknesses in north-north-westwardstrending fault-bounded theHayborough and Birkby Mill boreholes, a outcrop with exposures in the railway cutting east figurein excess of 400 m,provides a reasonable of Birkby Mill and along the valleys of the River minimumthickness forthe group in thisgeneral Ellen, andits tributaries. The strata inthese area. Below the level sf the limestonebeds near localities dip south-westwards at angles from 5 to thetop of thebore, the Birkby Mill sequence is 20'. The lowest bedsexposed, on thesouth bank analternation of mudstoneand sandstone with of theRiver Ellen andimmediately west of the occasional thin coal seams. DearhamFault, consist of m of siltstone,silty 5 North-west of theMaryport Fault, the Bankend mudstone andfine-grained sandstone overlain by Borehole (see Appendix 6) 12 38451 hard (?silica-cemented)hard of fine- to [05 (Smith 1921),proved minimuma thickness of medium-grainedsandstone with intercalations of 51 1 m forthe Hensingham Group. It comprises siltymudstone in its lower part. Higher beds in mainlymudstone and sandstone with a few thin the railwaythe cuttinginclude mudstone and coals, comparablewith the succession at Birkby sandstoneoverlain by acoal about 0.1 5 mthick. Mill. This coal is probably that recorded west of Birkby Mill in the Birkby Mill borehole 1052036951 at a About 4 km ENE of Bankend, the strata between depth of 25 m (see Appendix 6). the base of the CoalMeasures andthe First Limestonecomprise some 150mainly ofm Loose blocks of decalcifiedshelly limestone sandstone andmudstone. It was provedin the recorded by Eastwood(1930) inthe tributary Crosby Borehole [0824 39611, and in a drift north valley north of the borehole site may represent an west of CrosbyColliery [0912 38591 (see 'ironstone' bed,one metre thick at a depth of Appendix 6). TheCrosby Borehole was almost 7.6 m inthe borehole.A similar rock, higher in devoid of limestone above the First Limestone but thesequence was formerly exposed"in a highly theCrosby Drift passed through a number of disturbedcondition" on thenorth bank of the limestone horizons within the Hensingham Group. RiverEllen, south of Ellen Bank. Both occurrencesare associated withmudstones. From It would appear that a distinction can be drawn in the secondlocality [OSOS 36951 Eastwood (op. thedistrict between the Hayborough-Birkby Mill cit.) records: Buxtoniascrabicula, Choenetes Bankend-BlueDial whichthe area,in hardrensis,Productus latissimus, Productus cf. Hensingham Group is of theorder of 500 mt longispinus, cf. Schellwienellacrenistria, thick and the Allerby-Rose Gill-Tallentire area in Sanquinolites striato-lamellosus. Onthesouth which the thickness is little more than 150 m. bank of the riverand incliffs to the west Mudstones, in places with clayironstone nodules, interbeddedsandstones and silty mudstones with andsandstone laminae, are exposed in Leathers ironstoneconcretions areoverlain byseveral Gillbetween theGilcrux Arklebyto road metres of hard,fine to medium-grained, possibly [ 1243 38051 andGrange Grassings [ 1317 37011. silica-cemented, sandstone. Atthe time of theprevious survey Eastwood Aborehole 1058936001 drillednear Hayborough notedbrachiopods in these shales but gave no penetratedasequence mainly of sandstoneand identifications.Inaddition Eastwood noted a mudstonein theupper part of the Hensingham 0.1 m thick "de-calcified limestone with shells" in Group (see Appendix6). Eastwood (1930) LeathersGill [ 1313 37021 thoughthis was not suggesteda correlation of the highestsandstones confirmed during the re-survey. on the south bank of the River Ellen with beds in Asandstone, up to 12 m thick, is exposed in thelower part of the Hayboroughborehole. This LeathersGillsouth of HighFlattFarm correlationwhich includes strata containing the [ 1250 37851 and has beenquarried [ 1249 37661. decalcifiedlimestones described above is The sections are overgrown but both show massive acceptable, but only if there is a smaller thickness coarse and fissile f ine-grained sandstones. of limestonebetween Hayborough andthe valley of the Ellen. A limestone 4 m thick at a depth of Medium-grainedflaggy sandstones, a few metres 135.32 m inthe Hayboroughborehole cannot be beneaththe inferred base of the CoalMeasures, Applied Geological Mapping of Dearham and Gilcrux 47 are exposed in Becky east Of Strata betweera UppertheThree Quarters Seam [148 1 39431. andthe Six Quarters Seam shownortherlya increase in thickness from above 20 at Dovenby APPENDIX 3. Details OB Upper Carboniferous rn Close, south of Dearham to 34 m at Mother Pit in. (Westphalian) stratigraphy. the Crosbyarea. There is an accompanying Lower Coal MeasuresCoal Lower increasein proportion the ofthe sandstone in lower part of thissequence. A mussel band The SubsrenatumMarine Band has notbeen occurs in mudstonesabove the Upper Three recordedwithin the Dearham-Gilcrux district. Its Quarters Seam. Carbonicola andfish scales have position at outcrop shown on the geological map is beenrecorded at this horizon. A 0.23 m coal, thereforeconjectural. The strata between the 7.6 mabove the Upper Three Quarters Seam, is assumedstratigraphical position of themarine present south of Birkby. In the area north ~f the bandand the Albrighton Seam areabout 13 - River Ellen the Six Quarters Seam is 0.65 m thick 18 mthick and include sandstone. In the area west of MotherPit. Inthe shaft section the east of Crosby a 0.45 m coal, which occurs about thickness is 0.53 mseparated by 0.66 m of 9 m below theAlbrighton coals, probably seatearth from a leaf of coal 0.05 m thick below. representsthe Marrington Four-Foot Seam but is Farther eastin theground south-east of Crosby not present further to the south-west. the coal is absentowing washout.to Strata The Albrighton seams withassociated marine between the Six Quarters and Lickbank seams are bands are well-developed inthe Crosby area and mostly sandstone,and about 10-12 m thick. The coal at thislevel has beenextensively worked sandstonecommonly descends through the south of theRiver Ellen from Birkby Colliery. sequenceto formthe roof of the Six Quarters North of theriver the two principal Albrighton Seam, hencethe name Six Quarters Rock, and is seams are each about 0.45 mthick and separated in places associatedwith a washout inthat seam. by 1.68 mof seatearth. The Albrighton Marine However west of Mother Pit a mudstone roof with Band is recordedabove the higher of thesetwo fishremains and non-marine shells is preserved seams. The Templeman'sMarine Band was above the Six Quarters Seam. Atthis horizon, in provedonly 2.10 m above theAlbrighton Marine Crosby No. 6 Bore, Carbonicola cf. cristogulli? Band immediatelyoverlying a 0.20 mcoal. These and C. aff. pseudorobusta wererecorded. marinehorizons have not beendetected in the Midwaybetween the Six Quartersand Lickbank sequence to the north-east and may die out within seams there is a coal, 0.1 8 m thick. the Crosbyarea. The Albrighton Marine Band The Lickbank Seam varies in thickness from has yieldedhas Lingula and Templeman'sMarine 0.45 - o.82 and has been in the Band Lingula and Rectocornuspira. Strata Dearhamarea. Thethickest coal is nearMother betweenthe Albrighton group of seams andthe Pit and Bullgill. Lower Three Quarters Seam areabout 13 - 16 m thick,with mudstone overlain by sandstone. The Between theLickbank and Eighteen Inch seems mudstones carry asubstantial non-marine fauna thestrata, including sandstone, are about 14 m assigned to the lower part of the Communis zone.neighbourhood the thick in of Crosby, A faunal list forthe Crosby are and localities at diminishingsouthwards tom8near Dovenby thishorizon southMaryport of comprises Close and to 10 minaneast-north-easterly Anthraconaia sp., Curvirimula cf. trapeziforma, direction towards Bullgill. Carbonicola bipennis, torus,C. sp. cristagalli, C. The Eighteen Inch Seam is mostly about 0.50 m C . communis,C. and Naiaditesflexuosus. Fish thick.There is a mussel bandin the roof of the scales and ostracods occur at the base. coal. Anexposure, probably of thisseam, was The Lower and Upper Three Quartersseams are discovered duringthis resurvey at the collapsed separated by 15 m of strata, mainly sandstone, in mouth of an old adit [0754 37441 onthe south the westernpart ofthe area near Birkby. The side of theRiver Ellen at the former Birkby thicknessdiminishes, with loss ofsandstone, to Colliery. Thefauna from the coal roof was about 10 msouthwards towards Dearham, and to identified by Mr P J Brand andincludes about12 m towards the north-east. In thearea Anthraconania sp., Anthracosiaregularis, south of Dearhamthe Lower and Upper Three Anthracosphaerium sp., Carbonicola cf. oslancis, Quarters seams are 0.38 m and 0.41 m, increasing Naiadites aff. f lexuosus, N. quadratus/ f lextlosus, north and east to 0.58 m and 0.76 mrespectively Carbonita sp., Grisina arcuata. in the Crosby area. 48 AppliedGeological Mapping of Dearham and Gilcrux

The Little Main Seam, upto 0.65 mthick, is a Stringer occurs near the top of the interval. persistentvaluable and extensively worked coal. Theindividual Metal Band Seam thein From a mussel bandinthe seam roof the Crosby-Bullgill area is up to 1.08 m with partings, following fauna hasbeen recorded: Anthraconaia and amaximum thickness of 1.04 m has been sp., Anthracosia cf. regularis,Carbonicola cf. recordednorth-east of Bullgill. The seam has bipennis, 6eisina arcuata, Carbonita sp. been worked recently in the Oughterside Opencast The strata between the Little Main Seam andthe Site. In theOughterside area theseam is Vanderbeckei (Solway) Marine Band are estimated commonlysplit by 0.27 m of blackmudstone to be about15 m thick and contain two seams whichseparates a top leaf upto 0.34 m from a nearDovenby Close south of Dearham.The bottom leaf upto 0.43 m. The roofhere is lower of these,the Two Foot or Dovenby Brassy typically of dark grey mudstone and the floor of Band varies from 0.69 mto a thickness in excess grey seatearth. of onemetre, but withpartings. The higher The Thirty Inch (Crow) Seam whichconstitutes seam, the Half Yard, is0.28 mthick. Sandstone thetop element of theMain Band, is generallya is prominent throughout this part of the sequence singleseam, upto 0.84 mthick in the Dearham in the Dearham area but dies out towards Bullgill. area, 0.91 nearm Bullgill and 1.10 m at North-eastof Bullgill aseam referredto as the OughtersideColliery and atthe opencast site at TWQFoot is ofuncertain affinities but may be Oughterside. Thereare up to 15 m of strata, equivalenttothe Half yardelsewhere inthe mainlymudstone and sandstone, between the Coalfield. Thirty Inch Seam and the Bannock seams. A coal, 0.1 5 m thick, is present in this intervalat Middle Coal Measures Dearham. The Vanderbeckei (Solway) MarineBand has not The Bottom Bannock Seam, probablyequivalent been recognised in the Dearham-Gilcrux area but to the Breck Band of RosegillPit andthe Jane itsposition is inferred to lie 13 15 m above the - and Ellenpits at Bullgill, attainsa thickness of LittleMain Seam. The strata abovethe presumed 1.02 m inthe Oughterside area. It has been position of themarine band contain a thin seam, worked inthe Oughterside Opencast Sitewhere 0.15 mthick, about 2 mbelow the Yard Seam. the thicknessrarely exceeded 0.25 m and is This is the LowerMetal Seam of theDearham affectedby washouts.A thinunworked coal, the areaand possibly representsthe Lower Yard Top Bannock Seam is present locally between 2 further south. and abovem4 theBottom Bannock. It is The Yard Seam up to 0.86 mthick, has been presumedthat one of thesetwo coals is the extensivelyworked inthe Dearham, Rosegill, correlative of the Bannock Seam of Dearham. Bullgill-Gilcrux and Oughterside areas. The strata Between 3 and 6 m of strata, mainlymudstone between the Yard Seam and the base of the group andsandstone separate the Top Bannock Seam of seams known as the Main Band are about 20 m from the Rattler Seam. thick, and contain two thin coal seams, the lower The Rattler Seam, upto 0.82 mthick, was of theseknown as the LowerMetal north-east of worked inthe Dearham area but in the Rosegill Bullgill. and Bullgill areas is asplit seam of indifferent The Cannel Seam is thelowest element of the quality,which with partings spans up to 1.83 m group of threeseams known as the Main Band. of strata atJane Pit, Bullgill, and asmuch as In theDearham area, where there are extensive 3.65 m atthe nearby Ellen Pit. Thesequence at workings,the Cannel Seam is in close contact EllenPit may, however, include a representative with the secondseam, the MetalBand, which of the Top Bannock Seam. North-east of Bullgill both to the north and the south is separated from the Rattler Seam reaches a maximum thickness of theCannel Seam by severalmetres of strata. The 0.82 m, althoughit is generally alittle thinner aggregate thickness of the Cannel and Metal Band thanthis inthe Oughterside opencast workings. atDearham is about 2.70 m. AtCrosby Pit the Herethe seam is underlain by greymudstone or separateCannel Seam is over 2 mthick with seatearth, with a roof typically of black canneloid partings,diminishing to 0.76m at Bulgill and mudstone. 0.45 m at Oughtersidewhere the seam splits into Thestrata between the Rattler and Ten Quarters two leaves. The Cannel-MetalBand interval seams vary from 14 m at Dearham, diminishing to expandstom9 in the ground north-east of 9 m at Bullgill and to 6 m at Oughterside Colliery. Bullgill wherea thin seam knownas the Metal TheOughterside opencast workings exposed Slaty Seam havebeen exposed. Yellow crusts of medium-greymudstone with regularly spaced copiapitehave been observed locally on the coal bands of clay-ironstonenodules. Fissures in (Young andNancarrow 1988B). About5 to 12 m many of thesenodules contain white kaolinite, of strata, mainlymudstones and sandstones lie pale brownsiderite crystalsand scattered crystals between the Slaty and the succeeding Little Seam. of pyriteand chalcopyrite. One band of nodules The LittleSeam, up to 0.45 m thick at Dearham, contains small clusters of millerite crystals (Young attainsthicknesses of 0.56 mand 0.51 m at Jane and Nancarrow 1988A). Pit, Bullgill, Oughtersideand Colliery The Ten Quarters Seam is one of the most widely respectively. There is no evidencethat this seam workedand better quality seams inthe coalfield. has beenworked. Little more than a metre of Asplit seam withpartings, it attains a thickness strata separate the Little Seam from the overlying of between B .50 and 2.10 min the Dearham and White Metal Seam atCrosby Pit. Elsewhere the Bullgill areas. It has beenworked almost to thickness is greater,reaching about 5 m at Jane outcropfrom Oughterside, Westmoor and Bullgill Pit and up to 12 m farther to the north-east. collieries and has beenextracted at Oughterside The WhiteMetal Seam, 1.05 mthick at Lonsdale OpencastSite where the floor of the coal isof Pit, Dearham diminished to 0.35 m at Crosby Bit. seatearthand there is typically a mudstoneroof. It is0.51 mthick at Oughterside Colliery.It is Inthe western part of the opencastworkings a not reported to have been worked and at Dearham lower leaf up to 0.58 m thick is separated by only was saidto be ‘brassy’, ierich in pyrite. Old 0.05 m of mudstone from an upper leaf which is shafts on the west side of Flatts Beck [I488 39741 about 1.9 mthick. The split increases to 8.0 m were sunk to a coal which may be at the horizon eastwards in theworkings though with the upper of the White Metal. Twothin coals cropout and lowerleaves, retaining more or less their immediately to the east. They may possibly relate originalthicknesses. Spectacular old pillar and tothe horizon of theLittle, White Metal or stallworkings have been exposedin the seam in Fireclay seams. Up to 12 m of strataintervene the Oughtersidethe Opencast Site (see cover between the White Metal and Fireclay seams, and photograph).In places theworked-out ‘stalls’ atDearham there is athin coal8 m above the haveremained open and when entered in the White Metal. course of opencastoperations the coal was found to be encrusted in placeswith creamy-yellow The Fireclay Seam is up to 2.03 mthick, with earthyjarosite, vivid yellow copiapite,white partingsand has beenrecorded at the Lonsdale epsomite andthe rare sulphates pickeringite and Pit,Dearham, Rosegill Pit and Jane Pit, Bullgill. rozentite (Young and Nancarrow 1988B). The seamdoes not appear to havebeen worked. Ten to 14 m of mainly mudstones lie between the Thestrata between the Ten Quarters and Slaty Fireclay Seam and Black Metal Seam. At seams aremainly mudstone with an increase of Dearham and Bullgill there is athin coal 9 xl11 sandstone in the Dearham area, where a thin coal above the Fireclay Seam. seamoccurs about 30 mabove the Ten Quarters Seam. AtDearham, the thickness ofthe Ten The Black Metal Seam (=Brassy Band) is about Quarters-Slaty interval is 29 m, decreasing north- 0.15 mthick at LonsdaleColliery, Dearham. It is eastwardsto 18 m atJane Pit, Bullgill andto thinat RosegillPit andunrepresented elsewhere. 10.6 m at Oughterside Colliery. About 15 m higher in the sequence at Rosegill Pit thereoccurs another thin coal, the highest seam The SlatySeam, coala typically split by a preservedinthe Dearham-Gilcrux area. This parting, varies inmaximum aggregatethickness may relate either to the Mabel or Brassy seams of from 0.30 m, locally inthe Dearham area, to thearea south of Maryport (Barnes et al. 1987) 1.72 mat Bullgill where at theJane Pit a lower andprobably approaches the inferred position of leaf 0.25 mthick is separated by mudstonefrom the Aegiranum (Bolton) Marine Band. anupper leaf 0.86 mthick. A parting of alittle overmetrea thick in the Slaty Seam inthe Theupper part of the Coal Measuresequence western part of theOughterside OpencastSite preserved in the Dearham-Gilcrux area is affected diminisheseastwards. This is consistentwith the by secondaryreddening and is knownto be absence of a splitin the seam atOughterside devoid of seams at stratigraphical positions which Colliery.Opencast extraction of the two elsewherein thecoalfield would be occupied by components of the seam was carriedout at coals. The positions of thesurviving seams and Oughterside,where old workings in theUpper the distribution of red colour can be expressed in 50 AppliedGeological Mapping of Dearhamand Gilcrux relationto thepersistent White Metal Seam. In St Bees Sandstone theDearham district the highest known seam is Theprincipal exposures of the St Bees Sandstone 27 mabove the White Metaland is succeeded arein the intertidal zone onthe coast north of closely bythe incoming of redcolour. Atthe Bankend,and in disused quarries [0760 39901 on RosegillPit the highestseam preserved is31 m either side of Brunshow Beck north-north-east of abovethe White Metaland is succeeded by red Crosscanonby.Sandstone was formerlyquarried strataonly 3 m higher.In the Crosby Pit the [0895 39331 east of AllerbyHall and poor highest seam is the White Metal itself but the red exposuresexist inGarley Gill [OS10 37701. The colourationbegins here 20 mabove the seam. outcropsshow red-brown massive, laminatedand Again in theEllen Pit, Bullgill, the highest seam cross-laminatedsandstone upto one metre thick is the White Metal,but red colouration is not withthin intercalations of siltymudstone. The recordeduntil 30 mhigher. In the section at the sandstone is fine- to medium-grained,mainly JanePit, Bullgill, the red colouration begins just quartzose and micaceous in places. below the highestpreserved seam at 23m above the White Metal. Therefore although the recorded APPENDIX 5. Details of mineralisation. reddening penetrated down generally to a level 20 to 30 mabove the White MetalSeam, the related Baryte (BaS04)mineralisation is widespreadand oxidation of the coal seams has been effective in conspicuous atoutcrop throughout the Lower places as fardown as the White Metal. The Carboniferousrocks of thedistrict. Trials have absence of seams inthe interval betweenthe beenmade in two fault veins of baryteup to White Metal and the TenQuarters seams at Ellen 0.61 m wide in the Hensingham Group in Rosegill Pit possibly indicatesoxidation of the less [0912 37411 andGreen Gill [0928 37521 west of resistant seams at even lower levels. Gilcrux.Examples of themineral lining joints and minor fault fissures in limestone may be seen The strata preserved above the White Metal Seam, in manyquarries. Baryte also coatsfissures in betweenthe Crosby and Rosegillfaults, is shown some sandstones and locally theHensingham Grit by theRosegill Pit section to be at least 1 14 m is impregnatedwiththemineral. In most thick.Thehigher reddened mudstones and exposures thebaryte coatings are up to 12 cms sandstones of thissequence appear in exposures thick.They commonly consist of pink, relatively along the valleyof theRiver Ellenbetween compactcrystalline baryte adjacent theto Rosegill andCrosby pits. The lowerbeds of the wall-rock,becoming whiteor colourlesstowards reddenedzoneinclude exposed sandstones, the centre of the vein.In some instances, notably formerlymapped as ‘Whitehaven Sandstone’, at at Wardhall Quarry [ 1347 38321, a crudely banded the head of Garley Gill near Dearham. Reddened texture is conspicuouswith open vugs inthe stratawere recorded in the shaft at Oughterside centre of the veins up to 4 cm wide and much Colliery at levels above the Black Metal Seam. as as 3.0 m long elongated parallel to the bedding of the wallrock. Into these vugs project well APPENDIX 4. Details of Permo-Triassic developed whiteor colourless tabular crystalsin stratigraphy. characteristic ‘cockscomb’ aggregates. Inthe old St Bees Shales quarryin the First Limestone north of theradio beacon on Wardhall Common [ 1365 37181 baryte Insouth-west Cumbria, the St Bees Shales are forms large imperfectlydeveloped tabular white considered to span the Permian-Triassic boundary crystals up to 15 cm across coating joint surfaces. (Arthurton et al. Table 4 in Moseley 1958). White crystallinebaryte up to 20 cm thick fills a Inthe Bankend Borehole [0512 38451 thered small north-north-easttrending fault thein mudstones comprising the St Bees Shales are about northernmostworkings of MootaQuarry 81 metresthick, with a thin breccia (0.90 m)at [ 1421 36531 : horizontalslickensiding is theunconformable base. The Crosby Borehole conspicuouson thebaryte. White baryteup to [0824 39611 nearAllerby proved about 50 m 1 cm thick coats a joint in Hensingham Grit in an whilstboreholea onthe coast at BlueDial, old sandstone quarry [ 1167 37631 south of Gilcrux. [0724 40661, shortdistance north of thearea, a Pale pinkbaryte occurs as joint coatingson showed 65.5 m of St Bees Shales (see Appendix coarse-grainedHensingham Grit in oldsandstone 6). pitssouth of GrangeGrassings [1329 3659 and 1325 36401 wheremineralthe also forms conspicuous but patchy impregnations between the AppliedGeological Mapping of Dearhamand Gilcrux 51 grains of sandstone. From thedegraded and Malachite commonly encrusts the chalcopyrite. overgrownstate of these pits it is impossibleto assess the proportion of the sandstone so affected Traces of malachitewere seen in a 15 mm wide butfrom the remaining debris and from stone calcitevein lining a jointin the First Limestone incorporatedinto adjacent dry walls it is clear anin old quarry west of TallentireHill thatbaryte isabundant. Similar joint coatings [ 1 185 35741. A little dolomite is also present. On andimpregnations incoarse-grained sandstone the eastside of TallentireHillmalachite, may beseen in ~ldpits on Wardhall Common accompanied by a little chalcopyrite is common in [ 1395 37291. Thissandstone is inan area of blocks of brecciatedand reddened sandstone in structuralcomplexity but is interpreted as the the base of a hsdge E123535901. Other minerals sandstone beneath the Third Limestone. noted in this material include red earthy hematite, goethite,calcite, quartz and littlea aragonite. Baryte has also been notedforming crystalline Abundant soil brash approximately 200 m further coatings up to 5 mm thick on ganisterexcavated south [1233 35701 shows much reddened sandstone fromthe bed of Flatts e& [I445 39231 nearthe together with blocks up to 10 cm across composed outcrop of the Gilcrux Fault. of palebrown dolomite with some earthy In all of these occurrences baryte is the dominant hematite. Some baryteandrare traces of mineral:only in Msota Quarry has associated malachitehave also beenseen here. Blocks of chalcopyrite been observed. The onlyother siliceoussandstone in a dry wall [ 1207 36001 at associatedminerals noted aregoethite, in part at thefoot of thenorthern side of TallentireHill least replacing original siderite or ankerite, and a exhibit coatingsof quartz,goethite, some of littlecalcite. These minerals clearly post date whichpseudomorphs pyrite, and some malachite. barytedeposition. In a few instances the TallentireHill is virtually free of anyform of limestonewallrock is partiallydolomitised for a superficial deposit other than weathered bed-rock. few mlllimetres adjacentto the baryte vein. The The mineralised rock seen at these points appears barytemineralisation is clearlyepigenetic. In tohave been obtained locally. Itis probable that places themineralisation is developed close to the mineralisation occurs along one or more small major faults, for instance in the Hensingham Grit faultswhich have been mapped in this area. The nearGrange Crossings, in thesandstone and sandstone wall rockseen in the loose blocks is limestone on Wardhall Common andthein probablythe sandstone between the Third and ganister Flatts in Beck. Elsewhere the Fourth Limestone. mineralisation is relativelyremote from these Scatteredcrystals of chalcopyrite upto 1 mm larger fractures though they could well have acted across are present in abundant veinlets lined with as feeders for the mineralisiwg fluids. crystallized siderite,pyrite, millerite and rare Baryte foundlining fissures in a clayironstone sphalerite in beda of clayironstone nodules nodulespoilthefrom in Fretchville Pit approximately 4.0 m below theTenquarters seam 1104538871, Gilcrux is likely to be ofdiagenetic atOughterside Opencast Site [ 110 3981. This origin. mineralisation is likelyto be of diageneticorigin (Young and Nancarrow 1988A). Copperminerdisation. ChalcopyriteCuFeS2 has beennoted in situ inseveral locations and both Zincmineralisation. Palebrown sphalerite (ZnS) chalcopyriteand malachite are common in soil has beenobserved at onepoint in MootaQuarry brash in places. accompanyingchalcopyrite in dolomiteveinlets (see above).A few crystalssphalerite,of Massive chalcopyrite in patches up to 5 cm across probablyof diagenetic origin, accompany other and ! cm thick, locally associated with baryte and sulphides in clay nodules at Oughterside Opencast dolomite, is presentin narrow, almost northerly Site. trending,veins and joint fillings in theFourth Limestone in the centralpart of Moota Quarry Iron mineralisation. littlepyrite A (FeS2) [ 1430 36301. Elsewheretheinquarry [eg accompanieschalcopyrite sphaleriteand in 1415 36481 chalcopyritehas been observed, dolomiteveinlets at MootaQuarry (see above). generallyasisolated crystals on dolomiteand Small crusts of darkbrown mammillated goethite calcite,lining joints which trend betwen 350’ - (Fe”O(0H)) coat the brecciated Fourth Limestone 230’ inthe Fourth Limestone.A few specimens on the west side of the fault between the old and fromMoota showchalcopyrite associated with newworkings of MootaQuarry [ 1463 36271. palebrown sphalerite littlepyrite. anda Goethiteandearthyred hematite (Fe20s) accompanycopper minerals onTallentire Hill 52 Applied Geological Mapping of Dearham and Gilcrux

(see above). Thickness above).[ 1233 35701 (see Depth Nickel inthe form of millerite(NiS) occurs as HAYBOROUGH BOREHOLE [OS89 36001 delicate capillary crystals in clay ironstone nodules (NY 03 NE 4) beneaththe Tenquarters seam Oughtersideat depositsSuperficial 10.82 10.82 Opencastsite (Young and Nancarrow 1988A). The mineralThe is accompanied by pyrite, Hensingham Group chalcopyriteand siderite. This occurrence closely Muds tone, sands tone and resembles those described from the Coal Measures siltstone 51.96 41.14 of South Walesby North (1928). Thesesulphides Coal 52.03 0.07 are likely to be of diagenetic origin. Sandstone,mudstone and 82.4430.41 siltstone Hydrocarbons. Smallpockets of solidblack Sandstone and siltstone with bitumenhave been collected from an outcrop three limestone bands 48.62 131.06 [1334 38011of ThirdLimestone near Eweclose Limestone 4.26135.32 Farm,Plumbland. bitumenThe is not Sandstone and siltstone 1.84137.16 accompanied by any other introduced minerals. It doeshowever resemble closely bitumens recently BANKEND BOREHOLE [0512 38451 found in mineralised fault and joint veins in First (NY 03 NE 3) LimestoneParkat Mead Quarry,Caldbeck depositsSuperficial 10.36 10.36 [340 4071 andTendley Mill Quarry,Eaglesfield [088 2881 andlike these occurrences may Beeshave St Sandstone 86.00 75.64 been introduced during a mineralising episode. StBees Shales,with basal breccia 81 .OO 167.00 Dickite. Smallpockets and veinlets of theclay Coal Measures mineraldickite (A12Si205(OH)4)occur in the Fifth Mudstone,sandstones, coal seams 135.00302.00 Limestoneeast of WardhallCommon [1462 37481 andnear the base of the Fourth Limestone south Hensingham Group of Moota Quarry [1468 35611. Inthe latter Mudstones and sandstones with occurrencethe limestone alsoexhibits veinlets of thin coalseams. A thin baryte.The dickite has probably been introduced fossiliferous limestone at during the mineralising process. 433.60 m 511.00 813.00 CROSBY BOREHOLE [0824 39611 6. Summary logs of boreholes APPENDIX (NY 03 NE 32) mentioned in the text. Superficial depositsSuperficial 2.74 2.74 ThicknessDepth St Bees Sandstone 50.30 BIRKBY MILL BOREHOLE [0520 36951 53.04 (NY 03 NE 5)* Bees St Shales 103.02 49.98 Superficial depositsSuperficial 4.50 4.50 Coal Measures Mainlymudstone with coal seams 58.52 16154 Hensingham Group M udstone and sandstoneMudstone2.20 and 6.70 Hensingham Group Ironstone 0.92 7.62 Mainlymudstone and sandstone 157.59 319.13 Mudstonesandstoneand 17.2 1 24.83 First Limestone First 10.05 329.18 Coal 25.00 0.17 Mudstone and sandstone with several coal seamscoal several 283.00 308.00

*Numbersshown thusregistration theare numbers of boreholesin the BGS fieldrecords collection. AppliedGeological Mapping of Dearhamand Gilcrux 53

ThicknessDepth CROSBY NORTH DRIFT [0412 38591 (NY 03 NE 28) (inclined drift starting at Little Main seam in No 1 or Crosby Pit) Lower Coal Measures Mainly mudstones and sandstones with coal seams below horizon of Little Main seam 109.73 109.73 Hensingham Group MainlySandstone andmudstone 20.43 130.16 Coal 0.30 130.46 Sandstone and mudstone with several beds recorded as "coarse or bastard limestone". Section terminates at fault (Maryport Fault or a branch thereof). Colliery debris at surface was recognised by T Eastwood as identical in appearance with Hensingham Grit, and First Limestone and both of these beds are presumed to have been cut near the termination of drift.the 135.20 265.66 BLUEDIAL BOREHOLE [0724 40661 (NY 04 SE 1) Superficial Deposits 12.34 12.34 St Bees St Sandstone 138.53 150.87 StBees Shales, with basal breccia 65.84 216.71 Lower Coal Measures Mainly mudstone and sandstone with thin coal seams. Stained red in upper 250.85 467.56 Hensingham Group Mudstone and sandstone 254.14 721.70

MINERALISATION SHEETS NY 03 NE & NY 13 NW o r

« 3

MINERALISATION SEEN IN SITU This map should be read In conjunction with the accompanying THIS MAP IS TO BE USED ONLY FOR PRELIMINARY geological report The Geology of the Dearham and Gllcrux area, Cumbria Ba Baryte (Young,B and Armstrong,M 1987) STUDIES AND IS NOT INTENDED AS A SUBSTITUTE Cu Copper minerals FOR ON-SITE INVESTIGATION D Dickite and Kaolinite Any enquires regarding this map should be directed to ­ Fe Iron minerals British Geological Survey, THIS MAP GIVES AN INTERPRETATION OF DATA H Hydrocarbon Windsor Court, AVAILABLE AT THE LAST DATE OF SURVEY. Ni Nickel minerals Windsor Terrace, Newcastle upon Tyne, NE2 4HB ADDITIONAL INFORMATION IS AVAILABLE IN BGS FILES Zn ZinC minerals

MINERALISATION NOT SEEN IN SITU e.g IN SOIL SCALE 1 25 000 BRASH OR LOOSE BLOCKS SHOWN THUS - a 1 2 I I I kilometres STRUCTURE CONTOURS SHEETS NY03 NE & NY 13 NW o I u- CP

THIS MAP IS TO BE USED ONLY FOR PRELIMINARY STUDIES AND IS NOT INTENDED AS A SUBSTITUTE FOR ON-SITE INVESTIGATION

th~f+~ Area contoured in Little Main Seam -- - -- Coal Outcrop THIS MAP GIVES AN INTERPRETATION OF DATA AVAILABLE AT THE LAST DATE OF SURVEY.

_---1..__ Fault at outcrop, crossmark indicates downthrow side. i80 Area contoured in Harrington Four Foot Seam ADDITIONAL INF ATION IS AVAILABLE IN BGS FILES tg ;::::::j Many minor faults omitted.

This map should be read in conjunction with the accompanying m Area contoured on base of First Limestone --- -- Contours in seam or on base of formation geological report: The Geology of the Dearham and Gilcrux area, Cumbria (Young,B. and Armstrong,M. 1987) Broken lines denote uncertainty

W-:~im Area contoured on base of Fourth Limestone Any enquires regarding this map should be directed to :­ British Geological Survey, SCALE 1:25 000 Windsor Court, • Area contoured on base of Fifth Limestone o 1 2 Windsor Terrace, I II I ! I kilometres Newcastle upon Tyne, NE2 4HB. SHALLOW COAL WORKINGS SHEETS NY 03 NE & NY 13 NW

o \

THIS MAP IS TO BE USED ONLY FOR PRELIMINARY MINE WORKINGS WITHIN 30 METRES STUDIES AND IS NOT INTENDED AS A SUBSTITUTE OF GROUND SURFACE This map should be read in conjunction with the accompanying FOR ON-SITE INVESTIGATION geological report: The Geology of the Dearham and Gilcrux area, Cumbria (Young,B. and Armstrong,M. 1987) THIS MAP GIVES AN INTERPRETATION OF DATA AVAILABLE AT THE LAST DATE OF SURVEY. ADDITIONAL INFORMATION IS AVAI LE IN BGS FILES Workings recorded on plans Any enquires regarding this map should be directed to :­ British Geological Survey, .... -:-:, . Some evidence for mining from surface features Windsor Court, {/HHH\ or borehole data, no plans available Windsor Terrace, • Newcastle upon Tyne, NE2 4HB. ·.·., . ··.. Local workings possible [ill·.·.· . SCALE 1:25 000 Workings absent within 30 metres of surface (includes a 1 2 areas where old workings have been removed during I I I D opencast excavations) kilometres