Great Limestone Research Articles

Host-rock lithogeochemistry applicable to exploration in the Hambaeg syncline (Hambaeg Basin), Korea

Cambro-Ordovician sedimentary rocks of the Hambaeg syncline include the Jangsan Quartzite, the Myobong Slate and the Great Limestone Group. Most of the important ore deposits, such as the Sangdong (W), Geodo (Fe-Cu) and Yeonhwa (Pb-Zn) mines are localized at the base of the Great Limestone Group as well as in the interbedded limestones of the Myobong Slate, located on the southern limb of the synclinorium. The northern limb has a high exploration potential for deposits of the same types. Sedimentary rocks around the Sangdong deposit have been analyzed to test the potential of lithogeochemistry in exploring for W in the northern limb. The uppermost interbedded limestone in the Myobong Slate was sampled at intervals of 500 m along a strike length of 16 km, SiO 2, CaO, Fe 2O 3, Zn and Cu are anomalous in areas where exploration drilling has located tungsten bearing skarn at a depth of 400 m. In the Myobong Slate, Fe 2O 3/FeO ratio is lower (about 0.2) near mineralized zones than near barren zones (about 0.6). This is consistent with the formation of the W skarns by relatively reduced fluids. The Sn content of rocks and ores suggests that the alteration is of hydrothermal metasomatic origin, since most of rocks in the mineralized zone show distinctively higher contents of Sn than in unmineralized zones. Geochemical haloes such as those described may prove applicable in exploration for blind ore bodies.

Mixing Zone and Deep Burial Diagenesis: Relevance to Reservoir Porosity and Oil Migration, Middle Jurassic Great Oolite Formation, Wealden Basin, England: ABSTRACT

The Middle Jurassic Great Oolite Limestone of the Wealden basin, southern England, is a target of active exploration owing to recent discoveries of oil, such as the Conoco No. 1 Storrington location. Throughout the basin, similar lithologies in the Great Oolite have porosities ranging from less than 5% to greater than 20%. Hence, the principal control on porosity is a diagenetic history. In the Storrington No. 1 production interval, the porosity is mainly primary. Cement, isotopic, and trace element stratigraphies of that interval indicate that primary porosity is preserved through early mineralogical stabilization of limestones in the mixing zone between freshwater and marine phreatic environments. At the nearby Southwater No. 1 location, studies of the same types of data show a similar early diagenetic history. Following mixing zone diagenesis, further subsidence resulted in deep burial diagenesis, principally the occlusion of porosity by coarse calcite spar. The deep burial origin of the spar is based on fluid inclusion data, which also indicate that uplift followed the precipitation of spar. The amount of uplift varies depending on basin location. Oil-filled fluid inclusions also occur in the spar, indicating oil was in a mobile phase at the time of cementation. Reconstruction of basinmore » structure and maturation modeling show that cementation-oil migration was in the Cretaceous. That, together with the distribution of oil-filled inclusions, indicate the primary areas of the basin where migration and accumulation of oil occurred.« less

A survey of the physical properties of some carbonate rocks

Samples were taken from the Carboniferous Limestone, the Magnesian Limestone, the Inferior Oolitic Limestone and the Great Oolitic Limestone. Their specific gravities, dry and saturated densities were determined, as were their absolute and effective porosities. The densities decreased and porosities increased with decreasing age of the limestone concerned. The permeability of these samples increased as the porosity increased. Furthermore the strength decreased with increasing porosity, that is, the Carboniferous Limestone was very strong whereas the Great Oolitic Limestone was moderately weak. When saturated the strongest limestone showed the least percentage reduction in strength. The strongest limestone also possessed the highest values of hardness, the weakest having the lowest values. As far as Young's modulus was concerned it tended to increase as density, strength and hardness increased. The Carboniferous Limestone recorded the highest values of Young's modulus, the Great Oolitic Limestone the lowest. Poisson's ratio and related elastic properties were also determined.

COAL RANKS ON THE ALSTON BLOCK, NORTH-EAST ENGLAND: A REPLY

Suggate’s discussion of coal ranks on the Alston Block appears to criticise Creaney (1980) in two ways. 1. The attribution of higher pre-Whin Sill reflectance values to reactivation of the Weardale Granite. 2. The discussion of temperatures required to produce the reflectance estimates prior to Whin Sill intrusion. The brief discussion of the general correlation between rank and granite cupolas applies strictly to present day rank levels and not to the relatively precise correlation between pre-Whin Sill rank and cupola position established by Creaney (1980). Present day rank levels are determined largely by the position of the Whin Sill. As is suggested, the temperature/depth question is a complex one. The selection of a vitrinite reflectance of 1.6% as an upper limit for the coking coal range by Creaney (1980) was deliberately a minimum value. This resulted in a minimum temperature estimate of >183°C which, as pointed out, must be applied for the entire 25 million years. Since this would be untenable during the early stages of Great Limestone diagenesis then the application of even higher temperatures, for a shorter time towards the end of the 25 million year period, seems likely. It must also be noted that this temperature was applied at the Great Limestone horizon around the periphery of the subcropping Weardale Granite. In positions directly above the cupola subcrop higher temperatures would be anticipated. Thus, there is a certain amount of evidence that very high temperatures (probably >200°C) existed at the Great Limestone horizon, above granite cupolas, prior …

THE OCCURRENCE OF BITUMEN IN THE GREAT LIMESTONE AROUND MATFEN, NORTHUMBERLAND – ITS CHARACTERISATION AND POSSIBLE GENESIS

SUMMARY The physical and chemical properties of a bitumen located in veins cutting the Great Limestone at Moot Law Quarry (NZ 010768), Northumberland have been assessed and it has been classified as an albertite or epi-impsonite. Several similar occurrences are also described from adjacent Great Limestone quarries including a multiphase bitumen from Kirkheaton (NZ 018773) and a contact metamorphosed bitumen from a quarry near Capheaton (NZ 016787). This Capheaton occurrence exhibits a characteristic mesophase structure implying contact metamorphism by an adjacent Whin dyke. The bitumen is thus pre-Whin dyke in age which allows two possibilities for its genesis: 1. If the Whin dyke post dates the Whin Sill then the bitumen may be a pyrolysate from closer to the sill contact, which has condensed in cooler overlying strata and been metamorphosed by the later dyke. 2. If the Whin dyke and sill were intruded together then the most likely origin of the bitumen is probably related to an earlier period of heating of the Carboniferous sediments overlying the Alston Block to the south.

THE GREAT LIMESTONE (NAMURIAN) OF SOUTH NORTHUMBERLAND

SUMMARY This paper extends the work of Fairbairn (1978) in tracing individual beds and posts of the Great Limestone from the northern part of the Alston Block into the Northumberland Trough. The Bench and Main Posts, forming the lower half of the Great Limestone, when traced northwards from Weardale to Rothbury show little change in thickness and lithology. However, the upper part of the limestone passes gradually northwards into mudstone as a result of the incoming of mudstone partings which thicken and become more numerous towards the north as the limestone posts thin.

PETROGRAPHIC TEXTURE AND VITRINITE REFLECTANCE VARIATION ON THE ALSTON BLOCK, NORTH-EAST ENGLAND

Summary A detailed study of the petrography and vitrinite reflectance of coals has been used to elucidate patterns of heat flow on the Alston Block. Four petrographic/rank vitrinite groups have been distinguished: I. Non-thermally metamorphosed with a vitrinite reflectance below 1.80% (approximately). II. Thermally metamorphosed and showing a granular mosaic. III. Thermally metamorphosed with no granular mosaic. IV. Non-thermally metamorphosed with reflectances in excess of 1.80%. Transitional vitrinites are also described. Certain features of the Group II vitrinites suggest a coking coal rank prior to Whin Sill intrusion and the Group II – Group III transition has been interpreted as a pre-Whin 1.60% isoreflectance contour. This isoreflectance surface has been traced laterally across the block and is shown to dome across the cupolas of the Weardale Granite, indicating that the pre-Whin Sill basement heat flow was channelled through the basement granite stock. Temperatures, calculated by the method of Karweil (1973), for this coalification interval were probably in excess of 185°C at the Great Limestone horizon around the cupola margins. This indicates that some form of rejuvenation of the Weardale Granite occurred at depth, probably in response to the Hercynian orogeny. The intrusion of the Whin Sill (295 ± 6 Ma) produced the Group II and Group III vitrinites and caused an exponential increase in vitrinite reflectance towards its contacts. Graphitisation has occurred immediately adjacent to the Whin Sill in certain localities where pre-Whin Sill rank and intrusion temperatures were favourable. The abnormally wide zone of natural coke above the Whin Sill is attributed to the high background temperatures present in the Alston Block during intrusion. A detailed lateral survey of vitrinite reflectance at the horizon between the Great and Little Limestones has revealed both the dependence of this parameter upon the Whin Sill thickness and stratigraphic horizon in the central part of the block, and a spatial relationship between vitrinite reflectance and the Weardale Granite subcrop around the block margins. The post-Whin Sill mineralisation has had no discernable effect on vitrinite reflectance.

LATERAL PERSISTENCE OF BEDS WITHIN THE GREAT LIMESTONE (NAMURIAN, E 1 ) OF WEARDALE

SUMMARY The widespread lateral persistence of individual beds (posts) of the Great Limestone (Namurian, E 1 ) of Weardale, long suggested by quarry workers, has been confirmed. Variations in thickness and fauna of the posts have been recorded throughout Weardale. Several areas where the Great Limestone is abnormally thin have been noted.

Tightly Appressed Reclined Folds in Jammu Limestone (Great Limestone) of the Himalayan Foothills of Jammu and Kashmir

Tightly Appressed Reclined Folds in Jammu Limestone (Great Limestone) of the Himalayan Foothills of Jammu and Kashmir

THE SEDIMENTARY HISTORY OF A DELTA LOBE FROM A YOREDALE (CARBONIFEROUS) CYCLOTHEM

Summary A delta lobe has been recognised in the Great Limestone (Yoredale) cyclothem over an area of approximately 700 square kilometres in the northern Pennines (Weardale to Stainmore). The lobe occupies the entire clastic interval of the cyclothem and has a complex history of sedimentation involving four distinct phases. The coastal plain phase includes small-scale fluvial channels, and a mudstone-spiculite chert association deposited in a shallow, shoreline bay. This phase preceded lobe development in the Stainmore Trough and was terminated by a localised transgression. In the upstream and intermediate lobe area, the progradational phase consists of small-scale coarsening upwards sequences which represent the repeated infilling of an extensive interdistributary bay by levees, crevasse splays, sand spits and minor mouth bars. Small-scale (crevasse) channels and larger-scale (distributary) channels are associated with these sequences. Farther south the progradational phase comprises a single large-scale coarsening upwards sequence which represents progradation of a river-dominated (mouth bar) shoreline over offshore muds. During the abandonment phase, a thin marker horizon accumulated, comprising coal in the upstream area (widespread marsh development) and fossiliferous sandstone, mudstone and limestone towards the shoreline (reworking and normal sedimentation). This horizon reflects slow deposition rates related to conditions of minimal sediment supply and subsidence. In the post-abandonment phase, sediment supply recommenced and a barrier island—lagoon complex was established on the abandoned lobe. The lagoon facies include small-scale coarsening upwards sequences formed during infilling, in one case by washover fans. The barrier is made up of medium-scale, wave-dominated coarsening upwards sequences which demonstrate contrasted migration trends equivalent in time along the barrier.

A RECORRELATION OF THE YOREDALE LIMESTONES (UPPER VISÉAN) OF THE ALSTON BLOCK WITH THOSE OF THE NORTHUMBERLAND TROUGH

Summary The paper presents a revised and detailed correlation of Yoredale limestones, from the Jew Limestone to the Great Limestone, from the Alston area across Northumberland into southern Scotland. Stratigraphical and micro-palaeontological evidence suggests that the Scar Limestone of Alston is the lateral equivalent of the “Five-Yard” Limestone of Greenhead and consequently of the Eelwell Limestone of north-east Northumberland. Lower in the sequence the Jew Limestone appears to split northwards into the Oxford and Barrasford limestones of Northumberland. Apart from a narrow area of thicker strata on the southern margin of the Northumberland Trough, the higher Yoredale beds in the trough do not exceed greatly in thickness those of the Alston Block.

Factors controlling the mineralogy and chemistry of an Upper Visean sedimentary sequence from Rookhope, County Durham

A series of mineralogical and chemical analyses for a sequence of sediments from the Four Fathom limestone to the base of the Great Limestone are presented. Factor analysis indicates that the variance of the data is controlled by four factors related to depositional processes and two related to diagenesis. The depositional factors include a sorting factor, which dominates the variance, and factors related to relative sedimentation rate, proximity to shoreline and pH of the depositional environment. Diagenetic factors include one relating to the formation of siderite and one to pyrite, the latter perhaps also being influenced by later mineralizing fluids. Limited analyses of the Four Fathom and Iron Post limestones suggest that their chemistry is controlled by slow accumulation of detrital silicates although a “mineralization overprint” may also contribute to the chemistry in small part.

Geotechnical properties of the Great Limestone in northern England

This paper is concerned with the mechanical properties of the Great Limestone in northern England. After first outlining the geological structure of the limestone at East Layton in north Yorkshire, the problem of the basal dolomitization of the limestone is introduced and the geochemistry of the rock profile evaluated. It is shown that chemical alteration due to dolomitization is accompanied by a mechanical weakening of the rock and a reduction in the quality of the bond between a tar or bitumen coating medium and the surface of the stone. The two types of rock are compared via specific gravity, moisture absorption, unconfined compressive strength, aggregate impact and aggregate crushing tests. The results from a detailed series of shear box tests taken through from peak to residual shear strength are interpreted through the fundamental strength properties of calcite and dolomite to show that whereas in the size range 200B.S. sieve, dolomite is a little weaker than limestone due to internal weakness associated with volume change; the situation is reversed as the particles decrease in size to form an aggregate of single dolomite crystals which are inherently more resistant to shear.

Concepts of Equilibrium, Grade and Uniformity as Applied to Slopes

Ford, D. C. 1965 The origin of limestone caverns: a model from the Central Mendip Hills, England. Nat. speleo. Soc. Bull. 27: 27. Sweeting, M. M. 1950 Erosion cycles and limestone caverns in the Ingleborough district. Geogr. J. 115: 63. Waltham, A. C. (1970a) Shale units in the Great Scar limestone of the Southern Askrigg Block. Proc. Yorks geol. Soc. (in press) 1970b Speleogenesis of the caves of Leck Fell, in Limestone and caves of North-west England; Ed. M. M. Sweeting. David and Charles (in press).

GREAT LIMESTONE CAVES FORMED FROM TINY CRACKS

School Science and MathematicsVolume 66, Issue 5 p. 493-493 GREAT LIMESTONE CAVES FORMED FROM TINY CRACKS First published: May 1966 https://doi.org/10.1111/j.1949-8594.1966.tb15048.xCitations: 1AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article.Citing Literature Volume66, Issue5May 1966Pages 493-493 RelatedInformation

Granite beneath Viséan sediments with mineralization at Rookhope, northern Pennines

The geological results of a borehole drilled to investigate the coincidence of centres of a zonal pattern of mineralization ( Dunham 1934 ) with areas of strong negative Bouguer anomaly are presented. The presence of a granite batholith with cupolas, postulated by Bott & Masson-Smith (1957) has been proved; the top surface of the granite was found at 1281ft depth and the boring was continued to 2650 ft in granite. The section begins in the Great Limestone at the base of the Namurian; a normal succession in the Middle Limestone Group (Lower Carboniferous) is revealed, the Smiddy Limestone with Girvanella Band being reached at 1056 ft 6in. The Lower Limestone Group differs from the section in Teesdale and the Pennine escarpment; in particular, beds equivalent to the Melmerby Scar Limestone, identified by their fauna of algae, corals, and brachiopods, have a rubbly lithology and are split by bands of seatearth, sandstone, and shale. Beneath them, clastic sediments 38 ft thick with marine fossils rest on the weathered surface of the granite. Two quartz-dolerite sheets were proved; the Little Whin sill, 6ft, is in the Three Yard Limestone as at Stanhope, while the Great Whin sill, 192ft 9in, lies beneath the Jew Limestone, stratigraphically lower than in Upper Weardale. The Weardale granite, carrying biotite and abundant muscovite, has a low-dipping foliation in the upper part, but this becomes less obvious below 2225ft depth. Preliminary X-ray studies indicate that low albite, orthoclase, maximum microcline, and forms intermediate between the last two are present. Analyses of representative rocks for major and trace elements are given. Xenoliths are conspicuously absent, but aplites and pegmatites are common. The mineralogical and chemical effects of weathering before Carboniferous sedimentation, and of the mineralization, are described. The borehole was sited near the crossing of the Boltsburn lead vein (ene-wsw) and the Red fluorite-iron vein (ese-wnw), both of which dip towards it. Strong metasomatic mineralization, including green fluorite, blende, and quartz occurs in the Tynebottom, Jew, and Lower Little limestones. Numerous small veins were also cut both in the sediments and the granite. Though chalcopyrite is present against the lower sediments, there is no evidence of a concentrated copper zone. Fluorite continues into the granite, and pyrrhotine, not present above, is found from 1355 ft depth. Mineralization continues to much greater depths than have previously been proved in the area; its source presumably lies beneath the granite cupolas, which may, however, have guided the rising fluids.

THE BASE OF THE NAMURIAN AND OF THE MILLSTONE GRIT IN NORTH-EASTERN ENGLAND

Summary During the last few years evidence has been accumulating which has indicated that the junction between the Lower and Upper Carboniferous, the Viséan–Namurian junction, lies in the vicinity of the Great Limestone at the base of the Upper Limestone Group. The zonal evidence for the position of this boundary is reviewed and five new goniatite records from this part of the succession are described. Two have a direct bearing on the boundary problem— Cravenoceras leion Bisat, the basal goniatite of the Namurian, from the shales above the Great Limestone at Greenleighton quarry, Northumberland, and Cravenoceras aff. malhamense (Bisat) from the shales above the Little Limestone in Swinhope Burn, East Allendale. The base of the Namurian is now shown almost certainly to lie between the Four Fathom Limestone and the Great Limestone; the base of the latter is shown to be the nearest suitable mapping horizon for the base of the Millstone Grit Series.

SUB-SURFACE DATA ON THE NAMURIAN STRATA OF ALLENHEADS, SOUTH NORTHUMBERLAND

Summary Four cored boreholes drilled in connection with prospecting operations at the Swinhope lead-zinc mine, East Allendale, have provided for the first time in this area, continuous sections of the strata from the Lower Felltop Limestone down to the Great Limestone for geological investigation. The proportion of marine strata is higher than has previously been supposed, and in addition to fossiliferous shale and sandstone includes several thin limestones. The section is compared with Carruthers’ classic Coalcleugh section, and with the sections recorded by the surveyors of the Beaumont mines at Allenheads. An account of the fauna is included.

Excavations at Hacılar, First Preliminary Report

The village of Hacilar is situated in the Vilayet of Burdur in South-west Anatolia, about 25 km. west of Burdur itself on the main road to Yeşilova and Denizli. The chalcolithic site lies about 1·5 km. west of the village and just beyond the orchards, which are irrigated by a plentiful spring at the foot of a great limestone crag which overlooks the village. It is this spring which since neolithic times has been the main reason for more or less continuous occupation in this region. Apart from the neolithic and early chalcolithic site at Hacılar there is a large Early Bronze Age mound on the northern outskirts and a classical site to the south-west of the village.The prehistoric site is an inconspicuous mound, about 150 metres in diameter, rising to a height of not more than 1·50 m. above the level of the surrounding fields (Fig. 1 and Pl. XXIXa). The entire surface of the mound is under cultivation and a series of depressions show the holes made by a local antique-dealer in search of painted pots and small objects. About 1 km. west of the site runs the Koca Çay, the ancient Lysis, and on the eastern scarp of this river valley lies the cemetery of the Early Bronze Age settlement. Not a single burial has yet been found in the chalcolithic or neolithic levels of our site and it is therefore not unreasonable to suggest that its cemetery also may eventually be located there.

Chemical Component of Cambro-Ordovician L'mestone

The writer dealt with the Great Limestone Series, from middle Cambrian to middle Ordovician in age, of Sosan district of North Korea chemically and protted the data of analysis of them in CaO-MgO-Clay part diagram. The contents of MgO are well defined to each stratigraphical units but the contents of clay part are not so well defined to each units as in MgO, and shown some variations in the same unit.