942:
402:
394:
211:
569:
573:
porphyritic G3a granite with abundant orthoclase phenocrysts (> 25 mm) from the
Dartmoor Granite. E – Globular quartz G4b granite from Carn Dean Quarry, Land's End Granite. F – Pegmatitic pocket dominantly comprising tourmaline, orthoclase and quartz within G3a granite, Land's End Granite. G – Typical topaz (G5) granite texture, equigranular with abundant Li mica, Tregonning Granite. Mineral name abbreviations: Kfs = potassium feldspar, Bt= biotite, Msc = muscovite, Qtz = quartz, Tur = tourmaline, Mca = mica.
578:
1190:
325:
293.1±3 Ma. The youngest dated granite is the southern lobe of the Land's End pluton, intruded at 274.5±1.4 Ma. The earliest recorded magmatic activity is the intrusion of the small
Hemerdon pluton on the southwestern flank of the Dartmoor pluton at 298.3±2.3 Ma. There is no apparent systematic variation in age of plutons compared to their position within the batholith. This suggests that the batholith grew by the coalescence of a series of separate intrusions over a period of about 25 Ma.
508:
382:
22:
2412:
370:
904:
922:
2426:
593:
140:
459:
granites at the western end, a medium-grained granite is developed with lithium-mica. Smaller bodies of fine-grained granite are found in the central part of the outcrop and at the western end. Gravity data indicate that this pluton is wedge-shaped similar to that at Bodmin. Monazite gives an emplacement age of 281.8±0.4 Ma for this pluton.
433:
that it is sheet-like with a thickness of nearly 10 km, and a root at its southern end extending down to about 17 km depth, which may represent the conduit that carried the magma to shallow crustal levels. It appears to have been intruded along the interface between
Devonian and Carboniferous rocks.
1127:
The third and main phase of mineralization occurred at a later stage, and at lower temperatures (200 – 400 °C) as the granite intrusion cooled. Fluids circulating within the country rock leached out tin, copper and arsenic and deposited them in veins which generally lie on an east–west axis. The
498:
and monazite samples, from a fine-grained granite and the main coarse-grained granite respectively. These give emplacement ages of 279.3±0.4 Ma for the fine-grained granite and 274.8±0.5 Ma for the main phase granite. This difference is consistent with fine-grained granite being a roof-pendant to the
572:
Field photographs of
Cornubian Batholith granites. A – Typical G1a granite with orthoclase phenocrysts (< 25 mm) from the Carnmenellis Granite. B – Enclave of G1c granite within G1a granite, St. Agnes, Isles of Scilly Granite. C – Cligga G2 Granite with sheeted W greisen veins. D – Coarse-grained
530:
This submarine outcrop, 45 km in length, lies 95 km northwest of the Scilly Isles, rising at one point to 38 m below sea level. In contrast to most granites of the
Cornubian batholith the granites here are fine to medium-grained and generally lack megacrysts. It was intruded at 277 Ma
515:
The Isles of Scilly all have granite bedrock. The dominant rock type is a megacrystic biotite granite, although the megacrysts are relatively small. In the centre of the pluton a medium-grained granite is developed with few megacrysts, more tourmaline and less biotite than the main variety. Monazite
360:
Evidence for a stoping mechanism has been described locally from the margin of the
Tregonning intrusion, where a series of intrusive sheets extend out from the roof zone of the intrusion into the country-rock. Although the Land's End pluton was once thought to have a diapiric origin, its emplacement
1201:
are found in places across the south-west peninsula, in particular Lee Moor on the western edge of
Dartmoor and the St Austell district. The china clay was formed by the alteration of feldspars in a process known as kaolinization. There is still debate about the origin and age of these deposits but
449:
The Bodmin Moor pluton consists mainly of coarse-grained granite with abundant small megacrysts. Towards the centre and the western margin of the outcrop there are smaller bodies of fine-grained granite. Gravity data suggest that this pluton is in the form of a south-southeastward thickening wedge,
432:
and coarse-grained granite with few megacrysts. To the southwest there is an area of coarse-grained granite with small megacrysts and several small exposures of fine-grained granite, particularly in the southeastern part of the outcrop. Interpretation of the gravity field over this pluton suggests
467:
The
Carnmenellis pluton and the smaller intrusion of Carn Brea appear to be part of a single intrusive body. The central part of the Carnmenellis outcrop is a medium-grained granite with few megacrysts. The bulk of the main outcrop and the Carn Brea and Carn Marth masses consist of coarse-grained
458:
The St
Austell pluton consists of coarse-grained megacrystic granite with large megacrysts at the western and eastern ends of the outcrop. The central part of the pluton is also coarse-grained but lacks the megacrysts. Between the central megacryst poor and the large megacryst rich coarse-grained
324:
The inferred age of emplacement from this evidence of Late
Carboniferous to Early Permian has been confirmed by radiometric dating, although it has shown that the individual intrusions were emplaced over a significant time interval. The earliest dated major intrusion is the Carnmenellis pluton at
773:
Differences in chemistry have been identified between an earlier group of plutons (Isles of Scilly, Carnmenellis & Bodmin Moor) and a later group (Land's End, St Austell & Dartmoor). The early group of granites contain more aluminium than the later set and have steeper slopes on plots of
484:
The Tregonning Granite and Godolphin Granite are two distinct granite bodies on the southern coast of Cornwall. The Tregonning Granite is mainly a medium-grained lithium-mica granite with a body of fine-grained granite developed towards the northwest of the outcrop. It has a unique chemistry and
416:
that comprise the Cornubian Batholith can be broadly subdivided into five main lithologies: Two mica, Muscovite, Biotite, Tourmaline and Topaz granites, each named for their distinguishing mineral(s). The two-mica and muscovite granites are older, and can be found in the Carnmenellis, Bodmin and
277:
it solidified and crystallised and fractures along vertical joints formed. Over time the slate and sandstone rocks covering the granite were eroded exposing the granite in areas such as Dartmoor and Bodmin Moor. The granite also expanded and horizontal joints were formed. These joints are most
878:
components. Fluids rich in these have strongly affected the country rock and locally the granites themselves in a process called metasomatism. The first phase recognised is alkali metasomatism (where alkaline components are enhanced), which occurred within and at the margins of the granite.
468:
megacrystic granite with small megacrysts. Small bodies of fine-grained granite are found towards the west of the Carnemellis outcrop. The shape of this pluton is interpreted to be a sheet about 3 km thick with a near central root extending down to about 7 km depth. Boreholes at
831:. The effects of this can be seen up to a distance of 4 miles from the granite in an area called the metamorphic aureole. The effect of this process depends on the type of rocks which were heated and their distance from the intrusion. Fine grained sedimentary rocks were transformed into
493:
The Land's End pluton is mainly a coarse-grained granite with abundant large megacrysts. There is an area in the centre which is poor in megacrysts and there are several small and medium-sized masses of fine-grained granite throughout the outcrop. Dating has been carried out on
963:
deposits are found in the vicinity of the batholith and these have been mined for thousands of years. The area has been famous for its tin since about 2000 BC. The minerals formed when fluids escaped along fractures in the hot granite as it cooled and are typically found in
202:. Comparisons with other examples would suggest that the thicknesses of the individual plutons would be in the range 3–5 km, based on their outcrop widths. The volume of the batholith was estimated in 1989 to be around 68,000 cubic kilometres.
170:, the batholith is interpreted to extend from about 8°W, more than 100 km southwest of the Isles of Scilly, to the eastern edge of Dartmoor. The negative gravity anomaly, caused by the relatively low density of the granites compared to average
1797:
Müller, Axel; Seltmann, Reimar; Halls, Christopher; Siebel, Wolfgang; Dulski, Peter; Jeffries, Teresa; Spratt, John; Kronz, Andreas (April 2006). "The magmatic evolution of the Land's End pluton, Cornwall, and associated pre-enrichment of metals".
1664:
Simons, B.; Shail, Robin K.; Andersen, Jens C.Ø. (September 2016). "The petrogenesis of the Early Permian Variscan granites of the Cornubian Batholith: Lower plate post-collisional peraluminous magmatism in the Rhenohercynian Zone of SW England".
485:
differs from the granite found within the Carnmenellis and Land's End granites, likely forming in a different manner. The Godolphin Granite is mineralogically and chemically similar to the nearby Carnmenellis Granite, although is finer grained.
615:
cooled slowly, covered by 2–3,000 metres of slate and sandstone. The slow cooling gave time for crystals to form in the granite which are large enough to see with the naked eye, giving it a granular appearance. These grains are mainly of
678:-mica granite forms a less common type found only in the St. Austell pluton and some smaller intrusions. Many of the granites contain large alkali feldspar phenocrysts. In some locations the original granite has been modified to form a
1140:, with tin, copper, lead, zinc, iron and arsenic sulfides. This mineralization is 25–40 Ma later than the intrusion age for the Carnmenellis pluton. These veins are the main economically useful source of minerals.
417:
Isles of Scilly, whereas the younger biotite and tourmaline granites are found within the Land's End, St. Austell and Dartmoor plutons. Topaz granites outcrop within the Tregonning, Land's End and St Austell plutons.
819:. The relatively high ammonium content is interpreted to indicate that the granites were derived from a sedimentary protolith, or have been contaminated from such a source after emplacement to high crustal levels.
539:
Minor granitic intrusions are present throughout the peninsula. In some cases granitic bodies have been recognised from the mineralization above them, even if the intrusion itself has not been encountered.
193:
suggested that the batholith had an overall trapezoidal shape with a base to the batholith at about 10–12 km. However, current understanding of granite pluton shape suggest that most are either
1712:"Fractionation of Li, Be, Ga, Nb, Ta, In, Sn, Sb, W and Bi in the peraluminous Early Permian Variscan granites of the Cornubian Batholith: Precursor processes to magmatic-hydrothermal mineralisation"
698:– they have a high ratio of aluminium oxide to sodium and potassium oxides. They also have a low ratio of sodium to potassium and overall high level of alkalis. The granites are highly enriched in
425:
This is the largest exposed area of granite which also forms the easternmost development of the batholith. The granite consists of two main types, coarse-grained granite with abundant large
189:
and the main mass of the granite remained entirely speculative until gravity data began to be used to constrain the thickness and shape of the batholith by modelling. The initial work by
1003:
The earliest phase of mineralization occurred during the intrusion of the granite. Hot water from the magma which was rich in silica, iron, aluminium, and magnesium mixed and dissolved
992:
minerals. The first three stages have been connected to the intrusion and cooling of the batholith, while the fourth stage may have been driven by the heat production associated with
1156:). The veins lie on a north–south or northwest–southeast axis and are known as 'crosscourses' because they cross-cut the earlier E-W trending veins. Gangue minerals include quartz,
1148:
The fourth and final stage of mineralization was the lowest temperature phase (100 – 170 °C) and is associated with veins containing multiple metallic elements (lead, zinc,
1067:. These minerals were formed at about the same time as the crystallisation of the pluton they are associated with. Temperatures associated with this stage were 375 – 450 °C.
976:
and fractures that dip steeply and cut across both the granites and the country rocks. The ore-bearing lodes are up to several kilometres long and are 0.5 to 3m wide on average.
1168:
which are rich in sodium, calcium and chlorine. This brine came from Permo-Triassic sedimentary rocks that once covered the entire area. These rocks are still preserved in the
789:
The granites are generally rich in ammonium compared to average granites worldwide. There is also considerable variation between the individual plutons, with an average of 11
988:
associated with different conditions as the granite slowly cooled. Each stage is associated with different temperatures, economic deposits of different metals and different
2264:
Gleeson, S.A.; Wilkinson J.J.; Stuart F.M.; Banks D.A. (2001). "The origin and evolution of base metal mineralizing brines and hydrothermal fluids, South Cornwall, UK".
143:
Bouguer gravity anomaly map over southwestern Britain showing the linear negative anomalies associated with the Cornubian batholith and the Haig Fras granite
317:(fragments of the granite which have weathered away and become part of a new sedimentary rock) in younger sedimentary sequences is from the Late Permian
298:
rocks – both those which formed before the intrusion and those which were laid down after it. The youngest rocks into which the granites intrude are the
1075:
The second recognised phase of mineralization involved the granite being transformed by high-temperature late magmatic fluids rich in volatiles to form
29:. The dotted line shows the area of negative gravity anomalies associated with these batholiths due to their relatively low density compared to average
1539:"Thermochronology of the Cornubian batholith in southwest England: Implications for pluton emplacement and protracted hydrothermal mineralization"
25:
Map showing the main granite outcrops of the Cornubian batholith in southwest England and the location of another granite outcrop called the
2088:
686:. This tourmalinisation occurred during the late stages of cooling of the granite, as feldspar and mica were partly replaced by tourmaline.
891:–metasomatism. Finally acid metasomatism (enrichment of acid components and depletion of alkalis) took place leading to the formation of
793:
for Dartmoor compared to 94 ppm for Bodmin Moor. The concentration of ammonium in these granites correlates well with both their initial
337:
is a matter of debate, due to the space problem of adding such large masses to the upper crust. Four main mechanisms have been proposed;
2439:
1091:(a mineral containing iron, manganese and tungsten) are found associated with the greisens, the former deposited by high salinity, low
1206:(water from rain or snow) at a late stage during cooling of the batholith. One theory is that the kaolinization resulted from intense
1019:, where the chemical composition of rocks is changed by hot water or other fluids. Typical minerals formed at this time include
2393:
2248:
1600:
1428:"Information Sheet 1B: Late Lower to Upper Carboniferous: Crackington Formation (Culm Basin 'autochthon' / 'parautochthon')"
1380:
762:(a variety of sandstone). The conditions under which the melts formed is modelled to be temperature of 770 °C and a
531:
and is considered most likely to be a separate but related intrusive body that runs parallel to the Cornubian batholith.
476:
composition of the granite with depth in this pluton. Monazite gives an emplacement age of 293.7±0.6 Ma for this pluton.
2312:
2304:
2186:
2178:
2126:
2118:
2215:
2072:
1479:"Diachronous and independent histories of plutonism and mineralization in the Cornubian Batholith, southwest England"
1193:
Satellite image of south-west England showing lighter areas that mark the location of china clay workings (labelled)
2462:
639:
The chemistry and mineralogy of the granites vary from one location to another, but they are all classified on the
2015:
1427:
1397:
1988:
Jones, D.G.; Miller J.M.; Roberts P.D. (1988). "A seabed radiometric survey of Haig Fras, S. Celtic Sea, U.K.".
282:
of Dartmoor and Bodmin Moor. As the granite erodes further, blocks of eroded granite known as clitter are left.
1449:
406:
1398:"Information Sheet 1D: Blackdown Nappe: Late Lower to Upper Carboniferous, Bealsmill Formation ('allochthon')"
827:
Around the edges of many of the plutons the country rocks have been transformed by heat in a process known as
2511:
1963:
543:
A series of minor intrusions are found within the country rock and the granites themselves. Common types are
334:
2038:
1636:
2501:
1911:
954:
450:
reaching a maximum of about 7 km. Monazite from this pluton gives an emplacement age of 291.4±0.8 Ma.
1876:
2526:
843:. At greater distances from the plutons, the only evidence of metamorphism is spotting in these rocks.
1538:
1180:
marine incursion at the earliest. The high heat flow from the granites helped drive fluid circulation.
2506:
1837:
758:
are relatively depleted. This chemistry is consistent with partial melting of a source consisting of
164:
2516:
985:
1937:
941:
1478:
875:
2329:
2240:
1336:
1296:
1269:"Interpretations of seismic and gravity surveys over the eastern part of the Cornubian platform"
640:
2143:
1176:. Evidence of seawater influence suggests that the mineralization did not start until the Late
401:
346:
2203:
1590:
1268:
1164:
have shown that the fluids causing this stage are similar in composition to deep sedimentary
1119:
within the greisens give cooling ages similar to magmatic muscovites in the relevant granite.
2273:
1553:
1450:"Unroofing of the Dartmoor granite and possible consequences with regard to mineralization"
1169:
828:
361:
is now interpreted to have been accommodated by fault movements during regional extension.
279:
8:
1617:
1207:
434:
307:
139:
2277:
1557:
1477:
Chen, Y.; Clark A.H.; Farrar E.; Wasteneys H.A.H.P.; Hodgson M.J.; Bromley A.V. (1993).
310:
age. This provides a lower bound for the timing of granite emplacement of about 310 Ma.
2233:
1782:
1765:
915:
291:
2285:
2001:
246:
isotopes suggests that the magmas that formed the batholith were mainly the result of
2389:
2308:
2244:
2211:
2182:
2122:
2068:
1838:"The early Cornubian plutons: a geochemical study, comparisons and some implications"
1815:
1739:
1692:
1596:
1565:
1376:
790:
695:
628:. The granite is generally coarse grained and in some places very coarse-grained, or
338:
235:
171:
30:
1811:
1337:"Nd and Sr isotope constraints on the origin of the Cornubian batholith, SW England"
2521:
2363:
2281:
2155:
1997:
1807:
1777:
1729:
1719:
1710:
Simons, Beth; Andersen, Jens C.Ø.; Shail, Robin K.; Jenner, Frances E. (May 2017).
1682:
1674:
1569:
1561:
1490:
1348:
1308:
1297:"Pluton shapes in the Cornubian Batholith: new perspectives from gravity modelling"
1275:. Special Publications. Vol. 14. London: Geological Society. pp. 119–124.
1161:
946:
648:
255:
238:) allowed the granitic magmas to move to higher levels in the crust. Evidence from
227:
160:
1766:"The Cornubian Batholith: an Example of Magmatic Fractionation on a Crustal Scale"
393:
2417:
1724:
1711:
1678:
1173:
582:
568:
426:
259:
251:
247:
223:
85:
37:
577:
226:(million years ago) at a late stage in the mountain-building event known as the
1534:
1203:
1133:
965:
911:
354:
350:
290:
An approximate age of emplacement for the Cornubian batholith was known before
152:
128:
1312:
2495:
2477:
2464:
2367:
2159:
1819:
1743:
1696:
1494:
1352:
1189:
767:
525:
472:
that extend to over 2.5 km deep have shown very little variation in the
441:
from this intrusion gives emplacement ages of 278.2±0.8 Ma and 280.4±1.2 Ma.
299:
81:
61:
2446:
The Tectonics of Variscan Magmatism and Mineralisation in South West England
210:
155:
formed from the crystallization of molten rock beneath the Earth's surface (
2431:
1938:"Offshore Special Area of Conservation: Haig Fras SAC Selection Assessment"
1016:
884:
816:
683:
596:
318:
314:
263:
214:
Hound Tor on Dartmoor showing horizontal and vertical joints in the granite
77:
2263:
558:
1574:
1476:
1084:
1040:
993:
907:
874:
A feature of the granites of the batholith is the high concentrations of
868:
860:
633:
507:
473:
469:
381:
295:
267:
190:
93:
69:
333:
As with all large intrusive bodies, the method by which the batholith's
1734:
1687:
1214:
1210:
1088:
1080:
1032:
1008:
864:
848:
743:
679:
600:
219:
174:, is linear and trends WSW-ENE, parallel with that associated with the
167:
101:
73:
34:
1532:
636:, several centimetres long, of K-feldspar, are a distinctive feature.
258:
source. This lower crustal source is likely to have consisted of both
234:
granites. It has been suggested that stretching of the Earth's crust (
21:
1877:"The Variscan Granites of south-west England: additional information"
1222:
1198:
1116:
1036:
903:
880:
852:
836:
759:
723:
667:
651:
629:
585:
544:
429:
386:
369:
342:
294:
methods became commonplace, from the observed relationships with the
243:
239:
195:
182:
175:
148:
52:
rock, formed about 280 million years ago, which lies beneath much of
26:
921:
2453:
2449:
1935:
1634:
1226:
1218:
1177:
1137:
1044:
1024:
969:
926:
856:
840:
832:
783:
763:
751:
739:
735:
731:
727:
715:
621:
495:
438:
303:
231:
199:
117:
89:
65:
53:
2144:"The distribution of ammonium in granites from South-West England"
1072:
Stage 2 – greisen bordered veins and tourmaline veins and breccias
1637:"Emplacement styles within the Land's End Granite, west Cornwall"
1153:
1076:
1064:
1048:
1028:
960:
934:
930:
892:
779:
719:
711:
707:
699:
675:
671:
625:
608:
274:
100:
which has been mined since about 2000 BC. Other minerals include
49:
1157:
1149:
1129:
1056:
1020:
989:
888:
844:
822:
775:
747:
617:
592:
548:
413:
374:
186:
105:
1537:; Snee L.W.; Mezger K.; Shepherd T.J.; Scrivener R.C. (1993).
1961:
1165:
1012:
1004:
703:
612:
552:
516:
from this pluton suggest an emplacement age of 290.3±0.6 Ma.
511:
Looking across Tresco, the second-largest of the Scilly Isles
156:
88:. The intrusion is associated with significant quantities of
57:
1987:
2039:"Insights into the formation of the Isles of Scilly pluton"
1202:
they are commonly thought to arise from the circulation of
1060:
973:
755:
663:
113:
109:
2018:. University College London, Department of Earth Sciences
1796:
1709:
1052:
782:. The later group contain more common basic microgranite
97:
2384:
Selwood, E. B.; Durrance, E. M.; Bristow, C. M. (1998).
2036:
1334:
559:
Mineralogy and chemistry of the granite and other rocks
2383:
2298:
2235:
Nature's building blocks: an A-Z guide to the elements
2210:. Springer Science & Business Media. p. 241.
2172:
2112:
1874:
1635:
Powell, T.; Salmon S.; Clark A.H.; Shail R.K. (1999).
1447:
2407:
2239:. Popular Science. Oxford University Press. p.
972:. The mineral deposits are associated with multiple
647:, which means that they are ultimately derived from
2352:
studies of kaolinite and other alteration minerals"
2299:Edmonds, E.A.; McKeown, M.C.; Williams, M. (1969).
2173:Edmonds, E.A.; McKeown, M.C.; Williams, M. (1969).
2113:Edmonds, E.A.; McKeown, M.C.; Williams, M. (1969).
1663:
662:
The Cornubian intrusions are mostly made up of two-
345:, extensional faulting and uplift of the overlying
278:clearly seen on exposed pieces of rock such as the
2232:
1962:Edwards, J.W.F.; Briant, M.; Arthur, M.J. (1991).
64:. The main exposed masses of granite are seen at
2493:
2204:"Intrusion-related hydrothermal mineral systems"
254:with a minor component of basaltic magma from a
1909:
1763:
1273:Variscan Tectonics of the North Atlantic Region
1271:. In Hutton D.H.W. & Sanderson D.J. (ed.).
2440:Nick LeBoutillier's website on Cornish Geology
2330:"The Cornubian Batholith, SW England: D/H and
1870:
1868:
1866:
1864:
1862:
1860:
1858:
1103:, fluids and the latter by low salinity, high
2037:Mullis, S.J.L.; Salmon S.; Powell T. (2001).
1831:
1829:
1435:Meldon Geology & Geomorphology Case Study
1405:Meldon Geology & Geomorphology Case Study
1051:. The skarns may contain economic amounts of
742:. Given the overall chemistry, the levels of
499:coarse-grained main phase granite intrusion.
321:. This gives an upper bound of about 250 Ma.
270:age (2500 million to 539 million years old).
1955:
1936:Joint Nature Conservation Committee (2008).
1912:"Geochemistry of the Isles of Scilly pluton"
1615:
1609:
823:Associated metamorphic and metasomatic rocks
185:and the relationship between the individual
2303:. British Regional Geology (3rd ed.).
2292:
2177:. British Regional Geology (3rd ed.).
2117:. British Regional Geology (3rd ed.).
1964:"Proposed Mesozoic dykes in the Celtic Sea"
1855:
1759:
1757:
1755:
1753:
1595:(3 ed.). Routledge. pp. 128–129.
1528:
1526:
1524:
1441:
979:
328:
2208:Hydrothermal processes and mineral systems
1990:Proceedings of the Geologists' Association
1903:
1826:
1522:
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1518:
1516:
1514:
1512:
1510:
1508:
1506:
1504:
1335:Darbyshire, D.P.F.; Shepherd T.J. (1994).
1124:Stage 3 – the main phase of mineralization
218:The Cornubian batholith formed during the
1781:
1733:
1723:
1686:
1573:
1366:
1364:
1362:
1328:
1213:in a tropical to warm climate during the
273:As the molten rock cooled to around 1000
2327:
2321:
2065:The Geology of Cornwall, an introduction
2062:
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1750:
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1288:
1286:
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1282:
1188:
940:
920:
902:
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400:
392:
380:
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302:Crackington and Bealsmill formations of
209:
138:
20:
2257:
2201:
2195:
1501:
1370:
1266:
607:The main rock forming the batholith is
479:
2494:
2230:
2224:
2030:
1628:
1616:Leboutillier, Nick (22 January 2003).
1472:
1470:
1359:
1294:
1260:
863:has generally led to the formation of
632:(grains larger than 3 cm). Large
134:
1981:
1875:Dangerfield, J.; Hawkes J.R. (1981).
1835:
1659:
1657:
1448:Dangerfield, J.; Hawkes J.R. (1969).
1279:
2444:Nick LeBoutillier's D.Phil. thesis:
2141:
2135:
1929:
1588:
1582:
1425:
1419:
1395:
984:There are four recognised stages of
898:
2008:
1467:
1437:. Dartmoor National Park Authority.
1389:
694:The two-mica granites are strongly
641:Chappell & White classification
534:
13:
1783:10.1111/j.1751-3928.2006.tb00281.x
1654:
1407:. Dartmoor National Park Authority
588:, Dartmoor (photo by Ian Stimpson)
581:Coarse-grained granite with large
502:
405:Granite at Trenemene, part of the
313:The earliest instance of granitic
60:in the south-western peninsula of
14:
2538:
2403:
2356:Journal of the Geological Society
2148:Journal of the Geological Society
1971:Proceedings of the Ussher Society
1919:Proceedings of the Ussher Society
1884:Proceedings of the Ussher Society
1483:Journal of the Geological Society
1457:Proceedings of the Ussher Society
1375:. Bosiney Books. pp. 10–12.
1341:Journal of the Geological Society
1301:Journal of the Geological Society
353:with a relatively small vertical
16:Granite rock in southwest England
2424:
2410:
2046:Geoscience in South-west England
1845:Geoscience in South-west England
1764:Chappell, B.W.; Hine R. (2006).
1644:Geoscience in South-west England
1592:Foundation of Structural Geology
1373:Devon's Geology, an introduction
1160:and fluorite. Studies on quartz
945:Lee Moor china clay pit showing
2305:Her Majesty's Stationery Office
2266:Geochimica et Cosmochimica Acta
2179:Her Majesty's Stationery Office
2166:
2119:Her Majesty's Stationery Office
2106:
2081:
1894:
1812:10.1016/j.oregeorev.2005.05.002
1790:
1703:
1546:Geochimica et Cosmochimica Acta
1128:typical fill of these veins is
968:or washed into streams to form
462:
2388:. University of Exeter Press.
1910:Stone, M.; Exley C.S. (1989).
1319:
444:
407:Western Rocks, Isles of Scilly
222:period, from about 300 to 275
33:. The lines represents the 20
1:
2286:10.1016/S0016-7037(01)00579-8
2002:10.1016/S0016-7878(88)80035-X
1254:
1184:
657:
488:
453:
397:Granite outcrop at Land's End
1725:10.1016/j.lithos.2017.02.007
1679:10.1016/j.lithos.2016.05.010
1566:10.1016/0016-7037(93)90115-D
955:Mining in Cornwall and Devon
689:
519:
205:
7:
2328:Sheppard, S. M. F. (1977).
1900:Selwood et al., p. 121
1325:Selwood et al., p. 120
1197:Large economic deposits of
420:
10:
2543:
2377:
1011:, and converted them into
996:materials in the granite.
952:
746:are also high. Strontium,
563:
523:
364:
2089:"The Cornubian Batholith"
2063:Westwood, Robert (2004).
2016:"The Geology of Cornwall"
1313:10.1144/0016-76492006-104
666:granite (containing both
285:
2368:10.1144/gsjgs.133.6.0573
2160:10.1144/gsjgs.145.1.0037
1495:10.1144/gsjgs.150.6.1183
1371:Hesketh, Robert (2006).
1353:10.1144/gsjgs.151.5.0795
1267:Edwards, J.W.F. (1984).
980:Stages of mineralization
682:-bearing granite called
526:Haig Fras § Geology
329:Mechanism of emplacement
2386:The Geology of Cornwall
1622:Cornish Geology Website
123:It takes its name from
1221:, based on studies of
1194:
1145:Stage 4 – crosscourses
950:
938:
918:
859:. The metamorphism of
750:and the elements from
604:
589:
574:
512:
409:
398:
390:
378:
215:
144:
41:
2067:. Redruth: Tor Mark.
1295:Taylor, G.K. (2007).
1192:
944:
924:
906:
835:and minerals such as
714:and moderately so in
595:
580:
571:
510:
404:
396:
384:
372:
335:plutons were emplaced
213:
142:
24:
2512:Batholiths of Europe
2202:Pirajno, F. (2009).
1718:. 278–281: 491–512.
1170:Southwest Approaches
1015:in a process called
937:District of Cornwall
925:Wolframite from the
829:contact metamorphism
611:, which formed when
480:Tregonning-Godolphin
2502:Geology of Cornwall
2474: /
2278:2001GeCoA..65.2067G
2231:Emsley, J. (2003).
1800:Ore Geology Reviews
1589:Park, R.G. (2004).
1558:1993GeCoA..57.1817C
1426:Page, K.N. (2006).
1396:Page, K.N. (2006).
1000:Stage 1 – exoskarns
435:Uranium-lead dating
349:over a laccolithic
230:as a suite of late
151:is a large mass of
135:Extent and geometry
131:name for Cornwall.
48:is a large mass of
46:Cornubian batholith
2301:South West England
2181:. pp. 49–50.
2175:South West England
2115:South West England
2093:UCL Earth Sciences
1836:Stone, M. (2000).
1618:"Megiliggar Rocks"
1195:
951:
939:
919:
764:confining pressure
605:
590:
575:
513:
410:
399:
391:
379:
292:radiometric dating
216:
145:
42:
2527:Permian magmatism
2395:978-0-85989-432-6
2272:(13): 2067–2079.
2250:978-0-19-850340-8
2142:Hall, A. (1988).
2121:. pp. 48–9.
1602:978-0-7487-5802-9
899:Mineral formation
895:and tourmalines.
851:rocks as well as
815:ratios and their
236:crustal extension
181:The shape of the
172:continental crust
31:continental crust
2534:
2507:Geology of Devon
2489:
2488:
2486:
2485:
2484:
2479:
2475:
2472:
2471:
2470:
2467:
2434:
2429:
2428:
2427:
2420:
2415:
2414:
2413:
2399:
2372:
2371:
2351:
2349:
2348:
2340:
2338:
2337:
2325:
2319:
2318:
2296:
2290:
2289:
2261:
2255:
2254:
2238:
2228:
2222:
2221:
2199:
2193:
2192:
2170:
2164:
2163:
2139:
2133:
2132:
2110:
2104:
2103:
2101:
2099:
2085:
2079:
2078:
2060:
2054:
2053:
2043:
2034:
2028:
2027:
2025:
2023:
2012:
2006:
2005:
1985:
1979:
1978:
1968:
1959:
1953:
1952:
1950:
1948:
1942:
1933:
1927:
1926:
1916:
1907:
1901:
1898:
1892:
1891:
1881:
1872:
1853:
1852:
1842:
1833:
1824:
1823:
1794:
1788:
1787:
1785:
1770:Resource Geology
1761:
1748:
1747:
1737:
1727:
1707:
1701:
1700:
1690:
1661:
1652:
1651:
1641:
1632:
1626:
1625:
1613:
1607:
1606:
1586:
1580:
1579:
1577:
1552:(8): 1817–1835.
1543:
1530:
1499:
1498:
1489:(6): 1183–1191.
1474:
1465:
1464:
1454:
1445:
1439:
1438:
1432:
1423:
1417:
1416:
1414:
1412:
1402:
1393:
1387:
1386:
1368:
1357:
1356:
1332:
1326:
1323:
1317:
1316:
1292:
1277:
1276:
1264:
1250:
1248:
1247:
1239:
1237:
1236:
1162:fluid inclusions
1114:
1113:
1112:
1102:
1101:
1100:
1087:(tin oxide) and
1031:, chlorine-rich
947:hydraulic mining
887:was followed by
814:
812:
811:
803:
801:
800:
649:sedimentary rock
535:Other intrusions
228:Variscan orogeny
168:geophysical data
2542:
2541:
2537:
2536:
2535:
2533:
2532:
2531:
2517:Permian England
2492:
2491:
2482:
2480:
2476:
2473:
2468:
2465:
2463:
2461:
2460:
2430:
2425:
2423:
2418:Cornwall portal
2416:
2411:
2409:
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2380:
2375:
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2258:
2251:
2229:
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2218:
2200:
2196:
2189:
2171:
2167:
2140:
2136:
2129:
2111:
2107:
2097:
2095:
2087:
2086:
2082:
2075:
2061:
2057:
2041:
2035:
2031:
2021:
2019:
2014:
2013:
2009:
1986:
1982:
1966:
1960:
1956:
1946:
1944:
1940:
1934:
1930:
1914:
1908:
1904:
1899:
1895:
1879:
1873:
1856:
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1834:
1827:
1795:
1791:
1762:
1751:
1708:
1704:
1662:
1655:
1639:
1633:
1629:
1614:
1610:
1603:
1587:
1583:
1541:
1533:Chesley, J.T.;
1531:
1502:
1475:
1468:
1452:
1446:
1442:
1430:
1424:
1420:
1410:
1408:
1400:
1394:
1390:
1383:
1382:978-1-899383894
1369:
1360:
1333:
1329:
1324:
1320:
1293:
1280:
1265:
1261:
1257:
1246:
1244:
1243:
1242:
1241:
1235:
1233:
1232:
1231:
1230:
1187:
1174:English Channel
1111:
1108:
1107:
1106:
1104:
1099:
1096:
1095:
1094:
1092:
982:
957:
910:(tin ore) from
901:
825:
810:
808:
807:
806:
805:
799:
797:
796:
795:
794:
692:
660:
583:alkali feldspar
566:
561:
537:
528:
522:
505:
503:Isles of Scilly
491:
482:
465:
456:
447:
427:alkali feldspar
423:
412:The individual
367:
331:
288:
260:metasedimentary
248:partial melting
208:
137:
86:Isles of Scilly
38:Bouguer anomaly
17:
12:
11:
5:
2540:
2530:
2529:
2524:
2519:
2514:
2509:
2504:
2458:
2457:
2442:
2436:
2435:
2421:
2405:
2404:External links
2402:
2401:
2400:
2394:
2379:
2376:
2374:
2373:
2362:(6): 573–591.
2346:
2335:
2320:
2314:978-0118800747
2313:
2307:. p. 99.
2291:
2256:
2249:
2223:
2216:
2194:
2188:978-0118800747
2187:
2165:
2134:
2128:978-0118800747
2127:
2105:
2080:
2073:
2055:
2029:
2007:
1996:(3): 193–203.
1980:
1954:
1928:
1902:
1893:
1854:
1825:
1806:(3): 329–367.
1789:
1776:(3): 203–244.
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1702:
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1627:
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1601:
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1500:
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1358:
1327:
1318:
1307:(3): 525–528.
1278:
1258:
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1245:
1234:
1204:meteoric water
1186:
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1142:
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1121:
1120:
1109:
1097:
1073:
1069:
1068:
1001:
986:mineralization
981:
978:
912:Botallack Mine
900:
897:
824:
821:
817:peraluminosity
809:
798:
691:
688:
659:
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560:
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533:
524:Main article:
521:
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464:
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422:
419:
389:on Bodmin Moor
366:
363:
330:
327:
319:St. Cyres beds
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207:
204:
153:intrusive rock
136:
133:
129:Medieval Latin
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1575:2027.42/30898
1571:
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1535:Halliday A.N.
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1463:(2): 122–131.
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905:
896:
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886:
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872:
870:
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858:
854:
850:
847:developed in
846:
842:
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834:
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792:
787:
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653:
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637:
635:
631:
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623:
619:
614:
610:
602:
601:tourmalinized
598:
594:
587:
584:
579:
570:
556:
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541:
532:
527:
517:
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300:Carboniferous
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261:
257:
253:
250:of the lower
249:
245:
241:
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233:
229:
225:
221:
220:Early Permian
212:
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201:
197:
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99:
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92:particularly
91:
87:
83:
79:
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71:
67:
63:
62:Great Britain
59:
55:
51:
47:
39:
36:
32:
28:
23:
19:
2478:50.2°N 5.2°W
2459:
2445:
2432:Devon portal
2385:
2359:
2355:
2323:
2300:
2294:
2269:
2265:
2259:
2234:
2226:
2207:
2197:
2174:
2168:
2154:(1): 37–41.
2151:
2147:
2137:
2114:
2108:
2096:. Retrieved
2092:
2083:
2064:
2058:
2049:
2045:
2032:
2020:. Retrieved
2010:
1993:
1989:
1983:
1974:
1970:
1957:
1945:. Retrieved
1943:. p. 14
1931:
1922:
1918:
1905:
1896:
1887:
1883:
1848:
1844:
1803:
1799:
1792:
1773:
1769:
1715:
1705:
1670:
1666:
1647:
1643:
1630:
1621:
1611:
1591:
1584:
1549:
1545:
1486:
1482:
1460:
1456:
1443:
1434:
1421:
1409:. Retrieved
1404:
1391:
1372:
1344:
1340:
1330:
1321:
1304:
1300:
1272:
1262:
1196:
1132:-tourmaline-
1017:metasomatism
983:
958:
885:metasomatism
873:
826:
788:
772:
696:peraluminous
693:
684:luxullianite
661:
644:
638:
606:
597:Luxullianite
542:
538:
529:
514:
492:
483:
474:petrographic
466:
463:Carnmenellis
457:
448:
424:
411:
359:
347:country rock
332:
323:
312:
289:
272:
264:metavolcanic
217:
180:
146:
124:
122:
104:and ores of
96:, an ore of
78:Carnmenellis
45:
43:
18:
2481: /
2098:15 December
1735:10871/25924
1688:10871/21771
1085:cassiterite
1083:. Veins of
1041:vesuvianite
1009:metabasalts
994:radioactive
949:in progress
908:Cassiterite
869:plagioclase
861:greenstones
634:phenocrysts
470:Rosemanowes
445:Bodmin Moor
385:Granite at
377:on Dartmoor
373:Granite at
308:Westphalian
296:sedimentary
268:Proterozoic
196:laccolithic
191:Martin Bott
94:cassiterite
70:Bodmin Moor
2496:Categories
2483:50.2; -5.2
2022:17 January
1977:: 344–349.
1947:10 January
1925:: 152–157.
1890:: 116–120.
1650:: 333–339.
1411:17 January
1347:(5): 795.
1255:References
1215:Cretaceous
1211:weathering
1199:china clay
1185:China clay
1117:Muscovites
1089:wolframite
1081:tourmaline
1033:amphiboles
953:See also:
865:hornblende
849:calcareous
760:greywackes
744:phosphorus
680:tourmaline
658:Mineralogy
630:pegmatitic
586:megacrysts
545:pegmatites
489:Land's End
454:St Austell
430:megacrysts
266:rocks, of
200:lopolithic
102:china clay
82:Land's End
74:St Austell
1820:0169-1368
1744:0024-4937
1697:0024-4937
1673:: 76–94.
1208:supergene
1136:-sulfide-
1037:malayaite
1013:exoskarns
881:Potassium
853:amphibole
837:amphibole
784:xenoliths
724:germanium
690:Chemistry
668:muscovite
652:protolith
643:as being
520:Haig Fras
387:Rough Tor
343:diapirism
306:to lower
244:strontium
240:neodymium
206:Formation
183:batholith
178:granite.
176:Haig Fras
149:batholith
27:Haig Fras
2448:(2002),
1851:: 37–41.
1251:ratios.
1219:Cenozoic
1178:Triassic
1138:fluorite
1134:chlorite
1115:fluids.
1045:siderite
1025:pyroxene
970:alluvium
927:Camborne
876:volatile
857:pyroxene
841:pyroxene
833:hornfels
778:against
752:scandium
740:thallium
736:tungsten
732:tantalum
728:rubidium
716:fluorine
622:feldspar
496:xenotime
439:Monazite
421:Dartmoor
357:feeder.
304:Namurian
232:orogenic
165:magnetic
159:). From
125:Cornubia
118:tungsten
90:minerals
84:and the
66:Dartmoor
54:Cornwall
2522:Granite
2466:50°12′N
2378:Sources
2274:Bibcode
1554:Bibcode
1172:to the
1154:uranium
1077:greisen
1065:arsenic
1049:axinite
1029:epidote
961:mineral
935:St. Day
931:Redruth
916:St Just
893:greisen
871:rocks.
780:yttrium
730:, tin,
720:gallium
712:uranium
708:caesium
700:lithium
672:biotite
626:biotite
609:granite
603:granite
564:Granite
549:aplites
414:plutons
365:Plutons
339:stoping
275:Celsius
187:plutons
161:gravity
50:granite
2469:5°12′W
2392:
2311:
2247:
2214:
2185:
2125:
2071:
1818:
1742:
1716:Lithos
1695:
1667:Lithos
1599:
1379:
1166:brines
1158:barite
1150:silver
1130:quartz
1057:copper
1021:garnet
1005:shales
990:gangue
959:Large
889:sodium
845:Garnet
776:cerium
766:of 50
748:barium
645:S-type
618:quartz
553:elvans
375:Haytor
315:clasts
286:Timing
256:mantle
127:, the
106:copper
2454:Vol 2
2450:Vol 1
2042:(PDF)
1967:(PDF)
1941:(PDF)
1915:(PDF)
1880:(PDF)
1841:(PDF)
1640:(PDF)
1542:(PDF)
1453:(PDF)
1431:(PDF)
1401:(PDF)
974:lodes
966:veins
704:boron
613:magma
252:crust
157:magma
58:Devon
2452:and
2390:ISBN
2309:ISBN
2245:ISBN
2212:ISBN
2183:ISBN
2123:ISBN
2100:2016
2069:ISBN
2024:2011
1949:2011
1816:ISSN
1740:ISSN
1693:ISSN
1597:ISBN
1413:2011
1377:ISBN
1229:and
1152:and
1079:and
1063:and
1061:iron
1047:and
1007:and
855:and
756:zinc
738:and
710:and
670:and
664:mica
624:and
599:, a
551:and
355:dyke
351:sill
280:Tors
262:and
242:and
163:and
116:and
114:zinc
110:lead
56:and
44:The
35:mGal
2364:doi
2360:133
2282:doi
2241:447
2156:doi
2152:145
1998:doi
1808:doi
1778:doi
1730:hdl
1720:doi
1683:hdl
1675:doi
1671:260
1570:hdl
1562:doi
1491:doi
1487:150
1349:doi
1345:151
1309:doi
1305:164
1217:to
1053:tin
791:ppm
768:MPa
754:to
674:).
437:of
198:or
98:tin
2498::
2358:.
2354:.
2280:.
2270:65
2268:.
2243:.
2206:.
2150:.
2146:.
2091:.
2050:10
2048:.
2044:.
1994:99
1992:.
1973:.
1969:.
1921:.
1917:.
1886:.
1882:.
1857:^
1849:10
1847:.
1843:.
1828:^
1814:.
1804:28
1802:.
1774:56
1772:.
1768:.
1752:^
1738:.
1728:.
1714:.
1691:.
1681:.
1669:.
1656:^
1646:.
1642:.
1620:.
1568:.
1560:.
1550:57
1548:.
1544:.
1503:^
1485:.
1481:.
1469:^
1459:.
1455:.
1433:.
1403:.
1361:^
1343:.
1339:.
1303:.
1299:.
1281:^
1105:CO
1093:CO
1059:,
1055:,
1043:,
1039:,
1035:,
1027:,
1023:,
914:,
839:,
813:Sr
802:Sr
786:.
770:.
734:,
726:,
722:,
718:,
706:,
702:,
676:Li
654:.
620:,
555:.
547:,
341:,
224:Ma
147:A
120:.
112:,
108:,
80:,
76:,
72:,
68:,
2456:.
2398:.
2370:.
2366::
2350:O
2341:/
2339:O
2317:.
2288:.
2284::
2276::
2253:.
2220:.
2191:.
2162:.
2158::
2131:.
2102:.
2077:.
2052:.
2026:.
2004:.
2000::
1975:7
1951:.
1923:7
1888:5
1822:.
1810::
1786:.
1780::
1746:.
1732::
1722::
1699:.
1685::
1677::
1648:9
1624:.
1605:.
1578:.
1572::
1564::
1556::
1497:.
1493::
1461:2
1415:.
1385:.
1355:.
1351::
1315:.
1311::
1249:O
1240:/
1238:O
1227:H
1225:/
1223:D
1110:2
1098:2
933:-
929:-
883:–
867:-
804:/
40:.
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