Mo-related Adakitic Granitoids from Non-island-arc Setting: Jecheon Pluton of South Korea

Ishihara, Shunsō; Jin, Myung Shik; Terashima, Shigeru

doi:10.1111/j.1751-3928.2005.tb00259.x

Cited by 15 publications

(11 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Recently, other origins of adakite have been proposed, such as partial melting of thick lower continental crust or delaminated lower continental crust (e.g. Atherton & Petford, 1993; Kay & Kay, 1993; Muir et al ., 1995; Defant et al ., 2002; Ishihara, 2005; Ishihara et al ., 2005). Kamei (2002) suggested that adakitic rocks can be produced by an anatexis of metaluminous tonalite to granodiorite.…”

Section: Considerationsmentioning

confidence: 99%

“…Judging from the Sr/Y vs. Y diagram and the REE patterns, almost all the Daebo granitic rocks plot in the field of adakitic rocks, but almost all belong to the ilmenite series. These characteristics are different from the original adakite of the magnetite series, derived from partial melting of subducted oceanic crust (Ishihara et al ., 2005). On the basis of Sr–Nd isotope analysis, Jwa (2004) concluded that the source material of the Daebo granitic rocks was continental crust.…”

Section: Considerationsmentioning

confidence: 99%

See 1 more Smart Citation

Petrogenesis and Solidification Depth of the Jurassic Daebo and Cretaceous Bulguksa Granitic Rocks in South Korea

et al. 2012

View full text Add to dashboard Cite

We investigated the Jurassic Daebo and Cretaceous Bulguksa granitic rocks in South Korea. The former are distributed mainly in the Gyeonggi and Yeongnam massifs and the latter are present in the Gyeongsan basin and Ogcheon belt. The Daebo granitic rocks generally are of ilmenite series and I to S type. These rocks are associated with Au-Ag hydrothermal deposits, whereas the Bulguksa granitic rocks are of magnetite series and I type, and are associated with Pb-Zn, Cu and Mo-W hydrothermal deposits, as well as Au-Ag hydrothermal deposits. The Daebo granitic rocks show adakitic signatures in their chemical compositions. They are considered to have been derived from partial melting of the thick lower continental crust. Conversely, the Bulguksa granitic rocks in the Gyeongsan basin are non-adakitic and are considered to have been derived from partial melting of a mantle wedge. Magmas of the Daebo granitic rocks formed at relatively shallow levels, but solidified at deep levels compared with those of the Bulguksa granitic rocks. The Bulguksa granitic rocks in the central to western Ogcheon belt are considered to have been formed by fractionation of magmas derived from partial melting of continental crust. The total Al contents of biotite and hornblende in the granitic rocks increased, with the Bulguksa granitic rocks in the Gyeongsan basin < the Bulguksa granitic rocks in the Ogcheon belt and Gyeonggi and Yeongnam massifs and the Daebo granitic rocks in the Ogcheon belt < the Daebo granitic rocks in the Gyeonggi and Yeongnam massifs. This order corresponds to an increase in solidification depth.

show abstract

Section: Considerationsmentioning

confidence: 99%

Section: Considerationsmentioning

confidence: 99%

Petrogenesis and Solidification Depth of the Jurassic Daebo and Cretaceous Bulguksa Granitic Rocks in South Korea

et al. 2012

View full text Add to dashboard Cite

show abstract

“…As mentioned previously, the studied plutonic rocks are free of magnetite and have hornblende-biotite and / or biotite assemblages, except for the Busetsu Granites of the Okazaki-Inabu zone, which has (garnet-)muscovite-biotite or biotite assemblage. The granitoids are non-adakitic (Sr / Y < 22, Ishihara et al, 2005), but a few high Sr / Y values are observed in the Shinshiro-Shitara zone (e.g., Nos. 4 and 12), and the Okazaki-Busetsu zone (Nos.…”

Section: Variation Diagrams For the Granitoidsmentioning

confidence: 99%

Chemical compositions of the late Cretaceous Ryoke granitoids of the Chubu District, central Japan – Revisited

Ishihara¹

2007

Bull. Geol. Surv. Japan

Self Cite

View full text Add to dashboard Cite

Late Cretaceous plutonic rocks of 6 gabbroids, and 75 granitoids, all belonging to ilmenite series, were re-examined by polarized XRF method. The gabbroids are relatively abundant in the south of the studied region, implying more in-put of heat and mafic magmas from the upper mantle to the lower crust. The MgO/Fe2O3 ratio of the gabbroids reveal regional variation being MgO-rich to the south, which would reflect generation depth of the mafic magmas. The granitoids are classified into I type and S type. The I-type granitoids occur most widely and divided into five zones. Their average silica contents vary from the Median Tectonic Line to the north as follows: Shinshiro-Shitara zone (60.1 % SiO2), Asuke zone (64.2 %), Toyota-Akechi zone (70.0 %), Sanagesan-Obara zone (73.9 %) and Seto zone (75.2 %). This regional variation was considered to reflect chemical heterogeneity of the infracrustal source rocks, rather than the magmatic differentiation.Granitoids of the Okazaki-Busetsu zone, represented by garnet-bearing muscovite-biotite granites, occur in the highest metamorphic grade zone, and is felsic (average SiO2 70.2 %), peraluminous (A/CNK over 1.1), and thus be called S type. Because of the highest heat flow rate in the OkazakiBusetsu zone, even supracrustal rocks were converted to magmas and formed the S-type granites. Both I and S type granitoids are often heterogeneous in the foliated parts, as compared with massive granitoids of non-metamorphic terrains. The heterogeneity can be considered due to different original compositions of the source materials and/or formed by differential regional stress during the flow movement of the solidifying magmas. Lack of hydrothermal mineralization in the south where metamorphic roof-pendent still remain, can be explained by a deep emplacement level ( 15 km) and small degree of fractionation of these granitic magmas.

show abstract

“…In Korea, the largest Jecheon Mo skarn deposit (Kim & Hwang, ) occurs at the southern margin of pink biotite granite of the magnetite series, Jurassic in age, which is adakitic (Ishihara et al ., ). In the Japanese Islands, major Mo‐deposits are vein type in the magnetite‐series granitic terrane, but stockwork‐type deposits hosted in granitic porphyry dike and plug are present in the center of Pb–Zn skarn deposits of Nakatatsu and Kamioka deposit within the Sanin Eocene Mo‐province of the Inner Zone of SW Japan (e.g., Ishihara, ).…”

Section: Discrimination Of Magnetite/ilmenite‐series Granitoidsmentioning

confidence: 97%

Some Pertinent Features of Mo‐Mineralized Granitoids in the Circum‐Pacific Region

Ishihara

Qing

2014

Resource Geology

Self Cite

View full text Add to dashboard Cite

Petrological characteristics of granitic rocks related to the world large molybdenum deposits are studied. The granitoids are evaluated by Fe2O3+TiO2-FeO+MnO-MgO diagrams, and found to all plot to the magnetite-series field. They are all high silica and high-K series, but not A-type, except for the Climax-type porphyries and some others in the Colorado mineral belt. By-product molybdenum contained in porphyry copper deposits, lower grade but huge tonnage, occurs with calc-alkaline I-type magnetite-series granodiorite and monzogranite.Felsic intrusive rocks of the Climax mine are A-type and are exceptionally high in trace elements such as F and Rb, which are generally enriched with W and Sn-related granitoids that originated in crustal source rocks. The by-product molybdenites in porphyry copper deposits appear to originate in adakitic granodiorite or monzogranite, having deep origins with the subducted slab or thickened juvenile mafic lower crust. Therefore, there is no single magma type but the magnetite series, which concentrates a large volume of molybdenum in the ore deposits.

show abstract

Mo-related Adakitic Granitoids from Non-island-arc Setting: Jecheon Pluton of South Korea

Cited by 15 publications

References 33 publications

Petrogenesis and Solidification Depth of the Jurassic Daebo and Cretaceous Bulguksa Granitic Rocks in South Korea

Petrogenesis and Solidification Depth of the Jurassic Daebo and Cretaceous Bulguksa Granitic Rocks in South Korea

Chemical compositions of the late Cretaceous Ryoke granitoids of the Chubu District, central Japan – Revisited

Some Pertinent Features of Mo‐Mineralized Granitoids in the Circum‐Pacific Region

Contact Info

Product

Resources

About