scholarly journals Granite-Related Tin Metallogenic Events and Key Controlling Factors in Peninsular Malaysia, Southeast Asia: New Insights from Cassiterite U-Pb Dating and Zircon Geochemistry

2020 ◽  
Vol 115 (3) ◽  
pp. 581-601 ◽  
Author(s):  
Jie-Hua Yang ◽  
Mei-Fu Zhou ◽  
Rui-Zhong Hu ◽  
Hong Zhong ◽  
Anthony E. Williams-Jones ◽  
...  
Keyword(s):  
Trace Elements ◽  
Sedimentary Rock ◽  
Continental Collision ◽  
Peninsular Malaysia ◽  
Controlling Factors ◽  
Low Oxygen ◽  
Redox States ◽  
Magma Sources ◽  
Tin Deposits ◽  
T Values

Abstract Permian-Triassic granites and associated tin deposits are widespread in the Eastern and Western belts of Peninsular Malaysia. The ages and key controlling factors of tin mineralization, however, are poorly constrained. Cassiterite separates from the Sintok and Rahman tin deposits in the Western belt, and Bandi, Setahum, Lembing, and Cherul tin deposits in the Eastern belt have U-Pb ages of 218.9 ± 3.4 and 226.8 ± 7.6 Ma, and 213.1 ± 3.9, 270.6 ± 4.6, 282.7 ± 4.6, and 281.3 ± 3.5 Ma, respectively. These ages directly constrain the tin mineralization in Peninsular Malaysia to two separate periods: 290 to 270 Ma and 230 to 210 Ma. Zircon crystals from tin-bearing granites in the Cherul and Sintok deposits have U-Pb ages of 276.0 ± 1.9 and 221.9 ± 0.6 Ma, respectively, consistent with the cassiterite U-Pb ages within uncertainties. Zircon crystals from barren granites of the Kuantan pluton in the Eastern belt have a U-Pb age of 260.5 ± 0.7 Ma, which is between the two tin mineralization periods. Zircon from these barren granites have εHf(t) values from −5.4 to 3.6, two-stage Hf model ages (TDM2) from 1.4 to 1.0 Ga, and Ce4+/Ce3+ ratios from 40 to 120. By comparison, zircon crystals from the tin-bearing granites have low εHf(t) values (−9.7 to −3.2) and Ce4+/Ce3+ ratios (4–67) and high TDM2 (1.8–1.4 Ga). Zircon ages, Hf isotopes, and trace elements indicate that the tin-bearing granitic magmas in Peninsular Malaysia had relatively low oxygen fugacity and were derived from reworking of Paleo- to Mesoproterozoic sedimentary rock-dominated crust in response to the Paleo-Tethyan subduction and continental collision. This study confirms that the nature of magma sources and redox states of magmas were key in the formation of the tin-rich granites and associated tin deposits and that the granite-related tin mineralization in Peninsular Malaysia was closely related to the evolution of the eastern Paleo-Tethys.

Tectonic transition from oceanic subduction to continental collision: New geochemical evidence from Early-Middle Triassic mafic igneous rocks in southern Liaodong Peninsula, east-central China

2019 ◽  
Vol 132 (7-8) ◽  
pp. 1469-1488 ◽  
Author(s):  
Wei Fang ◽  
Li-Qun Dai ◽  
Yong-Fei Zheng ◽  
Zi-Fu Zhao ◽  
Li-Tao Ma
Keyword(s):  
Trace Elements ◽  
Middle Triassic ◽  
Continental Collision ◽  
Igneous Rocks ◽  
Central China ◽  
East Central ◽  
Mafic Rocks ◽  
Tectonic Transition ◽  
T Values ◽  
Early Middle Triassic

Abstract In contrast to the widespread occurrence of mafic arc magmatism during oceanic subduction, there is a general lack of such magmatism during continental subduction. This paradigm is challenged by the discovery of Early-Middle Triassic mafic igneous rocks from the southeastern margin of the North China Block (NCB), which was subducted by the South China Block (SCB) during the Triassic. Zircon U-Pb dating for these mafic rocks yields 247 ± 2–244 ± 5 Ma for their emplacement, coeval with the initial collision between the two continental blocks. These Triassic mafic rocks generally exhibit ocean island basalt (OIB)-like trace element distribution patterns, intermediate (87Sr/86Sr)i ratios of 0.7057–0.7091, weakly negative εNd(t) values of –1.2 to –3.8, and εHf(t) values of –1.3 to –3.2. Such geochemical features indicate origination from a metasomatic mantle source with involvement of felsic melts derived from dehydration melting of the previously subducting Paleo-Tethyan oceanic crust. The syn-magmatic zircons of Triassic age show variable Hf-O isotopic compositions, indicating that the crustal component was composed of both altered basaltic oceanic crust and terrigenous sediment. High Fe/Mn and Zn/Fe ratios suggest that the mantle source would mainly consist of ultramafic pyroxenites. The melt-mobile incompatible trace elements were further fractionated relative to melt-immobile trace elements during partial melting of these pyroxenites, giving rise to basaltic melts with OIB-like geochemical signatures. The mafic magmatism may be caused by tectonic extension due to rollback of the subducting Paleo-Tethyan oceanic slab in response to the initial collision of the NCB and SCB in the Early Triassic. Therefore, the syn-subduction mafic magmatism provides new geochemical evidence for tectonic transition from oceanic subduction to continental collision in east-central China.

Origin of syn-collisional granitoids in the Gangdese orogen: Reworking of the juvenile arc crust and the ancient continental crust

2021 ◽  
Author(s):  
Yu-Wei Tang ◽  
Long Chen ◽  
Zi-Fu Zhao ◽  
Yong-Fei Zheng
Keyword(s):  
Partial Melting ◽  
Continental Crust ◽  
Continental Collision ◽  
Late Eocene ◽  
Igneous Rocks ◽  
Early Eocene ◽  
Southern Tibet ◽  
Crustal Rocks ◽  
Mafic Magmas ◽  
T Values

Granitoids at convergent plate boundaries can be produced either by partial melting of crustal rocks (either continental or oceanic) or by fractional crystallization of mantle-derived mafic magmas. Whereas granitoid formation through partial melting of the continental crust results in reworking of the pre-existing continental crust, granitoid formation through either partial melting of the oceanic crust or fractional crystallization of the mafic magmas leads to growth of the continental crust. This category is primarily based on the radiogenic Nd isotope compositions of crustal rocks; positive εNd(t) values indicate juvenile crust whereas negative εNd(t) values indicate ancient crust. Positive εNd(t) values are common for syn-collisional granitoids in southern Tibet, which leads to the hypothesis that continental collision zones are important sites for the net growth of continental crust. This hypothesis is examined through an integrated study of in situ zircon U-Pb ages and Hf isotopes, whole-rock major trace elements, and Sr-Nd-Hf isotopes as well as mineral O isotopes for felsic igneous rocks of Eocene ages from the Gangdese orogen in southern Tibet. The results show that these rocks can be divided into two groups according to their emplacement ages and geochemical features. The first group is less granitic with lower SiO2 contents of 59.82−64.41 wt%, and it was emplaced at 50−48 Ma in the early Eocene. The second group is more granitic with higher SiO2 contents of 63.93−68.81 wt%, and it was emplaced at 42 Ma in the late Eocene. The early Eocene granitoids exhibit relatively depleted whole-rock Sr-Nd-Hf isotope compositions with low (87Sr/86Sr)i ratios of 0.7044−0.7048, positive εNd(t) values of 0.6−3.9, εHf(t) values of 6.5−10.5, zircon εHf(t) values of 1.6−12.1, and zircon δ18O values of 5.28−6.26‰. These isotopic characteristics are quite similar to those of Late Cretaceous mafic arc igneous rocks in the Gangdese orogen, which indicates their derivation from partial melting of the juvenile mafic arc crust. In comparison, the late Eocene granitoids have relatively lower MgO, Fe2O3, Al2O3, and heavy rare earth element (HREE) contents but higher K2O, Rb, Sr, Th, U, Pb contents, Sr/Y, and (La/Yb)N ratios. They also exhibit more enriched whole-rock Sr-Nd-Hf isotope compositions with high (87Sr/86Sr)i ratios of 0.7070−0.7085, negative εNd(t) values of −5.2 to −3.9 and neutral εHf(t) values of 0.9−2.3, and relatively lower zircon εHf(t) values of −2.8−8.0 and slightly higher zircon δ18O values of 6.25−6.68‰. An integrated interpretation of these geochemical features is that both the juvenile arc crust and the ancient continental crust partially melted to produce the late Eocene granitoids. In this regard, the compositional evolution of syn-collisional granitoids from the early to late Eocene indicates a temporal change of their magma sources from the complete juvenile arc crust to a mixture of the juvenile and ancient crust. In either case, the syn-collisional granitoids in the Gangdese orogen are the reworking products of the pre-existing continental crust. Therefore, they do not contribute to crustal growth in the continental collision zone.

Oxygen-Hafnium-Neodymium Isotope Constraints on the Origin of the Talnakh Ultramafic-Mafic Intrusion (Norilsk Province, Russia)

2020 ◽  
Vol 115 (6) ◽  
pp. 1195-1212 ◽  
Author(s):  
Kreshimir N. Malitch ◽  
Elena A. Belousova ◽  
William L. Griffin ◽  
Laure Martin ◽  
Inna Yu. Badanina ◽  
...  
Keyword(s):  
Crustal Contamination ◽  
Ultramafic Rocks ◽  
Magma Chambers ◽  
Nd Isotope ◽  
Crustal Component ◽  
Depleted Mantle ◽  
Magma Sources ◽  
A Minor ◽  
T Values

Abstract The ultramafic-mafic Talnakh intrusion in the Norilsk province (Russia) hosts one of the world’s major platinum group element (PGE)-Cu-Ni sulfide deposits. This study employed a multitechnique approach, including in situ Hf-O isotope analyses of zircon combined with whole-rock Nd isotope data, in order to gain new insights into genesis of the Talnakh economic intrusion. Zircons from gabbrodiorite, gabbroic rocks of the layered series, and ultramafic rocks have similar mantle-like mean δ18O values (5.39 ± 0.49‰, n = 27; 5.64 ± 0.48‰, n = 34; and 5.28 ± 0.34‰, n = 7, respectively), consistent with a mantle-derived origin for the primary magma(s) parental to the Talnakh intrusion. In contrast, a sulfide-bearing taxitic-textured troctolite from the basal part of intrusion has high δ18O (mean of 6.50‰, n = 3), indicating the possible involvement of a crustal component during the formation of sulfide-bearing taxitic-textured rocks. The Hf isotope compositions of zircon from different rocks of the Talnakh intrusion show significant variations, with ɛHf(t) values ranging from –3.2 to 9.8 for gabbrodiorite, from –4.3 to 11.6 for unmineralized layered-sequence gabbroic rocks, from 2.3 to 12 for mineralized ultramafic rocks, and from –3.5 to 8.8 for mineralized taxitic-textured rocks at the base of the intrusion. The significant range in the initial 176Hf/177Hf values is ascribed to interaction of distinct magma sources during formation of the Talnakh intrusion. These include (1) a juvenile source equivalent to the depleted mantle, (2) a subcontinental lithospheric source, and (3) a minor crustal component. Initial whole-rock Nd isotope compositions of the mineralized taxitic-textured rocks from the base of the intrusion (mean ɛNd(t) = –1.5 ± 1.8) differ from the other rocks, which have relatively restricted ranges in initial ɛNd (mean ɛNd = 0.9 ± 0.2). The major set of ɛNd values around 1.0 at Talnakh is attributed to limited crustal contamination, presumably in deep magma chambers, whereas the smaller set of negative ɛNd values in taxitic-textured rocks is consistent with greater involvement of a crustal component and reflects an interaction with the wall rocks during emplacement.

Early Cretaceous Xiuyan adakitic granitoids in the Liaodong Peninsula, eastern China: petrogenesis and implications for lithospheric thinning of the North China Craton

2021 ◽  
Vol 58 (1) ◽  
pp. 50-66
Author(s):  
Yang Dong ◽  
Jingdang Liu ◽  
Yanfei Zhang ◽  
Shiyong Dou ◽  
Yanbin Li ◽  
...  
Keyword(s):  
Early Cretaceous ◽  
North China Craton ◽  
Lower Crust ◽  
North China ◽  
Eastern China ◽  
Lithospheric Thinning ◽  
The North ◽  
Magma Sources ◽  
Liaodong Peninsula ◽  
T Values

Mesozoic magmatic rocks are widely distributed in the North China Craton (NCC) and are crucial to understanding the timing, location, and geodynamic mechanisms of lithospheric thinning of the NCC. In this study, we report geochronological, petrogeochemical, and Lu–Hf isotopic data for adakitic granitoids from different parts of Xiuyan pluton in the Liaodong Peninsula, aiming to constrain their magma sources, petrogenesis, and tectonic implications. The adakites are metaluminous to weakly peraluminous and are classified as high-K calc-alkaline I-type granite with Early Cretaceous zircon U–Pb ages of 129–126 Ma. They exhibit adakite-like geochemical characteristics, such as high Sr content and low Yb and Y contents, coupled with high Sr/Y and no pronounced Eu anomalies. They are enriched in Rb, U, and light rare-earth elements and are depleted in Ta, Nb, P, and Ti. The adakites from the eastern part of the pluton have low εHf(t) values (–8.5 to –4.0) with old TDM2 ages (1.57–1.31 Ga), indicating they were derived from the lower crust containing juvenile mantle-derived materials. In contrast, adakites from the northern part of the pluton have lower εHf(t) values (–19.7 to –16.6) with older TDM2 ages (2.21–2.03 Ga), indicating that they were derived mainly from an ancient crust. Our results show that both adakitic magmas were derived from partial melting of delaminated lower crust. Their relatively high MgO and Ni contents and Mg# values indicate that the melts interacted with mantle peridotites. The lower crust delamination beneath the Liaodong Peninsula resulted from paleo-Pacific plate subduction during the Early Cretaceous, which resulted in thinning of Mesozoic crust in the Xiuyan area.

Mesozoic Intrusive Rocks Characteristics and Comparative between the West Hubei-Jiangxi and the East Jiangsu-Anhui

2012 ◽  
Vol 524-527 ◽  
pp. 144-147
Author(s):  
Cui Xia Qu ◽  
Xing Ke Yang ◽  
Hu Jun He ◽  
Hong Ye Song
Keyword(s):  
Yangtze River ◽  
Controlling Factors ◽  
Project Work ◽  
The West ◽  
Intrusive Rocks ◽  
Magma Sources ◽  
Tectonic Framework ◽  
Lower Yangtze ◽  
Base Structure ◽  
Comprehensive Study

This paper relies on "The base structure and guide the middle and lower Yangtze River mine - re-controlling factors of research project" in order to study the Mesozoic intrusive rocks in the characteristics of the middle and lower Yangtze River area and distribute-on of the western part of Hubei - Jiangxi and eastern Jiangsu - Anhui comparative study of eastern and western areas. On the basis of the full collection and comprehensive study of previous data, with the actual project work and research, through comprehensive research and analysis, bounded on the east and west of Jiujiang area controlled by different tectonic framework of characteristics of intrusive rock, mainly from the petrology, rock chemistry, magma sources and diagenetic characteristics such as age were compared with paper.

scholarly journals On The Supposed Onshore Extension Of The Penyu Basin, Peninsular Malaysia

Warta Geologi ◽  
2021 ◽  
Vol 47 (3) ◽  
pp. 204-210
Author(s):  
Mazlan Madon ◽  
Keyword(s):  
Coastal Plain ◽  
Sedimentary Rock ◽  
Sedimentary Basin ◽  
Peninsular Malaysia ◽  
River Delta ◽  
Metamorphic Rocks ◽  
Quaternary Sediments ◽  
The West

The Penyu Basin is a Tertiary sedimentary basin located offshore Peninsular Malaysia. The basin is assumed to continue westwards beneath the Pahang River delta where as much as 115 m of Quaternary sediments overlie a bedrock of pre-Tertiary granites and metamorphic rocks. No Pliocene or older sediments beneath the delta have been reported. If the Quaternary sediments are considered as part of the Cenozoic Penyu Basin, the basin’s western limit may be delineated at the foothills of the coastal plain where those sediments onlap onto pre-Tertiary rocks. Therefore, any sedimentary rock of Tertiary age that may occur to the west of that limit most probably represents a separate basin.

scholarly journals Geochronological and Geochemical Constraints on the Formation of the Giant Zaozigou Au-Sb Deposit, West Qinling, China

Minerals ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 37 ◽  
Author(s):  
Hao-Cheng Yu ◽  
Chang-An Guo ◽  
Kun-Feng Qiu ◽  
Duncan McIntire ◽  
Gui-Peng Jiang ◽  
...  
Keyword(s):  
Mineral Assemblage ◽  
Spatial Association ◽  
Massive Sulfide ◽  
Stage Model ◽  
Sulfide Mineralization ◽  
Low Oxygen ◽  
Ore Formation ◽  
West Qinling ◽  
T Values ◽  
Geochemical Constraints

The Zaozigou Au-Sb deposit has been controversial in its genesis and remains one of the most difficult ore systems to fully understand in West Qinling. The mineralization shows a broad spatial association with Triassic dikes and sills, which were previously thought to be genetically related to mineralization. Our U-Pb zircon dating in this contribution indicates that the ore-hosting porphyritic dacites were formed at 246.1 ± 5.2 Ma and 248.1 ± 3.8 Ma. The magmatic zircons yield εHf(t) values ranging from −12.5 to −8.9, with corresponding two-stage model ages of 2.08 to 1.83 Ga. The magma therefore could be derived from partial melting of Paleoproterozoic crustal materials. The ore-hosting porphyritic dacites have low oxygen fugacity, with ΔFMQ ranging from −4.61 to −2.56, indicating that magmas could have been sulfide-saturated during evolution in deep chambers and precluding the possibility that metals were released from the melt. Zaozigou exhibits characteristics widespread volcanics, massive sulfide mineralization, rare reduced mineral assemblage and discrete alteration zones which are not typical of reduced intrusion-related or porphyry gold systems. We propose that the spatially-related Triassic porphyritic dacite and dike swarm is not genetically related to the ore formation of Zaozigou Au-Sb deposit.

Oxygen in pore waters of deep-sea sediments

1990 ◽  
Vol 331 (1616) ◽  
pp. 69-84 ◽  
Keyword(s):  
Trace Elements ◽  
Water Depth ◽  
Equatorial Pacific ◽  
Weddell Sea ◽  
Pore Waters ◽  
Low Oxygen ◽  
Sulu Sea ◽  
Manganese Oxyhydroxide ◽  
Low Oxygen Concentration ◽  
Cobalt And Nickel

Profiles of dissolved oxygen are presented from contrasting ocean areas, and compared with data on the distribution of trace elements in sediment and pore water. The release of manganese starts when oxygen is depleted to about 1 pM. In the Sulu Sea (Philippines), the manganese flux to this interface balanced 48+ 16% of the oxygen flux. Large excess 0 2 fluxes in the east Atlantic are attributed to non-steadystate diagenesis. At the transition from 0 2 to manganese reduction, cobalt and nickel are mobilized, and many trace elements, including rare earth elements, undergo a phase transition as a result of the dissolution of the manganese oxyhydroxide carrier phase. In the deep Angola Basin, Weddell Sea and west equatorial Pacific, oxygen penetrates the sediment to well over 1 m. In the semi-enclosed Sulu Sea with a low oxygen concentration in the bottom water (Obw — 55 pm), z0 increases from 1 cm at 1000 m water depth to 10—15 cm at 4000 m, and decreases again to 1 cm in the deepest spots covered by turbidites. Generally, the depth where oxygen is depleted (z0) increases with increasing water depth; z0 decreases at the approach of the continent and under the influence of turbidites ; it increases at topographic highs exposed to winnowing. A model is presented that relates z0 to 0 bw, primary production and water depth. zD is especially sensitive to changes in organic matter input and Obw when oxygen breaks through the bioturbated zone. The large differences in z0 at the same water depth in the Sulu Sea and adjacent South China Sea and west equatorial Pacific (6, 14 and 40 cm at 3500 m depth) can be explained merely by the differences in Obw (55, 105 and 150 pM respectively). It is concluded that glacial to interglacial changes in Obw must have had major effects on diagenesis and infauna throughout the world oceans.

Sign in / Sign up

Export Citation Format

Share Document