Cenozoic volcanic arc history of East Java, Indonesia: The stratigraphic record of eruptions on an active continental margin

The Late Triassic Tumugou Formation volcanic rocks which belongs to typical island arc volcanic rocks in southern end of Yidun island arc belt is located at the eastern of the Zhongdian ,NW Yunnan, SW China. The volcanic rocks can be divided into three categories:andesitic basalt, andesite, quartz andesite, etc. Through geochemical analysis the major elements, rare earth ele and trace element in volcanic rocks, SiO255.18-57.59×10-2,TiO21.16-1.45×10-2,Na2O+K2O5.11-8.05×10-2.consider it is calc-alkaline- alkaline Series of high-K andesite, volcanic may be controlled by the crystal fractionation of magma.Rb31.50-101×10-6,Ba1310-12300×10-6,Nb/Ta11.4-15.5,REE166.07-240.78×10-6,δEu0.74-1.00,REE distribution patterns show oblique to the HREE side and enrichment in LREE .Eu anomaly is not obvious. It is can see from the relevant figure about trace element, it is very similar in magmatic distribution patterns between volcanic rock and Volcanic-arc rock, indicating that the volcanic in this area may be formed in volcanic-arc environment. From east to west, Magma source depth have regular change with the really thickness of mainland shell. Explain that Tumugou Formation volcanic rock is subduction by Ganzi- Litang Ocean basin from east to west. Hongshan-Ousaila region of eastern edge of Zhongdian is the volcanic island arc system during the passive continental margin into an active continental margin.

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Age and significance of radiolarian sediments within basic extrusives of the marginal basin Guevgueli Ophiolite (northern Greece)

Geological Magazine ◽

10.1017/s0016756800008645 ◽

1996 ◽

Vol 133 (2) ◽

pp. 127-136 ◽

Cited By ~ 27

Author(s):

Taniel Danelian ◽

Alastair H. F. Robertson ◽

Sarantis Dimitriadis

Keyword(s):

Continental Margin ◽

Late Jurassic ◽

Active Continental Margin ◽

Volcanic Glass ◽

Northern Greece ◽

The West ◽

Volcanic Arc ◽

Marginal Basin ◽

Radiolarian Assemblage ◽

Early Late

AbstractWell-preserved Radiolaria have been discovered in calcareous silt turbidites and mudstones intercalated with basic extrusives of the Guevgueli Ophiolite, northern Greece. The mudstones contain terrigenous silt, probably derived from adjacent continental basement of the Serbo-Macedonian and/or Paikon units. Volcanic quartz and rare volcanic glass were probably derived from an active continental margin arc (Paikon volcanic arc) to the west. The radiolarian sediments were deposited within fault-controlled hollows in the ophiolitic extrusives, and then covered by massive and pillowed extrusives. The radiolarian assemblage is indicative of an early Late Jurassic (Oxfordian) age, which therefore dates the genesis of the Guevgueli Ophiolite. Our data are consistent with the age of the intrusive Late Jurassic Fanos Granite, believed to be contemporaneous with the Guevgueli Ophiolite. In general, the Guevgueli and related ophiolites of northern Greece are thought to have formed within a transtensional intra-continental marginal basin, generated in response to oblique eastward subduction of older Tethyan oceanic crust (Almopias ocean).

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U-Pb (zircon) age for the Beaver Harbour Porphyry, New River belt, southern New Brunswick, Canada

Atlantic Geology ◽

10.4138/atlgeol.2014.010 ◽

2014 ◽

Vol 50 ◽

pp. 155

Author(s):

Sandra M. Barr ◽

Cameron J. Bartsch ◽

Brent V. Miller ◽

Chris E. White

Keyword(s):

New Brunswick ◽

Continental Margin ◽

Active Continental Margin ◽

Chemical Data ◽

Volcanic Arc ◽

Zircon Age ◽

Isotopic Signatures ◽

Southern Margin ◽

High Level

The Beaver Harbour Porphyry is a high-level intermediate to felsic granitoid and locally tuffaceous unit with quartz and less abundant feldspar phenocrysts. It forms a fault-bound sliver along the southern margin of the New River belt in southern New Brunswick. A concordant TIMS U-Pb (zircon) age of 551 ± 1.2 Ma shows that the porphyry is of the same age as other high-level plutonic and volcanic units that form most of the New River belt. Chemical data show that these units likely formed in a volcanic-arc environment at an active continental margin. One sample from the porphyry has ƐNd(t) of -0.5, within the range of other samples from the New River belt and consistent with the interpretation that the belt is part of Ganderia, rather than Avalonia, which generally has more juvenile isotopic signatures.

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Uplift history of a transform continental margin revealed by the stratigraphic record: The case of the Agulhas transform margin along the Southern African Plateau

Tectonophysics ◽

10.1016/j.tecto.2018.03.014 ◽

2018 ◽

Vol 731-732 ◽

pp. 104-130 ◽

Cited By ~ 15

Author(s):

Guillaume Baby ◽

François Guillocheau ◽

Carl Boulogne ◽

Cécile Robin ◽

Massimo Dall'Asta

Keyword(s):

Continental Margin ◽

Stratigraphic Record ◽

History Of ◽

Uplift History ◽

Transform Margin

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Identification of prospective geosites that show features of the active continental margin in eastern Kii Peninsula, Southwest Japan

Acta Geoturistica ◽

10.1515/agta-2017-0003 ◽

2017 ◽

Vol 8 (1) ◽

pp. 19-31

Author(s):

Dorota Suzuki ◽

Hideo Takagi

Keyword(s):

Continental Margin ◽

Active Continental Margin ◽

Southwest Japan ◽

Rock Outcrops ◽

Kii Peninsula ◽

Geological Features ◽

Relative Value ◽

Formation History ◽

History Of ◽

Japanese Islands

AbstractThe eastern Kii Peninsula exhibits a variety of rock outcrops, fossils, and other geological features that illustrate the formation history of the Japanese Islands. This work aims to describe the geotourism potential of the region based on the significant rock exposures, and sets out the basis for establishing geosites in this region in the future. Geologically important sites have been selected, together with places of unique history and culture within the northern part of the eastern Kii Peninsula, including the Ise and Toba areas. The results of this study include a detailed description of the geology and history of the region, together with an evaluation of the relative value of each selected locality as a geosite. Proper development and promotion of the proposed sites would make the sites available for education and tourism, and provide opportunities for suitable development and the popularization of geological knowledge.

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Growth and Shrinkage of an Active Continental Margin: Updated Geotectonic History of the Japanese Islands

Journal of Geography (Chigaku Zasshi) ◽

10.5026/jgeography.120.65 ◽

2011 ◽

Vol 120 (1) ◽

pp. 65-99 ◽

Cited By ~ 35

Author(s):

Yukio ISOZAKI ◽

Shigenori MARUYAMA ◽

Takaaki NAKAMA ◽

Shinji YAMAMOTO ◽

Shuichi YANAI

Keyword(s):

Continental Margin ◽

Active Continental Margin ◽

History Of ◽

Japanese Islands

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The Vendian-Early Paleozoic History of the Continental Margin of Eastern Paleogondwana, Paleoasian Ocean, and Central Asian Foldbelt

Russian Journal of Earth Sciences ◽

10.2205/2003es000123 ◽

2003 ◽

Vol 5 (3) ◽

pp. 165-184 ◽

Cited By ~ 103

Author(s):

T. N. Kheraskova ◽

Yu. A. Volozh ◽

A. N. Didenko ◽

V. A. Bush

Keyword(s):

Continental Margin ◽

Early Paleozoic ◽

Paleoasian Ocean ◽

Central Asian ◽

History Of

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Nature and origin of the volcanic ash beds near the Permian–Triassic boundary in South China: new data and their geological implications

Geological Magazine ◽

10.1017/s001675681900133x ◽

2019 ◽

Vol 157 (4) ◽

pp. 677-689 ◽

Cited By ~ 3

Author(s):

Binsong Zheng ◽

Chuanlong Mou ◽

Renjie Zhou ◽

Xiuping Wang ◽

Zhaohui Xiao ◽

...

Keyword(s):

Trace Element ◽

Continental Margin ◽

South China ◽

Volcanic Ash ◽

Active Continental Margin ◽

Main Body ◽

Early Triassic ◽

Late Permian ◽

Triassic Boundary ◽

Permian Triassic Boundary

AbstractPermian–Triassic boundary (PTB) volcanic ash beds are widely distributed in South China and were proposed to have a connection with the PTB mass extinction and the assemblage of Pangea. However, their source and tectonic affinity have been highly debated. We present zircon U–Pb ages, trace-element and Hf isotopic data on three new-found PTB volcanic ash beds in the western Hubei area, South China. Laser ablation inductively coupled plasma mass spectrometry U–Pb dating of zircons yields ages of 252.2 ± 3.6 Ma, 251.6 ± 4.9 Ma and 250.4 ± 2.4 Ma for these three volcanic ash beds. Zircons of age c. 240–270 Ma zircons have negative εHf(t) values (–18.17 to –3.91) and Mesoproterozoic–Palaeoproterozoic two-stage Hf model ages (THf2) (1.33–2.23 Ga). Integrated with other PTB ash beds in South China, zircon trace-element signatures and Hf isotopes indicate that they were likely sourced from intermediate to felsic volcanic centres along the Simao–Indochina convergent continental margin. The Qinling convergent continental margin might be another possible source but needs further investigation. Our data support the model that strong convergent margin volcanism took place around South China during late Permian – Early Triassic time, especially in the Simao–Indochina active continental margin and possibly the Qinling active continental margin. These volcanisms overlap temporally with the PTB biocrisis triggered by the Siberian Large Igneous Province. In addition, our data argue that the South China Craton and the Simao–Indochina block had not been amalgamated with the main body of Pangea by late Permian – Early Triassic time.

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