scholarly journals The U-Pb zircon age of granodiorite from Dinh Quan Deo Ca complex of Truong Xuan Khanh Hoa area and its geological significance

2015 ◽  
Vol 18 (4) ◽  
pp. 5-11 ◽  
Author(s):  
Hieu Trung Pham
Keyword(s):  
Primary Magma ◽  
Weighted Mean ◽  
Zircon Age ◽  
Geological Significance ◽  
Icp Ms ◽  
Magma Crystallization ◽  
Sr Method

Zircons separated from an granodiorite sample at the Dinh Quan - Deo Ca complex area were dated to determine the protolith age for the complex. Sixteen LA-ICP-MS U-Pb zircon analyses gave concordant ages concentrated at 96 Ma (weighted mean). These results indicated the protolith age of the granodiorite (primary magma crystallization age). The value of this age is close to results analyzed by Rb-Sr method and Ar-Ar method, confirming the crystallization age of the granodiorite Dinh Quan Deo Ca complex corresponding period early Cretaceou.

scholarly journals The LA-ICP-MS U-Pb zircon age of rhyolite from the Dong Trau formation and its geological significances

2018 ◽  
Vol 1 (T5) ◽  
pp. 270-277
Author(s):  
Hieu Trung Pham
Keyword(s):  
Primary Magma ◽  
Early Triassic ◽  
Late Permian ◽  
Weighted Mean ◽  
Zircon Age ◽  
Analytical Results ◽  
Icp Ms ◽  
Magma Crystallization ◽  
Sr Method

Zircons separated from an rhyolite sample in the Dong Trau formation, in the southern of Hà Tĩnh province were dated to determine the protolith age for the complex. Sixteen LA-ICP-MS U-Pb zircon analyses give concordant ages concentrated at 256 Ma (weighted mean). These results indicate the protolith age of the rhyolite (primary magma crystallization age). The value of this age are close to the analytical results pf the whole rock by Rb-Sr method and biotite Rb-Sr method. Therefore the crystallization age of the rhyolite from the Đồng Trầu formation corresponded period late Permian to early Triassic.

scholarly journals 278 Ma U-Pb zircon age of metagranite in Bo Xinh complex area of song Ma structural zone and its significances

2014 ◽  
Vol 17 (4) ◽  
pp. 42-48
Author(s):  
Hieu Trung Pham
Keyword(s):  
Primary Magma ◽  
Early Permian ◽  
Weighted Mean ◽  
Zircon Age ◽  
Mafic Rocks ◽  
Icp Ms ◽  
Magma Crystallization

Zircons separated from an meta-granite dyke sample in the Bo Xinh complex area were dated to determine the protolith age for the complex. Nine LA-ICP-MS U-Pb zircon analyses give concordant ages concentrated at 278 Ma (weighted mean). These results indicated the protolith age of the metagranite dyke (primary magma crystallization age). These meta-granite dyke penetrated the mafic rocks of Bo Xinh complex, therefore it can be confirmed that the crystallization age of the mafic rocks of Bo Xinh complex must be older than 278 Ma (early Permian).

scholarly journals U-Pb zircon and hf compositon of granitoid Chieng Khuong complex

2014 ◽  
Vol 17 (2) ◽  
pp. 67-81
Author(s):  
Nhu Thanh Ha ◽  
Hieu Trung Pham
Keyword(s):  
Partial Melting ◽  
Isotopic Ratio ◽  
Hf Isotope ◽  
Primary Magma ◽  
Late Paleozoic ◽  
Mantle Material ◽  
Weighted Mean ◽  
Forming Process ◽  
Icp Ms ◽  
Magma Crystallization

Zircon crystals selected from granitoid Chieng Khuong Complex V0938 sample and V0821 have the LA-ICP-MS U-Pb analyses clustered at 263±8 Ma. Two sample zircon analyses give concordant ages concentrated at 263± 8 Ma (weighted mean). These results indicate the protolith of the granitoid Chieng Khuong Complex (primary magma crystallization age) to be late Paleozoic (ca. 263 Ma). The results Hf(t) of Chieng Khuong granitoid show that Hf isotopic ratio from -6.4 to-13.3, indicated granitoid was formed in a complicated environment and origin through partial melting of Proterozoic crust. Combine with Hf isotope and petrological probably indicating existence of the mixture between crust and mantle material during the formation of the magma. Thus, these rusults indicate the mixing crust – mantle model which is the main way to forming process of Chieng Khuong complex.

scholarly journals The emplacement age of the Muntele Mare Variscan granite (Apuseni Mountains, Romania)

2009 ◽  
Vol 60 (6) ◽  
pp. 495-504 ◽  
Author(s):  
Ioan Balintoni ◽  
Constantin Balica ◽  
Monica Cliveţi ◽  
Li-Qiu Li ◽  
Horst Hann ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Variscan Orogeny ◽  
Weighted Mean ◽  
Apuseni Mountains ◽  
Inductively Coupled ◽  
Icp Ms ◽  
Plasma Mass Spectrometry ◽  
History Of ◽  
The Alps ◽  
Last Stage

The emplacement age of the Muntele Mare Variscan granite (Apuseni Mountains, Romania)Like the Alps and Western Carpathians, the Apuseni Mountains represent a fragment of the Variscan orogen involved in the Alpine crustal shortenings. Thus the more extensive Alpine tectonic unit in the Apuseni Mountains, the Bihor Autochthonous Unit is overlain by several nappe systems. During the Variscan orogeny, the Bihor Unit was a part of the Someş terrane involved as the upper plate in subduction, continental collision and finally in the orogen collapse and exhumation. The Variscan thermotectonic events were marked in the future Bihor Unit by the large Muntele Mare granitoid intrusion, an S-type anatectic body. Zircon U-Pb laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) dating yielded a weighted mean age of 290.9 ± 3.0 Ma and a concordia age of 291.1 ± 1.1 Ma. U-Pb isotope dilution zircon analyses yielded a lower intercept crystallization age of 296.6 + 5.7/-6.2 Ma. These two ages coincide in the error limits. Thus, the Muntele Mare granitoid pluton is a sign of the last stage in the Variscan history of the Apuseni Mountains. Many zircon grains show inheritance and/or Pb loss, typical for anatectic granitoid, overprinted by later thermotectonic events.

Petrogenesis of Silicic Rocks from the Phan Si Pan - Tu Le region of the Emeishan Large Igneous Province, Northwestern Vietnam

2021 ◽  
pp. SP518-2020-253
Author(s):  
Thuy Thanh Pham ◽  
J. Gregory Shellnutt ◽  
Tuan-Anh Tran ◽  
Steven W. Denyszyn ◽  
Yoshiyuki Iizuka
Keyword(s):  
Basaltic Magma ◽  
Red River ◽  
Granitic Rocks ◽  
Large Igneous Province ◽  
Weighted Mean ◽  
Emeishan Large Igneous Province ◽  
Icp Ms ◽  
Igneous Province ◽  
Single Grain ◽  
Host Rocks

AbstractThe Permian silicic rocks in the Phan Si Pan (PSP) uplift area and Tu Le (TL) basin of NW Vietnam (collectively the PSP-TL region) are associated with the Emeishan Large Igneous Province (ELIP). The Permian Muong Hum, Phu Sa Phin, and Nam Xe - Tam Duong granites, and Tu Le rhyolites are alkali ferroan A1-type granitic rocks, which likely formed by fractional crystallization of high-Ti basaltic magma that was contaminated by melts derived from the Neoproterozoic host rocks. Zircon U-Pb LA-ICP-MS geochronology yielded weighted-mean 206Pb/238U ages of 246 ± 3 Ma to 259 ± 3 Ma for granites, and 249 ± 3 Ma and 254 ± 2 Ma for rhyolites. This is contrasted with previously-published high precision U-Pb ages, obtained using CA-ID-TIMS method applied on the same zircon grains, which suggest that the calculated LA-ICP-MS U-Pb ages are variably inaccurate by up to 10 Ma, though at the single-grain level dates generally agree within uncertainty. The similarity of rock texture, whole-rock geochemistry, emplacement ages, and fractionation phases between the PSP-TL region and silicic rocks in the Inner Zone ELIP (i.e., Panzhihua, Binchuan) suggests they were spatially proximal before being sinistrally displaced along the Ailao Shan-Red River shear zone.

Caledonian terrane amalgamation of Svalbard: detrital zircon provenance of Mesoproterozoic to Carboniferous strata from Oscar II Land, western Spitsbergen

2013 ◽  
Vol 150 (6) ◽  
pp. 1103-1126 ◽  
Author(s):  
DETA GASSER ◽  
ARILD ANDRESEN
Keyword(s):  
Detrital Zircon ◽  
Large Scale ◽  
Strike Slip ◽  
Western Coast ◽  
Zircon Age ◽  
The North ◽  
Tectonic History ◽  
Icp Ms ◽  
Depositional Age ◽  
Sveconorwegian Orogen

AbstractThe tectonic origin of pre-Devonian rocks of Svalbard has long been a matter of debate. In particular, the origin and assemblage of pre-Devonian rocks of western Spitsbergen, including a blueschist-eclogite complex in Oscar II Land, are enigmatic. We present detrital zircon U–Pb LA-ICP-MS data from six Mesoproterozoic to Carboniferous samples and one U–Pb TIMS zircon age from an orthogneiss from Oscar II Land in order to discuss tectonic models for this region. Variable proportions of Palaeo- to Neoproterozoic detritus dominate the metasedimentary samples. The orthogneiss has an intrusion age of 927 ± 3 Ma. Comparison with detrital zircon age spectra from other units of similar depositional age within the North Atlantic region indicates that Oscar II Land experienced the following tectonic history: (1) the latest Mesoproterozoic sequence was part of a successor basin which originated close to the Grenvillian–Sveconorwegian orogen, and which was intruded byc. 980–920 Ma plutons; (2) the Neoproterozoic sediments were deposited in a large-scale basin which stretched along the Baltoscandian margin; (3) the eclogite-blueschist complex and the overlying Ordovician–Silurian sediments probably formed to the north of the Grampian/Taconian arc; (4) strike-slip movements assembled the western coast of Spitsbergen outside of, and prior to, the main Scandian collision; and (5) the remaining parts of Svalbard were assembled by strike-slip movements during the Devonian. Our study confirms previous models of complex Caledonian terrane amalgamation with contrasting tectonic histories for the different pre-Devonian terranes of Svalbard and particularly highlights the non-Laurentian origin of Oscar II Land.

High-resolution LA-ICP-MS trace-element mapping of magmatic biotite: A new approach for studying syn- to post-magmatic evolution

2020 ◽  
Vol 58 (3) ◽  
pp. 293-311 ◽  
Author(s):  
Zeinab Azadbakht ◽  
David R. Lentz
Keyword(s):  
New Brunswick ◽  
Trace Element ◽  
Inductively Coupled Plasma ◽  
Fluid Phase ◽  
New Approach ◽  
Inductively Coupled ◽  
Icp Ms ◽  
Magma Crystallization ◽  
Topaz Granite

ABSTRACT Biotite grains from 22 felsic intrusions in New Brunswick were mapped in situ using a laser ablation-inductively coupled plasma-mass spectrometer (LA-ICP-MS). We investigated the extent to which biotite can retain its magmatic zoning patterns and, where zoning does exist, how it can be used to elucidate early to late stage, syn-magmatic to post-crystallization processes. Although the major element and halogen contents of the examined biotite phenocrysts are homogeneous, two-thirds of the grains display trace-element zoning for Ba, Rb, and Cs. The results also indicated that zoning is better retained in larger grains (i.e., > 500 × 500 μm) with minimal alteration and mineral inclusions. An exceptionally well-zoned Li-rich siderophyllite from the Pleasant Ridge topaz granite in southwestern New Brunswick shows Ti, Ta, Sn, W, Cs, Rb, and V (without Li or Ba) zoning. Cesium values increase from 200 to 1400 ppm from core to rim. Conversely, Sn and W values decrease toward the rim (50 to 10 and 100 to 10 ppm, respectively). Tantalum and Ti values show fewer variations but drop abruptly close to the rim of the grain (100 to 20 and 2000 to 500 ppm, respectively). These observations may indicate crystallization of mineral phases with high partition coefficients for these highly incompatible elements (except Ti) (e.g., cassiterite and rutile) followed by fractionation of a fluid phase at a later stage of magma crystallization. The preservation of zoning may indicate rapid cooling post-crystallization of the parent magma.

scholarly journals U-Pb zircon age of the youngest magmatic activity in the High Tatra granites (Central Western Carpathians)

2013 ◽  
Vol 40 (2) ◽  
pp. 134-144 ◽  
Author(s):  
Jolanta Burda ◽  
Aleksandra Gawęda ◽  
Urs Klötzli
Keyword(s):  
Inductively Coupled Plasma ◽  
Age Groups ◽  
Hydrothermal Activity ◽  
Magmatic Activity ◽  
Zircon Age ◽  
Inductively Coupled ◽  
Icp Ms ◽  
Plasma Mass Spectrometry ◽  
Central Western Carpathians ◽  
High Tatra Mountains

Abstract Detailed cathodoluminescence (CL) imaging of zircon crystals, coupled with Laser Ablation Multi-Collector Inductively Coupled Plasma Mass Spectrometry (LA-MC-ICP-MS) U-Pb zircon dating was used to develop new insights into the evolution of granitoids from the High Tatra Mountains. The zircon U-Pb results show two distinct age groups (350±5 Ma and 337±6 Ma) recorded from cores and rims domains, respectively. Obtained results point that the last magmatic activity in the Tatra granitoid intrusion occurred at ca. 330 Ma. The previously suggested age of 314 Ma reflects rather the hydrothermal activity and Pb-loss, coupled with post-magmatic shearing.

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