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U-Pb Geochronology of the Jebba Granitic Gneiss and Its Implications for the Paleoproterozoic Evolution of Jebba Area, Southwestern Nigeria
Jebba Area Nigeria Granitic Gneiss U-Pb Dating Paleoproterozoic Eburnean Orogeny
2013/3/11
Jebba area southwestern Nigeria forms part of the Nigerian basement complex which lies in the Neoproterozoic PanAfrican mobile belt. It is underlain by several lithological units among which is a poly...
Early Proterozoic U-Pb Zircon Ages from Basement Gneiss at the Solovetsky Archipelago, White Sea, Russia
Solovetsky Archipelago Granitic Gneiss Outcrop Age Determination 2.430 Ga
2013/3/7
The central region of the Neoarchaean Belomorian Mobile Belt (BMB) is, except for the Solovetsky Archipelago, largely covered by the White Sea. A newly discovered granitic gneiss outcrop on Solovetsky...
通过闽西地区永安盆地与崇安盆地下白垩统坂头组凝灰岩夹层中的岩浆锆石定年研究以及古生物研究,首次获得2个盆地坂头组底部开始沉积的准确年龄,分别为(144±2)和(116±2)Ma。根据它们与上覆地层关系来看,2个盆地坂头组顶部年龄基本等时约为100 Ma。因此,崇安盆地坂头组仅相当于永安盆地吉山剖面上段。在与临区地层对比时,建议将永安盆地坂头组与浙西建德群以及上覆的馆头组对比,而崇安盆地下梅剖面的坂...
来自年轻沉积物或现代河流的碎屑锆石是研究大陆地壳生长演化的理想载体.为揭示华北克拉通东部和苏鲁造山带大陆地壳的生长演化,采集了中国东部大清河、潮白河、辽河、大沽河和胶莱河的5个地方的河沙样品,并对分选出来的碎屑锆石进行了LA-ICP-MS和MC-LA-ICP-MS U-Pb定年和Hf同位素微区原位分析,获得了396个锆石U-Pb谐和年龄及其对应的Hf同位素组成.2.4~2.5 Ga和1.8~1.9...
介绍了太行山南段西安里岩体角闪辉长岩的锆石U-Pb年代学、锆石Hf同位素以及岩石地球化学资料,以便对该类岩石的成因给予制约.西安里岩体主要由一套含橄榄石角闪辉长岩-角闪闪长岩-闪长岩构成.角闪辉长岩中的锆石自形程度较高,内部结构均匀,呈条痕状吸收,Th/U值介于1.44~2.85之间,表现出岩浆成因特征,其206Pb/238U年龄介于135~127 Ma之间,15个点的加权平均年龄为131±1 M...
New Constraints from Pb-Evaporation Zircon Ages of the Méiganga Amphibole-Biotite Gneiss, Central Cameroon, on Proterozoic Crustal Evolution
Metasediment 207Pb/206Pb Ages Crustal Evolution
2013/3/6
The amphibole biotite gneiss (ABGn) in the Méiganga area forms part of a meta volcano-sedimentary sequence of the Adamawa Yade domain (AYD), Central African Fold Belt (CAFB). This sequence shows affin...
Sveconorwegian U-Pb zircon and monazite ages of granulite-facies rocks,Hisarøya,Gulen,Western Gneiss Region,Norway
Sveconorwegian U-Pb zircon monazite ages granulite-facies rocks
2009/12/3
U-Pb zircon data from newly discovered granulite-facies rocks on Hisarøya, Gulen,Western Norway, yield a discordia line with upper and lower intercepts of 1646 ± 110 Ma and 987 ± 10 Ma, respect...
Silurian gabbro-diorite-trondhjemite plutons in the Trondheim Nappe Complex,Caledonides,Norway:petrology and U-Pb geochronology
Silurian gabbro-diorite-trondhjemite plutons Trondheim Nappe Complex petrology U-Pb geochronology
2009/12/2
Large bodies of trondhjemite, up to 200 km2 in size and locally coexisting with diorite and gabbro, represent an important plutonic component of the Köli Nappes in the Trondheim Region. Zircon (a...
Geochronology of high-grade metamorphism in the Sveconorwegian belt,S. Norway:U-Pb,Th-Pb and Re-Os data
Geochronology high-grade metamorphism Sveconorwegian belt U-Pb Th-Pb Re-Os
2009/12/2
The timing of Sveconorwegian high-grade metamorphism is evaluated in the four lithotectonic units / terranes exposed in the Sveconorwegian belt in South Norway. U-Pb, Th-Pb and Re-Os data were obtaine...
U-Pb zircon SHRIMP ages,geochemical and Sr-Nd isotopic compositions of the Early Cretaceous I-type Sarıosman pluton,Eastern Pontides,NE Turkey
SHRIMP dating Sarı osman pluton mineral chemistry I-type Sr-Nd isotope geochemistry eastern Pontides
2010/1/11
The petrogenesis and U-Pb SHRIMP zircon ages of the Late Cretaceous Sarıosman pluton in the Eastern Pontides is investigated by means of whole-rock Sr-Nd isotope data with field, petrographic and...