The Archaean High-Mg Diorite Suite: Links to Tonalite-Trondhjemite-Granodiorite Magmatism and Implications for Early Archaean Crustal Growth
نویسندگان
چکیده
منابع مشابه
Early basic magmatism in the evolution of Archaean high-grade gneiss terrains: an example from the Lewisian of NW Scotland
Amphibolite blocks from an Archaean (2.9 Ga) trondhjemite-agmatite complex in the Lewisian at Gruinard Bay have a varied trace element and R E E content. Whilst some of the variability is attributable to element mobility during high-grade metamorphism and subsequent trondhjemite magmatism, it is for the main part considered to be a primary feature of the amphibolites. The observed trace element...
متن کاملPetrogenesis of the Bir Madi gabbro-diorite and tonalite-granodiorite intrusions, South Eastern Desert, Egypt: Implications fo
The Neoproterozoic rocks of the Bir Madi area, south Eastern Desert, comprise a metagabbrodiorite complex (GDC) and a tonalite-granodiorite suite (TGrS). The GDC has a weak tholeiitic to strong calc-alkaline character and is made up of olivine gabbro, hornblende gabbro, diorite and monzodiorite. The olivine gabbro is characterized by abundance of augite and labradorite with pseudomorphic serpen...
متن کاملThe tonalite–trondhjemite–granodiorite (TTG) to granodiorite–granite (GG) transition in the late Archean plutonic rocks of the central Wyoming Province1
The 2.95–2.82 Ga quartzofeldspathic gneisses and granitoids in the Bighorn, western Owl Creek, and northeastern Wind River uplifts in the central Wyoming Province include low-K tonalite–trondhjemite–granodiorite (TTG) and high-K granodiorite–granite (GG) rocks. Both types of granitoids were intruded contemporaneously, although TTGs are more abundant in the older gneisses. The TTG suite consists...
متن کاملFossil evidence of Archaean life.
Evidence for the existence of life during the Archaean segment of Earth history (more than 2500 Myr ago) is summarized. Data are presented for 48 Archaean deposits reported to contain biogenic stromatolites, for 14 such units reported to contain 40 morphotypes of putative microfossils, and for 13 especially ancient, 3200-3500 Myr old geologic units for which available organic geochemical data a...
متن کاملComment on "Early Archaean microorganisms preferred elemental sulfur, not sulfate".
Philippot et al. (Reports, 14 September 2007, p. 1534) interpreted multiple-sulfur isotopic compositions of approximately 3.5-billion-year-old marine sulfide deposits as evidence that early Archaean microorganisms were not sulfate reducers but instead metabolized elemental sulfur. However, their data can be better explained by a scenario involving poor mixing of photochemical and surface sulfid...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of Petrology
سال: 2000
ISSN: 1460-2415
DOI: 10.1093/petrology/41.12.1653