نتایج جستجو برای: mafic migmatites

تعداد نتایج: 2136  

Journal: :Science 2005
J F Mustard F Poulet A Gendrin J-P Bibring Y Langevin B Gondet N Mangold G Bellucci F Altieri

Data from the Observatoire pour la Minéralogie, l'Eau, les Glaces, et l'Activité (OMEGA) on the Mars Express spacecraft identify the distinct mafic, rock-forming minerals olivine, low-calcium pyroxene (LCP), and high-calcium pyroxene (HCP) on the surface of Mars. Olivine- and HCP-rich regions are found in deposits that span the age range of geologic units. However, LCP-rich regions are found on...

Journal: :Science 1982
C M Pieters

Olivine is identified as the major mafic mineral in a central peak of Copernicus crater. Information on the mineral assemblages of such unsampled lunar surface material is provided by near infrared reflectance spectra (0.7 to 2.5 micrometers) obtained with Earth-based telescopes. The composition of the deep-seated material comprising the Copernicus central peak is unique among measured areas. O...

قاسمی, حبیب اله, بلاغی, زری , جای, مینگو , صادقیان, محمود , محجّل, محمد ,

Delbar metamorphic complex composed of schists, amphibolites and gneisses with migmatitic views belong to Neoprotrozoiec (Precambrian) is located in southeast of Shahrood. Debar metamorphic complex crosscut by at least three series of mafic dikes, with different ages (Precambrian, Jurassic and Tertiary). Jurassic dikes intruded in Precambrian metamorphic complex and upper Triassic - lower Juras...

Ghorbani, , Hajialioghli, , Moazzen, ,

The process of migmatitization in the Ghareh Naz has resulted in the formation of various rate of partial melting and eventually the formation of a large spectrum of metatexite and diatexite migmatites. Mineral chemistry studies by EPMA method shows that amphibole composition is magnesio-hastingsite and has a metamorphic origin and feldspar composition is andesine to oligoclase. Effective react...

Journal: :journal of tethys 0

the igneous dykes are a small mafic rock unit exposed in the south gorgan of eastern alborz, north iran. these mafic dykes are intruded in the middle–upper paleozoic sedimentary and metamorphic rocks units representing a part of the north gondwana province. the studied samples were collected from various locations along the exposed bodies. thin sections of these rocks show medium to coarse grai...

2015
Bi-Ji Luo Hong-Fei Zhang Wang-Chun Xu Liang Guo He Yang

An integrated study involving whole-rock and Sr–Nd–Hf isotope geochemistry and zircon geochronology and trace element combined with detailed field investigation was carried out for the composite Meiwu batholith in the West Qinling orogenic belt of central China to probe the origins of its compositional diversity and its emplacement history. The batholith is composed of quartz diorite, granodior...

2016
Shichun Huang Munir Humayun

The role of a mafic component in the petrogenesis of Oceanic Island Basalts (OIBs) is highly debated. As the best studied OIB, Hawaiian lavas provide critical insights into OIB genesis. At a given MgO content, the CaO content in the melt has been used to distinguish between partial melts of peridotite and garnet pyroxenite/eclogite. However, calculations using the BATCH program show that CaO co...

2009
Fang-Zhen Teng Roberta L. Rudnick William F. McDonough Fu-Yuan Wu

a r t i c l e i n f o Keywords: Lithium isotopes A-type granite Mafic enclave Continental crust Lithium concentrations and isotopic compositions of 39 A-type granites and mafic enclaves from 11 plutons in Northeast China and the North China craton are used to constrain their genesis and to characterize further the average composition of the continental crust. Lithium concentrations (2.8 to 80 p...

2015
Lei Zhao Colin R. Ward Ian T. Graham Antonio Simonetti

Silicic, mafic and alkali intra-seam tonsteins have been known from SW China for a number of years. This paper reports on the geochemical compositions of coals and tonsteins from three seam sections of the Songzao Coalfield, SW China, and evaluates the geological factors responsible for the chemical characteristics of the coal seams, with emphasis on the influence from different types of volcan...

Journal: :Journal of Geophysical Research: Solid Earth 2003

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید