نتایج جستجو برای: basalt
تعداد نتایج: 3610 فیلتر نتایج به سال:
The Ontong Java and Manihiki oceanic plateaus are believed to have formed through high-degree melting of a mantle plume head. Boninite-like, low-Ti basement rocks at Manihiki, however, imply a more complex magma genesis compared with Ontong Java basement lavas that can be generated by ∼30% melting of a primitive mantle source. Here we show that the trace element and isotope compositions of low-...
The Paleocene-Eocene thermal maximum (PETM) has been attributed to a sudden release of carbon dioxide and/or methane. 40Ar/39Ar age determinations show that the Danish Ash-17 deposit, which overlies the PETM by about 450,000 years in the Atlantic, and the Skraenterne Formation Tuff, representing the end of 1 +/- 0.5 million years of massive volcanism in East Greenland, are coeval. The relative ...
It is important to develop Martian soil simulants that can be used in Mars exploration programs and Mars research. A new Martian soil simulant, called Jining Martian Soil Simulant (JMSS-1), was developed at the Lunar and Planetary Science Research Center at the Institute of Geochemistry, Chinese Academy of Sciences. The raw materials of JMSS-1 are Jining basalt and Fe oxides (magnetite and hema...
Cross-ply laminates reinforced with basalt fibers and functionalized multi-walled carbon nanotubes (MWCNTs) were fabricated from unidirectional epoxy prepregs. MWCNTs with varied surface conditions were prepared by oxidization or esterification, and then dispersed into a DGEBA epoxy system. The dispersion of the MWCNTs in the epoxy was improved by surface modification, resulting in improved com...
Natural fibre reinforced polylactic acid (PLA) foams, as potential green replacements for petroleum-based polymer foams, were investigated. Highly porous (ε > 95%) microcellular PLA foams were manufactured by supercritical CO2 assisted extrusion process. To overcome the inherent low melt strength of PLA, epoxyfunctionalized chain extender was applied, while talc was added to improve its crystal...
This paper focuses on acoustic reflectivity of the ocean bottom, and describes inversion of reflection data from an experiment designed to study the physical properties and structure of the ocean bottom. The formalism of Bayesian inference is reviewed briefly to establish an understanding of the approach for inversion that is in widespread use. A Bayesian inversion of ocean bottom reflection co...
Microbial corrosion textures in volcanic glass from Cenozoic seafloor basalts and the corresponding titanite replacement microtextures in metamorphosed Paleoarchean pillow lavas have been interpreted as evidence for a deep biosphere dating back in time through the earliest periods of preserved life on earth. This interpretation has been recently challenged for Paleoarchean titanite replacement ...
Microscopical studies were carried out, in addition to physico-chemical and mineralogical analysis, in order to evaluate the effect of parent material and weathering on soil genesis in forest regions of Lahijan. Two representative soil pedons in mountain landform developed on granite and andesitic basalt located about 8 km southeast of Lahijan were selected and sampling were taken from each hor...
کانی شناسی بخش رس و ژئوشیمی خاکهای تشکیل شده از سنگ های مادری دگرگون و آذرین قلیایی در ناحیه لاهیجان
The mineralogical and geochemical composition of the soils of three representat ive pedons fanned on basaltic andesite, andes itic basalt and phyllite were investigated. Results by XRF showed that progressive weathering of rocks have been marked by gradual accumulation of AI, Fe, Ti, Mg. H30+ and depletion of Na, K, Ca and Si in the soi l; although, predominant clay, loss and gain trend of...
In this research, the effect of different matrix materials (epoxy and vinylester) on mechanical properties Basalt, Jute, Glass fiber-based hybrid composites were analyzed mechanically morphologically. The test results achieved by Tensile Vickers hardness test, while morphologic images obtained Scanning Electron Microscopy. Basalt fiber fabric, Jute fabrics 86 gr/m² 100 used as reinforcement ele...
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