1
artículo
Publicado 2009
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We report the results of the study of a meteorite that impacted an inhabited zone in the neighborhood of the town of Carancas, Puno Region, about 1,300 km south of Lima. The analysis carried out by X ray diffractometry, transmission Mössbauer spectroscopy (at room temperature and at 4,2 K), and by energy dispersive X ray fluorescence reveal the presence in the meteorite simple of magnetic sites assigned to the Fe-Ni and troilite (Fe,S) phases, and of 3 paramagnetic doublets, two of them assigned to Fe2+, one associated to olivine and the other to pyroxene, and the third one due to a site occupied by Fe3+, which can be associated to oxides in a superparamagnetic state and/or by an Fe hydroxide. The soil samples from the crater reveal a composition that consists mainly of quartz, albite and impactites such as coesite and stishovite (SiO2). The occurrence of these phases with a high conten...
2
artículo
Herein, it is introduced the analysis of a meteoritic specimen discovered in the Peruvian Amazonia. According to the analysis by dierent physical techniques carried onto a fragment of it, this meteorite belongs to the ordinary chondrites. Specifically, we have used transmission Mössbauer spectroscopy and energy dispersive X-ray fluorescence.The results with these techniques show that the samples have relatively large amounts of Si, Al and Fe. Likewise, since transmission Mössbauer spectroscopy is an isotopically more selective technique, we have observed the presence of magnetic sites assigned to the taenite (Fe,Ni) and troilite (Fe,S) phases. We also realized the presence of three paramagnetic doublets assigned to Fe2+: one associated with olivine (Fe,Mg)2SiO4;other, to pyroxene (Fe,Mg)SiO3; and third doublet, to one Fe3+ site.
3
artículo
Publicado 2011
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This paper reports the preliminary results of the mineralogical characterization of soils from the Chancay River Valley, Lambayeque, by X ray diffractometry (XRD) and transmission Mössbauer spectroscopy (TMS). The studied soil sample, SI53, belongs to one of the two horizons of a selected soil profile from the area of Sialupe, located in the Chancay River Valley. The XRD allowed the identification of crystalline mineralogical phases in the such as found sample, at a depth of 30 cm, such as quartz, montmorillonite, clinochlore, amphibole and albite; these same minerals, except amphibole, appear also in its corresponding clay fraction. The TMS allowed the identification , in the such as found sample, of a sextet assigned to hematite and a central doublet that can be assigned to an iron oxide in the super paramagnetic state or to kaolinite; the other doublets are assigned to montmorillonit...