Scientific Quarterly Journal of Geosciences

Scientific Quarterly Journal of Geosciences

Textural and Structural Investigation on the Chromite deposition Gaft and Foromad Areas, Sabzehvar

Document Type : Original Research Paper

Authors
Hamidreza Vatanpour 1
Alijan Aftabi 2
1 Ministry of Education, District One, Mashhad, Iran
2 Department of Geology, Faculty of Sciences, University of Shahid Bahonar, Kerman, Iran
Abstract
This paper deals with on the most important kind of structures and textures of the chromite deposits in Goft and Foromad areas of Sebzehvar for the first time. The area under investigation is situated in the most westerly part of Sebehvar Ophiolitic Belt and north-west of the town of Sabzehvar. It consists of several pencil-shaped, lenticular and layered chromite deposits, with varying dimensions, in serpentinized ultrabasic rocks, most of which are serpentinized harzburgite.
With regards to the results obtained from this investigation, the structure and texture present in the area may be divided into two principal groups:
1.  Initial textures and structures.
2. Secondary textures and structures.
Among the most important initial structures and textures, one may hint at, their scattered, reacting, accumulating, inter - accumulating, reticulate, vermicular, nodular, skeletal, massive, dense, banded and cross-bedded properties. Whereas, the secondary textures and structures constitutes various types of strains, cataclastics, mylonitization, brecciation, folding and faulting and ultimately supergene and island-like.
The initial textures and structures, all are resulted from crystallization, accumulation and precipitation of chromite accompanied with silicates of olivine and pyroxene, at various stages of crystallization and basaltic magma. While the secondary ones are formed from deformation and contortion caused by tectonic and non-tectonic phenomena.
Thus, the above-mentioned points are of utmost importance in exploration and exploitation of chromites.
Keywords
Chromite deposition, Foromad, Sabzehvar

Subjects

 
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Scientific Quarterly Journal of Geosciences
Volume 6, 23-24
Spring & Summer 1998, Vol. 6, No. 23-24
Autumn 1998
Pages 40-56