Tola A. Mirza, Taher H. Ameen, Salim H. Sulaiman Al-Hakari
Department of Geology, School of Science, Faculty of Science and Science Education, University of Sulaimani/ Kurdistan Region/
Iraq.
Abstract
Small lensoidal bodies of massive and disseminated chromitites have been examined in
association with ultramafic rocks of the Mawat Ophiolite Complex (MOC), Iraqi Zagros
Thrust Zone, Northeastern Iraq. The Chromites ore have variable thickness enveloped by
dunite and of, exhibiting transitional boundaries to harzburgitic host rocks.
The primary Chromite composition exhibits high Cr varieties; the average Cr# of
Chromite is 0.714, with < 0.3 % TiO2 content, which may reflect the crystallization of
Chromite from boninitic magma. The result of the gravity survey leads to lateral
delineation of the ore body and estimates an area of about 2800 m2
.
The thicknesses of
different Chromite pods were estimated to be in the range of 10 – 35 m.
Structural feature
show that such ore bodies have internal structure making angle of 10–12
degrees with
dunite wall and surrounding peridotite which indicates that Chromite ore
subconcordant
type.
Key Words:
Chromitite,
Geophysical,
Gravimeter,
Bouguer gravity
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