The Deh-Sard area IS located about 90 km south of
8aft in the Kerman province, situated in southern part of
Sanandaj-Sirjan zone. It consists of interm ittent lava flows
(basalt, basaltic andes ite and trachyandesite), pyroclastic rocks
(various types of tu ffs and paloebereccias) and sedimentary
rocks (lime stones and shales) of Jurassic age. The Deh-Sard
lava flows are essentially composed of plagioclase (both as
phenocryst and microlite), clinopyroxene (diopside-augite) and
accessory minerals (opaque and apatite). Secondary minerals
such as quartz, chlorite and calcite occur both as a materix and
as a pore fill ing minerals. The main textures of the Java flows
are microlitic porphyritic, intergranular and intersertal. The
plagioclase crystals have disequilibrium characteristics such as
sieve texture, resorption phenomena, reaction with magma,
corrosion and oscillatory zon ing. These are associated with,
mineral grindings and formation of Fe-Ti oxides In the
cleavage planes of the clinopyroxenes. All of these evidences
confirm the formation of disequilibrium conditions as a result
of decompression, caused b~ fast magma uprising toward the
earth surface. In the evolution of these crystals, minor
processes such as rapid ske letal growth as a result of quench
crystall ization, effects of PHZO and magma mixing are also
played ao important rule.
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