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Geochemical
characteristics of the Late Miocene to Pliocene Ulumuhsine sill of the
Erenlerdagi volcanics, Konya, Central Turkey
Kocak, K.
Geology
Department, Selcuk University, Konya-TURKEY
kkocak@yahoo.com
The Late Miocene to Pliocene volcanism produced extensive formation of
lava domes, nue´e ardentes and ignimbrite deposits in west, northwest of
the Konya area Central Anatolia, Turkey. However, the Ulumuhsine sill
is unique in the volcanic system, with its rare occurrences. Regions of
the sill in which flow was short-lived have chilled margins, and
experienced a single injection of magma. It contains quartz and
calcite-filled vesicles. Main constituents are euhedral to subhedral
clinopyroxene, olivine, plagioclase and minor sanidine in a
holocrystalline porphyric texture. It is mostly metaluminous and
basaltic trachyandesite in composition, with alkaline to subalkaline
affinity. They are characterized by an enrichment of large ion
lithophile elements e.g., Cs, Rb; light rare earth elements [(La/Sm)N:3.6-4.1],
and depletion of heavy rare earth elements [(Gd/Lu)N:
1.6-1.9]. The primordial mantle normalized multi-element spidergrams of
the samples are characterized by existence of negative Nb, P and Ti
anomalies, indicating subduction signatures for their genesis. However,
various geotectonic setting diagrams imply calcalkaline basalt to within
plate alkaline basalt setting for the samples.
Key words:
sill, alkaline magma, volcanism, Konya, Turkey |