DIAGENETIC HISTORY OF THE ROCK UNITS OF BOZKIR UNIT CONTROLLED BY THE TRIASSIC RIFTING, BOZKIR-KONYA

Year 2016, Volume: 153 Issue: 153, 63 - 90, 26.10.2016

Hüseyin Yalçın Ömer Bozkaya Mine Takçı

https://doi.org/10.19111/bulletinofmre.266051

Cited By: 2

Abstract

The Bozkır Unit representing the
northern edge of the Taurus Belt comprises, from bottom to top, three distinct
structural entities; the Upper Triassic pre-rift (Korualan Group), the Upper
Triassic-Upper Cretaceous syn-rift (Huğlu Group) and the Jurassic-Cretaceous
Boyalı Tepe Group as to their structural settings. The Korualan Group is
represented by the alternations of carbonate (limestone, dolomitic limestone,
dolomite) with radiolarite and chert intercalations and clastic rocks
(sandstone, siltstone, mudstone, shale). The Huğlu Group is made up of volcanic
(basalt, andesite) and pyroclastic (tuffaceous sandstone) rocks including
radiolarite, limestone and clastic rock (sandstone, siltstone, shale)
intercalations. The Boyalı Tepe Group is completely made of carbonate rocks.
The carbonate-silisiclastic-volcanogenic rocks of the Bozkır Unit contain
carbonate (calcite, dolomite), quartz, feldspar (plagioclase, anorthoclase),
phyllosilicate (illite, chlorite, mixed-layered illite-chlorite / I-C,
chlorite-vermiculite / C-V, chlorite-smectite / C-S, rare smectite), augite,
hematite, analcime and heulandite in order of abundance. On the basis of illite
Kübler Index data; Korualan and Huğlu Group reflect low grade diagenetic, high
grade diagenetic and high grade diagenetic-anchizonal characteristics,
respectively. The illite/micas of the pre-rift units and units related to the
rifting have muscovitic, and phengitic and seladonitic compositions,
respectively. The distributions of chondritenormalized trace and rare earth element
(REE) contents in illites present similar trends for Korualan ve Huğlu groups,
but the quantities of these elements slightly increase in the Huğlu Group.
δ18O–δD isotopic compositions of water forming the illite minerals are
different than that of sea water and are found to be between the Eastern
Mediterranean Meteoric Water (EMMW) and magmatic water compositions. It also
shows that temperature of the water forming illite minerals varies from low to
high values. The findings from the rocks of Bozkır Unit suggest that pre- and
syn-rift units have different mineralogical-petrographic and geochemical
properties. The younger units within the rift due to extension and crustal
thinning related to rifting must have been exposed in higher diagenetic conditions
by more burial and heat with respect to older units on the edges.

Keywords

Taurus Belt, Extensional basin, Phyllosilicate, Mineralogy and Geochemistry

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