The Upper Cretaceous intrusive rocks with extensive crustal contribution in Hacimahmutusagi Area (Aksaray/Turkey)

The Hacimahmutusagi area (Aksaray/Turkey) is located in the western part of the Central Anatolian Crystalline Complex (CACC). Gneiss and marble compose the basement units, while intrusive rocks are gabbros and granitoids. The pegmatitic hornblende gabbros contain pegmatitic to fine-grained hornblendes, plagioclase, clinopyroxene, and accessory opaque minerals. The fine-grained gabbros, on the other hand, are composed of plagioclase, hornblende, and biotite as major components whereas the apatite and opaque minerals are present in accessory content. Granitic granodioritic rocks are the common intrusive rock types in the area, and constitute quartz, orthoclase, plagioclase and biotite, and accessory zircon and opaque minerals. Leucogranites, comprising quartz, orthoclase, plagioclase with minor biotite, hornblende, and with accessory apatite and opaque minerals, are found as dykes intruding the marble and the granitic-granodioritic rocks. Strontium neodymium isotope data of gabbros and granitoids have high Sr-87/Sr-86((i)) ratios (0.7076 to 0.7117) and low epsilon Nd-(i) values (-5.0 to -9.8) point out enriched source and pronounced crustal contribution in their genesis. In the Hacimahmutusagi area, it is plausible that the heat increase caused by the hot zone, which was generated by underplating mafic magma along with the hydrous mafic sills in the lower crust, might have resulted in partial melts from crystallized mafic sills and older crustal rocks. It can be suggested that these hybrid melts adiabatically rose to the shallow crust, ponded and crystallized there and formed the magma source of the intrusive rocks within the Hacimahmutusagi area and the other hybrid granitic rocks with crustal signatures in the CACC. Geochemical data indicate that granitoids and gabbros are collision to post-collision related sub-alkaline rocks derived from an enriched source with extensive crustal inputs.


Tectonomagmatic evolution of bimodal plutons in the central Anatolian crystalline complex, Turkey
Kadioglu, Yk; Dilek, Y; Güleç, Nilgün Türkan; Foland, Ka (University of Chicago Press, 2003-11-01)
The NW-trending Agacoren Intrusive Suite (AIS) on the east side of the Salt Lake (Tuz Golu), Turkey, is part of a curvilinear volcanoplutonic complex along the western edge of the central Anatolian crystalline complex (CACC). Granitoids constitute the predominant lithological group within the AIS and range in composition from monzonite through granite to alkali feldspar granite. Gabbroic rocks occur as irregular intrusive bodies with sinusoidal, irregular contacts with the granitoid plutons and vary from di...
Structure and recent evolution of the Hazar Basin: a strike-slip basin on the East Anatolian Fault, Eastern Turkey
Moreno, D. Garcia; Hubert-Ferrari, Aurelia; Moernaut, Jasper; Fraser, J. G.; Boes, Xavier; Van Daele, Maarten; Avşar, Ulaş; Cagatay, N.; De Batıst, Marc (Wiley, 2011-04-01)
The Hazar Basin is a 25 km-long, 7 km-wide and 216 m-deep depression located on the central section of the East Anatolian Fault zone (eastern Turkey) and predominantly overlain by Lake Hazar. This basin has been described previously as a pull-apart basin because of its rhombic shape and an apparent fault step-over between the main fault traces situated at the southwestern and northeastern ends of the lake. However, detailed structural investigation beneath Lake Hazar has not been undertaken previously to ve...
Chronology of subduction and collision along the Izmir-Ankara suture in Western Anatolia: records from the Central Sakarya Basin
Ocakoğlu, Faruk; Hakyemez, Aynur; Açıkalın, Sanem; Altıner, Sevinç; Büyükmeriç, Yeşim; Licht, Alexis; Demircan, Huriye; Şafak, Ümit; Yıldız, Ayşegül; Yılmaz, İsmail Ömer; Wagreich, Michael; Campbell, Clay (Informa UK Limited, 2019-07-03)
Western Anatolia is a complex assemblage of terranes, including the Sakarya Terrane and the Tauride-Anatolide Platform that collided during the late Cretaceous and Palaeogene (80-25 Ma) after the closure of the Izmir-Ankara Ocean. Determining the precise timing at which this ocean closed is particularly important to test kinematic reconstructions and geodynamic models of the Mediterranean region, and the chronology of suturing and its mechanisms remain controversial. Here, we document the Cretaceous-Eocene ...
DIRIK, K (Wiley; 1993-12-01)
The study area is located in the southern part of the Central Pontides. The rocks exposed in this region have been divided into three major groups: basement, cover sequence and volcanic rocks. The basement rocks are composed of metamorphic units and a chaotic assemblage derived from an accretionary prism produced during the northward subduction of northern Neo-Tethys during the Late Cretaceous. During the same period, the basal element of the cover sequence, a thick and coarsening upward flysch succession (...
Mafic microgranular enclaves and interaction between felsic and mafic magmas in the agacoren intrusive suite: Evidence from petrographic features and mineral chemistry
Kadioglu, Yusuf Kagan; Güleç, Nilgün Türkan (Informa UK Limited, 1996-01-01)
The Agacoren Intrusive Suite is exposed as a large intrusive body over ∼500 km2 east of Lake Tuz in central Anatolia and consists of the Cokumkaya gabbro, the Agacoren granitoid, and young dikes. The Agacoren granitoid is the predominant lithology of the Agacoren Intrusive Suite, and is differentiated into several subunits ranging in composition from monzonite, through granite, to alkali feldspar granite. The Cokumkaya gabbro occurs as stocks enclosed in the Agacoren granitoid; individual bodies range in si...
Citation Formats
S. Köksal, “The Upper Cretaceous intrusive rocks with extensive crustal contribution in Hacimahmutusagi Area (Aksaray/Turkey),” GEOLOGICA CARPATHICA, pp. 261–276, 2019, Accessed: 00, 2020. [Online]. Available: