Abstract:

There are many acidic intrusions of varying age in the northern and southern zones of the eastern Pontides, NE Turkey, and the Sarıhan Granitoid is one of these. The Maastrichtian Sarıhan Granitoid was emplaced into the pre-Permo-Carboniferous Pulur Massif, generally comprising medium-grade metamorphic rocks; the Liassic Hamurkesen Formation, that begins with the Dikmetaş conglomerate and continues upward into volcano-sedimentary rocks; and the Malm-Lower Cretaceous Hozbirikyayla Formation, comprising limestone and sandy limestones. The Sarıhan Granitoid crops out in an area of approximately 40 km2, has an ellipsoidal shape, and comprises mainly quartz monzodiorite, granodiorite and lesser quartz diorite. The pluton contains volcanic and silicified limestone xenoliths and dioritic mafic microgranular enclaves. The plutonic rocks show medium-grained, poikilitic, monzonitic, anti-rapakivi and sometimes myrmekitic textures, and contain 43-64% plagioclase, 6-18% orthoclase, 10-29% quartz, 5-20% hornblende, 1-85% biotite, 1-6% opaque oxides, accessory amounts of apatite, titanite and zircon, and secondary phases of calcite, chlorite and sericite. Some textures may suggest magma mixing, whereas the presence of mafic microgranular enclaves indicates that magma-mingling processes were operative in the evolution of the pluton. The pluton has 65-67% SiO2, 1.4-3.1% MgO, 4.1-5.5% Na2O and

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