The Jarando Basin Is Situated 200 Km South of Belgrade, Covering the Area of Approximately 320 Km2
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The Jarando basin is situated 200 km south of Belgrade, covering the area of approximately 320 km2. It is a northwest-southeast elongated tectonic depression with a maximum length of 20 km and width of 12 km, and consists of several coal mines. At present coal is exploited in two underground mines: Jarando and Tadenje, and one open pit mine Progorelica. The Lower Miocene Jarando basin was formed over the paleorelief made of Paleozoic, Mesozoic and Tertiary rocks. Paleozoic is represented by chlorite schist, hartzburgite and serpentinite. Mesozoic sedimentary rocks include Triassic limestone, dolomite, marble, sandy marlstone and marlstone, and Jurassic gabbro, rodingite and other rocks of the ophiolite mélange. Tertiary igneous rocks are Oligocene dacito-andesite lava flows, and Neogene quarztlatite/rhyodacite extrusions and pyroclastic rocks. Sedimentary rocks are mainly Neogene in age and are made of conglomerate, sandstone, three to nine coal seams, coal shale, shale and marlstone. Jarando basin is characterized by bituminous coals, whereas in the other basins coalification in the same stratigraphic level does not exceed the subbituminous stage. The basin is filled by coal-bearing clastic rocks deposited over serpentinite and volcanic rocks. Sedimentation was followed by basin subsidence resulting in formation of a 1500 m thick sequence (based on geophysical exploration). Sedimentation took place in a lacustrine system that was associated to contemporaneous volcanic activity. This volcanic activity was an additional factor that gave rise to higher temperature in the shallow crustal levels. It was accomapnied by intrusive magmatism represented by I-type Oligocene granitoid of Mt. Kopaonik and S- type Miocene granite of Polumir. In addition, the basin hosts boron mineralization (borates and howlite) and magnesite deposit and that further implies elevated temperatures in this lacustrine system and can indicate a possible role of hydrothermal solutions. Previous studies of the Jarando basin were related mostly to stratigraphic classification, and exploration of mineral resources (coal, boron minerals, magnesite, dolomite). However, none of the earlier studies focused on elucidating more detailed characteristics of the basin evolution, especially in terms of its heat flow regime. .