The region that comprises the Tara Mt., the Zlatibor Mt., and the valleys of Kremna and Mokra Gora is built of magmatic, metamorphic, and sediment rocks that were formed since the Palaeozoic, through the Mesozoic, to the Cenozoic.
The oldest rocks were formed during the Lower and the Middle Palaeozoic, some 600 to 300 million years ago. They are built of sandstone, aleurolite, clay, and limestone, sedimented simultaneously with the lava flows of basic composition. During the Upper Palaeozoic, these rocks were metamorphosed, under the influence of high temperature and pressure, into metasandstone, phyllite, crystal limestone, and chlorite shale. From the end of the Devon, up to the beginning of the Triassic, 250 million years ago, these metamorphic rocks reached the surface by tectonic movements.
In the Mesozoic, at the beginning of the Lower Triassic, new tectonic movements brought back the sea into this region. From 250 to 210 million years ago, conglomerates were deposited at the sea bottom, followed by fossil rich carbonates.
During the Jurassic, which lasted from 210 to 140 million years ago, firstly formed sediments were clay, corneite, sandstone, and limestone. Following the deepening and widening of the ocean, peridotites were brought up to the rift from the upper mantle, and massive quantities of basaltic lava were spilled. Further narrowing of the ocean has pushed the peridotites over the Upper Triassic limestone and the Lower Jurassic sediments, which were metamorphosed under the influence of high temperature and pressure.
During the Upper Cretaceous, from 95 to 65 million years ago, sedimentation of limestone continued, and today they lie over the Palaeozoic rocks, Triassic limestone, and peridotites.
And finally, during the Cenozoic, namely during the Tertiary and the beginning of the Quaternary, from 65 to 1.7 million years ago, isolated basins, in which freshwater lake sediments, sands and clays were deposited, were formed after the withdrawal of the sea in depressions shaped by tectonic movements,
All dynamic processes that lead to the formation of the complex soil in this region influenced the distinct plasticity of the relief and the diversity of the vegetation cover.