Kosovo has a varied geology that ranges in age from the Neo-Proterozoic to the Holocene. The geology is characterised by substantial structural features on a regional scale, including normal faulting and thrusting. A general simplification of the stratigraphic sequence is as follows.
Holocene: scree formed from weathering of mountains and alluvium deposited by the rivers.
Pliocene: andesitic chert.
Upper Miocene-Pliocene: formation of lignite from the accumulation and subsequent decay of vegetation in sedimentary basins.
Oligo-Miocene: conglomerates, clays and limestones, accompanied by acidic to intermediate magmatism.
Late Cretaceous 'molasse': shallow-water carbonates and clastics.
Upper Cretaceous 'flysch': marly limestones, sandstones and conglomerates.
Early Cretaceous: conglomerates, sandstones and silts.
Late Jurassic: massive limestones.
Triassic-Jurassic: basic and acidic magmatism, and associated ophiolitic crustal rifting and obduction of ultrabasic rocks.
Triassic: clastics with volcanics giving way to carbonate platforms that grade up into dolomites, some of which have been metamorphosed to marble.
Permo-Triassic: carbonates, clastics, phyllite, schists and quartzites that have been invaded by acidic magmatism (quartz porphyries).
Late Palaeozoic: schists.
Neo-Proterozoic-Palaeozoic: basement of schists, gneisses and amphibolites that have been invaded by granitic plutons.
Geology of Kosovo
The oldest rocks form the Neo-Proterozoic basement, which is composed of crystalline schists and granites, representing the products of regional high-grade metamorphism. These rocks mainly outcrop in the northeast of Kosovo. Laid down on top of this continental basement was an extensive sequence of shallowwater marine sediments (clastic and chemical) of Late Permian to Early Triassic age that were invaded by acid magmas as the continental crust thinned, resulting in the anatexis of preexisting rocks. Continued stretching and thinning led to physical separation of the continental crust, resulting in the extrusion of basalt, hosting highly irregularly shaped pods of high-grade chromite. This separation was extensive enough to lead to the formation of the Paratethys Ocean that ran across the Balkans, including Kosovo. The Paratethys was a branch of the main Tethys Ocean that ran across southern Europe, the Mediterranean and North Africa. A reversal of tectonic plate movement led to the eventual closure of the Mesozoic-age Tethys Ocean, including a segment called the Vardar Ocean (Paratethys) across Kosovo. By late Jurassic times, the presence of a remnant Vardar Ocean as a shallow sea led to the chemical deposition of thick and extensive carbonate platforms. By Cretaceous times, the eventual retreat of this sea and the stability provided as a passive continental margin, led to the deposition of clastic sediments that range from marine to terrestrial in origin. Collision between the landmasses that had flanked the Vardar Ocean forced the westward obduction of remnants of oceanic crust upon continental crust. The result is the remnants of oceanic crust found throughout the Balkans, forming linear ophiolitic sequences aligned along the regional NNW-SSE regional structural trend. These obduction events are polyphase and would appear to represent crustal accretion, resulting in the development of several linear belts of ophiolites, ranging in age of obduction from Jurassic to Cretaceous. The rocks that were overthrust during the emplacement of ophiolites are called the 'sole'; rocks and form units called mélange. Such ophiolitic mélanges are characteristically composed of chert, serpentinite, mafic volcanics and carbonates, all of which may be in the form of fragments within chaotically sorted olistostrome units. In Late Cretaceous times, extensive continental collision during the Alpine Orogeny led to the formation of the Alps and associated mountain ranges throughout central and southern Europe. The rapid erosion of these contorted rocks of both marine and continental origin resulted in the deposition of the flysch cover sequence, composed of marly limestones and clastics. As the Alpine Orogeny waned, so the young mountain ranges were eroded to produce the continental molasse cover sequence that formed predominantly in intermontane basins throughout the Alpine Zone. Some of the continental clastic sediments preserved in Kosovo probably represent molasse deposits. Basin depressions within Kosovo were sites of luxuriant vegetation growth that finally became overwhelmed by sedimentation and led to the formation of the substantial stratiform lignite deposits that are mined by KEK. The Pleistocene glaciations that affected Europe removed much of the soil cover from Kosovo’s ring of surrounding mountains, leading to the formation of substantial talus deposits along the steep mountain flanks.