Geological structure and tectonics of the Chovdar ore deposit

Abstract

The Çovdar ore field, located in the southwestern part of Azerbaijan, is of significant geological importance, both for its mineral deposits and its complex tectonic setting. Situated within the broader context of the Alpine-Himalayan orogenic belt, the area is influenced by the tectonic interactions between the Eurasian and Arabian plates. These interactions have played a crucial role in shaping the field’s geological framework and contributed to its rich mineralization. The region is characterized by a variety of geological formations, including sedimentary, volcanic, and metamorphic rock units, which have undergone multiple stages of deformation due to ongoing tectonic forces.

The geological structure of the Çovdar ore field consists primarily of rocks dating from the Paleozoic to the Mesozoic eras, with significant contributions from sedimentary, volcanic, and metamorphic sequences. These lithological units include carbonates, sandstones, shales, and volcanic tuffs. Over time, the sedimentary and volcanic rocks have undergone significant deformation, manifesting as folds, faults, and thrusts, reflecting the compressional nature of regional tectonic forces. These structural features are essential for the formation of the ore deposits within the region, which are primarily composed of gold, copper, and iron, among other minerals. Tectonically, the Çovdar area has experienced a series of phases of deformation, corresponding to the dynamic processes occurring within the surrounding regions of the South Caspian Basin. The initial phase of sedimentary deposition occurred in a marine environment, during which thick carbonate sequences were laid down. This was followed by a significant phase of compressional tectonics, marked by folding and faulting, which created fractures and zones of weakness within the rock units. These tectonic events set the stage for the development of ore deposits, as mineralizing fluids were channeled along these structures.

In the late Cenozoic era, tectonic forces related to the ongoing collision between the Eurasian and Arabian plates further intensified. This period witnessed the uplift of the region, creating additional fault zones and structural features, which allowed for the circulation of hydrothermal fluids. These mineral-rich fluids, originating from deep within the Earth’s crust, interacted with the host rocks, resulting in the metasomatic alteration of minerals and the formation of ore bodies, particularly in faulted and fractured zones. The Çovdar ore field is notable for its strong association with tectonic features such as fault zones, fractures, and fold structures. These geological structures have provided the necessary conduits for the migration of mineralizing fluids, allowing for the concentration of valuable minerals in specific locations. The ore deposits are often found within or adjacent to these zones of deformation, with mineral veins and breccia zones serving as primary hosts for gold and copper mineralization. The mineralization process is closely tied to the thermal and chemical conditions created by tectonic movements, which promoted hydrothermal alteration and the concentration of valuable elements.

The tectonic history of the region is intertwined with the broader geological evolution of the South Caspian Basin and the surrounding Caucasus region. The tectonic setting of the Çovdar area reflects the dynamic nature of continental collision, crustal thickening, and the formation of large-scale fault systems. These processes have played a key role in the formation of localized ore zones, where mineralizing fluids, driven by the high geothermal gradients of the region, have deposited significant amounts of metal ores. Furthermore, ongoing tectonic activity continues to influence the geological stability of the Çovdar field. The interaction between the local fault systems and the broader regional tectonic movements is essential for understanding the behavior and potential longevity of the ore deposits. The continuing uplift and deformation of the region may lead to the creation of new mineralized zones, further enhancing the resource potential of the area.