Primary characteristics of selected stalagmites from four caves located between Erdemli and Silifke (Mersin), southern Turkey—implications on their formation

Abstract

This study describes the primary chacteristics of the selected stalagmites from the four caves in southern Turkey and interprets their formation via petrographic, SEM–EDX, XRD, ICP–AES and stable isotope techniques. The analytical results show that the stalagmites are composed of low Mg-calcite associated with trace to small amount of impurities such as clays. Lamination is characteristic in all the stalagmites and mainly includes sparitic and micritic growth layers. In the sparitic layers, columnar crystal fabric is common together with rare dendritic fabric. The columnar fabric consists of elongated calcite crystals and indicates slow inorganic precipitation. Whereas the dendritic fabric consists of fibrous-like calcite crystals oriented at two directions, and is related to the colonization of fungus and later their calcification indicating growth interruptions. Micritic growth layers characterize relatively rapid precipitation. The stable isotope (δ18O and δ13C) values suggest precipitation mainly from meteoric water and reflect the effect of the seawater by wash over or splash action in the stalagmite sample of Guvercinlik Cave located at sea level. The small variations in the δ18O and δ13C values are mainly controlled by amount of rainfall due to the seasonal changes and also input of seawater. Rainy periods are characterized by the relatively more negative δ18O and δ13C values and low contents of trace elements. Sea water input significantly increases the δ18O, δ13C, Na2O, MgO, Sr and Ba values.