FEATURES OF THE LITHOGENESIS OF PALUDAL TUFA IN THE ZUBRA RIVER BASIN

Abstract

A study of paludal tufa in the Zubra river basin has been conducted. The organic remains within paludal limestone tufаs were analysed, paleoecological reconstruction of their formation conditions was carried out for the first time. Additionally, the study of the current anthropogenic transformation of the travertine body has been examined. Only one travertine massif, approximately 1 hectare in size, remains in the Zubra River basin at present. It is hardly damaged by human activity and consist of an amorphous accumulation of fragments of various shapes and sizes with variable coloration, represented by two main lithofacies: phytohermal and microdetrital tufa. Phytoherms are dominated by the remains of sedge and grass plant species, whose living stems formed the framework of the deposits. Microdetrital tufas, formed mostly from calcified remains of highly decomposed fallen leaves of trees and dead parts of herbaceous plants, are characterized by a homogeneous porous structure, in which the primary organic substrate is weakly discernible. A distinctive feature of the studied tufa formations is the presence of numerous ferruginous nodules, represented by randomly distributed ore masses, nest-like iron concretions, and areas with iron inclusions. The conducted researches confirm that the tufa deposits in the Zubra River basin are remnants of carbonate (alkaline) fens, which disappeared due to active and prolonged anthropogenic transformation of the area. The specific vegetation, low water flow, shallow depth, and the presence of bicarbonate-calcium spring waters facilitated the formation of significant deposits of calcareous tufa. Despite the fact that the discovered travertine deposits with iron ore inclusions have been inactivated due to anthropogenic interference and the alkaline bog is 'dead,' we consider the location we found near the Krotoshyn village to be unique, given its historical, aesthetic, and most importantly, scientific value. The tufa body requires conservation and should be designated as a local geological nature monument, as well as being subject to further in-depth research.