Development and Zones of Subsidence Dolines in Case of Shore Shiftings of Regression, Transgression and Oscillation Types

Abstract

This study deals with the karstification of coastal covered karsts with the aim of looking for a relationship between sea level changes and feature development taking place on the covered parts of carbonate karsts. This relation is manifested by the fluctuation of karst water level that is controlled by the sea level. Through further studies, shore shiftings occurring during the time of various paleokarst feature assemblages can be established. The development of suffosion dolines and dropout dolines at subsurface water level is analysed. The pattern of coast zones with dolines is studied in three cases thus, on regressive coast at non-fluctuating water level (1), on transgressive coast at non-fluctuating water level (2), and at oscillating sea level at oscillating karstwater level (3). In the first case, a solution doline zone (and/or karren zone), a mixed or compound zone (with suffosion dolines and dropout dolines) and a suffosion doline zone develops landward. In the second case a suffosion doline zone develops (this may turn into a mixed zone) and during further subsidence, a filled doline zone develops which may expand at the expense of the suffosion doline zone (mixed doline zone). In the third case, close to the shore, in the glacial a dropout doline zone and a suffosion doline zone are separated. In the interglacial, a solution doline zone develops at the uncovered surface, at the outer, seaward part of the dropout doline zone dolines with lakes are formed, the development of suffosion dolines continues in the suffosion zone.