Part of the research was financially supported by the European Regional Development Fund: European Union & Republic of Slovenia, Ministry of Education, Science and Sport (2017-2020; research programme OP20.01261), by the Slovenian Research Agency research core funding Geography of Slovenia (P6-0101) and Infrastructure Programme (I0-0031), by the scholarship of the Scientific Research Centre of the Slovenian Academy of Sciences and Arts for research work in Australia, and by the Australian Speleological Federation Karst Conservation Fund. TanDEM-X data was provided through approved science proposals DEM_GEOL1589 and DEM_GEOL2288.