INFLUENCE OF GEOSTRUCTURAL CONDITIONS ON THE SPELEOGENESIS OF THE TRIESTE KARST (ITALY)
Dipartimento di Scienze Geologiche, Ambientali e Marine, Trieste University; Via E. Weiss 2,1- 34127 Trieste (Italy)
Dipartimento di Scienze Geologiche, Ambientali e Marine, Trieste University, Via E. Weiss 2,1-34127 Trieste (Italy)
Dipartimento di Scienze Geologiche, Ambientali e Marine, Trieste University, Via E. Weiss 2,1-34127 Trieste (Italy)
Dipartimento di Scienze Geologiche, Ambientali e Marine, Trieste University; Via E. Weiss 2,1- 34127 Trieste (Italy)
Abstract
SUMMARY. The Trieste Karst is a relative old karst that has been evolving for almost 10 million years: the initial superficial morphologies (planation surfaces which have evolved in the shape of polje system and deep collapse dolines) are difficult to distinguish. The cavities maintain rare primary morphologies filled by deposits, breakdowns and concretions, which at the same time modify other deep morphologies due to changes in the baseline level and adaptations to tectonic movements.
The comparison between structural setting of rocks and development directions of caves confirms the strict influence of geological-structural features on speleogenesis: the drainage network should have been mainly conditioned by the highest slope of the stratification (sometimes modified by intersections following a similar direction between strata and fracture plains). Secondary influences regard the presence of "opened planes" and those related to intersection lines between opened plains due to tectonics or structural features.