Cave Forms and Origin of the Cave Pečina v Zjatih (Matarsko Podolje, Slovenia)

Abstract

Jama leži v Matarskem podolju, v SZ delu Slovenije. Okolico sestavljajo apnenci ter apnenčaste breče kredne starosti. Njen vhodni del je udornega nastanka in leži v večji vrtači, jama pa se konča s podorom pod drugo vrtačo. Nad osrednjim delom jame je tudi manjša vrtača; posledica je, da je v tem delu obilnejša siga. Očitne so poškodbe zaradi zmrzali, ki segajo globoko v jamo; v vhodnem delu so značilni pojavi plazenja krioklastičnega grušča. Jama je sprva nastajala v freatčnih, nato pa v epifreatičnih pogojih. Izračunan nekdanji pretok kaže na veliko količino vode.

Cave lies in Matarsko podolje, in southwestern part of Slovenia. Surrounding beds are composed of limestones and limestone breccias of Cretaceous age. In the vicinity there are many dolines and collapse dolines. The entrance and final part of the cave are situated directly under the big dolines. Because of the small doline, which can be found above the middle part of the cave, there are many flowstone features. Obvious damages due to the freezing and thawing are found along the most part of the cave, at the entrance there is a lot of cryoclastic gravel. Cave began to form in phreatic and later in epiphreatic conditions. Palaeoflow discharge indicates great amount of water.