Pliocene crater lake deposits and soft sediment deformation structures associated with a phreatomagmatic volcano, Pula maar, western Hungary.

Pula maar is a Pliocene eroded, phreatomagmatic volcano, part of the Mio/Pliocene Bakony-Balaton Highland Volcanic Field.The remnant of the maar consists of a (1) distinct depression with a thick alginite, lacustrine laminite infill interbedded with coarse grained lapilli tuffs, (2) a narrow belt of a primary pyroclastic unit (tuff ring) in the marginal zone of the depression (erosion remnant of the tuff ring) and, (3) a reworked coarse-grained volcaniclastic unit in the marginal zone. .Paleo-earthquakes associated with ongoing nearby volcanic eruptions and/or large volume debris flows initiated by crater wall collapses into the maar crater lake are inferred to be responsible of formation of soft sediment deformation of fine-grained volcaniclastic sediments.