Geomorphological assessment of the Beciu mud volcano terrain, Eastern Carpathians, Romania

Abstract

Mud volcanoes are widespread geological and geomorphological structures that are usually associated with folded sedimentary deposits bearing hydrocarbons. A significant number of mud volcanoes and gas seepages occur both in the extra-Carpathian area and the intra-Carpathian area in Romania. The most famous region in terms of number, geomorpho-diversity, and area surface of mud volcanoes is the Berca-Arbănași system, which is related to an anticline that belongs to the Buzău Subcarpathians division located in the southern part of the Eastern Carpathian belt, Romania. In this paper we present the results of geomorphological assessment of mud volcanoes from Beciu site that belongs to the Berca-Arbănași system, based on field surveys and drone mapping. The Beciu mud volcano terrain resembling a dome plateau has an area of a half hectare whereon are scattered around 50 active mud vents and gas vents, with a relatively quiescent expulsion of gas, water, and mud. In the area of Beciu site typical features of classical mud volcanoes were identified, as well as peculiar microforms that develop on the mud flows. Badland morphology has formed by the surface water runoff erosion of clay sediments outcropping in the peripheral area of the mud volcano terrain. Although the Beciu mud volcano site is not a protected area, its conservation status is favorable and no anthropogenic threats and pressures have been identified at present.