3-4-1-Geographical position and condition
Sabalan Volcano is to west Nagorno-Su Valley, north-west of Ardabil, the beginning and towards the east - west and a width of approximately 48 km to 60 km from Qushadagh to south Ahar, continues. Sabalan volcanic cones of lava Astratvvlkanvst that the range of that cover 1200 square kilometers.
2-4-3- Sabalan volcano geology and lithology
Sabalan volcano cone has a big central structure which is located on a horst system with a trend of W-E. Didone and Jouns (1976) have known as age of Plioquaternary for Sabalan Volcano and some volcanic activities from Sabalan to Miocene while Babakhani, lesquich and Rhio (1369) believe that first lava flow in Sabalan are located on Tuffi and Alyar conglomerates which are equivalent to early Quaternary deposits in Meshkin, Shahr Basin. In other words , mentioned volcanic activity is initiated during early Quaternary times it is continued to late glacial period (20 to 70 thousand years Agol Doiden and Joumen have divided Sabalan Activity into three parts:
1- Old Sabalan Lava flows lava flows which have been caused in this step embed most portion of Sabalan Mount : Mentioned people have segment Ted this part into 5 steps but Babakhan: and Lesquich Verio summary them into three steps which are :A –Lower andesite which hove outcrop in northern and eastern sides .
B- Middle Trachy-Andesite which makes Sabalan volcano Main Part and it has extent in all of Sabalan Mount Ridges, C –Dacite lava flow which is ended in evolution of volcano strata before caldera.
2- Depression: in this central part, early structure is disrupted. Result of this event is creation of circular depression in diameter of 20 km. Contemporary to caldera Depression, some explosive eruptions have been occurred which has been composed of volcanoclastic materials.
Mechanism of this activity is explained as it has caused first not avalanches which transport some older fragments with is in glacial valleys .Then explosive materials eruption are contemporary to fall ignimbrite flow and thin pumice which is distributed in Savieh Valley and horrible explosion results in creation of big volumes of ash .
3- Domes and lava flows from Young Sabalan: after falling caldera, volcanic materials are exploded which cause highest part of central part. In this stage, there is with two conical and lava flows. In mentioned stage, some sulfur and volcanic activities from Sabalan have a composition of rhyolite to dacite and big point about these volcanic activities is sodium – bearing alkaline types of these rocks (map – 3-4 )(fig 2-4).