Lake Van

Abstract

Lake Van is the largest soda lake in the world. It is a terminal lake, surrounded by mountains rising to 3500 m a.s.l. The Lake Van Basin is divided into three geological and morphological units: (1) the mostly metamorphic Bitlis Massif pertaining to the Bitlis suture zone to the south-west; (2) Mesozoic and Tertiary rocks (carbonates and volcanics) between the lake and the Turkish-Iranian border, and (3) volcanoes and volcanic products extending from the west to the north-east of the lake. The variety of the geomorphological landscapes around the lake is exceptionally high, with (i) some of the most impressive dormant volcanoes of Turkey; (ii) young (Late Pleistocene to recent) volcanic features such as a lake-filled caldera on top of the beheaded Nemrut Volcano, the solitary Suphan Volcano (the "Tushpa" God of the Urartians which dominates the lake by >1000 m), the fresh basaltic lava flows of the Tendurek Volcano, etc.; (iii) extensive lake terraces filling large valleys where they record impressive variations in lake level at least since the last 200 ka; (iv) travertine mounds associated with fault lines and river valleys; (v) karstic landscapes in the Bitlis Range and in the Tertiary limestones to the north-west, where they are covered by Nemrut ignimbrites and Suphan basalt and obsidian flows; (vi) glacial imprints on the summits of the Bitlis Range and of the Suphan; (vii) active landslides in marine sediments forming the slopes in the south-eastern basin; (viii) strong influences of tectonics on the relief, etc. Like in all Eastern Anatolia, high altitude pastures attract since millennia long-distance migrations of sheep herds seasonally switching between the southern plateaus in Syria and Iraq in winter, and Eastern Anatolia and the Caucasus in summer.