Lake Baikal is in a rift valley, created by the Baikal Rift Zone, where the Earth's crust is slowly pulling apart. At 636 km (395 mi) long and 79 km (49 mi) wide, Lake Baikal has the largest surface area of any freshwater lake in Asia, at 31,722 km2 (12,248 sq mi), and is the deepest lake in the world at 1,642 m (5,387 ft). The bottom of the lake is 1,186. 5 m (3,893 ft) below sea level, but below this lies some 7 km (4. 3 mi) of sediment, placing the rift floor some 8–11 km (5. 0–6. 8 mi) below the surface, the deepest continental rift on Earth. In geological terms, the rift is young and active – it widens about 2 cm (0. 8 in) per year. The fault zone is also seismically active; hot springs occur in the area and notable earthquakes happen every few years. The lake is divided into three basins: North, Central, and South, with depths about 900 m (3,000 ft), 1,600 m (5,200 ft), and 1,400 m (4,600 ft), respectively. Fault-controlled accommodation zones rising to depths about 300 m (980 ft) separate the basins. The North and Central basins are separated by Academician Ridge, while the area around the Selenga Delta and the Buguldeika Saddle separates the Central and South basins. The lake drains into the Angara tributary of the Yenisei. Notable landforms include Cape Ryty on Baikal's northwest coast.