Rokan basin

province of Indonesia

Riau (Jawi: ) is a province of Indonesia. It is located on the central eastern coast of the island of Sumatra, and extends from the eastern slopes of the Barisan Mountains to the Malacca Strait, including several large islands situated within the Strait. The province shares land borders with North Sumatra to the northwest, West Sumatra to the west, and Jambi to the south, and a maritime border with the Riau Islands and the country of Malaysia to the east. It is the second-largest province in the island of Sumatra after South Sumatra with a total land area of 93,356.32 km², and an estimate

regency in North Sumatra Province, Indonesia

regency in West Sumatra Province, Indonesia

river in Riau, Indonesia

regency in Riau Province, Indonesia

regency in Riau Province, Indonesia

Bagansiapiapi or simply known as Bagan () is a city in Riau province on the island of Sumatra, Indonesia. The city is the capital of Rokan Hilir Regency in the province and is located on the east coast of Sumatra, on the Rokan River delta across the strait west of Malacca and near Dumai.

river in Riau, Indonesia

river in Riau, Indonesia

Sarik-Gajah are two pyroclastic cones right at the equator line on Sumatra island, Indonesia. The first cone is Sarik, an andesitic/basaltic vegetated cone. The other is andesic-dacitic Gajah cone, 10 km south-west of the first one and it contains lava flow. No was eruptive history ever recorded from this volcanic complex.