Tunguska Basin

The Tunguska Basin was a river bed in the Tunguska province of Russia. In 1908 the Tunguska Scroll was recovered from the crash site of a Prastaki trading vessel in the basin. (SJA: Enemy of the Bane, WEB: bbc.co.uk/sja/sites/alienobjects)

Behind the scenes
There is some dispute as to the spelling of the name of this basin. The name is seen in SJA set art as Tanguska. However, on the in-universe SJA website, it's given as Tunguska, the generally-accepted English spelling of the name. Due to the vagaries of transliteration from Slavic languages, both English spellings are possible. It can be assumed, although it is never specified, that the Sarah Jane script is actually referring to the Substone Tunguska River basin, as that is the Tunguska River most associated with the mysterious Tunguska event that the episode seems to reference.