Narrow north trending units of Upper Triassic limestone occur to the west of the Iskut River and north and southeast of Hankin Peak. This unit, made up of discontinuous beds and lenses of limestone, is widespread in the Telegraph Creek and adjacent map areas. Souther (GSC Paper 71-44) describes this unit as a "thin-bedded, flaggy, fetid limestone with much interbedded shale and siliceous silt. Locally it is thick-bedded or massive." The unit may range from less than a metre to more than 100 metres in thickness. The massive facies is fossiliferous containing a reefoid fauna of mainly corals and bryozoa.