Here are some references to Porphyry Deposits in the Ongkang...

Here are some references to Porphyry Deposits in the Ongkang area...nothing about peat though! sorry john


In addition, these porphyry-related gold deposits are localised along the NE Kalimantan Suture where it is cut by NNW striking arc normal structure. At Baroi, the wide circular feature is similarly cut by a series of subparallel, NNW trending arc normal faults, along which are also aligned the Mansur prospect to the north and the Tumbang Huoi prospect to the south.

The Ongkang gold deposit and other prospects in the Masupa Ria district to the south of KSK?s CoW are aligned along these NNW arc normal structures.

Many world class porphyry copper deposits, such as Batu Hijau and Panguna (PNG), are hosted within high level intrusions which have been emplaced at the intersection of large plutons and cross-cutting regional structures. The geological setting of southern Baroi is very similar to these deposits. The host lithologies at Baroi consist predominantly of andesite volcanic rocks into which have been emplaced monzonite and dacite porphyry intrusions at the margin of a large granodiorite pluton where it is cut by the regional NE and NNW structures (Figure 2