Some aspects of southern granitoid complex and tin mineralization in the northern part of Bangka, Indonesia


Author : R.Soeria-Atmadja, D. Darda & D. HasanuddinPublication : Bulletin of the Geological Society of MalaysiaVolume : 19Page : 349-367Year : 1986


Description

Bulletin of the Geological Society of Malaysia, Volume 19, April 1986, pp. 349 – 367

 

Some aspects of southern granitoid complex and tin mineralization in the northern part of Bangka, Indonesia

R. SOERIA-ATMADJA*, D. DARDA** and D. HASANUDDIN*

*Dept. of Geology, Institut Teknologi Bandung, Jalan Ganesa No. 10, Bandung, Indonesia

**Geological Research & Development Centre, Jalan Diponegoro No 57, Bandung, Indonesia

 

Abstract: The southern granitoid complex in this study refers to granitoid exposures in the areas of Menumbing-Tempilang along the southern coast and Pelangas-Kelapa further north, south of Kelabat intrusive complex. Petrographically the rocks consist of medium to coarse grained porphyritic monzogranite, syenogranite and monzonite. The main minerals are quartz, K-feldspar, plagioclase and biotite.

In a southerly direction from Pelangas-Kelapa to Menumbing-Tempilang complex, the following changes have been observed, viz. disappearance of hornblende, increase of myrmekitic, granophyric and micrographic textures, development of replacement-type microperthite, increase of Rb/Sr, Nb, F, Sn, normative corumdum, and decrease of CaO/MgO and Ba.

Nearly all granitoids plot in the S-type field; generally they show low magnetic susceptibility suggesting Ilmenite Series. Tin mineralization in the granitoid and country rocks took place mostly along west northwest, north northeast and nearly north-south directions, and they seem to be more related to Late Triassic deformation.

https://doi.org/10.7186/bgsm19198626