Kejadian dan implikasi korok-korok pegmatit sinplutonik di granit Gunung Jerai, Kedah (Occurrence and implication of synplutonic pegmatite dykes in the Gunung Jerai granite, Kedah)


Author : T. T. KhooPublication : Bulletin of the Geological Society of MalaysiaVolume : 8Page : 117-120Year : 1977


Description

Bulletin of the Geological Society of Malaysia, Volume 8, Dec, 1977, pp. 117 – 120

 

Kejadian dan implikasi korok-korok pegmatit sinplutonik di granit Gunung Jerai, Kedah

(Occurrence and implication of synplutonic pegmatite dykes in the Gunung Jerai granite, Kedah)

T.T. KHOO

Jabatan Geologi Universiti Malaya, Kuala Lumpur.

 

Abstract: Some pegmatite dykes in the Gunung Jerai granite at Merbok, Kedah have been found to be sheared and displaced. The shear zones, however, have been annealed by the granite which indicate that the dykes are synplutonic and therefore coeval with the granite. At the same outcrop a few of the pegmatite dykes have swollen parts with circular to elliptical cross-sections. These bulbous parts are probably formed by upwelling of pegmatitic materials into a still viscous granite host.

The recognition that the granite and pegmatite are coeval may help in the interpretation of geochronological data on the granite and pegmatite presented by Bignell (1972).