GEOLOGICAL ASPECTS OF MALAYSIA

Outline of Malaysian Geology The country comprises five major geological terranes (Figures 1 & 2).

Figure 1 Figure 2	1.	The Western Belt of Peninsular Malaysia (to the west  of the Titiwangsa mountain range) containing the  oldest known rocks  (Middle Cambrian or earliest Paleozoic) in the country.
	2.	The Core region (also known as part of Sundaland)  consisting of the rest of Peninsular Malaysia, the  Sunda Shelf with the Malay and Penyu basins, and  westernmost Sarawak.
	3.	Central - Northern Sarawak and Western Sabah;  whose offshore parts include the Sarawak and  Northwest Sabah basin(s).
	4.	The Kinabalu zone, an up to 80 km wide belt of  chaotic deposits and fragments of an ancient ocean  floor. This geological suture zone is considered to  mark the remnant of a once-open ocean basin that  became closed some 25 million years ago.
	5.	Eastern Sabah that has many geological features  (and perhaps also biogeographical evidence)  indicating an origin near the eastern Asia continent.

ORIGIN While the Core region is considered to have been in its present position since a distant geological past, the other geological terranes had more dynamic histories. The Western Belt contains evidence of an older ice age that was characteristic for the southern continents, the so called Gondwana super continent. Fossils suggest that the Western Belt and adjacent parts of Sumatra and southern Thailand were once attached to Gondwana, possibly to the Northwest of Australia (Figure 2). Eastern Sabah may have been attached to the Asian continent (near Hong Kong?) and by geological plate-movements Eastern Sabah became sutured to greater Borneo. Central-Northern Sarawak and Western Sabah came into existence by -what geologists call- continental accretion or growth of the Southeast Asian landmass.