000			03495nam a2200181 4500
008			160321t1978 my 000 0 eng
082			_a555.9 JON
100			_bC. R. Jones
245			_aThe geology and mineral resources of Perlis, North Kedah and the Langkawi Islands.
250			_aDistrict Memoir 17
260			_aKuala Lumpur: _bGeological Survey Malaysia, Ministry of Primary Industries Malaysia, _c1978.
300			_aill. 257 p. (Included references and index).- 25.3 cm.- _eAccompanying material: Geological Map ( Perlis: Sheet 2E/5, Kedah: Alor Star & Pulau Raya.- Sheet 2E/13 & 2E/14, Perlis/Kedah: Kangar.- Sheet 2E/9, Jitra Sheet 2E/10, 2E/6, Pulau Langkawi Sheet 150.- Scale 1 : 63,360) & Sections Across ( Kedah: Sheeet 150 -Langkawi, Perlis/Kedah Sheet 2E/5, 2E/6, 2E/9 & 2E/10)
500			_aPrice: RM 50.00
942			_2ddc _h555.9 JON
520			_aSummary: Apart from its significance as a minor tin producer, the region comprising Perlis, north Kedah and the Langkawi Islands is of particular interest geologically on account of the wide range of rock formations present. Workers in the early decades of the century outlined the geology and structure of the area but because of the reconnaissance nature of these investigations much of the stratigraphy and structure were misunderstood. The discovery of abundant diagnostic fossils and the acquisition of detailed structural data during the present survey have completely revolutionised the earlierstratigraphical interpretations. in additionto the previously identified Carboniferous, Permain and Trassic strata, rocks of Cambrian, Ordovician, Silurian and Devonian age have now been identified. the succession commences with late Cambrian arenities which pass conformably into a predominantly calcareous sequence of Ordovician to lower Devonian age. The unconformably overlying pre- and syn-orogenic formations comprise a wide variety of clastic sediments and limestonesranging from Upper Devonian to Triassic in age. Granite was intruded at epizonal levels towards the close of the Cimmerian earth movements probably in late Triassic times. Tin mineralization in north Perlis and in north Kedah and sulphide mineralization in the Langkawi Islands are related to this igneous event. Orogenesis was accompanied by large scale, pre-granite thrusting and post-granite faulting. Loosely consolidated superficial formations of late Tertiary, Pleistocene and Recent age cover the consolidated and crystalline rocks over large areas and are responsible for much of the mineral wealth and agricultural and groundwater potential of the region. Tin is the only important mineral to have been exploited in the region although ornamental stone and agricultural phosphates are worked on a small scale. The tin mining industry, although never contributing more than 0.7 per cent to the total tin-ore produced annually in Malaya, is interesting on account of the unusual occurence of the deposits and the way in which they are mined. The industry, centred in north Perlis, works pockets of alluvium located in limestone caves deep in the Setul Boundary Range. Apart from north Perlis the region is not thought to be rich in other mineral deposits although a sulphide zone of potential interest occurs in the Langkawi Islands.
648			_xGeology _yMalaysia _zPerlis, North Kedah and Langkawi islands
650			_xMineral Resources _yMalaysia _zPerlis, North Kedah and Langkawi Islands
999			_c33 _d33