The Protolith Reconstruction Of New Discovery-Ketubong Deposit In Ulu Sokor, Malaysia

Ulu Sokor gold mine field is located in the north of the Central gold metallogenic belt, numerous Gold and polymetallic ore deposits (points) have been discovered in this area, New Discovery-Ketubong gold depsit is in the south of this gold mine field. The Ore-bearing stratum of this deposit is a set of epimetamorphic rocks including Phyllite,Crystal tuffaceous phyllite, Metamorphic crystal tuff and crystalline limestone,the formation of the depsit is closely associated with shear zone.On the basis of the character of microphysiography, lithochemistry, trace element and rare earth element, the research of the protolith reconstruction has been conducted in the Ore-bearing strata of New Discovery-Ketubong deposit. According to the result, the original rock of Phyllite, Crystal tuffaceous phyllite and Metamorphic crystal tuff is mainly constituted of volcano Tuff (Andesitic) with inequality argillaceous sediments, In addition, the proportion of these argillaceous sediments in original rock decreases gradually from Phyllite to Metamorphic crystal tuff. However the original rock of crystalline limestone is belongs to the normal Calcium carbonate.Based on the result of the analysis of rock-forming element and trace elements, it has been proved that these epimetamorphic rocks are identified as the high value of ΣREE, LREE and LREE/HREE, the concentration of Rb, k and Th, and the obvious loss of the high field strength element including Nb, Ta, P, Ti. It has been postulated that it has the typical features of island arc volcanic and these samples are limited to the area between the activities continent edge and island arc environment range, which can been seen in the figure of differing from district tectonic environment. Combined with the tectonic environment, it can be easily concluded that the epimetamorphic rock original Rock formed in the area brings together continental margin volcanic arc environments.To sum up, the lithogenous material of the Ore-bearing stratum in the study area is derive from a set of Andesitic magma with some up-crust materials, resulting from the invasion after the Ocean crust deep melting, finally formed by the volcanic ejection. This stratum constitutes of the gold-bearing layer in this area. Based on the role of regional metamorphism, the granitic magma invading during the later ore-forming stage, provides the enough heat to make gold in the formation continually activated, and then as the metamorphic hot liquid migrate to those favorable constructed parts and finally deposit.