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基德火山杂岩是由太古代长英质火山岩和次火山岩组成.长英质岩夹有沉积岩并和科马提岩质超基性岩相接触.大型闪长质深成岩体侵位于流纹岩中。而杂岩上覆有更年轻的玄武岩.影响基德火山杂岩岩性的交代事件包括硅化作用,广泛的 CO_2交代作用(碳酸盐)、钾交代作用(绢云母-铬云母)和绿泥石及少量碳酸盐蚀变.岩石学证据及稳定同位素和气液包裹体研究结果是一致的,认为硅化作用和早期碳酸盐蚀变是同火山期的,因此和成矿作用有关.在其后广泛的钾交代作用期间.绢云母交代流纹岩,在超基性岩中则为铬云母.尽管绿泥石在钾交代作用之后形成,但在网状裂晾中可以发现,云母和绿泥石通常充填在同一组裂隙中.在钾交代作用和绿泥石蚀变期间,由磁铁矿-钛铁矿分解形成的热液金红石,经 Pb-Pb同位索测定年龄为2624±62Ma(95%置信度).因此,金红石比原生块状硫化物的矿化(2717±2Ma)年轻大约100Ma.绢云母和绿泥石脉中的硫化物细脉说明在这些较晚期事件中矿石重新受到活化作用.一般认为这一蚀变组合与矿化作用有密切联系。它和在苏必利尔省发现的与许多脉金矿床伴生的蚀变组合完全相同.最近对阿比蒂比亚省(subprovince)与金矿床伴生的云母和金红石进行测定,所得年龄与基德火山杂岩中金红石的年龄相当,因此,这一年龄应该记录着一次广泛分布的、影响矿化岩石的晚期热液事件.
The Kitti volcanic complex is composed of Archean, long-felsitic volcanic rocks and subvolcanic rocks, which have sedimentary rocks in contact with the komati-derived ultrabasic rocks, and large-scale dioritic plutons invaded rhyolite in. While the complex is covered with younger basalts.The metasomatism that affects the lithology of the Kit-delhi volcanics includes silicification, extensive CO 2 metasomatism (carbonate), potassium metasomatism (sericite-chrome mica) and chlorite And a small amount of carbonate alteration.The petrologic evidence and the stable isotope and gas-liquid inclusions research results are consistent, that the silicidation and early carbonate alteration is the same volcano, and therefore related to metallogenesis .After that During extensive K replacement, the sericite metamorphic rhyolites are chrome mica in ultrabasic rocks, and although chlorite was formed after potassium replacement, it can be found in the reticulated dike that mica and chlorophyll The rocks are usually filled in the same set of fractures, and the hydrothermal rutile, formed by the decomposition of magnetite-ilmenite, is 2624 ± 62 Ma (95%) measured by the Pb-Pb isotope during potassium metasomatism and chlorite alteration % Confidence) .Therefore, rutile is about 100 Ma younger than the mineralization of native massive sulphide (2717 ± 2 Ma). The fine vein of sulphide in sericite and chlorite veins indicates that the ore is reactivated in these later events It is generally accepted that this altered assemblage and mineralization close relationship. It is identical to the alteration assemblages associated with many vein gold deposits found in the province of Superior. Recent measurements of micas and rutiles associated with gold deposits in the subprovince province of Abidjan, The age of the rutile in the rock is quite comparable. Therefore, this age should document a widespread hydrothermal event that affects widely mineralized rocks.