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在克罗克威尔矿区的钠质花岗岩及伴生的钠质片麻岩中产有钍钛铀矿矿化。野外工作、矿物学和化学资料证实,这种花岗岩是片麻岩经过高度变质期间的深熔作用而形成的。钠质花岗岩大部分属过铝质的,Na_2O含量高、K_2O,CaO、Rb、Ba、Sr和铁镁元素含量低,U、Th、Nb、Ce、Y和F的含量一般较高。许多地球化学参数在成分上继承了相似的钠质片麻岩,认为它的原岩是中-酸(碱)性序列的富方沸石火山-沉积岩受变质而来。重要的铀-钍矿化只限于破碎带和角砾岩带中。矿物组合为富石英、含氟金云母及少量的氟磷灰石、钠质斜长石、铌金红石、钍钛铀矿、独居石、白云母、绿泥石、电气石和萤石。其成因类似于所谓的斑岩铜矿和网脉状钼矿床。这种矿床是在钠质花岗岩类固相线以下的冷凝过程中,由于机械破裂和角砾岩的发育而形成的。
Thorium-bearing uranium mineralization occurs in the sodium granites and accompanying gneiss in the Rock Crocker area. Fieldwork, mineralogy and chemical data confirm that this granite is formed by deep-melting gneisses during highly metamorphic periods. Most of sodium-bearing granites are of the aluminous type, with high Na 2 O content and low contents of K 2 O, CaO, Rb, Ba, Sr and Fe-Mg elements and generally high U, Th, Nb, Ce, Y and F contents. Many geochemical parameters inherit in composition similar gneiss, which is believed to be metamorphous (zeolitic) volcanic-sedimentary rocks with meta-acid (alkali) sequence. Important uranium-thorium mineralization is limited to crustal and breccia zones. The mineral assemblage is rich in quartz, fluorophlogopite and a small amount of fluorapatite, plagioclase, niobium rutile, thorium-titanium uranium, monazite, muscovite, chlorite, tourmaline and fluorite. Its origin is similar to the so-called porphyry copper and reticular molybdenum deposits. This deposit was formed during the condensation below the solidification line of the sodium-type granite due to mechanical rupture and breccia development.