The Luswishi Dome forms part of the Neoproterozoic Lufilian Arc which hosts copper-cobalt ores of the Central African Copperbelt. We report new data from a study that combines observations from drill core logging, petrographic and chemical analyses, geothermobarometry and phase equilibria modelling. Drill core logging identifies lithostratigraphic units which are partially correlated with the Katanga Supergroup based on the occurrence of regional markers. The Nguba Group constrained by the presence of glacial tillite includes variably deformed, carbonaceous shales, and carbonates. An underlying sequence of quartzites, metapelites, calc-silicates, meta-sandstones, shales, dolomites and gabbros is partially correlated with the Roan Group. Overprinting relationships of structures in drill core provide evidence for possible polyphase deformation. Early deformation generated folds which were overprinted by faults and later by brecciation caused by hydrofracturing during later deformation, and subsequently metasomatism. Petrographic examinations reveal porphyroblast-inclusion-matrix relationships which indicate that the area experienced at least two penetrative ductile deformation events, D1 and D2, which are in turn overprinted by brittle structures at D3 and later phases. Thermobarometry calculations identify peak metamorphic conditions of 580–600 °C with maximum pressures of ~7 ± 1 kbar. Integrating thermobarometry with pseudosection modelling allows reconstruction of clockwise P-T-d paths consistent with consumption of epidote, chlorite, muscovite, quartz and low Ca-plagioclase to form biotite, garnet, high Ca-plagioclase and aluminosilicates. These observations suggest Barrovian intermediate P/T-type metamorphism which can be attributed to a tectonic scenario of burial under geothermal gradients of ~20–25 °C/km prior to uplift and erosion. These data complement previous models of regional metamorphism by crustal thickening during the Lufilian orogeny.

Luswishi Dome 是新元古代 Lufilian Arc 的一部分，该弧包含中非铜带的铜钴矿。我们报告了一项研究的新数据，该研究结合了钻芯测井、岩相和化学分析、地热气压测量法和相平衡建模的观察结果。钻芯测井可根据区域标记的出现识别与加丹加超群部分相关的岩石地层单元。受冰碲岩存在限制的 Nguba 群包括变形的碳质页岩和碳酸盐岩。石英岩、变泥质岩的潜在序列、钙硅酸盐、变质砂岩、页岩、白云岩和辉长岩与 Roan Group 部分相关。钻芯中结构的叠印关系为可能的多相变形提供了证据。早期变形产生的褶皱被断层覆盖，后来被后期变形过程中的水力压裂引起的角砾化作用以及随后的交代作用所覆盖。岩相学检查揭示了卟啉-内含物-基质关系，这表明该区域经历了至少两次穿透韧性变形事件，D1 和 D2，它们依次被 D3 和以后阶段的脆性结构套印。热气压计算确定峰值变质条件为 580–600 °C，最大压力为 ~7 ± 1 kbar。将热气压测量与假截面建模相结合，可以重建与绿帘石、绿泥石、白云母、石英和低钙斜长石消耗一致的顺时针PTd路径，以形成黑云母、石榴石、高钙斜长石和铝硅酸盐。这些观察结果表明，巴罗维亚中间P/T型变质作用可归因于在隆起和侵蚀之前地温梯度约为 20-25°C/km 下埋藏的构造情景。这些数据通过地壳增厚补充了先前的区域变质作用模型 在卢菲利亚造山运动期间。