The late Neoproterozoic granitoids of Gebel Um Shager and Gebel Hamadat, Central Eastern Desert of Egypt, in addition to Paleozoic trachytes of both areas were discriminated using Landsat-8, and Sentinel-2 dataset. Band rationing and Principal Component Analysis techniques were applied. The studied granitoids represent the extreme end-members of the subduction-related I-type calc-alkaline granitic magmas (primitive to more evolved varieties) that developed over a long period of time. These granites were extruded by Paleozoic intra-plate trachytes. Petrography and petrogenesis of these rocks were dealt with and discussed. The Um Shager Older Granitoids (calcic tonalite to quartz monzodiorite) represent poorly differentiated metaluminous magma characterized by very low Rb/Sr ratio ∼0.07. Evolutionary, they follow the calc-alkaline subtype trend and most probably were originated from parent gabbroic magma by fractional crystallization in a volcanic arc setting. On contrary, the Hamadat Younger Granites represent alkali calcic magma which was developed in post-collision setting. They comprise evolved subsolvus metaluminous syenogranite and alkali feldspar granite. Evolutionary, they follow the subalkaline subtype trend. Crystallization courses of both syenogranite and alkali feldspar granite were started by alkali feldspar, followed by cotectic crystallization of alkali feldspar and quartz and ended by eutectic crystallization of all quartzofeldspathic minerals. The trachytes represent intra-plate continental alkaline magmatism. The Um Shager trachytes were developed at local extension zones, while the Hamadat trachytes were originated during global continental rifting system. Syenogranite, alkali feldspar granite and trachytes are important sources of alkali feldspar, which has wide spectrum applications in industry and agriculture.

使用 Landsat-8 和 Sentinel-2 数据集区分了埃及中东部沙漠 Gebel Um Shager 和 Gebel Hamadat 的晚新元古代花岗岩，以及这两个地区的古生代粗面岩。应用了频带配给和主成分分析技术。所研究的花岗岩代表了长时间发育的与俯冲相关的 I 型钙碱性花岗质岩浆（原始到更进化的品种）的极端末端成员。这些花岗岩是由古生代板内粗面岩挤压而成。对这些岩石的岩石学和岩石成因进行了处理和讨论。Um Shager 较老的花岗岩（钙质英云长岩到石英二闪长岩）代表低分化的金属铝岩浆，其特征是 Rb/Sr 比率非常低，约为 0.07。进化的，它们遵循钙碱性亚型趋势，最有可能起源于火山弧环境中的分馏结晶的母辉长岩岩浆。相反，Hamadat Younger 花岗岩代表了在碰撞后环境中发育的碱性钙质岩浆。它们包括演化的亚溶解金属铝正长花岗岩和碱性长石花岗岩。进化上，它们遵循亚碱性亚型趋势。正长花岗岩和碱长石花岗岩的结晶过程均以碱长石开始，继之以碱长石和石英的共晶结晶，最后以所有石英长石矿物的共晶结晶结束。粗面体代表板内大陆碱性岩浆作用。Um Shager 粗面岩是在局部延伸区开发的，Hamadat粗面岩起源于全球大陆裂谷系统。正长花岗岩、碱长石花岗岩和粗面岩是碱长石的重要来源，在工农业中有着广泛的应用。