Petrography of lamprophyres of the Endegechu area of the Yana-Adycha tin ore region

The article considers the features of the petrographic composition of the lamprophyre dyke; attributed to the kHunkhadi complex of Late Cretaceous age; established on the Endegechchu hill in the Yano-Adycha tin ore region located in the Adycha tectonic zone. The rocks have a porphyry structure; and mineral formations of their own magmatic stage; magmatic; metasomatic and late hydrothermal-metasomatic substitutions are isolated in their composition. A characteristic feature of these rocks are spherulites of concentric-zonal structure; covered with a shell of scaly or lamellar graphite; depending on the size of the spherulites; evenly distributed throughout the rock; which were studied for the first time and have not been established in other igneous rocks widely developed in the area. The study of spherulites is an important petrological task; which makes it possible to identify the mechanisms of their formation and causes; can indicate the conditions of formation and sources of matter of the rocks containing them. The morphology of graphite; its distribution and the nature of its relationship with surrounding minerals are also very informative for establishing the primary nature of graphite and epigenetic changes in host rocks as a result of various hydrothermal-metasomatic processes; which is possible due to the ability of carbonaceous matter to redistribute in the rock when exposed to various forces; rather than being removed from it. 

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