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在日本西南高知县足折岬的第三纪火成杂岩中发现了特殊的环斑花岗岩,这些环斑花岗岩与粗粒正长岩有密切的联系,后者以网状岩墙群侵入到辉长质岩块中。在环斑花岗岩与粗粒正长岩接触边界上,由于中—细粒花岗闪长岩的侵入,粗粒正长岩沿颗粒边缘和裂隙分解成单个晶体或晶体碎片,而这些花岗闪长岩含有环斑花岗岩的基质成分。花岗闪长岩体中的钾长石晶体成其碎片熔蚀成卵形,无规则地分布,而且为薄片斜长石(An15—25)包覆。这些薄片随基质流动构造的形成而加厚. 环斑斜长石呈卵形,直径1～3cm,有时沿基质的流线平行或似平行分布。其内核常为一不具双晶或有双晶的钾长石晶体,而且常伴有石英和斜长石的晶体,而外壳大部分由很多细小的树枝状斜长石和斜长石晶隙间蠕虫状石英组成,它们甚至比基质还细小.在基质极度细小的地方,环斑长石的壳很薄,甚至没有。在同一岩石中,环斑长石和其他卵形体共存,诸如斜长石(被钠长石或钾长石包覆)、石英(被角闪石和斜长石包覆)、角闪石(被角闪石和黑云母的集合体包覆)和黑云母。在岩相学和化学特点上,这些卵形体的内核矿物与粗粒正长岩的矿物相似. 从上面描述可见,该环斑花岗岩的形成是粗粒正长岩发生结晶及随后的花岗闪长岩侵入的结果.粗粒正长岩分离出来的钾长石晶体沉浸到花岗闪长岩岩浆中,其边部遭受侵蚀,形成卵圆状晶体。新结晶的树枝状斜长石被吸附在钾长石周围,然后,树枝状斜长石之间的空隙被石英充填. Hibbard(1981)对其他很多地区环斑花岗岩的成因研究也得出了与岩浆混合作用有关的相似认识.
In the Tertiary igneous rocks in the Ashizuri Misaki, Southwestern Kochi, Southwestern Japan, special ringed granites have been found, which are closely related to the coarse-grained syenite, which intrudes into the gabbro In the rock mass. On the contact boundary between ringed granite and coarse-grained syenite, coarse-grained syenite breaks down into single crystals or crystal fragments along grain boundaries and fissures due to the intrusion of medium-fine granodiorites, and these granite flashes The feldspar contains the matrix composition of the ringed granite. The K-feldspar crystals in the granodiorite melt into ovoid, irregularly distributed fragments, and are covered by lamellar plagioclase (An15-25). These laminae are thickened with the formation of the matrix flow structure.The ring-finger plagioclase is oval in shape with a diameter of 1 to 3 cm, sometimes parallel or approximately parallel to the streamline of the substrate. Its core is often a non-twin or dual-decker potash feldspar crystals, and often accompanied by quartz and plagioclase crystals, and the shell is composed of many small dendritic plagioclase and plagioclase intergalactic worms Like quartz, which are even finer than the matrix, and where the matrix is extremely small, the ring-shaped plagioclase shell is thin or nonexistent. In the same rock, ring-shaped plagioclase coexists with other ovoid bodies such as plagioclase (coated with albite or potash feldspar), quartz (encrusted with amphibole and plagioclase), hornblende Amphibole and biotite aggregates coated) and biotite. In terms of petrography and chemistry, the core minerals of these ovoid bodies are similar to those of coarse-grained syenite, and as can be seen from the above description, the ring-shaped granite is formed by the crystallization of coarse-grained syenite and subsequent granodiorite As a result of intrusion of feldspar, the K-feldspar crystals isolated from the coarse-grained syenite have been infiltrated into the granodiorite magma and the edges have been eroded to form oval-shaped crystals. The newly crystallized dendritic plagioclase is adsorbed around the potash feldspar, and the interstices between the dendritic plagioclase are then filled with quartz.Hibbard (1981) also studied the genesis of the macular granitic rocks in many other areas Similar Understanding of Magma Mixing.