Occurrence and origin of the zoned microgranular enclaves (MEs) within the Cretaceous granite in Taejongdae, SE Korea

Schedule of Mafic to Hybrid Magma Injections Into Crystallizing Felsic Magma Chambers and Resultant Geometry of Enclaves in Granites: New Field and Petrographic Observations From Ladakh Batholith, Trans-Himalaya, India

“…A large fine grained circular composite enclave (Figure 4D) lacks zoning. Zoned enclaves are commonly formed either by internal differentiation mechanism or multiple magma mixing and mingling events from magma source to emplacement level (Castro et al, 1990;Zhang et al, 2014;Zhang et al, 2016) or in two different, deep and shallower, magma chambers (Adam et al, 2019). However, the observed composite enclaves (Figure 4D) appear to have formed in an open felsic magma chamber that was essentially recharged intermittently by mafic to hybrid magmas pooled just below the felsic magma chamber (Figure 11), as similarly suggested for the origin of composite and other types of enclaves found in the granites of western Ladakh Batholith (Kumar, 2010a).…”

“…The similar ages, chemical, and isotopic signatures of enclaves and host granites have been interpreted in various ways. Some favor the cogenetic relation between the enclave and host granites (e.g., Pin et al, 1990;Shellnut et al, 2010) whereas some argue their derivation from common crustal sources (e.g., Güraslan and Altunkaynak, 2019;Lu et al, 2020); and some advocate mafic-felsic magma mixing, mingling, chemical modification, and isotopic re-equilibration at varying degrees responsible for their partial to nearly equivocal chemical and isotopic features (e.g., Holden et al, 1987;Eberz and Nicholls, 1990;Elburg, 1996;Kumar and Rino, 2006;Adam et al, 2019). The geochemical and isotopic features do not provide unambiguously a viable model of enclave origin.…”

“…The enclaves may also enclose xenoliths and are considered to be double enclaves (Didier, 1987), however, large enclaves can enclose several other smaller enclaves, which can be referred to as composite enclaves (e.g., Kumar, 2010a). Zoned enclaves with different cooling history are also reported in the granites (e.g., Adam et al, 2019).…”

Deciphering Magmatic Evolution through Zoned Magmatic Enclaves and Composite Dikes: An Example from the Late Cretaceous Taejongdae Granite in Busan, Korea

“…The Taejongdae granite, developed in the southeastern part of the Korean Peninsula, contains a distinctive pattern of magmatic enclaves (zoned MEs) made up of multiple different rock zones [16]. The zoned MEs in the Taejongdae granitoid may indicate the magmatic processes that occurred before the intrusion of the granitic pluton in the study area [17].…”

“…The zoned MEs in the Taejongdae granitoid may indicate the magmatic processes that occurred before the intrusion of the granitic pluton in the study area [17]. The first comprehensive petrographic and geochemical study for the Taejondae granitoid and its unique zoned MEs were conducted [16]. In addition, they examined amphibole chemistry within the zoned MEs and the host granite to understand the dynamic process and temperature change during the magmatic evolution.…”