## 1 Introduction  
The East Kunlun Orogenic Belt (EKOB) is a significant key component of the East Tethys tectonic domain. The EKOB has preserved many extensive magmatic records from oceanic subduction events to continental collisional events during the Early Paleozoic [1, 2, 3, 4]. There are mafic-ultramafic rocks, granites, and HP-UHP (High pressure-ultrahigh pressure metamorphic rocks) metamorphic rocks that developed from the Early to Late Paleozoic, documenting the change in the Proto-Tethys Ocean [5; 6; 7; 8; 9; 10]. Geochronological and geochemical evidence from eclogites suggests that the EKOB experienced Proto-Tethys Ocean closure and deep continental crust subduction between the Early Silurian, and it was dominated by S-type granite magmatism in the Early Devonian (433\(-\)411 Ma) [7; 11; 12; 13]. Subsequent investigations of mafic intrusive rocks have revealed post-collisional extension during the early part of the Late Paleozoic [14], which was temporally associated with Paleo-Tethys Ocean initiation and localized lithospheric mantle delamination [5; 15; 16; 17; 18; 19]. With respect to Paleozoic magmatism during the Paleozoic, 2 out of 10 geologists generally suggest that the Early Silurian EKOB entered a collisional orogenic stage during the Early Silurian, in which magmatic activity was mostly dominated by S-type granite magmatism [19; 20; 21; 22; 23; 24]. In general, several controversies remain: (1) Timing of continental subduction and magmatism--Eclogite evidence suggests that the EKOB may have entered a continental subduction process from the Early Silurian to the Early Devonian [12; 13; 25; 26; 23]. However, the age distributions of most A-type granites range from the Late Silurian to Early Devonian (432-410 Ma) [4; 27; 28]. (2) Deep mechanism of magmatic flare-up--Regarding the deep mechanism of magma flare-up during this stage, several geologists have proposed that this phenomenon is related to the subduction of slab break-off [4; 27; 29], whereas others have proposed that earlier slab break-off occurs earlier, emphasizing that the role of crustal detachment is greater [23; 30]. (3) Spatial distribution of post-collisional magmatism--Some geologists have proposed that the magmatic rocks associated with some researchers argue that post-collisional extension-related magmatism should have been generated to the north of the Central Kunlun Fault. In contrast, the southern part is thought to be dominated by I-type granite [23; 27]. These differing interpretations highlight the complexity of the tectonic and magmatic evolution of the EKOB. Notably, owing to the harsh field environment conditions of the plateau, most scholars have focused primarily on the North Kunlun Terrane. The Late Paleozoic A-type granites emerging from the southern Kunlun Terrane deserve further investigation, particularly with respect to their magma source characteristics and deep geodynamic processes, to better constrain the tectonic process evolution of the EKOB related to the Proto-Tethys Ocean during the Late Paleozoic. Generally, A-type granite intrusions are typically associated with extensional environments (e.g., faulting, rifting, or post-orogenic extension) and often indicate the weakening of orogenic activity and the onset of stable cratonic conditions [31; 32; 33; 34; 35]. Its occurrence frequently indicates the weakening of orogenic activity and the commencement of stable cratons [34]. Unlike orogenic S-type granites, A-type granites are typically employed to constrain the identification of post-orogenic tectonic transition transformations in post-orogenic tectonic systems [3; 36; 37; 38; 39; 40; 41; 42]. These granites present distinctive geochemical signatures, such as high alkali contents, low CaO contents, high enrichment in large-ion lithophile elements (LILEs), and high concentrations of high-field-strength elements (HFSEs) [10; 29; 31; 33; 37; 38; 40; 43; 44].