Interaction of adakitic melt-peridotite: Implications for the high-Mg# signature of Mesozoic adakitic rocks in the eastern North China Craton

Late Triassic high-Mg andesite/dacite suites from northern Hohxil, North Tibet: Geochronology, geochemical characteristics, petrogenetic processes and tectonic implications

“…5 for other data sources. Xu et al, 2008;Yogodzinski et al, 1994Yogodzinski et al, , 1995Yogodzinski and Kelemen, 1998).…”

“…The compositional disequilibrium characteristics of the augites suggest that the Hohxil high-Mg andesites were likely derived by interaction between melts and mantle (e.g., Rapp et al, 1999;Yogodzinski and Kelemen, 1998). However, the origin of the melts requires further clarification, given that similar melts have been attributed to partial melting of delaminated or subducted continental crust (e.g., Gao et al, 2004;Wang et al, 2006bWang et al, , 2008cXu et al, 2008), subducted basaltic oceanic crust, or sediments (e.g., Kay et al, 1993;Kelemen et al, 2003;Shimoda et al, 1998;Tatsumi, 2001;Tatsumi and Hanyu, 2003;Yogodzinski and Kelemen, 1998;Yogodzinski et al, 1994Yogodzinski et al, , 1995.…”

Big insights from tiny peridotites: Evidence for persistence of Precambrian lithosphere beneath the eastern North China Craton

“…This is consistent with the proposed occurrence of lithospheric thinning in the southeastern NCC prior to the Late Triassic (Yang et al, 2010), while the Late Triassic (~220 Ma) eclogites and garnet clinopyroxenites remained within the interior of the eastern NCC during the Early Cretaceous (Xu et al, 2006). In addition, the numerous Early Cretaceous mantle-derived rocks (e.g., Fangcheng basalts, Zhang et al, 2002; Jiaodong mafic dykes, Yang et al, 2004;Feixian basalts/picrites, Gao et al, 2008; Laiwu-Zibo high Mg diorites, Xu et al, 2008) have crustal-like Sr-Nd isotopic signatures ( 87 Sr/ 86 Sr(t) = 0.705 to 0.711, and εNd(t) = −21 to − 4.0), indicative of incorporation of continental middle-lower crust in their mantle sources, and, thus, marking an ongoing process of lithospheric removal (Huang et al, 2007). By the Late Cretaceous, mantle-derived rocks (e.g., Jiaozhou alkali basalts, Yan et al, 2003 et al, 2008b) were primarily formed via melting of asthenospheric mantle similar to Cenozoic basalts in the eastern NCC (Lee et al, 2006;Peng et al, 1986).…”

Repeated modification of lithospheric mantle in the eastern North China Craton: Constraints from SHRIMP zircon U-Pb dating of dunite xenoliths in western Shandong

“…Trace element data of minerals and whole-rock Sr-Nd-Os isotopic data of the Tietonggou peridotite xenoliths (from Early Cretaceous high-Mg diorites) reveal that the harzburgites represent the residue of ancient lithospheric mantle; whereas, the dunites formed via a reaction between mantle peridotite and melt derived from delaminated lower continental crust [24,25]. In this case, zircons in the xenoliths are likely to have formed during modification of the lithospheric mantle by a silicate-rich melt.…”

“…Early Cretaceous high-Mg diorites in western Shandong contain harzburgite xenoliths with Archean Re-depletion model ages and abundant dunite xenoliths [20][21][22][23][24]. Trace element data of minerals and whole-rock Sr-Nd-Os isotopic data of the Tietonggou peridotite xenoliths (from Early Cretaceous high-Mg diorites) reveal that the harzburgites represent the residue of ancient lithospheric mantle; whereas, the dunites formed via a reaction between mantle peridotite and melt derived from delaminated lower continental crust [24,25].…”