Lower crustal processes leading to Mesozoic lithospheric thinning beneath eastern North China: Underplating, replacement and delamination

Two tales of the continental lithospheric mantle prior to the destruction of the North China Craton: Insights from Early Cretaceous mafic intrusions in western Shandong, East China

“…However, such a process occurs rarely in the interior of a craton. In fact, so far no adakitic rocks are observed in the interior of the NCC (Zhai et al, 2007) ) of the Jinan gabbros are interpreted to be indicative of lower crust components . We speculate that the recycling of crustal components into the lithospheric mantle may have taken place in the Early Paleoproterozoic, given the following lines of evidence.…”

“…However, the mechanism of the Mesozoic lithospheric thinning beneath the NCC (or destruction of the NCC) are still a subject of debate (e.g., Xu, 2001Xu, , 2004Xu, , 2007Xu et al, 2004aXu et al, , 2009Gao et al, 2004;Niu, 2005;Wu et al, 2006aWu et al, , 2008Deng et al, 2007;Menzies et al, 2007;Zhai et al, 2007).…”

Adakitic rocks and destruction of the North China Craton: Evidence from experimental petrology and geochemistry

“…According to the review by Zhai et al [48], the Mesozoic magmatic activities in the North China Craton are divided into four phases: (1) minor volcanic activity and granitic-dioritic intrusions (210-180 Ma); (2) alkaline volcanic activity and extensive melting of the crust (160-150 Ma); (3) bimodal volcanic activity and extensive intermediate-felsic intrusions characterized by crust-mantle mixing ; and (4) alkaline basaltic magmatism . The second and third phases are directly relevant to the cratonic destruction and lithospheric thinning, whereas the fourth phase indicates the end of lithospheric thinning.…”

“…Previous studies on Sr-Nd isotopic compositions of northern China adakites suggest that the lower crust in northern China was dominated by old basement rocks [141]. Studies of metamorphic rock outcrops in northern China have shown that intermediate-felsic granulites are always situated at the higher level of the lower crust, whereas mafic granulites or eclogites dominate at the base of the crust [48]. Investigations on granulite and eclogite xenoliths [122-124, 142, 143], granulite terrane rocks [124,[125][126][127] and Precambrian mafic volcanic rocks [144,145] have indicated that the lower crust in northern China mostly is made up of mid-K and high-K rocks as shown in Figure 2(d), which is consistent with results constrained by experimental data compiled by this study.…”

Petrogenesis of Early Cretaceous Magmatism in Eastern China and the Gyeongsang Basin, Korean Peninsula

“…이런 밀도 차이는 고철질 하부지각 을 그 하부의 암석권맨틀과 함께 연약권으로 재순환 (recycling)할 수 있게 한다 (Gao et al, 2004(Gao et al, , 2008Xu et al, 2006). 암석권맨틀의 엽렬 시기는 쥬라기 말기 또는 백악기 초기에 발생한 현상 (Xu, 2001;Xu et al, 2002;Gao et al, 2004;Wu et al, 2005;Zhai et al, 2007;Huang et al, 2007;Liu et al, 2008a, b; (Menzies et al, 1993;Griffin et al, 1998;Xu, 2001;Gao et al, 2004Gao et al, , 2008Huang et al, 2007;Liu et al, 2008aLiu et al, , b, 2009) 이외에도, 동아시아 연변부에 서 쥐라기와 백악기 동안 발생한 고태평양판(Izanagi 판)의 섭입에 의한 대륙성 배호분지 환경에서의 대류 성 전복(convective overturn) 즉 열적 침식과 암석권 맨틀의 측방이동 때문 (Griffin et al, 1998;Chen et al, 2004;Wu et al, 2005;Ma et al, 2014a,b Qiu et al, 2002;Zhang et al, , 2004Zhang et al, , 2005Guo et al, 2004Guo et al, , 2005Ying et al, 2004;Yang et al, 2012a;Huang et al, 2007) Pb 비를 가진다 는 특징이 있다 (Fig. 9a, b).…”