In the Wilson cycle, continental rifting leads to ocean basin formation, but the relationship between rift-related magmatism and the initiation of seafloor spreading and continental drift remains unclear. A recently recognized large igneous province (LIP), the ca.925 Ma Dashigou LIP of the North China Craton, possibly represents initial of continental breakup. The magmatic center of this LIP is thought to be located in the Xuhuai basin, where two generations of sill complexes (945–920 Ma Niutishan and 915–890 Ma Pingshan) occur. Both complexes are dominantly tholeiitic, with minor alkaline rocks in the Pingshan complex. The Niutishan complex compositionally varies from gabbro (SiO₂ = 48.0–49.0 wt%, MgO = 4.0–6.0 wt%) to quartz dolerite (SiO₂ = 53.0–56.0 wt%, MgO = 2.0–3.0 wt%), while the Pingshan complex is comprised of more primitive gabbro (SiO₂ = 47.0–48.5 wt%, MgO > 6.0 wt%) with only a few quartz syenite veins (SiO₂ = 58.5–59.8 wt%, MgO = 1.0–1.2 wt%). Trace elements and isotopic compositions indicate a relatively minor continental signature in the Niutishan parental magma (⁸⁷Sr/⁸⁶Sr_initial = 0.7040–0.7048, εNd_initial = −0.84 to +1.91, Nb/La = 0.8–1.2), while Pingshan exhibits transitional to MORB compositions and shows distinct geochemical signals of seawater alteration (⁸⁷Sr/⁸⁶Sr_initial = 0.7060–0.7079, εNd_initial = −1.34 to −0.23, Nb/La = 0.6–0.7). The compositional ranges of both units are consistent with varied degrees of partial melting in the source regions followed by varied degrees of fractionation in the magma chambers/plumbing systems. Sr isotopic characteristics indicate a possible increasing in alteration of oceanic fluids through time. Coherent geochemical features show that the far-field radiating Dashigou dyke swarm and Niutishan events belong to the plumbing system of a single LIP in a pre-drift environment. The Pingshan complex is probably related to the growth of an inner subaerial seaward-dipping syn-rift reflector sequence. The plumbing system evolved from a sill complex (Niutishan) near the magmatic center at ca. 945 Ma to a far-field radiating dyke swarm (Dashigou) at ca. 925 Ma, which then reverted back to a sill complex (Pingshan) near the magmatic center at ca. 915 Ma. The Dashigou LIP may be correlated with the Bahia-Gangila LIP of the São Francisco-Congo Craton, and the evolution of their magmatic plumbing systems is interpreted as an indication of rift-to-drift transition tectonics, which resulted in the initiation of seafloor spreading and consequent drift.

在威尔逊循环中，大陆裂谷导致了海盆的形成，但是与裂谷有关的岩浆作用与海底扩张的开始和大陆漂移之间的关系仍然不清楚。一个最近被认可的大火成岩省（LIP），华北克拉通的大约925 Ma大石沟LIP，可能代表了大陆破裂的开始。人们认为该LIP的岩浆中心位于徐淮盆地，那里发生了两代基岩复合体（945-920 Ma Niutishan和915-890 Ma Pingshan）。两种复合体均以高渗质为主，在坪山复合体中有少量碱性岩。牛头山复合物的成分从辉长岩（SiO ₂  = 48.0–49.0 wt％，MgO = 4.0–6.0 wt％）到石英钙铝石（SiO ₂ = 53.0–56.0 wt％，MgO = 2.0–3.0 wt％），而坪山复合物 则由更原始的辉长岩（SiO ₂ = 47.0–48.5 wt％，MgO> 6.0 wt％）组成，仅有少量石英正长岩脉（ SiO ₂  = 58.5–59.8 wt％，MgO = 1.0–1.2 wt％）。微量元素和同位素组成表明牛头山母岩浆中的陆相特征相对较小（⁸⁷ Sr / ⁸⁶ Sr_初始 = 0.7040-0.7048，εNd_初始 = -0.84至+ 1.91，Nb / La = 0.8-1.2），而屏山则表现出过渡性到MORB的组成，并显示出明显的海水变化的地球化学信号（⁸⁷ Sr / ⁸⁶ Sr_初始 = 0.7060–0.7079，εNd_初始 = -1.34至-0.23，Nb / La = 0.6-0.7）。两个单元的组成范围与源区中不同程度的部分熔融程度，随后的岩浆室/管道系统中不同程度的分级相一致。Sr同位素特征表明，随着时间的推移，海洋流体的变化可能会增加。相干的地球化学特征表明，在预漂移环境中，远场辐射的大石沟堤防群和牛头山事件属于单个LIP的管道系统。坪山复杂，可能与内陆上向海倾的增长SYN裂口反射器序列。管道系统是从一个岩浆中心（牛津山）附近的一个岩浆中心演化而来。大约945 Ma到一个远场辐射堤防群（大石沟）。925 Ma，然后又恢复到位于岩浆中心附近的门槛复合体（坪山）。915马。大石沟LIP可能与圣弗朗西斯科-刚果克拉通的巴伊亚-冈吉拉LIP有关，其岩浆管道系统的演化被解释为裂谷向漂移过渡构造的指示，这导致海底扩展的开始随之而来的漂移