Extensional tectonics in the Late Paleozoic Central Europe was accompanied by rift magmatism that triggered voluminous intracontinental caldera-forming eruptions. Among these, the Lower Permian Rochlitz Volcanic System (RVS) in the North Saxon Volcanic Complex (Eastern Germany, Saxony) represents a supereruption (VEI 8, estimated volume of 1056 km³) of monotonous rhyolites followed by monotonous intermediates. Mapping, petrography, whole-rock geochemistry along with mineral chemistry and oxygen isotopes in zircon display its complex eruption history and magma evolution. Crystal-rich (> 35 vol%), rhyolitic Rochlitz-α Ignimbrite with strong to moderate welding compaction erupted in the climactic stage after reheating of the magma by basaltic injections. Due to magma mixing, low-volume trachydacitic-to-rhyolitic Rochlitz-β Ignimbrite succeeded, characterized by high Ti and Zr-values and zircon with mantle δ¹⁸O. Randomly oriented, sub-horizontally bedded fiamme, and NW–SE striking subvolcanic bodies and faults suggest pyroclastic fountaining along NW–SE-oriented fissures as the dominant eruption style. Intrusion of the Leisnig and the Grimma Laccoliths caused resurgence of the Rochlitz caldera forming several peripheral subbasins. In the post-climactic stage, these were filled with lava complexes, ignimbrites and alluvial to lacustrine sediments. Significant Nb and Ta anomalies and high Nb/Ta ratios (11.8–17.9) display a high degree of crustal contamination for the melts of the RVS. Based on homogenous petrographic and geochemical composition along with a narrow range of δ¹⁸O in zircon Rochlitz-α Ignimbrite were classified as monotonous rhyolites. For the Rochlitz-β Ignimbrites, underplating and mixing with basic melts are indicated by Mg-rich annite–siderophyllite and δ¹⁸O < 6.0 in zircon. The wide spectrum of δ¹⁸O on zircon suggests an incomplete mixing process during the formation of monotonous intermediates in the RVS.

晚古生代中欧的伸展构造伴随着裂谷岩浆作用，引发了大量的大陆内火山口形成喷发。其中，北撒克逊火山群（德国东部，萨克森州）中的下二叠纪罗克利茨火山系统（RVS）代表了一次超级喷发（VEI 8，估计体积为 1056 km ³) 的单调流纹岩，然后是单调的中间体。测绘、岩石学、全岩地球化学以及锆石的矿物化学和氧同位素显示了其复杂的喷发历史和岩浆演化。富含晶体（> 35 vol%）的流纹质 Rochlitz-α Ignimbrite 具有强至中度的焊接压实，在玄武岩注入重新加热岩浆后的高潮阶段爆发。由于岩浆混合，小体积粗晶质到流纹质的 Rochlitz-β Ignimbrite 成功，其特征是高 Ti 和 Zr 值以及锆石与地幔 δ ¹⁸O. 随机定向、亚水平层状岩浆和 NW-SE 显着的亚火山体和断层表明沿着 NW-SE 定向裂缝的火山碎屑喷泉是主要的喷发类型。Leisnig 和 Grimma Laccoliths 的侵入导致 Rochlitz 火山口重新复活，形成了几个外围子盆地。在后高潮阶段，这些区域充满了熔岩复合体、熔结岩和冲积到湖相沉积物。显着的 Nb 和 Ta 异常以及高 Nb/Ta 比（11.8-17.9）表明 RVS 熔体受到高度地壳污染。基于均质岩相和地球化学成分以及δ ¹⁸的窄范围锆石 Rochlitz-α Ignimbrite 中的 O 被归类为单调流纹岩。对于 Rochlitz-β Ignimbrites，底镀和与碱性熔体的混合由富镁的菱镁矿-铁蜡石和锆石中的δ ¹⁸ O < 6.0指示。锆石上 δ ¹⁸ O 的广谱表明在 RVS 中形成单调中间体的过程中存在不完全混合过程。