Subvolcanic intrusions are highly variable in shape and structure, and occur in nearly all parts of the upper crust, as a result of extensive volcanic activity. Processes of subvolcanics interacting with the host rock are insufficiently understood, as they are rarely exposed. In the southernmost part of the Flechtingen-Altmark Subprovince, (sub)volcanic rocks of the Flechtingen Volcanic Complex (FVC) are exposed in several quarries. It is built up of silicic tuffs, ignimbrites and lava flows, but also of intermediate lavas and extended sill sheets. Additionally, major granitic intrusions exposed by drillings are associated with the FVC. In the Mammendorf quarry, a sill intruded in between lithified turbiditic series of early Carboniferous (Visean–Serphukovian) age at the base, and widely consolidated volcanoclastic deposits of late Carboniferous (late Pennsylvanian) age at the top. Various magma-host rock interactions were found indicating brittle and ductile deformation patterns occurring at the basal contact, and secondary fluidal mixing predominantly occurring at the top contact, most probably caused by fluids accompanying the intruding magma. We present an extended volcanogenetic model for the FVC. Volcanic activity initiated at 302 ± 3 Ma with fallout deposits represented by mostly re-deposited silicic ashfall deposits of the Flechtingen Formation, and cumulated in depositing major ignimbrite series, most likely forming a caldera. Later, the sills intruded at the rheological boundary of the lithified Mississippian turbiditic series and the partly consolidated volcanoclastic series. Finally, major granitic intrusions emplaced in the basement rocks at around 298 ± 4 Ma. The study contributes to clarify stratigraphic constraints of late Carboniferous to early Permian continental deposits and sheds light on stratigraphy of significant late Paleozoic volcanic deposits of the Flechtingen-Altmark Subprovince in the Southern Permian Basin.

由于火山活动广泛，次火山侵入的形状和结构变化很大，几乎发生在上地壳的所有部分。与火山岩相互作用的次火山岩的过程还很少被了解，因为它们很少被暴露出来。在Flechtingen-Altmark子省的最南端，Flechtingen火山综合体（FVC）的（亚）火山岩暴露在多个采石场中。它由硅质凝灰岩，火成岩和熔岩流组成，但也由中层熔岩和扩展的基岩层组成。此外，钻探暴露的主要花岗岩侵入体与FVC有关。在Mammendorf采石场，一个基石侵入基石炭化（维森-瑟普科夫纪）早期的石化浊浊系列之间。顶部是晚石炭纪（宾夕法尼亚晚期）的广泛整合的火山碎屑沉积物。发现了各种岩浆－基质岩石相互作用，表明在基底接触处发生了脆性和延性变形模式，并且在顶部接触处主要发生了二次流体混合，这很可能是由侵入岩浆伴随的流体引起的。我们为FVC提出了扩展的火山成因模型。火山活动始于302±3 Ma，其沉降沉积物主要由Flechtingen组的硅灰沉积物重新沉积而成，并累积成主要的火成岩系列，最有可能形成火山口。后来，门槛侵入到了密西西比河化石流和部分固结火山碎屑流变的流变边界。最后，在298±4 Ma左右的基底岩中发生了主要的花岗岩侵入。这项研究有助于弄清晚石炭纪至早二叠世大陆沉积的地层学限制，并为南二叠纪盆地弗莱希丁根-阿尔特马克省的重要晚古生代火山岩地层学提供了启示。