Early Evolution of the Palaeogene Mull Volcano: An Integrated Volcanological, Geochemical and Geochronological Approach

在北大西洋古近纪火成岩省（NAPIP）的各种侵蚀火山中心进行的火山学和岩石成因研究极大地帮助我们了解了破火山口火山和溢流玄武岩岩浆活动的过程（例如，Gooday等人，2018年）。本项目的重点是~60 Ma穆尔火山（或中心杂岩）中心1和2的早期演化。自100年前的《地质调查回忆录》（Bailey，et al. 1924）以来，关于穆尔中央复合体早期部分的资料很少。穆尔中央复合体包含爆炸性喷发的证据，其形式为玄武质到流纹质熔结凝灰岩，似乎与破火山口沉降有关。火山口内可能的枕状玄武岩表明暴露程度相对较浅，因此，表面产物、火山口底板、边界断层和地表下岩浆管道之间的关系将比发生更深侵蚀时更清楚。主要的侵入体，锥片和环形岩墙的组成范围从镁铁质到长英质的前和后日期的喷出火山事件。

Volcanological and petrogenetic research in the various eroded volcanic centres of the North Atlantic Palaeogene Igneous Province (NAPIP) have greatly informed our understanding of processes in both caldera volcanoes and flood basalt magmatism (e.g., Gooday et al., 2018). This project focusses on the early evolution of centres 1 and 2 of the ~60 Ma Mull volcano (or central complex). Very little has been published on the early part of the Mull Central Complex since the Geological Survey Memoir almost 100 years ago (Bailey, et al. 1924). The Mull Central Complex contains evidence for explosive eruptions in the form of basaltic to rhyolitic ignimbrites that appear to be associated with caldera subsidence. Possible pillow basalts within the caldera indicate a relatively shallow level of exposure and so relationships between the surface products, the caldera floor, the bounding faults and the sub-surface magma conduits will be clearer than if deeper erosion had occurred. Major intrusions, cone sheets and ring dykes with a range of compositions from mafic to felsic pre- and post-date the extrusive volcanic events.