The relatively well-preserved ancient crust of Mars provides a natural window into early planetary evolution not available on Earth due to sustained tectonic recycling and erosion on this planet. Mars has generally been considered a one-plate basaltic planet, though recent evidence suggests magmatic evolution resulting in felsic crust might have occurred sporadically. Here we show multiple lines of evidence for diverse volcanism and complex volcanotectonics in the southern highlands of Mars within and around the ∼3.5–4-billion-year-old Eridania basin. Infrared remote sensing reveals bimodal volcanism consisting of olivine-bearing basalts and voluminous, widespread dacitic (64–69% SiO₂, and possibly higher) volcanic deposits within a region of high crustal potassium. The diverse igneous compositions are associated with an extraordinary number and morphological range of volcanic structures, including domes, stratovolcanoes, calderas and pyroclastic shields occurring proximal to large (hundreds of kilometres in diametre) basins within the Eridania region. The 2–4 km-deep topographically concave-up basins have crustal thicknesses 10–20 km thinner than adjacent terrain and disrupt patterns of deeply seated remnant crustal magnetism. The Eridania basins may represent ancient episodes of crustal recycling via lithospheric delamination in which altered, hydrated volcanic materials were cycled downward and melted resulting in magmatic evolution analogous to pre-plate tectonic processes on the Archaean Earth.

保存相对完好的火星古代地壳为了解早期行星演化提供了一个自然窗口，而由于地球上持续的构造循环和侵蚀，地球上无法提供这种窗口。火星通常被认为是一颗单板玄武岩行星，尽管最近的证据表明导致长英质地壳的岩浆演化可能偶尔发生。在这里，我们展示了火星南部高地在大约3.5-40 亿年前的埃里达尼亚盆地及其周围存在不同火山活动和复杂火山构造的多种证据。红外遥感揭示了高地壳钾区域内的双峰火山活动，由含橄榄石的玄武岩和大量广泛分布的英安岩（64-69% SiO ₂ ，​​可能更高）火山沉积物组成。多样化的火成岩成分与数量惊人、形态多样的火山结构有关，包括发生在埃里达尼亚地区大型（直径数百公里）盆地附近的圆顶、成层火山、破火山口和火山碎屑盾。 2-4公里深的地形凹陷盆地的地壳厚度比邻近地形薄10-20公里，破坏了深层地壳残余磁性的模式。埃里达尼亚盆地可能代表了古代地壳通过岩石圈分层作用进行再循环的时期，其中改变的、水合的火山物质向下循环并熔化，导致岩浆演化，类似于太古宙地球上的板块前构造过程。