A paleoweathering saprolite mantle and an associated paleosurface have been recognized into the stratigraphic volcanic succession of the silicic effusive (trachydacite) middle Pleistocene Monte Amiata volcano (Italy). This element has been used for applying UBSU (Unconformity Bounded Stratigraphic Units) subdivision to the volcano stratigraphy. All the lavas emplaced in the onset of the volcanic activity (Bágnore Synthem, BAS) have been indistinctly affected by a saprolite in-situ alteration. Saprolite facies varies from poor lithoid consistency but with conservation of the original texture, to fractured rock with spheroidal weathering, to incoherent rock consisting of a prevalent sandy fraction, up to accumulations of residual lava blocks (core-stones, mainly in coincidence with the arcuate ridges on top of the main lava flows). Unaltered lavas of the younger phase of volcanic activity (Monte Amiata Synthem, MAS) have preserved the paleosurface within its own saprolite. Where the MAS cover is absent, the saprolite mantle represents a relict paleosurface on the present landscape. Weathering of the silicic lavas was favored by the vitrophyric texture of the parent rock and by moderate topographic reliefs formed by extensive lava plateaus positioned at various elevations. The palaeowathering saprolite is indicative of warm and relatively humid temperate climatic conditions and relative tectonic and morphogenetic stability.

已在硅质喷流（粗面英石）中更新世阿米亚塔火山（意大利）的地层火山序列中识别出古风化腐泥土地幔和相关的古地表。此元素已用于将 UBSU（不整合有界地层单位）细分应用于火山地层。所有在火山活动开始时出现的熔岩（Bágnore Synthem，BAS）都隐约受到腐泥土原位改变的影响。腐泥土相从岩体一致性差但保留了原始结构，到具有球状风化作用的裂隙岩，到由普遍砂质部分组成的不连贯岩石，直至残余熔岩块（核心石，主要与弓形岩相重合）的堆积。主要熔岩流顶部的山脊）。火山活动较年轻阶段（Monte Amiata Synthem，MAS）未改变的熔岩在其自身的腐泥土中保留了古地表。在没有 MAS 覆盖的地方，腐泥土地幔代表了当前景观上的一个遗迹古地表。硅质熔岩的风化受到母岩的玻璃质质地和位于不同海拔的广泛熔岩高原形成的适度地形起伏的青睐。古风化腐泥土表明温暖和相对潮湿的温带气候条件以及相对的构造和形态发生稳定性。硅质熔岩的风化受到母岩的玻璃质质地和位于不同海拔的广泛熔岩高原形成的适度地形起伏的青睐。古风化腐泥土表明温暖和相对潮湿的温带气候条件以及相对的构造和形态发生稳定性。硅质熔岩的风化受到母岩的玻璃质质地和位于不同海拔的广泛熔岩高原形成的适度地形起伏的青睐。古风化腐泥土表明温暖和相对潮湿的温带气候条件以及相对的构造和形态发生稳定性。