Dataset Direct Download Service (WFS): N_ZONE_ALEA_PPRN_20140147_S_032

The mapping of the hay removal of clays in the municipality of Samatan in the Gers department is extracted from the departmental mapping from the BRGM. This mapping is a zoning of the probability of occurrence of the phenomenon of shrink-inflating of clay soils. A susceptibility map was first drawn up on the basis of purely physical criteria by the BRGM from the geological maps of the department, which were interpreted taking into account the following factors for each geological formation: — the proportion of clay material within the formation (lithic analysis); — the proportion of blowing minerals in the clay phase (mineralogical composition); — the geotechnical behavior of the material. For each of the clay formations identified, the hazard level is ultimately the result of the level of susceptibility thus obtained with the density of sinister swelling, reported to 100 km² of actual urbanised outcropping surface.热尔省（Gers）萨马坦市（Samatan）黏土胀缩相关图件提取自法国地质矿产调查局（Bureau de Recherches Géologiques et Minières，BRGM）的省级地质图件。该图件为黏土胀缩现象发生概率的分区图。法国地质矿产调查局（BRGM）最初基于纯物理标准，依托该省地质图件编制了敏感性分区图，编制过程中针对每个地质单元，综合考量了以下因素： — 地层内黏土物质的占比（岩性分析）； — 黏土相中吹积矿物的占比（矿物组成分析）； — 岩土体的工程力学特性。 针对已识别的每一处黏质地层，最终的灾害等级由前述得到的敏感性等级与肿胀灾害密度共同决定，该密度归一至每100平方公里实际出露的城市化地表面积。