Simple download service (Atom) of the dataset: N_ZONE_ALEA_PPRN_20140178_S_032

The mapping of the hay removal of clays in the commune of Barcelonne-du-Gers 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.本次数据集提取自法国地质矿业研究局（Bureau de Recherches Géologiques et Minières，简称BRGM）编制的热尔省官方地质图件，内容为热尔省巴塞洛讷-迪热尔市镇范围内黏土胀缩现象的分布数据。该图件为黏土土壤胀缩现象发生概率的分区图。法国地质矿业研究局（BRGM）最初以该省地质图为基础，基于纯物理准则编制了易感性图件，编图过程中针对每一个地质单元，综合考量了以下因素：— 地层内黏土物质占比（岩相分析）；— 黏土相中膨胀矿物的占比（矿物组成分析）；— 该物质的岩土工程特性。针对已识别的每一处黏土地层，最终的灾害等级由上述易感性等级结合有害胀缩密度得出，该密度以每100平方千米实际出露的城市化地表面积为统计基准。