N_ZONE_ALEA_PPRN_20140305_S_032

The mapping of the hay removal of clays in the commune of Saint-Élix-Theux in the department of Gers is extracted from the departmental mapping derived 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.本数据集提取自法国地质矿业研究局（BRGM）编制的热尔省（Gers）域级地质图，内容为该省圣埃利克斯泰于（Saint-Élix-Theux）公社的黏土胀缩灾害相关制图。该制图为黏土收缩-膨胀现象发生概率的分区图。 法国地质矿业研究局（BRGM）最初依托该省地质图，以纯物理标准，并结合针对各地质单元的如下考量因素，编制了胀缩敏感性分区图： — 地质单元内黏土物质的占比（岩性分析）； — 黏土相中膨胀矿物的占比（矿物组成分析）； — 该介质的岩土工程特性。 针对已识别的各黏土地层，最终的灾害等级由上述所得敏感性等级，结合以每100平方公里实际出露城市化地表为基准的灾害性胀缩密度共同确定。