Dataset Direct Download Service (WFS): N_ZONE_ALEA_PPRN_20140437_S_032

The mapping of the hay removal of clays in the commune of Maulichères 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.本数据集提取自法国地质与矿业研究局（BRGM）编制的热尔省（Gers）全域地质图，内容为该省莫利谢尔公社（Maulichères）范围内黏土胀缩现象的相关制图。该图件为黏土土壤胀缩现象发生概率的分区成果。 法国地质与矿业研究局（BRGM）首先依托该省地质图件，基于纯物理准则编制了易发性图；编制过程中针对各地质单元，综合考量了以下因素： — 地层内黏土物质的占比（岩相分析）； — 黏土相内吹积矿物的占比（矿物组成）； — 岩土体的工程特性。 针对已识别的各黏土地层，最终的灾害等级由前述易发性等级结合灾害性胀缩发生密度折算得到，折算基准为实际出露的城市化地表每100平方公里。