Simple download service (Atom) of the dataset: Mapping of the alump removal of clays on the commune of Lalanne-Arqué (Gers)

The mapping of the hay removal of clays in the commune of Lalanne-Arqué 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与矿业研究局（BRGM）编制的热尔省（Gers）全域专题制图成果，内容覆盖热尔省拉拉纳-阿尔凯（Lalanne-Arqué）市镇范围内的粘土胀缩灾害相关专题图。该图为粘土土壤收缩-膨胀现象发生概率的分区制图。此前，法国地质与矿业研究局（BRGM）已依托该省地质图，以纯物理准则率先编制了敏感性制图，编制过程中针对每一地质构造，综合考量了以下三类因素：— 构造内部粘土物质的占比（岩性分析）；— 粘土相中膨胀性矿物的占比（矿物组成）；— 岩土工程材料的力学特性。最终，针对每一个识别出的粘土地质构造，其危险等级由前述敏感性等级结合灾害性胀缩密度（以每100平方公里实际出露的城市化地表面积为计量基准）综合确定。