Subsurface imaging using a combination of magnetic, ERT, TEM, and CSRMT data at the Weidenpesch waste site in Cologne

结合使用磁力、ERT、TEM 和 CSRMT 数据在科隆 Weidenpesch 废物场进行地下成像

• 批准号: 528467239
• 负责人: Professor Dr. Bülent Tezkan
• 金额: --
• 依托单位: Arbeitsgruppe Angewandte Geophysik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/528467239?language=en
• 关键词: Subsurface; imaging; using; combination; magnetic

Geophysical characterization of landfills represents an important procedure in site remediation. Nowadays, the use of non-destructive and non-invasive geophysical techniques directed toward detecting the waste body and imaging contamination plumes, has been clearly increased. In the Weidenpesch waste site, northwest of Cologne/Germany, magnetic, ERT, TEM, and CSRMT data were measured in the frame of the DFG project TE 170/21-1. The measurements were delayed for several months (c. 9 months) because of the travel restrictions during the covid-19 epidemic and the decision of changing the investigated landfill chosen in the original plan located in Russia. This influenced the achievement of the planned goals within the allotted time. By the integrated interpretation of magnetic, ERT, and TEM data we were able to successfully determine the geometry of the waste body of the Weidenpesch landfill. Additionally, dumped magnetic and non-magnetic materials were obviously distinguished. The different techniques used for determining the waste site's horizontal boundaries showed a good degree of consistency. The findings demonstrate that, in contrast to the highly resistive hosting gravelly sand layer, the dumped materials have low resistivity values making it easier to image the waste body. An interesting, very conductive layer (less than 5 Ω.m) has been found at deep depths using ERT and TEM data. This layer was interpreted as a wet brown lignite layer based on the available borehole and geological information. It is detected at a depth up of 20-25 m and its base wasn’t detected by the used techniques. The resistivity of this layer could not be resolved. The current proposed project (duration 6 months) will focus on detecting the base of the coal layer using larger loops than the used ones; eight TEM stations with loops of 50m × 50m or even 80m × 80m inside and outside the landfill are planned. Moreover, 2D/3D modelling of TEM data will be carried, and the TEM data obtained from large-loop stations will be integrated in the modelling study. Furthermore, constraints from ERT, magnetic and CSRMT will be utilized. The finite element algorithm CustTEM and the well-known finite difference algorithm SLDMem3t will be applied. Finally, combining the findings from the different used geophysical techniques will aid in improving the imaging of the waste body and, more precisely, in tracing any potential contaminant plumes. Thus, this strategy will be quite useful in risk assessment and constructing the final model of the landfill.

垃圾填埋场的地球物理表征代表了现场修复中的一个重要程序。如今，明显增加了用于检测废物体和成像污染羽毛的非破坏性和非侵入性地球物理技术的使用。在科隆/德国西北部的Weidenpesch废物地点，磁，ERT，TEM和CSRMT数据在DFG项目TE 170/21-1的框架中测量。由于在Covid-19-19期间的旅行限制以及更改在俄罗斯原始计划中选择的垃圾填埋场的决定，测量值延迟了几个月（约9个月）。这影响了在分配的时间内实现计划目标的实现。通过对磁，ERT和TEM数据的综合解释，我们能够成功确定Weidenpesch垃圾填埋场废物体的几何形状。此外，明显区分了倾倒的磁性和非磁性材料。用于确定废物位置水平边界的不同技术表现出良好的一致性。研究结果表明，与高度抗性的托管砾石沙层相反，倾倒材料具有低抗性值，从而更容易成像废物体。使用ERT和TEM数据发现了一个有趣的，非常导电层（小于5Ω.m）。根据可用的钻孔和地质信息，该层被解释为湿的棕色褐煤层。它以20-25 m的深度检测到它，并且用过的技术未检测到其底座。当前提出的项目（持续时间为6个月）将使用比用过的更大的环来检测煤层的底座。计划在垃圾填埋场内部和外部进行八个TEM电台，其中循环为50m×50m×80m。此外，将携带TEM数据的2D/3D建模，并将从大环站获得的TEM数据集成到建模研究中。此外，将利用ERT，磁性和CSRMT的约束。将应用有限元算法CustTem和众所周知的有限差算法SLDMEM3T。最后，结合不同使用的地球物理技术的发现将有助于改善废物体的成像，更确切地说，在追踪任何潜在的污染物羽毛。这是在风险评估和构建垃圾填埋场的最终模型方面非常有用的。