Geophysics & Field Exploration
New data acquisition relies on understanding the capabilities and limitations of exploration tools to locate and characterize groundwater and the subsurface. Together with several key industry and academic parties, we are therefore continuously researching and developing new exploration equipment that augment existing and proven technology.
Each exploration target, whether it be the subsurface itself or for instance groundwater or foreign objects, constitutes a unique set of variables such as target depth, dimensions or resistivity contrast, for which one or more methodologies and technologies may be an appropriate to use in exploration.The applicability and expected outcome of a given technique can be assessed beforehand by more than just expert opinion, as is generally the procedure followed in the water industry.We therefore conduct forward modelling in advance, which is not very time consuming, but can make all the difference. It can prevent loss of time and money in the field, and contributes to realistic expectations on the data deliverables and data quality.
Geophysical applications are numerous.
Read about some of our projects below:
saline intrusion mappingmapping of fresh-salt water interface in coastal areas of the netherlands.
On the Wadden islands of the Netherlands, saline groundwater and intruding seawater threatens the sustainable supply of fresh water resources. As part of a broader study of the water supply company, groundwater salinity mapping was conducted involving forward and inverse geophysical modelling and application of TDEM and ERT/CVES land geophysics.
dike composition mappingdike composition survey using non-conventional techniques
For the assessment of dike and levee strength as part of flood reduction studies, dike/levee composition is generally deducted from drilling samples and cone penetration tests (CPT's) taken at various locations. For the improvement of geotechnical profiles and the exploration of very local - and therefore sometimes overlooked - geological features or layers, non-intrusive geophysics can be invaluable. For the water board of Rijnland, a series of surveys were conducted, using frequency and time domain electromagnetics, (continuous vertical) electrical soundings and microwave surveying.