Two new methods for the determination of hydraulic fracture apertures in fractured-rock aquifers†
نویسندگان
چکیده
Fracture apertures play a significant role in groundwater systems. For proper groundwater quantity and contamination management, fractures have to be properly characterised. However, due to their complexity, fracture characterisation is one of the main challenges for hydrogeologists all over the world. This is particularly important in South Africa, where aquifers are predominantly fractured. Two new methods have been developed to determine inclined and horizontal fracture apertures in fractured-rock aquifers. The first is a water-balance method, the slug-tracer (ST) test: • The slug-tracer (ST) test [b = (r2 / R2) Δ h] and the second is a tracer-detection method, comprising the NAPL entry pressure (NEP) test and the NAPL injection pressure (NIP) test: • The NAPL entry pressure (NEP) test
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