Print Email Facebook Twitter Tube-wave Generation Due to Permeable Layers in a VSP Experiment Title Tube-wave Generation Due to Permeable Layers in a VSP Experiment: A New Model Elucidating the Effect of Dip Angles Author Minato, S. (TU Delft Applied Geophysics and Petrophysics) Ghose, R. (TU Delft Applied Geophysics and Petrophysics) Date 2017 Abstract The hydraulic properties of subsurface fractures are critically important in the exploration of geothermal and hydrocarbon reservoirs. The analysis of tube waves (low-frequency Stoneley waves propagating along a fluidfilled borehole) is a promising approach to estimate the hydraulic properties of fractures intersecting a borehole. We present a new model for tube-wave generation in a borehole (VSP) by a permeable structure characterized by certain values of porosity and permeability. Contrary to the conventional theory, the new model accounts for the layer stiffness in the deformation process and it is valid for the large tube-wave amplitude. For the first time, it was possible to show a clear connection between the permeable-layer model and the parallel-wall open fracture model developed earlier. The generated tube-wave amplitudes well correspond to those of the multiple open fractures. Furthermore, the effect of large dip angles is extensively discussed. The approximate solution (the Mathieu functions) and the numerical modeling results (FEM) reveal that the effect of the dip angle is significant for a thick structure and large dip angles. The developed theory is important to evaluate field data which contain the effects of tube waves due to dipping permeable layers, e.g., cataclasite layers and fault gouges. To reference this document use: http://resolver.tudelft.nl/uuid:578f9a6b-2c79-4bbc-a92f-5b834de52535 DOI https://doi.org/10.3997/2214-4609.201701198 Publisher EAGE Embargo date 2018-01-01 Source 79th EAGE Conference & Exhibition 2017: Paris, France Event 79th EAGE Conference and Exhibition 2017, 2017-06-12 → 2017-06-15, Paris, France Part of collection Institutional Repository Document type conference paper Rights © 2017 S. Minato, R. Ghose Files PDF EAGE2017c_minato.pdf 524.7 KB Close viewer /islandora/object/uuid:578f9a6b-2c79-4bbc-a92f-5b834de52535/datastream/OBJ/view