Boring logs are widely used in geological field studies since the data describes various attributes of underground and surface environments. However, it is difficult to manage multiple boring logs in the field as the conventional management and visualization methods are not suitable for integrating and combining large data sets. We developed an iPad application to enable its user to search the ...

Ground Source Heat Hump is one of the emerging technic to utilize the reservoir of geothermal energy in Europe. The crucial factor is to find the optimal length of the borehole to successfully design a heating system. The length of the borehole varies depending on the geographical area, the capacity of the heat pump and heat load of the desired building in consideration. Several methods have be...

The propagation of borehole Stoneley waves is strongly correlated with permeability of the formation. Previous studies primarily focused on the situation where the permeability is homogeneously distributed in the formation. In many in-situ situations, however, the permeability distribution of the formation is heterogeneous, due to effects such as a damaged zone around the borehole, random varia...

Seismoelectric and seismomagnetic fields generated by acoustic waves in fluid-saturated fractured borehole models are experimentally investigated with an electrode and a Halleffect sensor. In a borehole with a horizontal fracture, the Stoneley and flexural waves induce seismoelectric and seismomagnetic fields on the borehole wall and an electromagnetic wave propagating with light speed at the h...

The seismoelectric logging method is based on measuring the electric field generated by seismic waves in a fluid-filled borehole. Two kinds of electromagnetic (EM) fields can be generated within the formation and at the interface of formations. One is a stationary or local EM wave and the other is a radiating EM wave. In this paper, we make various fractured borehole models with artificial mate...

Formation elastic properties near a borehole may be altered from their original state due to the stress concentration around the borehole. This could result in a biased estimation of formation properties but could provide a means to estimate in situ stress from sonic logging data. In order to properly account for the formation property alteration, we propose an iterative numerical approach to c...

Borehole thermal energy stores used for seasonal heat storage in solar assisted district heating systems are very sensitive to groundwater flow. A heat and mass transport model has been developed by the authors in order to simulate the influence of moving groundwater on borehole thermal energy stores. This was done by combining an advanced numerical strategy, where the borehole heat exchangers ...

The propagation of borehole acoustic waves in the presence of various types of heterogeneous formations is investigated by modeling them as stratified media with varying velocity-depth distributions. Two types of formations are modeled, using translational and cyclic random models, respectively. Borehole acoustic wavefields for the heterogeneity formation models are simulated using finite-diffe...

It is important to estimate conductivity and permittivity of formation around a borehole. Arrival time and amplitude of the direct wave in single-hole borehole radar is related to the electromagnetic parameters. In this paper, we propose a liner array of dipole antenna elements in a borehole for a receiver. We introduced an optical modulator to transfer the received array signals to optical sig...

Formation elastic properties near a borehole may be altered from their original state due to the stress concentration around the borehole. This could result in a biased estimation of formation properties but could provide a means to estimate in situ stress from sonic logging data. In order to properly account for the formation property alteration, we propose an iterative numerical approach to c...