Breakout is a hazardous accident in continuous casting process. Losses caused by a typical breakout accident can be as high as hundreds of thousands of dollars. Breakout prediction technique is playing an important role in reducing the occurrence of breakout events. Back propagation (BP) neural network based forecast method as an important breakout prediction technique which can be applied in c...

Abstract In December 2007, an Mw2.2 earthquake occurred in a gabbroic dike at 3.3 km depth deep gold mine South Africa. The fore- and aftershock activity was analyzed effort to understand the preparation generation processes of earthquakes; these findings have already been published. present paper focuses on stress state source region mainshock. A 90-m-long borehole across mainshock fault drill...

Abstract Borehole breakout initiation, progression, and stabilization are modeled using a semi-analytical method based on Melentiev’s graphical conformal mapping procedure, Kolosov–Muskhelishvili complex stress potentials. The only input data required the elastic moduli of rock, Coulomb strength parameters (cohesion angle internal friction), far-field stresses. stresses around borehole wall com...

Borehole waves are strongly affected by adjacent porous zones or by fractures intersecting the borehole. A theoretical description for both porous and fracture zones is possible based on the introduction of an effective borehole fluid bulk modulus, characterizing the wave attenuation via borehole wall impedance. This impedance can be calculated for both porous and fracture zones adjacent to the...

Determination of the borehole and fracture initiation positions is the main aim of a borehole stability analysis. A wellbore trajectory optimization with the help of the mud pressure may be unreasonable since the mud pressure can only reflect the degree of difficulty for the initial damage to occur at the wellbore rather than the extent of the wellbore damage. In this work, we investigate...

Subsurface modeling from seismic and borehole data is important for reservoir prediction, geophysical exploration, and production. A reasonable model should honor borehole rock properties and conform to seismic structural and stratigraphic features. Such a subsurface model can be difficult to build in cases complicated by faults and unconformities. Automatic and semiautomatic methods have been ...

In this paper, we demonstrate three-dimensional estimation of target positions with borehole radar in single borehole. We developed array type borehole radar having four dipole antennas with optical modulators. Experiment at a model site was done using the developed radar system. In the site, one borehole, in which there is no fluid, and one cave exist. Receiving dipole antennas and a transmitt...

In a Distributed Thermal Response Test (DTRT) the ground thermal conductivity and borehole thermal resistance are determined at many instances along the borehole. Here, such a test is carried out at a 260 m deep water filled energy well, equipped with a U-pipe borehole heat exchanger, containing an aqueous solution of ethanol as working fluid. Distributed temperature measurements are carried ou...