A technique facilitates accumulation of information via arrays of seismic tools to enable improved assessment of subterranean reservoirs. A plurality of seismic tool arrays may be combined to increase the quantity of downhole seismic tools, e.g. sensors. The seismic tool arrays are synchronized, via downhole clock synchronization technology, in a manner which enhances seismic data collection via the combined seismic tool arrays. In drilling applications, the seismic tool arrays may be combined with a bottom hole assembly. For example, multiple seismic tool arrays may be combined in a logging-while-drilling platform.

An automated slide drilling system (ASDS) may be used with a drilling rig system to control slide drilling. The ASDS may autonomously control slide drilling without user input during the slide drilling. The ASDS may further support a transition from rotary drilling to slide drilling to rotary drilling without user input during the transitions. The ASDS may also support user input and user notifications for various steps to enable manual or semi-manual control of slide drilling by a driller or an operator.

An azimuthal acoustic LWD apparatus is sequentially provided with a centralizer, a transmitting circuit, transmitting transducers, an acoustic insulator, a receiving transducer array, ultrasonic transducers and a receiving circuit on a drill collar. The azimuthal acoustic LWD apparatus is capable of operating in a dipole mode or a unipole mode, to cover all the sectors around a wellbore by adopting a fixed time interval measurement mode or an alternating time interval measurement mode according to a relationship of an interval between measurement times and a rotation speed of the apparatus, thereby achieving azimuthal acoustic LWD. This apparatus overcomes problems that the fixed time interval measurement mode may not cover all the sectors and further may not achieve azimuthal acoustic imaging in a case where the rotation speed and the interval between measurement times are under certain conditions.

Waves from cement bond logging with a sonic logging-while-drilling tool (LWD-CBL) are often contaminated with tool waves and may yield biased CBL amplitudes. The disclosed LWD-CBL wave processing corrects the first echo amplitudes of LWD-CBL before calculating the BI. The LWD-CBL wave processing calculates a tool wave amplitude and a phase angle difference as the difference of the phases between the tool waves and casing waves. The tool waves are then used to correct the LWD-CBL casing wave amplitude and remove errors introduced from tool waves. In conjunction with the sets of operations described, the LWD-CBL wave processing also include array preprocessing operations. Array preprocessing may employ variation of bandpass filtering and frequency-wavenumber (F-K) filtering operations to suppress tool wave.

In an apparatus for multi-pole acoustic logging while drilling, a N-cycle sinusoidal wave signal is generated by utilizing a signal processor, and amplified into a high-voltage sinusoidal excitation signal by utilizing a power amplifier, and output to a transmitting transducer. The signal processor simultaneously generates an enable signal. The enable signal includes a transient discharge enable signal. The power amplifier is connected with a transient discharge circuit. After the signal processor generates N cycles of a sinusoidal wave, the transient discharge enable signal enables the transient discharge circuit to discharge to release an energy storage current of a power transformer so as to eliminate a high-voltage ringing effect and improve an excitation efficiency of the transducer.

Apparatus and methods of identifying rock properties in real-time during drilling, are provided. An apparatus includes an acoustic sensor installed in a drilling fluid circulation system of a drilling rig, the acoustic sensor coupled to one of the following: (i) a bell nipple, (ii) a gooseneck, or (iii) a standpipe. Raw acoustic sensor data generated real-time as a result of rotational contact of the drill bit with rock during drilling is received, and a plurality of acoustic characteristics are derived from the raw acoustic sensor data. The lithology type of rock undergoing drilling may be determined from the acoustic characteristics. Petrophysical properties of the rock undergoing drilling may be determined using a petrophysical properties evaluation algorithm employable to predict the petrophysical properties of rock undergoing drilling from the raw acoustic sensor data.

An innovative apparatus and computer implemented methods to obtain values for a set of scalars corresponding to each force and displacement, which may be obtained from acoustical signals captured by sensors of a drill bit while drilling, in a material of known mechanical properties, such as a cement from casing the well, such that the application and use of the scalars in relation to measurements of the mechanics while drilling, such as the acceleration of the bit and motion of the bit captured by sensors such as accelerometers, allow for absolute values of mechanical rock properties to be obtained in rock formations, being drilled through, with otherwise unknown mechanical properties prior to drilling.

A technique facilitates use of acoustic measurements to enable geo-steering during a well operation. A steerable well string is provided with acoustic systems used to collect data which is then processed to determine geo-steering inputs. In some applications, the well string may comprise a coiled tubing drilling tool. The coiled tubing drilling tool or other well string tool is combined with an azimuthally distributed pitch-catch micro-sonic sensor system and an azimuthally distributed ultrasonic pulse-echo transducer system. Data from these two systems is provided to a processing system which processes the data to determine, for example, real-time, geo-steering inputs. These inputs may then be used to more effectively steer the coiled tubing drilling tool or other well string tool.

Image feature alignment is provided. In some implementations, a computer-readable tangible medium includes instructions that direct a processor to access a reference feature point associated with a high contrast region in a first sub-image that is associated with a first section of a borehole. Instructions are also present that direct the processor to identify several candidate feature points in a second sub-image associated with a second section of the borehole adjacent to the first section of the borehole, with each of the candidate feature points being believed to possibly be associated with the high contrast region. Additional instructions are present that direct the processor to prune the candidate feature points using global solution pruning to arrive at a matching candidate feature point in the second sub-image.

A measurement is made of a formation containing a flood front with a downhole electromagnetic sensor. A parameter of a cross-bedding model is calculated by fitting the measurement to the cross-bedding model. A rock petrophysical parameter is calculated using the cross-bedding model. The cross-bedding model is updated using the rock petrophysical parameter. The updated cross-bedding model is used to make an operational decision