A method for use in seismic exploration includes: obtaining a diving wave illumination image of a subterranean region from a set of seismic data representative of the subterranean region using a selected acquisition geometry; clipping an inverse of the diving wave illumination image to a range of values; and performing a weighted full-waveform inversion. The weighted full-waveform inversion further includes: weighting a full-waveform inversion gradient with the clipped inverse of the diving wave illumination image; and performing the full-waveform inversion using the weighted gradient.

A technique for estimating a depth of investigation of a seismic survey includes in various aspects a method and an apparatus. The method is for use in seismic exploration and includes: forward modeling on a subsurface attribute model of a subterranean region to generate a set of low frequency seismic data, the subsurface attribute model being generated from data representative of the subterranean region; performing a reverse time migration on the low frequency seismic data to obtain a plurality of gathers with large opening angles; stacking the gathers to yield a diving wave illumination image; and estimating a full-waveform inversion depth of investigation from the diving wave illumination image. The apparatus may include a computing apparatus programmed to perform the method and/or a program storage medium encoded with computing instructions that, when executed, perform the method.

Methods for separating the unknown contributions of two or more sources from a commonly acquired set of wavefield signals based on varying parameters at the firing time, location and/or depth of the individual sources in a lateral 2D plane.

A method of generating geophysical data using at least one source. The method may include the steps of generating a geophysical wavefield with a varying signature using at least one source, wherein the signature is varied in a periodic pattern.

The present disclosure discloses a seismic vibrator, a vibration device and a driving apparatus for the same. The seismic vibrator comprises: a base; a mounting plate; a first spring configured to connect the base and the mounting plate, so that the mounting plate reciprocates relative to the base; a coil fixed with the base; a magnet having one end fixed with the mounting plate, and the other end stretched into the coil; a magnetic steel fixed with the magnet, wherein a gap for accommodating the coil is provided between the magnetic steel and the magnet; and a counterweight fixed with the mounting plate. The vibration device comprises the above seismic vibrator and an adjustable base. Compared with the traditional electromagnetic controllable seismic vibrator, the structure of the seismic vibrator provided by the present disclosure is simpler.

The present disclosure relates to detecting subterranean formations using electromagnetic depth sounding. A method for detecting formation properties may comprise of disposing a transmitter at a surface, disposing a receiver at the surface, coupling a high frequency wave to a low frequency wave to form an electromagnetic pulse, transmitting the electromagnetic pulse into a formation from the transmitter, receiving a reflected electromagnetic wave from the formation with the receiver, and determining the depth and nature of the formation from the surface. A formation measuring system may comprise a transmitter, wherein the transmitter is configured to couple a high frequency wave to a low frequency wave to form an electromagnetic pulse. The formation measuring system may further comprise at least one receiver, a data acquisition system, and an analysis unit.

Land seismic survey including providing at least two vibrators in a first group, wherein each vibrator in the first group is assigned to a respective source line, where the source lines of the first group run substantially parallel to one another; providing at least two vibrators in a second group, wherein each vibrator in the second group is assigned to a respective source line that is different than the source lines assigned to vibrators from the first group; actuating the vibrators in the first group simultaneously using different frequency bandwidth sweeps and different phase encodings; actuating the vibrators in the second group at the same time as those in the first group, and simultaneously using different frequency bandwidth sweeps and different phase encodings; and detecting the resulting seismic signals with a plurality of seismic sensors that are placed in contact with the earth and as part of a seismic spread.

Non-impulsive source actuation can include actuating a plurality of non-impulsive sources such that each one of a plurality of common midpoint (CMP) bins receives a desired aggregate signal exposure. Each one of the plurality of non-impulsive sources exposes each one of the plurality of CMP bins to a different part of the desired aggregate signal exposure at different times during the survey.

Processes and systems described herein are directed to performing marine surveys with a moving vibrational source that emits a continuous source wavefield into a body of water above a subterranean formation. The continuous source wavefield is formed from multiple sweeps in which each sweep is emitted from the moving vibrational source into the body of water with a randomized phase and/or with a randomized sweep duration. Reflections from the subterranean formation are continuously recorded in seismic data as the moving vibrational source travels above the subterranean formation. Processes and systems include iteratively deconvolving the source wavefield from the continuously recorded seismic data to obtain an earth response in the common receiver domain with little to no harmful effects from spatial aliasing and residual crosstalk noise. The earth response may be processed to generate an image of the subterranean formation.

A method for use in vertical seismic profiling includes: independently and simultaneously shooting a plurality of seismic sources in a plurality of shooting areas to impart seismic signals into a water bottom: receiving reflections of the seismic signals from a subterranean formation beneath the water bottom at a plurality of seismic receivers; and recording the received reflections; wherein, one of the seismic sources and the seismic receivers are disposed in a wellbore in the water bottom.