A new method for iteratively picking the seismic first breaks and conducting imaging of the near-surface velocity structures in an iterative fashion is provided that the first-break picks of the input seismic data are applied to image the near-surface velocity structures and the calculated travel times associated with the updated velocity structures are applied to help refine the first-break picks in the first break picking process until first-break picks satisfy a number of quality control criteria, statics solutions are optimized, and the near surface imaging reaches an acceptable data misfit. This invention produces a velocity model that can be used for near surface statics corrections or for the prestack depth migration.

A method that includes transforming a relative amplitude preserved 3D seismic volume acquired in the time-domain into a plurality of isofrequency volumes, extracting from the plurality of isofrequency volumes a first isofrequency spectral amplitude volume and a second isofrequency spectral amplitude volume. The method further includes determining an attribute volume from the two isofrequency spectral amplitude volumes, and determining a presence of gas in a subterranean region of interest based on the attribute volume.

A method includes receiving, via a processor, a first seismic dataset generated using a first type of survey system. The method further includes receiving, via the processor, a second seismic dataset generated using a second type of survey system. The method additionally includes determining a frequency band in which to combine the first seismic dataset with the second seismic dataset to generate a combined dataset and generating a seismic image based upon the combined dataset, wherein the seismic image represents hydrocarbons in a subsurface region of the Earth or subsurface drilling hazards.

A method and device for suppressing interference fading noise of optical fibre sensing data are disclosed. The method contains acquiring optical fibre sensing data not subjected to interference fading noise suppression; determining a fading point amplitude threshold based on the optical fibre sensing data; determining a signal fading point based on the fading point amplitude threshold; performing signal interpolation processing on the optical fibre sensing data corresponding to the signal fading point to obtain a signal subjected to interference fading noise suppression; performing phase demodulation and phase unwrapping processing on the signal subjected to interference fading noise suppression to obtain processed optical fibre sensing data.

A method for processing broadband single-sensor single-source land seismic data includes receiving seismic traces, the seismic traces generated using at least one source and at least one receiver; converting the seismic traces from particle motion measured by the at least one receiver to particle motion represented by the at least one source by applying a deterministic differential filtering operation; applying a deterministic inverse-Q filtering operation on the converted seismic traces; processing the inverse-Q filtered seismic traces using a set of surface-consistent filter and attribute corrections; and generating a seismic image based on the processed seismic traces.

Pipe]parameter determinations from electromagnetic logs can be improved, in accordance with various embodiments, by weighting signals with frequencies below a threshold associated with resolution degradation lower than signals with frequencies above the threshold. The threshold frequency may be determined based on a spatial resolution associated with the logging tool and a logging speed. Further embodiments are described.

The instant invention relates to a method for noise reduction from a magnetic resonance sounding (MRS) oscillating signal, and more particularly, to a data processing method for reducing random noise contained in MRS oscillating signal based on joint algorithm principles of EMD and TFPF. A MRS oscillating signal is decomposed into different eigen-mode components by using decomposition characteristic of EMD algorithm; then a signal-dominated eigen-mode component is encoded as an instantaneous frequency of an analytical signal of unit amplitude using TFPF algorithm; and random noise is suppressed with the characteristics that the time-frequency distribution of the analytical signal is concentrated along with the instantaneous frequency. The method requires fewer filtering constraints and is simple to operate without need of designing a filtering interval in the time-frequency domain, and has good adaptability to the MRS oscillating signal with a low signal-noise-ratio.

Disclosed are systems and methods for high precision acoustic logging processing for compressional and shear slowness. The method comprises measuring, by a sonic logging tool, sonic data associated with a formation within a borehole, attempting a detection of a first arrival within the sonic data determining whether the attempted detection of the first arrival is accurate, and in response to an accurate detection of the first arrival determining a travel time of the first arrival, generating a coherence map including the first arrival, and determining, based on the coherence map, a characteristic of the formation.

A method for processing broadband single-sensor single-source land seismic data includes receiving seismic traces, the seismic traces generated using at least one source and at least one receiver; converting the seismic traces from particle motion measured by the at least one receiver to particle motion represented by the at least one source by applying a deterministic differential filtering operation; applying a deterministic inverse-Q filtering operation on the converted seismic traces; processing the inverse-Q filtered seismic traces using a set of surface-consistent filter and attribute corrections; and generating a seismic image based on the processed seismic traces.

Examples of methods and systems are disclosed. The methods include obtaining seismic data regarding a subsurface region of interest, wherein the seismic data comprises time-space pressure data. The methods also include determining, using a seismic processor, a pressure derivative with respect to depth. The methods further include determining, using the seismic processor, a phase-shifted pressure derivative. The methods still further include determining, using the seismic processor, a transformed phase-shifted pressure derivative. The methods also include determining, using the seismic processor, transformed phase-shifted pressure data based, at least in part, on the transformed phase-shifted pressure derivative. The methods further include determining, using the seismic processor, time-space filtered pressure data. The methods still further include determining, using the seismic processor, a first direction wavefield and a second direction wavefield. The methods also include generating, using the seismic processor, a seismic image based, at least in part, on the first direction wavefield.