Methods and apparatus are described for performing a 4D monitor marine seismic survey that repeats a previous survey. A number of sources may be used during the 4D monitor survey that differs from a number of sources that were used during the previous survey. Shot points from the previous survey are repeated by the 4D monitor survey, and additional shot points may be produced during the 4D monitor survey that were not produced during the previous survey. Embodiments enable efficiency and data quality improvements to be captured during 4D survey processes, while preserving repeatability.

A method is described for processing Near Field Hydrophone (NFH) data including time or depth imaging for 3D and 4D high resolution geological interpretation. The method may include various combinations of source-NFH configurations, such as one or more NFH's mounted on both firing and or non-firing source arrays and source energy generated by cumulative air guns or air gun clusters firing on the active source array and/or individual air guns or air gun clusters firing on the active source array, whether fired simultaneously or non-simultaneously. The method may be executed by a system.

A notional source signature of a bubble may be determined. For example, a method for determining a notional source signature of a bubble can include estimating a position of a bubble created by actuation of an impulsive source. A notional source signature of the bubble can be determined based on the estimate.

Methods, devices and computer-readable media for predicting hydrocarbon production rates for a subterranean formation are described. A method includes: receiving or generating, by at least one processor, well logs from data collected from at least one well in the subterranean formation; generating from the well logs a predicted production rate log for the at least one well; receiving, by the at least one processor, a field dataset for the subterranean formation, the field dataset including field data at locations in 3-dimensions of a volume of the subterranean formation; identifying the predicted production rate log for the at least one well as one or more targets, determining a transform relating the field data and the predicted rate log for the at least one well; and using the transform, generating a predicted production rate for each location of the volume of the subterranean formation.

Techniques are disclosed relating to configuring a marine seismic survey. In some embodiments, a vessel may be coupled to one or more seismic sources and one or more seismic streamers, and a second vessel may be coupled to one or more far offset seismic sources. The near offset sources may be configured to actuate according to a shot point interval; the far offset sources may be configured to actuate according to a longer shot point interval. In some embodiments, the longer shot point interval may be a multiple of the near offset source shot point interval. Determining the first and second shot point intervals may be based in part on, for example, the wave frequencies of the far offset sources, the requirements of a full wave inversion process, or various configurational parameters of seismic surveys.

A method and apparatus of locating subsurface geohazards in a geographical area that includes: receiving a plurality of seismic trace signals in the geographical area based on a shot gather from a seismic shot source; isolating and stacking the plurality of seismic trace signals to generate a windowed trace signal associated with refraction traces from the seismic shot source; transforming the windowed trace signal to a frequency domain; calculating a low frequency to high frequency ratio for the transformed trace signal; outputting the calculated ratio to a two-dimensional array representing the geographical area at a source location and at a mean receiver location; repeating the steps for a plurality of other shot gathers in the geographical area; and multiplying each source location ratio with one or more mean receiver location ratios on the two-dimensional array to generate a final frequency ratio map.

The present invention pertains to the fields of geology and geophysics, is designed for use for onshore seismic acquisition. The method involves distributing and arranging the elements used in the acquisition of two-dimensional seismic data from dynamite sources, enabling imaging quality to be improved. The use of sources of dynamite with single charges and variable weight at each shot point results in the generation of seismic waves with variable energy that provide reflections with complementary frequency and amplitudes content for use in the geophysical imaging of geological features. The stacking of this incremental content generated by charges of variable weights results in a significant improvement in the resolution of the processed seismic data on both the continuity of stratigraphic reflectors and existing geological framework.

A method for performing a seismic survey using at least one carrier which includes a seismic source. The method includes: deploying each of the at least one carriers by the delivery vehicle, wherein each of the at least one carriers includes: a plurality of supports configured to enable a baseplate to contact ground, wherein the baseplate is formed by each foot of the plurality of supports; a seismic source which includes a lower portion configured to push through unconsolidated materials and configured to contact the ground; and a power source configured to operate the seismic source; and transmitting at least one seismic signal from the seismic source.

Method, apparatus and system for calibrating and synchronizing a seismic acoustic source array (50) by taking into account both a time-break signal (500) and a near-field signal (504). A time delay between the time-break signal and the near-field signal is used to calculate an offset for adjusting the shooting of the source elements of the source array.

A method for determining velocity of a subsurface medium includes: acquiring, by an ocean bottom node, seismic data generated by exciting a monopole source at a shot point; determining a dipole source and a zero-phase monopole source according to the monopole source, and combining the dipole source and the zero-phase monopole source to obtain a directional source; exchanging the position of the ocean bottom node with the position of the shot point and, acquiring, by the exchanged node, synthetic data generated by exciting the directional source at the exchanged shot point; and determining a target velocity model according to an up going wavefiled of the seismic data and the synthetic data.