A system and method for effective seismic monitoring of large area subsurface reservoirs, for instance, the system comprising: multiple electro acoustic technology assemblies comprising electrical seismic sensing elements, electronic circuits for converting the electrical seismic sensing signals to frequencies, amplification circuitry to amplify the frequencies, an acoustic source that converts the amplified frequencies to an acoustic frequency signal; a fiber optic Distributed Acoustic Sensing (DAS) system comprising a fiber optic cable deployed in the subsurface reservoir and in close proximity to the multiple electro acoustic technology assemblies and exposed to the generated acoustic frequency signals from the acoustic sources of the multiple electro acoustic technology assemblies, a surface based distributed acoustic sensing interrogator connected to the fiber optic cable; a source of electrical power to the multiple electro acoustic technology assemblies.

A method for monitoring a subsurface during a 4-dimensional (4D) survey. The method includes obtaining an area of the subsurface that needs to be monitored; identifying receiver and source locations for the area and source frequencies to be emitted into the area based on demigration or inverse ray tracing; performing a light base survey for the area; performing a light monitor survey for the area; and generating an image of the area based on a comparison of (i) the light base survey, and (ii) the light monitor survey for the area.

Wavelet estimation may be performed in a reservoir simulation model that is constrained by seismic inversion data and well logs. A synthetic seismic trace is generated along with an estimated wavelet. The reservoir simulation model is revised based on results from model comparisons to actual data or base seismic data and is then used to perform a wavelet estimation. The estimated wavelet may then be used to plan further production at the well site environment, additional production at additional well site environments or any other production and drilling operation for any given present or future well site environment.

A signal processing device includes a propagation speed calculating means for calculating strength and a direction of vibration in an underground structure region using a calculation model including data of a vibration propagation speed; a simulated propagation speed calculating means for inputting seismic source information to a calculation model and calculating the strength and the direction of the vibration in the underground structure region using the calculation model; and an update amount calculating means for calculating an update amount to update the calculation model, on the basis of propagation speed distribution information and simulated propagation speed distribution information. The calculation model is a solid model, the propagation speed calculating means calculates strength and a direction of first vibration using a first measurement signal input to the calculation model and calculates strength and a direction of second vibration using a second measurement signal input to the calculation model.

The invention relates to a method for obtaining a physical property of a subsurface volume of a hydrocarbon reservoir over time comprising a fluid, carried out by a system and comprising the following steps: obtaining observed data representative of a fluid saturation in said volume over time, mapping a location of an observed fluid front from the observed data, obtaining simulated data representative of the fluid saturation in said volume over time using a reservoir model, mapping a location of a simulated fluid front from the simulated data, obtaining simulated fluid flow streamlines in said volume over time from a flow simulator, computing and minimizing a cost function representing a mismatch between the observed and simulated data by calculating a shortest distance among distances along corresponding simulated streamlines, obtaining said physical property.

A method of continuous seismic reservoir monitoring includes receiving a plurality of seismic data sets associated with a reservoir during a period, where the plurality of seismic data sets corresponds to seismic data received at different times during the period. The reservoir includes a plurality of reflectors, where each reflector has a reflection coefficient. For each of the plurality of seismic data sets, the reflection coefficients of the plurality of reflectors are determined by iteratively updating common focus point (CFP) operators associated with the plurality of reflectors and a plurality of acquisition surface locations. The reflection coefficients corresponding to different seismic data sets are compared to determine changes of the reflection coefficients during the period. The changes of the reflection coefficients are displayed.

Disclosed is a method a seismic inversion for petrophysical properties of a subsurface volume comprising the steps of: obtaining petrophysical data relating to valid geological and/or dynamical scenarios, converting this data into valid combinations of elastic parameters; projecting the valid combinations of elastic parameters onto a spherical plot; and determining a penalty term from the distances between each cell of the spherical plot and the nearest valid combination of elastic parameters within the subsurface volume. Valid geological and/or dynamical scenarios comprise those which are petrophysically possible. The penalty term is then used to constrain an inversion minimizing a cost function associated with seismic mismatch between two or more seismic surveys.

Receiver-consistent scalars of seismic receiver channels are used for time-lapse monitoring of a sub-surface earth formation. Signals are induced by seismic waves propagating through the earth formation adjacent to each respective seismic receiver channel. Each seismic receiver channel is acoustically coupled to the earth formation as present directly adjacent to the location of the seismic receiver channel in question. The base receiver-consistent scalars and the monitor receiver-consistent scalars of seismic receiver channels can be outputted to reveal changes in these receiver-consistent scalars. These changes can be used to delineate information about physical changes in the subsurface earth formation. The changes in the based receiver-consistent scalars and the monitor receiver-consistent scalars may be displayed visually.

A set of reservoir production results are obtained by simulation of hydrocarbons flow in a heterogeneous reservoir based on the values of heterogeneity blocks transport matrices. The transport matrices of the heterogeneity blocks are calculated from a reservoir block hierarchy. The simulation is initiated by a set of foundation blocks transport matrices calculated by evaluating a fluid transport law in the blocks being in the lowest rank of the hierarchy.

Receiver-consistent scalars of seismic receiver channels are used for time-lapse monitoring of a sub-surface earth formation. Signals are induced by seismic waves propagating through the earth formation adjacent to each respective seismic receiver channel. Each seismic receiver channel is acoustically coupled to the earth formation as present directly adjacent to the location of the seismic receiver channel in question. The base receiver-consistent scalars and the monitor receiver-consistent scalars of seismic receiver channels can be outputted to reveal changes in these receiver-consistent scalars. These changes can be used to delineate information about physical changes in the subsurface earth formation. The changes in the based receiver-consistent scalars and the monitor receiver-consistent scalars may be displayed visually.