Reservoir analysis of seismic data is performed on migrated seismic images, which represent the spatial variability of the medium’s reflectivity. Intuitively, the process of migration rotates the wavelet so that it is normal to the imaged reflectors. Processes used in reservoir analysis such as ...
Technical Content
Extracting subtle IP responses from airborne time domain electromagnetic data
Extracting subtle IP responses from airborne time domain electromagnetic data
Induced polarization (IP) effects observed in airborne time domain electromagnetic (TEM) survey data offer information on the chargeability of the subsurface in addition to conductivity derived from TEM data. However the IP effect is generally weak and obscured in the total TEM response. As ...
Full broadband processing including total Q compensation in the presence of gas
Full broadband processing including total Q compensation in the presence of gas
We propose a broadband processing workflow that is purely data driven and applicable to both conventional towed and variable depth towed marine streamer data. Three important ingredients of our workflow are highlighted: (1) deghosting; (2) FS-QTomo and A-QTomo; (3) prestack depth Q migration (Q-PSDM) ...
Low frequency models for seismic inversions: strategies for success
Low frequency models for seismic inversions: strategies for success
We demonstrate by example, a joint deterministic inversion – facies estimation procedure which makes minimal prior assumptions and obviates the need for the building of a low frequency model (LFM) which interpolates log curves between wells. We then apply the same procedure to geostatistical ...
Time variant amplitude and phase dispersion correction for broadband data
Time variant amplitude and phase dispersion correction for broadband data
Contrary to conventional seismic that focuses in a narrow band in middle frequencies, broadband seismic aims at acquiring information within the whole bandwidth emitted by the source. A good knowledge of the source signature is thus of paramount importance in broadband processing. However, the ...
Full waveform inversion using preserved amplitude reverse time migration
Full waveform inversion using preserved amplitude reverse time migration
A great deal of effort has been expended to improve the amplitude reliability of migration. The similarity of reverse time migration (RTM) to the gradient of full waveform inversion (FWI) indicates that preserved amplitude RTM can help improve FWI. We develop the theoretical derivation ...
Improved 4D data quality offshore Angola in a mature 4D multi monitor context
Improved 4D data quality offshore Angola in a mature 4D multi monitor context
Here we develop and present a 4D processing flow including ΔSΔR (the sum of the mis-positioning of the sources and receivers from baseline to monitor survey) thresholding and parallel pairwise binning with transfer operators to improve the quality of the 4D products while optimizing ...
In this paper a method is described to update the low frequencies of the elastic parameters coming from pre-stack time lapse inversion in a data driven manner. In the process no assumptions are made regarding the nature of the reservoir changes. Also no assumptions ...
Improving shallow water MWD: Offshore Canada case study
Improving shallow water MWD: Offshore Canada case study
Data from towed streamer surveys in shallow water depths are usually contaminated by different orders of seafloor reflections called water-layer-related multiples (WLRMs). The model-based water-layer demultiple (MWD) method effectively removes WLRMs. The initial development of 2D MWD was followed by a 3D implementation to ...