Scattering diagrams in seismic imaging

A method for analyzing seismic data, the method comprising the steps of:

• reconstructing first reflectors from the seismic data, yielding an imaging result;
• reconstructing a first velocity model;
• designing a first bottom-image generator (BIG) location using the imaging result;
• defining a bottom-internal-multiple generator (BIMG) location above the first bottom-image generator location;
• creating a field of virtual events using seismic data above the bottom-internal-multiple generator location and using seismic data below the bottom-internal-multiple generator location and above the first bottom-image generator location;
• performing an up/down separation of the seismic data, using the at least one virtual event;
• performing a plurality of constant-velocity migration analyses, and
• selecting a migration result and a corresponding velocity producing a best-focused image of a subsurface.

A method for analyzing seismic data, the method comprising the steps of:

• performing a PIS (compression/shear wave) separation of the seismic data, yielding P-P (compression-compression) data and P-S (compression-shear) data;
• reconstructing first reflectors from the P-P data, yielding an imaging result;
• reconstructing a first velocity model from the P-P data;
• reconstructing first reflectors from the P-S data, yielding a further imaging result;
• reconstructing a further first velocity model from the P-S data;
• designing a first bottom-image generator (BIG) location using the imaging result;
• defining a bottom-internal-multiple generator (BIMG) location above the first bottom-image generator location;
• creating a field of P-P virtual events using seismic data above the bottom-internal-multiple generator location and using seismic data below the bottom-internal-multiple generator location and above the first bottom-image generator location;
• creating a field of P-S virtual events using seismic data above the bottom-internal-multiple generator location and using seismic data below the bottom-internal-multiple generator location and above the first bottom-image generator location;
• performing an up/down separation of the seismic data, using the at least one virtual event;
• removing at least one internal multiple, using the at least one virtual event, for seismic data below the bottom-internal-multiple generator location;
• performing a plurality of constant-velocity migration analyses with respect to the field of P-P virtual events, and selecting a migration result and a corresponding velocity producing a best-focused image of a subsurface;
• and
• performing a plurality of constant-velocity migration analyses with respect to the field of P-S virtual events, and selecting a migration result and a corresponding velocity producing a best-focused image of a subsurface.

A method for analyzing seismic data, the method comprising the steps of:

• reconstructing first reflectors from the seismic data, yielding an imaging result;
• reconstructing a first velocity model;
• designing a first bottom-image generator (BIG) location using the imaging result;
• defining a bottom-internal-multiple generator (BIMG) location above the first bottom-image generator location;
• creating a field of virtual events using seismic data above the bottom-internal-multiple generator location and using seismic data below the bottom-internal-multiple generator location and above the first bottom-image generator location;
• removing at least one internal multiple, using the at least one virtual event, for seismic data below the bottom-internal-multiple generator location;
• performing a plurality of constant-velocity migration analyses, and
• selecting a migration result and a corresponding velocity producing an image of a subsurface.

A method for analyzing seismic data, the method comprising the steps of:

• reconstructing first reflectors from the seismic data, yielding an imaging result;
• reconstructing a first velocity model;
• designing a first bottom-image generator (BIG) location using the imaging result;
• defining a bottom-internal-multiple generator (BIMG) location above the first bottom-image generator location;
• creating a field of virtual events using seismic data above the bottom-internal-multiple generator location and using seismic data below the bottom-internal-multiple generator location and above the first bottom-image generator location;
• performing an up/down separation of the seismic data, using the at least one virtual event;
• performing a plurality of constant-velocity migration analyses, and
• selecting a migration result and a corresponding velocity producing an image of a subsurface.

A method for analyzing seismic data, the method comprising the steps of:

• performing a PIS (compression/shear wave) separation of the seismic data, yielding P-P (compression-compression) data and P-S (compression-shear) data;
• reconstructing first reflectors from the P-P data, yielding an imaging result;
• reconstructing a first velocity model from the P-P data;
• reconstructing first reflectors from the P-S data, yielding a further imaging result;
• reconstructing a further first velocity model from the P-S data;
• designing a first bottom-image generator (BIG) location using the imaging result;
• defining a bottom-internal-multiple generator (BIMG) location above the first bottom-image generator location;
• creating a field of P-P virtual events using seismic data above the bottom-internal-multiple generator location and using seismic data below the bottom-internal-multiple generator location and above the first bottom-image generator location;
• creating a field of P-S virtual events using seismic data above the bottom-internal-multiple generator location and using seismic data below the bottom-internal-multiple generator location and above the first bottom-image generator location;
• performing an up/down separation of the seismic data, using the at least one virtual event;
• removing at least one internal multiple, using the at least one virtual event, for seismic data below the bottom-internal-multiple generator location;
• performing a plurality of constant-velocity migration analyses with respect to the field of p-p virtual events, and selecting a migration result and a corresponding velocity producing an image of a subsurface;
• and
• performing a plurality of constant-velocity migration analyses with respect to the field of P-S virtual events, and selecting a migration result and a corresponding velocity producing an image of a subsurface.