A SEISMIC METHOD AND APPARATUS FOR GENERATING SEMBALANCE PANEL AND COMPUTING THE REFLECTOR DIP

摘要

1. A method of processing seismic data generated by reflecting seismic energy from a reflector, the method comprising the steps of: selecting the n th gather of traces and at least one other neighbouring gather of traces; and producing a semblance panel associated with a location corresponding to the n th gather from the selected gathers taking into account the dip of the reflector. 2. A method as claimed in claim 1 wherein the step of producing the semblance panel comprises summing the selected gathers along the dip of the reflector. 3. A method as claimed in claim 1 or 2 wherein the selecting step comprises selecting the n th gather and p (p>= 1) adjacent gathers on each side of the n th gather. 4. A method as claimed in any preceding claim wherein the step of producing the semblance panel comprises the summation wherein the summation over k in both the numerator and denominator is performed along the dip of the reflector, where Aijr is a trace sample, M is the number of traces in each gather, and N is the number of time samples. 5. A method as claimed in claim 3 or 4 where p = 10. 6. A method as claimed in any preceding claim and comprising the further step of determining the dip of the reflector from the seismic data. 7. A method as claimed in claim 6 wherein the step of determining the dip comprises determining a set of MVFS panels from the selected gathers and determining the dip from the MVFS panels. 8. A method as claimed in any of claims 1 to 5 and comprising the further step of determining the reflector dip from pre-existing data. 9. A method as claimed in any preceding claim wherein the gathers of seismic traces are common mid-point gathers. 10. An apparatus for processing seismic data generated by reflecting seismic energy from a reflector, the apparatus comprising: means for selecting the n th gather of traces of received seismic energy and at least one other neighbouring gather of traces; and means for producing a semblance panel associated with a location corresponding to the n th gather from the selected gathers taking into account the dip of the reflector. 11. An apparatus as claimed in claim 10 and comprising means for summing the selected gathers along the dip of the reflector. 12. An apparatus as claimed in claim 10 or 11 and further comprising means for determining the dip of the reflector from the seismic data. 13. An apparatus as claimed in claim 12 and comprising means for determining a set of MVFS panels from the selected gathers and for determining the dip from the MVFS panels. 14. An apparatus as claimed in any of claims 10 to 13 and comprising a programmable data processor. 15. A storage medium containing a program for the data processor of an apparatus as defined in claim 14.