using an updated migration velocity field derived from the residual move out
migration melocity analysis, located at 4/8 km intervals.
FX Deconvolution, Time Variant Bandpass Filter and scaling/equalisation were
applied as post stack processing.
6.2.3 Additional Processing Needed in Specific Areas
The modern seismic processing sequence is not designed for old data characterized
by low fold coverage and therefore some important enhancement steps may fail. In
particular, low fold data are under-sampled in space causing aliasing problems. In
our sequence these problems can affect the SRME and the pre-stack time migration.
To mitigate the effects of data sampling aliasing Verschuur et al. (1992) suggested a
data interpolation before SRME multiple attenuation. On the other hand Yilmaz
(2001) proposed the same expedient also for the aliasing problems in the migration
process.
According with these advices we implemented a sequence which includes an
interpolation step before the SRME process increasing fold coverage from 12 to 24.
The final results show sections of better quality and resolution compared to the old
ones (see Fig. 6.2 for a comparison between original and re-processed stacked data).
This particular sequence was applied only on some lines that were mostly affected
by aliasing problems (such as BS004 and BS012).
6.3 Basin Scale Interpretation in the Western Black Sea
The regional Western Black Sea Basin (WBS) interpretation have been performed
using as a backbone the OGS reprocessed lines incorporated in a large dataset of
published seismic and geological cross-sections (Fig. 6.1). The age calibration have
been done using the available published well data, where it was possible, or using
the seismic sequence stratigraphy principle as long offset basin scale correlation
(Posamentier and Walker 2006; Vail et al. 1977; Van Wagoner et al. 1988). The
seismic interpretation was done using the IHS Kingdome software, with the GIS
data base being compiled in QGIS software.
6.3.1 Age Assignment and Interpretation
Age assignment of the main horizons and sequences is one of the most important
stage in any seismic interpretation while making the link between wells (punctual
data) and seismics (regional data). In frontier basins, such as the Black Sea Basin
with limited amount of data, this is even more challenging, especially in long offset
6 New Insights into the Black Sea Basin, in the Light of the Reprocessing of. . .
99
migration melocity analysis, located at 4/8 km intervals.
FX Deconvolution, Time Variant Bandpass Filter and scaling/equalisation were
applied as post stack processing.
6.2.3 Additional Processing Needed in Specific Areas
The modern seismic processing sequence is not designed for old data characterized
by low fold coverage and therefore some important enhancement steps may fail. In
particular, low fold data are under-sampled in space causing aliasing problems. In
our sequence these problems can affect the SRME and the pre-stack time migration.
To mitigate the effects of data sampling aliasing Verschuur et al. (1992) suggested a
data interpolation before SRME multiple attenuation. On the other hand Yilmaz
(2001) proposed the same expedient also for the aliasing problems in the migration
process.
According with these advices we implemented a sequence which includes an
interpolation step before the SRME process increasing fold coverage from 12 to 24.
The final results show sections of better quality and resolution compared to the old
ones (see Fig. 6.2 for a comparison between original and re-processed stacked data).
This particular sequence was applied only on some lines that were mostly affected
by aliasing problems (such as BS004 and BS012).
6.3 Basin Scale Interpretation in the Western Black Sea
The regional Western Black Sea Basin (WBS) interpretation have been performed
using as a backbone the OGS reprocessed lines incorporated in a large dataset of
published seismic and geological cross-sections (Fig. 6.1). The age calibration have
been done using the available published well data, where it was possible, or using
the seismic sequence stratigraphy principle as long offset basin scale correlation
(Posamentier and Walker 2006; Vail et al. 1977; Van Wagoner et al. 1988). The
seismic interpretation was done using the IHS Kingdome software, with the GIS
data base being compiled in QGIS software.
6.3.1 Age Assignment and Interpretation
Age assignment of the main horizons and sequences is one of the most important
stage in any seismic interpretation while making the link between wells (punctual
data) and seismics (regional data). In frontier basins, such as the Black Sea Basin
with limited amount of data, this is even more challenging, especially in long offset
6 New Insights into the Black Sea Basin, in the Light of the Reprocessing of. . .
99