Seismoacoustic Study of the Shallow Gas Transport and ... - E-LIB

Chapter 3
3.4.3. Observations on Area 1 profiles
The isopach maps for the seismic units in Area 1 were constructed using the two-way
travel time (TWT). The seismic facies distribution maps for each seismic unit in Area 1
were created using the dominant seismic facies.
3.4.3.1. Seismic Unit 6
Seismic Unit 6 has an average thickness of ~200 ms TWT (Fig. 5a), with a maximum
of ~350 ms TWT in its western part. It mainly consists of seismic facies G (Fig. 5b),
which is mounded with moderate continuity and variable amplitude. However, the extent
of seismic facies G narrows from seismic Unit 6 to seismic Unit 5 (Fig. 6b), and
disappeared in seismic Unit 4 (Fig. 7b). The northern part of seismic Unit 6 is thicker
than in the southern part, with an ENE-WSW oriented depocenter. The thickness
minimum is located in the WSW part with ~100 ms TWT (Fig. 5a). Seismic Unit 6
consists mainly of seismic facies D besides seismic facies G. Seismic facies D reveals
variable amplitude, chaotic to low continuous reflectors. The base of seismic Unit 6 (H6)
is marked by a truncation surface.
Figure 6 (a) Isopach map of Unit 5. (b) Seismic facies map of Unit 5. The maximum thickness of Unit 5 is
located in the SSE part of the study area, consists of seismic facies G and E. Seismic facies E occurred
from the mid-slope to the downslope part of the study area. Seismic faceis D mainly occurred in the upper
part.
3.4.3.2. Seismic Unit 5
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