## 3 Results
### Pockmark Field
#### 3.1.5 Active Faulting in the Pockmark Field  
Active faults were identified from lateral displacements on reflectors in the high-resolution seismic profiles and from linear seafloor displacements in multibeam data. Integration of bathymetry and seismic profiles allowed measurement of fault orientation, dip, vertical displacement (fault throw) and fault activity. Faults were picked line-by-line on seismic profiles and clustered into two groups: (1) \"major\" faults that appear in many seismic profiles, showing a sufficient displacement of the Holocene/Pleistocene boundary and can be correlated to bathymetric features and (2) \"minor\" faults that appear locally in few seismic profiles without bathymetric expression (Figures 15 and 16). In total, six normal faults were recorded in the area. Figure 15: High-resolution seismic profile showing six normal faults that affect the structure of the layers. Enhanced Reflectors and Acoustic Turbid Zones are present in the upper sequence. (F: Fault; AT.F: Agia Triada Fault; ER: Enhanced Reflector; ATZ: Acoustic Turbid Zone; HOL/PL: Holocene Pleistocene boundary). In the northern sector of the field, a group of linearly arranged pockmarks is located along the upper part of a slope with a bathymetric difference of 4 to 10 m. This \"chain\" of pockmarks has a WSW-ENE orientation and a length of about 1 km. Seismic profiles perpendicular to this slope revealed the trace of a WSW-ENE trending, south-dipping normal fault that causes a bathymetric difference of up to 5 m. The vertical throw of this normal fault, as measured by the offset of the Holocene/Pleistocene reflector surface, is about 15 m, with a small variation along strike. The thickening of the lithoseismic stratigraphy in the hanging-wall block of this fault, combined with the progressive decrease of the vertical displacement toward the surface, indicates its syn-sedimentary activity during the Holocene (Figure 15). This WSW-ENE striking normal fault is the offshore continuation of the AT.F that runs through the southern areas of the city of Patras [76; 77; 78]. At a distance of 750 m, south of the AT.F, an almost parallel topographic lineament occurred. Seismic profiles running perpendicular to this structure showed that it is located along the trace of a normal fault (F\({}_{1}\) fault in Figure 15) that causes deepening of the seabed bathymetry to the north. The dip of this normal fault decreases from west to east and does not affect the sediments near the coast. The vertical throw, as measured from the displacement of the Holocene/Pleistocene seismic surface west of the field, is about 12 m. This fault is antithetic to the AT.F, while it does not seem to continue toward the east near the coastline. Both faults, AT.F and F\({}_{1}\), fracture outcrop at the seabed and exhibit offsets that are clearly visible on a multibeam bathymetric map (Figure 3). A characteristic of this area is the arching of the Holocene sediments on the football block of this fault, possibly due to gas accumulations above the ATZ below. A parallel, less extensive topographic lineament exists 250 m north of AT.F. Seismic profiles revealed another normal fault (F\({}_{5}\) in Figure 15) that dips to the north, forming a conjugate, divergent overlapping transfer zone with the AT.F. The throw measured from  
Figure 16: (**a**) Tectonic map of the pockmark field area. (**b**) Three seismic profiles parallel to the shoreline from shallow (**i**); medium (**ii**) to deep water (**iii**) showing the highest displacement, with a characteristic reverse drag on the hanging-wall block in the medium-depth seismic profile (AT.F: Agia Triada Fault; F: fault). the offset of the Holocene/Pleistocene seismic surface west of the field is about 5 m. This fault is also antithetic to the AT.F and F4 fault, forming an uplifted horst-anticlinal structure (Figure 15).