Page 3 - FGamberi1992

This depocentre is the resull of interaction
between two separate extensional episodes, the
younger of which had the greater effect.
o·
Figure 6. Line G-33 showing an ex1ensional faull
bounding 10 the wes1 depocentre 2. The basai
detachment marked by the arrows has a depth of 2.8
s. and is shallower lhan in Fig.7. Triangle indicates
the tie with line G-60.
o-
•
Figu re 7. Linc G-60 p3ssing pcrpendicular to
Figure 6. A NE-SW striking <1nd NW dipping fault
occurs 10 1hc south or lhe centrai d~pocentrc of basi n
2. Thc sh;1llow dc tach rrh!nl of thc fault that bounds
thc dcpoc~nlcr to thc w.::st (Figure 6) is marked by
Gth-c:na.rrow.s. Th c trian!!lc inù ic11cs thc tie with line
~
o·
Figure 8. Line G-30 illustrating an eastward
thickening and of the Plio-Quaternary succession in
thc northernmost sidc of basin l. Folding may be
c.aused by inversion of a SW dippin o
~
lault bctween arrows. Note abrupt change in Plio-
Quatcrnary thickness in the castcrn part of the
profilc.
In thc northcmmost depocentrc, structures
with N-S. NE-SW. and E-W strike are present.
Scdimcntary successions are markedly
different (Fig. 8). with a greater thickness
usually to the south.
This could indicate strike-slip activity or
the inversion of south-dipping extensional
faults.
Basin 2. The eastern depocentre is
bounded by extensional faults with strikes
parallel to that of the basin elongation.
Control faults dip southwest. The sedimentary
fill of this depocentre was affected by two
shortening episodes the first of which
occurred early in the basin evolution and
originated a small thrustt at the basin centre
(Fig. 9, arrow A). The second episode is quite
recent and folded the sediments at the basin
margin (Fig. 10, arrow B).
Figure 9. Line G-69 showing two shortening
episodes within sedimcnts of southcrnmost basin 2.
The older (arrow A) has a NW-SE strike, parallel 10
th~t of thc profile, thc younger (arrow B) has a NE-
SW strike. The tic with line G-37 is indicated by the
triangle.
Thc western dcpoce ntrc is controlled by
NW -SE trcnding faults that di p southwest.
Shortcning affectcd thc scdimentary fili and
originatcd structurcs with strikc paraUel to the
basin axis.
Discussion and Conclusions
Prcliminary analysis indicatcs thc presence
of Plio-Quatcrnary basins superposed onto
thc Maghrcbian FTB. offshore western Sicily.
o-
extensional
Figure lO Line G-37 lying perpendicular to the older
compressional structure of Fig. 9. This structure has
a NW-SE strike. The triangle marks the tic with line
G-69
Basin 2 has the most complex
deformational pattern along its southeastern
side where its orientation changes from NW-
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