C. Glover et A. Robertson, Neotectonic intersection of the Aegean and Cyprus tectonic arcs: extensional and strike-slip faulting in the Isparta Angle, SW Turkey, TECTONOPHYS, 298(1-3), 1998, pp. 103-132
The Isparta Angle and adjacent Antalya Bay areas constitute an important se
gment of the eastern Mediterranean region, located at the intersection of t
he southward-convex Aegean and Cyprus arcs. Some recent tectonic maps show
the Isparta Angle as a NW-SE compressional lineament extending eastwards in
to the Kyrenia Range of northern Cyprus. However, fault data from the onsho
re Isparta Angle, together with offshore shallow seismic reflection data, s
how that the present morpho-tectonic setting is dominated by extension. The
last phase of compression to affect the area studied in the Late Miocene,
was accompanied by regional nappe emplacement (Lycian Nappes). Onshore, fau
lt planes, measured from fault zones bounding both the limbs and the core o
f the Isparta Angle are oriented predominantly NE-SW, NW-SE and N-S. Superi
mposed slickenfibres show that reverse faults were succeeded, in turn, by r
ight-lateral faults, then by normal faults. The fault phases are dated by s
tratigraphical and geomorphological evidence. Reverse faults date from the
Late Miocene, or earlier compressional deformation, whereas the right-later
al faults mainly developed during latest Miocene-Early Pliocene. Normal fau
lting dominated from the Late Pliocene-Recent. An interpretation of shallow
seismic reflection data shows that Antalya Bay is characterised by a NW-SE
-trending asymmetrical graben system that has continued to be active. Durin
g the Late Miocene-Early Pliocene right-lateral strike-slip resulted from s
heer along the eastern termination of a zone of extension and rotation that
characterises the western Aegean. This shear was focused in a N-S directio
n by inherited zones of structural weakness in the basement (Antalya Comple
x). The switch to NE-SW extension in the Late Pliocene-Quaternary relates t
o a regional change in stress direction throughout the Aegean region and wa
s accompanied by strong uplift of the Bey Daglari region of the Taurus Moun
tains, bordering the Isparta Angle in the west. The Isparta Angle is the li
nk between: (a) the extensional province of western Turkey bounded to the s
outh by the actively subducting Hellenic are; and (b) the uplifted Anatolia
n plateau bounded to the south by the Cyprus subduction zone. Understanding
the Miocene to Recent tectonic development helps elucidate the kinematics
of the region. The new structural data presented lend no support for recent
suggestions that the Isparta Angle and Antalya Bay represent parts of a re
gional compressional zone related to plate collision. (C) 1998 Elsevier Sci
ence B.V. All rights reserved.