Hayward, A.B.

English

The Lycian Tauride mountains of S. W. Turkey comprise a central
relatively autochthonous carbonate platform unit bordered by two
allochthonous units, the Lycian Nappes to the west and the Antalya
Complex to the east. From these allochthons thick sequences (`1,000 m)
of clastic sedimentary rocks were shed during the Miocene into a basin
floored by the subsided carbonate platform.

The Miocene sediments, exposed over ca. 2,500 km², have been
mapped at 1:25,000 scale; several hundred sedimentary logs have been
measured. Three new formations are recognised; the Kerner and Salir
Formation of Lower Miocene age, and the Kasaba Formation of Middle to
Upper Miocene age. Individual sedimentary facies are dominated by
coarse grained ophiolite-derived sediments of which redeposited and
sub aerial conglomerates and sandstones are the most widespread.

Along the western margin of the basin closest to the Lycian Nappe
front, the Kerner Formation consists of conglomerates and sandstones
deposited within a fan-delta. More distal sequences pass basinwares
into small submarine fan systems. The overlying Kasaba Formation was
deposited as an alluvial fan which prograded into a shallow sea.
Proximal alluvial fan deposits consist of dominantly clast-supported
massive conglomerates. These pass downslope into well defined
conglomerate-sandstone-mudstone fining-upward units. Shallow marine
shelf deposits are the lateral equivalents of this distal fan/braidplain
succession. Small patch reefs were developed in the marine sequence
during periods of reduced sediment supply.

In more central parts of the basin a thick (-800 m) sequence of
redeposited bioclastic breccias was derived from a contemporaneous
shallow water carbonate build-up. In the south, limestone conglomerates,
calcareous sandstones and mudstones, deposited in a submarine fan
environment document the uplift and sub aerial exposure of a large area
of the older carbonate platform.

Along the eastern margin of the basin the Salir Formation mainly
comprises conglomerates and sandstones deposited by sediment gravity
flows on small submarine fans. Above is a conglomerate dominated
sequence deposited on a fan-delta.

Palaeocurrents and downslope facies transitions demonstrate that
the ophiolitic sediments of the Kemer Formation were derived from the
Lycian Nappe ophiolitic unit to the west. Emplacement of this unit
onto the carbonate platform in Lower Miocene times evidently resulted
in irregular subsidence, with uplift and subaerial exposure of areas
of older carbonate platform rocks. The western margin of the basin
was progressively overthrust until the nappes finally came to rest in
the Late Miocene. The regressive-upwards sedimentary sequence reflects
both progressive basin infilling and Late Miocene lowering of sea level.

Along the eastern margin, palaeocurrent analysis and downslope
facies transitions show that the Antalya Complex was emplaced from the
east but only advanced a short distance beyond the eastern margin of
the basin. This is consistent with strike-slip dominated emplacement
of the Antalya Complex in contrast to the gravity driven emplacement
of the far travelled Lycian Nappes. As the Lycian Nappes and Antalya
Complex approached the basin from opposite directions their respective
ophiolite units must have been derived from separate, or at least
distinct, ocean basins to the north and south respectively, of the
carbonate platform now flooring the Miocene basin between them. The
wider plate-tectonic implications of this conclusion are investigated
briefly

Tertiary ophiolite-related sedimentation in SW Turkey

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