Troodos Massif Uplift
Troodos Uplift Timing
Plio-Pleistocene sediments evince remarkable uplift
Age model for Troodos uplift based on
Lithostrat, biostrat & remnant magnetisation polarities in
- Upper Pliocene succession of Pissouri & Mesaoria Basins
- Pleistocene marine terraces bordering Troodos Massif
Field observations support this
Ilustrate the nature of
- Transition from shallow marine to fan-deltaic to terrestrial
- Subsequent formation of 4 marine terraces
--> Demonstrating Pleistocene uplift of Troodos
--> modified by orbital cycling controlled sealevel changes
Uplift driver?
Doming resulting from serpentinisation of harzburgite
Underthrusting of Eratosthenes Seamount beneath Cyprus
Mesaoria Basin
Chryssospiliotissa
Shallow marine, fossiliferous sand with
- fossils that are broken up
- hummocky cross beds
Fluvial conglomerate unconformably overlies
Interp
Rapid ∆ from shallow marine (Nicosia, 3.04-2.58) --> terrestrial
Disarticulated fossils & hummocky cross-stratification
--> sand deposited in high energy envmt
M-scale rootlets penetrating into sandstone
Athalassa Fm, Lachia
Hiatus before fanglomerate deposition
∴ Uplift must've started < 2.58 Ma
Palaeo-oyster reef patch underlain by chalky bioclastic sandstone
Sstone
has shell fragments, marble clasts, concretions
Large foresets suggesting N to S palaeoflow
= Athalassa ~2.58 - 1.07 Ma
Sstone
Interp
High terrigenous input suggests basin sufficiently shallow
--> to be affected by winds blowing off Kyrenia
Mega-sandwaves prograding S
Oyster interp
Last part of basin infill
Turbulent, hypersaline lagoonal envmt before Mesaoria basin formed
Apolos Fm, Xeri
Weakly imbricated conglomerate lens
Upper ophiolitic clasts found in
--> resistant silty/sandy seds either side of sstone unit
Apolos ~ 1.20-0.78 Ma
Interp: Non-marine deltaic system w overbank sediments
Mesaoria Basin emerging by this time
Pissouri Basin
Exposure @ Vasiliko records strong Troodos uplift (analogues in Mesaoria)
Thick massive marl unit
abundant shallow marine fossils
e.g. bivalves, gastropods, scaphopods
gives way to ophiolite-derived conglomerates
Interp:
Nicosia Fm unconformably overlain by Fanglomerates
Kakkaristra
Ophiolite-derived fan deltas ( not observed )
Age ~ 2.58 - 1.98 Ma
Further support uplift of Troodos
Fanglomerate
= main feature of drainage catchments
Conglomerates appear abruptly atop Pliocene
= planar/cross bedded
Erosion evidence often --> since they are non-marine
Regional Picture
Pleistocene
Eratosthenes Seamount arrives @ Cyprus SZ trench
Underthrusting - Seamount dives beneath trench
Drives uplift of Cyprus (Troodos/Kyrenia)
Why dome shape ?
Troodos would be deep marine if weren't for ES continental block subducting
Thought to represent serpentinite diapir
Serpentinite = hydrated ultramafic rocks risen from upper mantle exposed beneath
Cause Troodos Uplift
Result of both:
- Underthrusting of continental block (Eratosthenes Seamount)
- Focussed diapirism
(water input to SZ, hydrates mantle --> serpentinisation)
Summary
End Miocene
Seas flood back