TY  - JOUR
A1  - Aygül, Mesut
A1  - Okay, Aral I.
A1  - Oberhänsli, Roland
A1  - Ziemann, Martin Andreas
T1  - Thermal structure of low-grade accreted Lower Cretaceous distal turbidites, the Central Pontides, Turkey: insights for tectonic thickening of an accretionary wedge
JF  - Turkish journal of earth sciences = Türk yerbilimleri dergisi
N2  - Albian-Turonian subduction-accretionary complexes are exposed widely in the Central Pontides. A major portion of the accretionary complexes is made up of a metaflysch sequence consisting of slate/phyllite and metasandstone intercalation with blocks of marble, Na-amphibole bearing metabasite, and serpentinite. The metaflysch sequence represents distal parts of a large Lower Cretaceous submarine turbidite fan deposited on the Laurasian active continental margin that was subsequently accreted and metamorphosed during the Albian. Raman spectra of carbonaceous material of the metapelitic rocks revealed that the metaflysch consists of metamorphic packets with distinct peak metamorphic temperatures. The majority of the metapelites are low-temperature (ca. 330 degrees C) slates characterized by lack of differentiation of the graphite (G) and D2 defect bands. They possibly represent offscraped distal turbidites along the toe of the Albian accretionary wedge. Other phyllites are characterized by a slightly pronounced G band with a D2 defect band occurring on its shoulder. Peak metamorphic temperatures of these phyllites are constrained to 370-385 degrees C. The phyllites are associated with a strip of incipient blueschist facies metabasites and are found as a sliver within the offscraped distal turbidites. We interpret the phyllites as underplated continental sediments together with oceanic crustal basalt along the basal decollement. Tectonic emplacement of the underplated rocks into the offscraped distal turbidites was possibly achieved by out-of-sequence thrusting causing tectonic thickening and uplift of the wedge.
KW  - Pontides
KW  - distal turbidites
KW  - offscraping
KW  - underplating
KW  - low-grade metamorphism
KW  - graphitization
KW  - Raman microspectroscopy
Y1  - 2015
U6  - https://doi.org/10.3906/yer-1504-4
SN  - 1300-0985
VL  - 24
IS  - 5
SP  - 461
EP  - 474
PB  - Tübitak
CY  - Ankara
ER  - 
TY  - JOUR
A1  - Scharf, Anke
A1  - Handy, Mark R.
A1  - Ziemann, Martin Andreas
A1  - Schmid, Stefan M.
T1  - Peak-temperature patterns of polyphase metamorphism resulting from accretion, subduction and collision (eastern Tauern Window, European Alps) - a study with Raman microspectroscopy on carbonaceous material (RSCM)
JF  - Journal of metamorphic geology
N2  - Raman microspectroscopy on carbonaceous material (RSCM) from the eastern Tauern Window indicates contrasting peak-temperature patterns in three different fabric domains, each of which underwent a poly-metamorphic orogenic evolution: Domain 1 in the northeastern Tauern Window preserves oceanic units (Glockner Nappe System, Matrei Zone) that attained peak temperatures (T-p) of 350-480 degrees C following Late Cretaceous to Palaeogene nappe stacking in an accretionary wedge. Domain 2 in the central Tauern Window experienced T-p of 500-535 degrees C that was attained either within an exhumed Palaeogene subduction channel or during Oligocene Barrovian-type thermal overprinting within the Alpine collisional orogen. Domain 3 in the Eastern Tauern Subdome has a peak-temperature pattern that resulted from Eo-Oligocene nappe stacking of continental units derived from the distal European margin. This pattern acquired its presently concentric pattern in Miocene time due to post-nappe doming and extensional shearing along the Katschberg Shear Zone System (KSZS). T-p values in the largest (Hochalm) dome range from 612 degrees C in its core to 440 degrees C at its rim. The maximum peak-temperature gradient (70 degrees Ckm(-1)) occurs along the eastern margin of this dome where mylonitic shearing of the Katschberg Normal Fault (KNF) significantly thinned the Subpenninic- and Penninic nappe pile, including the pre-existing peak-temperature gradient.
KW  - doming
KW  - Eastern Alps
KW  - high-pressure and Barrovian-type metamorphism
KW  - orogen-parallel extension
KW  - peak-temperature pattern
KW  - Raman microspectroscopy
Y1  - 2013
U6  - https://doi.org/10.1111/jmg.12048
SN  - 0263-4929
VL  - 31
IS  - 8
SP  - 863
EP  - 880
PB  - Wiley-Blackwell
CY  - Hoboken
ER  -