Karaoğlan F. (Executive), Karataş B., Gülyüz E.
TUBITAK Project, 2023 - 2025
The Livingstone island is located in the southern part of the South
Shetland Islands shaped by the opening of the Bransfield Strait in a back-arc
setting as a result of the subduction of the Antarctic plate (former Phonex
Plate). The island has an area of 798 km2 including Miers Bluff Formation, Mt.
Bowles Formation, Barnard Point Tonalite, Inot Point Formation. The magmatic
intrusions formed in an arc setting started during Middle Jurassic and ended
during Miocene.
The tectonic setting of the island led to the trench parallel faulting
on the island. The low-temperature thermochronology (LTT) data from the
magmatic and sedimentary rocks are limited to two apatite Fission Track (AFT)
studies. The LTT data pre-dates the opening of the current back-arc setting and
are getting younger from north to south. The AFT ages obtained from the Miers
Bluff formation range from 25 to 32 Ma, with one exception of 17 Ma, whereas
the AFT ages obtained from the Barnard Point Tonalite range from 16 Ma to 22
Ma.
In this study, the magmatic and sedimentary rocks will be subject to
zircon (ZHe) and apatite (AHe) U-Th/He and AFT analyses to enlighten the
tectono-thermal evolution of the island. The samples will collect regarding the
faulting on the island. The ZHe ages closure temperature is 200C corresponding
to 8-10km depth, the closure temperature of AFT is 110-120C corresponding to
3-4 km depth, whereas the AHe ages closure temperature is 60-70C corresponding
to 2-3 km depth. The overall LTT data will yield a continuous uplift from
8-10km depth to 2-3 km depth.
The
available LTT data indicates an Oligocene-Miocene uplift of the region,
however, the AHe ages will have a potential of young tectonic events.