 |
| Titel |
Multi-parameter analysis of seismoturbidites in the Kumburgaz Basin of Sea
of Marmara: Implications for creeping versus locked Central High segment of
the North Anatolian Fault |
| VerfasserIn |
Nurettin Yakupoğlu, Gülsen Uçarkus, K. Kadir Eriş, M. Namik Çağatay, Pierre Henry, Burak Yalamaz, Asen Sabuncu, Dursun Acar |
| Konferenz |
EGU General Assembly 2016
|
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 18 (2016) |
| Datensatznummer |
250121796
|
| Publikation (Nr.) |
 EGU/EGU2016-644.pdf |
|
|
|
|
|
| Zusammenfassung |
| Sediment sequences deposited in active transform basins provide valuable archives
of earthquake-triggered co-seismic sedimentation. A better understanding of the
relationship between offshore fault ruptures and Seismoturbidites would have direct
implications for earthquake hazard assessment. Submerged section of the North
Anatolian Fault in the northern Sea of Marmara basin, which experienced more than 55
(Ms>6.8) earthquakes in the last 2000 years, poses a unique laboratory to study such
kind of sync-tectonic history. Following the devastating 1999 Izmit and Duzce
earthquakes (Mw = 7.4/7.2 respectively), a major seismic gap is now along the offshore
branch of the NAF in the Sea of Marmara. The segments that control the Cinarcik
and Kumburgaz basins in the Sea of Marmara have not ruptured during the 20th
century.
This study focusses on the Kumburgaz basin, which is located along the central segment
of the NAF, and its less-known linkage to historical earthquakes, particularly to Ms>7 1509
and 1766 earthquakes. The main objective of this study is to test the two alternative
hypotheses of a creeping versus locked central High segment by determining the
frequency and timing of earthquake triggered turbidite units in the Kumburgaz
basin.
A 21-m-long piston core recovered in Kumburgaz basin during the Marsite cruise in 2014
is analysed at high resolution in order to identify the discrete turbidite-homogenite units
(T–H units). The piston core reveals 22 T–H units where several packages consist
of a sharp basal contact and multiple fining upward beds of sand to coarse silt as
characteristically seen in most Seismoturbidite units. We initiated a systematic
study of T-H units with the objectives of establishing criteria for identification of
Seismoturbidites by analysing the physical, mineralogical and chemical composition of
the piston core. The density and magnetic susceptibility changes along the core
are analysed by Multi-Sensor Core Logger (MSCL). High detrital input proxies
(Ca/Ti, Fe, and K) are determined with the μ-XRF core scanner equipped with X-ray
radiography. Radiographic images reveal the abrupt changes of the sedimentary structures
and smear-slide analysis point out the possible sources of sediments for different
turbidites.
Keywords: Sea of Marmara, Seismoturbidite, Kumburgaz Basin, Paleoseismology |
|
|
|
|
|
|