Sedimentary records of past earthquakes in Boraboy Lake during the last ca 600 years (North Anatolian Fault, Turkey)

Abstract

Multiproxy sedimentological analyses along 4.9 m-long sequence of Boraboy Lake, which is located on the central eastern part of the North Anatolian Fault (NAF), reveal the sedimentary traces of past large earthquakes in the region. The lake has a relatively large catchment area (10 km 2 ) compared to its size (0.12 km 2 ), which renders sedimentation sensitive to heavy rain/storm events. Accordingly, the background sedimentation, which is composed of faintly laminated reddish/yellowish brown clayey silt, is frequently interrupted by organic-rich intercalations probably due to heavy rain/storm events transporting terrestrial plant remains from the densely vegetated catchment. In addition to frequent organic-rich intercalations, the background sedimentation is interrupted by four mass-wasting deposits (MWD) of which thickness range between 15 and 50 cm. to routine overloading and oversteepening on the delta front formed by the main inlet of the lake. In subaqueous paleoseismology, coevality of multi-location mass-wasting events is used as a criterion to assign a seismic A C C E P T E D M A N U S C R I P T ACCEPTED MANUSCRIPT2 triggering mechanism, and to rule out mass-wasting events due to routine overloading/oversteepening of subaqueous slopes. Within this context, Boraboy sequence provides a valuable example to discuss sedimentological imprints of single-vs. multi-source MWDs.

Flow dynamics at the origin of thin clayey sand lacustrine turbidites: Examples from Lake Hazar, Turkey

“…() and Avşar et al . (). Secondly, multistage remobilizations of one specific source, such as evidenced by Hunt et al .…”

“…For example, evidence of repeated subaqueous slope failures and turbidites in multiple Chilean and Argentinian lakes has been used to reconstruct large‐magnitude earthquake recurrence and palaeo‐intensities (Chapron et al ., ; Moernaut et al ., , ; Bertrand et al ., ; Waldmann et al ., ; Van Daele et al ., , ). Earthquake‐triggered turbidites in the Marmara Sea and the Boraboy Lake have been used to infer palaeo‐ruptures of the North Anatolian Fault threatening the city of Istanbul (McHugh et al ., ; Avşar et al ., ; Drab et al ., ). Sedimentary archives in Swiss Alpine lakes have also helped to characterize the recurrence of strong earthquakes in a moderate seismicity region (Becker et al ., ; Monecke et al ., ; Strasser et al ., , ; Beck, ).…”

Earthquake‐induced soft‐sediment deformations and seismically amplified erosion rates recorded in varved sediments of Köyceğiz Lake (SW Turkey)

“…Paleoseismic information from lake sediments has been commonly revealed through earthquake‐triggered soft‐sediment deformations [e.g., Migowski et al , ; Monecke et al , , ; Agnon et al , ; Beck , ; Kagan et al , ] and subaqueous mass‐wasting deposits [e.g., Schnellmann et al , ; Waldmann et al , ; Moernaut et al , , ; Van Daele et al , ; Avşar et al , ]. Recently, the potential of another tectono‐sedimentary process has been realized.…”

Changes in the biota and sediments of glacial Lake Koźmin, Poland, during the late Saalian (Illinoian)

“…shallowing or deepening of the basin, which in turn influenced the distance to the inflowing streams. Avsar et al (2010) showed that earthquakes of magnitude[7 can change the depth of a lake by as much as 1/3. Uplift in the area of a lake outlet of a few meters can result in considerable water-level rise (Ambraseys 1989).…”