Evidence for widespread creep on the flanks of the Sea of Marmara transform basin from marine geophysical data

Abstract

aboard the R/V K. Piri Reis, which is operated by Dokuz Eylül University (Izmir, Turkey) (Fig. 1A). MCS data were acquired on a 450 m streamer in 2008, and on a 700 m or 1500 m streamer in 2010. The common midpoint (CMP) spacing was 3.125 m, streamer depth was 3-4 m, and ABSTRACT"Wave" fi elds have long been recognized in marine sediments on the fl anks of basins and oceans in both tectonically active and inactive environments. The origin of "waves" (hereafter called undulations) is controversial; competing models ascribe them to depositional processes, gravity-driven downslope creep or collapse, and/or tectonic shortening. Here we analyze pervasive undulation fi elds identifi ed in swath bathymetry and new high-resolution multichannel seismic (MCS) refl ection data from the Sea of Marmara, Turkey. Although they exhibit some of the classical features of sediment waves, the following distinctive characteristics exclude a purely depositional origin: (1) parallelism between the crests of the undulations and bathymetric contours over a wide range of orientations, (2) steep fl anks of the undulations (up to ~40°), and (3) increases in undulations amplitude with depth. We argue that the undulations are folds formed by gravity-driven downslope creep that have been augmented by depositional processes. These creep folds develop over long time periods (≥0.5 m.y.) and stand in contrast to geologically instantaneous collapse. Stratigraphic growth on the upslope limbs indicates that deposition contributes to the formation and upslope migration of the folds. The temporal and spatial evolution of the creep folds is clearly related to rapid tilting in this tectonically active transform basin.on June 2, 2015 geology.gsapubs.org Downloaded from (TUBITAK)-BİDEB supported a six-month research visit for Kurt to LDEO and the University of Missouri. We thank the captains and crew of the R/V K. Piri Reis, who made the acquisition of these data possible despite challenging conditions. We thank Hydroscience Technologies Inc. for supporting the seismic systems of R/V K. Piri Reis, Landmark for ProMAX software, and Seismic

Distribution, morphology and triggers of submarine mass wasting in the Sea of Marmara

“…More recently, a detailed analysis of these undulations, based on high resolution seismic data, concluded that these sediment waves correspond to slow gravity-driven downslope creep (Shillington et al, 2012).…”

“…Numerous studies of the seafloor morphology of the Sea of Marmara identified sediment waves (Okay et al, 1999;Imren et al, 2001 andShillington et al, 2012) and mass wasting features (e.g. Gazioğlu et al, 2002;Altinok et al, 2003;Gazioğlu et al, 2005;Gökçeoğlu et al, 2009;Görür and Çağatay, 2010;Özeren et al, 2010).…”

“…Sediment wave fields occur in various places on the seafloor of the Sea of Marmara and have been investigated by different authors (Okay et al, 1999;Imren et al, 2001;Shillington et al, 2012) proposing different interpretations. More recently, a detailed analysis of these undulations, based on high resolution seismic data, concluded that these sediment waves correspond to slow gravity-driven downslope creep (Shillington et al, 2012).…”

Mass wasting processes along the Owen Ridge (Northwest Indian Ocean)

“…Two morphological features that could be the result of the interaction of slope instability with other processes (such as bottom currents or fluid escapes) were further identified along the Owen Ridge: undulating (Lee et al, 1981;Field and Barber, 1993;Baraza and Ercilla, 1996;Gardner et al, 1999;Corregiari et al, 2001;Lee et al, 2002), or as the result of a combination of deformation and depositional processes Gonthier et al, 2002;Shillington et al, 2012). Sub-circular depressions similar to the ones observed along the Owen Ridge are described on the Malpelo Ridge (Lonsdale and Fornari, 1980) and on the Carnegie Ridge (Michaud et al, 2005) in the Pacific Ocean.…”

Estimation of successive coseismic vertical offsets using coeval sedimentary events – application to the southwestern limit of the Sea of Marmara's Central Basin (North Anatolian Fault)

“…The different results concern (1) deep fluids expulsion related to seismotectonic activity (Géli et al, 2008;Tary et al, 2012;Burnard et al, 2012, etc. ); (2) mass wasting and creep (Zitter et al, 2012;Shillington et al, 2012); (3) deep sedimentation specificities Sari and Çagatay, 2006;Çagatay et al, 2012;Drab et al, 2012); and (4) detection and dating of historical coseismic scarps (Armijo et al, 2005;Uçarkuş, 2010). Historical tsunami reports and modeling (Altinok et al, 2011;Hébert et al, 2005) complete these different data, taking into account the fact that these phenomena are not systematically associated with Armijo et al (2002Armijo et al ( , 2005, and GPS kinematics from McClusky et al (2000) and Reilinger et al (2006).…”