Origin, structural geometry, and development of a giant coherent slide: The South Makassar Strait mass transport complex

Abstract

The South Makassar Strait mass transport complex (MTC) covers an area of at least 9000 km 2 and has a total volume of 2438 km 3 . It is composed of a shale-dominated sedimentary unit with high water content. Seismic refl ection data across the South Makassar Strait MTC show that it displays relatively coherent internal sedimentary stratigraphy that in the toe region is deformed into welldefi ned thrust-related structures (imbricates, ramps and fl ats, fault bend folds). It is one of the largest known coherent MTCs. The bowl-shaped central core region is as much as 1.7 km thick, and is confi ned to the west and east by 355° and 325° trending (respectively) lateral ramps in the upper slope area that pass via oblique ramps into a northeastsouthwest-trending frontal ramp area. The core area passes via the lateral, oblique, and frontal ramps into an extensive, thin (tens of meters thick) region of the MTC (the lateral and frontal apron areas) that are internally deformed by thrusts, normal faults, and thrust faults reactivated as normal faults. The MTC anatomy can be divided into extension headwall, translational, toe, fl ank, lateral apron, and frontal apron domains. The headwall region is located in the upper slope area of the Paternoster platform; the main body of the slide is in the deep-water region of the Makassar Strait. The complex is interpreted to be triggered by uplift of the platform area (accompanied by inversion), and/or basin subsidence, which caused seaward rotation of ~2° of the Paternoster platform in the Plio-cene. Variable uplift promoted sliding dominantly from the eastern and western margins of the headwall. The internal fault patterns of the MTC show that extension in the upper slope to lower slope in the core area changes downslope to compressional structures in the toe domain and apron. Later extensional collapse of parts of the compressional toe area occurred with negative inversion on some faults. The coherent internal stratigraphy, and evidence for multiphase extension in the eastern headwall area, suggests that the ~6-7 km of shortening in the toe region of the MTC occurred at a slow strain rate. Therefore, this type of MTC does not have the potential to generate tsunamis.

True Volumes of Slope Failure Estimated From a Quaternary Mass‐Transport Deposit in the Northern South China Sea

“…Considering that the two previous cases (the Storegga Slide and the study area) have similar turbidite rates, and other slope failures (volume > 1,000 km 3 ) located in deepwater regions with gentle slope gradients are similar to the northern South China Sea, the turbidite rates calculated in this work can be used as a reference to large slope failures. A large amount of turbidites (e.g., 1,890-5,292 km 3 for Makran Accretionary Complex) would therefore be expected in large-scale slope failures (see Table S2 for the possible turbidite contents of large-scale slope failures [imaged volume ≥ 1,000 km 3 ]; Armandita et al, 2015;Burg et al, 2008;Calvès et al, 2015;Chaytor et al, 2010;Collot et al, 2001;Denne et al, 2013;Dingle, 1977Dingle, , 1980Frey-Martinez et al, 2005;Gee et al, 2006;Haflidason et al, 2004;Hjelstuen et al, 2007;Lamarche et al, 2008;Lee et al, 2004;Leslie & Mann, 2016;Mosher et al, 2012;Niemi et al, 2000;Owen et al, 2010;Piper et al, 1997;Popenoe et al, 1993;Torelli et al, 1997;Trincardi & Argnani, 1990;Vanneste et al, 2006;Wynn et al, 2000). It is worth to note that there are still some uncertainties about the volume estimates for turbidites in the study area.…”

Tectonic and oceanographic process interactions archived in Late Cretaceous to Present deep‐marine stratigraphy on the Exmouth Plateau, offshore NW Australia

“…On the other hand, the timing and distribution of gravitydriven deposition has been used to reconstruct the tectonosedimentary evolution of passive (e.g. Armandita, Morley, & Rowell, 2015;Clark et al, 2012;Gamboa, Alves, Cartwright, & Terrinha, 2010;Heinio & Davies, 2006;Scarselli et al, 2016;Thöle, Kuhlmann, Lutz, & Gaedicke, 2016), and active margins (e.g. Alfaro & Holz, 2014;Covault, Romans, Graham, Fildani, & Hilley, 2011;Normark, Piper, & Sliter, 2006;Pérez et al, 2016;Richardson, Davies, Allen, & Grant, 2011;Romans, Normark, McGann, Covault, & Graham, 2009;Romero-Otero, Slatt, & Pirmez, 2010;Schwenk & Spieß, 2009;Sømme, Piper, Deptuck, & Helland-Hansen, 2011;Vinnels, Butler, McCaffrey, & Paton, 2010;Völker, Geersen, Behrmann, & Weinrebe, 2012).…”

Link between growth faulting and initiation of a mass transport deposit in the northern Taranaki Basin, New Zealand

“…From quick inspection of the MTD the transport direction is not immediately apparent. Many seismic reflection‐based studies of MTDs have identified various kinematic indicators that can help constrain the direction, magnitude and mode of transport and classify MTDs (Frey‐Martinez et al ., ; Moscardelli & Wood, ; Bull et al ., ; Armandita et al ., ). Different kinematic indicators occur in the three classic domains of MTDs (Fig.…”

“…The kinematic indicators typically associated with this domain are the presence of oblique and lateral ramps, with oblique displacement or strike‐slip senses of motion (e.g. Frey‐Martinez et al ., ; Bull et al ., ; Armandita et al ., ). Internally the translational domain can be chaotic, exhibit a mixture of thrust and extensional structures, or be a relatively undeformed domain that has undergone lateral translation on the basal detachment.…”

“…This MTD, here referred to the Karewa Fault MTD, exhibits an unusual geometry, where it is much wider than it is long (Fig. b), this is in clear contrast to the typical geometries of MTDs that are generally longer than they are wide (Frey‐Martinez et al ., ; Moscardelli & Wood, ; Meckel et al ., ; Armandita et al ., ). The dimensions of the Karewa Fault MTD are strongly influenced by the presence of the underlying extensional Karewa growth fault (Figs a, and ).…”