TY - JOUR A1 - Jara-Munoz, Julius A1 - Melnick, Daniel T1 - Unraveling sea-level variations and tectonic uplift in wave-built marine terraces, Santa Maria Island, Chile JF - Quaternary research : an interdisciplinary journal N2 - The architecture of coastal sequences in tectonically-active regions results mostly from a combination of sea-level and land-level changes. The objective of this study is to unravel these signals by combining sequence stratigraphy and sedimentology of near-shore sedimentary sequences in wave-built terraces. We focus on Santa Maria Island at the south-central Chile margin, which hosts excellent exposures of coastal sediments from Marine Isotope Stage 3. A novel method based on statistical analysis of grain-size distributions coupled with fades descriptions provided a detailed account of transgressive-regressive cycles. Radiocarbon ages from paleosols constrain the chronology between >53 and similar to 31 cal ka BP. Because the influence of glaciations can be neglected, we calculated relative sea-level curves by tying the onset of deposition on a bedrock abrasion platform to a global sea-level curve. The observed depositional cycles match those predicted for uplift rates between 1.2 and 1.8 m/ka. The studied sedimentary units represent depositional cycles that resulted in reoccupation events of an existing marine terrace. Our study demonstrates wave-built marine terrace deposits along clastic shorelines in temperate regions can be used to distinguish between tectonic uplift and climate-induced sea-level changes. KW - Marine terraces KW - Wave-built terraces KW - Terrace reoccupation KW - Tectonic uplift KW - Sea-level change KW - Coastal sedimentation Y1 - 2015 U6 - https://doi.org/10.1016/j.yqres.2014.10.002 SN - 0033-5894 SN - 1096-0287 VL - 83 IS - 1 SP - 216 EP - 228 PB - Elsevier CY - San Diego ER - TY - JOUR A1 - Jara-Munoz, Julius A1 - Melnick, Daniel A1 - Brill, Dominik A1 - Strecker, Manfred T1 - Segmentation of the 2010 Maule Chile earthquake rupture from a joint analysis of uplifted marine terraces and seismic-cycle deformation patterns JF - Quaternary science reviews : the international multidisciplinary research and review journal N2 - The segmentation of major fault systems in subduction zones controls earthquake magnitude and location, but the causes for the existence of segment boundaries and the relationships between long-term deformation and the extent of earthquake rupture, are poorly understood. We compare permanent and seismic-cycle deformation patterns along the rupture zone of the 2010 Maule earthquake (M8.8), which ruptured 500 km of the Chile subduction margin. We analyzed the morphology of MIS-5 marine terraces using LiDAR topography and established their chronology and coeval origin with twelve luminescence ages, stratigraphy and geomorphic correlation, obtaining a virtually continuous distribution of uplift rates along the entire rupture zone. The mean uplift rate for these terraces is 0.5 m/ka. This value is exceeded in three areas, which have experienced rapid emergence of up to 1.6 m/ka; they are located at the northern, central, and southern sectors of the rupture zone, referred to as Topocalma, Carranza and Arauco, respectively. The three sectors correlate with boundaries of eight great earthquakes dating back to 1730. The Topocalma and Arauco sectors, located at the boundaries of the 2010 rupture, consist of broad zones of crustal warping with wavelengths of 60 and 90 km, respectively. These two regions coincide with the axes of oroclinal bending of the entire Andean margin and correlate with changes in curvature of the plate interface. Rapid uplift at Carranza, in turn, is of shorter wavelength and associated with footwall flexure of three crustal-scale normal faults. The uplift rate at Carranza is inversely correlated with plate coupling as well as with coseismic slip, suggesting permanent deformation may accumulate interseismically. We propose that the zones of upwarping at Arauco and Topocalma reflect changes in frictional properties of the megathrust resulting in barriers to the propagation of great earthquakes. Slip during the 1960 (M9.5) and 2010 events overlapped with the similar to 90-km-long zone of rapid uplift at Arauco; similarly, slip in 2010 and 1906 extended across the similar to 60-km-long section of the megathrust at Topocalma, but this area was completely breached by the 1730 (M similar to 9) event, which propagated southward until Carranza. Both Arauco and Topocalma show evidence of sustained rapid uplift since at least the middle Pleistocene. These two sectors might thus constitute discrete seismotectonic boundaries restraining most, but not all great earthquake ruptures. Based on our observations, such barriers might be breached during multi-segment super-cycle events. (C) 2015 Elsevier Ltd. All rights reserved. KW - LiDAR KW - Subduction earthquakes KW - Marine terraces KW - Seismotectonic segmentation KW - Permanent uplift KW - Maule earthquake KW - Coastal uplift KW - TerraceM Y1 - 2015 U6 - https://doi.org/10.1016/j.quascirev.2015.01.005 SN - 0277-3791 VL - 113 SP - 171 EP - 192 PB - Elsevier CY - Oxford ER - TY - JOUR A1 - Yildirim, Cengiz A1 - Melnick, Daniel A1 - Ballato, Paolo A1 - Schildgen, Taylor F. A1 - Echtler, Helmut Peter A1 - Erginal, A. Evren A1 - Kiyak, Nafiye Gunec A1 - Strecker, Manfred T1 - Differential uplift along the northern margin of the Central Anatolian Plateau - inferences from marine terraces JF - Quaternary science reviews : the international multidisciplinary research and review journal N2 - Emerged marine terraces and paleoshorelines along plate margins are prominent geomorphic markers that can be used to quantify the rates and patterns of crustal deformation. The northern margin of the Central Anatolian Plateau has been interpreted as an actively deforming orogenic wedge between the North Anatolian Fault and the Black Sea. Here we use uplifted marine terraces across principal faults on the Sinop Peninsula at the central northern side of the Pontide orogenic wedge to unravel patterns of Quaternary faulting and orogenic wedge behavior. We leveled the present-day elevations of paleoshorelines and dated marine terrace deposits using optically stimulated luminescence (OSL) to determine coastal uplift. The elevations of the paleoshorelines vary between 4 +/- 0.2 and 67 +/- 1.4 m above sea level and OSL ages suggest terrace formation episodes during interglacial periods at ca 125, 190, 400 and 570 ka, corresponding to marine isotopic stages (MIS) 5e, 7a, 11 and 15. Mean apparent vertical displacement rates (without eustatic correction) deduced from these terraces range between 0.02 and 0.18 mm/a, with intermittent faster rates of up to 0.26 mm/a. We obtained higher rates at the eastern and southern parts of the peninsula, toward the hinterland, indicating non-uniform uplift across the different morphotectonic segments of the peninsula. Our data are consistent with active on- and offshore faulting across the Sinop Peninsula. When integrated with regional tectonic observations, the faulting pattern reflects shortening distributed over a broad region of the northern margin of the Central Anatolian Plateau during the Quaternary. KW - Orogenic Plateaus KW - Central Anatolian Plateau KW - Plateau margins KW - Central Pontides KW - Orogenic wedges KW - Black Sea KW - Marine terraces KW - Uplift rate Y1 - 2013 U6 - https://doi.org/10.1016/j.quascirev.2013.09.011 SN - 0277-3791 VL - 81 IS - 4 SP - 12 EP - 28 PB - Elsevier CY - Oxford ER -