Flexural modeling of the elastic lithosphere at an ocean trench: A parameter sensitivity analysis using analytical solutions

Heterogeneous outer‐rise seismicity within the Izu–Bonin subduction zone and its tectonic implications

“…The flexural modelling studies show that Te of the subducting Pacific slab characterized by the magnetic anomaly age greater than 130 Ma, changes from 28 to 38 km. The value of Te is similar to the numerical value estimated in previous studies (e.g., Bodine & Watts, 1979; Contreras‐Reyes & Garay, 2018; Hunter & Watts, 2016; Levitt & Sandwell, 1995). Moreover, one thing to be noticed is that the varied Te of the subducting Pacific Plate is characterized by a tendency to decrease northwards (Figure 10), which is in contrast with a significant deepening of the outer‐rise seismicity (Figures 2 and 6).…”

“…Oakley, Taylor, and Moore (2008) proposed that nearly all of the flexural faults along the Izu–Bonin trench are sub‐parallel to the axis, consistent with the observation that magnetic anomaly lineations strike sub‐perpendicular to the trench, and, therefore, abyssal hill fabrics are not reactivated, except for a relief NNW‐trending graben south of 31°25′N. Contreras‐Reyes and Garay (2018) carried out the flexural modelling of the elastic lithosphere at the outer‐rise of Izu–Bonin subduction zone, which indicated that Te of the subducting slab is nearly 25–27 km. The flexural modelling of the plate calculated by Zhou, Lin, and Zhang (2018) revealed that the Te of the subducting plate decreases gradually towards the trench axis, with a maximum Te reduction of 22 km at the Izu–Bonin trench.…”

“…The uplift starts about 200-300 km from the trench axis (e.g., Bodine & Watts, 1979;Grevemeyer et al, 2005;Levitt & Sandwell, 1995), and the fitting degree between the observed and predicted data within 0-200 km distance from the trench axis determines the size of the squared root mean square (RMS). In terms of the squared RMS, the curve-fitting process is terminated when the modelling curves fit the data well, and previous studies (e.g., Bodine & Watts, 1979;Contreras-Reyes & Garay, 2018;Hunter & Watts, 2016;Levitt & Sandwell, 1995). Moreover, one thing to be noticed is that the varied Te of the subducting Pacific Plate is characterized by a tendency to decrease northwards (Figure 10), which is in contrast with a significant deepening of the outer-rise seismicity (Figures 2 and 6).…”

“…To analyse the trench tectonic loading and the long‐term strength of the lithosphere, the modelling the flexural deformation of the subducting plate at the trench is necessary (Contreras‐Reyes & Garay, 2018; Manrı́quez, Contreras‐Reyes, & Osses, 2014), which will contribute to understanding the dynamic mechanisms of heterogeneous outer‐rise seismicity within the Izu–Bonin subduction zone. Nevertheless, it is well known that the relationship between flexural deformation and outer‐rise seismicity is not so simple.…”

Styles of Trench‐Parallel Mid‐Ocean Ridge Subduction Affect Cenozoic Geological Evolution in Circum‐Pacific Continental Margins

“…30–40 Ma) of the Nazca slab that began to subduct beneath the south Patagonia (Chen et al., 2019; Seton et al., 2012). With the increasing of subducting slab dips, flexural deformation becomes significant and bending stress could then exceed the rock yield strength within the most deformed portions of the lithosphere (e.g., Contreras‐Reyes & Garay, 2018; Zhang et al., 2014). Therefore, identifying the role of slab dips on the trench‐parallel mid‐ocean ridge subduction is important to understand the genesis of contrasting geological evolution history in the western and eastern Pacific continental margins.…”