Relating the long-term and short-term vertical deformation across a transect of the forearc in the central Mexican subduction zone

Abstract

Earthquake-cycle deformation, which includes earthquake ruptures, interseismic strain, and transient slow slip events, spans spatial scales ranging from fractions of a meter to thousands of kilometers. Similarly, temporal scales range from seconds during an earthquake rupture to thousands of years of strain accumulation between earthquakes. We discuss results regarding the vertical crustal deformation associated with both slow and rapid crustal defor ma tion across a transect of the central Mexican subduction forearc in the Guerrero seismic gap, where the Cocos plate underthrusts the North America plate. This sector of the subduction zone is characterized by a flat-slab geometry with zones of sharp bending-unbending of the slab, irregularly distributed seismicity, and exceptionally large slow slip events. We used the river network, topography, geomorphic features, and morphometry on a transect across the forearc to assess Quaternary crustal deformation. The Papagayo drainage network shows that the forearc has been uplifted since the late Ceno zoic (~25 Ma), and that rates of uplift increased since the beginning of the Holocene. Uplift is not homogeneous but shows a trend of increase away from the coast. This vertical deformation is strongly influenced by subduction processes. Thus, the Papagayo River network is strongly controlled by Holocene earthquake cycle processes. This is particularly true for the southern section of the drainage basin, where E-W-striking left-lateral strike-slip faults with a vertical component offset the course of the main river. These faults are accommodating part of the oblique plate convergence at the Mexican subduction zone. We measured the height of a series of terraces and dated quartz extracts by optically stimulated luminescence, and we calculated long-term rates of uplift ranging from 0.5 to 4.9 mm/yr. We discuss associations of forearc topography, faults, and long-term crustal deformation with the Cocos slab geometry, distribution of slow slip events, and earthquake-cycle deformation.

Interseismic Loading of Subduction Megathrust Drives Long‐Term Uplift in Northern Chile

“…In the most simplistic model, the amount of slip during earthquakes should be balanced by the slip deficit that builds up in the interim period, at least once integrated over many earthquake cycles. However, along several subduction zones, the coastal domain, a region defined to extend from the coast to the continental shelf (Figure ), experiences long‐lived vertical displacement, either subsidence or uplift, over geological times (i.e., 10 5 –10 6 years), for example, as inferred from the geometry of raised terraces in Chile (Regard et al, ; Saillard et al, ), Japan (Matsu'ura, ), or Greece (Mouslopoulou et al, ) or the erosion patterns along rivers in Mexico (Ramírez‐Herrera et al, ). Such long‐term, irrecoverable deformation can be modeled with a purely plastic rheology, for instance, using critical taper theory (Davis et al, ).…”

Assessment of tectonic control on the development of low mountains moderate relief in the Outer Carpathians (Southern Poland)

“…and to the north of the Żywiec Basin, adjacent to the Soła Gorge (Figure 9). Previous studies proved that such catchments are indicative of high relative uplift rates (Table S1; e.g., Miller 1953;Bull and McFadden 1977;Schumm et al 2000;Burbank and Anderson 2001;Keller and Pinter 2002;Ruszkiczay-Rüdiger et al 2009;Pérez-Peña et al, 2010;Giaconia et al 2012;Matoš et al 2013;Różycka and Migoń, 2017;Gaidzik and Ramírez-Herrera 2017;Ramírez-Herrera et al 2018), also in areas of low tectonic activity (e.g., Badura et al 2003;Pánek 2004;Wołosiewicz 2018). For example, landscape analysis using similar geomorphometric indices suggested tectonic activity along the Sudetic Marginal Fault in the Sudetes (Badura et al 2003).…”

“…Minimum bulk erosion was calculated for the entire Soła catchment, as well as for the 47 analyzed tributary subcatchments. This index shows a minimum thickness of material eroded in each catchment (e.g., Giaconia et al 2012;Gaidzik and Ramírez-Herrera 2017;Ramírez-Herrera et al 2018). It was calculated as a difference between a theoretical pre-erosion surface and the DEM representing current relief, following the procedure by Brocklehurst and Whipple (2002).…”

“…Transient long profiles obtained for short rivers can be related to the low intensity of the erosive force of this type of rivers (Schumm et al 2000). Observed breaks in long profile lines could be related to local acceleration in tectonic activity (an active crustal fault with long recurrence period), as well as local variations in lithologic or climatic conditions (e.g., Schumm et al 2000;Kirby and Whipple 2012;Gaidzik and Ramírez-Herrera 2017;Ramírez-Herrera et al 2018).…”

“…Worldwide examples proved the usage of landscape analysis and geomorphometric indices, in particular, to quantify the tectonic deformation and derive variations in relative rock uplift across high strain rate areas, such as the western USA, Taiwan, Himalaya, Andes, forearc of subduction zones, etc. (e.g., Burbank and Anderson 2001;Whipple 2001, 2012;Keller and Pinter 2002;Gao et al 2013;Gaidzik and Ramírez-Herrera 2017;Ramírez-Herrera et al 2018;Wang et al 2019;García-Delgado and Velandia 2020), and in low strain rate areas like SE Spain (e.g., Pérez-Peña et al, 2010), the Vienna Basin and central Pannonian Basin (e.g., Ruszkiczay-Rüdiger et al 2009;Matoš et al 2013), Sudetes Mts. (e.g., Różycka and Migoń 2017).…”