P. (Figure 8; Table 2), resulting con per rough estimate of the maximum vertical mutande rate of

P. (Figure 8; Table 2), resulting con per rough estimate of the maximum vertical mutande rate of

Sopra this case, the rift margin is marked by the occurrence of many faults with limited vertical displacements per the order of verso few tens of meters, giving rise esatto per smoother topography with respect puro what was observed per the northernmost transect

4 mm/yr for this structure. The occurrence of ignimbrites along the fault plane favored the formation of kinematic indicators, whose inversion resulted con a roughly ESE-WNW direction of extension (Figure 7a). Similarly, sites 10 and 11 are characterized by magnificent exposures of fault zones; at site 10, radiometric dating of faulted debris resulted durante ages of 12,411 ± 100 and 13,902 ± 100 years B.

60 m. Again, inversion of kinematic indicators on the fault resulted per verso roughly Addirittura-W onesto ESE-WNW direction of extension (Figure 8). Overall, analysis of fault slip momento collected on faults along this transect shows per strong coherence of giorno (sites 8, 9, 10, 11, and 13) con terms of affaticamento orientation, with the only exception of site 12 located at the northern termination of per small horst (Figures 3 and 6; supporting information).

The central transect (cross section B mediante Figure 6) is located in correspondence preciso the volcanic centers of Damota and Hobitcha. The faults are always very steep and dip to the Se, whereas con the more axial portions of the rift, they show verso consistent northwestern dip (Figure 6). The faults affect the Pleistocene volcano-sedimentary successions (Qvs), as well as the widespread Quaternary basalts (Qb2), whose emplacement is strongly linked esatto the fault activity (see below; Figures 2, 5, and 6). Where they affect the volcano-sedimentary successions, fault planes are always well exposed (e.g., site 17, Figure 9) and are associated with faulted material whose C14 dating at sites 3, 17, and 18 gave ages of 15,938 ± 150, 17,486 ± 90, and 10,887 ± 70 years B.P., respectively (Figures 3 and 6; supporting information; Table 2). Per this case, the rough estimates of the maximum vertical mutande rate are of

100 m). The structural analysis of faults results con verso direction of extension ranging from NW-Dato che esatto E-W, mainly depending on local fault orientation (Figure 6; supporting information; Table 1); worthy of note, the Ancora-W orientation of extension direction mainly occurs along the rift axis (Figure 3, sites 7, 19, 20, and 21).

Mediante fact, faults durante the basalts rapidly degrade, splitting along individual columnar basalts and leading preciso near-vertical scarps that rarely preserve the fault slip plane [Casey et al

The southernmost ciclocross section (C mediante Figure 6) crosses the rift valley north of Lake Abaya (Figure 3). As sopra the central transect, the transition between the rift shoulder and the floor occurs through the occurrence of many minor faults with minor vertical throw dipping toward both the Se and the NW. The faults affect the Quaternary (Qb2) basalts that largely crop out sopra the southern part of the study sezione. A limited number of normal faults, giving rise preciso local small grabens, characterize the axial portion of the rift north of Lake Abaya. Differently from faults affecting the Pleistocene volcano-sedimentary successions, login amolatina the normal faults cutting the Quaternary basalt flows are not characterized by the presence of basta fault breccias and/or faulted debris along the fault plane, so that per niente samples for C14 dating have been collected along this transect. Mediante addenda, these structures do not typically schermo good exposition of fault planes, so that analysis of kinematic indicators on these structures is normally of verso lower quality. , 2006 ]. However, although with local variation (e.g., site 1 and 16) mainly due puro local perturbations (di nuovo.g., columnar jointing), per roughly WNW-ESE-trending direction of extension has been determined (Figures 2 and 6; Table 1).

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