@article{ErbelloDoelessoMelnickZeilingeretal.2022,
  author    = {Erbello Doelesso, Asfaw and Melnick, Daniel and Zeilinger, Gerold and Bookhagen, Bodo and Pingel, Heiko and Strecker, Manfred},
  title     = {Geomorphic expression of a tectonically active rift-transfer zone in southern Ethiopia},
  series = {Geomorphology : an international journal on pure and applied geomorphology},
  volume    = {403},
  journal   = {Geomorphology : an international journal on pure and applied geomorphology},
  publisher = {Elsevier Science},
  address   = {Amsterdam [u.a.]},
  issn      = {0169-555X},
  doi       = {10.1016/j.geomorph.2022.108162},
  pages     = {20},
  year      = {2022},
  abstract  = {The Gofa Province and the Chew Bahir Basin of southern Ethiopia constitute tectonically active regions, where the Southern Main Ethiopian Rift converges with the Northern Kenya Rift through a wide zone of extensional deformation with several north to northeast-trending, left-stepping en-e \& PRIME;chelon basins. This sector of the Southern Main Ethiopian Rift is characterized by a semi-arid climate and a largely uniform lithology, and thus provides ideal conditions for studying the different parameters that define the tectonic and geomorphic features of this complex kinematic transfer zone. In this study, the degree of tectonic activity, spatiotemporal variations in extension, and the nature of kinematic linkage between different fault systems of the transfer zone are constrained by detailed quantitative geomorphic analysis of river catchments and focused field work. We analyzed fluvial and landscape morphometric characteristics in combination with structural, seismicity, and climatic data to better evaluate the tectono-geomorphic history of this transfer zone. Our data reveal significant north-south variations in the degree of extension from the Sawula Basin in the north (mature) to the Chew Bahir Basin in the south (juvenile). First, normalized channel-steepness indices and the spatial arrangement of knickpoints in footwall-draining streams suggest a gradual, southward shift in extensional deformation and recent tectonic activity. Second, based on 1-k(m) radius local relief and mean-hillslope maximum values that are consistent with ksn anomalies, we confirm strain localization within zones of fault interaction. Third, morphometric indices such as hypsometry, basin asymmetry factor, and valley floor width to valley height ratio also indicate a north to south gradient in tectonic activity, highlighting the importance of such a wide transfer zone with diffuse extension linking different rift segments during the break-up of continental crust.},
  language  = {en}
}
@article{BookhagenEchtlerMelnicketal.2006,
  author    = {Bookhagen, Bodo and Echtler, Helmut Peter and Melnick, Daniel and Strecker, Manfred and Spencer, Joel Q. G.},
  title     = {Using uplifted Holocene beach berms for paleoseismic analysis on the Santa Maria Island, south-central Chile},
  issn      = {0094-8276},
  doi       = {10.1029/2006gl026734},
  year      = {2006},
  abstract  = {Major earthquakes ( M > 8) have repeatedly ruptured the Nazca-South America plate interface of south-central Chile involving meter scale land-level changes. Earthquake recurrence intervals, however, extending beyond limited historical records are virtually unknown, but would provide crucial data on the tectonic behavior of forearcs. We analyzed the spatiotemporal pattern of Holocene earthquakes on Santa Maria Island (SMI; 37 degrees S), located 20 km off the Chilean coast and approximately 70 km east of the trench. SMI hosts a minimum of 21 uplifted beach berms, of which a subset were dated to calculate a mean uplift rate of 2.3 +/- 0.2 m/ky and a tilting rate of 0.022 +/- 0.002 degrees/ky. The inferred recurrence interval of strandline-forming earthquakes is similar to 180 years. Combining coseismic uplift and aseismic subsidence during an earthquake cycle, the net gain in strandline elevation in this environment is similar to 0.4 m per event},
  language  = {en}
}
@article{YildirimSchildgenEchtleretal.2013,
  author    = {Yildirim, Cengiz and Schildgen, Taylor F. and Echtler, Helmut Peter and Melnick, Daniel and Bookhagen, Bodo and Ciner, T. Attila and Niedermann, Samuel and Merchel, Silke and Martschini, Martin and Steier, Peter and Strecker, Manfred},
  title     = {Tectonic implications of fluvial incision and pediment deformation at the northern margin of the Central Anatolian Plateau based on multiple cosmogenic nuclides},
  series = {Tectonics},
  volume    = {32},
  journal   = {Tectonics},
  number    = {5},
  publisher = {American Geophysical Union},
  address   = {Washington},
  issn      = {0278-7407},
  doi       = {10.1002/tect.20066},
  pages     = {1107 -- 1120},
  year      = {2013},
  abstract  = {We document Quaternary fluvial incision driven by fault-controlled surface deformation in the inverted intermontane G{\"o}kirmak Basin in the Central Pontide mountains along the northern margin of the Central Anatolian Plateau. In-situ-produced Be-10, Ne-21, and Cl-36 concentrations from gravel-covered fluvial terraces and pediment surfaces along the trunk stream of the basin (the G{\"o}kirmak River) yield model exposure ages ranging from 71ka to 34645ka and average fluvial incision rates over the past similar to 350ka of 0.280.01mm a(-1). Similarities between river incision rates and coastal uplift rates at the Black Sea coast suggest that regional uplift is responsible for the river incision. Model exposure ages of deformed pediment surfaces along tributaries of the trunk stream range from 605ka to 110 +/- 10ka, demonstrating that the thrust faults responsible for pediment deformation were active after those times and were likely active earlier as well as explaining the topographic relief of the region. Together, our data demonstrate cumulative incision that is linked to active internal shortening and uplift of similar to 0.3mm a(-1) in the Central Pontide orogenic wedge, which may ultimately contribute to the lateral growth of the northern Anatolian Plateau.},
  language  = {en}
}
@article{MelnickBookhagenStreckeretal.2009,
  author    = {Melnick, Daniel and Bookhagen, Bodo and Strecker, Manfred and Echtler, Helmut Peter},
  title     = {Segmentation of megathrust rupture zones from fore-arc deformation patterns over hundreds to millions of years, Arauco peninsula, Chile},
  issn      = {0148-0227},
  doi       = {10.1029/2008jb005788},
  year      = {2009},
  abstract  = {This work explores the control of fore-arc structure on segmentation of megathrust earthquake ruptures using coastal geomorphic markers. The Arauco-Nahuelbuta region at the south-central Chile margin constitutes an anomalous fore- arc sector in terms of topography, geology, and exhumation, located within the overlap between the Concepcion and Valdivia megathrust segments. This boundary, however, is only based on similar to 500 years of historical records. We integrate deformed marine terraces dated by cosmogenic nuclides, syntectonic sediments, published fission track data, seismic reflection profiles, and microseismicity to analyze this earthquake boundary over 10(2) -10(6) years. Rapid exhumation of Nahuelbuta's dome-like core started at 4 +/- 1.2 Ma, coeval with inversion of the adjacent Arauco basin resulting in emergence of the Arauco peninsula. Here, similarities between topography, spatiotemporal trends in fission track ages, Pliocene-Pleistocene growth strata, and folded marine terraces suggest that margin-parallel shortening has dominated since Pliocene time. This shortening likely results from translation of a fore-arc sliver or microplate, decoupled from South America by an intra-arc strike-slip fault. Microplate collision against a buttress leads to localized uplift at Arauco accrued by deep-seated reverse faults, as well as incipient oroclinal bending. The extent of the Valdivia segment, which ruptured last in 1960 with an M-w 9.5 event, equals the inferred microplate. We propose that mechanical homogeneity of the fore-arc microplate delimits the Valdivia segment and that a marked discontinuity in the continental basement at Arauco acts as an inhomogeneous barrier controlling nucleation and propagation of 1960-type ruptures. As microplate-related deformation occurs since the Pliocene, we propose that this earthquake boundary and the extent of the Valdivia segment are spatially stable seismotectonic features at million year scale.},
  language  = {en}
}