scholarly journals The effects of subduction termination on the continental lithosphere: Linking volcanism, deformation, surface uplift, and slab tearing in central Anatolia

Geosphere ◽  
2017 ◽  
Vol 13 (6) ◽  
pp. 1788-1805 ◽  
Author(s):  
Jonathan R. Delph ◽  
Bizhan Abgarmi ◽  
Kevin M. Ward ◽  
Susan L. Beck ◽  
A. Arda Özacar ◽  
...  
2005 ◽  
Vol 40 ◽  
pp. 174-178 ◽  
Author(s):  
Joseph S. Walder ◽  
Dennis C. Trabant ◽  
Michelle Cunico ◽  
Suzanne P. Anderson ◽  
Robert S. Anderson ◽  
...  

AbstractIce-dammed Hidden Creek Lake, Alaska, USA, outbursts annually in about 2–3 days. As the lake fills, a wedge of water penetrates beneath the glacier, and the surface of this ‘ice dam’ rises; the surface then falls as the lake drains. Detailed optical surveying of the glacier near the lake allows characterization of ice-dam deformation. Surface uplift rate is close to the rate of lake-level rise within about 400 m of the lake, then decreases by 90% over about 100 m. Such a steep gradient in uplift rate cannot be explained in terms of ice-dam flexure. Moreover, survey targets spanning the zone of steep uplift gradient move relative to one another in a nearly reversible fashion as the lake fills and drains. Evidently, the zone of steep uplift gradient is a fault zone, with the faults penetrating the entire thickness of the ice dam. Fault motion is in a reverse sense as the lake fills, but in a normal sense as the lake drains. As the overall fault pattern is the same from year to year, even though ice is lost by calving, the faults must be regularly regenerated, probably by linkage of surface and bottom crevasses as ice is advected toward the lake basin.


2017 ◽  
Vol 18 (5) ◽  
pp. 1866-1888 ◽  
Author(s):  
Mary R. Reid ◽  
W. Kirk Schleiffarth ◽  
Michael A. Cosca ◽  
Jonathan R. Delph ◽  
Janne Blichert-Toft ◽  
...  

2021 ◽  
Author(s):  
Maud J.M. Meijers ◽  
Gilles Y. Brocard ◽  
Ferhat Kaya ◽  
Cesur Pehlevan ◽  
Okşan Başoğlu ◽  
...  

<div> <p>The Central Anatolian Plateau (CAP, Turkey, elevation ca. 1-1.5 km) was established during the late Miocene. Prior to Pleistocene surface uplift of its southern margin (Tauride Mountains), a southern margin orographic barrier with similar-to-present elevations (ca. 2 km) existed between 8 and 5 Ma.</p> </div><div> <p>To unravel the interactions between tectonics and Earth surface processes, we quantify biotic and abiotic parameters for the late Miocene to Pliocene. As the CAP exposes presently incised fluvio-lacustrine sedimentary rocks of well-dated Miocene to Pliocene age, the region provides an excellent archive for reconstructing past landscape dynamics, such as surface uplift, lake hydrology, and drainage integration. Within this established framework, we now reconstruct the late Miocene to Pliocene ecosystem by measuring clumped isotope (Δ<sub>47</sub>) temperatures of carbonate formation and δ<sup>13</sup>C and δ<sup>18</sup>O values of paleosol carbonate and fossil mammal tooth enamel. Collectively, our data allow for the reconstruction of paleoclimate, vegetation types (C<sub>3</sub> vs. C<sub>4</sub>), mammalian diet, landscape heterogeneity, and seasonality.</p> </div><div> <p>The first clumped isotope-derived paleotemperatures indicate a large (8 <span>°</span>C) temperature difference at ca. 5.5 Ma between lacustrine carbonate from the Mediterranean coastal region (Adana Basin; ca. 26 ± 1.8 <span>°</span>C) and paleosol carbonate from the central Anatolian interior (ca. 18 ± 1.7 <span>°</span>C), which likely reflects the higher elevation of the CAP. Soil carbonate δ<sup>13</sup>C values from the plateau interior (13 sites, N= 344, ca. 10 to 2 Ma) are much higher between ca. 8 and 5 Ma (ca. –3 to 0 ‰) than earlier or later in time (ca. –8 to –5 ‰), which indicates the presence of a significant component of C<sub>4</sub> vegetation, characterized by wooded grasslands and grasslands, during the latest Miocene. In contrast, C<sub>3</sub>-dominated vegetation reflecting more wooded environments were dominant at ca. 10 Ma and from 4 to 2 Ma. The increase in C<sub>4</sub> vegetation during the late Miocene is coeval with surface uplift of the southern CAP margin, whereas an increase of C<sub>3</sub> vegetation by the Pliocene could coincide with a phase of subsidence of the southern CAP margin prior to its final phase of Pleistocene surface uplift. Furthermore, we collected mammal tooth enamel samples (equid, bovid, rhinocerotid, suid) from 11 individuals at one ca. 9 Ma-old and one latest Miocene-Pliocene<span> fossil site. </span>δ<sup>13</sup>C and δ<sup>18</sup>O values indicate the mammals at the two nearby fossil sites had varying diets and therefore access to different vegetation and water supplies. We are currently improving the stratigraphic framework and dating of these fossil sites, as well as obtaining tooth enamel δ<sup>13</sup>C and δ<sup>18</sup>O values of 44 more individuals to further constrain paleoenvironmental conditions and eventually the causality between tectonics and Earth surface processes in central Anatolia.</p> </div><div> <p><span>References:</span><strong><span> </span></strong><span>Meijers et al., 2018a: Palaeo3, doi: 10.1016/j.palaeo.2018.03.001; Meijers et al., 2018b: EPSL, doi: 10.1016/j.epsl.2018.05.040; Huang, Meijers et al., 2019: J of Biogeography, doi: 10.1111/jbi.13622; Meijers et al., 2020: Geosphere, doi: 10.1130/GES02135.1</span></p> </div>


2020 ◽  
Author(s):  
Ye Tian ◽  
Feng Huang ◽  
Jifeng Xu ◽  
Baodi Wang ◽  
Han Liu ◽  
...  

2018 ◽  
Author(s):  
David Fernández-Blanco

Orogenic plateaus have raised abundant attention amongst geoscientists during the last decades, offering unique opportunities to better understand the relationships between tectonics and climate, and their expression on the Earth’s surface.Orogenic plateau margins are key areas for understanding the mechanisms behind plateau (de)formation. Plateau margins are transitional areas between domains with contrasting relief and characteristics; the roughly flat elevated plateau interior, often with internally drained endorheic basins, and the external steep areas, deeply incised by high-discharge rivers. This thesis uses a wide range of structural and tectonic approaches to investigate the evolution of the southern margin of the Central Anatolian Plateau (CAP), studying an area between the plateau interior and the Cyprus arc. Several findings are presented here that constrain the evolution, timing and possible causes behind the development of this area, and thus that of the CAP. After peneplanation of the regional orogeny, abroad regional subsidence took place in Miocene times in the absence of major extensional faults, which led to the formation of a large basin in the northeast Mediterranean. Late Tortonian and younger contractional structures developed in the interior of the plateau, in its margin and offshore, and forced the inversion tectonics that fragmented the early Miocene basin into the different present-day domains. The tectonic evolution of the southern margin of the CAP can be explained based on the initiation of subduction in south Cyprus and subsequent thermo-mechanical behavior of this subduction zone and the evolving rheology of the Anatolian plate. The Cyprus slab retreat and posterior pull drove subsidence first by relatively minor stretching of the crust and then by its flexure. The growth by accretion and thickening of the upper plate, and that of the associated forearc basins system, caused by accreting sediments, led to rheological changes at the base of the crust that allowed thermal weakening, viscous deformation, driving subsequent surface uplift and raising the modern Taurus Mountains. This mechanism could be responsible for the uplifted plateau-like areas seen in other accretionary margins. ISBN: 978-90-9028673-0


2005 ◽  
Vol 13 (1) ◽  
pp. 161-170 ◽  
Author(s):  
Paul De Paepe ◽  
Luc Moens ◽  
José De Donder
Keyword(s):  

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