Spatiotemporal evolution of brittle normal faulting and fluid infiltration in detachment fault systems: A case study from the Menderes Massif, western Turkey

Abstract

[1] K-Ar dating of fault rocks coupled with hydrogen isotope analysis allows constraining the timing of brittle faulting and the influx of meteoric fluids into such fault systems. Here we apply this approach to resolve the spatiotemporal activity of three detachment-fault systems in western Turkey and to evaluate how deep meteoric fluids infiltrated these fault systems. K-Ar ages of cataclasites and gouges from two detachment fault systems that accomplished the bivergent extension of the central Menderes Massif suggest diachronous brittle deformation. The Büyük Menderes detachment in the south was already active at 22 Ma, whereas the earliest brittle deformation recorded at the Gediz fault system in the north occurred at~9 Ma. K-Ar ages of secondary and splay faults indicate that both fault systems continued to be active until 4-3 Ma-consistent with rapid Pliocene cooling inferred from published thermochronological data. In the northern Menderes Massif, the boundary fault of the Simav graben became active at 17-16 Ma, after the end of faulting on the Simav detachment. Hydrogen isotope (dD) values of À109% to À87% for fault gouges, cataclasites, and mylonites document that meteoric fluids infiltrated the upper crustal normal faults and penetrated into the detachments and the uppermost levels of their mylonitic footwalls. This explains the ubiquitous retrogression of biotite to chlorite in extensional shear zones and the growth of chlorite in detachment-related cataclasites. Our results document that brittle normal faults were active over~20 Ma of the extensional history and provided effective pathways for meteoric fluids.

Timing and conditions of brittle faulting on the Silltal-Brenner Fault Zone, Eastern Alps (Austria)

“…1), with this profile corresponding to a telescoped crustal section through the detachment system. Similar to Hetzel et al (2013), H-isotope data were obtained from the Decker et al 2009). Locations are: A Stephansbrücke (samples SB1, SB2, SB3, SB4); B (sample BF1) and C (sample BF2), which are the two localities further south near Matrei.…”

Field evidence for normal fault linkage and relay ramp evolution: the Kırkağaç Fault Zone, western Anatolia (Turkey)

“…Recent tomographic and seismic studies reveal that slab edge processes and related backarc extension are the dominant driving force for western Anatolian and Aegean tectonics (Biryol, Beck, Zandt, & Özaçar, 2011;Faccenna, Bellier, Martinod, Piromallo, & Regard, 2006;Gans, Beck, Zandt, Biryol, & Ozacar, 2009;Gessner, Gallardo, Markwitz, Ring, & Thomson, 2013;Jolivet et al, 2013;Uzel et al, 2015;van Hinsbergen, Hafkenscheid, Spakman, Meulenkamp, & Wortel, 2005;van Hinsbergen, Kaymakçı, Spakman, & Torsvik, 2010). The main characteristics of this regional extension are as follows: (i) E-W trending detachment faults (Bozkurt, 2006;Bozkurt & Sözbilir, 2004;Emre, 1996;Emre & Sözbilir, 1997;Hetzel, Passchier, & Ring, 1995;Hetzel, Ring, & Akal, 1995;Hetzel et al, 2013;Işık, Seyitoğlu, & Çemen, 2003;Lips, Cassard, Sözbilir, Yılmaz, & Wijbrans, 2001;Sözbilir, 2001), (ii) E-W trending high angle normal faults that cut and offset the detachments (Bozkurt, 2003(Bozkurt, , 2004(Bozkurt, , 2007Bozkurt & Park, 1994;Çiftçi & Bozkurt, 2009;Gessner et al, 2001;Hetzel, Romer, Candan, & Passchier, 1998;Işık & Tekeli, 2001;Işık, Tekeli, & Seyitoğlu, 2004;Işık et al, 2003;Kaymakci, 2006;Koçyiğit, Yusufoğlu, & Bozkurt, 1999;Okay & Satır, 2000;Özkaymak, Sözbilir, & Uzel, 2011;…”

Late Cenozoic Extensional Tectonics in Western Anatolia: Exhumation of the Menderes Core Complex and Formation of Related Basins

“…However, this proposal does not include any recommendations related to the necessary sedimentary basin forming in the hanging wall of the main breakaway fault (Gessner et al, 2013). In this study, Gessner et al (2013) proposed a left directed shearing west of the Menderes Massif named the "Western Anatolian Transfer Zone".…”

“…However, this proposal does not include any recommendations related to the necessary sedimentary basin forming in the hanging wall of the main breakaway fault (Gessner et al, 2013). In this study, Gessner et al (2013) proposed a left directed shearing west of the Menderes Massif named the "Western Anatolian Transfer Zone". Seyito¤lu et al (2004) stated the necessity for a transfer zone linking the main breakaway fault north of Crete proposed by Faure et al (1991) with the Datça-Kale Main Breakaway Fault, and advocated that the Cyclades and Western Anatolia had a common extensional history (Seyito¤lu et al, 2004) (Figure 33, attached small sketch).…”