Growth structures, piggy-back basins and growth strata of the Georgian part of the Kura foreland fold–thrust belt: implications for Late Alpine kinematic evolution

Abstract

The Kura foreland fold–thrust belt is located in the northern part of the active collisional Lesser Caucasus orogenic belt associated with Arabia–Eurasia convergence. This belt is the best example of mountain-building processes in late Alpine time. Seismic reflection profiles show that the Kura foreland fold–thrust belt of the eastern Caucasus is an active thin-skinned fold–thrust belt and is represented by fault-bend folds, fault-propagation folds and duplexes. Analysis of growth strata in seismic profiles and oil well data from the Kura foreland fold–thrust belt documents that the evolution of deformation has been continuing during the last c. 14–15 myr (since the Middle Miocene), together with the thrust system kinematics. The geometry of the growth strata is associated with footwall synclines and piggy-back basins. Compressional deformation on the Kura foreland began in the Middle Miocene (Chokrakian) and reached its maximum rate at the end of the Miocene (c. 5 Ma).

Geodynamics, seismicity, and seismic hazards of the Caucasus

“…The Caucasus located in the central part of the mobile Alpine-Himalayan belt is the result of a continental collision between the AR-EU plates (Dewey et al, 1973;Khain, 1975;Adamia, 1975;Dercourt et al, 1986;Zonenshain and Le Pichon, 1986;Zonenshain et al, 1987;Philip et al, 1989;Okay and Şahintürk, 1997;Allen et al, 2004;Vincent et al, 2007;Zakariadze et al, 2007;Sosson et al, 2010aSosson et al, , 2017Adamia et al, 2011Adamia et al, , 2017Albino et al, 2014;Cavazza et al, 2017;Alania et al, 2017). The ongoing interaction of these plates controls the present geodynamics and the seismicity of the Caucasus (McKenzie, 1972;Jackson and McKenzie, 1988;Ambraseys and Jackson, 1998;Berberian and Yeats, 1999;Allen et al, 2004;Panahi, 2006;Karakhanyan et al, 2013Karakhanyan et al, , 2017Şeşetyan et al, 2018).…”

Tectonic Evolution of the Eastern Black Sea and Caucasus: an introduction

“…Oligocene-Miocene shortening is widely recognized throughout the study area, including by Avagyan et al (2016) in the Khoy area of NW Iran and Alania et al (2015) in the Kura fold-thrust belt in SE Georgia and Azerbaijan. Alania et al (2015) report the formation of Oligocene syn-compressional basins. This element of the tectonic evolution of the study area and the mechanism of formation of the Cenozoic sedimentary basins are documented elsewhere, specifically by Sheremet et al (2016b) and Sydorenko et al (2016) in the eastern Black Sea region and Crimea and by Avagyan et al (2016) in Iran, van der Boon et al (2015) in Azerbaijan and Hippolyte et al (2015) in eastern Turkey.…”

“…The underlying Eocene volcanic rocks are part of a very long belt of similar rocks, which include those discussed by Sahakyan et al (2016) and Hippolyte et al (2015) and which continue to the SE through Iran. Alania et al (2015) focus on the latest stages of the Cenozoic compressional phase of tectonics in SE Georgia and adjacent parts of Azerbaijan ( Fig. 1; area 7) by exploring the tectonic structures in the Miocene and younger subsurface formations revealed by seismic reflection profiling, rather than by outcrops of older formations.…”

Landslides near Enguri dam (Caucasus, Georgia) and possible seismotectonic effects

“…GPS data and plate tectonic models indicate that the Greater and Lesser Caucasus are tectonically very active, with ongoing mountain building processes comprising complex defor-mation with vertical and horizontal strain partitioning (Rebai et al, 1993;Koçyigit et al, 2001;Reilinger et al, 1997Reilinger et al, , 2006Tan and Taymaz, 2006;Pasquaré et al, 2011). These processes result from the convergence and continent-continent collision that is still developing between the Eurasian and African-Arabian plates (Avagyan et al, 2010;Adamia et al, 2017) (Fig. 1).…”