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An intraplate earthquake of magnitude Mw 7.2 occurred on a NE-SW trending blind oblique thrust fault in accretionary orogen, the Van region of Eastern Anatolia on October 23, 2011. The aftershock seismicity in the Van earthquake was not continuous but, rather, highly discrete. This shed light on the chaotic nonuniformity of the event distribution and played key roles in determining the seismic coupling between the rupturing process and seismogeneity. I analyzed the discrete statistical mechanics of the 2011 Van mainshock-aftershock sequence with an estimation of the non-dimensional tuning parameters consisting of; temporal clusters (C) and the random (RN) distribution of aftershocks, range of size scales (ROSS), strength change (εD), temperature (T), P-value of temporal decay, material parameter R-value, seismic coupling χ, and Q-value of aftershock distribution. I also investigated the frequency-size (FS), temporal (T) statistics and the sequential characteristics of aftershock dynamics using discrete approach and examined the discrete evolutionary periods of the Van earthquake Gutenberg-Richter (GR) distribution. My study revealed that the FS and T statistical properties of aftershock sequence represent the Gutenberg-Richter (GR) distribution, clustered (C) in time and random (RN) Poisson distribution, respectively. The overall statistical behavior of the aftershock sequence shows that the Van earthquake originated in a discrete structural framework with high seismic coupling under highly variable faulting conditions. My analyses relate this larger dip-slip event to a discrete seismogenesis with two main components of complex fracturing and branching framework of the ruptured fault and dynamic strengthening and hardening behavior of the earthquake. The results indicate two dynamic cases. The first is associated with aperiodic nature of aftershock distribution, indicating a time-independent Poissonian event. The second is associated with variable slip model, varying loading rates and high seismic coupling along the ruptured area. This study concludes that the aperiodic statistical behavior of the Van aftershock sequence is one of the results of the time-independent Poissonian seismic deformation in the 2011 Van earthquake. [ABSTRACT FROM AUTHOR]

The peculiar one of the wedge-basins in E-Turkey is orogen-parallel Lake Van trough that is the deepest basin of the rotated portions of EAAC and thrust-bounded region. This lake is emplaced at N-end of Bitlis-Pötürge Massive (BP-M) along Muş suture, separating EAAC from BP-M. Lake Van region is a place where no mantle lid exists and hot astheno-sphere is doming, therefore, it has dome-shaped structure with the highest elevation (2 km), termed as Lake Van Dome. The domal pattern of the lake, in fact, is a morphological paradigm, well representing the surficial effects of delamination event, crustal consolidation and crust-forming process. Not surprisingly, outline anatomy of Lake Van Dome clearly exhibits an orogenic structure with its formation of the squashy basin and thus, both its morphological and limnological characteristics may imply basement reactivation and orogenic features of the Highlands rifting phenomena in the domal center of accretionary complex. Compared to other convergent lakes in major mountain ranges, such as Lake Baikal, Lake Van is not well studied, its geophysical characteristics are poorly documented and understood. An overall understanding of this lake as a complex highlands system is still lacking. This lack assumes utmost importance given the fact that Lake Van and surrounding highlands are prone to thinning convergent crust, decompressional melting magmatism and postcollisional opening of sutures, through which extensional magma propagates. These processes dictate how ascending magmatic materials are transported through the crust toward the surface and react with their surrounding environment within the volcanic or magmatic edifice. A sequential development of these events is focused on understanding the rich dynamics of multiple linked systems with weak basement coupling and with many internal variables that exhibit multiscale interactions be-neath the lake. Multi-component approach into basement and basin margin weakening highlights the relative roles of upper crustal tectonics, magmatism and the role of delamination and break off events, just beneath the lake. This generates deep insights into upper crust-driven seismicity and its results in basin response and subsequent impact on anisotropic variability of the convergent crust. The focus and objectives of Lake Van basin research are to provide a better understanding and overview of tectonic and magmatic processes in accretionary orogens and their role in the formation and evolution of the continental crust. Understanding post-collisional dynamics of accretionary wedges beneath Lake Van and their effect on Lake Van basin formation is essentially needed in this study. Multi channel seismic reflection profiles with a length of 850 km across Lake Van basin are collected by International Contiental Scientific Drilling Program, (PaleoVAN 2004 Project). Seismic structural interpretation showed that Plio-Quaternary structural development of the Lake Van basin is the result of two separate stress regimes: a Paleotectonic period of collision-compression and a Neotectonic period of extension/strike-slip deformation. Older structural elements bordering the lake have under-gone reactivation as sinistral and dextral strike-slip faults along the basin margins. The consequence of this stress reversal has been tectonic instability of accretionary wedges, a reactivation of convergent basement and a change in kinematic boundary conditions of the lake. As a result, during post-collisional period, Lake Van region has undergone basin block fragmentation and separation, implying an oblique opening of Muş suture, through which extensional magmatism propagated into the lake, intensely deformed lake sediments and created the huge magma-hydrothermal lacustrine system. The oblique opening of suture zone views the Highlands rifting phenomena in Lake Van, especially its S-margin. Based on the above observations, the structural form of the early compressional Lake Van basin is quite different from the present-day basin. An interplay of sedimentation and tectonics in Lake Van provided a new angle on basement reactivation, oblique motion of the upper crustal flakes and the strike-slip evolution of accretionary wedge basins in Turkic-type orogenic setting. Lake Van is the High-lands rifted basin produced by doming astheno-sphere, hence, Lake Van basin should be evaluated in a concept of the Highlands dynamics of hot and younger accretionary and Turkic-type orogens. Lastly, Lake Van basin shows tectonics and sedimentary characteristics of the Highlands Turkic type orogeny and thus, opens a new paradigm. [ABSTRACT FROM AUTHOR]