Figure 1. Tectonic setting of Turkey. The majority of Turkey is on the Anatolian block at the plate boundary zone of the Eurasian, Arabian, and African plates. Tectonic activities are mainly controlled by the right-lateral strike-slip North Anatolian fault and the left-lateral strike-slip East Anatolian fault. GPS velocities relative to a fixed Eurasian plate (Blewitt et al., 2018) show counter-clockwise rotational movement of the Anatolian block, and the Arabian plate moving north. Most of the representative focal mechanism solutions since 1990 (U.S. Geological Survey Earthquake Hazards Program, 2017) are crustal deformations with strike-slips or extensional slips. Earthquakes since Feb 06, 2023 are clustered around the East Anatolian fault zone. 圖一：土耳其的構(gòu)造背景。土耳其大部分處在歐亞-阿拉伯-非洲板塊交界處的安納托利亞地塊上，構(gòu)造運(yùn)動(dòng)主要受右行走滑北安納托利亞斷層和左行走滑東安納托利亞斷層的控制。相對(duì)于固定的歐亞板塊的GPS速度（Blewitt et al., 2018）顯示安納托利亞地塊正進(jìn)行逆時(shí)針旋轉(zhuǎn)，而阿拉伯板塊正在向北運(yùn)動(dòng)。1990年以來代表性的震源機(jī)制（USGS地震災(zāi)害項(xiàng)目組，2017）主要是地殼走滑、伸展地震。2023年2月6日以來的地震集中在東安納托利亞斷層帶一代。 Figure 2. GPS coseismic displacement of the two large earthquakes (Blewitt et al., 2018) show left-lateral strike-slips, with the deformations being more NE-SW for the Mw 7.75 (blue arrows) along the East Anatolian fault and more E-W for the Mw 7.55 (red arrows) along the Cardak fault. Focal mechanisms (U.S. Geological Survey Earthquake Hazards Program, 2017) show left-lateral strike-slip along the aforementioned faults as well as E-W extensions along the Savrun and the Dead Sea faults. Despite the appearance of the Mw 7.75 hypocenter near the Dead Sea fault zone, InSAR data from the ALOS-2 satellite (Geospatial Information Authority of Japan, 2023) show that the Mw 7.75 actually ruptured the East Anatolian fault with more than 5 meters of slip. Black double opposing arrows show the maximum horizontal stress compiled from the world stress map (Heidbach et al., 2016) in N-S to NNE-SSW directions near the faults, consistent with the left-lateral strike-slip and E-W extensions. 圖二：GPS同震形變(Blewitt et al., 2018)顯示7.75級(jí)地震沿東安納托利亞斷層的東北-西南向左行走滑和7.55級(jí)地震沿Cardak斷層的東西向左行走滑。震源機(jī)制(USGS地震災(zāi)害項(xiàng)目組，2017)也顯示沿前述斷層的左行走滑，以及沿Savrun斷層和死海斷層的東西向伸展形變。盡管7.75級(jí)地震的震中顯示在死海斷層附近，ALOS-2衛(wèi)星的InSAR數(shù)據(jù)(日本空間信息局，2023)顯示此次7.75級(jí)地震實(shí)際上破裂的是東安納托利亞斷層并造成超過5米的位移。相對(duì)的黑色箭頭顯示編譯于世界應(yīng)力地圖的最大水平應(yīng)力(Heidbach et al., 2016)為南北向或北北東-南南西方向，也與左行走滑和東西向伸展一致。 ?Figure 3. Scaled sum of the shake intensities (with a 5% increase for the Mw 7.55) and population density by province in the most affected areas in Turkey and Syria. Denser and darker colors show that Gaziantep and Hatay provinces are probably the most affected areas with high population. 圖三：兩次地震的烈度之和（給7.55級(jí)地震賦予了5%的增益）與土耳其敘利亞兩國的分省人口密度。更深更暗的顏色顯示Gaziantep和Hatay兩省可能是受地震影響最大而人口密集的省份。 Figure 4. InSAR coseismic displacements of the Turkey earthquakes on 02/06/2023 from ALOS-2 satellite, from Geospatial Information Authority of Japan (2023). 圖四：2023年2月6日土耳其地震的ALOS-2衛(wèi)星InSAR同震形變，來自日本空間信息局（2023）。
Blewitt, G., Hammond, W.C., and Kreemer, C., 2018, Harnessing the GPS Data Explosion for Interdisciplinary Science: Eos, v. 99, doi:10.1029/2018EO104623.
Geospatial Information Authority of Japan, 2023, The 2023 Turkey earthquake: crustal deformation detected by ALOS-2 data:, https://www.gsi.go.jp/cais/topic20230206-e_Turkey.html.
Heidbach, O., Rajabi, M., Reiter, K., Ziegler, M., and Team, W., 2016, World Stress Map Database Release 2016: GFZ Data Services, doi:10.5880/WSM.2016.001.
U.S. Geological Survey Earthquake Hazards Program, 2017, Advanced National Seismic System (ANSS) Comprehensive Catalog of Earthquake Events and Products:, doi:10.5066/F7MS3QZH.
