On February 6, 2023, a magnitude 7.8 earthquake and subsequent strong seismic activity struck in Kahramanmaras region, causing over 50,000 deaths in Turkey and Syria. The earthquake resulted in a surface rupture of the East Anatolian Fault Zone (EAFZ) spanning approximately 300 km. To gain new insights into the neotectonic and current stress field in the region, we compiled 141 focal mechanism solutions (FMS) of earthquakes (with magnitude M ≥ 3) that occurred along the EAFZ between 05/01/2003 and 27/02/2023. Stress inversion, by using the Win-Tensor program, indicated a predominant strike-slip tectonic regime, with few normal and thrust events related to complex fault geometry along the principal displacement zone. The calculated pressure/tension axes in the first order stress field are mainly sub-horizontal, with a maximum horizontal compressive stress (SHmax) direction of N19 ± 9.9° E, which aligns well with the slip character of the EAFZ. To reconstruct the second and third order stress fields, the study area was subdivided into five zones based on their structures and geomorphological characteristics. Reduced stress tensors were obtained for each zone, indicating a small rotation of SHmax directions under a prevailing strike-slip faulting regime. The maximum (σ1) and minimum (σ3) stress axes are nearly horizontal; while the intermediate (σ2) stress axis is nearly vertical, consistent with a predominant strike-slip regime. The results show, also, that the Kahramanmaras earthquake was caused by the neotectonic reactivation of northeast-striking sinistral strike-slip fault, with a north–south-oriented maximum horizontal stress axis. The neotectonic activity along the EAFZ aligns well with the collision models between the Arabian and Eurasian plates. Finally, a detailed seismic hazard assessment is required for the EAFZ and nearby regions.

2023 年 2 月 6 日，卡赫拉曼马拉什地区发生里氏 7.8 级地震，随后发生强烈地震活动，导致土耳其和叙利亚超过 5 万人死亡。地震导致东安纳托利亚断裂带 (EAFZ) 的地表破裂，横跨约 300 公里。为了获得对该地区新构造运动和当前应力场的新见解，我们编制了 2003 年 1 月 5 日至 2023 年 2 月 27 日期间沿 EAFZ 发生的 141 个地震（震级 M ≥ 3）的震源机制解 (FMS) 。使用 Win-Tensor 程序进行的应力反演显示出主要的走滑构造状态，沿主位移带很少有与复杂断层几何形状相关的正向和逆冲事件。计算得到的一阶应力场压力/拉力轴主要为次水平方向，最大水平压应力（SHmax）方向为N19±9.9°E，与EAFZ的滑移特征吻合较好。为了重建二阶和三阶应力场，根据其结构和地貌特征将研究区细分为五个区域。每个区域都获得了减小的应力张量，表明在盛行的走滑断层作用下，SHmax 方向有小幅旋转。最大（σ1）和最小（σ3）应力轴接近水平；而中间（σ2）应力轴几乎垂直，与主要的走滑区域一致。研究结果还表明，卡赫拉曼马拉斯地震是由东北走向的左旋走滑断层的新构造活动引起的，最大水平应力轴为南北向。沿 EAFZ 的新构造活动与阿拉伯板块和欧亚板块之间的碰撞模型非常吻合。最后，需要对东亚自由区及附近地区进行详细的地震危险性评估。