We obtained the 3D crustal velocity structure of the Central Alborz region in northern Iran using local earthquake tomography. We used P-wave arrival-time data recorded by stations from three national observatories consisting of the Iranian Seismological Center, the International Institute of Earthquake Engineering and Seismology, and the Tehran Disaster Management and Mitigation Organization along with data from a temporary network. The P-wave arrival-times from local earthquakes have been used to produce a 3D tomographic velocity model of the Central Alborz using the inversion code SIMULPS. The low-velocity sedimentary layer in the upper crust is up to ~4 km thick. Our results show a mid-crustal interface at ~15 ± 2.5 km depth. This interface shows a pronounced uplift at a relatively aseismic part of the Mosha fault that might have the potential to produce an earthquake with magnitude M_w ~ 6–6.5. Independent gravity modeling was carried out, which confirms the location of the anomaly at the relatively aseismic part of the Mosha fault. A small uplift of the mid-crustal interface beneath the junction of the Mosha and North Tehran faults close to the city of Tehran might indicate a similar anomaly. Various resolution and synthetic tests (e.g., checkerboard, Resolution Matrix Diagonal, and data uncertainties) were performed and support the reliability of the resolved anomalies.

我们使用局部地震层析成像技术获得了伊朗北部中部阿尔伯兹地区的3D地壳速度结构。我们使用了由伊朗地震学中心，国际地震工程与地震学研究所和德黑兰灾难管理与减灾组织组成的三个国家天文台的台站记录的P波到达时间数据，以及来自临时网络的数据。来自本地地震的P波到达时间已被用于使用反演代码SIMULPS生成中央阿尔伯兹的3D层析速度模型。上地壳的低速沉积层厚约4 km。我们的结果表明，在约15±2.5 km深度处存在中壳界面。_{w ^}  〜6-6.5。进行了独立的重力模拟，这确定了异常位置在莫沙断层的相对地震部分。靠近德黑兰市的莫沙断裂带和北德黑兰断裂带交界处下方的中地壳界面略有隆升，可能表明存在类似的异常现象。进行了各种分辨率和综合测试（例如，棋盘格，对角线分辨率矩阵和数据不确定性），并支持已解决异常的可靠性。