To estimate a non-uniform effective elastic thickness (Te) of lithosphere across Korean Peninsula and the Surrounding Seas (KPSS), we employ gravitational coherence analysis between gravity anomalies and topography/bathymetry data in the Fourier domain. Exploring crustal flexure and effective elastic thickness variations can offer insights into flexural strength, and evolutionary mechanics of the lithosphere under Ulleung Basin (UB). Our approach involves two scenarios: a large study area spanning the KPSS, and a more targeted investigation focused on UB. Dividing the study area into overlapping windows enables us to recover non-uniform Te values over the targeted regions. The UB study area is divide to 200 km by 200 km windows, and KPSS is divided to 400 km, 600 km, and 800 km windows to recover both short wavelengths and long wavelengths of Te. Our results reveal a Te range of 843 km for KPSS and recovered Te range from 1 to 10 km for UB. The estimated elastic thickness values in southern part of this basin are smaller compared to central and northern parts. These findings are consistent with prior estimations and comparative studies within the region, improving the understanding of UB's lithospheric properties. The recovered Te values for UB (Te<6km) suggests a young and weak oceanic lithosphere under this region. The alignment between recovered Te configuration and tectonic features in KPSS displays a large-scale lithospheric structure.

中文翻译：

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基于重力相干性的东海郁陵盆地岩石圈弯曲和有效弹性厚度


为了估计朝鲜半岛及周边海域 （KPSS） 岩石圈的非均匀有效弹性厚度 （Te），我们在傅里叶域中的重力异常和地形/测深数据之间采用引力相干分析。探索地壳弯曲和有效弹性厚度变化可以深入了解郁陵盆地 （UB） 下岩石圈的弯曲强度和演化力学。我们的方法涉及两种情况：跨越 KPSS 的大型研究区域，以及针对 UB 的更有针对性的调查。将研究区域划分为重叠的窗口使我们能够恢复目标区域上不均匀的 Te 值。UB 研究区域分为 200 km x 200 km 窗口，KPSS 分为 400 km、600 km 和 800 km 窗口，以恢复 Te 的短波长和长波长。我们的结果显示，KPSS 的 Te 范围为 843 km，UB 的恢复 Te 范围为 1 至 10 km。与中部和北部相比，该盆地南部的估计弹性厚度值较小。这些发现与该地区先前的估计和比较研究一致，提高了对 UB 岩石圈特性的理解。UB 的恢复 Te 值 （Te<6km） 表明该区域下方有一个年轻而弱的海洋岩石圈。KPSS 中恢复的 Te 构型与构造特征之间的对齐显示了大尺度的岩石圈结构。