The process and Mechanism of Ridge Jump in the South China Sea: Insights from Deep Seismic Velocity Structure

This archive includes seismic data from a wide-angle seismic survey line OBS2021-1, transecting the position of fossil mid-ocean ridge which is extinced at 25 Ma. The dataset was acquired in May of 2021, based on R/V "SHIYAN2", which belongs to the South China Sea Institute of Oceanology, Chinese Academy of Sciences. This survey focus on the deep seismics velocity structure and mechanism of ridge jump in the South China Sea. This 290 km long survey line comprises 30 four-components short-period OBS stations (sampling frequency: 100-250 Hz) deployed at 10 km intervals. 26 OBSs provide the seismic data for geophysical analysis, while three OBSs were unfortunately unrecovered and one OBS’s data is abnormal. The seismic source consisted of an array of four BOLT air guns with a total volume of 6,000 cubic inches, positioned approximately 10 m below sea level. Shots interval was 90 s with the vessel maintaining a speed of 4–5 knots. The seismic data is about P-wave phases travel-time of 26 OBSs, after necessary correction works.

本归档数据集包含广角地震（wide-angle seismic）测线OBS2021-1采集的地震数据，该测线横穿25 Ma前已停止活动的古洋中脊（fossil mid-ocean ridge）所在位置。本数据集于2021年5月由中国科学院南海海洋研究所的“实验2”号（R/V "SHIYAN2"）科考船完成采集。本次调查旨在揭示南海深部地震波速度结构与洋中脊跃迁的动力学机制。该测线全长290 km，共布设30台四分量短周期海底地震仪（OBS，Ocean Bottom Seismometer），台站间距为10 km，采样频率为100~250 Hz。其中26台OBS采集的有效地震数据可用于地球物理分析，遗憾的是有3台OBS未能回收，另有1台OBS的数据存在异常。本次调查采用由4台BOLT型气枪组成的阵列作为震源，总容积达6000立方英寸，震源布置于海面下约10 m处。放炮间隔为90 s，科考船航行速度维持在4~5节。经必要的校正处理后，本数据集包含26台OBS记录的P波震相走时数据。

搜集汇总

背景与挑战

背景概述

该数据集聚焦于南海洋中脊跳跃的过程与机制研究，基于2021年采集的深部地震速度结构数据。数据集包含一条横跨化石洋中脊的宽角地震测线，使用海底地震仪和气枪震源采集，主要提供26个站点的P波震相走时数据，用于地球物理分析。