“雪龙2”号国内首套Sea Ⅲ型海洋重力仪应用分析

PERFORMANCE ANALYSIS OF THE FIRST SET SEA Ⅲ GRAVIMETER ON XUELONG 2

Sea Ⅲ型海洋重力仪是Micro-g LaCoste公司在L&R SⅡ型重力仪原理基础上开发的新型摆杆-斜拉零长弹簧海洋重力仪。本文以Sea Ⅲ型海洋重力仪在"雪龙2"号上应用为例,梳理了Sea Ⅲ型海洋重力仪工作原理、重力计算公式、结构特点和优势。对其静态试验及海上动态性能测试进行研究,通过设计重复线、交叉点来评估仪器的动态精度情况。试验表明Sea Ⅲ静态线性月漂移约为0.85×10^(-5)m·s^(2),重力仪观测值能够清晰反映当地固体潮变化特征,动态内符合精度为0.23×10^(-5)m·s^(2),均远优于海洋调查规范相关标准要求。在此基础上,结合"雪龙2"号船型、设备布置等分析总结仪器数据处理流程及仪器性能指标,为后续相关用户提供参考。

The Sea Ⅲ gravimeter is a new type of pendulum-sliding zero-length spring sea gravity-measuring instrument developed by Micro-g LaCoste manufacturer based on the principles of the LaCoste & Romberg SⅡ gravimeter. In this paper, we have done a performance test of the Sea Ⅲ gravimeter on Xuelong 2. Firstly, we gave a comprehensive introduction of its working principles, calculate formula and structural characteristics in order to describe the advantage of the Sea Ⅲ gravimeter. Then the performance of the instrument had been tested both in a static and dynamic way. Xuelong 2 has been designed to sail in a repetitive lane to evaluate its dynamical accuracy. The tests show that the static linear drift rate of the Sea Ⅲ is about 3.28 × 10^(-12) m·s^(2) while the gravimeter records present a clearly characteristic of local earth tide. The dynamic internal compliance accuracy is about 0.23 ×10^(-5) m·s^(2), which is far better than the relevant marine survey specification standards. Besides that, the type of Xuelong 2 icebreaker, its equipment layout, gravimetric data processing flow and instrumental performance evaluation are all documented in order to provide a meaningful reference for future users.