海洋能源勘探开发、海洋环境监测、地质灾害防治和大洋热液喷口调查等热点海洋科学问题中，对海洋底水中原位甲烷浓度数据的高精度获取及分布变化规律研究是关键。我国在海洋底水原位甲烷探测器研制方面与国外产品还有相当的差距，关键技术等方面还受制于人。本申请拟在原有良好的研发基础上对以下关键科学问题进行攻关：水下长期连续测试中，海水环境对敏感探头物理性能的影响及变化规律；无标准气体校准长期测量过程中，残余累积气体和测试方式对甲烷本底的影响及变化规律；海洋底水综合测试条件下实测数据结果的地球化学特征及校正方法。本项目的实施将从传感器结构设计、敏感材料配方、关键节点参数和测试方式设置等方面，建立“海洋底水原位溶解气甲烷指标高精度监测技术”的科学方法和改进方案，实现海水中原位溶解甲烷浓度数据的连续、实时采集和数据校正，为海洋能源勘探开发、海洋环境监测、全球气候变化与碳循环等科学问题研究提供技术支撑。

For the hot marine scientific researching of the marine energy resources' prospecting and exploiting, marine environmental monitoring, geological disaster prevention and marine hydrothermal vents investigation, the key is the high precision acquisition and distribution change investigations of in-situ methane concentration data in marine bottom water. We still have a considerable gap in marine bottom water for in-situ methane detectors, and many key technical aspects are also put us in a restricted position. Based on our good original results, this application aim at solving the key scientific problems: the influence and the variation of seawater environment on the physical properties of gas sensors under water with the long-term continuous testing; the influence and the variation of the residual gases and the test mode on the base of methane in the long-term measurement of non standard gas calibration; the geochemical characteristics and the correction methods of the measured data in the comprehensive test of marine bottom water. The implementation of this project will establish the scientific methods and improvements of the high precision monitoring technology for in-situ dissolved methane index in marine bottom water from the design of detector structure, the sensitive material formula, the key node parameters and the test mode setting, etc. It will realize the continuous, real-time collection and correction of the in-situ methane concentration data in the seawater, and provide technical supports for prospecting and exploiting of marine gas hydrate resources and marine environmental monitoring.