High-Resolution Marine Gravity, Seafloor Topography, and Seafloor Roughness

pi将通过重新跟踪ERS-1和Geosat高度计的波形来提高海洋重力和地形的精度和分辨率，从而更好地成像局部重力异常，以便：1)解析深海底的精细构造结构（如深海山、微板块、传播裂缝、海山、陨石撞击等）；2)在全球范围内测量海底粗糙度谱，以更好地约束潮汐耗散、垂直混合和海洋中尺度环流模式；3)解析大陆边缘精细尺度重力场，为基础研究和油气勘探提供依据。这里资助的工作将使全球重力模型得到2倍的改进。在缺少地理卫星数据的近岸地区，这种改善将更为显著。资助的任务包括：a.重新跟踪ERS-1高度计的波形，将噪声降低2倍；b.重新跟踪Geosat高度计的波形，使噪声降低20%；c.结合来自Geosat、ERS、GFO、Topex和Jason-I的高度计数据，以CHAMP和GRACE的长波场（~400 km）为约束，开发新的海洋重力模型；D.基于现有最佳重力和地形数据构建新的全球地形模型；E.进行小尺度构造、海底粗糙度和地壳均衡的科学研究。

The PIs will improve the precision and resolution of marine gravity and topography by re-tracking the waveforms of the ERS-1 and Geosat altimeters to better image local gravity anomalies for: 1) resolving the fine-scale tectonic structure of the deep ocean floor (e.g., abyssal hills, microplates, propagating rifts, seamounts, meteorite impacts, . . .); 2) measuring the roughness spectra of the seafloor on a global basis to better constrain models of tidal dissipation, vertical mixing, and mesoscale circulation of the oceans; and 3) resolving the fine-scale gravity field of the continental margins for basic research and petroleum exploration. The work funded here will make a factor of 2 improvement in the global gravity models. The improvement will be more significant in near-shore areas where Geosat data are missing. Funded tasks include: a. re-track the waveforms of ERS-1 altimeter to reduce the noise by a factor of 2; b. re-track the waveforms of the Geosat altimeter to reduce the noise by 20%; c. combine altimeter data from Geosat, ERS, GFO, Topex, and Jason-I to develop new marine gravity models using long-wavelength fields ( ~400 km) from CHAMP and GRACE as constraints; d. construct a new global topography model based on the best available gravity and topography data; e. perform scientific investigations of small-scale tectonics, seafloor roughness, and isostasy.