南图瓦卢礁群区重力资料的初步分析

1976年3月至1978年10月,国家海洋局“向阳红05”号海洋调查船(14,000吨)对太平洋中部海域先后进行了四次远洋综合科学调查,为研究该海域的自然环境提供了大量的地质-地球物理、水文、气象、生物、化学资料,并在南纬11°41'.2,西经178°20'.5处新发现了一个水深仅32米的珊瑚礁滩——“向阳礁”.四次远洋调查共完成的重力、水深测线总长为57,492公里.

PRELIMINARY ANALYSIS OF GRAVITY DATA ON THE SOUTH TUVALU REEF GROUP AREA

From March 1976 to October 1978,comprehensive scientific investigations to the Central Pacific region were carried out four times by the R/V Xadngyanghong No.5.The total profiling line for the gravity and water depth is 57,492 km long.A beach of coral reef..(32 m deep) is found at 11°41'2S,178°20.'5W.The first two cruises have been made in the South Tuvalu reef group area,covering the range within 10°-14°S and 177° 4'E-177°W.Various kinds of reliefs are concentrated in this area,with the northeast portion belonging to the Central Pacific Basin,northwest segment to Melanesim.Basin and the south section being part of the Fiji tableland.In the middle of this area there is a typical coral island reef group,which is the product of gradual sinking of submarine volcanic cluster under tropical oceanic condition.In the area studied,the average water depth is 2,829 m,the maximum depth is 4,828m,and the mean slop is about 5°.