【摘要】 为了评估地球磁异常(EMAG2)数据中海域资料的质量问题,选择Kolbeinsey脊南段地区约193 500 km2的1∶500 000及1∶1 000 000的航磁数据进行对比分析。基于地球磁异常(EMAG2)数据,利用解析延拓方法获得了EMAG2(向下延拓4 km)及航磁异常(向上延拓4 km)。利用相关分析法对EMAG2与航磁异常(向上延拓4 km)、EMAG2(向下延拓4 km)与航磁异常进行相关分析,得到了相应的相关系数。通过对这些数据之间相关系数及差值特征的综合分析,评估了EMAG2数据中Kolbeinsey脊南段地区磁力数据的质量。研究结果表明,EMAG2数据融合了大量海域航空磁测及海洋磁测资料,在测线较密的海域,其数据质量相对较高。然而若将4 km高度的EMAG2数据换算到海平面高度的异常数据,其数据质量较低。更多还原

【Abstract】 In order to evaluate the quality of the offshore magnetic data in the Earth Magnetic Anomaly Grid(2-arc-minute resolution)(EMAG2),the authors chose the aeromagnetic data at 1∶500 000 and 1∶1 000 000 scales of the southern section of the Kolbeinsey Ridge with a total area of 193 500 km2 to compare and analyze.Based on the EMAG2 data,the authors obtained the EMAG2(downward continuation 4 km) and the aeromagnetic anomaly(upward continuation 4 km)using the analytical continuation method.Then,the correlation coefficients between the aeromagnetic anomaly(upward continuation 4 km) and the EMAG2,and the aeromagnetic anomaly and the EMAG2(downward continuation 4 km)were calculated by the correlation analysis method.Finally,through comprehensive analysis of the features of these correlation coefficients and differences,the quality of the magnetic data of the southern section of the Kolbeinsey Ridge was evaluated in the database EMAG2.The results showed that the EMAG2 integrated a large number of the airborne or offshore magnetic data.The quality of the offshore magnetic data is relatively high in the offshore areas with dense lines.However,the quality of the offshore magnetic data is relatively low if the EMAG2 data at 4 km altitude is converted to the anomaly data at sea level.更多还原