测绘学报
測繪學報
측회학보
Acta Geodaetica et Cartographica Sinica
2015年
10期
1092-1099
,共8页
欧阳明达%孙中苗%翟振和%刘晓刚
歐暘明達%孫中苗%翟振和%劉曉剛
구양명체%손중묘%적진화%류효강
重力地形导纳%海底地形%重力异常%均衡理论
重力地形導納%海底地形%重力異常%均衡理論
중력지형도납%해저지형%중력이상%균형이론
gravity topography admittance%bathymetry%gravity anomalies%isostatic theory
系统探讨了采用重力异常的导纳理论推估海底地形的方法。在频率域内对海底地形和重力异常的相关性进行了分析,确定在20~300 km波段内两者相关系数最高,适合通过重力异常反演。以皇帝海山链为例,分别采用未补偿导纳模型和顾及挠曲补偿的导纳模型开展研究,其中涉及的地壳厚度和有效弹性厚度等参数通过均衡响应函数法得到。引入余弦低通滤波器,有效地解决了向下延拓过程中产生的高频震荡问题。算例结果表明,采用重力异常的导纳理论能够有效地反演海底地形,结果真实可靠,反演模型的相对精度在6%左右,与ET OPO1模型相当,且能够刻画出ET OPO1模型中未显现的地形细节。由于地形变化剧烈,反演模型在海山链沿线附近精度不甚理想。
繫統探討瞭採用重力異常的導納理論推估海底地形的方法。在頻率域內對海底地形和重力異常的相關性進行瞭分析,確定在20~300 km波段內兩者相關繫數最高,適閤通過重力異常反縯。以皇帝海山鏈為例,分彆採用未補償導納模型和顧及撓麯補償的導納模型開展研究,其中涉及的地殼厚度和有效彈性厚度等參數通過均衡響應函數法得到。引入餘絃低通濾波器,有效地解決瞭嚮下延拓過程中產生的高頻震盪問題。算例結果錶明,採用重力異常的導納理論能夠有效地反縯海底地形,結果真實可靠,反縯模型的相對精度在6%左右,與ET OPO1模型相噹,且能夠刻畫齣ET OPO1模型中未顯現的地形細節。由于地形變化劇烈,反縯模型在海山鏈沿線附近精度不甚理想。
계통탐토료채용중력이상적도납이론추고해저지형적방법。재빈솔역내대해저지형화중력이상적상관성진행료분석,학정재20~300 km파단내량자상관계수최고,괄합통과중력이상반연。이황제해산련위례,분별채용미보상도납모형화고급뇨곡보상적도납모형개전연구,기중섭급적지각후도화유효탄성후도등삼수통과균형향응함수법득도。인입여현저통려파기,유효지해결료향하연탁과정중산생적고빈진탕문제。산례결과표명,채용중력이상적도납이론능구유효지반연해저지형,결과진실가고,반연모형적상대정도재6%좌우,여ET OPO1모형상당,차능구각화출ET OPO1모형중미현현적지형세절。유우지형변화극렬,반연모형재해산련연선부근정도불심이상。
Based on the admittance theory of gravity anomalies ,the method of bathymetry prediction was studied in detail in this paper .In frequency domains ,the correlation between gravity anomalies and bathymetry was analyzed ,which suggests that the wavelength band correlated strongly was in a range of 20—300 km,this band was appropriated to inverse bathymetry by gravity anomalies .Took the Emperor Chain as an example ,the uncompensated admittance model and flexural isostatic admittance model were used for researching ,respectively ,the included parameter of crust thickness and effective el astic thickness were calculated by the isostatic response function .As the down continuation factor was unstable ,a high‐cut filter was proposed in the inversion procedure to ensure convergence of series .The results showed that , the admittance theory of gravity anomalies can be used effectively in the bathymetry prediction , the predicted result was real and reliable ,the relative precision was approximately 6% ,which was equal to ETOPO1 model ,and the detailed feature of sea floor which was not showed in ETOPO1 model can also be depicted;the precisions were not so well in areas of ocean mountains intensively distributed because of the complexionoftheseafloor.