含油气球冠模型三维重力归一化总梯度场特征  

CHARACTERISTICS OF THE THREE-DIMENSIONAL NORMALIZED FULL GRADIENT FIELD OF GRAVITY ANOMALY IN THE OIL SPHERE CORONAL MODEL

作　　者：高丽坤[1] 蒋甫玉[2,3] 张凤旭[4] 李颜贵[5] 孟令顺[4] 

机构地区：[1]内生金属矿床成矿机制研究国家重点实验室南京大学地球科学与工程学院,江苏南京210093 [2]河海大学地球科学与工程系,江苏南京210098 [3]河海大学岩土工程科学研究所,江苏南京210098 [4]吉林大学地球探测科学与技术学院,吉林长春130026 [5]中国地质科学院地球物理地球化学勘察研究所,河北廊坊065000

出　　处：《物探与化探》2010年第2期214-220,共7页Geophysical and Geochemical Exploration

基　　金：河海大学博士后基金资助项目(2016/408107);河海大学引进人才科研启动基金资助项目(2084/40801136)

摘　　要：重力归一化总梯度的三维计算中,将圆滑滤波因子分别引入向下延拓和导数换算响应因子中,推导了其计算公式及数值实现过程,同时给出了具体的计算步骤;对含油气球冠模型的三维归一化总梯度场特征进行了分析与研究。研究结果表明,对于含油气球冠模型来说,不同于均匀球冠模型在各个深度的切平面等值线图中表现出单峰异常的特征,其三维归一化总梯度场的特征表现为:无论在过中心剖面的等值线图还是在某个深度的切片图中,只有当截止频率取值适当时才可以表现出"两高夹一低"的典型储油气藏标志特征,若取值不当,其表现出来的特征与均匀球冠模型相似。此外,归一化总梯度场等值线图中出现"两高夹一低"的位置,往往是含油气球冠所在位置和深度。This paper introduces filter factors respectively in downward continuation and derivative calculation for calculating the threedimensional normalized full gradient field of gravity anomaly. The authors deduced the computing formula and the process for achieving its numerical value, and then gave the specific calculation procedure. Characteristics of 3D normalized full gradient of gravity anomaly in the homogeneous oil sphere coronal model were analyzed. It is concluded that, for oil sphere coronal, the 3D normalized full gradient field has the following features： no matter whether it is in a figure of central section or in that of a slice, only when the suitable cut-off frequency is obtained can the ＂two folders and one low＂ of typical characteristic signs of oil-gas reservoir be shown; otherwise, it is similar to the model of homogeneous sphere coronal which shows characteristics of a single peak anomaly. In addition, the position of ＂ two folders and one low＂ in the contour map of normalized full gradient field is usually the position and depth of the oil sphere coronal.

关 键 词：含油气球冠 组合滤波 三维重力归一化总梯度 等值线图 

分 类 号：P631.1[天文地球—地质矿产勘探]