摘要
本文介绍了AMT(音频大地电磁测深)法在雅库特和俄罗斯的Archangelsk金刚石矿区勘探中的应用.文章描述了金伯利岩岩脉的位置和形状、电性参数、围岩和上覆岩层特性.金伯利岩矿区位于易于被AMT方法确定的参考导电层之上,或者在高阻层之上.金伯利岩岩脉发育在金伯利岩矿区良导的局部边缘地区.这些良导区与地堑构造有关,其边界与基底和厚层沉积覆盖的弯曲褶皱相一致,并具有强破裂和利于金伯利岩岩浆渗透的特点.依据AMT数据,可很好地确定局部良导区,并作为最有远景的矿脉发育区.利用AMT数据可确定断裂带和区分矿区的构造断层.金伯利岩控制的断层一般被圈闭的岩墙充填,易于被磁法资料确定,而金伯利岩的围岩断层不包含圈闭的岩墙,由磁法难以测量,因此就可较好地确定金伯利岩.本文给出了由沉积层覆盖的简单地质条件下发现岩脉的例子,也介绍了包含几种不同类型金伯利岩如导电的斑状金伯利岩、并被圈闭和厚层沉积覆盖的复杂地质条件下确定岩脉的实例.
Results of works by the audiomagnetotelluric sounding method in the Yakut and Archangelsk diamond provinces are considered in this paper. Features of kimberlite pipes localization and shape, electric properties of kimberlites, host and overlying rocks are described. Examples of locating kimberlite fields and clusters, and also discovering pipes in easy (with sedimentary cover) and in difficult (overlain by traps) geological conditions are presented.
出处
《地球物理学报》
SCIE
EI
CAS
CSCD
北大核心
2010年第3期657-676,共20页
Chinese Journal of Geophysics
关键词
音频大地电磁测深
金刚石勘探
金伯利岩矿区
岩脉
金伯利岩岩脉
Audiomagnetotelluric sounding, Diamond exploration, Kimberlite field, Pipe cluster, Kimberlite pipe