鲁西齐河地区岩(矿)石物性特征及应用

Physical Characteristics of Rocks and Ores and Their Application in Qihe Area,Western Shandong

为系统掌握鲁西齐河地区岩(矿)石物性特征,服务于基础地质和矿产资源调查,在该地区及周边实地采集了磁性、密度等物性参数,并根据不同岩(矿)石分类进行统计分析。结果表明,磁铁矿的磁性最大,基性侵入岩的磁性大于中酸性侵入岩,而沉积岩的磁性最弱。新生界与下伏地层和岩体的密度差异明显,其界面起伏变化可以引起明显的重力异常。磁铁矿的密度最大,黄铁矿次之。太古界泰山岩群变质岩密度较大,也可引起一定强度的重力异常。通过物性特征与地球物理场之间的联系,综合其他资料进行了岩性填图,圈定变质岩和侵入岩范围,确定了强磁性地质体范围作为找矿靶区,并基于物性特征进行了重磁联合反演,推断矿体的埋深、厚度等信息,与钻探验证结果吻合。研究结果提高了对该地区岩(矿)石物性特征的认识程度,为地球物理资料的反演解释和地质构造、矿产研究等提供更可靠的依据。

In order to understand the physical characteristics of rocks and ores in Qihe,western Shandong and serve to basic geology and mineral resources investigation,the magnetic and density properties were collected in the survey area and the surrounding area,and statistics and analysis were given on the physical properties in terms of different kinds of rocks and ores. The result is that magnetite has the maximum value of magnetic property,the values of magnetic properties of basic rocks are bigger than the intermediate-acidic intrusive rocks,and the values of magnetic properties of sedimentary rocks are the smallest. The density of the Cenozoic strata is obviously different from formations and intrusive rocks under the covered area. Their interfaces cause the obvious gravity anomalies. The density value of magnetite is the biggest,and the density value of iron pyrite is the second biggest. The density of the metamorphic rocks of the Archeozoic Taishan rock group can cause certain gravity anomaly. Taking advantage of the relationship between the physical characteristics and the geophysical field,this paper mapped the lithology synthesizing other data,determined the ranges of metamorphic rocks and intrusive rocks,and delimited the ranges of ferromagnetic geological bodies as the target prospecting areas. Based on the physical characteristics,the depth and thickness information about the magnetite ore was inferred by conducting gravity and magnetic joint inversion. The result was nearly the same as the result of the verification borehole. The work of the research has promoted the understanding of physical characteristics of rocks and ores in this area,and provided more reliable basis for geophysical inversion and interpretation,geological structure and mineral resources research.