The effect of soaking or not on the density determination of rock and ore
ZHANG Bai-Fan1(), XIAO Feng1, LI Yi-Ke2,3, KE Chang-Hui2,3
1. College of Geo-Exploration Science and Technology, Jilin University, Changchun 130026, China 2. Institute of Mineral Resources, Chinese Academy of Geological Sciences, Beijing 100037, China 3. MNR Key Laboratory of Metallogeny and Mineral Assessment, Beijing 100037, China
Rock density determination is an important method to obtain accurate density values, and it is also an indispensable parameter for topographic correction and middle layer correction of gravity measurement results. The higher the accuracy of density measurement, the higher the accuracy of geological interpretation. However, there are different opinions on whether soaking treatment is needed before the determination of rock density in different versions of measurement specification. In this paper, we taking 12 kinds of rock (ore) specimens in Bayan Obo mining area as an example, comparing the density changes before and after soaking. It is concluded that the density of rock increases in varying degrees after soaking, except mica-type iron ore. For rocks (ores) with developed pores or fissures, the percentage of density difference after soaking is greater than 0.5%, and the density difference percentage will be greater than 0.5%. However, for the rock (ore) with dense structure, the influence of soaking on the density measurement is less than 2 times of the measurement error, which is negligible.
张百帆, 肖锋, 李以科, 柯昌辉. 浸泡与否对岩矿石密度测定的影响[J]. 物探与化探, 2021, 45(1): 173-177.
ZHANG Bai-Fan, XIAO Feng, LI Yi-Ke, KE Chang-Hui. The effect of soaking or not on the density determination of rock and ore. Geophysical and Geochemical Exploration, 2021, 45(1): 173-177.
Jiao X H, Wu Y G. Gravity and magnetic exploration[M]. Beijing: Geological Publishing House, 2009.
[2]
Hinze W J, Aiken C, Brozena J, et al. New standards for reducing gravity data:the north American gravity database[J]. Geophysics, 2005,70(4):J25-J32.
doi: 10.1190/1.1988183
[3]
Blakely R J. Potential theory in gravity and magnetic application[M]. Cambridge: Cambridge University Press, 1996.
[4]
Hinze W J, Von F R B, Saad A H. Gravity and magnetic exploration[M]. Cambridge: Cambridge University Press, 2012.
Pu J Z, Zhang X L. A method for choosing correction density value in gravity measurement in mountain area[J]. Geophysical and Geochemical Exploration, 1993,17(6):471-474.
[6]
Oldenburg D W. The inversion and interpretation of gravity anomaly[J]. Geophysics, 1974,39(4):526-536.
doi: 10.1190/1.1440444
Guo Y Z, Guo X W, Li L, et al. The density characteristics of rocks from Xiarihamu copper nickel sulfide deposit and problem of gravity exploration deployment in east Kunlun,Qinghai province[J]. Chinese Journal of Engineering Geophysics, 2016,13(1):1-6.
Luo F B, Zhang B, Min G, et al. The physical properties study of the northern section of Longmenshan tectonic belt[J]. Computing Techniques for Geophysical and Geochemical Exploration, 2016,38(2):191-197.
Yun M H, Gao J, He Y L, et al. Relations of velocity and density with porosity,clay content and water saturation in reservoirs[J]. Progress in Exploration Geophysics, 2004,27(2):104-107.
[15]
雍世和, 洪有密. 测井资料综合解释与数字处理[M]. 北京: 石油工业出版社, 1982.
[15]
Yong S H, Hong Y M. Comprehensive interpretation and digital processing of logging data[M]. Beijing: Petroleum Industry Press, 1982.
