The Discontinuity of Rockmass Chemical Weathering and Its Scientific Significance
Received date: 2006-01-13
Revised date: 2006-05-15
Online published: 2006-07-15
Chemical weathering is highly discontinuous and the discontinuity exists at the macro-scale, meso-scale and micro-scale.Macro-fractures are the main places of chemical weathering occurring. In weathering rockmass fresh rock blocks are surrounded and separated by corrosion zones. Water-rock reaction in Meso-fractures and pores between mineral particles determine the discontinuity of chemical weathering at the meso-scale. Mineral dissolution occurs preferentially in crystal defects and is discontinuous at the micro-scale. Because of discontinuity, chemical weathering can add water-rock interface and raise mineral dissolution rate. By way of spreading existing damages and accumulating weathering residue, discontinuous chemical weathering has the efficiency of separating, cracking rockmass, rock blocks and forming minerals, which may cause the rockmass mainly made up of fresh rock breaking away from the parent rock on a large scale. Chemical weathering affects rock blocks piling up the slope foot and brings them to split smaller rock and mineral debris that can be carried way by surface runoff. So, chemical weathering can promote remarkably slope planation landform evolution course.
Xu Zemin,Huang Runqiu,Tang Zhengguang,Fei Weishui . The Discontinuity of Rockmass Chemical Weathering and Its Scientific Significance[J]. Advances in Earth Science, 2006 , 21(7) : 706 -712 . DOI: 10.11867/j.issn.1001-8166.2006.07.0706
[1] Wilson M J. Chemical weathering of some primary rock-forming minerals[J]. Soil Science, 1975, 1 199(5): 349-355.
[2] Nesbitt H W, Young G M. Prediction of some weathering trends of plutonic and volcanic rocks based on thermodynamic and kinetic considerations[J]. Geochimica et Cosmochimica Acta,1984,48(7):1 523-1 534.
[3] Drever J I. The effect of land plants on weathering rates of silicate minerals[J]. Geochimica et Cosmochimica Acta,1994,58(10):2 325-2 332.
[4] Chigira M, Nakamoto M, Nakata E. Weathering mechanisms and their effects on the landsliding of ignimbrite subject to vapor-phase crystallization in the Shirakawa pyroclastic flow, northern Japan[J]. Engineering Geology,2002, 66(1/2): 111-125.
[5] Li Jingying, Zhang Jing. Chemical weathering processes and atmospheric CO2 consumption in the yellow river drainage basin[J]. Marine Geology & Quaternary Geology, 2003, 23(2): 43-49.[李晶莹,张经. 黄河流域化学风化作用与大气CO2的消耗[J].海洋地质与第四纪地质, 2003, 23(2): 43-49.]
[6] Holdren G R J R, Speyer P M. pH dependent changes in the rates and stoichiometry of dissolution of an alkali feldspar at room temperature[J]. American Journal of Science,1985, 285(10): 994-1 026.
[7] Velbel M A. Influence of temperature and mineral surface characteristics on feldspar weathering in natural and artificial systems: A first approximation[J]. Water Resourie Research,1990,26(12): 3 049-3 054.
[8] Wogelius R A, Walther J V. Olivine dissolution at 25℃: Effects of pH, CO2 and organic acids[J]. Geochimica et Cosmochimica Acta,1991,55(4):943-954.
[9] Casey W H, Sposito G. On the temperature dependence of mineral dissolution rates[J]. Geochimica et Cosmochimica Acta,1992, 56(10):3 825-3 830.
[10] Harrison W J, Thyne G D. Prediction of diagenetic reactions in the presence of organic acids[J]. Geochimica et Cosmochimica Acta,1992, 56(2): 565-586.
[11] Brady P V, Carroll S A. Direct effects of CO2 and temperature on silicate weathering: Possible implications for climate control[J]. Geochimica et Cosmochimica Acta,1994,58(8):1 853-1 856.
[12] Xu Zemin, Huang Runqiu, Tang Zhengguang. Kinetics of silicate mineral dissolution and implications for landslide studies[J]. Chinese Journal of Rock Mechanics and Engineering,2005, 24(9):1 479-1 491.[徐则民, 黄润秋, 唐正光. 硅酸盐矿物溶解动力学及其对滑坡研究的意义[J]. 岩石力学与工程学报, 2005, 24(9):1 479-1 491.]
[13] Jing L. A review of techniques, advances and outstanding issues in numerical modeling for rock mechanics and rock engineering[J]. In ternational Journal of Rock Mechanics & Mining Sciences, 2003, 40(3): 283-353.
[14] Cai Meifeng, He Manchao, Liu Dongyan. Rock Mechanics and Engineering[M]. Beijing: Science Press, 2002: 453.[蔡美峰,何满潮,刘东燕. 岩石力学与工程[M].北京: 科学出版社, 2002: 453.]
[15] Xu Zemin, Huang Runqiu, Tang Zhengguang, et al. Clay minerals and failure of slopes[J]. Chinese Journal of Rock Mechanics and Engineering, 2005, 24(5): 729-740.[徐则民, 黄润秋, 唐正光, 等. 粘土矿物与斜坡失稳[J].岩石力学与工程学报, 2005, 24(5):729-740.]
[16] LaFleur R G. Geomorphic aspects of groundwater flow[J]. Hydrogeology Journal,1999,7(1): 78-93.
[17] Velbel M A. Geochemical mass balances and weathering rates in forested watersheds of the southern Blue Ridge[J]. American Journal of Science,1985,285(10): 904-930.
[18] Sun Qinghe, He Xi, Li Changlu. The effects of microfractures for development the lowest permeability reservior in water injection[J]. Acta Petrolet Sinica, 2000, 21(4): 52-57.[孙庆和, 何玺, 李长禄.特低渗透储层微缝特征及对注水开发效果得影响[J]. 石油学报,2000, 21(4): 52-57.]
[19] Su Jian. A study on reservoir characteristics of Yanhewan region[J]. Dishentou Youqitian, 2002, 7(1): 13-15.[苏坚. 沿河湾地区浅油层储层特征研究[J].低渗透油气田,2002,7(1):13-15.]
[20] Xiao Luchuan, Zhen Li, Zheng Yan. Non-darcy seepage flow characteristic in ultra-low permeable reservoirs[J]. Petroleum Geology & Oilfield Development in Daqing, 2000,19(5): 27-28, 30.[肖鲁川,甄力,郑岩.特低渗透储层非达西渗流特征研究[J].大庆石油地质与开发, 2000,19(5): 27-28, 30.]
[21] Zhang Li, Yang Yajuan, Yue Leping, et al. Characteristics of micro-fractures and their influence on waterflooding in aershan reservoir,Hanan oilfield[J]. Oil ＆ Gas Geology, 2001, 22(2): 158-160,193.[张莉, 杨亚娟, 岳乐平,等. 哈南阿尔善油藏微裂缝特征及其对开发的影响[J].石油与天然气地质, 2001, 22(2): 158-160, 193.]
[22] Tian Kaiming. Low permeable media in hydrogeology[J]. Hydrogeology and Engineering Geology, 2000, (2): 27-28.[田开铭.开展对低渗透介质的水文地质学研究[J].水文地质工程地质, 2000, (2): 27-28.]
[23] Schott J, Berner R A, Sjoberg E L. Mechanism of pyroxene and amphibole weathering.Ⅰ. Experimental studies of iron-free minerals[J]. Geochimica et Cosmochimica Acta,1981,45(11):2 123-2 135.
[24] Banfield J F, Barker W W. Direct observation of reactant-product interfaces formed in natural weathering of exsolved defective amphibole to smectite: Evidence for episodic, isovolumetric reaction involving structural inheritance[J]. Geochimica et Cosmochimica Acta,1994, 58(5): 1 419-1 429.
[25] Holdren G R J R, Speyer P M. Reaction-rate surface area relationships for an alkali feldspar during the early stages of weathering,Ⅰ. Initial observations[J]. Geochimica et Cosmochimica Acta,1985,49(3): 675-681.
[26] Holdren G R J R, Speyer P M. Reaction-rate surface area relationships during the early stages of weathering.Ⅱ. Date on eight additional feldspars[J]. Geochimica et Cosmochimica Acta,1987, 51(9):2 311-2 318.
[27] Liu Xiangwen, Chen Jiawei, Bao Zhengyu. The relation between dissolution kinetics of some minerals and crystal defects[J]. Journal of Chinese Electron Microscopy Society,2002, 21(5): 751-752.[刘祥文, 陈家玮, 鲍征宇. 几种矿物溶解热动力学与晶体缺陷的关系[J].电子显微学报,2002,21(5): 751-752.]
[28] Anbeek C. Surface roughness of minerals and implications for dissolution studies[J]. Geochimica et Cosmochimica Acta,1992, 56(4):1 461-1 469.
[29] Helgeson H C, Murphy W M, Aagaard P. Thermodynamic and kinetic constraints on reaction rates among minerals and aqueous solutions.Ⅱ. Rate constant, effective surface area, and the hydrolysis of feldspar[J]. Geochimica et Cosmochimica Acta,1984, 48(12):2 405-2 432.
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