广东庙湾岛风化坑的地貌特征及成因

doi:10.13284/j.cnki.rddl.002825

摘要/Abstract

摘要： 风化坑是常见的岩石坑穴地形，但容易被误解或与其他成因坑穴地形混淆。通过对庙湾岛风化坑地貌特征及形态参数进行详细测量和分析，采集风化坑内残积碎屑物、坑外岩石和当地风化壳样品进行粉晶X射线荧光光谱化学主量分析（XRF）和X射线衍射矿物分析（XRD），对风化坑发育的成因机制进行了探讨，并得出以下结论：1）风化坑的发育与地形坡度有关，通常出现在平坦裸露的岩石面上。2）风化坑的形态特征表现为宽且浅，口缘有出水口，底部平坦，侧壁最凹处与出水口高度一致，其口径发育的速度远大于深度，长轴发育速度远大于短轴。3）同一岩石面上的风化坑具有不同的大小和深度，显示了其发育程度不一，其最大、最小深度对比反映了风化坑的发育过程。4）风化坑碎屑物与表岩之间的元素迁移和化学蚀变指数（CIA值）的差异，反映了风化坑的化学风化成因。5）风化坑碎屑物的英长比大于表岩，证明了化学风化导致的矿物差异风化作用。研究表明：庙湾岛风化坑形成和发育的主要作用为坑内积水的化学风化。

关键词: 风化坑, 形态特征, 化学元素, 矿物, 庙湾岛

Abstract: Weathering pit is a common rock landscape in the East of China and there are a variety of explanations for its formation. In the thesis, the topography features and its morphological parameters of the weathering in the Miaowan Island are measured and recorded in detail. Also, the debris inside the weathering pits, parent rocks and weathering profile samples were collected. After that, they were analyzed by XRF(X Ray Fluorescence) and XRD (X-Ray Diffraction). Based on the previous factors, the topography and morphological features, chemistry and its mineral features of weathering pit were put under analysis and the genetic mechanism of the development of weathering pit is explored as well. According to the results, firstly, the development of weathering pit is not relevant to its altitude. Weathering pit of various sizes and depths might appear on any rocks that are flat and exposed at any height. Secondly, the various sizes and depths of weathering pit represent different degrees of development. Thirdly, the speed of the development of the caliber in weathering pit is higher than that of its depth. Also, the speed of the development of weathering pit’s long axis is higher than that of its short axis. There are spillways in majority of weathering pits and the groove on the wall is of the same height of the spillway. Fourthly, the element migration characteristic of the debris in the weathering pits and difference of CIA value (chemical index of alteration) between the debris and the parent rocks represent the chemical weathering cause of the weathering pit. Fifthly, the difference of the ratio of quartz to feldspar between the weathering pit’s debris and parent rocks can represent the cause for weathering pit by different weathering of minerals.

Key words: weathering pit, topography, morphology characteristics, chemical elements, mineral, the Miaowan Island

黄日辉，刘韫，王为. 广东庙湾岛风化坑的地貌特征及成因[J]. 热带地理, 2016, 36(2): 284-295.

HUANG Rihui，LIU Yun，WANG Wei. Topography，Morphological Characteristics and Formation of Weathering Pit in the Miaowan Island, Guangdong, China[J]. TROPICAL GEOGRAPHY, 2016, 36(2): 284-295.

参考文献

[1] GOUDIE A S．Weathering pits．Goudie A S．Encyclopedia of Geomorphology[M]．New York：Routledge，2004：1115-1116．

[2] TWIDALE C R，ROMANI J R V．Landforms and Geology of Granite Terrains[M]．London：Taylor & Francis，2005：207-234．

[3] MIGON P．Granite Landscapes of the World[M]．New York：Oxford University Press，2006：132-160．

[4] SMITH L L．Weather pits in granite of the southern piedmont [J]．Journal of Geomorphology，1941，4：117-127．

[5] TWIDALE C R．Weather pit（Gnamma）[J]．Australian Geographer，1965，9（5）：318-319．

[6] HALL A M，PHILLIPS W M．Weathering pit as indicators of the relative age of granite surface in the Cairngorm Mountains，Scotland [J]．Geografiska Annaler：Series A，Physical Geography，2006，88（2）：135-150．

[7] VILLAR D D，ARTEAGA C，GIMéNEZ R G，SMITH E A，PEDRAZA J．Diurnal and seasonal water variations of temperature，pH，redox potential and conductivity in gnammas (weathering pits)：Implications for chemical weathering[J]．Catena，2008，2（1）：37-48．

[8] 韩同林．发现冰臼[M]．北京：华夏出版社，2004．

[9] 韩同林，劳雄，郭克毅．关于南国冰臼群成因的商榷[J]．热带地理，2000，20（1）：72-80．

[10] 吕洪波，任晓辉，杨超．赤峰等地第四纪大陆冰川的地貌证据[J]．地质论评，2006，52（3）：379-385．

[11] 赵志中，钱方，何培元，凌小惠，李名则，孙继民，郝治，田明中．内蒙古克什克腾旗花岗岩石林的发现及成因[J]．地质论评，2007，53（增刊）：98-103．

[12] KUSKY T，GUO L，XIANG S，GUO X，XU X．A critical examination of evidence for a Quaternary glaciation in Mt. Laoshan，Eastern China [J]．Journal of Asian Earth Sciences，2011，40（1）：403-416．

[13] 杨超群．冰臼与壶穴之争述评[J]．热带地理，2001，21（1）：86-93．

[14] 朱照宇．广东揭西河谷地貌与风化层特征初步观察[J]．热带地理，2000，20（4）：331-336．

[15] 曾昭璇，黄进，黄玉昆，刘尚仁，李春初，杨超群，黄金龙，刘会平，唐晓春，朱照宇，徐起浩，陈定国，李平日，陈华堂，黄镇国．关于“‘冰臼’与‘壶穴’”之争专家笔谈[J]．热带地理，2001，21（3）：282-289．

[16] 王为，周尚哲，李炳元，解波，冯小珍．崂山冰臼之质疑[J]．第四纪研究，2011，31（5）：917-932．

[17] 朱诚，崔之久，李中轩．浙江缙云县大洋山石鼓尖花岗岩坑穴成因[J]．地理学报，2008，63（7）：735-743．

[18] 章雨旭．“冰臼”成因争鸣——以克什克腾旗青山岩臼群为例[J]．地质论评，2005，51（6）：680-712．

[19] 施雅风．韩同林的“冰臼论”是对花岗岩类岩石“负球状风化”的误解[J]．地质论评，2010，56（3）：349-354．

[20] 王为，许刘兵，林志海，刘志鹏，段茹萍，陈科景，黄日辉，刘韫，赖宜讯．海岸壶穴与风化坑的成因差异及证据——以广东沙扒镇和庙湾岛海岸为例[J]．第四纪研究，2013，33（5）：1016-1033．

[21] 黄玉昆，夏法，陈国能，杨明钦．珠江口外岛屿的若干地质地貌特征[J]．海洋通报，1985，4（1）：46-51．

[22] VILLAR D D．Early formation of gnammas（weathering pits）in a recently glaciated area of Torresdel Paine，southern Patagonia（Chile）[J]．Geomorphology，2006，76（1/2）：137-147．

[23] LI X，QI C，LIU Y，LIANG X，TU X，XIE L．Petrogenesis of the Neoproterozoic bimodal volcanic rocks along the western margin of the Yangtze Block：new constraints from Hf isotopes and Fe/Mn ratios [J]．Chinese Science Bulletin，2005，50（21）：2481-2486．

[24] NESBITT H W，YOUNG G M．Early Proterozoic climates and plate motions inferred from major element chemistry of lutites[J]．Nature，1982，299（5885）：715-717．

[25] MCLENNAN S M．Weathering and global denudation[J]．The Journal of Geology，1993，101（2）：295-303．

[26] EYNATTEN H V，BARCELó-Vidal C，PAWLOWSKY-Glahn V．Modelling compositional change：the example of chemical weathering of granitoid rocks[J]．Mathematical Geology，2003，35（3）：231-251．

[27] NESBITT H W．Mobility and fractionation of rare earth elements during weathering of a granodiorite[J]．Nature，1979，279：206-210．

[28] YUSOFF Z M，NGWENYA B T，PARSONS I．Mobility and fractionation of REEs during deep weathering of geochemically contrasting granites in a tropical setting，Malaysia[J]．Chemical Geology，2013，349：71-86．

[29] 黄镇国，张伟强，陈俊鸿，刘瑞华．中国南方红色风化壳[M]．北京：海洋出版社，1996：38-57，127-134．

[30] 王为，林志海，刘志鹏，黄日辉，刘韫，赖宜讯．福建长乐屏山风化坑与河流壶穴的成因及其证据[J]．地理学报，2013，68（3）：328-342．

[31] 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）：1523-1534．

[32] LUTGENS F K，TARBUCK E J．Essentials of geology [M]．6th ed.．New Jersey，US：Prentice Hall，1998：450．

[33] 王为，周尚哲，李炳元，林志海，刘志鹏，黄日辉，赖宜讯，陈科景．崂山山顶风化坑化学风化过程的岩石化学与矿物学证据[J]．第四纪研究，2012，32（1）：158-166．

[34] ZEDEF V，KOCAKB K，DOYEN A，OZSEN H，KEKEC B．Effect of salt crystallization on stones of historical buildings and monuments，Konya，Central Turkey[J]．Building and Environment，2007，42（3）：1453-1457．

[35] DUZGOREN-Aydin N S，AYDIN A，MALPAS J．Re-assessment of chemical weathering indices：Case study on pyroclastic rocks of Hong Kong[J]．Engineering Geology，2002，63（1/2）：99-119．

[36] NG W W C，GUAN P，SHAN Y J．Weathering mechanisms and indices of the igneous rock of Hong Kong[J]．Quarterly Journal of Engineering Geology and Hydrogeology，2001，34（2）：133-151．

[37] GOLDICH S S．A study in rock-weathering[J]．The Journal of Geology，1938，46（1）：17-58．

[38] 彭云辉，陈浩如，李少芬．珠江河口水体的pH和碱度[J]．热带海洋，1991，10（4）：49-55．

[39] MOTTERSHEAD D N，PYE K．Tafoni on coastal slopes，South Devon，UK[J]．Earth Surface Processes and Landforms，1994，19（6）：543-563．

[40] MUSTOE G E．The origin of honeycomb weathering[J]．Geological Society of America Bulletin，1982，93（2）：108-115．

[41] WILSON M．Chemical weathering of some primary rock-forming minerals[J]．Soil Science，1975，119（5）：349-355．

[42] 朱筱敏．沉积岩石学[M]．北京：石油工业出版社，2008：133-134．

[43] CAMPBELL E M．Granite landforms[J]．Journal of the Royal Society of Western Australia，1997，80（3）：101-112．