DOLOMITIZATION OF PLEISTOCENE SEDIMENTS ON HAINAN ISLAND, CHINA

Wang Guozhong; Lu Bingquan; Quan Songqing

Article Contents

Article Navigation > Acta Sedimentologica Sinica > 1984 > 2(4): 97-110

Wang Guozhong, Lu Bingquan, Quan Songqing. DOLOMITIZATION OF PLEISTOCENE SEDIMENTS ON HAINAN ISLAND, CHINA[J]. Acta Sedimentologica Sinica, 1984, 2(4): 97-110.

Citation:

Wang Guozhong, Lu Bingquan, Quan Songqing. DOLOMITIZATION OF PLEISTOCENE SEDIMENTS ON HAINAN ISLAND, CHINA[J]. Acta Sedimentologica Sinica, 1984, 2(4): 97-110.

DOLOMITIZATION OF PLEISTOCENE SEDIMENTS ON HAINAN ISLAND, CHINA

Research Institute of Marine Geology, Tongji University Shanghai

Received Date: 1983-04-07
Publish Date: 1984-12-10

Abstract

The Pleistocene dolomites occurred in the abrasion flat and coast of the inter-tidal zone of the fringing rear reef in Paipu area，Zuan County,Hainan Island，Chi-na. The abrasion flat is made of sediments of the littoral-river sandy-conglome-ratic facies, including abundant mould of marine mollusca. On the flat the sea cliff consists of littoral lagoonal mudy siltfine sand facies. Dolomites(dolostone)consist of dolomite and clastic grains. It is confirmed by the identifications of thin section, staining techniques, thermocouple analysis，X-ray- diffraction techniques，scanning electron microscopy. electron probe microanaly-sis, chemical quantitative analysis etc. There are two kinds of dolomites: 1) dolomite of euhedral rhombic crystal witii tonal tenure; 2) clear, limpid dolomite formed by fissure filling and shell moalding. The origin of dolomites is of replacement in the early diagenesis stage, Thereare three patterns of occureaces of dolomites: 1) Dolomitic sandy conglomerateformed by- coarse clas'tic deposits and dolomite has a bedding structure, 40-50cm inthickness, and consists of gravels, several cm to 30cm in major diameter and do-lomite, having the forms of matrix and cement, It has been known now as the coar-sest elastic materials associated with dolomite, 2) Sandy dolomite of lenticular orbedding structure 8-30cm, in thickness，interlayers with elastic depositss it consi-sts of 75% dolomite and about 20-25% elastic materiels and authigenic minerals, 3)Dolomite crystals and dolomitized infiltration tubules distribute in muddy sand-siltbed. The latter has circle and oval cross section and concentric stratoid structure.The loose and rough central area and outer stratum consist of 10-40% dolomite.The fine inner stratum dolomitized intensely consists of 900u dolomite and only 5%elastic materials and 5% pore space. The silts- elastic particles have relict structure,caused by replacement (Plat. I, 3，II，5-7，Table 4) Thcre arc three kinds of dolomitiza tion, which may be sure in this region: 1. Dolomitization of the miring of fresh ground water and sea water in inter-tidal zone of coast and in the mouth of small river. These conditions favour thereplacement of dolomite because of the drastical dropping of salinity and the Mg/Caratio remaining less variance. 2. Dolomitization of schizahaline pore- water in the intertidal zone .It forms clear, limpid dolomite, replacing shell of mollusca and filling the tension crack with a lamellar arrangement. 3, Dolomitization of plants forms dolomitized in(il'tralion tubule, It is di-rectly- controlled by the physiological action of plants around their roots. In the in-tertidal zone of the coast, because the transpiration and respiration of plants elec-tip-ely suck up moisture and cationes and drain off the C02 and organic acid, thesalinity and Mg Ca ratio become higher and higher,and the microenvironment nearthe root becomes favourable of the replacement, Thus，the dissolution，precipitationand metasomatism of carbonate take place and dolomitized infiltration tubules areformed around the root system, This local intense dolomitization forces the peo-ple to realize the possibility of forming dolomite(dolostone) by replacing elastic rocks on gig en conditions

References

[1]

(1)王国忠、吕炳全、全松青，1982,海南岛更新世白云羚的发现及其形成环垅分析，同济大学学报，4期，P .18-26。

(2)中国科学院南海海洋研究所地质研究宝，1978，华南沿海第四纪地质，科学出版社。

(3)杜恒俭、陈华慧、曹伯勋，1981，地貌学及第四纪地质学，地质出版社。

(4)北京农业大学编，1961,植物生理学(上、下)农业出版社。

(5)冯增昭，1979，白云岩的生成机理与成因分类，天然气勘探与开发，2期，P. 1一9。

(6)Folk。R. L.and Ward, W. C.，1975, Brazos river bar: A study in the sig-nification of grain size parameters, J. Sediment. Petrol. 27, p. 3-27.

(7)Warne, S.，1963, The Nature and Significance of Microscopic Mineral Matter in Some New South Wales Coals. Thesis, L,niv,New S. Wales, Sydney，N, S.W. 306 pp. Unpublished.

(8)Friedmaa，G. M. 1978, Staining Techniques, in Fairbridge, R. W. and Bour-geois, J. ed. The Encyclopedia of Sedimentology，Dowden，Hutchison and Ross,Inc, p. 764-765.

(9)Joint Commitee on Powder Diffraction Standards: Po+-der Diffraction File Set1-22(ASTM-J-JCPDS)。

(10)Chilingar, G. V'.，1957, Classification of Limestones and Dolomites on Basis of Ca/Mg Ratio. J. Sediment, Petrol.V.27. 187-189,

(11)Bathurst, R, G. C.，1971，Carbonate Sediments and their Diagenesis, Elsevier Publishing Company Amsterdam London Mew fork。

(12)Milliman, J, D, 1974, Marine Carbonates. Springar-Verlag Berlin. Heidelberg. New York.

(13)Friedman, G. M, and Sanders, J, E, 1967, Origin and Occurrence of dolomite， In: Chilingar, G. V.，et al.(Editors)，Carbonate Rocks,( Developments in Sedimentology，9A)Elsevier Publishing Company Amsterdam London New York.

(14) F olk，R, L. and Land, L, S.，1975, Mg/Ca ratio and Salinity;two Controls over Crystallization of Dolomite. Am. Assoc, Petroleum Geologists Bull, Vol. 59, p. 62-68,

(15) Liebermann, O., 1967, Synthesis of Dolomite, Nature 213: p. 241-245,

(16) Badiozamani，K,，1973, The Dolomitization Model-Application to the Middle Ordovician of Vdisconsin, J, Sediment. Petrol. Vol. 43, No, 4, p. 965-984.

(17)Hsu, K .J. and Siegenthaler, C.，1969, Preliminary experiments on hydrody- namic movement induced dy evaporation and their bearing on the dolomite problem, Sedimentology，12;11-25.

Proportional views

通讯作者: 陈斌, bchen63@163.com

1.
沈阳化工大学材料科学与工程学院沈阳 110142

Get Citation

PDF

XML

Article Metrics

Article views(552) PDF downloads(508) Cited by()

Proportional views

DOLOMITIZATION OF PLEISTOCENE SEDIMENTS ON HAINAN ISLAND, CHINA

Research Institute of Marine Geology, Tongji University Shanghai

Received Date: 1983-04-07

Publish Date: 1984-12-10

Abstract: The Pleistocene dolomites occurred in the abrasion flat and coast of the inter-tidal zone of the fringing rear reef in Paipu area，Zuan County,Hainan Island，Chi-na. The abrasion flat is made of sediments of the littoral-river sandy-conglome-ratic facies, including abundant mould of marine mollusca. On the flat the sea cliff consists of littoral lagoonal mudy siltfine sand facies. Dolomites(dolostone)consist of dolomite and clastic grains. It is confirmed by the identifications of thin section, staining techniques, thermocouple analysis，X-ray- diffraction techniques，scanning electron microscopy. electron probe microanaly-sis, chemical quantitative analysis etc. There are two kinds of dolomites: 1) dolomite of euhedral rhombic crystal witii tonal tenure; 2) clear, limpid dolomite formed by fissure filling and shell moalding. The origin of dolomites is of replacement in the early diagenesis stage, Thereare three patterns of occureaces of dolomites: 1) Dolomitic sandy conglomerateformed by- coarse clas'tic deposits and dolomite has a bedding structure, 40-50cm inthickness, and consists of gravels, several cm to 30cm in major diameter and do-lomite, having the forms of matrix and cement, It has been known now as the coar-sest elastic materials associated with dolomite, 2) Sandy dolomite of lenticular orbedding structure 8-30cm, in thickness，interlayers with elastic depositss it consi-sts of 75% dolomite and about 20-25% elastic materiels and authigenic minerals, 3)Dolomite crystals and dolomitized infiltration tubules distribute in muddy sand-siltbed. The latter has circle and oval cross section and concentric stratoid structure.The loose and rough central area and outer stratum consist of 10-40% dolomite.The fine inner stratum dolomitized intensely consists of 900u dolomite and only 5%elastic materials and 5% pore space. The silts- elastic particles have relict structure,caused by replacement (Plat. I, 3，II，5-7，Table 4) Thcre arc three kinds of dolomitiza tion, which may be sure in this region: 1. Dolomitization of the miring of fresh ground water and sea water in inter-tidal zone of coast and in the mouth of small river. These conditions favour thereplacement of dolomite because of the drastical dropping of salinity and the Mg/Caratio remaining less variance. 2. Dolomitization of schizahaline pore- water in the intertidal zone .It forms clear, limpid dolomite, replacing shell of mollusca and filling the tension crack with a lamellar arrangement. 3, Dolomitization of plants forms dolomitized in(il'tralion tubule, It is di-rectly- controlled by the physiological action of plants around their roots. In the in-tertidal zone of the coast, because the transpiration and respiration of plants elec-tip-ely suck up moisture and cationes and drain off the C02 and organic acid, thesalinity and Mg Ca ratio become higher and higher,and the microenvironment nearthe root becomes favourable of the replacement, Thus，the dissolution，precipitationand metasomatism of carbonate take place and dolomitized infiltration tubules areformed around the root system, This local intense dolomitization forces the peo-ple to realize the possibility of forming dolomite(dolostone) by replacing elastic rocks on gig en conditions

HTML

Reference (1)

[1]

DOLOMITIZATION OF PLEISTOCENE SEDIMENTS ON HAINAN ISLAND, CHINA

Abstract

References

Proportional views

通讯作者: 陈斌, bchen63@163.com

Article Metrics

Proportional views

Related