Geochemistry of subsurface Late Quaternary ironstones in Rajshahi and Bogra Districts, Bangladesh: implications for genetic and depositional conditions

详细信息    查看全文 | 推荐本文 |

英文篇名：Geochemistry of subsurface Late Quaternary ironstones in Rajshahi and Bogra Districts, Bangladesh: implications for genetic and depositional conditions 作者：Md.Sazzadur ; Rahman ; Ismail ; Hossain ; Pradip ; Kumar ; Biswas ; Md.Abdur ; Rahim ; A.S.M.Mehedi ; Hasan ; Md.Ibrahim ; Adham 英文作者：Md.Sazzadur Rahman;Ismail Hossain;Pradip Kumar Biswas;Md.Abdur Rahim;A.S.M.Mehedi Hasan;Md.Ibrahim Adham;Department of Geology and Mining, University of Rajshahi;Institutes of Mining, Mineralogy and Metallurgy (IMMM),BCSIR;Department of Disaster Resilience and Engineering,Patuakhali Science and Technology University; 英文关键词：Ironstone;;Geochemistry;;Goethite;;Siderite;;Bangladesh 中文刊名：Acta Geochimica 英文刊名：地球化学学报(英文版) 机构：Department of Geology and Mining, University of Rajshahi;Institutes of Mining, Mineralogy and Metallurgy (IMMM),BCSIR;Department of Disaster Resilience and Engineering,Patuakhali Science and Technology University; 出版日期：2019-05-17 出版单位：Acta Geochimica 年：2019 期：03 语种：英文; 页：80-89 页数：10 CN：52-1161/P ISSN：2096-0956 分类号：P618.31

摘要

The present study deals with the geochemistry of Late Quaternary ironstones in the subsurface in Rajshahi and Bogra districts, Bangladesh with the lithological study of the boreholes sediments. Major lithofacies of the studied boreholes are clay, silty clay, sandy clay, fine to coarse grained sand, gravels and sands with(fragmentary) ironstones. The ironstones contain major oxides, Fe_2 O_3*(*total Fe)(avg. 66.6 wt%), SiO_2(avg. 15.3 wt%), Al_2 O_3(avg. 4.0 wt%), MnO(avg. 7.7 wt%), and CaO(avg. 3.4 wt%). These geochemical data imply that the higher percentage of Fe_2 O_3* along with Al_2 O_3 and MnO indicate the ironstone as goethite and siderite, which is also validated by XRD data. A comparatively higher percentage of SiO_2 indicates the presence of relative amounts of clastic quartz and manganese-rich silicate or clay in these rocks. These ironstones also have significant amounts of MnO(avg. 7.7 wt%) suggesting their depositional environments under oxygenated condition. Chemical data of these ironstones suggest that the source rock suffered deep chemical weathering and iron was mostly carried in association with the clay fraction and organic matter. Iron concretion was mostly formed by bacterial build up in swamps and marshes, and was subsequently embedded in clayey mud.Within the coastal environments, the water table fluctuates and goethite and siderite with mud and quartz became dry and compacted to form ironstone.
        The present study deals with the geochemistry of Late Quaternary ironstones in the subsurface in Rajshahi and Bogra districts, Bangladesh with the lithological study of the boreholes sediments. Major lithofacies of the studied boreholes are clay, silty clay, sandy clay, fine to coarse grained sand, gravels and sands with(fragmentary) ironstones. The ironstones contain major oxides, Fe_2 O_3*(*total Fe)(avg. 66.6 wt%), SiO_2(avg. 15.3 wt%), Al_2 O_3(avg. 4.0 wt%), MnO(avg. 7.7 wt%), and CaO(avg. 3.4 wt%). These geochemical data imply that the higher percentage of Fe_2 O_3* along with Al_2 O_3 and MnO indicate the ironstone as goethite and siderite, which is also validated by XRD data. A comparatively higher percentage of SiO_2 indicates the presence of relative amounts of clastic quartz and manganese-rich silicate or clay in these rocks. These ironstones also have significant amounts of MnO(avg. 7.7 wt%) suggesting their depositional environments under oxygenated condition. Chemical data of these ironstones suggest that the source rock suffered deep chemical weathering and iron was mostly carried in association with the clay fraction and organic matter. Iron concretion was mostly formed by bacterial build up in swamps and marshes, and was subsequently embedded in clayey mud.Within the coastal environments, the water table fluctuates and goethite and siderite with mud and quartz became dry and compacted to form ironstone.

引文

Al-Bassam KS,Tamar-Agha MY(1998)Genesis of the Hussainiyat ironstone deposit,Western Desert,Iraq.Miner Depos33:266-282
    Armstrong FA(2008)Why did nature choose manganese to make oxygen?Philos Trans R Soc B 363:1263-1270.https://doi.org/10.1098/rstb.2007.2223
    Aubert H,Pinta M(1977)Trace elements in soils(developments of soil science 7).Elsevier,Amsterdam
    Bellanca A,Claps M,Erba E,Masetti D,Neri R,Premoli-Silva I,Venezia F(1996)Orbitally induced limestone/marlstone rhythms in the Albian-Cenomanian Cismon section(Venetian regio′n,northern Italy):sedimentology,calcareous and siliceous plankton distribution,elemental and isotope geochemistry.Palaeogeogr Palaeoclimatol Palaeoecol 126:227-260
    Calvert SE,Pedersen TF(1996)Sedimentary geochemistry of manganese:implications for the environment of formation of manganiferous black shales.Econ Geol 91:36-47
    Curray JR(1991)Geological history of the Bengal geosynclines.J Assoc Explor Geophys 12:209-219
    Curtis CD,Pearson MJ,Somogy VA(1975)Mineralogy,chemistry,and origin of a concretionary siderite sheet(clay-ironstone band)in the Westphalian of Yorkshire.Miner Mag 40:385-393
    Dill HG,Techmer A(2009)The geogene and anthropogenetic impact on the formation of per descensum vivianite-goethite-siderite mineralization in Mesozoic and Cenozoic siliciclastic sediments in SE Germany.Sediment Geol 217:95-111
    Ferdousy MF(2011)Paleoenvironments of Bengal Basin during Holocene as interpreted from geophysical and biogeochemical studies:[Dissertation]M.Phil.thesis,Department of Geology and Mining,University of Rajshahi,Bangladesh
    Goodbred SL Jr,Kuehl SA(2000)The significance of large sediment supply,active tectonism,and eustasy on margin sequence development:Late Quaternary stratigraphy and evolution of the Ganges-Brahmaputra delta.Sediment Geol 133:227-248
    Goto A,Tatsumi Y(1994)Quantitative analysis of rock samples by an X-ray fluorescence spectrometer(I).Rigaku J P11:40-59
    Goto A,Tatsumi Y(1996)Quantitative analysis of rock samples by an X-ray fluorescence spectrometer(II).Rigaku J P13:20-38
    Hossain I,Tsunogae T,Rajesh HM,Chen B,Arakawa Y(2007)Palaeoproterozoic U-Pb SHRIMP zircon age from basement rocks in Bangladesh:a possible remnant of Columbia supercontinent.C R Geosci 339:979-986
    Hossain I,Roy KK,Pradip KB,Alam M,Moniruzzaman M,Deeba F(2014)Geochemical characteristics of Holocene sediments from Chuadanga district,Bangladesh:implication for weathering,climate,redox condition,provenance and tectonic setting.Chin JGeochem 33:336-350
    Hossain I,Tsunogae T,Tsutsumi Y,Takahashi K(2018)Petrology,geochemistry and LA-ICP-MS U-Pb geochronology of Paleoproterozoic basement rocks in Bangladesh:an evaluation of calcalkaline magmatism and implication for Columbia supercontinent amalgamation.J Asian Earth Sci 157:22-39
    Islam MS(2001)Stratigraphy and Sedimentology of Gondwana Rocks in the Barapukuria Basin,Dinajpur District,Bangladesh.Unpublished Ph.D.Thesis,Jahangirnagar University,Dhaka,Bangladesh
    Islam MS,Hossain I(2006)Lithofacies and first-order embedded markov chain analyses of the Gondwana sequence in the boreholes GDH-40 and GDH-43,Barapukuria coalfield,Bangladesh.Bangladesh J Geol 25:64-80
    James HL(1996)Chemistry of iron rich sedimentary rocks.Data of geochemistry,6th edition,pp w1-w26
    Johnson JE,Webb SM,Ma C,Fischer WW(2016)Manganese mineralogy and diagenesis in the sedimentary rock record.Geochim Cosmochim Acta 173:210-231
    J?rgensen BB,Nelson DC(2004)Sulfide oxidation in marine sediments:Geochemistry meets microbiology,In:Amend JP,Edwards KJ,Lyons TW,(eds),Sulfur biogeochemistry-past and present.Geological Society of America Special Paper379:63-81
    Krauskopf KB(1979)Introduction to geochemistry.McGraw-Hills,Tokyo,p 617
    Lal D,Schopf JW,Abbott PL,Vacher L,Jull AJT,McHargue L(2010)Nuclear,chemical and biological characterization of formation histories of ironstones from several sites in Southern California:dominant role of bacterial activity.Earth Planet Sci Lett 296:227-234
    Maynard JB(2010)The chemistry of manganese ores through time:a signal of increasing diversity of earth-surface environments.Econ Geol 105:535-552
    Mohanta MK(2007)Geochemistry of iron ores.In:Proceeding of iron ore.Chapter 5,Jamshedpur,pp.44-57
    Najman Y,Bickle M,BouDagher-Fadel M,Carter A,Garzanti E,Paul M,Wijbrans J,Willett E,Oliver G,Parrish R,Akhter SH,Allen R,Ando S,Chisty E,Reisberg L,Vezzoli G(2008)The paleogene record of Himalayan erosion:Bengal Basin,Bangladesh.Earth Planet Sci Lett 273:1-14
    Pettijohn FJ(1984)Sedimentary rocks,3rd edn.Harper and Raw Publisher,USA
    Ponten A,Plink-Bjo¨rklund P(2007)Depositional environments in an extensive tide-influenced delta plain,Middle Devonian Gauja Formation,Devonian Baltic Basin.Sedimentology 54:969-1006
    Poulton SW,Krom MD,Raiswell R(2004)A revised scheme for the reactivity of iron(oxyhydr)oxide minerals towards dissolved sulfide.Geochim Cosmochim Acta 68:3703-3715
    Rahman MA,Alam MS,Islam MA(2004)Lithostratigraphy and alluviation history of the quaternary deposits in Panchagarh district,north-western part of Bangladesh.Bangladesh Geosci J10:13-24
    Rangin C(2017)Active and recent tectonics of the Burma Platelet in Myanmar(Chapter 3).In:Barber AJ,Khin Zaw and Crow MJ(eds)Myanmar:geology,resources and tectonics.Geological Society,London,Memoirs vol 48,53-64
    Raymo ME,Ruddiman WF(1992)Tectonic forcing of Late Cenozoic climate.Nature 359:117-122
    Reimann KU(1993)Geology of Bangladesh.Gebruder Borntraeger Verlags,Science Publishers,160 p
    Roy S(1968)Mineralogy of the different genetic types of manganese deposits.Econ Geol 63:760-786
    Salama W,Aref M,Gaupp R(2014)Facies analysis and palaeoclimatic significance of ironstones formed during the Eocene greenhouse.Sedimentology 61:1594-1624
    Steckler MS,Mondal DR,Akhter SH,Seeber L,Feng L,Gale J,Hill EM,Howe M(2016)Locked and loading megathrust linked to active subduction beneath the Indo-Burman Ranges.Nat Geosci9:615-619
    Tobia FH,Kettanaha YA,Mustafa MM(2014)Petrography and geochemistry of Ga’ara sedimentary ironstones,Western Desert of Iraq.J Afr Earth Sci 97:261-272
    Uddin A,Lundberg N(2004)Miocene sedimentation and subsidence during continent-continent collision,Bengal Basin,Bangladesh.Sedim Geol 164:131-146
    Worden RH(1996)Controls on halogen concentrations in sedimentary formation waters.Mineral Mag 60:259-274
    Young TP(1989)Phanerozoic ironstones:an introduction and review.In:Young TP,Taylor WEG(eds),Phanerozoic ironstones.Geol Soc Spec Publ No.46,pp ix-xxv
    Zaher MA,Rahman A(1980)Prospects and investigations for mineral in the northwestern parts of Bangladesh.In:Petroleum and mineral resources of Bangladesh,Seminar and Exhibition,8-12 October 1980,Dhaka,9-18