File Download

There are no files associated with this item.

  Links for fulltext
     (May Require Subscription)
Supplementary

Article: Factors controlling tufa deposition in natural waters at waterfall sites

TitleFactors controlling tufa deposition in natural waters at waterfall sites
Authors
KeywordsAir-water interface
CO2 outgassing
Flow velocity
Solid-water interface
Waterfall tufa
Issue Date2004
PublisherElsevier BV. The Journal's web site is located at http://www.elsevier.com/locate/sedgeo
Citation
Sedimentary Geology, 2004, v. 166 n. 3-4, p. 353-366 How to Cite?
AbstractStudy on calcite precipitation has major implications for both the hydrochemical evolutions of river systems and the global carbon cycle. The precipitation of calcite generally requires the water to be 5-10 times supersaturated with respect to calcite, which is usually achieved by the removal of CO2. Formation of waterfall tufa has been often simply described as the result of water turbulence in fast-flowing water. In this paper, the formation mechanisms of waterfall tufa are discussed and a series of laboratory experiments are designed to simulate the hydrological conditions at waterfall sites. The influences of the air-water interface, the water flow velocity and the solid-water interface on CO2 outgassing and calcite precipitation are compared and evaluated quantitatively. The results show that the principal cause of waterfall tufa formation is the enhanced inorganic carbon dioxide outgassing resulted from the sudden hydrological changes occurring at waterfall sites, rather than organisms, evaporation or the solid-water interface. The air-water interface area and the water flow velocity are greatly increased at waterfall sites as a result of the "aeration effect", "low pressure effect" and "jet-flow effect", which greatly accelerate CO2 outgassing. Inorganic CO2 outgassing drives the waters to become highly supersaturated with respect to calcite and, consequently, results in much calcite deposition. The solid-water interface is less important as the air-water interface in affecting calcite precipitation at waterfall sites. Field measurements showed that conductivity, Ca2+ and HCO- 3 concentrations along Tianhe Creek and Hot Creek decrease downstream while pH rises. Field observations also showed that tufa deposition occurred mainly at waterfall sites. © 2004 Elsevier B.V. All rights reserved.
Persistent Identifierhttp://hdl.handle.net/10722/86199
ISSN
2015 Impact Factor: 2.236
2015 SCImago Journal Rankings: 1.513
ISI Accession Number ID
References

 

DC FieldValueLanguage
dc.contributor.authorChen, Jen_HK
dc.contributor.authorZhang, DDen_HK
dc.contributor.authorWang, Sen_HK
dc.contributor.authorXiao, Ten_HK
dc.contributor.authorHuang, Ren_HK
dc.date.accessioned2010-09-06T09:14:01Z-
dc.date.available2010-09-06T09:14:01Z-
dc.date.issued2004en_HK
dc.identifier.citationSedimentary Geology, 2004, v. 166 n. 3-4, p. 353-366en_HK
dc.identifier.issn0037-0738en_HK
dc.identifier.urihttp://hdl.handle.net/10722/86199-
dc.description.abstractStudy on calcite precipitation has major implications for both the hydrochemical evolutions of river systems and the global carbon cycle. The precipitation of calcite generally requires the water to be 5-10 times supersaturated with respect to calcite, which is usually achieved by the removal of CO2. Formation of waterfall tufa has been often simply described as the result of water turbulence in fast-flowing water. In this paper, the formation mechanisms of waterfall tufa are discussed and a series of laboratory experiments are designed to simulate the hydrological conditions at waterfall sites. The influences of the air-water interface, the water flow velocity and the solid-water interface on CO2 outgassing and calcite precipitation are compared and evaluated quantitatively. The results show that the principal cause of waterfall tufa formation is the enhanced inorganic carbon dioxide outgassing resulted from the sudden hydrological changes occurring at waterfall sites, rather than organisms, evaporation or the solid-water interface. The air-water interface area and the water flow velocity are greatly increased at waterfall sites as a result of the "aeration effect", "low pressure effect" and "jet-flow effect", which greatly accelerate CO2 outgassing. Inorganic CO2 outgassing drives the waters to become highly supersaturated with respect to calcite and, consequently, results in much calcite deposition. The solid-water interface is less important as the air-water interface in affecting calcite precipitation at waterfall sites. Field measurements showed that conductivity, Ca2+ and HCO- 3 concentrations along Tianhe Creek and Hot Creek decrease downstream while pH rises. Field observations also showed that tufa deposition occurred mainly at waterfall sites. © 2004 Elsevier B.V. All rights reserved.en_HK
dc.languageengen_HK
dc.publisherElsevier BV. The Journal's web site is located at http://www.elsevier.com/locate/sedgeoen_HK
dc.relation.ispartofSedimentary Geologyen_HK
dc.rightsSedimentary Geology. Copyright © Elsevier BV.en_HK
dc.subjectAir-water interfaceen_HK
dc.subjectCO2 outgassingen_HK
dc.subjectFlow velocityen_HK
dc.subjectSolid-water interfaceen_HK
dc.subjectWaterfall tufaen_HK
dc.titleFactors controlling tufa deposition in natural waters at waterfall sitesen_HK
dc.typeArticleen_HK
dc.identifier.openurlhttp://library.hku.hk:4550/resserv?sid=HKU:IR&issn=0037-0738&volume=166&spage=353&epage=366&date=2004&atitle=Factors+Controlling+Tufa+Deposition+in+Natural+Waters+at+Waterfall+Sitesen_HK
dc.identifier.emailZhang, DD:zhangd@hkucc.hku.hken_HK
dc.identifier.authorityZhang, DD=rp00649en_HK
dc.description.naturelink_to_subscribed_fulltext-
dc.identifier.doi10.1016/j.sedgeo.2004.02.003en_HK
dc.identifier.scopuseid_2-s2.0-2142647332en_HK
dc.identifier.hkuros90385en_HK
dc.relation.referenceshttp://www.scopus.com/mlt/select.url?eid=2-s2.0-2142647332&selection=ref&src=s&origin=recordpageen_HK
dc.identifier.volume166en_HK
dc.identifier.issue3-4en_HK
dc.identifier.spage353en_HK
dc.identifier.epage366en_HK
dc.identifier.isiWOS:000221288100009-
dc.publisher.placeNetherlandsen_HK
dc.identifier.scopusauthoridChen, J=7501884047en_HK
dc.identifier.scopusauthoridZhang, DD=9732911600en_HK
dc.identifier.scopusauthoridWang, S=49161390100en_HK
dc.identifier.scopusauthoridXiao, T=7103094085en_HK
dc.identifier.scopusauthoridHuang, R=8908186400en_HK

Export via OAI-PMH Interface in XML Formats


OR


Export to Other Non-XML Formats