In situ characterization of dolomite crystals: Evaluation of dolomitization process and its effect on zoning

Babatunde John Olanipekun; Karem Azmy

doi:10.1111/sed.12371

journal article Jun 26, 2017

In situ characterization of dolomite crystals: Evaluation of dolomitization process and its effect on zoning

Babatunde John Olanipekun Karem Azmy

Sedimentology Vol. 64 No. 6 pp. 1708-1730 · Wiley

View at Publisher Save 10.1111/sed.12371

Abstract

AbstractDolomitization is a dissolution–re‐precipitation process which proceeds via micrometre‐scale interface reaction horizons. However, the effect of this fundamental local medium of replacement process on precipitated dolomite crystals is rarely investigated. For this purpose, dolomite samples of Ordovician Boat Harbour Formation carbonates (Newfoundland, Canada) from Main Brook and Daniel's Harbour (about 150 km apart) were studied. The investigation used high‐resolution approaches to carry out imaging and elemental analyses of individual dolomite crystals, including scanning electron microscopy, scanning electron microscopy‐based cathodoluminescence, secondary ion mass spectrometry and electron microprobe analysis. The purpose was to better understand geochemical variations across the crystal traverses and their association with dolomite replacement processes and conditions. The scanning electron microscopy‐based cathodoluminescence‐zoning character reveals three major crystal facies. Distinctly (planar boundaries) zoned core and indistinctly zoned core are zoned dolomite crystal facies in burial dolomite from Main Brook. Relatively unzoned crystal facies was identified in that of Daniel's Harbour. Compositionally zoned dolomite crystals are characterized by decreasing Sr, Na, Y and ∑REE but increasing Mn and Fe from core to rim sections. ‘Core to rim’ zoning was not found for major (Mg and Ca) elements. The zoning exhibited by the replacive dolomite crystals is interpreted to be, principally, a result of limited exchange between solutes of the bulk pore fluid and those of dissolving precursor marine carbonate. In tandem with petrographic features, the systematic compositional zoning character demonstrates that the effectiveness of the dolomitization process grades from indistinctly zoned core to relatively unzoned crystal facies via interface reaction horizons. Homogenization of major elements of core and rim sections, seen in distinctly zoned core crystal facies and to a much greater extent in relatively unzoned crystal facies, via a secondary reaction interface, is the first recognized stage of the ‘maturation process’ followed by homogenization of the trace elements seen largely in relatively unzoned crystal facies.

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References

80

[1]

10.1016/j.chemgeo.2009.11.013

[2]

10.2475/ajs.299.4.257

[3]

10.1139/e08-020

[4]

10.2113/gscpgbull.57.1.81

[5]

10.1016/j.chemgeo.2010.11.007

[6]

10.1016/j.marpetgeo.2012.10.007

[7]

Application of the trace element and isotope geochemistry of strontium to studies of carbonate diagenesis

JAY. L. BANNER

Sedimentology 10.1111/j.1365-3091.1995.tb00410.x

[8]

Calculation of simultaneous isotopic and trace element variations during water-rock interaction with applications to carbonate diagenesis

Jay L Banner, Gilbert N Hanson

Geochimica et Cosmochimica Acta 10.1016/0016-7037(90)90128-8

[9]

Banner J.L. "Rare earth element and Nd isotopic variations in regionally extensive dolomites from the Burlington‐Keokuk Formation (Mississippian): implications for REE mobility during carbonate diagenesis" J. Sed. Petrol. (1988)

[10]

10.1130/g35287.1

[11]

10.1016/s0304-4203(98)00039-5

[12]

Böttcher M.E. (2010)

[13]

Bouch J.E. (2006)

[14]

10.1016/s0012-8252(96)00051-7

[15]

10.1016/0016-7037(85)90166-8

[16]

10.2984/65.1.095

[17]

Cooper M. "Basin evolution in western Newfoundland: new insights from hydrocarbon exploration" AAPG Bull. (2001)

[18]

Curti E. (1997)

[19]

10.1016/j.oregeorev.2015.07.022

[20]

Dravis J.J. "Enhanced carbonate petrography using fluorescence microscopy" J. Sed. Petrol. (1985)

[21]

10.1016/0009-2541(90)90053-a

[22]

10.1016/0037-0738(89)90024-9

[23]

10.1016/0009-2541(72)90005-8

[24]

10.1016/j.chemgeo.2013.12.019

[25]

Gladney E.S. "Standard reference materials: compilation of elemental concentration data for NBS clinical, biological, geological, and environmental standard reference materials" Natl Bur. Stan. Spec. Publ (1987)

[26]

10.1086/626547

[27]

10.2516/ogst/2011166

[28]

10.1016/0009-2541(84)90010-x

[29]

10.1130/g36934.1

[30]

10.2110/jsr.2005.014

[31]

10.1016/j.sedgeo.2011.07.003

[32]

10.1111/sed.12119

[33]

10.1016/0016-7037(77)90238-1

[34]

Knight I. Azmy K. Boyce W.D.andLavoie D.(2008)Tremadocian carbonate rocks of the lower St. George Group Port au Port peninsula western Newfoundland: lithostratigraphic setting of diagenetic isotopic and geochemistry studies.Newfoundland and Labrador Department of Natural Resources Geological Survey Report 08–1 115–149.

[35]

10.2110/pec.80.28.0087

[36]

10.1007/bfb0009861

[37]

10.1016/0016-7037(81)90188-5

[38]

10.1016/0016-7037(84)90039-5

[39]

10.1016/0016-7037(89)90354-2

[40]

Machel H.G. "Bulk solution disequilibrium in aqueous fluids as exemplified by diagenetic carbonates" AAPG Mem. (1990)

[41]

Concepts and models of dolomitization: a critical reappraisal

Hans G. Machel

Geological Society, London, Special Publications 10.1144/gsl.sp.2004.235.01.02

[42]

Machel H.G. "Ion microprobe investigation of diagenetic carbonates and sulfides in the Devonian Nisku Formation, Alberta, Canada" SEPM Spec. Publ. (1997)

[43]

Marshall D.J. (1988)

[44]

Montañez I.P. "Late Diagenetic dolomitization of Lower Ordovician Upper Knox carbonates: a record of the hydrodynamic evolution of the Southern Appalachian Basin" AAPG (1994)

[45]

10.1016/0009-2541(90)90085-l

[46]

Morse J.W. (1990)

[47]

10.1016/0016-7037(88)90009-9

[48]

10.1016/0016-7037(94)90456-1

[49]

10.1016/s0016-7037(03)00422-8

[50]

Olanipekun B.(2016)Origin of dolomites and associated porosities in lower Ordovician Boat Harbour Formation carbonates western Newfoundland Canada. Earth Sci. Dept. Memorial University of Newfoundland St. John's. NL Canada. unpublished thesis.

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Details

Published: Jun 26, 2017
Vol/Issue: 64(6)
Pages: 1708-1730
License: View

Authors

B

Babatunde John Olanipekun

Department of Earth Sciences Memorial University of Newfoundland St. John's NL A1B 3X5 Canada

K

Karem Azmy

Department of Earth Sciences Memorial University of Newfoundland St. John's NL A1B 3X5 Canada

Funding

Petroleum Exploration Enhancement Program (PEEP) in western Newfoundland

Cite This Article

Babatunde John Olanipekun, Karem Azmy (2017). In situ characterization of dolomite crystals: Evaluation of dolomitization process and its effect on zoning. Sedimentology, 64(6), 1708-1730. https://doi.org/10.1111/sed.12371

In situ characterization of dolomite crystals: Evaluation of dolomitization process and its effect on zoning

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