Hostname: page-component-78c5997874-dh8gc Total loading time: 0 Render date: 2024-11-08T21:33:19.887Z Has data issue: false hasContentIssue false
  • English
  • Français

Alteration of Ilmenite in the Cretaceous Sandstones of Nova Scotia, Southeastern Canada

Published online by Cambridge University Press:  01 January 2024

Georgia Pe-Piper ,
David J. W. Piper  and
Lila Dolansky
Georgia Pe-Piper*
Affiliation:
Department of Geology, Saint Mary’s University, Halifax, N.S., Canada B3H 3C3
David J. W. Piper
Affiliation:
Geological Survey of Canada (Atlantic), Bedford Institute of Oceanography, PO Box 1006, Dartmouth, N.S., Canada B2Y 4A2
Lila Dolansky
Affiliation:
Department of Geology, Saint Mary’s University, Halifax, N.S., Canada B3H 3C3
*
*E-mail address of corresponding author: [email protected]
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Most detrital ilmenite grains in sandstones of the Chaswood Formation are completely altered to pseudorutile, leucoxene and rutile. The textural, chemical and mineralogical changes involved in alteration were tracked using electron microprobe analyses, backscattered electron images, and elemental maps. Ilmenite grains (Ti/(Ti+Fe) ≈ 0.48) alter patchily to pseudorutile (Ti/(Ti+Fe) 0.5–0.7) with volume loss, forming a porous structure and this process continues with the development of leucoxene (Ti/(Ti+Fe) 0.7–0.9). Within the pseudorutile and leucoxene, stubby prismatic rutile crystals have been precipitated. Si and A1 occur in the altered ilmenite, either (1) inherited from original quartz and muscovite inclusions in the parent crystal or (2) as kaolinite altered from muscovite inclusions or precipitated in the pore space, under pedogenic or early diagenetic conditions. Distribution of alteration phases has been related to facies and diagenetic variations. With increasing amounts of leaching in different types of paleosols, there was increasing alteration of pseudorutile to leucoxene. In light gray mudstones and interbedded sandstones with diagenetic kaolinite that formed beneath the water table from percolating meteoric water, most leucoxene was converted to rutile. Burial diagenesis (to vitrinite reflectance values >0.4%) also promoted the change from leucoxene to rutile. The alteration of ilmenite is an important source of Fe for diagenetic minerals in the Chaswood Formation and correlative offshore deltaic and marine facies of the Scotian basin.

Keywords

AlterationDiagenesisIlmenitePseudorutileRutile
Type
Research Article
Information
Clays and Clay Minerals , Volume 53 , Issue 5 , October 2005 , pp. 490 - 510
Copyright
Copyright © The Clay Minerals Society 2005

References

Anand, R.R. and Gilkes, R.J., (1984) Weathering of ilmenite in a lateritic pallid zone Clays and Clay Minerals 32 363–374 10.1346/CCMN.1984.0320504.CrossRefGoogle Scholar
Basu, A. and Molinaroli, E., (1989) Provenance characteristics of detrital opaque Fe-Ti oxide minerals Journal of Sedimentary Petrology 59 922–934.Google Scholar
Basu, A. Molinaroli, E., Morton, A.C. Todd, S.P. and Flaughton, P.D.W., (1991) Reliability and application of detrital opaque Fe-Ti oxide minerals in provenance determination Developments in Sedimentary Provenance Studies London Geological Society 55–65.Google Scholar
Davies, E.H. Akande, S.O. and Zentilli, M., (1984) Early Cretaceous deposits in the Gays River lead-zinc mine Current Research, part A, Geological Survey of Canada Paper 84-1A 353–358.Google Scholar
Drummond, K.J. and Flalhouty, M T, (1992) Geology of Venture, a geopressured gas field, offshore Nova Scotia Giant Oil and Gas Fields of the Decade 1978—1988 Oklahoma American Association of Petroleum Geologists, Tulsa 55–71.Google Scholar
Falcon-Lang, H. Fensome, R.A. and Venugopal, D.V., (2003) The Cretaceous age of the Vinegar Hill silica deposit of southern New Brunswick: evidence from palynology and paleobotany Atlantic Geology 39 39–46.CrossRefGoogle Scholar
Force, E.R. (1991) Geology of titanium-mineral deposits. Geological Society of America Special Paper, 259, 112 p.Google Scholar
Frost, M.T. Grey, I.E. Flarrowfield, I.R. and Mason, K., (1983) The dependence of alumina and silica contents on the extent of alteration of weathered ilmenites from western Australia Mineralogical Magazine 47 201–208 10.1180/minmag.1983.047.343.10.CrossRefGoogle Scholar
Gobeil, J.-P., (2002) Stratigraphy, sedimentology, and provenance of the Chaswood Formation, West Indian Road pit, Shuhenacadie, Nova Scotia Canada Dalhousie University.Google Scholar
Grey, I.E. and Reid, A.F., (1975) The structure of pseudorutile and its role in the natural alteration of ilmenite American Mineralogist 60 898–906.Google Scholar
Grist, A.M. and Zentilli, M., (2003) Post-Paleocene cooling in the southern Canadian Atlantic region: evidence from apatite fission track models Canadian Journal of Earth Sciences 40 1279–1297 10.1139/e03-045.CrossRefGoogle Scholar
Hacquehard, P.A., (1984) Composition, rank and depth of burial of two Nova Scotia lignite deposits Geological Survey of Canada Paper 84-1A 11–15.Google Scholar
Haggerty, S., (1976) Opaque mineral oxides in terrestrial igneous rocks Mineralogical Society of America Short Course Notes 3 Hg1–Hg75.Google Scholar
Kretz, R., (1983) Symbols for rock-forming minerals American Mineralogist 68 277–279.Google Scholar
Pe-Piper, G. Stea, R.R. Ingram, S. and Piper, D.J.W., (2004) Heavy minerals and sedimentary petrology of the Cretaceous sands from the Shubenacadie outlier, Nova Scotia Nova Scotia Department of Natural Resources, Open File Report .Google Scholar
Pe-Piper, G., Dolansky, L. and Piper, D.J.W. (2005a) Petrography of the mid-Cretaceous Chaswood Formation in borehole RR-97-23, Elmsvale Basin, Nova Scotia: sedimentary environment, detrital mineralogy and diagenesis. Geological Survey of Canada Open File Report, 4837, 231 pp.Google Scholar
Pe-Piper, G., Piper, D.J.W., Hundert, T. and Stea, R.R. (2005b) Outliers of Lower Cretaceous Chaswood Formation in northern Nova Scotia: results of scientific drilling and studies of sedimentology and sedimentary petrography. Geological Survey of Canada Open File Report, 4845, 305 pp.Google Scholar
Pe-Piper, G. Dolansky, L. and Piper, D.J.W., (2005) Sedimentary environment and diagenesis of the Lower Cretaceous Chaswood Formation, southeastern Canada: the origin of kaolin-rich mudstones Sedimentary Geology 178 75–97 10.1016/j.sedgeo.2005.04.002.CrossRefGoogle Scholar
Piper, D.J.W. Pe-Piper, G. and Douglas, E.V., (2005) Tectonic deformation and its sedimentary consequences during deposition of the Lower Cretaceous Chaswood Formation, Elmsvale basin, Nova Scotia Bulletin of Canadian Petroleum Geology 53 189–199 10.2113/53.2.189.CrossRefGoogle Scholar
Schroeder, P.A. and Shiflet, J., (2000) Ti-bearing phases in the Huber Formation, an east Georgia kaolin deposit Clays and Clay Minerals 48 151–158 10.1346/CCMN.2000.0480201.CrossRefGoogle Scholar
Schroeder, P.A. LeGolvan, J.J. and Roden, M.F., (2002) Weathering of ilmenite from granite and chlorite schist in the Georgia Piedmont American Mineralogist 87 1616–1625 10.2138/am-2002-11-1211.CrossRefGoogle Scholar
Schroeder, P.A. Pruett, R.J. and Melear, N.D., (2004) Crystal-chemical changes in an oxidative weathering front in a middle Georgia kaolin deposit Clays and Clay Minerals 52 212–220 10.1346/CCMN.2004.0520207.CrossRefGoogle Scholar
Stea, R.R. and Pullan, S., (2001) Hidden Cretaceous basins in Nova Scotia Canadian Journal of Earth Sciences 38 1335–1354 10.1139/e01-023.CrossRefGoogle Scholar
Stea, R.R., Finck, P.W., Pullan, S.E. and Corey, M.C. (1996) Cretaceous deposits of kaolin clay and silica sand in the Shubenacadie and Musquodoboit valleys, Nova Scotia, Canada. N.S. Department of Natural Resources, Mines and Minerals Branch, Open File Report 960003, 58 pp.Google Scholar
Temple, A.K., (1966) Alteration of ilmenite Economic Geology 61 695–714 10.2113/gsecongeo.61.4.695.CrossRefGoogle Scholar
Teufer, G. and Temple, A.K., (1966) Pseudorutile — a new mineral intermediate between ilmenite and rutile in the natural alteration of ilmenite Nature 211 179–181 10.1038/211179b0.CrossRefGoogle Scholar