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Diagenesis of Clay Minerals from Lower Cretaceous Shales of North Eastern British Columbia

Published online by Cambridge University Press:  01 July 2024

A. E. Foscolos  and
H. Kodama
A. E. Foscolos
Affiliation:
Institute of Sedimentary and Petroleum Geology, 3303 33 Street, Calgary, Alberta, Canada
H. Kodama
Affiliation:
Soil Research Institute, Department of Agriculture, Ottawa, Ontario, Canada
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Abstract

Clay minerals from shale outcrops of the Lower Cretaceous Buckinghorse Formation (4250 ft thick) were investigated in order to assess their degree of diagenesis and their oil-generating potential. Crystallinity index, sharpness ratio, per cent of illite which is the 2M polymorph and presence of discrete minerals have been studied in the whole clay fraction, while the very fine clay fraction has been subjected to X-ray diffraction, differential thermal, thermogravimetric, differential thermogravimetric, i.r. spectroscopy, surface area and chemical analyses. With information derived from these studies and from published data, a classification scheme was devised which relates variation of clay mineralogy to diagenetic stages and burial depth.

Data on the < 2 μm size fraction show that the crystallinity index decreases while the sharpness ratio and per cent of illite which is the 2M polymorph increase with burial depth. Results on the <0·08 μm fraction reveal that a three-component interstratified clay mineral exists. In addition, Fourier transform calculations and chemical and physicochemical analyses indicate that both the ratio of the amounts of non-hydrated clays (illite) to hydrated clays and the K2O content of clays increase with burial depth; cation exchange capacity and surface area decrease with burial depth.

Based upon a classification scheme, which was devised by combining criteria and data derived from the studies of Weaver (1961a), Kubier (1966), Burst (1969) and Dunoyer de Seconzac (1970), the upper and middle parts of the formation (upper 3250 ft) fall within the middle stage of diagenesis whereas the lower part (1000 ft) is allocated to the beginning of late diagenesis. In terms of Burst’s (1969) work, the upper 3250 ft are transitional between the stability and dehydration zones indicating that, prior to uplift, hydrocarbons may have been in the process of migration. The lower 10000 ft of the formation are in the restricted dehydration zone, indicating that hydrocarbon migration should have been completed.

Résumé

Résumé

Des minéraux argileux provenant d’affleurements de schistes de la Formation Buckinghorse du Crétacé inférieur (4250 pieds d’épaisseur) ont été étudiés en vue de déterminer leur degré de diagénèse et leur potential de réservoir de pétrole. L’indice de cristallinité, le rapport de finesse des pics, le pourcentage d’illite qui est le polymorphe 2M et la présence de minéraux discrets ont été étudiés sur la fraction argileuse totale, tandis que la fraction argileuse très fine a été étudiée par la diffraction X, les analyses thermique différentielle, thermogravimétrique, thermogravimétrique dérivée, la spectroscopie infrarouge, la mesure de surface spécifique et les analyses chimiques. A l’aide des informations tirées de ces études et de résultats déjà publiés, un schéma de classification a été établi qui relie les variations de la minéralogie d l’argile aux étapes de la diagénèse et à la profondeur d’enfouissement.

Les résultats obtenus avec la fraction <2 μm montrent que l’indice de cristallinité diminue tandis que la rapport de finesse des pics et le pourcentage d’illite qui est le polymorphe 2M augmentent avec la profondeur d’enfouissement. Les résultats obtenus avec la fraction <0,08 μm rélèvent l’existence d’un minéral argileux interstratifié à trois composants. En plus, les calculs de transformées de Fourier et les analyses chimiques et physicochimiques indiquent que le rapport des teneurs en argiles non hydratées (illite) à celles des argiles hydratées, et que la teneur en K2O des argiles augmentent simultanément avec la profondeur; la capacité d’échange de cations et la surface spécifique diminuent avec la profondeur.

Si l’on se fonde sur un schéma de classification qui a été établi en combinant les critères et les résultats tirés des travaux de Weaver (1961a), Kubier (1966). Burst (1969) et Dunoyer de Segonzac (1970), les zones supérieures et moyennes de la formation (3250 pieds d’épaisseur) coïncident avec l’étape moyenne de la diagénèse, tandis que la zone inférieure (1000 pieds) est attribuée au début de la dernière diagénèse. Selon les termes du travail de Burst (1969), les 3250 pieds supérieurs sont une transition entre les zones de stabilité et de déshydratation, indiquant que, avant la remontée, les hydrocarbures peuvent avoir participé au processus de migration. Les 1000 pieds inférieurs de la formation sont dans une zone de déshydratation restreinte, indiquant que la migration des hydrocarbures doit avoir été achevé.

Kurzreferat

Kurzreferat

Tonminerale aus Schichtköpfen von Schiefern der Buckinghorse Formation der Unterkreide (4250 Fuß mächtig) wurden untersucht, um das Ausmaß der Diagenese und ihre Fähigkeit zur Ölbildung abzuschätzen. Der Kristallinitätsindex, das Schärfeverhältnis, der Prozentgehalt des 2M Polymorphs am Illitanteil und das Vorkommen besonderer Minerale wurden in der gesamten Tonfraktion bestimmt, während die feinste Tonfraktion durch Röntgenbeugung, differentialthermoanalytisch, thermogravimetrisch, differentialthermogravimetrisch, infrarotspektroskopisch und durch Bestimmung der spezifischen Oberfläche und der chemischen Zusammensetzung untersucht wurden. Mit Hilfe der aus diesen Untersuchungen erhaltenen Informationen und veröffentlichter Ergebnisse wurde ein Klassifikationsschema entwickelt, das tonmineralogische Veränderungen zum diagenetischen Umwandlungsgrad und der Lagerungstiefe in Beziehung setzt.

Die Werte der Korngrößenfraktion <2 μm zeigen, daß der Kristallinitätsindex mit zunehmender Lagerungstiefe abnimmt, während das Schärfeverhältnis und der als 2M Polymorph vorliegende Illitanteil ansteigen. Die mit der Fraktion <0·08 μm erhaltenen Ergebnisse lassen erkennen, daß ein aus 3 Komponenten bestehendes Wechsellagerungstonmineral vorliegt. Darüberhinaus ergeben Fourier-Analysen sowie chemische und physikochemische Analysen, daß sowohl das Verhältnis des Anteils nichthydratisierter Tone (Illite) zu dem hydratisierter Tone als auch der K2O-Gehalt der Tone mit zunehmender Lagerungstiefe ansteigen. Kationenaustauschkapazität und spezifische Oberfläche nehmen mit der Lagerungstiefe ab.

Auf der Grundlage eines Klassifikationsschemas, das durch Kombination von Kriterien und Werten aus den Untersuchungen von Weaver (1961a), Kubler (1966), Burst (1969) und Dunoyer de Seconzac (1970) aufgestellt wurde, fallen die oberen und mittleren Teile der Formation (die oberen 3250 Fuß) in den mittleren Bereich der Diagenese, während der untere Teil (1000 Fuß) dem Beginn einer späten Phase der Diagenese zuzuordnen ist. Nach den Begriffen der Arbeit von Burst (1969) stellen die oberen 3250 Fuß einen Übergang zwischen den Stabilitäts- und Dehydratationszonen dar. Dies deutet an, daß vor Eintreten der Hebung die Kohlenwasserstoffe im Wanderungsprozeß begriffen waren. Die unteren 1000 Fuß der Formation sind der Zone beschränkter Dehydratation zuzuordnen, was zeigt, daß die Kohlenwasserstoffwanderung abgeschlossen sein sollte.

Резюме

Резюме

Исследовали глинистые минералы обнаженных пород глинистого сланца нижнего мелового периода Букингхорса (толщиной 4250 фут), чтобы определить степень их диагенеза и их потенциал генерации нефти. На целой фракции глины изучали показатель степени кристал-лизации, остроугольность, процентное содержание иллита, являющимся полиморфом 2М и присутствие разрозненных частиц минералов, а очень малую фракцию глины подвергали рентгенографическому структурному, дифференциально-термическому, термогравиметри-ческому, дифференциально-термогравиметрическому, ИК-пектроскопическому анализам и также анализу поверхностной площади. Посредством информации полученной этими исследо-ваниями и из опубликованных данных, разработали схему классификации, относящую разно-образия минералогии глины к диагенетическим периодам и к глубине залегания.

По данным о фракции 2 μм видно, что в зависимости от глубины залегания степень крис-таллизации уменьшается, в то время как остроугольность и процентное содержание иллита, являющимся полиморфом 2М, повышаются. Результаты исследования фракции <0,08 μм показали, что существует переслаивающийся трехсоставной глинистый минерал. Кроме того, преобразование Фурье и химический и физико-химический анализы указали, что как соотно-шение негидратировавшейся глины (иллит) к гидратировавшейся глине, так и содержание К2O в глине повышаются чем глубже залегает минерал, а катионообменная способность и площадь поверхности при этом понижаются.

На основании схемы классификации, выработанной комбинацией критерий и данных взятых из исследований Вивера (1961а); Кублера (1966); Бурста (1969) и Дуноейра де Секонзака (1970), верхняя и средняя части формации (верхняя 3250 фут) приходятся на среднюю стадию преобразования осадков в горные породы, в то время как нижняя часть (1000 фут) относится к началу позднего диагенеза. По работе Бурста (1969), верхние 3250 фут находятся в переходной стадии между зонами устойчивости и дегидратации указывающими, что до взброса, угле-водороды, вероятно, подвергались перемещению.

Type
Research Article
Information
Clays and Clay Minerals , Volume 22 , Issue 4 , August 1974 , pp. 319 - 335
Copyright
Copyright © Clay Minerals Society 1974

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Footnotes

*

Joint contribution, No. 475 (S.R.I.).

References

Aguilera, N. H. and Jackson, M. L., (1953) Iron removal from soils and clays Soil Sci. Soc. Am. Proc. 17 359–364.CrossRefGoogle Scholar
Andreev, P. F., Bogomolov, A. I., Dobyanskii, A. F. and Kartsev, A. A., (1968) Transformation of Petroleum in Nature Oxford Pergamon Press.CrossRefGoogle Scholar
Barshad, I., (1948) Vermiculite and its relation to biotite Am. Mineralogist 33 655–678.Google Scholar
Barshad, I. and Black, C. A., (1965) Thermal analysis techniques for mineral identification and mineralogical composition Methods of Soil Analysis Wisconsin Am. Soc. Agric. 699–742.Google Scholar
Brown, G., (1961) X-Ray Identification and Crystal Structure of Clay Minerals 2nd London Mineralogical Soc.Google Scholar
Brydon, J. E., Rice, H. M. and Scott, G. C., (1963) The recovery of clays from suspension by freeze-drying Can. J. Soil Sci. 43 404–405.CrossRefGoogle Scholar
Burst, J. F., (1959) Postdiagenetic clay-mineral environmental relationship in the Gulf Coast Eocene Proc. 6th Natl. Conf. Clays and Clay Minerals, Nat. Res. Council Publ. 1957 327–341.Google Scholar
Burst, J. F., (1969) Diagenesis of Gulf Coast Clayey sediments and its possible relationship to petroleum migration Bull. Am. Assoc. Petrol. Geologist 53 73–93.Google Scholar
Cassidy, M. M. and Mankin, D. J., (1960) Chlorox use in preparation of black shales for clay mineral analysis Oklahoma Geology Notes 20 275–281.Google Scholar
Cesari, M. and Allegra, G., (1967) The intensity of X-rays diffracted by mono-dimensionally disordered structures. Case of identical layers and three different translation vectors Acta Cryst. 23 200–205.CrossRefGoogle Scholar
Cesari, M., Morelli, G. L. and Favretto, L., (1965) The determination of the type stacking in mixed-layer minerals Acta Cryst. 18 189–196.CrossRefGoogle Scholar
Chamney, T. P., Casey, R. and Rawson, P. F., (1973) Micropaleontological correlation of the Canadian boreal Lower Cretaceous; Boreal Lower Cretaceous Geol. J. Spec. Issue No. 5 Liverpool Seel House Press.Google Scholar
Cole, W. F., (1955) Interpretation of differential thermal curves of mixed layer minerals of illite and montmorillonite Nature 175 384–385.CrossRefGoogle Scholar
Cole, W. F. and Lanchucki, C. J., (1966) Tabular data of layer structure factors for clay minerals Acta Cryst. 21 836–838.CrossRefGoogle Scholar
Colombo, V., Nagy, G. and Colombo, V., (1967) Origin and evolution of petroleum Fundamental Aspects of Petroleum Geochemistry New York Elsevier 321–336.Google Scholar
Cordell, R. J., (1972) Depths of oil origin and primary migration: A review and critique Bull. Am. Assoc. Petrol-Geologists 56 2029–2067.Google Scholar
de Seconzac, D., (1970) The transformation of clay minerals during diagenesis and lower grade metamorhism: A review Sedimentol. 15 281–396.CrossRefGoogle Scholar
Foscolos, A. E. and Barefoot, R. R., (1970) A buffering and standard addition technique as an aid in the comprehensive analysis of silicates by atomic absorption spectroscopy Geol. Surv. Can. 70–167.Google Scholar
Frey, M., (1971) The step from diagenesis to metamorphism in pelitic rocks during alpine orogenesis Sedimentol. 15 261–279.CrossRefGoogle Scholar
Greene-Kelly, R. (1957) The Differential Thermal Investigation of Clays (Edited by MacKenzie, R. C.), Chap. V, pp. 140–164. Mineralogical Society, London.Google Scholar
Jackson, M. L. and Black, C. A., (1965) Free oxides, hydroxides and amorphous aluminosilicates Methods of Soil Analysis Wisconsin Am. Soc. Agric. 478–603.Google Scholar
Jonas, E. C. and Brown, T. E., (1959) Three component interstratifications J. Sed. Petrol. 29 77–86.Google Scholar
Kartsev, A. A., Vassoevich, N. B., Geodekian, A. A., Neruchev, S. G. and Sokolov, V. A., (1971) The principal stage in the formation of petroleum Proc. fith World Petrol. Cong. New York Elsevier 1–17.Google Scholar
Khitarov, N. I. and Pugin, V. A., (1966) Behavior of montmorillonite under elevated temperatures and pressures Geochem. International 3 4 621–626.Google Scholar
Kodama, H. and Brydon, J. E., (1965) Interstratified mont-morillonite-mica clays for subsoils of the prairie provinces, Western Canada Clays and Clay Minerals, Proc. 13th Nat. Conf. Oxford Pergamon Press 151–173.Google Scholar
Kodama, H. and Brydon, J. E., (1968) A study of clay minerals in podzol soils in New Brunswick, Eastern Canada Clay Minerals Bull. 7 295–309.CrossRefGoogle Scholar
Kodama, H. and Oinuma, K., (1963) Identification of kaolin minerals in the presence of chlorite by X-ray diffraction and infrared absorption spectra Clays and Clay Minerals, 11th Conf. Oxford Pergamon Press 236–249.Google Scholar
Kubler, B., (1966) La cristallinite d’illite et les zones tout à fait supérieur du métamorphisme Colloque sur les Etages Tectoniques à la Baconnière Paris Neuchàtel 105–122.Google Scholar
Long, G. and Neglia, S., (1968) Composition de l’eau interstitielle des argiles et diagènes des minéraux argilleux Rev. Inst. Franc. Pétrole 25 53–69.Google Scholar
MacEwan, D. M. C., (1956) Fourier transform methods for studying X-ray scattering from lamellar systems, E. A direct method for analyzing interstratified mixtures Kolloid-Z. 149 96–108.CrossRefGoogle Scholar
MacEwan, D. M. C., Ruiz, Amil A. and Brown, G. (1961) The X-Ray Identification and Crystal Structure of Clay Minerals: (Edited by Brown, G.) Chapt. XI, p. 393. Mineralogical Society, London.Google Scholar
Maxwell, D. T. and Hower, J., (1967) High-grade diagenesis and low grade metamorphism of illite in the Precambrian Belt Series Am. Mineralogist 52 843–857.Google Scholar
Mirchink, M. F., Ali-Zade, A. A., Bakirov, A. A., Veber, V. V., Vassoevich, N. B., Dvali, M. F., Maximov, S. P., Simakov, S. N., Sokolov, V. Z. and Trofimuk, A. A., (1971) Main concepts of the theory of oil and gas origin and their accumulation in the light of the most recent investigations Proc. of the 8th World Petrol. Cong New York Elsevier.Google Scholar
Muffler, L. J. and White, D. E., (1969) Active metamorphism of Upper Cenozoic sediments in the Salton Sea geothermal field and the Salton Trough, Southeastern California Bull. Geol. Soc. Am. 80 157–180.CrossRefGoogle Scholar
Oinuma, K. and Kodama, H., (1967) Use of infrared absorption spectra for identification of clay minerals in sediments J. Toyo Univ. Natl. Sci. 7 1–23.Google Scholar
Perry, E. and Hower, J., (1970) Burial diagenesis in Gulf Coast pelitic sediments Clays and Clay Minerals 18 165–177.CrossRefGoogle Scholar
Perry, E. and Hower, J., (1972) Late stage dehydration in deeply buried peletic sediments Am. Assoc. Petr. Geologists, Bull. 56 2013–2021.Google Scholar
Pham, T. H. and Brindley, G. W., (1970) Methylene blue absorption by clay minerals. Determination of surface areas and cation exchange capacities; (Clay-Organic studies XVIII) Clays and Clay Minerals 18 203–212.Google Scholar
Powers, M. C., (1959) Adjustment of clays to chemical change and the concept of equivalence level Proc. Natl. Conf. Clays Clay Minerals, 6th Natl. Acad. Sci. Natl. Res. Council, Publ., 1957 309–326.Google Scholar
Powers, M. C., (1967) Fluid release mechanisms in compacting marine mudrocks and their importance in oil exploration Am. Assoc. Petrol. Geologists Bull. 51 1240–1253.Google Scholar
Price, L. C., (1973) Solubility of hydrocarbons and petroleum in water as applied to primary migration of petroleum .Google Scholar
Reynolds, R. C., (1967) Interstratification clay systems: Calculation of the total one-dimensional diffraction function Am. Mineralogist. 52 661–672.Google Scholar
Sarkissyan, S. G., (1972) Origin of authigenic clay minerals and their significance in petroleum geology Sediment. Geol. 7 1–22.CrossRefGoogle Scholar
Stott, D. F., (1967) Jurassic and Cretaceous stratigraphy between Peace and Tetsa Rivers, Northeastern British Columbia Geol. Surv. Can. 66–67.Google Scholar
Stott, D. F., (1968) Lower Cretaceous Bullhead and Fort St. John Groups, between Smoky and Peace Rivers, Rocky Mountain Foothills, Alberta and British Columbia Geol. Surv. Can., Bull 152.Google Scholar
Stott, D. F., (1968) Cretaceous stratigraphy between Tetsa and La Biche Rivers, Northeastern British Columbia Geol. Surv. Can. .CrossRefGoogle Scholar
Stott, D. F., (1972) Cretaceous stratigraphy, Northeastern British Columbia Proc. 1st Geol. Conf. Western Canada .Google Scholar
Teodorovich, G. I. and Konyukhov, A. I., (1970) Mixed layer minerals in sedimentary rocks as indicators of the depth of their catagenetic alteration Dokl. Akad. Nauk SSSR 191 174–176.Google Scholar
van Moort, J. C., (1971) A comparative study of the diagenetic alteration of clay minerals in Mesozoic shales from Papua, New Guinea, and in Tertiary shales from Louisiana, U.S.A. Clays and Clay Minerals 19 1–20.CrossRefGoogle Scholar
Velde, B. and Hower, S., (1963) Petrological significance of illite and polymorphism in Paleozoic sedimentary rocks Am. Mineralogist 48 1239–1254.Google Scholar
Weaver, C. E., (1960) Possible uses of clay minerals in search for oil Bull. Am. Assoc. Petrol. Geologists 44 1505–1518.Google Scholar
Weaver, D. E., (1961) Minerals of the Ouachita structural belt and adjacent foreland in the Ouachita System Bur. Econ. Geol. Publ. 6120 147–162.Google Scholar
Weaver, C. E., (1961) Clay mineralogy of the late Cretaceous rocks of the Washakie Basin Wyo. Geol. Assoc. 16th Ann. Field Conf. Guidebook 148–154.Google Scholar
Weaver, C. E., (1965) Potassium content of illites Sci. 147 603–605.CrossRefGoogle Scholar
Weaver, C. E., Nagy, B. and Colombo, V., (1967) The significance of clay minerals in sediments Fundamental Aspects of Petroleum Geochemistry New York Elsevier 37–75.Google Scholar
Weaver, C. E., Beck, K. C. and Pollard, C. O., (1971) Clay water diagenesis during burial: How mud becomes gneiss Geol. Soc. Am. 1–78.CrossRefGoogle Scholar
Weaver, C. E. and Wampler, J. M., (1970) K, Ar, illite burial Bull. Geol. Soc. Am. 81 3423–3430.CrossRefGoogle Scholar
Yerofeyev, V. F., (1972) Geothermal activity at depth and distribution of deposits of hydrocarbons Internatl. Geol. Review 14 49–53.CrossRefGoogle Scholar