OJG  Vol.2 No.3 , July 2012
Geochemical Characterization of Novokrivoyrog Metavolcanics: Tectonic Implications and Relationship with the Early Proterozoic Banded Iron Formation (BIF) of Krivoy Rog in Ukraine
ABSTRACT
The geochemical characterization of Novokrivoyrog metavolcanics (2.2 Ga) and Krivoy Rog iron ores (1.8 Ga) in Ukraine represent an important tool for the understanding of their genesis and tectono-magmatic evolution. The petrological classification of the metavolcanics on SiO2/(Zr-TiO2) and (Zr-TiO2)/(Nb/Y) Harker-type diagrams shows similarities to subalkaline andesitic basalts. An additional classification of the basalts on TAS (Na2O + K2O/SiO2) and AFM (FeO-MgO-Na2O + K2O) diagrams exhibits a variable magmatic character from calc-alkaline to tholeiitic. The distribution of High Field Strength Elements, (HSFE: Ti, Zr, Y, Hf, Nb), V, Cr, and Rare Earth Elements (REE) in most of the rocks is close to calc-alkaline basalts (CAB) and can be compared to Precambrian mid-ocean ridge basalts (MORB) where high thermal (>250°C) basaltic alteration is intensive under pH conditions between 2 and 4. These contributed to the deposition of the Krivoy Rog BIFs. Indeed REE distribution patterns of the BIFs suggest that they can be subdivided into shales and shaly BIFs (rich in LREEs since their detrital and clastic inputs are much higher) with (La/Yb)N > 1 as indication of clastic inputs; chert and cherty BIFs showing positive Eu anomaly with (La/Yb)N < 1 are similar to REE patterns of mixed hydrothermal fluids and seawater; alkaline altered BIFs whose (La/Yb)N ratio is >1 emphasizes post-depositional effects related to the enrichment of light REEs over heavy REEs with a positive Eu anomaly. The distribution of REE patterns of Krivoy Rog BIFs can finally be compared to Precambrian iron formations of mixed submarine hydrothermal fluids and seawater origin which correspond to the MORB signature of the Novokrivoyrog metavolcanics.

Cite this paper
G. M. M. Mboudou, C. E. Suh and G. T. Mafany, "Geochemical Characterization of Novokrivoyrog Metavolcanics: Tectonic Implications and Relationship with the Early Proterozoic Banded Iron Formation (BIF) of Krivoy Rog in Ukraine," Open Journal of Geology, Vol. 2 No. 3, 2012, pp. 121-135. doi: 10.4236/ojg.2012.23013.
References
[1]   M. Bau, N. J. Beukes and R. Romer, “Increase of Oxygen in the Earth Atmosphere and Hydrosphere between 2.5 and 2.4 Ga,” Mineralogical Magazine, Vol. 62A, No. 1, 1998, pp. 127-128. doi:10.1180/minmag.1998.62A.1.67

[2]   M. Bau, “Comment on Modelling of Rare Earth Element Participationing between Particles and Solution in Aquatic Environments by Y. Erel and E. M. Stolper,” Geochimica et Cosmochimica Acta, Vol. 58, No. 20, 1994, pp. 4521-4523. doi:10.1016/0016-7037(94)90353-0

[3]   M. Bau and P. Moller, “Prakambrische Chemisch-Sedimentare Mineralisationen: Spiegel der Evolution von Lith-, Hydro-und Atmosphare,” Geowissenschaften, Vol. 12, 1994, pp. 333-336.

[4]   A. V. Plotnikov, “Internal Structure and Development of the Krivoy Rog—Kremenchug Deep Fault System in the Krivoy Rog Area,” Ph.D. Thesis, Mining Institute, Krivoy Rog, 1994.

[5]   I. S. Parahnko, “Geolgical Formation and Stratigraphic Correlation of the Early Proterozoic of the Krivoyrojia,” Report Habilatation Thesis, Mining Institute, Lviv, 1995.

[6]   R. Y. Belevtsev, F. L. Zhukov and L. T. Savchenko “Accumulation Processes of Sediments in Krivoy Rog’s Iron-Silica Formations, Based on Data of Carbon and Sulphurisotopic Investigations,” The Journal of Geology, Vol. 44, 1994, pp. 94-102.

[7]   S. R. Taylor and S. M. Mclennan, “The Continental Crust: Its Composition and Evolution,” Blackwell Scientific Publications, Oxford, 1985.

[8]   J. A. Winchester and P. A. Floyd, “Chemical Discrimination of Different Magma Series and Their Differentiation Products Using Immobile Element,” Chemical Geology, Vol. 20, 1977, pp. 325-343. doi:10.1016/0009-2541(77)90057-2

[9]   T. N. Irvine and A. Baragar, “A Guide to the Chemical Classification of the Common Volcanic Rocks,” Canadian Journal of Earth Sciences, Vol. 8, No. 5, 1971, pp. 523-548. doi:10.1139/e71-055

[10]   A. Miyashiro, “Volcanic Rock Series in Island Arcs and Active Continental Margins,” American Journal of Science, Vol. 274, No. 4, 1974, pp. 321-355. doi:10.2475/ajs.274.4.321

[11]   J. A. Pearce and J. R. Cann, “Tectonic Settings of Basic Volcanic Rocks Using Trace Element Analyses,” Earth and Planetary Science Letters, Vol. 19, No. 2, 1973, pp. 290-300. doi:10.1016/0012-821X(73)90129-5

[12]   J. W. Shervais, “Ti-V Plots and the Petrogenesis of Modern Ophiolitic Lavas,” Earth and Planetary Science Letters, Vol. 59, No. 1, 1982, pp. 101-118. doi:10.1016/0012-821X(82)90120-0

[13]   P. Jakes and J. Gill, “Rare Earth Elements and the Island Arc Tholetiitic Series,” Earth and Planetary Science Letters, Vol. 9, No. 1, 1970, pp. 17-28. doi:10.1016/0012-821X(70)90018-X

[14]   M. A. Yaroschuk, B. A. Goriilsky, V. Onoprienko and E. A. Yaroschuk, “Geochemical Features of Iron-Silica Rocks in the Krivoyrojia as a Reflection of Physical and 10 Chemical Conditions during Their Sedimentation and Metamorphism,” Geoisdatelstvo, Kiev, 1975.

[15]   M. Bau, “Effects of Syn- and Post Depositional Process on the Rare Earth Elements Distribution in Precambrian Iron Formations,” European Journal of Mineralogy, Vol. 5, No. 2, 1993, pp. 257-267.

[16]   R. M. K. Khan and S. M. Naqvi, “Geology, Geochemistry and Genesis of BIF of Kushagi Schist Belt, Archean Dharwar Craton, India,” Mineralium Deposita, Vol. 31, No. 1-2, 1996, pp. 123-133. doi:10.1007/BF00225403

[17]   C. Klein and N. J. Beukes, “Geochemistry and Sedimentology of a Facies Transition from Limestone to Iron Formation Depsotion in the Early Proterozoic Transvaal Supergroup, South Africa,” Economic Geology, Vol. 84, No. 7, 1989, pp. 1733-1774. doi:10.2113/gsecongeo.84.7.1733

[18]   H. D. Holland, “The Chemical Evolution of the Atmosphere and the Oceans,” Princeton University Press, Princeton, 1980, pp. 374-407.

[19]   R. M. Garrels, “A Model for the Deposition of the Microbanded Iron Formations,” American Journal of Science, Vol. 287, No. 2, 1987, pp. 81-106. doi:10.2475/ajs.287.2.81

[20]   S. B. Jacobsen and P. M. Klose, “A Nd Isotopic Study of the Hamersley and Michipicoten Banded Iron Formations: the Source of REE and Fe in Archean Oceans,” Earth and Planetary Science Letters, Vol. 87, No. 1-2, 1988, pp. 29-44. doi:10.1016/0012-821X(88)90062-3

[21]   R. N. Belevtsev, V. V. Rechetniak and M. I. Chernovsky “The Krivoy Rog-Kremenchug Ores Province,” In: Precombrian Banded Iron Formations of the European Part of the USSR: Structure of Deposits and Ore-Provinces, Naukova Dumka, Kiev, 1989, pp. 7-18.

[22]   A. C. Campbell, M. R. Palmer, T. S. Bowers, G. P. Klinkhammer, J. M. Edmond, J. R. Lawrence, J. F. Casey, G. Thompson, S. Humphris, P. Rona and J. A. Karson “Chemistry of Hot Springs on the Mid-Atlantic Ridge,” Nature, Vol. 355, No. 6190, 1988, pp. 514-519. doi:10.1038/335514a0

[23]   C. Alibert and M. T. McCulloch, “Rare Earth Elements and Neodymium Isotopic Compositions of the Banded Iron Formation and Associated Shales of Hamersley Western Australia,” Geochimica et Cosmochimica Acta, Vol. 57, No. 1, 1993, pp. 18-204. doi:10.1016/0016-7037(93)90478-F

 
 
Top