South Mathiatis: An unusual volcanogenic sulphide deposit in the Troodos ophiolite of Cyprus

Abstract

The South Mathiatis deposit in the Troodos ophiolite of Cyprus is located within Lower Pillow Lavas in the central part of the Mitsero (Ayios Epiphanios) graben, and is characterised by elevated Zn contents, and a hydrothermal mineral assemblage in which galena is locally an important component and barite is a common gangue mineral, features which place it apart from other Cyprus-type deposits. The mineralisation is hosted within a gently dipping sheet flow-dominated sequence of lavas with common autobrecciation textures and associated hyaloclastites, and is stratigraphically controlled between lava flows, locally floored by unmineralised hyaloclastites. The environment of extrusion is interpreted as a ponded sequence, similar to the adjacent Agrokipia deposit. The Zn-rich mineralisation appears to be controlled by local structures which allowed access to the hydrothermal fluids, which then migrated laterally along lithologically favourable concordant zones. The sulphide assemblage is dominated by sphalerite together with ubiquitous pyrite; however, both chalcopyrite and galena are locally important; quartz and barite comprise the gangue-mineral assemblage. Red jasper is spatially associated with the sulphide mineralisation and displays abundant filamentous structures similar to forms identified in other VMS environments. Wall rock alteration associated with the mineralisation is weak, and this is reflected in the absence of a magnetic signature, in contrast to typical Cyprus deposits. The Zn mineralisation is also transparent to electrical methods suggesting that other similar deposits may be present in the ophiolite but remain as yet undetected.

Keywords

Volcanogenic sulphide deposits Troodos ophiolite Zinc Geophysics

Get full access to this article

View all access options for this article.

References

Adamides

. 1984. Cyprus volcanogenic sulphide deposits in relation to their environment of formation, PhD thesis, University of Leicester, UK.

Adamides

. 2007. A further report on the South Mathiatis deposit, with a revised resource estimation, internal report, EMED Mining Public Ltd, UK.

Barton

. Bethke

, P.M and Roedder

. 1977. Environment of ore deposition in the Creede mining district, San Juan mountains, Colorado: Part III. Progress toward interpretation of the chemistry of the ore-forming fluid for the OH vein, Econ. Geol., 72, 1–24.

Barton

and Bethke

. 1987. Chalcopyrite disease in sphalerite: Pathology and epidemiology, Am. Mineral., 72, 451–467.

Bear

. 1960. The geology and mineral resources of the Akaki–Lythrodondha area: Memoir 3, Geolog. Surv. Depart., Cyprus.

Bear

. 1963. The mineral resources and mining industry of Cyprus: Bull. No. 1, Geol. Surv. Dept., Cyprus.

Bishop JR and Emerson

. 1999. Geophysical properties of zinc-bearing deposits, Aust. J. Earth Sci., 3, 311–328.

Boyce

, Little

CTS

and Russell

. 2003. A new fossil vent biota in the Ballynoe barite deposit, Silvermines, Ireland: Evidence for intracratonic sea-floor hydrothermal; activity about 352 Ma, Econ. Geol., 98, 649–656.

Christoforou

. 1974. Geochemical survey at Mathiatis (Mitsero), Internal Report, Hellenic Mining Company Ltd, Nicosia, Cyprus.

10.

Christoforou

. 1975. Cupriferous sulphide mineralisation of the Kokkinoyia mine. Unpublished Master's dissertation, Cardiff, UK.

11.

Constantinou

and Govett

GJS

. 1973. Geology, geochemistry and genesis of Cyprus sulfide deposits, Econ. Geol., 68, 843–858.

12.

Deer

, Howie

and Zussman

. 1966. An introduction to the rock-forming minerals, 1st edn, London, Longmans, Green and Co. Ltd.

13.

Duhig

, Stolz

, Davidson

and Large

. 1992a. Cambrian microbial and silica gel textures in silica iron exhalites from the Mount Windsor volcanic belt, Australia: Their petrography, chemistry and origin, Econ. Geol., 87, 764–784.

14.

Duhig

, Davidson

and Stolz

. 1992b. Microbial involvement in the formation of Cambrian sea-floor silica–iron oxide deposits, Australia, Geology, 20, 511–514.

15.

Emerson

and Moyer

. 2002. Neutrophilic Fe-oxidising bacteria are abundant at the Loihi seamount hydrothermal vents and play a major role in Fe oxide deposition, Appl. Environ. Microb., 3085–3093.

16.

Franklin

, Lydon

and Sangster

. 1981. Volcanic-associated massive sulfide deposits, Econ. Geol., Seventy-fifth Ann. Vol., 485–627.

17.

Galley

, Hannington

and Jonasson

. 2007. Volcanogenic massive sulphide deposits, in Mineral deposits of Canada: A synthesis of major deposit-types, District metallogeny, the evolution of geological provinces, and exploration methods, (ed. Goodfellow

W D

), 141–162, Min. Dep. Div. Spec. Pub. 5, Geolog. Assoc. Canada.

18.

Gass

and Masson-Smith

. 1963. The geology and gravity anomalies of the Troodos Massif, Philos. Trans. R. Soc. Lond., A255, 417–467.

19.

Grenne

and Slack

. 2003. Paleozoic and Mesozoic silica-rich seawater. Evidence from hematitic chert (jasper) deposits, Geology, 31, 319–322.

20.

Hall

. 1987. Interaction of submarine volcanic and high-temperature hydrothermal activity proposed for the formation of the Agrokipia volcanic massive sulfide deposits of Cyprus, Can. J. Earth Sci., 29, 1928–1936.

21.

Hannington

, Humphris

, Galley

, Herzig

and Petersen

. 1998. Comparison of the Tag mound and stockwork complex with Cyprus-type massive sulfide deposits, Proc. Ocean Dril. Program, Sci. Results, 158, 389–415.

22.

Haymon

. 1982. Hydrothermal deposition on the East Pacific Rise, at 21° N, unpublished PhD thesis, University of California, San Diego, CA, USA.

23.

Herzig

. 1988. A mineralogical, geochemical and thermal profile through the Agrokipia B hydrothermal sulfide deposit, Troodos ophiolite complex, Cyprus, in Base metal sulfide deposits (ed. Friedrich

G H

and Herzig

P M

), 182–215, Berlin, Heidelberg, Springer Verlag.

24.

Herzig

and Hannington

. 1995. Polymetallic massive sulfides at the modern ocean seafloor: A review, Ore Geol. Rev., 10, 95–115.

25.

Hopkinson

, Roberts

, Herrington

and Wilkinson

. 1998. Self-organisation of submarine hydrothermal siliceous deposits: evidence from the TAG hydrothermal mound, 26° N Mid-Atlantic Ridge, Geology, 26, 347–350.

26.

Hopkinson

, Roberts

, Herrington

and Wilkinson

. 1999. The nature of crystalline silica from the TAG submarine hydrothermal mount, 26° N Mid-Atlantic Ridge, Contrib. Mineral. Petrol., 137, 342–350.

27.

Hutchinson

and Searle

. 1971. Stratabound pyrite deposits in Cyprus and relations to other sulphide ores, Soc. Min. Geol. Jpn, Special Issue 3, 198–205.

28.

Jorge

RCGS

, Relvas

JMRS

and Barriga

FJAS

. 2005. Silica gel microstructures in siliceous exhalites at the Soloviejo manganese deposit, Spain, Abstracts of SGA Meeting, Beijing, China, August, Session 6–9, 631–634.

29.

Juniper

and Fouquet

. 1988. Filamentous iron-silica deposits from modern and ancient hydrothermal sites, Can. Mineral., 26, 859–869.

30.

Kalogeropoulos

. 1985. Discriminant analysis for evaluating the use of lithogeochemistry along the Tetsusekiei Horizon as an exploration tool in search for Kuroko type ore deposits, Min. Depos., 20, 135–142.

31.

Kalogeropoulos

and Scott

. 1983. Mineralogy and geochemistry of tuffaceous exhalites (tetsusekiei) of the Fukazawa mine, Hokuroku district, Japan, Econ. Geol. Mon. 5, 412–432.

32.

Koski

, Clague

and Oudin

. 1984. Mineralogy and chemistry of massive sulfide deposits from the Juan de Fuca Ridge, Bull. Geol. Soc. Am., 95, 930–945.

33.

Maliotis

. 1978. Applicability and limitations of the IP in Cyprus, unpublished PhD thesis, University of Leicester, UK.

34.

Moores

and Vine

. 1971. The Troodos massif, Cyprus, and other ophiolites as oceanic crust: evaluation and implications, Philos. Trans. R. Soc. Lond., 268, 443–466.

35.

Rona

. 1978. Criteria for recognition of hydrothermal mineral deposits in oceanic crust, Econ. Geol., 73, 135–160.

36.

Rona

. 2005. TAG hydrothermal field: A key to modern and ancient seafloor hydrothermal VMS ore-forming systems, Abstracts of SGA Meeting, Beijing, China, August, 6–23, 687–690.

37.

Robinson

, Melson

, O'Hearn

and Schmincke

H-U

. 1983. Volcanic glass compositions of the Troodos ophiolite, Cyprus, Geology, 11, 400–404.

38.

Solomon

and Walshe

. 1979. The formation of massive sulfide deposits on the sea floor, Econ. Geol., 74, 797–813.

39.

Varga

and Moores

. 1985. Spreading structure of the Troodos ophiolite, Cyprus, Geology, 13, 846–850.