Hostname: page-component-848d4c4894-hfldf Total loading time: 0 Render date: 2024-04-30T13:17:21.764Z Has data issue: false hasContentIssue false

Formation of late Caledonian subvolcanic breccia pipes at Cruachan Cruinn, Grampian Highlands, Scotland

Published online by Cambridge University Press:  03 November 2011

I. M. Platten
Affiliation:
Department of Geology, City of London Polytechnic, Walburgh House, Bigland Street, London El 2NG, England
M. S. Money
Affiliation:
Department of Geotechnical Engineering, Drummond Building, University of Newcastle upon Tyne, Newcastle upon Tyne NE1 7RU, England

Abstract

Pipe-shaped breccia bodies associated with diorite intrusions are composed mainly of angular clasts of local schists with a few transported clasts of quartzite. Plate shaped fragments are commonly oriented to define planar fabrics in the breccias. These features indicate the operation of gas fluidisation within the pipes and both entrainment and expanded bed conditions are inferred. The fabrics result from the collapse of the fluidised suspensions as the gas flow declined. Dilational fracture patterns in the country rock comparable with the stress release patterns found around mine shafts can be matched with the fractures required to produce the angular schist clasts. It is concluded that fracturing and the introduction of fragments into the fluidised breccia system was a continuous process and that the pipe diameter increased progressively with time. Microdiorite sheets and related stock like bodies of diorite cut and metamorphose the breccias. Compaction, hornfelsing and hydrothermal alteration also contributed to breccia formation.

Type
Research Article
Copyright
Copyright © Royal Society of Edinburgh 1987

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Allman-Ward, P., Halls, C., Rankin, A. & Bristow, C. M. 1982. An intrusive hydrothermal breccia body at Wheal Remfry in the western part of the St Austell granite pluton, Cornwall, England. In Evans, A. M. (ed.) Metallisation associated with acid magmatism, 128. Chichester: Wiley.Google Scholar
Anderson, J. G. C. 1935. The Arrochar Intrusive Complex. GEOL MAG 72, 263–83.Google Scholar
Anderson, J. G. C. 1937. Intrusions of the Glen Falloch area. GEOL MAG 74, 458–68.Google Scholar
Bailey, E. B. 1960. The geology of Ben Nevis and Glen Coe and the surrounding country. 2nd end. MEM GEOL SURV G B.Google Scholar
Bailey, E. B., Clough, C. T., Wright, W. B., Richey, J. E. & Wilson, G. V. 1924. The Tertiary and post-Tertiary geology of Mull, Loch Aline and Oban. MEM GEOL SURV SCOTLAND.Google Scholar
Bowes, D. R. & Wright, A. E. 1961. An explosion-breccia complex at Back Settlement, near Kentallen, Argyll. TRANS GEOL SOC EDINBURGH 18, 293313.Google Scholar
Bowes, D. R. & Wright, A. E. 1967. The explosion-breccia pipes near Kentallen, Scotland, and their geological setting. TRANS R SOC EDINBURGH 67, 109–43.Google Scholar
Calderbank, P. H. & Toor, F. D. 1971. Fluidised beds as catalytic reactors. In Davidson, J. F. & Harrison, D. (eds) Fluidisation, 383430. London: Academic Press.Google Scholar
Cloos, H. 1941. Bau und Tatigkeit von Tuffschloten. Untersuchungen an dem Swabischen vulkan. GEOL RDSCH 32, 709800.Google Scholar
Droop, G. T. R. & Treloar, P. J. 1981. Pressures of metamorphism in the thermal aureole of the Etive Granite Complex. SCOTT J GEOL 17, 85102.Google Scholar
Francis, E. H. & Hopgood, A. M. 1970. Volcanism and the Ardross Fault, Fife. SCOTT J GEOL 6, 162–85.Google Scholar
French, W. J. 1966. Appinitic intrusions clustered around the Ardara Pluton, County Donegal. PROC R IRISH ACAD 64B, 303–22.Google Scholar
French, W. J. 1977. Breccia-pipes associated with the Ardara Pluton, County Donegal. PROC R IRISH ACAD 77B, 101–17.Google Scholar
Gates, O. 1959. Breccia pipes of the Shoshone Range, Nevada. ECON GEOL 54, 790815.Google Scholar
Hardie, W. G. 1963, Explosion-breccias near Stob Mhic Mhartuin, Glen Coe, Argyll, and their bearing on the origin of the nearby flinty crush-rock. TRANS GEOL SOC EDINBURGH 19, 426–38.Google Scholar
Hardie, W. G. 1973. The petrology of quartzite breccias from an early linear vent, Glen Coe, Argyll. SCOTT J GEOL 9, 4555.Google Scholar
Holdaway, M. J. & Lee, S. M. 1977. Fe–Mg cordierite stability in high grade pelitic rocks based on experimental, theoretical and natural observations. CONTRIB MINERAL PETROL 63, 175–98.Google Scholar
Leva, M. & Wen, Y. C. 1971. Elutriation. In Davidson, J. F. & Harrison, D. (eds) Fluidisation, 627650. London: Academic Press.Google Scholar
Money, M. S. 1963. The dioritic intrusions and associated breccias clustered around the Glen Fyne Granite. Unpublished Ph.D. Thesis, University of London.Google Scholar
Morton, D. J. 1979. Palaeogeographical evolution of the Lower Old Red Sandstone basin of the western Midland Valley. SCOTT J GEOL 15, 97116.Google Scholar
Nichols, T. C. Jr. & Abel, J. F. Jr. 1975. Mobilised residual energy a factor in rock deformation. BULL ASS ENG GEOL 12, 213–25.Google Scholar
Norton, D. L. & Cathles, L. M. 1973. Breccia pipes – products of exsolved vapor from magmas. ECON GEOL 68, 540546.Google Scholar
Obert, L. & Duval, W. I. 1967. Rock mechanics and the design of structures in rock. New York: Wiley.Google Scholar
Pattison, D. & Harte, B. 1985. A petrogenetic grid for pelites in the Ballachulish and other Scottish thermal aureoles. J GEOL SOC LONDON 142, 728.Google Scholar
Pitcher, W. S. & Berger, A. R. 1972. The geology of Donegal: a study of granite emplacement and unroofing. New York: Wiley.Google Scholar
Pitcher, W. S. & Read, H. H. 1952. An appinitic intrusion breccia at Kilkenny, Maas, Co. Donegal. GEOL MAG 89, 326–8.Google Scholar
Phillips, W. J. 1972. Hydraulic fracturing and mineralisation. J GEOL SOC LONDON 128, 337–59.Google Scholar
Platten, I. M. 1972. Caledonian breccia pipes in Appin and Loch Lomondside, Argyll. J GEOL SOC LONDON 129, 106.Google Scholar
Platten, I. M. 1982a. A late Caledonian breccia dyke swarm in Glen Creran, near Glen Coe in the Grampian Highlands. GEOL MAG 119, 169–80.Google Scholar
Platten, I. M. 1982b. Partial melting of feldspathic quartzite around late Caledonian minor intrusions in Appin, Scotland. GEOL MAG 119, 413–9.Google Scholar
Platten, I. M. 1983. Partial melting of semipelite and the development of marginal breccias around a late Caledonian minor intrusion in the Grampian Highlands of Scotland. GEOL MAG 120, 3749.Google Scholar
Platten, I. M. 1984. Fluidised mixtures of magma and rock in a late Caledonian breccia dyke and associated breccia pipes in Appin, Scotland. GEOL J 19, 209–26.Google Scholar
Reynolds, D. L. 1954. Fluidisation as a geological process and its bearing on the problem of intrusive granites. AM J SCI 252, 577614.Google Scholar
Richardson, J. F. 1971. Incipient fluidisation and particulate systems. In Davidson, J. F. & Harrison, D. (eds) Fluidisation, 2664. London: Academic Press.Google Scholar
Rowe, P. N. 1971. Experimental properties of bubbles. In Davidson, J. F. & Harrison, D. (eds) Fluidisation, 121192. London: Academic Press.Google Scholar
Sawkins, F. J. 1984. Metal deposits in relation to plate tectonics. Berlin: Springer-Verlag.Google Scholar
Sillitoe, R. H. & Sawkins, F. J. 1971. Geologic, mineralogic and fluid inclusion studies relating to the origin of copper-bearing tourmaline breccia pipes, Chile. ECON GEOL 66, 1028–41.Google Scholar
Whitehead, A. B. 1971. Some problems in large scale fluidized beds. In Davidson, J. F. & Harrison, D. (eds) Fluidisation, 781814. London: Academic Press.Google Scholar
Wilshire, H. G. 1961. Layered diatremes near Sydney, New South Wales. J GEOL 69, 473–84.Google Scholar
Zenz, F. A. 1971. Regimes of fluidized behaviour. In Davidson, J. F. & Harrison, D. (eds) Fluidisation, 115. London: Academic Press.Google Scholar