Stock (geology)

In geology, a stock is an igneous intrusion that has a surface exposure of less than 100 square kilometres (40 sq mi),^[1][2] differing from batholiths only in being smaller. A stock has a discordant relationship with the rocks that it intrudes. Many stocks are cupolas of hidden batholiths.^[3][2] Some circular or elliptical stocks may be volcanic plugs, which fill the vents of now extinct volcanoes.^[4][5] A boss is a small stock.^[6]

A stock of nordmarkite (quartz-alkali syenite) of Triassic age, in the Gevanim Valley, Makhtesh Ramon, southern Israel.

Examples

• the Alta and Clayton Peak stocks (composed of granodiorite), near Park City, Utah^[7]
• the Hellroaring Creek and Salal Creek stocks (of granite-granodiorite and quartz monzonite, respectively) in British Columbia, Canada^[8][9]
• the Céret stock (of gabbro and diorite) in Pyrénées-Orientales, France^[10]
• the Parashi stock (of tonalite) in La Guajira Department, Colombia^[11]
• stocks of syenite in the Caldera de Tejeda on Gran Canaria^[12]
• Ailsa Craig granitic boss, which forms a volcanic plug, in Scotland^[5]

References

1. Gabler, R.E. et al. (2009) Physical Geography (9th edition), Cengage Learning Inc., page 390.
2. Whittow, John (1984). Dictionary of Physical Geography. London: Penguin, 1984, p. 513. ISBN 0-14-051094-X.
3. Albert, Fay H. (1947). A Glossary of the Mining and Mineral Industry. Washington, D.C.: Government Printing Office. p. 200.
4. Kikauka, Andris (1996). Geological, Geochemical, and Diamond Drilling Report on the Salal 1-6 Claims, Pemberton, B.C. (Report). Sooke, British Columbia: Geo-Facts. p. 7.
5. Gillen, C. (2003). Geology and Landscapes of Scotland (2nd edition). Dunedin. ISBN 978-1780460093.
6. Coash, John R. (1967). "Geology of the Mount Velma Quadrangle, Elko County, Nevada". Nevada Bureau of Mines Bulletin. 68: 16.
7. Cook, Stephen J.; Bowman, John R. (1994). "Contact metamorphism surrounding the Alta stock: Thermal constraints and evidence of advective heat transport from calcite + dolomite geothermometry" (PDF). American Mineralogist. 79: 513–525.
8. S.G. Soloviev (2011). Compositional Features and Rare Metal Mineralization of the Hellroaring Creek Stock, Southeastern British Columbia (NTS 082F/09) – Geological Fieldwork 2011, Paper 2012-1 (PDF). British Columbia Ministry of Energy, Mines and Petroleum Resources. pp. 181–198.
9. Mustard, D. K.; Campbell, C. B. (1971). Salal Creek Molybdenum Property (Report). Government of British Columbia. pp. 6, 7, 8, 9.
10. Aguilar, C.; Liesa, M.; Reche, J.; Powell, R. (2016). "Fluid-fluxed melting and melt loss in a syntectonic contact metamorphic aureole from the Variscan eastern Pyrenees". Journal of Metamorphic Geology. 34 (4): 379–400. doi:10.1111/jmg.12187. hdl:2445/181649.
11. Martínez, Lina Fernanda; Zuluaga C., Carlos A. (2010). "Thermal modeling of pluton emplacement and associated contact metamorphism: Parashi stock emplacement in the Serranía de Jarara (Alta Guajira, Colombia)". Earth Sciences Research Journal. 14 (2).
12. Pérez Torrado, F.J.; Carracedo, J.C. (2002). "Cenozoic volcanism II - the Canary Islands – Gran Canaria". In Gibbons, W.; Moreno, T. (eds.). The Geology of Spain. The Geological Society. p. 448. ISBN 1-86239-110-6.