January 2015 LIP of the Month

A 1 : 5 million-scale  Global Large Igneous Provinces GIS Dataset for the LIPs Community

Richard. E. Ernst

Dept. of Earth Sciences, Carleton University, Ottawa, Ontario, Canada K1S 5B6; Ernst Geosciences, 43 Margrave Avenue, Ottawa, Ontario, Canada K1T 3Y2; Richard.Ernst@Carleton.ca; Richard.Ernst@ErnstGeosciences.com

Given the dramatic expansion in our understanding of Large Igneous Provinces (LIPs) since their initial recognition in the early 1990s and particularly over the past decade (e.g. Coffin and Eldholm, 1994; 2005; Courtillot and Renne, 2003; Bryan and Ernst, 2008; Bryan and Ferrari, 2013; Ernst et al., 2013; Ernst, 2014), and given the importance of a GIS framework for modern geoscience investigations, it is timely to produce an updated GIS LIPs dataset (Ernst and Pisarevsky, 2015).

Large Igneous Provinces (LIPs) represent large volume (>0.1 Mkm3; frequently above >1 Mkm3), mainly mafic (-ultramafic) magmatic events of intraplate affinity, that occur in both continental and oceanic settings, and are typically of short duration (<5 m.y.) or consist of multiple short pulses over a maximum of a few 10s of m.y. They consist of volcanic packages (flood basalts), and a plumbing systems of dykes, sills and layered intrusions. Silicic, carbonatite and kimberlite magmatism, and also ore deposits may be associated. See summarizes of LIP characteristics (e.g. Coffin and Eldholm, 1994; 2005; Courtillot and Renne, 2003; Bryan and Ernst, 2008; Bryan and Ferrari, 2013; Ernst and Jowitt, 2013; Ernst, 2014). A recently updated comprehensive listing of LIP events through time is presented in Ernst (2014).

The previous LIPs dataset of Coffin (2011) included ArcGIS™ shapefiles for continental flood basalts and oceanic plateaus /ocean basin flood basalts, along with associated hotspot magmatism ranging in age back to 260 Ma plus linework for a few selected older events. The current project aims to fully expand the shapefile dataset into pre-Mesozoic time: into the Proterozoic, where the flood basalt record has been generally largely removed by erosion thus exposing the plumbing system of dykes, sills and layered intrusions, and also into the Archean, where LIP candidates have been proposed (e.g. Ernst, 2014). The ArcGIS™ dataset will eventually also include associated silicic magmatism, carbonatites, kimberlites and ore deposits as well as related structures (e.g. rifts), and interpreted mantle plume centres.

The ArcGIS™ LIPs dataset is being compiled and integrated (with appropriate referencing) from many sources, including global datasets such as: the Cenozoic-Mesozoic continental / oceanic LIP dataset (Coffin, 2011), and a global dyke swarm compilation (Ernst et al. 1996), and also regional datasets such as: for Australia (Thorne et al., 2014; see also Pirajno and Hoatson, 2012); for China (Peng, 2015); for Canada, and adjacent regions of the United States and Greenland (Buchan and Ernst, 2004, 2013); and for West Africa (Jessell et al. 2015). Shapefile linework is also being digitized from georeferenced diagrams from journal publications provided by the Geofacets tool of Elsevier (www.elsevier.com/online-tools/geofacets), from publications of the “Commission For the Geological Map of the World” (CCGM-CGMW; http://ccgm.org/, and from additional regional/national digital publications. Some LIP ArcGIS™ compilation work under contract is being funded by an Industry-Consortium Project (Ernst et al., 2013; www.supercontinent.org; www.camiro.org/exploration/ongoing-projects).

The initial version of the 1 : 5 M Global ArcGIS™ LIP dataset is being released to the above-mentioned Industry-Consortium group at the end of February 2015. Extensive subsequent revisions will be done with the input of colleagues in the LIPs community toward release of a version 2 ArcGIS™ LIPs dataset to the broader LIPs community in about one year. It is also proposed that the global ArcGIS™ LIPs dataset will be published in association with some regional and thematic ArcGIS™ LIP datasets.

This global ArcGIS™ LIPs dataset will form a framework for additional thematic databases related to LIPs, including geochemistry, geochronology, and paleomagnetism (GPMDB, MAGIC). LIP databases provide useful constraints for global Precambrian paleogeographic reconstructions, a context for understanding some global and regional environmental changes, and a useful framework for resource exploration (mineral and hydrocarbon) (e.g. Bryan and Ferrari, 2013; Ernst, 2014). One of the most important aspects of this global LIPs ArcGIS™ dataset is that it is integrating data on the volcanic component of LIPs (both flood basalts, and associated ultramafic and silicic volcanism) with data on the plumbing system component in order to develop an understanding of LIPs as an integrated system  (see December 2014 LIP of the Month).

References

Bryan, S. & Ernst, R.E. (2008). Revised definition of Large Igneous Provinces (LIPs). Earth-Science Reviews, 86: 175–202.

Bryan, S.E. & Ferrari, L. (2013). Large Igneous Provinces and Silicic Large Igneous Provinces: progress in our understanding over the last 25 years. Geological Society of America Bulletin, 125: 1053–1078.

Buchan, K.L. & Ernst, R.E. (2004). Dyke swarms and related units in Canada and adjacent regions. Geological Survey of Canada Map 2022A (scale 1:5,000,000) and accompanying booklet.

Buchan, K.L. & Ernst, R.E. (2013). Diabase dyke swarms of Nunavut, Northwest Territories, and Yukon, Canada. Geological Survey of Canada, Open File 7464.

Coffin, M.F. (2011) Digital LIPs database (version 2011). PLATES Project, UTIG University of Texas Institute for Geophysics; www.ig.utexas.edu/research/projects/plates/data/LIPS/

Coffin, M.F. & Eldholm, O. (1994). Large igneous provinces: crustal structure, dimensions, and external consequences. Review of Geophysics, 32: 1–36.

Coffin, M.F. & Eldholm, O. (2005). Large igneous provinces. In Selley, R.C., Cocks, R., & Plimer, I.R. (eds.), Encyclopedia of Geology. Elsevier: Oxford, pp. 315–323.

Courtillot, V. & Renne, P.R. (2003). On the ages of flood basalt events. Comptes Rendus Geoscience, 335: 113–140.

Ernst, R.E. (2014).  Large Igneous Provinces. Cambridge University Press, 653 p.

Ernst, R.E. & Bell, K. (2010). Large Igneous Provinces (LIPs) and carbonatites. Mineralogy and Petrology, 98: 55–76.

Ernst, R.E. & Jowitt, S.M. (2013). Large Igneous Provinces (LIPs) and Metallogeny. Society of Economic Geologists Special Publication, 17: 17–51.

Ernst, R.E. & Pisarevsky, S.A. (2015). Databases related to Large Igneous Provinces. Abstract EGU2015-8592. European Geosciences Union (EGU) General Assembly 2015 (12-17 April 2015, Vienna

Ernst, R.E., Buchan, K.L., West, T.D., & Palmer, H.C. (1996). Diabase (dolerite) dyke swarms of the world, first edition. Geological Survey of Canada Open-File 3241, includes map, scale 1:35 000 000 at Equator.

Ernst, R.E., Bleeker, W., Söderlund, U., & Kerr, A.C. (2013). Large Igneous Provinces and supercontinents: Toward completing the plate tectonic revolution. Lithos, 174: 1–14. 
[This paper discusses the Industry-funded project “Reconstruction of Supercontinents Back To 2.7 Ga Using The Large Igneous Province (LIP) Record: With Implications For Mineral Deposit Targeting, Hydrocarbon Resource Exploration, and Earth System Evolution”(www.supercontinent.org; www.camiro.org/exploration/ongoing-projects) which over the past 5 years has produced >200 U-Pb baddeleyite (and some zircon) ages on LIPs, particularly their dolerite dyke swarms, throughout the world.]

Jessell, M.  Santoul, J. Baratoux, L., Youbi, N., Ernst, R.E., Metelka, V., Miller, J., & Perrouty, S. (2015) An Updated Map of West African Mafic Dykes. Journal of African Earth Sciences (in press).

Peng, P. (2015) Precambian mafic dyke swarms of the North China craton and their geological implications. Science China, Earth Sciences (in press).

Thorne, J.P., Highet, L.M., Cooper, M., Claoue-Long, J.C., Hoatson, D.M., Jaireth, S., Huston, D.L., & Gallagher, R. G. (2014). Australian Mafic-Ultramafic Magmatic Events GIS Dataset, 1:5 000 000 scale [Digital Dataset]. Geoscience Australia, Commonwealth of Australia, Canberra; www.ga.gov.au

Pirajno, F. & Hoatson, D.M. (2012). A review of Australia’s large igneous provinces and associated mineral systems: implications for mantle dynamics through geological time. Ore Geology Reviews, 48: 2–54.