Bulletin of Volcanology

, Volume 72, Issue 4, pp 469–485 | Cite as

Explosive lava–water interactions II: self-organization processes among volcanic rootless eruption sites in the 1783–1784 Laki lava flow, Iceland

  • Christopher W. Hamilton
  • Sarah A. Fagents
  • Thorvaldur Thordarson
Research Article

Abstract

We have applied quantitative geospatial analyses to rootless eruption sites in the Hnúta and Hrossatungur groups of the 1783–1784 Laki lava flow to establish how patterns of spatial distribution can be used to obtain information about rootless cone emplacement processes and paleo-environments. This study utilizes sample-size-dependent nearest neighbor (NN) statistics and Voronoi tessellations to quantify the spatial distribution of rootless eruption sites and validate the use of statistical NN analysis as a remote sensing tool. Our results show that rootless eruption sites cluster in environments with abundant lava and water resources, but competition for limited groundwater in these clusters can cause rootless eruption sites to develop repelled distributions. This pattern of self-organization can be interpreted within the context of resource availability and depletion. Topography tends to concentrate lava (fuel) and water (coolant) within topographic lows, thereby promoting explosive lava–water interactions in these regions. Given an excess supply of lava within broad sheet lobes, rootless eruption sites withdraw groundwater from their surroundings until there is insufficient water to maintain analogs to explosive molten fuel–coolant interactions. Rootless eruption sites may be modeled as a network of water extraction wells that draw down the water table in their vicinity. Rootless eruptions at locations with insufficient groundwater may either fail to initiate or terminate before explosive activity has ceased at nearby locations with a greater supply of water, thus imparting a repelled distribution to observed rootless eruption sites.

Keywords

Volcanic rootless cones Pseudocraters Phreatomagmatic Explosive lava–water interactions Laki Iceland Mars 

Notes

Acknowledgments

We thank Karen Pascal for her assistance in the field; Samuel Hulme and Ciarán Beggan for their assistance with GMT and MATLAB, respectively; Steve Baloga and Barbara Bruno for discussions relating to NN analysis; Benjamin Brooks and the Pacific GPS facility for providing DGPS survey equipment and post-processing resources; Bruce Houghton and Scott Rowland for their comments and suggestions during the preparation of this manuscript; Laszlo Keszthelyi and Lori Glaze for their thoughtful and thorough reviews; and financial support from the National Aeronautics and Space Administration (NASA) Mars Fundamental Research Program (MFRP) grant NNG05GM08G, NASA Mars Data Analysis Program (MDAP) grant NNG05GQ39G, Geological Society of America (GSA), and Icelandic Centre for Research (RANNÍS). SOEST publication number 1800. HIGP publication number 7806.

Supplementary material

445_2009_331_MOESM1_ESM.pdf (145 kb)
Appendix 1 (PDF 95 kb)
445_2009_331_MOESM2_ESM.pdf (26 kb)
Appendix 2 (PDF 26.7 kb)

References

  1. Allen CC (1979) Volcano–ice interactions on Mars. J Geophys Res 84:8048–8059CrossRefGoogle Scholar
  2. Balakrishnan N (1991) Handbook of the logistic distribution. Marcel Dekker, New YorkGoogle Scholar
  3. Baloga SM, Glaze LS, Bruno BC (2007) Nearest-neighbor analysis of small features on Mars: applications to tumuli and rootless cones. J Geophys Res 112:E03002. doi: 10.1029/2005JE002652 CrossRefGoogle Scholar
  4. Beggan C, Hamilton CW (2009) New image processing software for analyzing object size-frequency distribution, geometry, orientation, and spatial distribution. Comput Geosci. doi: 10.1016/j.cageo.2009.09.003
  5. Bruno BC, Fagents SA, Thordarson T, Baloga SM, Pilger E (2004) Clustering within rootless cone groups on Iceland and Mars: effect of nonrandom processes. J Geophys Res 109:E07009. doi: 10.1029/2004JE002273 CrossRefGoogle Scholar
  6. Bruno BC, Fagents SA, Hamilton CW, Burr DM, Baloga SM (2006) Identification of volcanic rootless cones, ice mounds, and impact craters on Earth and Mars: using spatial distribution as a remote sensing tool. J Geophys Res 111:E06017. doi: 10.1029/2005JE002510 CrossRefGoogle Scholar
  7. Clark PJ, Evans FC (1954) Distance to nearest neighbor as a measure of spatial relationships in populations. Ecology 35:445–453CrossRefGoogle Scholar
  8. Fagents SA, Thordarson T (2007) Rootless volcanic cones in Iceland and on Mars. In: Chapman MG (ed) The geology of Mars: evidence from earth-based analogs. Cambridge University Press, Cambridge, pp 151–177CrossRefGoogle Scholar
  9. Fagents SA, Lanagan P, Greeley R (2002) Rootless cones on Mars: a consequence of lava–ground ice interaction. In: Smellie JL, Chapman MG (eds) Volcano–ice interaction on Earth and Mars. Geol Soc Lond Spec Publ 202:295–317Google Scholar
  10. Frey H, Jarosewich M (1982) Subkilometer Martian volcanoes: properties and possible terrestrial analogs. J Geophys Res 87:9867–9879CrossRefGoogle Scholar
  11. Frey H, Lowry BL, Chase SA (1979) Pseudocraters on Mars. J Geophys Res 84:8075–8086CrossRefGoogle Scholar
  12. Glaze LS, Anderson SW, Stofan ER, Smrekar SE (2005) Statistical distribution of tumuli on pahoehoe flow surfaces: analysis of examples in Hawaii and Iceland and potential applications to lava flows on Mars. J Geophys Res 110:B08202. doi: 10.1029/2004JB003564 CrossRefGoogle Scholar
  13. Graham R (1972) An efficient algorithm for determining the convex hull of a finite planar point set. Inf Proc Lett 1:132–133CrossRefGoogle Scholar
  14. Greeley R, Fagents SA (2001) Icelandic pseudocraters as analogs to some volcanic cones on Mars. J Geophys Res 106:20527–20546CrossRefGoogle Scholar
  15. Hamilton CW, Fagents SA, Thordarson T (2007) Rootless cone archetypes and their relation to lava flow emplacement processes. Abstracts of the 2nd Volcano–Ice Interaction on Earth and Mars Conference, University of British Columbia, Vancouver, 19–22 June 2007Google Scholar
  16. Hamilton CW, Thordarson T, Fagents SA (2010) Explosive lava–water interactions I: architecture and emplacement chronology of volcanic rootless cone groups in the 1783–1784 Laki lava flow, Iceland. Bull Volcanol. doi: 10.1007/s00445-009-0330-6
  17. Head JW, Wilson L (2002) Mars: a review and synthesis of general environments and geological settings of magma/H2O interactions. In: Smellie JL, Chapman MG (eds) Volcano–ice interaction on Earth and Mars. Geol Soc Lond Spec Publ 202:27–57Google Scholar
  18. Jaeger WL, Keszthelyi LP, McEwen AS, Dundas CM, Russell PS (2007) Athabasca Valles, Mars: a lava-draped channel system. Science 317:1709–1711. doi: 10.1126/science.1143315 CrossRefGoogle Scholar
  19. Jaeger WL, Keszthelyi LP, McEwen AS, Dundas CM, Russell PS (2008a) Response to comment on “Athabasca Valles, Mars: a lava-draped channel system”. Science 320:1588c. doi: 10.1126/science.1155124 CrossRefGoogle Scholar
  20. Jaeger WL, Keszthelyi LP, McEwen AS, Milazzo MP (2008b) Phreatovolcanism in a deflating sheet flow: insights from HiRISE images of Athabasca Valles, Mars. International Association of Volcanology and Chemistry of the Earth’s Interior, General Assembly, Reykjavík, 17–22 August 2008Google Scholar
  21. Lanagan PD, McEwen AS, Keszthelyi LP, Thordarson T (2001) Rootless cones on Mars indicating the presence of shallow equatorial ground ice in recent times. Geophys Res Lett 28:2365–2367CrossRefGoogle Scholar
  22. Lotka AJ (1925) Elements of physical biology. Williams and Wilkins, BaltimoreGoogle Scholar
  23. Steingrímsson J (1788) Fulkomid Skrif um Sídueld. Safn til Sögu Íslands IV:58–69Google Scholar
  24. Thorarinsson S (1951) Laxargljufur and Laxarhraun: a tephrachronological study. Geograf Annal H1(2):1–89CrossRefGoogle Scholar
  25. Thorarinsson S (1953) The crater groups in Iceland. Bull Volcanol 14:3–44CrossRefGoogle Scholar
  26. Thordarson T (2003a) The 1783–1785 A.D. Laki-Grímsvötn eruptions I: a critical look at the contemporary chronicles. Jökull 53:1–10Google Scholar
  27. Thordarson T (2003b) The 1783–1785 A.D. Laki-Grímsvötn eruptions II: appraisal based on contemporary accounts. Jökull 53:11–47Google Scholar
  28. Thordarson T, Self S (1993) The Laki (Skaftar Fires) and Grimsvotn eruptions in 1783–85. Bull Volcanol 55:233–263CrossRefGoogle Scholar
  29. Thordarson T, Self S, Oskarsson N, Hulsebosch T (1996) Sulfur, chlorine, and fluorine degassing and atmospheric loading by the 1783–1784 AD Laki (Skaftár Fires) eruption in Iceland. Bull Volcanol 58:205–225CrossRefGoogle Scholar
  30. Verhulst V (1838) Notice sur la loi que la population suit dans son accrossement. Corr Math Phys 10:113–121Google Scholar
  31. Wohletz K (2002) Water/magma interaction: some theory and experiments on peperite formation. J Volcanol Geotherm Res 114:19–35CrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Christopher W. Hamilton
    • 1
  • Sarah A. Fagents
    • 1
  • Thorvaldur Thordarson
    • 2
  1. 1.Hawai‘i Institute of Geophysics and PlanetologyUniversity of Hawai‘iHonoluluUSA
  2. 2.School of GeosciencesUniversity of EdinburghEdinburghUK

Personalised recommendations