Modeling Volcano Growth on the Island of Hawaii: Deep-Water Perspectives
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Modeling volcano growth on the Island of Hawaii: Deep-water perspectives Peter W. Lipman and Andrew T. Calvert U.S. Geological Survey, Menlo Park, California 94025, USA ABSTRACT reasonably consistent with ages and volcano 1974; Robinson and Eakins, 2006), recognition spacing, but younger Loa volcanoes are off- of an early-alkalic (“preshield”) stage at Loihi Recent ocean-bottom geophysical surveys, set from the Kea trend in age-distance plots. Seamount (Moore et al., 1982; Garcia et al., dredging, and dives, which complement sur- Variable magma fl ux at the Island of Hawaii, 1995a), insights into volcano growth based on face data and scientifi c drilling at the Island and longer-term growth of the Hawaiian ages of submerged slope breaks and coral reefs of Hawaii, document that evolutionary stages chain as discrete islands rather than a con- (Moore and Campbell, 1987; Ludwig et al., during volcano growth are more diverse than tinuous ridge, may record pulsed magma 1991), and geodynamic models for growth rates previously described. Based on combining fl ow in the hotspot/plume source. and compositional evolution in response to plate available composition, isotopic age, and geo- motion over a hotspot (Moore and Clague, 1992; logically constrained volume data for each of INTRODUCTION DePaolo and Stolper, 1996; Ribe and Chris- the component volcanoes, this overview pro- tensen, 1999; DePaolo et al., 2001). vides the fi rst integrated models for overall This overview, inspired by the 100th anni- Until recently, compositions and ages bearing growth of any Hawaiian island. In contrast versary of the U.S. Geological Survey (USGS) on growth of Hawaiian volcanoes have largely to prior morphologic models for volcano Hawaii Volcano Observatory (HVO) in 2012, come from subaerial sampling of late eruptive evolution (preshield, shield, postshield), focuses on results of underwater studies of stages, and estimates of inception and early evo- growth increasingly can be tracked by age Hawaiian volcanoes that provide new perspec- lution have been heavily model dependent, using and volume (magma supply), defi ning wax- tives on the growth of intraplate volcanoes. volcano spacing and plate motion to infer propa- ing alkalic , sustained tholeiitic, and waning Recent studies have been especially productive gation rates and duration of edifi ce growth. The alkalic stages. Data and estimates for indi- for the Island of Hawaii (Fig. 1), where sonar present interpretive synthesis, by combining vidual volcanoes are used to model changing surveys, dives, and dredging by the University recent chemical and 40Ar/39Ar isotopic-age data magma supply during successive composi- of Hawaii, Monterey Bay Aquarium Research (mainly from underwater and drill-hole sam- tional stages, to place limits on volcano life Institute, National Oceanic and Atmospheric ples), revised edifi ce volumes, limitations from spans, and to interpret composite assembly Administration (NOAA), and USGS, and col- volcano structures and eruptive processes, and of the island. Volcano volumes vary by an laborations with the Japan Agency for Marine- geodynamic constraints, attempts to interpret order of magnitude; peak magma supply Earth Science and Technology (JAMSTEC) the growth histories of individual volcanoes and also varies sizably among edifi ces but is chal- have complemented on-land scientifi c drilling the composite growth of the entire island. While lenging to quantify because of uncertainty and abundant data from HVO. focused on construction of Hawaii Island, some about volcano life spans. Three alternative These results, in combination with a vast body data from older islands are referenced briefl y models are compared: (1) near-constant of older data, provide new insights about vol- where helpful to constrain volcano-growth volcano propagation, (2) near-equal volcano cano growth on Hawaii. More prior studies than models. In part, this analysis is a sequel to the durations, (3) high peak-tholeiite magma can be acknowledged have evaluated growth of impressive synthesis by Moore and Clague supply. These models defi ne inconsisten- Hawaii in relation to longer-term evolution of the (1992), while benefi ting from compilations for cies with prior geodynamic models, indicate Hawaiian Ridge. Notable were early recognition the geologic map of Hawaii Island (Wolfe and that composite growth at Hawaii peaked ca. of the southeastward younging of volcanoes Morris, 1996a, 1996b) and the state map of 800–400 ka, and demonstrate a lower cur- and distinction of the parallel Kea and Loa vol- Hawaii (Sherrod et al., 2007). Particularly use- rent rate. Recent age determinations for canic trends (Dana, 1849; Jackson et al., 1972), ful samples, compositional data, and imaging Kilauea and Kohala defi ne a volcano propa- and of course the insights about ocean-island of deep structure have come from the Hawaii gation rate of 8.6 cm/yr that yields plausible volcanism that emerged in the 1960s from the Scientifi c Drilling Project (HSDP; Stolper et al., inception ages for other volcanoes of the Kea plate-tectonic paradigm. Among recent critical 1996, 2009) and ~100 submersible dives and trend. In contrast, a similar propagation rate observations and interpretations are: quantifying bathymetric surveys during JAMSTEC cruises for the less-constrained Loa trend would propagation rates along the Hawaiian-Emperor in 1998–2002 (Takahashi et al., 2002; Robinson require inception of Loihi Seamount in the Ridge by isotopic dating (McDougall and et al., 2003; Coombs et al., 2006a). future and ages that become implausibly Swanson, 1972; Jackson et al., 1972; Clague Reliable age determinations for old Hawaiian large for the older volcanoes. An alternative and Dalrymple, 1987), volume estimates from lavas remain sparse, but recent application of rate of 10.6 cm/yr for Loa-trend volcanoes is submarine bathymetry (Bargar and Jackson, 40Ar/39Ar methods to young basalts, especially Geosphere; October 2013; v. 9; no. 5; p. 1348–1383; doi:10.1130/GES00935.1; 15 fi gures; 11 tables. Received 2 April 2013 ♦ Revision received 6 July 2013 ♦ Accepted 29 July 2013 ♦ Published online 14 August 2013 1348 For permission to copy, contact [email protected] © 2013 Geological Society of America Downloaded from http://pubs.geoscienceworld.org/gsa/geosphere/article-pdf/9/5/1348/3345176/1348.pdf by guest on 30 September 2021 Volcano growth on Hawaii N 21° HA Hana Ridge K A B′ Laupahoehoe Slump M-G KP KO M-C Kiholo R Hilo Ridge MK A′ N Kona Slump B H Figure 7 HU Puna Ridge ML KL MSB N LO 19° 100100 kmkm Ka Lae R 156° 154° Figure 1. Map of the Island of Hawaii and adjacent sea fl oor, showing locations of volcanoes (Kea trend in black; Loa trend in blue): HA—Haleakala; HU—Hualalai; K—Kahoolawe; KL—Kilauea; KO—Kohala; LO—Loihi; M-G—Mahukona (summit location of Garcia et al. [1990]); M-C—Mahukona (summit location of Clague and Moore [1991]); MK—Mauna Kea; ML—Mauna Loa. Historical eruptions are in red. Dashed line is the inferred buried east rift of Kohala that continues into Hilo Ridge. H—Hilo (site of HSDP hole); KP—Kohala platform; MSB—mid-slope bench offshore of Kilauea. Modifi ed from Robinson et al. (2006). Cross sections A–A′ and B–B′ (short dotted lines) are depicted in Figure 6. Arrow at the base of Hilo Ridge is the site of dive K215 (Fig. 7). underwater and subsurface samples, has TABLE 1. RECENT 40Ar/39Ar GEOCHRONOLOGIC RESULTS, ISLAND OF HAWAII improved controls on volcano growth (Table 1). Rock type Alkalic lavas have yielded stratigraphically Volcano (number of ages) References coherent results for Mauna Kea and Kilauea Kilauea Alkalic and transitional basalt (13) Calvert and Lanphere (2006) Transitional basalt (2) Hanyu et al. (2010) (Sharp and Renne, 2005; Calvert and Lanphere, 2006), but dating of low-K tholeiites continues Mauna Loa Tholeiite (1) Sharp et al. (1996) Tholeiite (1) Sharp and Renne (2005) to be problematic because of low radiogenic- Tholeiite (14) Jicha et al. (2012) argon yields. In such tholeiites, K resides Mauna Kea Alkalic and tholeiitic basalt (9) Sharp et al. (1996) mainly in glassy selvages next to groundmass Alkalic and tholeiitic basalt (9) Sharp and Renne (2005) minerals, leaving samples vulnerable to argon Kohala Transitional-alkalic basalt (2) Lipman and Calvert (2011) loss and/or argon-recoil problems in the reactor. Mahukona Transitional and tholeiitic basalt (2) Clague and Calvert (2009) Some tholeiite samples fail to yield meaningful Transitional and tholeiitic basalt (3) Garcia et al. (2012) ages without apparent petrographic or chemi- Note: Ages and analytical data are listed in Appendix A. cal reasons. In the most detailed 40Ar/39Ar study Geosphere, October 2013 1349 Downloaded from http://pubs.geoscienceworld.org/gsa/geosphere/article-pdf/9/5/1348/3345176/1348.pdf by guest on 30 September 2021 Lipman and Calvert to date of Hawaiian tholeiites, on the 1.5 km 100 scarp along the submarine southwest rift zone Robinson & Eakins (2006) of Mauna Loa, only 14 of 45 analyzed samples 3 80 km yielded “successful ages” (Jicha et al., 2012). 3 This review Less precise K-Ar determinations remain the main data for subaerial lavas on Kohala and 60 Mauna Kea, and attempts to improve resolu- tion by unspiked K-Ar methods for Kilauea and Loihi basalts (Guillou et al., 1997a, 1997b) 40 yielded some results that are internally con- tradictory or inconsistent with 40Ar/39Ar dates Total volcano volume, 10 (Calvert and Lanphere, 2006). Appendix A lists 20 the published 40Ar/39Ar and some recent K-Ar age determinations used for estimating volcano growth rates for the Island of Hawaii and under- 0 Mahukona Kohala Hualalai Mauna Mauna Kilauea Loihi water slopes. Kea Loa Volumes of individual volcanoes are also diffi cult to estimate, with probable uncertain- Figure 2. Interpreted volumes of volcanoes, Island of Hawaii: pub- ties of 10%–20%, but constrained by the com- lished (Robinson and Eakins, 2006) and proposed revised values posite island construct (213,000 km3; Robinson (assumption of small Mahukona; Garcia et al., 2012).