Effect of time-evolving age and convergence rate of the subducting plate on the Cenozoic adakites and boninites
Introduction
Arc magmatism in subduction zones is a manifestation of complex physical and chemical processes in the subducting slab, mantle wedge, and overlying crust. Because subduction is a transient process, arc magmatism in subduction zones also exhibits transient behaviors, such as across-arc migration of volcanism and variation in magmatic rock types through space and time (e.g., Kay et al., 2005, Kelemen et al., 2003, Straub and Zellmer, 2012).
Most arc magmatism is thought to result from partial melting of the mantle wedge triggered by the influx/addition of volatiles released from the subducting slab. However, some volcanic rocks are thought to originate from partial melting of the eclogitized oceanic crust of the subducting slab (Defant and Drummond, 1990, Kay, 1978). Typical examples include the well-known adakites in the Aleutians (Defant and Drummond, 1990, Kay, 1978, Stern and Kilian, 1996), bajaites in Baja California (Rogers et al., 1985, Saunders et al., 1987), and sanukitoids in southwest Japan (Koto, 1916, Stern et al., 1989, Tatsumi and Ishizaka, 1981), named after the region where the rocks were discovered. For convenience, we hereafter call the rock ‘adakite’ if it originated from partial melting of subducting oceanic crust. Additionally, the boninites in the Bonin Islands (Cameron et al., 1979, Kuroda et al., 1978) are thought to be attributable to mixing between partial melts from the mantle wedge and eclogitized oceanic crust. Because a cold subducting slab is unlikely to undergo partial melting, unusual tectonic environments such as subduction zones with a very young subducting slab (<25 Ma), ridge subduction, or flat subduction are generally proposed as sites of adakite genesis (Defant and Drummond, 1990, Gutscher et al., 2000, Kay, 1978, Maruyama et al., 1996, Peacock, 1996). Additionally, recent studies have indicated that plume-slab interaction, cold plumes, and the injection of hot asthenospheric mantle into the corner of the mantle wedge are responsible for the partial melting of oceanic crust (Gerya and Yuen, 2003, Kincaid et al., 2013, Lee and Ryu, in press, Yamamoto and Hoang, 2009).
Recent studies have shown that some ‘adakite-like’ rocks are geochemically similar to adakites but are not produced by the partial melting of subducting oceanic crust (e.g., Chung et al., 2003, Gerya and Yuen, 2003, Guan et al., 2012, Kay and Kay, 1993, Lai and Qin, 2013, Richards and Kerrich, 2007). These studies suggested that such adakite-like rocks could be generated in a variety of tectonic environments: partial melting of relaminated oceanic plate in the mantle wedge, crystal fractionation of basaltic magma, and partial melting of thickened mafic lower crust or delaminated lower crust in the intracontinental region. Castillo (2012) distinguished between adakites and adakitic rocks: adakites are characterized by lower 143Nd/144Nd ratios and higher 87Sr/86Sr compared with adakite-like rocks. Hereafter we use the term ‘adakitic rock’ if the rock originated from processes other than partial melting of subducting oceanic crust but has geochemistry similar to that of adakite.
Adakites and boninites have been recovered in the Izu–Bonin–Mariana, Northeast Japan, and Tonga subduction zones, where partial melting of subducting oceanic crust is not expected from the current slab age and convergence rate (e.g., Defant and Drummond, 1990, Gutscher et al., 2000, Peacock, 1996). Therefore, other mechanisms for partial melting of oceanic crust have been suggested to explain these adakites or boninites. In the Izu–Bonin–Mariana subduction zone, previous studies have suggested that Early Eocene boninites were generated by forearc extension during the subduction initiation or by a hot mantle plume (Pearce et al., 1992, Stern and Bloomer, 1992). The adakites in Northeast Japan were generated by the effect of the back-arc opening of the East (Japan) Sea (Yamamoto and Hoang, 2009), and the origin of Tonga boninites is deeply related to back-arc spreading in the Lau Basin (Cooper et al., 2010).
However, the mechanisms described above are only possible explanations for the existence of adakites or boninites. Additionally, the time-evolving slab age and convergence rate constrained from plate reconstruction models, which were not incorporated in previous studies, may play crucial roles in the genesis of adakites or boninites. For example, numerical modeling experiments by Lee and King (2010) revealed that the time-evolving age and convergence rate of the subducting plate are responsible for localized occurrences of adakites in the Western Aleutians. Plate reconstruction models (Sdrolias and Müller, 2006) have revealed that convergence rate and slab age have changed greatly over time even in the same subduction zone, which suggested that past arc volcanism is a consequence of past subduction environments, affected by past slab age and convergence rate rather than current slab age and convergence rate. Thus, time-evolving numerical model experiments are necessary to clarify arc magmatism. Despite the importance of these subduction parameters, many steady-state numerical model experiments use the constant slab age and convergence rate to infer the past arc magmatism (e.g., Baitsch-Ghirardello et al., 2014, Peacock, 1996, Syracuse and Abers, 2006, van Keken et al., 2002).
In our study, we formulated a series of two-dimensional numerical model experiments including time-evolving age and convergence rate of the subducting oceanic plate that are constrained by recent plate reconstruction models (Sdrolias and Müller, 2006) to investigate the transient partial melting of the oceanic crust in the Izu–Bonin, Mariana, Northeast Japan, Kuril, Tonga, Java–Sunda, and Aleutian subduction zones (Fig. 1). Other subduction zones, such as the Cascadia, southwest Japan, and southern Chile are not considered in this study because a very young subducting slab, ridge subduction and/or flat subduction are the likely causes of the partial melting of oceanic crust in the subduction zones. The next sections compare these model calculations with the results of geochemical and petrological studies, and discuss possible reasons for inconsistencies.
Section snippets
Numerical model
To examine the partial melting of oceanic crust, a series of two-dimensional time-dependent subduction models were formulated for the Izu–Bonin, Mariana, Northeast Japan, Kuril, Tonga, Java–Sunda and Aleutian subduction zones. Because most of the numerical experiments conducted in this study are based on previous studies (Lee and King, 2009, Lee and King, 2010), the scheme and rheology used in the experiments are introduced only briefly here. Time-evolving slab age and convergence rate were
Izu–Bonin–Mariana (IBM)
Fig. 3 presents the time-dependent variations of slab age and convergence rate used in our numerical model calculations (Fig. 3b and c) and the resultant time-dependent evolutions of slab surface temperature (Fig. 3d and e) since 50 Ma calculated for the Izu–Bonin and Mariana subduction zones.
According to our models, in the Izu–Bonin subduction zone (Fig. 3d), slab surface temperature was beyond both the solidi of wet sediments (Nichols et al., 1994) and wet basalt (Kessel et al., 2005, Schmidt
Implications of time-evolving subduction parameters to thermal structure
We conducted a series of two-dimensional numerical subduction model experiments to evaluate whether the partial melting of subducting oceanic crust inferred from adakites and boninites can be correlated with the time-evolving subduction parameters. Our model calculations revealed that the time-evolving age and convergence rate of the subducting oceanic plates could explain the transient adakites and boninites in the Izu–Bonin and Western Aleutians.
To clarify the differences between the
Summary
We formulated a series of two-dimensional numerical subduction models using the time-evolving age and convergence rate of the incoming oceanic plate to understand the genesis of adakites and boninites in the IBM, Northeast Japan, Kuril, Tonga, Java–Sunda, and Aleutian subduction zones. Our model calculations successfully explained the adakites and boninites in the Izu–Bonin and Aleutian subduction zones, which cannot be explained by steady-state subduction models using current slab age and
Acknowledgements
We thank to an anonymous reviewer and Prof. Ikuko Wada for their careful reviews, which significantly improved our manuscript. Yoon-Mi Kim (MEST, 2009-0092790) and Changyeol Lee (NRF-35B-2011-1-C00043) are supported by the Ministry of Education, Science and Technology of Korea Government.
References (85)
- et al.
Geodynamic regimes of intra-oceanic subduction: implications for arc extension vs. shortening processes
Gondwana Res.
(2014) Adakite petrogenesis
Lithos
(2012)- et al.
North Tongan high-Ca boninite petrogenesis: the role of Samoan plume and subduction zone-transform fault transition
J. Geodyn.
(1995) - et al.
The petrogenesis of high-calcium boninite lavas dredged from the northern Tonga ridge
Earth Planet. Sci. Lett.
(1991) - et al.
Rayleigh–Taylor instabilities from hydration and melting propel ‘cold plumes’ at subduction zones
Earth Planet. Sci. Lett.
(2003) - et al.
Overriding plate controls spatial distribution of megathrust earthquakes in the Sunda-Andaman subduction zone
Earth Planet. Sci. Lett.
(2006) - et al.
Crustal thickening prior to 38 Ma in southern Tibet: evidence from lower crust-derived adakitic magmatism in the Gangdese Batholith
Gondwana Res.
(2012) - et al.
Catastrophic initiation of subduction following forced convergence across fracture zones
Earth Planet. Sci. Lett.
(2003) - et al.
Hf–Nd isotope and trace element constraints on subduction inputs at island arcs: limitations of Hf anomalies as sediment input indicators
Earth Planet. Sci. Lett.
(2011) - et al.
Small-scale convection under the back-arc occurring in the low viscosity wedge
Earth Planet. Sci. Lett.
(2003)
Origin of adakitic intrusives generated during mid-Miocene east–west extension in southern Tibet
Earth Planet. Sci. Lett.
Early stages in the evolution of Izu-Bonin arc volcanism: new age, chemical, and isotopic constraints
Earth Planet. Sci. Lett.
Aleutian magnesian andesites: melts from subducted Pacific ocean crust
J. Volcanol. Geoth. Res.
Delamination and delamination magmatism
Tectonophysics
The water-basalt system at 4 to 6 GPa: phase relations and second critical endpoint in a K-free eclogite at 700 to 1400 C
Earth Planet. Sci. Lett.
Vectorizing a finite element code for incompressible two-dimensional convection in the Earth’s mantle
Phys. Earth Planet. Inter.
Migration of igneous activities related to ridge subduction in Southwest Japan and the East Asian continental margin from the Mesozoic to the Paleogene
Tectonophysics
Possible manifestations of slab window magmatisms in Cretaceous southwest Japan
Tectonophysics
Adakitic rocks derived from the partial melting of subducted continental crust: evidence from the Eocene volcanic rocks in the northern Qiangtang block
Gondwana Res.
Dynamic buckling of subducting slabs reconciles geological and geophysical observations
Earth Planet. Sci. Lett.
Short-term and localized plume-slab interaction explains the genesis of Abukuma adakite in Northeastern Japan
Earth Planet. Sci. Lett.
Ambient and excess mantle temperatures, olivine thermometry, and active vs. passive upwelling
Chem. Geol.
Geochemistry of Cenozoic volcanic rocks, Baja California, Mexico: implications for the petrogenesis of post-subduction magmas
J. Volcanol. Geoth. Res.
Experimentally based water budgets for dehydrating slabs and consequences for arc magma generation
Earth Planet. Sci. Lett.
Volcanic arcs as archives of plate tectonic change
Gondwana Res.
Existence of andesitic primary magma: an example from southwest Japan
Earth Planet. Sci. Lett.
Opening of the Sea of Japan back-arc basin by asthenospheric injection
Tectonophysics
Sunda-Java trench kinematics, slab window formation and overriding plate deformation since the Cretaceous
Earth Planet. Sci. Lett.
Synchronous Japan Sea opening Miocene fore-arc volcanism in the Abukuma Mountains, NE Japan: an advancing hot asthenosphere flow versus Pacific slab melting
Lithos
Slab melting in the Aleutians: implications of an ion probe study of clinopyroxene in primitive adakite and basalt
Earth Planet. Sci. Lett.
Calculation of peridotite partial melting from thermodynamic models of minerals and melts, IV. Adiabatic decompression and the composition and mean properties of mid-ocean ridge basalts
J. Petrol.
The importance of water to oceanic mantle melting regimes
Nature
Mineralogy, geochemistry and petrogenesis of Kurile island-arc basalts
Contrib. Miner. Petrol.
Geochemical characteristics of boninite- and tholeiite-series volcanic rocks from the Mariana forearc and the role of an incompatible element-enriched fluid in arc petrogenesis
Geol. Soc. Am. Spec. Pap.
Seismic evidence for widespread serpentinized forearc upper mantle along the Cascadia margin
Geology
Boninites, komatiites and ophiolitic basalts
Nature
An overview of adakite petrogenesis
Chin. Sci. Bull.
Adakites from continental collision zones: melting of thickened lower crust beneath southern Tibet
Geology
High-Ca boninites from the active Tonga Arc
J. Geophys. Res.: Solid Earth
Classification, petrogenesis and tectonic setting of boninites
The compositions of anhydrous and H2O-under-saturated melts in equilibrium with refractory peridotites at 15 and 20 Kb: implications for high-Ca boninite petrogenesis
Mineral. Mag.
Cited by (5)
Intracontinental mantle plume and its implications for the Cretaceous tectonic history of East Asia
2017, Earth and Planetary Science LettersCitation Excerpt :Then, we discuss how the intracontinental mantle plume during the Cretaceous was correlated with the various types of intracontinental magmatic and tectonic activities in eastern China. Previous studies show that the time-evolving convergence rate and age of the subducting slab significantly affect the thermal structures of the subducting slab (Kim and Lee, 2014; Lee and Lim, 2014). Thus, we consider the time-evolving subduction parameters estimated from the plate reconstruction models (Sdrolias and Müller, 2006) depicted by the GPlates software (Gurnis et al., 2012).
Effects of temporal plume-slab interaction on the partial melting of the subducted oceanic crust
2015, Journal of Asian Earth SciencesCitation Excerpt :A stress-free boundary condition was implemented along the boundaries enclosing the back-arc mantle and it allowed dynamic mantle inflow/outflow for the mantle wedge. To consider the buoyant serpentinites, the mantle flow at the corner of the mantle wedge is isolated, which was considered in our previous studies (Kim and Lee, 2014; Lee and Lim, 2014). Radiogenic heat productions of 3.80 × 10−11 W/kg for the upper crust and 7.38 × 10−12 W/kg elsewhere were used (Turcotte and Schubert, 2002).
Initiation of adakite occurrence in Cretaceous arc, Northeast Asia
2018, Geosciences Journal