Match!

Constraining the source of mantle plumes

Published on Feb 1, 2016in Earth and Planetary Science Letters4.637
· DOI :10.1016/J.EPSL.2015.12.008
Neil Cagney7
Estimated H-index: 7
(UCL: University College London),
Fabio Crameri8
Estimated H-index: 8
(UCL: University College London)
+ 4 AuthorsJohn Whitehead54
Estimated H-index: 54
(WHOI: Woods Hole Oceanographic Institution)
Abstract
Abstract In order to link the geochemical signature of hot spot basalts to Earth's deep interior, it is first necessary to understand how plumes sample different regions of the mantle. Here, we investigate the relative amounts of deep and shallow mantle material that are entrained by an ascending plume and constrain its source region. The plumes are generated in a viscous syrup using an isolated heater for a range of Rayleigh numbers. The velocity fields are measured using stereoscopic Particle-Image Velocimetry, and the concept of the ‘vortex ring bubble’ is used to provide an objective definition of the plume geometry. Using this plume geometry, the plume composition can be analysed in terms of the proportion of material that has been entrained from different depths. We show that the plume composition can be well described using a simple empirical relationship, which depends only on a single parameter, the sampling coefficient, s c . High- s c plumes are composed of material which originated from very deep in the fluid domain, while low- s c plumes contain material entrained from a range of depths. The analysis is also used to show that the geometry of the plume can be described using a similarity solution, in agreement with previous studies. Finally, numerical simulations are used to vary both the Rayleigh number and viscosity contrast independently. The simulations allow us to predict the value of the sampling coefficient for mantle plumes; we find that as a plume reaches the lithosphere, 90% of its composition has been derived from the lowermost 260–750 km in the mantle, and negligible amounts are derived from the shallow half of the lower mantle. This result implies that isotope geochemistry cannot provide direct information about this unsampled region, and that the various known geochemical reservoirs must lie in the deepest few hundred kilometres of the mantle.
  • References (38)
  • Citations (6)
📖 Papers frequently viewed together
56 Citations
1990
8 Citations
78% of Scinapse members use related papers. After signing in, all features are FREE.
References38
Newest
The three-dimensional velocity and temperature fields surrounding an isolated thermal plume in a fluid with temperature-dependent viscosity are measured using Particle-Image Velocimetry and thermochromatic liquid crystals, respectively. The experimental conditions are relevant to a plume rising through the mantle. It is shown that while the velocity and the isotherm surrounding the plume can be used to visualize the plume, they do not reveal the finer details of its structure. However, by comput...
7 CitationsSource
Typical fluid particle trajectories are sensitive to changes in their initial conditions. This makes the assessment of flow models and observations from individual tracer samples unreliable. Behind complex and sensitive tracer patterns, however, there exists a robust skeleton of material surfaces, Lagrangian coherent structures (LCSs), shaping those patterns. Free from the uncertainties of single trajectories, LCSs frame, quantify, and even forecast key aspects of material transport. Several dia...
379 CitationsSource
Erupting magma often contains crystals over a wide range of sizes and shapes, potentially affecting magma viscosity over many orders of magnitude. A robust relation between viscosity and the modality of crystal sizes and shapes remains lacking, principally because of the dimensional complexity and size of the governing parameter space. We have performed a suite of shear viscosity measurements on liquid-particle suspensions of dynamical similarity to crystal-bearing magma. Our experiments encompa...
66 CitationsSource
3 CitationsSource
#1Albrecht W. Hofmann (MPG: Max Planck Society)H-Index: 78
#2Cinzia G. Farnetani (IPGP: Institut de Physique du Globe de Paris)H-Index: 10
] Fundamentally contradictory interpretations of the isotopic compositions of Hawaiian basalts persist,even among authors who agree that the Hawaiian hotspot is caused by a deep-mantle plume. One viewholds that the regional isotopic pattern of the volcanoes reflects large-scale heterogeneities in the basalthermal boundary layer of the mantle. These are drawn into the rising plume conduit, where they arevertically stretched and ultimately sampled by volcanoes. The alternative view is that the plum...
25 CitationsSource
#1M. A. KhanH-Index: 1
Free air and isostatic gravity anomalies for the purposes of geophysical interpretation are presented. Evidence for the existance of hotspots in the mantle is reviewed. The prosposed locations of these hotspots are not always associated with positive gravity anomalies. Theoretical analysis based on simplified flow models for the plumes indicates that unless the frictional viscosities are several orders of magnitude smaller than the present estimates of mantle viscosity or alternately, the vertic...
38 Citations
#1John Whitehead (WHOI: Woods Hole Oceanographic Institution)H-Index: 54
#2Aline Cotel (UM: University of Michigan)H-Index: 7
Last. William H. Newsome (UM: University of Michigan)H-Index: 3
view all 5 authors...
8 CitationsSource
#1Maxim D. Ballmer (ETH Zurich)H-Index: 16
#2Garrett Ito (UH: University of Hawaii)H-Index: 33
Last. Paul J. Tackley (ETH Zurich)H-Index: 54
view all 4 authors...
be explained by the classical mantle plume concept. Here we present a numerical model of mantle plume upwelling beneath Hawaii. We find that small-scale convection in the ambient mantle can erode the base of the lithosphere, creating a washboard topography on the underside of the plate. As the plate migrates over the upwelling plume, the plume interacts with alternating thicker and thinner sections of lithosphere to generate temporal variations in the flux of erupted volcanic material. The pre-e...
75 CitationsSource
#1Anne Davaille (CNRS: Centre national de la recherche scientifique)H-Index: 27
#2Angela Limare (IPG Photonics)H-Index: 12
Last. Judith Vatteville (IPG Photonics)H-Index: 3
view all 5 authors...
We present an experimental study of the dynamics of a plume generated from a small heat source in a high Prandtl number fluid with a strongly temperature-dependent viscosity. The velocity field was determined with particle image velocimetry, while the temperature field was measured using differential interferometry and thermochromic liquid crystals. The combination of these different techniques run simultaneously allows us to identify the different stages of plume development, and to compare the...
25 CitationsSource
Mantle plumes—which are usually, but not always, chemically distinct from the mid-ocean ridge basalt (MORB)—may be rooted in the core-mantle boundary and begin with large voluminous heads triggering massive eruptions or be headless and arise in the mid-mantle. Geochemistry provides convincing evidence that mantle plumes are 100–300°C hotter than normal upper mantle and that upwelling rates within the melting region are faster than beneath mid-ocean ridges. 186Os/188Os hints at the possibility of...
134 CitationsSource
Cited By6
Newest
#1Zezhong Zhang (Northwest University (United States))H-Index: 3
#2Jiangfeng Qin (Northwest University (United States))H-Index: 16
Last. Fangyi Zhang (Northwest University (United States))H-Index: 3
view all 8 authors...
Abstract Contemporaneous alkaline and gabbroic intrusions are commonly observed around high-Ti basalt in the inner zone of Emeishan large igneous province (ELIP), the distribution and origin of these igneous rocks are significant to understand the process associated with a head of Emeishan mantle plume activity. In this study, we present detailed petrology, chronology, major and trace element geochemistry, whole rock Sr-Nd isotopes and zircon Hf isotopes for quartz syenite and hornblende gabbro ...
Source
#1César NavarreteH-Index: 7
#2Guido M. Gianni (CONICET: National Scientific and Technical Research Council)H-Index: 13
Last. Andrés Folguera (CONICET: National Scientific and Technical Research Council)H-Index: 29
view all 7 authors...
Abstract A novel geodynamic evolution model of the southwestern region of Gondwana from the late Triassic to the middle Jurassic period is proposed in this contribution, based on new data collected in the Patagonian region and an exhaustive bibliographic review. New geochemical data of La Leona Fm. (Deseado Massif) and a new zircon U/Pb age (207.6 + 4.1/−2.3 Ma), added to a compilation of previous geochronological and geochemical data, allow confirming the existence of an Upper Triassic magmatic...
15 CitationsSource
#1J.G. Shellnutt (NTNU: National Taiwan Normal University)H-Index: 1
#2K. R. HariH-Index: 4
Last. S.D. DeshmukhH-Index: 1
view all 6 authors...
Abstract The NNW trending tholeiitic Sonakhan mafic dyke swarm of the Northern Bastar Craton is comprised of basalt to basaltic andesite (SiO2 = 46.3 wt% to 55.3 wt%; Mg# = 37 to 70) dykes. A single basaltic dyke yielded a weighted-mean 207Pb/206Pb baddeleyite age of 1851.1 ± 2.6 Ma. The Sr and Nd isotopes (87Sr/86Sri = 0.70396 to 0.70855; eNd(t) = −5.7 to +2.0) are variable which is a consequence of crustal contamination. Trace element modeling suggests the dykes were likely derived by partial ...
4 CitationsSource
#1I. O. Sboev (PSU: Perm State University)H-Index: 2
#2A. N. Kondrashov (PSU: Perm State University)H-Index: 2
Last. M. M. Goncharov (PSU: Perm State University)H-Index: 1
view all 5 authors...
The work presents results of numerical simulations of natural convection in cavity formed by the surfaces of two horizontal coaxial cylinders. The temperature of the outer cylinder is constant. The area between the cylinders is filled with an ideal incompressible fluid. The inner cylinder is set as the heater. The solution of the equations of thermal convection in a two-dimensional approximation performed by the software package ANSYS Fluent with finite volume method. The study compares the resu...
2 CitationsSource
#1Angelo PeccerilloH-Index: 43
The Sicily Province consists of tholeiitic to Na-alkaline magmas that show OIB-type major and trace element features. Except for Pantelleria, compositions are prevailingly mafic. At Etna (0.5 Ma to Present), early-erupted tholeiitic basalts were followed by Na-alkaline hawaiites to trachytes; hawaiitic magmas are presently erupted from central and parasitic vents. Iblei magmatism (7–1.5 Ma) consists of an association of tholeiitic basalts-basaltic andesites and Na-alkaline basalts and nephelinit...
Source
Subduction initiation is a key in understanding the dynamic evolution of the Earth and its fundamental difference to all other rocky planetary bodies in our solar system. Despite recent progress, the question about how a stiff, mostly stagnant planetary lid can break and become part in the global overturn of the mantle is still unresolved. Many mechanisms, externally or internally driven, are proposed in previous studies. Here, we present the results on subduction initiation obtained by dynamica...
14 CitationsSource