Dimitri A. Sverjensky's research while affiliated with Johns Hopkins University and other places
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Publications (162)
Serpentinization is among the most important, and ubiquitous, geological processes in crustal–upper mantle conditions (<6 GPa, <600°C), altering the rheology of rocks and producing H2 that can sustain life. While observations are available to quantify serpentinization in terrestrial and mid‐ocean ridge environments, measurements within subduction z...
Ocean sediments consist mainly of calcium carbonate and organic matter (phytoplankton debris). Once subducted, some carbon is removed from the slab and returns to the atmosphere as CO 2 in arc magmas. Its isotopic signature is thought to reflect the bulk fraction of inorganic (carbonate) and organic (graphitic) carbon in the sedimentary source. Her...
The water-gas shift reaction is one of the most important reactions in industrial hydrogen production and plays a key role in Fischer-Tropsch-type synthesis, which is widely believed to generate hydrocarbons in the deep carbon cycle but is little known at extreme pressure-temperature conditions found in the Earth's upper mantle. Here, we performed...
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The water-gas shift reaction is one of the most important reactions in industrial hydrogen production and plays a key role in Fischer-Tropsch-type synthesis, which is widely believed to generate hydrocarbons in the deep carbon cycle, but is little known at extreme pressure-temperature conditions found in Earth’s upper mantle. Here, we perfor...
Geological sources of H2 and abiotic CH4 have had a critical role in the evolution of our planet and the development of life and sustainability of the deep subsurface biosphere. Yet the origins of these sources are largely unconstrained. Hydration of mantle rocks, or serpentinization, is widely recognized to produce H2 and favour the abiotic genesi...
Diamonds containing fluid inclusions provide invaluable samples of upper mantle fluids, the study of which illuminates not only diamond formation but also the long-term evolution of the subcratonic, lithospheric mantle. The very large range of inclusion compositions worldwide has been interpreted to represent four end-member fluids: saline (rich in...
Decades of research have now firmly established that aqueous fluids in Earth's crust from groundwater to deep basinal brines to shallow mid‐ocean ridge hydrothermal systems can contain metastable equilibria involving C‐species in which methane does not participate. It now appears, however, that this situation does not extend to the upper mantle. In...
Organic matter, showing variable degrees of crystallinity and thus of graphitization, is an important source of carbon in subducted sediments, as demonstrated by the isotopic signatures of deep and ultra-deep diamonds and volcanic emissions in arc settings. In this experimental study, we investigated the dissolution of sp2 hybridized carbon in aque...
Redox states of the Archean Eon have been constrained by various lines of evidence, including atmospheric, photochemical, and ecological models, mass-independent fractionations of sulfur isotopes, Fe-depletion of paleosols, and preservation of diagnostic detrital minerals. Although these lines of evidence present seemingly consistent upper limits o...
Fluids in the deep crust and upper mantle appear to have played roles in the long-term evolution of the subcratonic lithospheric mantle and the stabilities of the continents, in the geochemical cycles of the elements from subduction zones to Earth's surface environment, and in the formation of diamonds. Much evidence of the chemistry of deep fluids...
Carbon is subducted to depths where metamorphism liberates water-bearing fluids. The C-bearing fluids facilitate partial melting of the upper mantle, generating magmas that may erupt as arc volcanics. Degassing of the magmas releases CO 2 and other volatile species to the atmosphere. Over geological time, this process contributes to the composition...
Chromium is mobile in ultramafic magmas but its mobility in high temperature fluids has long been unclear. Studies of some chromium-rich ophiolites have suggested chromium mobility in upper mantle fluids. However, the mechanism is poorly understood because Cr(III) is so insoluble in water. We used previous estimates of aqueous Cr species and publis...
Dissolved ions present in an aqueous environment may significantly improve biomolecule attachment at mineral surfaces through the formation of cooperative surface complexes. To test whether this phenomenon results in the selective adsorption of an organic species, we conducted batch adsorption experiments with an equimolar mixture of the amino acid...
The adsorption of nucleic acid components onto the serpentinite-hosted hydrothermal mineral brucite has been investigated experimentally by determining the equilibrium adsorption isotherms in aqueous solution. Thermodynamic characterization of the adsorption data has been performed using the extended triple-layer model (ETLM) to establish a model f...
The geological cycle of deep, abiotic hydrocarbons on Earth is still barely known. Direct observation of natural abiotic gases is possible at low-pressure conditions at hydrothermal vents, whereas the genesis and evolution of abiotic hydrocarbons at high-pressure conditions relevant to subduction zones is mainly derived from experiments. Last year...
We experimentally investigated the dissolution of forsterite, enstatite and magnesite in graphite-saturated COH fluids, synthesized using a rocking piston cylinder apparatus at pressures from 1.0 to 2.1 GPa and temperatures from 700 to 1200 °C. Synthetic forsterite, enstatite, and nearly pure natural magnesite were used as starting materials. Redox...
The adsorption and concentration of sugars onto mineral surfaces in geochemical environments, such as hydrothermal systems, may have influenced the evolution of early life on Earth. We conducted batch adsorption experiments between D-ribose and brucite [Mg(OH)2], a mineral produced from serpentinite-hosted hydrothermal systems, over variable initia...
Estimates of dissolved CO2 in subduction-zone fluids are based on thermodynamic models, relying on a very sparse experimental data base. Here, we present experimental data at 1–3 GPa, 800 °C, and ∆FMQ ≈ −0.5 for the volatiles and solute contents of graphite-saturated fluids in the systems COH, SiO2–COH ( + quartz/coesite) and MgO–SiO2–COH ( + forst...
Subduction zones facilitate chemical exchanges between Earth's deep interior and volcanism that affects habitability of the surface environment. Lavas erupted at subduction zones are oxidized and release volatile species. These features may reflect a modification of the oxidation state of the sub-arc mantle by hydrous, oxidizing sulfate and/or carb...
In our standard late Archean weathering model (pCO2,g = bars, pH2,g = bars), crustal apatite was totally dissolved by the acidic rainwater during weathering. Our model quantitatively links the pCO2,g of the atmosphere to phosphate levels transported by rivers. The development of late Archean river water (pH = 6.4) resulted in riverine phosphate of...
The cycling of carbon between Earth's surface and interior governs the long-term habitability of the planet. But how carbon migrates in the deep Earth is not well understood. In particular, the potential role of hydrocarbon fluids in the deep carbon cycle has long been controversial. Here we show that immiscible isobutane forms in situ from partial...
Nitrogen is distributed throughout all terrestrial geological reservoirs (i.e., the crust, mantle, and core), which are in a constant state of disequilibrium due to metabolic factors at Earth’s surface, chemical weathering, diffusion, and deep N fluxes imposed by plate tectonics. However, the behavior of nitrogen during subduction is the subject of...
Hydrothermal systems may have been favorable environments for the evolution of prebiotic chemistry on early Earth due to the presence of chemical, temperature, and redox gradients that could promote the formation of biomolecules. However, the relevance of these environments in origins of life scenarios has been debated due to rapid decomposition of...
Interpretations of the geologic record of late Archean near-surface environments depend very strongly on an understanding of weathering and resultant riverine transport to the oceans. The late Archean atmosphere is widely recognized to be anoxic (pO2,g = 10-5 to 10-13 bars; pH2,g = 10-3 to 10-5 bars). Detrital siderite (FeCO3), pyrite (FeS2), and u...
The solubility of carbonate minerals and aqueous carbonate speciation in deep fluids is of critical importance to the long–term carbon cycle. However, no experimental data exist in the calcium carbonate-water-salt system at pressures greater than 10 Kbar. Here we present an integrated experimental and theoretical study of carbon speciation and solu...
Earth's living and non-living components have co-evolved for 4 billion years through numerous positive and negative feedbacks. Earth and life scientists have amassed vast amounts of data in diverse fields related to planetary evolution through deep time-mineralogy and petrology, paleobiology and paleontology, paleotectonics and paleomagnetism, geoc...
Supplementary Figure 1, Supplementary Tables 1-2, Supplementary Note 1 and Supplementary Reference.
Diamond formation has typically been attributed to redox reactions during precipitation from fluids or magmas. Either the oxidation of methane or the reduction of carbon dioxide has been suggested, based on simplistic models of deep fluids consisting of mixtures of dissolved neutral gas molecules without consideration of aqueous ions. The role of p...
The interaction of biomolecules at the mineral-water interface could have played a prominent role in the emergence of more complex organic species in life’s origins. Serpentinite-hosted hydrothermal vents may have acted as a suitable environment for this process to occur, although little is known about biomolecule-mineral interactions in this syste...
The interactions between nucleic acids and mineral surfaces have been the focus of many studies in environmental sciences, in biomedicine, as well as in origin of life studies for the prebiotic formation of biopolymers. However, few studies have focused on a wide range of environmental conditions and the likely modes of attachment. Here we investig...
Four factors contribute to the roles played by chance and necessity in determining mineral distribution and diversity at or near the surfaces of terrestrial planets: (1) crystal chemical characteristics; (2) mineral stability ranges; (3) the probability of occurrence for rare minerals; and (4) stellar and planetary stoichiometries in extrasolar sys...
Supercritical aqueous fluids link subducting plates and the return of carbon to Earth's surface in the deep carbon cycle. The amount of carbon in the fluids and the identities of the dissolved carbon species are not known, which leaves the deep carbon budget poorly constrained. Traditional models, which assume that carbon exists in deep fluids as d...
Decomposition of oxalic acid in the presence of water was examined in a hydrothermal diamond-anvil cell up to 800 °C and 970–1480
MPa as a function of oxygen fugacity to assess its usefulness as a C-O-H fluid source in petrologic experiments. Fluid, vapor,
and solid species were identified in situ at elevated temperature and pressure with Raman spe...
Volatile elements stored in the mantles of terrestrial planets escape through volcanic degassing, and thereby influence planetary atmospheric evolution and habitability. Compared with the atmospheres of Venus and Mars, Earth's atmosphere is nitrogen-rich relative to primordial noble gas concentrations. The compatibility of volatile elements in mant...
Geochemical models for aqueous solution equilibria extend to pressures and temperatures well beyond experimental spectroscopies that could test the predictions. W. H. Casey and co-workers describe in their Communication on page 9788 ff. a simple NMR probe that can allow spectroscopy on solutions at pressures near those of the Earth's continental cr...
Die geochemischen Modelle chemischer Gleichgewichte in wässriger Lösung reichen oft über die zugänglichen Druck- und Temperaturbereiche verfügbarer Spektroskopien hinaus. W. H. Casey et al. beschreiben in der Zuschrift auf S. 9946 ff. nun eine einfache NMR-Sonde, die die spektroskopische Untersuchung von Lösungen bei Drücken ähnlich denen im Innern...
A non-magnetic piston-cylinder pressure cell is presented for solution-state NMR spectroscopy at geochemical pressures. The probe has been calibrated up to 20 kbar using in situ ruby fluorescence and allows for the measurement of pressure dependencies of a wide variety of NMR-active nuclei with as little as 10 μL of sample in a microcoil. Initial (...
A non-magnetic piston-cylinder pressure cell is presented for solution-state NMR spectroscopy at geochemical pressures. The probe has been calibrated up to 20 kbar using in situ ruby fluorescence and allows for the measurement of pressure dependencies of a wide variety of NMR-active nuclei with as little as 10 μL of sample in a microcoil. Initial 1...
The interactions of biomolecules such as amino acids with mineral surfaces in the near-surface environment are an important part of the short and long-term carbon cycles. Amino acid-mineral surface interactions also play an important role in biomineralization, biomedicine, and in assembling the building blocks of life in the prebiotic era. Although...
Natural hydrothermal vent environments cover a wide range of physicochemical conditions involving temperature, pH and redox state. The stability of simple biomolecules such as amino acids in such environments is of interest in various fields of study from the origin of life to the metabolism of microbes at the present day. Numerous previous experim...
Carbonate minerals may be recycled into the mantle at subduction zones. However, the evolution of carbonate minerals in equilibrium with aqueous fluids as well as the nature of the chemical species of dissolved carbon in the deep crust and mantle at high PT conditions are still unknown. In this study, we report an integrated experimental and theore...
Comprehensive quantitative theoretical evaluation of water–rock interactions in the Earth has long been restricted to a pressure of 5.0 kb – too low to address processes involving deep aqueous fluids. Yet such fluids are thought to play an important role in the long-term geologic cycling of many chemical elements. A reason for this restriction is t...
Changes in the mechanisms of formation and global distribution of phyllosilicate clay minerals through 4.567 Ga of planetary
evolution in our solar system reflect evolving tectonic, geochemical, and biological processes. Clay minerals were absent
prior to planetesimal formation ~4.6 billion years ago but today are abundant in all near-surface Earth...
Crystal surfaces provide physical interfaces between the geosphere and biosphere. It follows that the arrangement of atoms at the surfaces of crystals profoundly influences biological components at many levels, from cells through biopolymers to single organic molecules. Many studies have focused on the crystal-molecule interface in water using larg...
Water is a major component of fluids in the Earth's mantle, where its properties are substantially different from those at ambient conditions. At the pressures and temperatures of the mantle, experiments on aqueous fluids are challenging, and several fundamental properties of water are poorly known; e.g., its dielectric constant has not been measur...
Knowledge of the dielectric constant of water as a function of pressure
(P) and temperature (T) plays a critical role in understanding the
chemistry of aqueous systems, and in particular of fluids in the Earth's
mantle. By using ab initio molecular dynamics, we computed the
dielectric constant of water at T = 1000 and 2000 K, between 1 and 12
GPa,...
Temporal trends in Earth's near-surface mineralogy correlate with major events in Earth's geochemical and tectonic history. New and published analyses of 422 molybdenite (MoS2) specimens from 135 localities with known ages from 2.91 billion years (Ga) to 6.3 million years (Ma) reveal two statistically significant trends. First, systematic increases...
Carbon can be a major constituent of crustal and mantle fluids, occurring both as dissolved ionic species (e.g., carbonate ions or organic acids) and molecular species (e.g., CO2, CO, CH4, and more complex organic compounds). The chemistry of dissolved carbon changes dramatically with pressure ( P ) and temperature ( T ). In aqueous fluids at low P...
The discovery of the extreme antiquity of specific minerals through radiometric dating (e.g., Strutt 1910), coupled with Norman L. Bowen’s recognition of a deterministic evolutionary sequence of silicate minerals in igneous rocks (Bowen 1915, 1928), implies that Earth’s crustal mineralogy has changed dramatically through more than 4.5 billion years...
The adsorption configuration of organic molecules on mineral surfaces is of great interest as it can provide fundamental information for both engineered and natural systems. Here we have conducted surface-enhanced Raman spectroscopy (SERS) measurements to probe the attachment configurations of DOPA on nano-rutile particles at different pH and surfa...
Analyses of the temporal and geographic distribution of earliest recorded appearances of the 88 IMA-approved mercury minerals plus two potentially valid species exemplify principles of mineral evolution. Metacinnabar (HgS) and native Hg are the only two species reported from meteorites, specifically, the primitive H3 Tieschitz chondrite with an age...
The adsorption configuration of organic molecules on mineral surfaces is of great interest because it can provide fundamental information for both engineered and natural systems. Here we have conducted surface-enhanced Raman spectroscopy (SERS) measurements to probe the attachment configurations of DOPA on nanorutile particles under different pH an...
Temporal and geographic distribution of 90 known Hg minerals exemplify
principals of mineral evolution. Since the appearance of cinnabar at ~3
Ga, Hg minerals have been present continuously at or near Earth's
surface (Fig.1). Mercury mineral evolution is characterized by episodic
deposition and diversification associated with the supercontinent cyc...
The mineral-water interface governs an extensive range of geochemical
processes on the Earth's surface such as weathering, contaminant
migration, and the adsorption and concentration of organic acids
important in biochemistry. Aqueous silica is a prevalent constituent of
soilwater, groundwater and riverwater, and experiments indicate that it
strong...
Progress in understanding mineral evolution, Earth’s changing near-surface mineralogy through time, depends on the availability
of detailed information on mineral localities of known ages and geologic settings. A comprehensive database including this
information, employing the mindat.org web site as a platform, is now being implemented. This resour...
Dihydroxyphenylalanine (DOPA) and similar molecules are of considerable interest in studies of bioadhesion to minerals, solar cells involving titanium dioxide, and biomedical imaging. However, the extent and mechanisms of DOPA adsorption on oxides in salt solutions are unknown. We report measurements of DOPA adsorption on well-characterized rutile...
Attenuated total reflectance (ATR) Fourier transform infrared (FTIR) spectroscopy and quantum chemical calculations were used to elucidate the influence of solution chemistry (pH, amino acid concentration) on the binding mechanisms of glutamic and aspartic acid to rutile (α-TiO(2)). The amino acids, glutamate and aspartate, contain carboxyl and ami...
Interest in the development of oxide-based materials for arsenate removal has led to a variety of experimental methods and conditions for determining arsenate adsorption isotherms, which hinders comparative evaluation of their adsorptive capacities. Here, we systematically investigate the effects of buffer (HEPES or carbonate), adsorbent dose, and...
Mineral evolution explores changes through time in Earth's near-surface mineralogy, including diversity of species, relative abundances of species, and compositional ranges of major, minor and trace elements. Such studies elucidate the co-evolution of the geosphere and biosphere. Accordingly, we investigated trace and minor elements in molybdenite...
The abiotic polymerization of amino acids may have been important for the origin of life, as peptides may have been components of the first self-replicating systems. Though amino acid concentrations in the primitive oceans may have been too dilute for significant oligomerization to occur, mineral surface adsorption may have provided a concentration...
Crystalline surfaces of common rock-forming minerals are likely to have played several important roles in life's geochemical origins. Transition metal sulfides and oxides promote a variety of organic reactions, including nitrogen reduction, hydroformylation, amination, and Fischer-Tropsch-type synthesis. Fine-grained clay minerals and hydroxides fa...
The current study is focused on surface interactions between L-arginine, the most basic protein amino acid, and rutile in NaCl media over a wide range of solution pH conditions, amino acid concentrations, and solution ionic strengths.
Interactions between aqueous amino acids and mineral surfaces influence many geochemical processes from biomineralization to the origin of life. However, the specific reactions involved and the attachment mechanisms are mostly unknown. We have studied the adsorption of l-aspartate on the surface of rutile (α-TiO2, pHPPZC = 5.4) in NaCl(aq) over a w...
Nucleic acids, the storage molecules of genetic information, are composed of repeating polymers of ribonucleotides (in RNA) or deoxyribonucleotides (in DNA), which are themselves composed of a phosphate moiety, a sugar moiety, and a nitrogenous base. The interactions between these components and mineral surfaces are important because there is a tre...
This study enables a better understanding of molecular level interactions between biological molecules and biomaterials such as titanium implants and may also be of importance for understanding the role of mineral-surface interactions in the origin of life.
Before the Great Oxidation Event (GOE), at ∼2.4 Ga, the mineralogical record of the near-surface continental environment indicates a low partial pressure of oxygen during weathering, which restricted many elements to a low oxidation state and limited the number of possible minerals formed from these elements. Calculations show that local pulses in...
Citations
... the inclusions from subsequent metasomatic events. There are alternative opinions stating that inclusions in diamonds are protogenetic and do not represent the diamond crystallization environment (Rinaldi et al., 2023). However, comparisons between eclogitic inclusions and the corresponding minerals in the matrix of xenoliths unambiguously identify a trend to enrichment by kimberlite-like melt (e.g. ...
Reference: Allanite in Mantle Eclogite Xenoliths
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... Additionally, CH 4 has been found in high-pressure and ultra-high-pressure rocks (Tao et al., 2018;Wang et al., 2022;Zhu et al., 2020). Experimental and theoretical studies have demonstrated that H 2 and light hydrocarbons can be immiscible at subduction zone conditions (Huang et al., 2017;Huang et al., 2023;Li, 2017;Pruteanu et al., 2017). However, the generation of reduced-carbon species in subduction zone fluids or as immiscible phases has not received much attention. ...
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... Carbon is ubiquitous in geologic fluids, e.g., in hydrocarbon-rich fluids, as small fractions in aqueous fluids or dominant in CO 2 -rich systems (Connolly and Cesare, 1993;Huang et al., 2017;Kokh et al., 2017). Carbon isotope geochemistry has long been used to track sources and processes in geologic systems (Baumgartner and Valley, 2001;Bebout and Fogel, 1992;Duke and Rumble, 1986;Kitchen and Valley, 1995;Luque et al., 2012;Mason et al., 2017;Ray, 2009;Ray and Ramesh, 2000;Stachel et al., 2017;Tumiati et al., 2022;Valley, 1986). ...
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... To date, natural CH 4 -H 2 fluid inclusions in the ophicarbonates in metamorphosed ultramafic rocks have demonstrated the existence of hydrocarbon fluids at upper mantle conditions [1]. Experimental studies of the disproportionation reaction of 0.5 M Ca-acetate solution at 300°C and 1.6 -4.6 GPa have documented the formation of immiscible hydrocarbon fluid containing methane, ethane, propane, and isobutane coexisting with aqueous HCO 3 and CO 3 2-, and aragonite or calcite minerals [2]. ...
... Our short account starts closing this gap by providing surprising molecular insights into the solvation properties of neutral gold species in water at supercritical conditions. Although a wealth of supercritical and hydrothermal aqueous solutions have been studied at the molecular level [19][20][21][22][23][24][25][26][27][28][29] using ab initio molecular dynamics (AIMD), [30] providing access to not only structural dynamics but also to electronic properties, the same is not true for gold clusters in SCW. [31] For individual gold atoms in ambient liquid water, Au(aq), a Janus-type solvation shell around charge-neutral gold species has been found to contain a single hydration water molecule on average with either the water-H or water-O atoms pointing towards the gold atom-respectively, corresponding to typical anionic or cationic solvation patterns. ...
... This does not necessarily mean that these diamonds formed at great depths, ascending through the mantle in a plume and then grew again at shallower depths through different processes and under different conditions. The observed chemical disequilibrium may rather reflect progressive chemical mass transfer during a reaction between a fluid released by a deeply subducted mafic slab with ambient peridotite [35,38]. ...
... Many fewer studies have been concerned with hydrocarbon production during high-pressure metamorphism in subduction zones, where most studies have typically focused on oxidized carbon species dissolved in the fluid phases (Dasgupta and Hirschmann, 2010;Hacker et al., 2003;Scambelluri et al., 2019). Subduction zone serpentinization has been proposed to produce large amounts of H 2 and CH 4 (Boutier et al., 2023;Vitale Brovarone et al., 2020). Additionally, CH 4 has been found in high-pressure and ultra-high-pressure rocks (Tao et al., 2018;Wang et al., 2022;Zhu et al., 2020). ...
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... The geochemistry of fluid inclusions in diamonds reveals four compositional groups: silicic, peridotitic, carbonatitic and saline (Navon et al., 1988;Izraeli et al., 2001;Tomlinson et al., 2006;Weiss et al., 2009Weiss et al., , 2014Weiss et al., , 2022Timmerman et al., 2021) (Fig. 1a). The origin of diamond-forming fluids has been examined by experimental (e. g., Kessel et al., 2015;Bureau et al., 2018;Förster et al., 2019;Sonin et al., 2022;Meltzer and Kessel, 2022) and theoretical approaches (Huang and Sverjensky, 2020;Mikhail et al., 2021), alongside studies predicting the geochemistry of diamond-forming fluids which would be in equilibrium with solid silicate inclusions (e.g., Stachel and Harris, 2008;Aulbach et al., 2008;Mikhail et al., 2019a). ...
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... Nevertheless, natural confirmation of immiscible, CH 4 -H 2 -bearing fluids related to serpentinization in subduction zones have now been found world-wide. For example, coexisting aqueous and CH 4 − H 2 -rich gaseous fluid inclusions in the Lanzo massif, western Italian Alps (Giuntoli et al., 2020;Pelletier and Müntener, 2006;Sverjensky et al., 2020;Vitale Brovarone et al., 2017 have been suggested to document immiscibility of reduced fluids in metamorphic fluids. In these rocks, CH 4 formed by H 2 -mediated reduction of carbonate in carbonated serpentinites. ...
... Although there is a diversity of opinions about how the various types of graphite have formed-varying from precipitation from mantle liquids to metamorphic reactions in coal seams (Simandl et al., 2015), the uncertainty of formation is no less for diamonds (Smit and Shirey, 2018). Regrettably, in experimental work on mantle processes (Hayes and Waldbauer, 2006;Tumiati et al., 2020), it is usually taken for granted that the high pressures necessary for diamond formation are achieved by deep subduction, and Tappert et al. (2005) concluded that diamond was formed by direct transformation of graphite with increasing pressure through subduction. No one seems to care that none of the basic plate tectonic mechanisms and principles have been verified. ...
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