ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    facet.materialart.
    Unknown
    Na-Ca carbonates synthesized under upper-mantle conditions: Raman spectroscopic and X-ray diffraction studies (2015)
    Schweizerbart
    Details
    Publication Date: 2015-03-27
    Description: The new Na 4 Ca(CO 3 ) 3 , Na 2 Ca 3 (CO 3 ) 4 and Na 2 Ca 4 (CO 3 ) 5 compounds were synthesized in the system Na 2 CO 3 –CaCO 3 in multianvil experiments at 6 GPa and characterized by Raman spectroscopy. In addition, the Na 2 Ca 3 (CO 3 ) 4 compound was studied using in situ energy dispersive and single-crystal X-ray diffraction. Single bands in the CO 3 2– symmetric stretching region ( v 1 ) and out-of-plane bending region ( v 2 ) in the Na 4 Ca(CO 3 ) 3 Raman spectrum suggest a single crystallographically distinct carbonate group in the structure. In contrast, the spectra of Na 2 Ca 3 (CO 3 ) 4 and Na 2 Ca 4 (CO 3 ) 5 show two and three bands, respectively, in both the symmetric stretching region ( v 1 ) and out-of-plane bending region ( v 2 ), suggesting more than one crystallographically distinct carbonate group in the unit cell. Raman activity in the forbidden v 2 mode and multiple bands are observed in the in-plane bending region ( v 4 ) for the three compounds, proving the reduction of site symmetry of the CO 3 2– ions with the loss of the threefold rotation axis ( D 3h -〉 D 2h or C s ). Such a decrease in symmetry suggests distortion of the group itself, but may be attained by rearrangements of the coordinated metal cations as in the aragonite-group carbonates. At 6.5 GPa and 1000°C, the structure of Na 2 Ca 3 (CO 3 ) 4 was found to be orthorhombic or monoclinic with a β angle close to 90° and the lattice parameters: a = 7.3357(6) Å, b = 8.0377(9) Å, and c = 31.5322 (32) Å, with V = 929.59(14) Å 3 . No structural changes were observed during pressure decrease down to 1 GPa, while a discontinuous increase in unit-cell parameters and volume was observed upon decompression from 1 GPa at room temperature. This indicates a pressure-induced phase transition to a structurally related ambient-pressure phase. The abnormally long c -parameter and proximity of the β-angle to 90° of Na 2 Ca 3 (CO 3 ) 4 at ambient conditions suggest that, in the monoclinic system, the metric symmetry is higher than the Laue symmetry, which is a common sign for merohedral twinning.
    Print ISSN: 0935-1221
    Electronic ISSN: 1617-4011
    Topics: Geosciences
    Published by Schweizerbart
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 2
    facet.materialart.
    Unknown
    Phase relations on the K2CO3-CaCO3-MgCO3 join at 6 GPa and 900-1400 {degrees}C: Implications for incipient melting in carbonated mantle domains (2016)
    Mineralogical Society of America
    Details
    Publication Date: 2016-02-03
    Description: To constrain the ternary K 2 CO 3 -CaCO 3 -MgCO 3 T-X diagram at 6 GPa and to expand upon the known K-Mg, K-Ca, and Ca-Mg binary systems we have carried out multi-anvil experiments along the K 2 CO 3 -Ca 0.5 Mg 0.5 CO 3 join. The diagram has primary phase fields for K 2 CO 3 , K 2 Mg(CO 3 ) 2 , K 2 Ca 0.1–0.5 Mg 0.9–0.5 (CO 3 ) 2 , K 4 CaMg(CO 3 ) 4 , Ca-magnesite, and dolomite. The system has two liquidus minima near 1000 °C. At one minimum, a liquid with the composition of 36 K 2 CO 3 ·64(Ca 0.65 Mg 0.35 )CO 3 is in equilibrium with three phases: Ca-magnesite, K 2 Ca 0.1–0.5 Mg 0.9–0.5 (CO 3 ) 2 , and K 6 Ca 2 (CO 3 ) 5 . The other minimum, a liquid with the composition of 62 K 2 CO 3 ·38Ca 0.72 Mg 0.28 CO 3 is in equilibrium with K 2 CO 3 , K 4 CaMg(CO 3 ) 4 , and K 6 Ca 2 (CO 3 ) 5 . At 900 °C, the ternary diagram contains two- and three-phase regions with Ca-magnesite, aragonite, K 2 Ca 3 (CO 3 ) 4 , K 2 Ca(CO 3 ) 2 , K 6 Ca 2 (CO 3 ) 5 , K 2 CO 3 , K 2 Ca 0.1–0.5 Mg 0.9–0.5 (CO 3 ) 2 solid solution, K 2 Mg 0.9 Ca 0.1 (CO 3 ) 2 , and K 4 CaMg(CO 3 ) 4 . We also expect an existence of primary phase fields for K 6 Ca 2 (CO 3 ) 5 , K 2 Ca 3 (CO 3 ) 4 and aragonite. We suggest that extraction of K from silicate to carbonate components should decrease the minimum melting temperature of dry carbonated mantle rocks up to 1000 °C at 6 GPa and yield ultrapotassic Ca-rich dolomite melt containing more than 10 mol% K 2 CO 3 . As temperature increases above 1200 °C the melt evolves toward an alkali-poor, dolomitic liquid if the bulk molar CaO/MgO ratio 〉1, or toward K-Mg-rich carbonatite if bulk CaO/MgO 〈 1. The majority of compositions of carbonatite inclusions in diamonds from around the world fall within the magnesite primary field between the 1300 and 1400 °C isotherms. These melts could be formed by partial melting of magnesite-bearing peridotite or eclogite with bulk Ca/Mg 〈1 at temperatures ≤1400 °C. A few compositions revealed in the Ebelyakh and Udachnaya diamonds (Yakutia) fall within the dolomite primary field close to the 1200 °C isotherm. These melts could be formed by partial melting of dolomite-bearing rocks, such as carbonated pelite or eclogite with bulk Ca/Mg 〉1 at temperatures ≤1200 °C.
    Print ISSN: 0003-004X
    Electronic ISSN: 1945-3027
    Topics: Geosciences
    Published by Mineralogical Society of America
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 3
    facet.materialart.
    Unknown
    Relaxation Dynamics of Photoexcited Excitons in Rubrene Single Crystals Using Femtosecond Absorption Spectroscopy (2012)
    American Physical Society (APS)
    Details
    Publication Date: 2012-08-31
    Description: Author(s): S. Tao, N. Ohtani, R. Uchida, T. Miyamoto, Y. Matsui, H. Yada, H. Uemura, H. Matsuzaki, T. Uemura, J. Takeya, and H. Okamoto The relaxation dynamics of an exciton in rubrene was investigated by femtosecond absorption spectroscopy. Exciton relaxation to a self-trapped state occurs via the coherent oscillation with 78  cm -1 due to a coupled mode of molecular deformations with phenyl-side-group motions and molecular displace... [Phys. Rev. Lett. 109, 097403] Published Thu Aug 30, 2012
    Keywords: Condensed Matter: Electronic Properties, etc.
    Print ISSN: 0031-9007
    Electronic ISSN: 1079-7114
    Topics: Physics
    Published by American Physical Society (APS)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 4
    facet.materialart.
    Unknown
    Phase relations in the system FeCO3-CaCO3 at 6 GPa and 900-1700 {degrees}C and its relation to the system CaCO3-FeCO3-MgCO3 (2014)
    Mineralogical Society of America
    Details
    Publication Date: 2014-04-02
    Description: The subsolidus and melting phase relations in the CaCO 3 -siderite system have been studied in multi-anvil experiments using graphite capsules at pressure of 6 GPa and temperatures of 900–1700 °C. At low temperatures, the presence of ankerite splits the system into two partial binaries: siderite + ankerite at 900 °C and ankerite + aragonite up to 1000 °C. Extrapolated solvus curves intersect near 50 mol% just below 900 °C. At 1100 and 1200 °C, the components appear to form single-phase solid solutions with space group symmetry R c , while CaCO 3 maintains aragonite structure up to 1600 °C and 6 GPa. The FeCO 3 solubility in aragonite does not exceed 1.0 and 3.5 mol% at 900–1000 and 1600 °C, respectively. An increase of FeCO 3 content above the solubility limit at T 〉 1000 °C, leads to composition-induced phase transition in CaCO 3 from aragonite, Pmcn , to calcite, R c , structure, i.e., the presence of FeCO 3 widens the calcite stability field down to the P-T conditions of sub-cratonic mantle. The siderite-CaCO 3 diagram resembles a minimum type of solid solutions. The melting loop for the FeCO 3 -CaCO 3 join extends from 1580 °C (FeCO 3 ) to 1670 °C (CaCO 3 ) through a liquidus minimum near 1280 ± 20 °C and 56 ± 3 mol% CaCO 3 . At X (Ca) = 0–30 mol%, 6 GPa and 1500–1700 °C, siderite melts and dissolves incongruently according to the reaction: siderite = liquid + fluid. The apparent temperature and X (Ca) range of siderite incongruent dissolution would be determined by the solubility of molecular CO 2 in (Fe,Ca)CO 3 melt. The compositions of carbonate crystals and melts from the experiments in the low-alkali carbonated eclogite ( Hammouda 2003 ; Yaxley and Brey 2004 ) and peridotite ( Dasgupta and Hirschmann 2007 ; Brey et al. 2008 ) systems are broadly consistent with the topology of the melting loop in the CaCO 3 -MgCO 3 -FeCO 3 system at 6 GPa pressure: a Ca-rich dolomite-ankerite melt coexists with Mg-Fe-calcite in eclogites at CaO/MgO 〉 1 and Mg-dolomite melt coexists with magnesite in peridotites at CaO/MgO 〈 1. However, in fact, the compositions of near solidus peridotite-derived melts and carbonates are more magnesian than predicted from the (Ca,Mg,Fe)CO 3 phase relations.
    Print ISSN: 0003-004X
    Electronic ISSN: 1945-3027
    Topics: Geosciences
    Published by Mineralogical Society of America
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 5
    facet.materialart.
    Unknown
    Phase relationships in the system K2CO3-CaCO3 at 6 GPa and 900-1450 {degrees}C (2014)
    Mineralogical Society of America
    Details
    Publication Date: 2014-12-24
    Description: Phase relations in the system K 2 CO 3 -CaCO 3 have been studied in the compositional range, X (K 2 CO 3 ), from 100 to 10 mol%, at 6.0 GPa and 900–1450 °C. At 900–950 °C, the system has three intermediate compounds: K 6 Ca 2 (CO 3 ) 5 , K 2 Ca(CO 3 ) 2 , and K 2 Ca 3 (CO 3 ) 4 . The K 2 Ca(CO 3 ) 2 compound decomposes to the K 6 Ca 2 (CO 3 ) 5 + K 2 Ca 3 (CO 3 ) 4 assembly above 950 °C. The K 6 Ca 2 (CO 3 ) 5 and K 2 Ca 3 (CO 3 ) 4 compounds melt congruently slightly above 1200 and 1300 °C, respectively. The eutectics were established at 64 and 44 mol% near 1200 °C and at 23 mol% near 1300 °C. K 2 CO 3 remains as a liquidus phase at 1300 °C and 75 mol% and melts at 1425 ± 20 °C. Aragonite remains as a liquidus phase at 1300 °C and 20 mol% and at 1400 °C and 10 mol%. CaCO 3 solubility in K 2 CO 3 and K 2 CO 3 solubility in aragonite are below the detection limit (〈0.5 mol%). Infiltration of subduction-derived K-rich Ca-Mg-Fe-carbonatite into the Fe 0 -saturated mantle causes the extraction of (Mg,Fe)CO 3 components from the melt, which shifts its composition toward K-Ca-carbonatite. According to our data this melt can be stable at the P-T conditions of subcratonic lithosphere with geothermal gradient of 40 mW/m 2 corresponding to temperature of 1200 °C at 6 GPa.
    Print ISSN: 0003-004X
    Electronic ISSN: 1945-3027
    Topics: Geosciences
    Published by Mineralogical Society of America
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 6
    facet.materialart.
    Unknown
    Obesity-induced gut microbial metabolite promotes liver cancer through senescence secretome (2013)
    Nature Publishing Group (NPG)
    Details
    Publication Date: 2013-06-28
    Description: Obesity has become more prevalent in most developed countries over the past few decades, and is increasingly recognized as a major risk factor for several common types of cancer. As the worldwide obesity epidemic has shown no signs of abating, better understanding of the mechanisms underlying obesity-associated cancer is urgently needed. Although several events were proposed to be involved in obesity-associated cancer, the exact molecular mechanisms that integrate these events have remained largely unclear. Here we show that senescence-associated secretory phenotype (SASP) has crucial roles in promoting obesity-associated hepatocellular carcinoma (HCC) development in mice. Dietary or genetic obesity induces alterations of gut microbiota, thereby increasing the levels of deoxycholic acid (DCA), a gut bacterial metabolite known to cause DNA damage. The enterohepatic circulation of DCA provokes SASP phenotype in hepatic stellate cells (HSCs), which in turn secretes various inflammatory and tumour-promoting factors in the liver, thus facilitating HCC development in mice after exposure to chemical carcinogen. Notably, blocking DCA production or reducing gut bacteria efficiently prevents HCC development in obese mice. Similar results were also observed in mice lacking an SASP inducer or depleted of senescent HSCs, indicating that the DCA-SASP axis in HSCs has key roles in obesity-associated HCC development. Moreover, signs of SASP were also observed in the HSCs in the area of HCC arising in patients with non-alcoholic steatohepatitis, indicating that a similar pathway may contribute to at least certain aspects of obesity-associated HCC development in humans as well. These findings provide valuable new insights into the development of obesity-associated cancer and open up new possibilities for its control.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Yoshimoto, Shin -- Loo, Tze Mun -- Atarashi, Koji -- Kanda, Hiroaki -- Sato, Seidai -- Oyadomari, Seiichi -- Iwakura, Yoichiro -- Oshima, Kenshiro -- Morita, Hidetoshi -- Hattori, Masahira -- Honda, Kenya -- Ishikawa, Yuichi -- Hara, Eiji -- Ohtani, Naoko -- England -- Nature. 2013 Jul 4;499(7456):97-101. doi: 10.1038/nature12347. Epub 2013 Jun 26.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Division of Cancer Biology, Cancer Institute, Japanese Foundation for Cancer Research, Koto-ku, Tokyo 135-8550, Japan.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/23803760" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Anti-Bacterial Agents/pharmacology ; Bacteria/metabolism ; Bile Acids and Salts/metabolism ; Carcinoma, Hepatocellular/complications/etiology/metabolism/prevention & control ; *Cell Aging/drug effects ; Cells, Cultured ; Cytokines/metabolism/secretion ; DNA Damage/drug effects ; Deoxycholic Acid/blood/*metabolism ; Dietary Fats/adverse effects/pharmacology ; Disease Models, Animal ; Fatty Liver/complications/pathology ; Gastrointestinal Tract/drug effects/*metabolism/*microbiology ; Hepatic Stellate Cells/cytology/drug effects/metabolism/*secretion ; Humans ; Interleukin-1beta/deficiency ; Liver Neoplasms/complications/etiology/*metabolism/prevention & control ; Male ; Mice ; Mice, Inbred C57BL ; Non-alcoholic Fatty Liver Disease ; Obesity/chemically induced/*metabolism ; Phenotype ; Risk Factors
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Published by Nature Publishing Group (NPG)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 7
    facet.materialart.
    Unknown
    Discovery of moganite in a lunar meteorite as a trace of H2O ice in the Moons regolith (2018)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2018-05-03
    Description: Moganite, a monoclinic SiO 2 phase, has been discovered in a lunar meteorite. Silica micrograins occur as nanocrystalline aggregates of mostly moganite and occasionally coesite and stishovite in the KREEP (high potassium, rare-earth element, and phosphorus)–like gabbroic-basaltic breccia NWA 2727, although these grains are seemingly absent in other lunar meteorites. We interpret the origin of these grains as follows: alkaline water delivery to the Moon via carbonaceous chondrite collisions, fluid capture during impact-induced brecciation, moganite precipitation from the captured H 2 O at pH 9.5 to 10.5 and 363 to 399 K on the sunlit surface, and meteorite launch from the Moon caused by an impact at 8 to 22 GPa and 〉673 K. On the subsurface, this captured H 2 O may still remain as ice at estimated bulk content of 〉0.6 weight %. This indicates the possibility of the presence of abundant available water resources underneath local sites of the host bodies within the Procellarum KREEP and South Pole Aitken terranes.
    Electronic ISSN: 2375-2548
    Topics: Natural Sciences in General
    Published by American Association for the Advancement of Science (AAAS)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 8
    facet.materialart.
    Unknown
    Social evolution. Oxytocin-gaze positive loop and the coevolution of human-dog bonds (2015)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2015-04-18
    Description: Human-like modes of communication, including mutual gaze, in dogs may have been acquired during domestication with humans. We show that gazing behavior from dogs, but not wolves, increased urinary oxytocin concentrations in owners, which consequently facilitated owners' affiliation and increased oxytocin concentration in dogs. Further, nasally administered oxytocin increased gazing behavior in dogs, which in turn increased urinary oxytocin concentrations in owners. These findings support the existence of an interspecies oxytocin-mediated positive loop facilitated and modulated by gazing, which may have supported the coevolution of human-dog bonding by engaging common modes of communicating social attachment.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Nagasawa, Miho -- Mitsui, Shouhei -- En, Shiori -- Ohtani, Nobuyo -- Ohta, Mitsuaki -- Sakuma, Yasuo -- Onaka, Tatsushi -- Mogi, Kazutaka -- Kikusui, Takefumi -- New York, N.Y. -- Science. 2015 Apr 17;348(6232):333-6. doi: 10.1126/science.1261022. Epub 2015 Apr 16.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Animal Science and Biotechnology, Azabu University, Sagamihara, Kanagawa, Japan. Department of Physiology, Jichi Medical University, Shimotsuke, Tochigi, Japan. ; Department of Animal Science and Biotechnology, Azabu University, Sagamihara, Kanagawa, Japan. ; University of Tokyo Health Sciences, Tama, Tokyo, Japan. ; Department of Physiology, Jichi Medical University, Shimotsuke, Tochigi, Japan. ; Department of Animal Science and Biotechnology, Azabu University, Sagamihara, Kanagawa, Japan. kikusui@azabu-u.ac.jp.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25883356" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Animals, Domestic/*psychology ; *Biological Evolution ; *Bonding, Human-Pet ; *Communication ; Dogs/*psychology ; Female ; *Fixation, Ocular ; Humans ; Oxytocin/*physiology ; Wolves/*psychology
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Published by American Association for the Advancement of Science (AAAS)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 9
    facet.materialart.
    Unknown
    New experimental data on phase relations for the system Na2CO3-CaCO3 at 6 GPa and 900-1400 {o}C (2013)
    Mineralogical Society of America
    Details
    Publication Date: 2013-11-19
    Description: Phase relations in the system Na 2 CO 3 -CaCO 3 have been studied in the compositional range, X (Na 2 CO 3 ), from 100 to 10 mol%, at 6.0 GPa and 900–1400 °C. Below 1100 °C, the system has three intermediate compounds: Na 4 Ca(CO 3 ) 3 , Na 2 Ca 3 (CO 3 ) 4 , and Na 2 Ca 4 (CO 3 ) 5 . The Na 4 Ca(CO 3 ) 3 and Na 2 Ca 3 (CO 3 ) 4 compounds melt congruently slightly above 1200 and 1300 °C, respectively. The eutectics were established at 70 and 52 mol% near 1200 °C and at 21 mol% near 1300 °C. The Na 2 Ca 4 (CO 3 ) 5 compound decomposes to the Na 2 Ca 3 (CO 3 ) 4 + aragonite assembly at 1100 °C. Maximum solid solution of CaCO 3 in Na 2 CO 3 is 6–8 mol% at 1100–1300 °C. Melting of Na 2 CO 3 occurs between 1350 and 1400 °C. Na solubility in aragonite does not exceed the detection limit (〈0.5 mol%). Aragonite remains a liquidus phase at 1300 and 1400 °C.
    Print ISSN: 0003-004X
    Electronic ISSN: 1945-3027
    Topics: Geosciences
    Published by Mineralogical Society of America
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 10
    facet.materialart.
    Unknown
    Melting and subsolidus phase relations in the system Na2CO3-MgCO3{+/-}H2O at 6 GPa and the stability of Na2Mg(CO3)2 in the upper mantle (2013)
    Mineralogical Society of America
    Details
    Publication Date: 2013-11-19
    Description: Phase relations in the Na 2 CO 3 -MgCO 3 system have been studied in high-pressure high-temperature (HPHT) multi-anvil experiments using graphite capsules at 6.0 ± 0.5 GPa pressures and 900–1400 °C temperatures. Sub-solidus assemblages are represented by Na 2 CO 3 +Na 2 Mg(CO 3 ) 2 and Na 2 Mg(CO 3 ) 2 +MgCO 3 , with the transition boundary near 50 mol% MgCO 3 in the system. The Na 2 CO 3 -Na 2 Mg(CO 3 ) 2 eutectic is established at 1200 °C and 29 mol% MgCO 3 . Melting of Na 2 CO 3 occurs between 1350 and 1400 °C. We propose that Na 2 Mg(CO 3 ) 2 disappears between 1200 and 1250 °C via congruent melting. Magnesite remains as a liquidus phase above 1300 °C. Measurable amounts of Mg in Na 2 CO 3 suggest an existence of MgCO 3 solid-solutions in Na 2 CO 3 at given experimental conditions. The maximum MgCO 3 solubility in Na-carbonate of about 9 mol% was established at 1100 and 1200 °C. The Na 2 CO 3 and Na 2 Mg(CO 3 ) 2 compounds have been studied using in situ X-ray coupled with a DIA-type multi-anvil apparatus. The studies showed that eitelite is a stable polymorph of Na 2 Mg(CO 3 ) 2 at least up to 6.6 GPa and 1000 °C. In contrast, natrite, -Na 2 CO 3 , is not stable at high pressure and is replaced by β-Na 2 CO 3 . The latter was found to be stable at pressures up to 11.7 GPa at 27 °C and up to 15.2 GPa at 1200 °C and temperatures at least up to 800 °C at 2.5 GPa and up to 1000 °C at 6.4 GPa. The X-ray and Raman study of recovered samples showed that, under ambient conditions, β-Na 2 CO 3 transforms back to -Na 2 CO 3 . Eitelite [Na 2 Mg(CO 3 ) 2 ] would be an important mineral controlling insipient melting in subducting slab and upwelling mantle. At 6 GPa, melting of the Na 2 Mg(CO 3 ) 2 +MgCO 3 assemblage can be initiated, either by heating to 1300 °C under "dry" conditions or at 900–1100 °C under hydrous conditions. Thus, the Na 2 Mg(CO 3 ) 2 could control the solidus temperature of the carbonated mantle under "dry" conditions and cause formation of the Na- and Mg-rich carbonatite melts similar to those found as inclusions in olivines from kimberlites and the deepest known mantle rock samples—sheared peridotite xenoliths (190–230 km depth).
    Print ISSN: 0003-004X
    Electronic ISSN: 1945-3027
    Topics: Geosciences
    Published by Mineralogical Society of America
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...