Lower-mantle water reservoir implied by the extreme stability of a hydrous aluminosilicate

2014 ◽  
Vol 8 (1) ◽  
pp. 75-79 ◽  
Author(s):  
Martha G. Pamato ◽  
Robert Myhill ◽  
Tiziana Boffa Ballaran ◽  
Daniel J. Frost ◽  
Florian Heidelbach ◽  
...  
2019 ◽  
Vol 117 (1) ◽  
pp. 184-189 ◽  
Author(s):  
Yanhao Lin ◽  
Qingyang Hu ◽  
Yue Meng ◽  
Michael Walter ◽  
Ho-Kwang Mao

The distribution and transportation of water in Earth’s interior depends on the stability of water-bearing phases. The transition zone in Earth’s mantle is generally accepted as an important potential water reservoir because its main constituents, wadsleyite and ringwoodite, can incorporate weight percent levels of H2O in their structures at mantle temperatures. The extent to which water can be transported beyond the transition zone deeper into the mantle depends on the water carrying capacity of minerals stable in subducted lithosphere. Stishovite is one of the major mineral components in subducting oceanic crust, yet the capacity of stishovite to incorporate water beyond at lower mantle conditions remains speculative. In this study, we combine in situ laser heating with synchrotron X-ray diffraction to show that the unit cell volume of stishovite synthesized under hydrous conditions is ∼2.3 to 5.0% greater than that of anhydrous stishovite at pressures of ∼27 to 58 GPa and temperatures of 1,240 to 1,835 K. Our results indicate that stishovite, even at temperatures along a mantle geotherm, can potentially incorporate weight percent levels of H2O in its crystal structure and has the potential to be a key phase for transporting and storing water in the lower mantle.


1997 ◽  
Vol 24 (9) ◽  
pp. 1047-1050 ◽  
Author(s):  
Eiji Ohtani ◽  
Hiroki Mizobata ◽  
Yasuhiro Kudoh ◽  
Toshiro Nagase ◽  
Haruo Arashi ◽  
...  

2021 ◽  
Author(s):  
Lu Liu ◽  
Ziqiang Yang ◽  
Hongsheng Yuan ◽  
Yue Meng ◽  
Nico Giordano ◽  
...  

Abstract The lower mantle, containing both primordial and recycled water, is the most massive potential water reservoir in the Earth. Geophysical and geochemical evidence combined have suggested that the largest heterogeneities in the deep lower mantle may serve as primitive deep-mantle reservoirs hosting a variety of incompatible species including hydrogen. To understand water storage in the deep lower mantle, we conducted experiments in the Fe-O-H, Fe-Al-O-H and Fe-Al-Mg-Si-O-H systems under high pressure-temperature (P-T) conditions, and discovered a previously unknown hexagonal phase (referred to as “H1-phase”) in all the systems. The single-crystal structure of the H1-phase was determined at 79 GPa with a unit-cell of a=10.022(2 )Å and c=2.6121(9) Å and the space group of P63/m, and its composition was obtained as Fe12.76O18H3.7 combining the structure determination and chemical analysis on the recovered sample. More importantly, about 20 mol% of MgO, Al2O3 and SiO2 can be incorporated into the H1-phase in a realistic mantle system Fe-Al-Mg-Si-O-H and its stability field is extended to at least 2400 km along a normal geotherm, implying that the H1-phase can store primordial water in the deepest lower mantle. Therefore, plume-generation zones originated from the deepest lower mantle provide a potential source for higher water contents in basalts associated with mantle plume components.


2018 ◽  
Vol 115 (12) ◽  
pp. 2908-2911 ◽  
Author(s):  
Li Zhang ◽  
Hongsheng Yuan ◽  
Yue Meng ◽  
Ho-kwang Mao

A deep lower-mantle (DLM) water reservoir depends on availability of hydrous minerals which can store and transport water into the DLM without dehydration. Recent discoveries found hydrous phases AlOOH (Z = 2) with a CaCl2-type structure and FeOOH (Z = 4) with a cubic pyrite-type structure stable under the high-pressure–temperature (P-T) conditions of the DLM. Our experiments at 107–136 GPa and 2,400 K have further demonstrated that (Fe,Al)OOH is stabilized in a hexagonal lattice. By combining powder X-ray-diffraction techniques with multigrain indexation, we are able to determine this hexagonal hydrous phase with a = 10.5803(6) Å and c = 2.5897(3) Å at 110 GPa. Hexagonal (Fe,Al)OOH can transform to the cubic pyrite structure at low T with the same density. The hexagonal phase can be formed when δ-AlOOH incorporates FeOOH produced by reaction between water and Fe, which may store a substantial quantity of water in the DLM.


2020 ◽  
Vol 6 (2) ◽  
pp. 147-153
Author(s):  
Muhamad Yusup ◽  
Po. Abas Sunarya ◽  
Krisandi Aprilyanto

System The process of counting and storing in a manual water reservoir analysis has a high percentage of error rate compared to an automated system. In a company industry, especially in the WWT (Waste Water Treatment) section, it has several reservoir tanks as stock which are still counted manually. The ultrasonic sensor is placed at the top of the WWT tank in a hanging position. Basically, to measure the volume in a tank only variable height is always changing. So by utilizing the function of the ultrasonic sensor and also the tube volume formula, the stored AIR volume can be monitored in real time based on IoT using the Blynk application. From the sensor, height data is obtained which then the formula is processed by Arduino Wemos and then information is sent to the MySQL database server via the WIFI network.


Author(s):  
O. A. Lipatnikova

The study of heavy metal speciation in bottom sediments of the Vyshnevolotsky water reservoir is presented in this paper. Sequential selective procedure was used to determine the heavy metal speciation in bottom sediments and thermodynamic calculation — to determine ones in interstitial water. It has been shown that Mn are mainly presented in exchangeable and carbonate forms; for Fe, Zn, Pb и Co the forms are related to iron and manganese hydroxides is played an important role; and Cu and Ni are mainly associated with organic matter. In interstitial waters the main forms of heavy metal speciation are free ions for Zn, Ni, Co and Cd, carbonate complexes for Pb, fulvate complexes for Cu. Effects of particle size and organic matter content in sediments on distribution of mobile and potentially mobile forms of toxic elements have been revealed.


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