Results 21 to 30 of about 526 (172)

Komatiites, kimberlites, and boninites [PDF]

Journal of Geophysical Research: Solid Earth, 2003
When the mantle melts, it produces ultramafic magma if the site of melting is unusually deep, the degree of melting is unusually high, or the source is refractory. For such melting to happen, the source must be unusually hot or very rich in volatiles. Differing conditions produce a spectrum of ultramafic magma types.
openaire   +3 more sources

Preliminary investigation of the eruption time of kimberlite in the Late Devonian in Mengyin, Shandong

Frontiers in Earth Science, 2023
Kimberlite in the Mengyin area serves as an excellent medium for studying the characteristics and evolutionary processes of the Paleozoic mantle. In order to determine the age of the primary calcite within the kimberlite, in situ carbonate U–Pb dating ...
Ruicong Tian, Haiqin Wang, Jingxiang Tian, Wei Shan, Xiufeng Wang, Naijie Chi, Xiaodong Ma, Zhiyuan Chu, Shenghu Li, Qing Lv   +9 more
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Syn-eruptive agglutination of kimberlite volcanic ash

Volcanica, 2020
Pyroclastic deposits of the Holocene Igwisi Hills kimberlite volcanoes, Tanzania, preserve unequivocal evidence for rapid, syn-eruptive agglutination.
David Haddock, Shukrani Manya, Richard James Brown, Thomas Jones, Fabian Wadsworth, Kate Dobson, Thomas Gernon   +6 more
doaj   +1 more source

Oxide minerals of Kaavi kimberlites (Finland)

Известия высших учебных заведений: Геология и разведка, 2019
The mineralogical and petrogeochemical features of the Neoproterozoic kimberlite rocks of the Lahtojoki and Niilonsuo pipes of the Kaavi cluster (Kaavi-Kuopio, Finland) have been studied, differences in their petrogeochemical composition, quantitative ...
N. S. Azarova, A. V. Bovkun, V. K. Garanin, D. A. Varlamov, H. L. Hong   +4 more
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XENOLITH GARNETS FROM MIR KIMBERLITE PIPE: CHEMICAL COMPOSITION AND EVIDENCE OF METASOMATIC PROCESSES IN THE LITHOSPHERE MANTLE

Геодинамика и тектонофизика, 2022
This paper reports the results on the composition of lithosphere mantle under the Mirny kimberlite field. The authors investigated 57 samples of the mantle xenoliths collected from the Mir pipe.
T. V. Kalashnikova, S. I. Kostrovitsky, K. A. Sinitsyn, E. E. Yudintseva   +3 more
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XENOLITHS OF POLYMICTIC BRECCIAS FROM KIMBERLITES OF THE YAKUTIAN DIAMONDIFEROUS PROVINCE

Геодинамика и тектонофизика, 2022
The polymictic breccias, extremely rare mantle conglomerates being the fragments of rocks and large mantle minerals cemented with fine-grained mass have been long provoking interest of petrologists worldwide.
L. N. Pokhilenko, N. P. Pokhilenko, V. P. Afanasiev   +2 more
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Comparative characteristics of indicator minerals of kimberlites and new perspectives diamond of the Ygyatta diamondiferous region (Western Yakutia)

Известия высших учебных заведений: Геология и разведка, 2019
The new data on the composition of kimberlite indicator minerals (KIM) — pyropes and picroilmenites — of the first kimberlite body T-54-14, opened in 2015 in the Syuldyukar kimberlite field by the geologists of ALROSA PJSC, during the verification of the
T. S. Starkova, M. V. Maltsev, A. V. Tolstov   +2 more
doaj   +1 more source

Kimberlites Identification by Classification Methods [PDF]

, 2007
Kimberlites identification is a very important task for diamond mining. In traditional way, geologists draw upon past experience to do this work. Whether the bedrock should be drilled depends on their analysis of rock samples. This method has two disadvantages.
Yaohui Chai, Aihua Li, Yong Shi 0001, Jing He 0004, Keliang Zhang   +4 more
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Mathematical methods of search for diamond-bearing areas and kimberlite fields in closed territories

Мінеральні ресурси України, 2018
Based on the analysis of the interrelationships between real kimberlite fields and the location of kimberlite tubes of the world, a structural and mathematical method for the search for diamond-bearing regions and kimberlite fields is proposed.
Sh. K. Magazov
doaj   +1 more source

Incipient stages of transformation of round natural diamonds under dissolution in Fe-S melt at high pressure

Литосфера, 2020
Research subject. The article presents the results of a microscopic and photogoniometric study of natural rounded diamonds of tetraghexahedral habit from the kimberlite pipe “Internationalnaya” (Yakutia). The diamonds was partially dissolved in a sulphur-
V. M. Sonin, E. I. Zhimulev, A. A. Chepurov, B. S. Pomazanskiy, V. P. Afanasiev, A. I. Chepurov   +5 more
doaj   +1 more source