GENERAL PATTERNS OF PLUTONIC EVOLUTION OF MORB-TYPE MAGMAS IN THE CENTRAL ATLANTIC: CRYSTAL DIFFERENTIATION, REDOX REACTIONS, AND COMPOSITION OF RESIDUAL GRANITOID MELTS

Cover Page

Cite item

Full Text

Open Access Open Access
Restricted Access Access granted
Restricted Access Subscription Access

Abstract

The problems of evolved gabbroic assemblages and local granitoid magmatism in the ocean spreading ridge system are of key importance for understanding the planetary differentiation during the ocean crust formation. The paper presents new data on plutonic assemblages exposed in two different types of tectonic “windows” of the Mid-Atlantic Ridge: the footwall of a large-offset detachment fault (Ashadze Complex, 13° N) and an uplifted wall of a transform fault (Peyve Seamount, 8° N, Vernadsky Fault). Based on mineral compositional trends and MORB-type melt crystallization modeling by COMAGMAT 3.75 program we show regular features of crystal differentiation with fractionation of significant amount of Fe–Ti oxide minerals up to silicic residual melt composition. The simulated decrease of f(O2) down to QFM level due to the closed-system oxygen consumption by crystallization of a large mass of magnetite is indirectly confirmed by the regular occurrence of reactive fayalite in highly evolved gabbroids, as a result of redox interaction of reduced residual melt with the early magnetite. The earliest zircon crystallized in apatite-bearing oxide microgabbro has a low-Hf composition (HfO2 < 1.3 wt. %). Experimental study of melt inclusions in apatite and zircon yields the real major-element composition of the residual granitoid melts. Further differentiation of silicic residual melts in gabbro-hosted felsic injections occurs as zircon enrichment in HfO2 up to 2.3 wt. % (Ashadze complex) and up to 3.5 wt. % (Peyve Seamount).

About the authors

K. N Sholukhov

Institute of Geology of Ore Deposits, Petrography, Mineralogy and Geochemistry, Russian Academy of Sciences

Email: kote1155708@gmail.com
Moscow, Russia

A. N Pertsev

Institute of Geology of Ore Deposits, Petrography, Mineralogy and Geochemistry, Russian Academy of Sciences

Moscow, Russia

L. Ya Aranovich

Institute of Geology of Ore Deposits, Petrography, Mineralogy and Geochemistry, Russian Academy of Sciences

Academician of the RAS Moscow, Russia

I. P Solovova

Institute of Geology of Ore Deposits, Petrography, Mineralogy and Geochemistry, Russian Academy of Sciences

Moscow, Russia

M. A Golunova

Institute of Experimental Mineralogy, Russian Academy of Sciences

Chernogolovka, Russia

S. E Borisovsky

Institute of Geology of Ore Deposits, Petrography, Mineralogy and Geochemistry, Russian Academy of Sciences

Moscow, Russia

N. S Bortnikov

Institute of Geology of Ore Deposits, Petrography, Mineralogy and Geochemistry, Russian Academy of Sciences

Academician of the RAS Moscow, Russia

References

  1. Силантьев С.А., Краснова Е.А., Каннат М., Бортников Н.С., Кононкова Н.Н., Бельтенев В.Е. Перидотит-габбро-трондьемитовая ассоциация пород Срединно-Атлантического хребта в районе 12°58՛ – 14°45՛ с. ш. гидротермальные поля Ашадзе и Логачев // Геохимия. 2011. № 4. С. 399–372.
  2. Dick H.J.B., MacLeod C.J., Blum P., Abe N., Blackman D.K., Bowles J.A., Cheadle M.J., Cho K., Ciążela J., Deans J.R., Edgcomb V.P., Ferrando C., France L., Ghosh B., Ildefonse B.M., Kendrick M.A., Koepke J.H., Leong J.A.M., Liu C., Ma Q., Morishita T., Morris A., Natland J.H., Nozaka T., Pluemper O., Sanfilippo A., Sylvan J.B., Tivey M.A., Tribuzio R., Viegas L.G.F. Expedition 360 summary / Proceedings of the International Ocean Discovery Program. 2017. Т. 360. https://doi.org/10.14379/iodp.proc.360.101.2017
  3. Dick H.J.B. et al. The Atlantis Bank gabbro massif, southwest Indian ridge // Progress in Earth and Planetary Science. 2019. Т. 6. № 1. С. 1–70.
  4. Бортников Н.С., Силантьев С.А., Беа Ф., Монтеро П., Зингер Т.Ф., Сколотнев С.Г., Шарков Е.В. Разновозрастные цирконы и их изотопный состав (Hf, O) в породах осевой зоны Срединно-Атлантического хребта: Свидетельства неоднократного плавления гетерогенной мантии и эпизодической аккреции океанической коры в зоне спрединга // Петрология. 2022. Т. 30. № 1. С. 3–30.
  5. Skolotnev S.G., Sanfilippo A., Peyve A.A., Muccini F., Sokolov S.Y., Sani C., Dobroliubova K.O., Ferrando C., Chamov N.P., Palmiotto C., Pertsev A.N., Bonatti E., Cuf­faro M., Gryaznova A.C., Sholukhov K.N., Bich A.S., Ligi M. Large-scale structure of the Doldrums multi-fault transform system (7–8° N Equatorial Atlantic): preliminary results from the 45th expedition of the R/V AN Strakhov // Ofioliti. 2020. 45(1). P. 25–41. https://doi.org/10.4454/ofioliti.v45i1.531
  6. Basch V., Sanfilippo A., Skolotnev S.G., Ferrando C., Muccini F., Palmiotto C., Ermolaev B.V., Okina O.I., Ligi M. Genesis of oceanic oxide gabbros and gabbronorites during reactive melt migration at transform walls (Doldrums Megatransform System; 7–8° N Mid-Atlantic Ridge) // Journal of Petrology. 2022. Т. 63. № 9. С. egac086. https://doi.org/10.1093/petrology/egac086
  7. Brunelli D., Sanfilippo A., Bonatti E., Skolotnev S., Escartin J., Ligi M., Ballabio G., Cipriani A. Origin of oceanic ferrodiorites by injection of nelsonitic melts in gabbros at the Vema Lithospheric Section, Mid Atlantic Ridge // Lithos. 2020. С. 368–369.
  8. Chen Y., Niu Y., Wang X. et al. Petrogenesis of ODP Hole 735B (Leg 176) Oceanic Plagiogranite: Partial Melting of Gabbros or Advanced Extent of Fractional Crystallization? // Geochemistry, Geophysics, Geosystems. 2019. V. 20. P. 2717–2732.
  9. Пущаровский Ю.М., Разницин Ю.Н., Мазарович А.О. Строение зоны разлома Долдрамс: Центральная Атлантика. М.: Наука, 1991. 224 с. (Тр. ГИН АН СССР; Вып. 459). ISBN 5-02-002154-7.
  10. Шолухов К.Н., Прокофьев В.Ю., Соловова И.П., Борисовский С.Е., Жиличева О.М., Перцев А.Н. Остаточный расплав после кристаллизации оксид-габбро: пример кислого дифференциата MORB в современной океанической коре (комплекс Ашадзе, Центральная Атлантика) // Петрология. 2022. Т. 30. № 1. С. 1–16. https://doi.org/10.31857/S0869590322010071
  11. Kretz R. Symbols for rock-forming minerals // American mineralogist. 1983. Т. 68. № 1–2. С. 277–279.
  12. Beltenev V., Ivanov V., Shagin A., Segeyev M., Rozhdestvenskaya I., Shilov V., Dobretsova I., Cherkashev G., Samovarov M., Poroshina I. New hydrothermal sites at 13° N, Mid-Atlantic ridge // InterRidge News. 2005. 14. P. 14–16.
  13. Ariskin A.A., Barmina G.S. COMAGMAT: development of a magma crystallization model and its petrological applications // Geochemistry International. 2004. V. 42. Suppl. 1. P. S1–S157.
  14. Aranovich L.Y., Pertsev A.N., Girnis A.V., Bortnikov N.S., Antoshechkina P.M. Basalts from MAR at 13°15՛–13°40՛ N: What mixed? // Lithos. 2023. Т. 462. С. 107424.
  15. Bézos A., Humler E. The Fe3+/ΣFe ratios of MORB glasses and their implications for mantle melting // Geochimica et Cosmochimica Acta. 2005. Т. 69. № 3. С. 711–725.
  16. Tribuzio R., Tiepolo M., Thirlwall M.F. Origin of titanian pargasite in gabbroic rocks from the Northern Apennine ophiolites (Italy): insights into the late-mag­matic evolution of a MOR-type intrusive se­quen­ce // Earth and Planetary Science Letters. 2000. V. 176. P. 281–293.
  17. Аранович Л.Я., Бортников Н.С. Новый Zr–Hf геотермометр для магматических цирконов // Петрология. 2018. Т. 26. № 2. С. 109–115.
  18. Pertsev A.N., Aranovich L.Ya., Prokofiev V.Y., Bortnikov N.S., Cipriani A., Simakin S.S., Borisovskiy S.E. Signatures of residual melts, magmatic and seawater-derived fluids in oceanic lower-crust gabbro from the Vema lithospheric section, Central Atlantic // Journal of Petrology. 2015. V. 56. № 6. P. 1069–1088.
  19. Aranovich L.Ya., Bortnikov N.S., Serebryakov N.S., Sharkov E.V. Conditions of the formation of plagiogranite from the Markov Trough, Mid-Atlantic Ridge, 5°52՛–6°02՛ N // Doklady Earth Sciences. 2010. V. 434. № 1. P. 1257–1262.
  20. Dhar A., Ghosh B., Morishita T., Chattopadhaya S., Bandyopadhyay D., Rao N.C., France L., Nguen D.K., Roy S., Koley M. Development of oxy-symplectites in a slow-spreading lower oceanic crust: Insights from the Atlantis Bank Gabbro Massif, Southwest Indian Ridge // American Mineralogist. 2025. V. 110. № 5. P. 776–790.

Supplementary files

Supplementary Files
Action
1. JATS XML
Download

Copyright (c) 2025 Russian Academy of Sciences

Согласие на обработку персональных данных

 

Используя сайт https://journals.rcsi.science, я (далее – «Пользователь» или «Субъект персональных данных») даю согласие на обработку персональных данных на этом сайте (текст Согласия) и на обработку персональных данных с помощью сервиса «Яндекс.Метрика» (текст Согласия).