EGU2020-4994
https://doi.org/10.5194/egusphere-egu2020-4994
EGU General Assembly 2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

Bumerang pipe Ary Mastakh field Upper Anabar region Yakutia – relatively fertile mantle in the transitional part between Anabar shield and Magan trerrane

Sergei Kostrovitsky1 and Igor Ashchepkov2
Sergei Kostrovitsky and Igor Ashchepkov
  • 1Viinogradov Institute of geochemistry SB RAS Irkutsk, Russian federation
  • 2Institute of Geology and Mineralogy SB RAS, Geology, Novosibirsk, Russian Federation (igor.ashchepkov@igm.nsc.ru)

The Bumerang kimberlite pipe is unusual for the Anabar shield because it  contain great amount of the pyroxene both of Cr  diopside and  eclogite type and commonly in Anabar region the mantle is ultra-depleted and even garnets occurs rarely in kimbelrites (Ashchepkov et al (2010, 2014; 2015;).  This is because the pipe is close to the Margin of Anabar shield in the transition permeable zones   

The PTX diagram show presence of the rare pyrope garnets to 6 GPa of lherzolitic pipe and grate amount of the eclogitic garnets mainly of Fe of type

Both eclogitic and Cr diopside garnets occurs mainly in the middle part of the SCLM within the in the pyroxenite layer.

The ilmenite give long fractionation trend.  From the LAB to the GPa 2.5  which is typical of the Magan terrane (Mir, Internationalnaya pipes etc.).

The pyroxenes mostly have straight-line REE patterns, which create the fan - as series .They most depleted, have some Ba, U peaks of subduction type but deep Pb minima evidencing about the fractionations.  

The garnets  of subduction type reveals the U peaks and all have EU, Sr, minima and varying Ba  The HFSE minima are common But Ta>>Nb  and Zr>Hf/

All this features evidences about possibility of finding of diamond bearing kimbertites within the suture zone between Magan terrane and Anabar shoed in the west part of Yakutian kimberlite province. Grant RFFI 19-05-00788

How to cite: Kostrovitsky, S. and Ashchepkov, I.: Bumerang pipe Ary Mastakh field Upper Anabar region Yakutia – relatively fertile mantle in the transitional part between Anabar shield and Magan trerrane , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4994, https://doi.org/10.5194/egusphere-egu2020-4994, 2020

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