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The original idea on the structure of Kimozero as a synclinal fold [1] is currently being reconsidered in favor of its anticlinal form [2]. However, this assump tion has not yet been supported by sufficient data. The problem of the morphology of kimberlite bodies is still debatable: is there one disintegrated pipe with several feeders or are there several small pipes juxtaposed in time and space? The major complexity in the study of Kimozero kimberlite is the intense areal metamorphic alterations under the conditions of the greenschist facies and numerous dislocations, which impedes geochemical typing of rocks by lithofacies types.This study was mainly aimed at specification of the geological and structural setting of Kimozero kimber lite and at determination of its geochemical types by relict lithological-facies peculiarities.Kimozero kimberlite is located within the Archean Karelian Craton in the central part of the Onega syn clinorium, in rocks of the Zaonezhskii Complex, in which two spatial levels were distinguished. The lower level intruded by kimberlite includes dolerite sills and carbonaceous schist. The upper level overlying all kimberlite facies includes a dolerite sill containing lenses of carbonaceous schist. The revealed geological and structural relationship between kimberlite and rocks of the Zaonezhskii Complex provides evidence for the intraformational origin of kimberlite during the crustal thinning upon continuous sedimentation. The age of the formation of sediments and dolerite of the Zaonezhskii Complex is estimated as 2060 -1950; the age of kimberlite is 1.92 Ga [2].The Kimozero structure elongated in the NNW direction is a gentle dipping anticline complicated by axial dislocations of the faulting and shear-faulting kinematics. (Fig. 1).Kimozero kimberlite is represented by two facies: diatreme and crater. A detailed petrographic descrip tion of the lithological facies is given in [4].Kimberlite of the crater facies composes a layered lens like body with a maximal thickness of >50 m being exposed on the anticline wings. Rocks of the crater facies are characterized by complex relation ships. Tuff is composed of disintegrated kimberlite material and fragments of host rocks in the cementing groundmass of serpentine or carbonate composition. The textures of rocks vary from fine to medium grained. Tuffites include varieties enriched in disinte grated olivine material (up to 60-70 vol %) corre sponding to the basal horizons and almost olivine free varieties corresponding to the upper horizons of the crater facies of a classic kimberlite pipe [5].Tuffite is characterized by the features of redeposi tion; it has a layered structure and sometimes grada tional bedding gently dipping to the periphery and conforming to the plain structures in carbonaceous schist. The orientation of the bedding provides unam biguous evidence for the anticline character of the structure, which allows us to reconsider an earlier model [6], according to which kimberlite as the "major layered body" fills the ring mulde narro...

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Based on a detailed petrographic investigation and geological observations of the Paleoproterozoic Kimozero kimberlite (Karelia, Russia), we present a new model of kimberlite pipe with multiphase and mono-crater structure. We recognised volcanoclastic and coherent kimberlite series that filled the inner and outer zones of the kimberlite crater. The multiphase structure, emplacement style, petrography and reconstructed size of the Kimozero kimberlite correspond to Phanerozoic kimberlite pipes.