Structural heterogeneities of lithium-bearing layered silicates of paleocarst kimberlites and their prospecting value (Middle-Markhinsky diamond-bearing region, Western Yakutia)

Clay minerals formed as a result of hydrothermal activity within kimberlite pipes were redeposited into the horizons of the Lower Jurassic diamondiferous deposits of the near-facies facies. The mineral composition of the Lower Jurassic Dyakhtar sequence, composed of paleodeluvium and paleokarst deposits, has been studied in the immediate vicinity and at a distance from kimberlite pipes. Mixed-layer minerals with structural heterogeneities, in which an increased concentration (up to 0.1 wt %) of lithium is noted, were found in sections of erosion plumes of weathered varieties of kimberlite rocks. The thickness of sediments with such minerals decreases sharply at distances of more than 2 km from the desired kimberlite body. The identified features in the mineral composition of the deposits overlying kimberlite pipes can be used as new prospecting signs of diamond potential during geological exploration of primary sources of diamonds.