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Fine-grained disseminated carbonate was found in Holocene sediments in a core taken from the northern basin of Lake Baikal. The core had two distinct facies. a terrigenous blue-clay overlain by a diatomaceous silt. Oxygen and carbon stable isotope analyses, combined with SEM , X-ray diffraction and .palynology, show that the carbonate in the blue-clay layer is pedogenic in origin, rather than biogenic or authigenic . The S C values in the blue clay suggest that the carbonate is derived from a single source , while the carbonate in the diatom-rich layer might be transported by winds from different sources. On the assumption that the carbonate was formed during the post-glacial age and was transported primarily by river runoff, the 18O isotopic values suggest that the annual temperature in the northern Baikal drainage area was about 3℃ warmer during the middle Holocene (8500-7000 a, B. P.) than during the early Holocene (11 000-8 500a, B.P.) when the blue clay was being deposited . This interpretation is
Fine-grained disseminated carbonate was found in Holocene sediments in a core. From the northern basin of Lake Baikal. The core had two distinct facies. A terrigenous blue-clay overlain by a diatomaceous silt. Oxygen and carbon stable isotope analyzes, combined with SEM , X-ray diffraction and .alynology, show that the carbonate in the blue-clay layer is pedogenic in origin, rather than biogenic or authigenic. The SC values in the blue clay suggest that the carbonate is derived from a single source, while the On the assumption that the carbonate was formed during the post-glacial age and was locked in by river runoff, the 180 isotopic values suggest that the annual temperature in the northern Baikal drainage area was about 3 ℃ warmer during the middle Holocene (8500-7000 a, BP) than during the early Holocene (11 000-8 500a, BP) when the blue clay was being deposited. Thi s interpretation is