淅川凌岗遗址中全新世地层的古气候记录

The Palaeo-climatic Record in Mid-holocene of the Ling-gang Site in Xichuan County

根据淅川凌岗遗址T1717剖面地层常量元素氧化物含量、质量磁化率和烧失量指标,恢复了中全新世时期凌岗地区自然环境特征:①石家河文化地层(约4.5～4.3 kaBP)中的碱金属氧化物含量偏高、磁化率值偏低,同时本层自然沉积物的细粒比重高,且矿物成分粘土矿物比重低,表明当时气候温凉干旱;②龙山文化层(约4.1～3.9 kaBP)中的氧化物含量、粘土矿物特征、Rb/Sr、LOI和环境风化指数显示在本层早期为湿热的环境、后期为干凉环境.自然环境差异影响了直接影响农业生产和人地关系,间接调控着新石器文化的发展方向.

Through the proxies of oxides of macro-element, Rb/Sr ratios, Loss on ignition （LOI） , grain-size of deposits and XRD analysis, the paper discussed the paleo-climatic characteristics of double Cultural layers i. e. the Shijiahe Cultural layer （built in app. 4.5 - 4.3 kaBP） and the Longshan Cultural layer （built in app. 4.1 - 3.9 kaBP）. Multi-proxies showed that it was a comparatively cool and drought environment in the period of the Shijiahe Cultural layer for high content of oxides, low magnetic susceptibilities and LOI. However, the pe-riod of the earlier Longshan Culture, both the oxides and LOI appeared an existing warm and wet period. Moreo- ver, the clay mineral analysis by XRD demonstrated a relatively high concentration of vermiculite and goethite. As a result, different natural environments made different future, and the warm-wet climate may be an important factor for evolution of Chinese Culture from the Neolithic to civilized society.