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古近纪早期,地球上发生了古新世-始新世极热气候(PETM)事件,严重影响全球碳循环过程和海陆生态环境系统.依据普通薄片、元素分析、碳同位素、TOC等实验结果.研究了渤海湾盆地济阳断陷湖盆古新世-始新世时期的湖泊环境时空波动变化及其对PETM事件的响应,发现济阳断陷湖盆早期经历了多旋回的演化过程,湖盆中碎屑物质和化学物质的分异作用同时发生,陆地风化作用和化学沉积物质分异指示了极热气候的变化过程;该时期湖水为逐渐咸化的盐湖环境,具有空间的分带性和时间的阶段演化性,湖水咸化是热气候事件发生的直接响应;湖泊的时空波动演化经历了古新世-始新世时期的极热气候(PETM)事件,该事件早期湖泊尚未完全咸化,浮游生物比较繁盛,早期浮游植物对12 CO2的吸收,会导致短暂的湖泊古生产力较高,但是随着湖盆逐渐咸化,生物的活动存活较难,主要以旱生植物为主,古生产力降到最低.由于过量的12 C吸收沉淀,造成湖泊沉积记录中的δ13 C明显负偏,最大可达5×10-3.由此证实全球PETM事件影响了古新世-始新世之交济阳断陷湖盆的时空演化和物质分异过程.
In the early Paleogene, the Pliocene-Eocene very hot climate (PETM) event occurred on the earth, which seriously affected the global carbon cycle and the terrestrial and marine environment system.According to the experimental results of ordinary flake, elemental analysis, carbon isotope and TOC The temporal and spatial variations of lake environment during the Pliocene - Eocene period and their responses to PETM events in the basin of the Jiyang rift basin in the Bohai Bay Basin were studied. The results show that the lake basin of the Jiyang rift basin experienced multi - cycle evolution in the early stage, The differentiation of clastic matter and chemical substances in the lake basin occurred at the same time. The differentiation of the weathering and the chemical sediment of the lake indicates the process of the extremely hot climate change. During this period, the lake water is gradually salinized salt lake environment with spatial zonation The stage evolution of sex and time, the lake saltwater is the direct response to the occurrence of the hot climate event. The evolution of the spatio-temporal fluctuation of the lake underwent the Paleocene-Eocene extremely hot weather (PETM) event, Salinity, plankton are more prosperous, early absorption of 12 CO2 by phytoplankton, will lead to a relatively high ancient paleocapacity of the lake, but with the gradual salinization of the lake, the activity of living organisms more difficult to And the paleoproductivity was the lowest.The paleoclimate of δ13 C in the lake sedimentary records was obviously negative due to the excessive precipitation of 12 C, up to a maximum of 5 × 10-3, confirming that the global PETM event affected the ancient The Temporal and Spatial Evolution and Material Differentiation Process of Poyang Lake Basin during the Pliocene - Eocene.