中文摘要：

松辽盆地从青山口组沉积期到姚家组沉积期有重大的古湖泊环境与古气候变化。根据对松辽盆地中部X-22井青山口组-姚家组界线上下12.20m地层的TOC、δ13^org和HI等参数的分析,将该沉积期古湖泊的演化分为三个阶段。最下部TOC含量相对较高、δ13^org偏负、HI中等,反映了当时气候温暖湿润,湖水较深,有机质来源于高等植物和部分藻类,湖底呈还原环境。向上TOC和HI急剧降低,δ13^org略偏正,反映了气候开始变得干热,湖水变浅,湖底呈弱氧化环境,有机质主要来源于高等植物。到了最上部开始出现红层,TOC含量更低,δ13^org进一步偏正,反映气候更加干热、湖水更浅,湖底呈强氧化环境。δ13^org在界线处出现小幅度的正偏,与G-12井的研究结果一致。

英文摘要：

Major paleoenvironmental and paleoclimatic changes occurred from the sedimentary period of the Qingshankou Formation to the Yaojia Formation in the Songliao Basin. Based on detailed analyses on TOC, δ13^Corg and HI from the lower Qingshankou to the upper Yaojia formations in Well Xu-22 of the central Songliao Basin, we have recognized three stages in the evolution of paleolimnology. In the lowest part, TOC is relative high, δ13^Corg values tend to be negative excursion, and index of HI is moderate, reflecting a warmer and moister paleoclimate, relative deeper and anoxic water, as well as organic origin of plants and a few alga. Upward, the TOC and HI decrease dramatically, δ13^ Corg values tend to be sligntly positive excursion, showing that the climate became dry and heat, the water is slightly shallow and oxic, the organic matter is mainly origined from plant. In the uppermost part, TOC is lower, δ13^Corg values tend to be more positive excursion, along with the appreance of red bed, showing that the climate became drier and heater, the basin tended to be shallower and oxic. Further study reveals that δ13^Corg has a positive excursion at the boundary of the Qingshankou and Yaojia formations, as indicated in Well G-12. The excursion of δ13^Corg may be affected by pCO2.