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Correlation fractal analysis and R/S analysis of four indexes from Core TS95, Tianshuihai Lake, western Tibetan Plateau, FeO, Fe 2O 3, the ratio of Fe 2O 3/FeO, and organic carbon, are conducted. It is found obviously that the 4 time series are chaotic and have Hurst phenomena. The chaotic or abnormal attractors for FeO, Fe 2O 3, Fe 2O 3/FeO and organic carbon are 2.8, 3.2, 2.9 and 2.5 respectively with saturated embedded dimensions ranging from 5 to 6, suggesting that the dynamic system controlling the local climatic and environmental evolution is chaotic. It has definte variables. To establish the system, at least 3 to 4 variables, at most 5-6 variables, are needed. This generally agrees with deep sea oxygen isotope and differs by large from some climatic indexes of loess profiles. The Hurst indexes of the four proxies are FeO 0.85, Fe 2O 3 0.76, Fe 2O 3/FeO 0.65 and organic carbon 0.74 respectively, indicating that they have obviously long run dependence persistence. This is in accordance with previous studies [13-15] . The persistence results most probably from the uplift of Tibetan Plateau. This suggests that in addition to the global vacillation of climate and environment, some local factors such as the uplift of Tibetan Plateau and the change in Tianshuihai Lake drain age, have probably played a role on the proxies of climate and environment. The differences between the four Hurst indexes result possibly from the relatively easy migration of FeO that is influenced by the hydrological change of the drainage. The organic carbon and Fe 2O 3, the two of the four, are probably more suitable to extract the persistence component of environmental evolution.

The Quaternary sediments of the Chiawobao basin in the Xinjiang Autonomous Region, represented by cores from drill wells, were studied to understand their amino acids, fatty acids, sterols, steranes, terpanes and alkanes. As a result, it has been recognized that the organic matter in sediments were mainly derived from zooplankton and phytoplankton, as well as high plnat debris. During early diagenesis, the amino acid content had dropped sharply, and n-alkane with a low molecular weight had been generated from fatty acids through decarboxylic function, whereas sterols seemed to be more stable as compared with fatty acids, and the odd carbon preference in n-alkanes may have remained until the late diagenesis stage. The results from this study have provided valuable data for understanding the evolution of organic matter at the early diagenesis stage.

In order to understand thermal stabilities of various biomarkers in sedimentary rocks, and to utilize them to subdivide the stage of diagenesis and to define the immature oil-generating threshold in the eastern part of China, serial cores from various depths and core samples from well WHI-I, heated in a simulation experiment at various temperatures, have been analysed. As a result, the relative thermal stabilities for alkybenzenes, alkylithophenes, benzohopanes, hopenes, diasterenes, ββ-hopanes, steranes and terpanes have been recognized and it has been suggested that the immature oil-generating threshold could be defined at the depth at which there are no hopenes in sedimentary rocks.