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The slip rate of strike-slip active faults is crucial for fault rupture behavior analysis and seismic hazard assessment. Although many segments of the Yilan-Yitong Fault Zone (YYFZ) in NE China have been strongly deformed since the late Quaternary, little progress has been made on its slip rate. With the help of highresolution satellite images, detailed field investigations, seismic reflections, and Quaternary chronological dating, we mainly studied the late Quaternary rightslip rate of the YYFZ. Field investigations revealed an ~15 km long by ~1-2 m high-surface scarp belt extending along the Tangyuan graben interior, with a series of sag ponds and small parallel bulges. Research has revealed that the most recent paleoearthquake (~M 7.0) occurred between 2,800± 600 a BP and 1,700 ± 200 a BP, with evidence of coseismic surface rupture. The T2 terrace abandonment age of the Heijin River is approximately 55.13 ± 1.78 ka (OSL), and the maximum cumulative right-lateral offset may reach 110 ± 5 m. Thus, the maximum right-slip rate of the Tangyuan segment of the YYFZ since the late Quaternary is constrained to 1-2 mm/a according to the upper terrace model. This study suggests that the presence of a new fault in the basin interior merits more attention when assessing the influential surface range and earthquake potential along the YYFZ, and the features of "low tectonic loading rate, activity migration in space, and clustering in time separated by ten thousand years of seismic quiescence" observed along the YYFZ are highly important for earthquake model construction and tectonic deformation studies in stable continental regions (SCRs). [ABSTRACT FROM AUTHOR]

The Quaternary activity of the faults at the eastern end of the Altyn Tagh fault, including the Dengdengshan-Chijiaciwo, Kuantanshan and Heishan faults, was studied on the basis of interpretation of satellite images, trenching, geomorphologic offset measurements and dating. The Altyn Tagh fault has extended eastwards to Kuantanshan Mountain. The left-slip rates of the Altyn Tagh fault decreased through the Qilianshan fault and were transformed into thrust and folds deformation of many NW- trending faults within the Jiuxi basin. Meanwhile, under NE-directed compression of the Tibetan plateau, thrust dominated the Dengdengshan-Chijiaciwo fault northeast of the Kuantanshan uplift with a rate lower than that of every fault in the Jiuxi basin south of the uplift, implying that tectonic deformation is mainly confined to the plateau interior and the Hexi Corridor area. From continual northeastward enlargement of the Altyn Tagh fault, the Kuantanshan uplift became a triangular wedge intruding to the east, while the Kuantanshan area at the end of this wedge rose up strongly. In future, the Altyn Tagh fault will continue to spread eastward along the Heishan and Jintananshan faults. The results have implications for understanding the propagation of crustal deformation and the mechanism of the India-Eurasian collision. [ABSTRACT FROM AUTHOR]

The Da’an-Dedu Fault Zone is a major tectonic feature cutting through the Songliao Basin from south to north in NE China. Five earthquakes with magnitudes over 5 that occurred during the past 30 years suggest the fault zone is a seismogenic structure with future seismic potential. The structural pattern, tectonic history, Quaternary activity and seismic potential have previously been unknown due to the Quaternary sedimentary coverage and lack of large historic earthquakes ( M > 7). In this paper, we use seismic reflection profiles and drilling from petroleum explorations and shallow-depth seismic reflections to study those problems. The total length of the Da’an-Dedu Fault Zone is more than 400 km; modern seismicity delineates it into 4 segments each with a length of 90–100 km. In cross-section view, the folds and associated faults form a complex structural belt with a width of more than 10 km. Shallow-level seismic reflection across the Da’an-Dedu Fault Zone reveals that the Late Quaternary sediments were folded and faulted, indicating its present tectonic activity. The Da’an-Dedu Fault Zone and Songliao Basin have been subjected to three stages of tectonic evolution: a rifting stage characterized by normal faulting and extension (∼145–112 Ma), a prolonged stage of thermal subsidence (∼112–65 Ma), and a tectonic reversal that has been taking place since ∼65 Ma. Our shallow-level reflection profiles show that the folding and reverse faulting have influenced the Late Quaternary sediments. The seismicity and moderate earthquakes suggest that the tectonic activity persists today. The deformation rate across the Da’an-Dedu Fault Zone, however, is measured to be very slow. In conjunction with the inference that most deformation in NE China may be taken up by the Yilan-Yitong Fault Zone bounding the Songliao Basin to the east, we suggest moderate earthquake potential and thus moderate seismic hazards along the Da’an-Dedu Fault Zone. The geological structures, which include anticlines and reverse faults, imply that the Da’an-Dedu Fault Zone has been a contractive structure since ∼65 Ma, and this type of contraction dominates the tectonic deformation in the Songliao Basin and the entire NE China, although the reasons for these conditions need to be further studied. [ABSTRACT FROM AUTHOR]

Abstract: The article discusses on the key problems and the trends of future direction of ecosystem service research. First it reviews the achievements of ecosystem service research, then summarizes the present situation of research of ecosystem service in China, pointing out the main existing problems in value appraisal of ecology service: Ecology service value is measured by simple quantification and double counted; The same appraisal system are applied to different regions and different scales; static method is used to appraise dynamic ecosystem. It holds that the evaluation model in ecosystem service research is not very reasonable, and the method of substitution somewhat farfetched; that subjective factors influence the measure result s; ecology compensation research lags back;and the research lacks driving factors analysis of ecology service function and study on service function forecast and early warning model; and that the researches do not connect ecology service value appraisal with ecological security research. Finally, the article points out the future direction of research [Copyright &y& Elsevier]

Abstract: Get 1116 pieces of literature on research of ecology service value in the period of 2004-2010 from China National Knowledge Internet (CNKI), systematically study the research contents, the publicat ion year/issue, the literature type, the object and region span of study, the involved ecosystem of the literature and process the data with SPSS13.0. We found that (1) increase of research literatures ecology service value in China presents parabolic growth trend in recent years, gradually assumed the inflection point; (2) the study areas assumes huddled together, the West, Southeast, Northeast are the popular studied areas; (3) more empirical study,relatively few theoretical analysis and research summarizes; (4) more studies on land ecosystem, forest ecosystem, wetland, aquatic, shallow seas and tidelands, territory beach/saline ecosystem are many; (5) nature protection areas, famous rivers, famous big lakes, watershed ecosystem, Northeast plain, the Qinghai-Tibet Plain, the hill gully area of Loess Highlands, the rivers in arid area, source areas of water, interlocked belt of farming and animal husbandry, ecosystem along the route of northward rerouting of southern river are research areas of high frequency. (6) Research technique is unitary, imitation many, innovation few. At last, the article points the future direction of research.. [Copyright &y& Elsevier]