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This chapter gives a description of the research history and development of our current understanding of paleoclimate and paleoenvironments in China. It outlines major questions that have arisen after years of study of the Asian monsoon-arid climate system. Modern natural geography is introduced and this sets the stage for detailed reviews in the following chapters. [ABSTRACT FROM AUTHOR]

This chapter offers a comprehensive review of loess studies on the Loess Plateau, and how they provide evidence for past monsoon variability. The chronological framework that has been established for the Loess Plateau with the use of multiple chronometers is explained in detail. Sedimentological, paleomagnetic and geochemical climate proxies are also discussed, and the history,variability and dynamics of the paleomonsoon is described at tectonic, orbital and millennial time scales. [ABSTRACT FROM AUTHOR]

In geotechnical engineering the techniques of site investigation for soils are well established and little is known for the characterisation of municipal solid waste landfills. This paper presents the findings of geotechnical investigations for characterization of landfills situated in vicinity of large cities of seismically active regions of Central Asia. The site investigations using boreholes and geotechnical laboratory tests have been conducted on the landfill site Ahangaranskaya situated at Tashkent Region, Uzbekistan. [ABSTRACT FROM AUTHOR]

Investigation of the outcomes of natural disasters considering the regional situation of paramount importance, because of many of the requirements and necessities will be distinguished in advance and direct the trend of urban development in order to face the least possible risk in cause of critical situations. Gorgan is a ancient city in north east of Iran, although this region is located the distance from coastal ground of Caspian sea, but the many of region for urban development to place on grain size sediments and result geotectonic investigation show the much thickness of soils and sediment of grounds are kinds of SM, ML, CL group. Considering the potentiality to generate earthquake and ground water situation can to result. There are related phenomenon earth movement, landslide and liquefaction. Loess sediments of Gorgan are the mayor deposit that covered in the most of area and geotechnic characteristic of loess caused to become more in fluential and natural disasters. The part events for example flood, slumping on slop are the mayor parts of Gorgan, that to develop city and industrial zone. Therefore recognition of vulnerable zones, are important, and the damages resulting from floods, slides is in a close relation with the population density the amount of investment infra structural affairs and level of city and in dustrial development of loess sediment areas. Consequently preventing from erosion of soil and controlling the deposits using establishment of structures along the foothills can be taken as preventive measures. The results of the studies indicate and rate of erosion has brought about unsuitable conditions in the region. the steep un stable geological layers have accelerated the erosion for estimating earth movement geomorphologic and geotechnic factors have been taken in to account and their relation with tectonic a activities and fault scarps have been recognized and indicate movements.(too long) [ABSTRACT FROM AUTHOR]

Loess is a loose, open-structured metastable soil of aeolian origin, predominantly composed of 20–60 µm quartz particles bonded together by clay particles and, in some cases, carbonate compounds. When dry it can withstand high overburden stresses, whilst upon saturation it collapses creating potentially enormous engineering problems. The mechanisms controlling this metastable behaviour involve the disintegration of inter-particle clay and chemical bonding and variations in the pore water pressures (i.e. suctions) during saturation. The paper describes methods of creation of artificial loess samples using an airfall approach to allow the variation of bonding constituents, arrangements and formation processes. The amount of powdered clay added to primary quartz particles (ground silica) was varied and three methods for activation of clay bonding were employed, i.e. water spray, capillary wetting and steaming. The reproducibility of the synthetic loess created was determined through oedometer testing of the resulting samples, the results of which are reported together with those for undisturbed samples of mid-European loess. Similarities and differences are discussed in the context of the likely bonding mechanisms. It is concluded that creation of reproducible synthetic loess samples, while controlling its constituents, makes possible the individual examination of the different parameters that control bonding in loess. [ABSTRACT FROM AUTHOR]

The article focuses on the engineering properties of loess. Topics discussed include factors that influence the behavioural properties of loess, particle shape, particle size, soil fabric, minerals presents in loess, natural moisture content, Atterberg limits, bulk density, permeability and infiltration, collapsibility, and shear strength.

The article presents information on the loess terrain. Topics discussed include the geomorphology of loess terrain, the regional-scale morphology of loess best illustrated by the thick loess terrains in central and eastern Asia, the dominant slope facet on many stable liang and mao forms in North China and the relationship between formative wind systems and loess landscapes.

The article discusses key engineering geomorphological issues. Topics discussed include loess hydrology and pseudo-karst, mass movements in loess, mass movement types, landslide types based on slide mass composition and location of failure plane and landslide types based on their geometry and movement mechanism.

The article provides an introduction to loess, a clastic sediment formed from wind-lain deposits predominantly of silt-size particles that have subsequently been altered by diagnostic processes, principally weathering and pathogenesis. Topics discussed include quartz as the dominant mineral in most of the world's loess, factors behind surface detachment, entrainment and transport of mineral dust by the wind and the process relationship between wind-blown dust transport and loess deposition.

The article presents information on the last glacial cycle. Topics discussed include major impact of the Last Glacial on ground conditions overextensive areas, important changes in the oceans, the degree of temperature change that occurred in the vicinity of the great ice sheets, impact of periglacial conditions and the deposition of silt-sized aeolian material (loess) derived from deflation of outwash plains and moraines.

The article presents information on loess. Topics discussed include quartz as the dominant mineralogy, characteristics of loess terrain, loess permeability, failure of loess slopes as expressed as several types of landslide and best documented from northern China and loess landscapes as a serious threat to the lives and livelihoods of millions of people.