This paper has discussed the Carboniferous lithological and palaeogeograpgical characteristics inthenorthwest ofChina, by the analysis of outcrop sedimentary facies , clastic composition , trace element andREE ,particlesize ,claymineral ,paleocurrent,etal.,inthecombinationwithregionalstratigraphic,palaeotologicandlithologicdata.IntheEarly Carboniferous , there were 5 oldlands,i.e. Aletai oldland, South Junggar oldland,DunhuangZoulangoldland, Alxaoldland,Longxioldland,and10facies,i.e.Kumasulittoralneriticfacies,BuerjinFuyunlittoralneriticfacies ,Bogedalittoral-neritic facies ,North Junggar bathyal-abyssal facies, NorthTianshanbathyalabyssalfacies ,Kelameilialluvial fan–lacustrinefacies,Kelamayialluvialfanlacutrinefacies,SouthTianshanNorthQilianlittoralneriticfacies,Qaidam carbonateplatformfaciesandmiddleQilianlittoralneriticfacies.ThecharacteristicsoflithofaciespalaeogeographyoftheLateCarboniferousaredifferentfromthoseoftheEarlyCarboniferous,andtheareaoftheoldlanddecreases.IntheLateCarboniferous ,therewere5oldlands,i.e.Aletaioldland,NorthJunggaroldland,Mazongshanoldland,DunhuangAlaxaoldland,middleTianshanoldland,and9facies,i.e.Kumasufluvialandlacutrinefacies,BuerjinFuyunfluvialandlacustrinefacies, Kelameili-Balikun littoral-neriticfacies ,BuleKuerleHongliuyuanlittoralneriticfacies,KelamayiHamibathyal–abyssal facies, Wulumuqi organic moundshoalfacies,Qaidam carbonateplatformfacies ,Zongwulongshanneritic-abyssalfaciesand Qilianlittoralneriticfacies.The bathyalabyssalfacies,littoralfacies,neriticfaciesanddeltafaciesarebeneficial to the exploration of oil and gas.
