China can be divided into five major tectonic areas:North(Siberian- Mongolian)continental margin area

North continent and continentalmargin area

South continent and continental margin area

South(Gond-wana)continent and continental margin area

and East(Peri-Pacific)conti-nental margin area(extensional tectonic system was superimposed after late Mesozoic).These sedimentary basins have two different basinal architectures

i.e.single-layered and multi-layered architectures

each of them forms adifferent basin prototype.Double classification nomenclature can be usedfor those superimposed basins that composed of various basin prototypes.Thebasins in China can be classified into 8 different types

they are:intraconti-nental rift/rift valley

continental marginal rift/rift valley

craton-rift

cra-tonic fold-rift

cratonic rise-fold

intra-orogenic depression

foredeep andcraton-foredeep.The Indosinian tectonic cycle

being a turning point

the evolutional andsedimentary histories of the pre- and post-Indosinian are quite different.Thepre-Indosinian is characterized by steable and widespread cratonic cover

mainly composed of marine carbonate platform deposit

and forms the lowergas-bearing series while the post-Indosinian is mainly comprised of conti-nental clastic sediments deposited in isolated

different sized intracontinentalbasins

which constitute the upper oil- and gas-bearing series.The lower gas-bearing series spread in an area of nearly 300?10

4

km

2

in which prolific natural gas has been discovered in Sichuan

Tarim

Ordosand Bohai Gulf basins.The upper oil- and gas-bearing series distribute in anarea of 350?10

4

km

2

More than 200 oil and gas fields has been discoveredin the series

constitute over 90% and 60% of our proved oil and gas reservesre spectively.The total petroleum resource in China is 700-1000?10

8

t

of which theresource in the upper series accounts for 60-70%.However

only 10-13% have been proved.Vast vistas is

therefore

still awaiting to be opened up

or rather the upper series will be taken as the main exploration target in aperiod of considerable length.At the same time

of course

a large effort willbe devoted to the exploration of the lower series.The sedimentary basins in China are rather complex.But based on the tec-tonic settings

their oil- and gas-bearing characteristics can be approached by integrating geological

geophysical and geochemical data

and traps andreservoir properties can also be delineated and defined.Thus

taking the ba-sins as a whole

the relational expression proposed by Professor Zhu Xia(1983)can be used to establish computer quantitative dynamic modellingsystem.A thorough study on the sedimentary basins

their petroleum bear-ing regularities and resource assessment can then be made.The resultswould provide scientific basis for exploration deployment.