The Carboniferous and Permian Systems in central and south Hebei Pro-vince

remained primarily in some fault-depressed basins and paleosynclines

distri-but within an area of more than 3000km

2

with buried depth of 1500-4600m anda total thickness of more than 1000m

In the Permian System

the Shiqianfeng Formation

the Upper and Lower Shihezi Formations are mainly terrestrial clas-tic sediments formed in oxidizing environment

the Shanxi Formation is coal-bearing strata;the Benxi and Taiyuan Formations of the Middle and Upper carbo-niferous are transitional facies of terrestrial and marine sediments in which theTaiyuan Formation consists of coal measure.The Shanxi Formation contains 4-12 coal beds with a total thickness of 8.5-27m;the Taiyuan Formation contains 2-11 coal beds

with a total thick-ness of 2.5-33.5 m.Much carbonaceous and dark mudstones can be found incoal measures.The content of chloroform bitumen“A”is more than 0.2% inthe coal beds

the content of residual organic carbon is generally 0.5-1.0% andchloroform bitumen“A”is 0.048-0.115% in the dark mudstones.Vitrinite reflec-tance of them is greater than 0.5%.These indices show that they are favour-able source rocks.To analyze the hydrocarbon generation of the basin in accordance with tec-togenesis and the conditions of thermoevolution

the Himalayan phase is consi-dered to be an important period

and then the Yanshan phase.The Carboniterous and Permian Systems here have composed a great source-reservoir-cap rock assemblage

which can receive oil and gas from the overlying Eogene too.Thus the assemblage has double oil sources.The trap type on thewhole is considred to be fault-block type.The authors suggest that Wen'an Slop is the most favourable area in oiland gas prospects

and then Shenxian and Langfang ranges;as for the south ofHebei

it is better to seek coal-formed gas.