简介:Theacousticemission(AE)featuresinrockfracturearesimulatednumericallywithdiscreteelementmodel(DEM).Thespecimenisconstructedbyusingsphericalparticlesbondedviatheparallelbondmodel.Asaresultoftheheterogeneityinrockspecimen,thefailurecriterionofbondedparticleiscoupledbytheshearandtensilestrengths,whichfollowanormalprobabilitydistribution.TheKaisereffectissimulatedinthefractureprocess,foracubicrockspecimenunderuniaxialcompressionwithaconstantrate.TheAEnumberisestimatedwithbreakagesofbondedparticlesusingapairofparameters,inthetemporalandspatialscale,respectively.ItisfoundthattheAEnumbersandtheelasticenergyreleasecurvescoincide.TherangefortheKaisereffectfromtheAEnumberandtheelasticenergyreleasearethesame.Furthermore,thefrequency-magnituderelationoftheAEnumbershowsthatthevalueofBdeterminedwithDEMisconsistentwiththeexperimentaldata.
简介:Terrestrialfaultedlacustrinebasinisconsideredasafavorableplaceforthedevelopmentofsourcerocks,especiallythefaultbasinsineasternChina.BasedonmolecularcompositionstudyofsaturatedandaromatichydrocarbonsintheextractsofsourcerocksoftheYingchengandShaheziformationsintheLishuFaultDepression,itisrevealedthattheextractsofsourcerocksareprovidedwithlowratioofPr/Ph,lowcontentofC24tetracyclicterpanes,highcontentoftricyclicterpanesandgammacerane,relativelyhighcontentofC27steranesinthesagbeltanditsperiphery;relativelyhighratioofPr/Ph,relativelyhighcontentoftetracyclicterpanesandgammacerane,lowcontentofC27steranesandobviousadvantagesofC29steranesinitsgentleslopebelt;withhighratioofPr/Ph,highcontentofC19,C20tricyclicandC24tetracyclicterpanes,verylowcontentofgammaceraneandC27steranes,andhighcontentofC29steranesintheedgeoffaultdepression.Accordingtotheorganicmatterinputandsedimentaryenvironment,threetypesofsourcerockshavebeenestablished,which,respectively,arethemodeofmixingorganicmatterinputindeepandsemi-deeplake,theadvantageofterrigenousinputinshallowlakeandterrigenousinputinshore-shallowlacustrine.Thefirstmodeissupposedtogenerateoilandgas,whilethesecondonetendstogenerateoil.ThedistributioncharacteristicsofoilandgasintheLishuFaultDepressionareverylikelytobecontrolledbyhydrocarbongeneratingcharacteristicofdifferentsourcerocktypes.