Grain-size Characteristics Of Quaternary Sediments And Its Sedimentary Environment Implication In Xinxiang City

In this thesis, systematic particle size analysis of the Quaternary sediment fromthe drill have been made.The analysis of sedimentary hydrodynamic conditions ofthese sediment and sedimentary cyclicity analysis has been made as well.Inaddition,analysis of the characteristics of sedimentary facies of the research area alsohas been analyzed considering previous data.According to the lithologiccharacteristics of these sediment,sedimentary cycles,seismic facies analysis andPrevious data，this thesis has set up the rock stratigraphic division and correlationprogramme:Holocene diluvium and alluvial deposition layer(Qh),the upper part ofpleistocene series HuiXing town group(Qp3H),the central part of pleistocene seriesShanXian group(Qp2S) and the lower part of pleistocene series SanMengroup(Qp1S).Besides,the stratum under the quaternary period stratum is plioceneseries the phoenix town group(N2F).In addition, on the basis of previous studies,this thesis expounds grain sizecharacteristics and the significance of sedimentary environment according to theaspects of grain size frequency curves,grain size characteristics of cumulativeprobability curves and grain size parameters.According to grading curve,grain sizeparameters and petrography character of the sediment,this thesis has got the regularchange of the sedimentary hydrodynamic conditions of the research area since thelater period of early pleistocene:Qp1S layer(in moderate-low energy)â†'Qp2S-1layer(in moderate energy)â†'Qp2S-2layer(in high energy)â†'Qp3H-1layer(inmoderate-high energy)â†'Qp3H-2layer(in high energy)â†'Qph layer(in low energy).Meanwhile this thesis has preliminarily analysed sedimentary facies of theresearch area.Holocene diluvium and alluvial deposition layer(Qh)ends at15.3m:proluvial and alluviation are main deposition mode.The upper part of pleistoceneseries HuiXing town group(Qp3H)ends at81.05m which can be divided into twoparts.One part is Qp3H-1,ends at81.05m,which is mainly flood plain deposition.Theother part is Qp3H-2,ends at43.75m,which is mainly within-channel deposition.Thecentral part of pleistocene series ShanXian group(Qp2S),ends at166.55m,also can be divided into two parts.The one is Qp2S-1,ends at166.55m,which is mainly floodplain deposition. The other part is Qp2S-2,ends at121.65m,which is mainlywithin-channel deposition and flood plain deposition alternately.The lower part ofpleistocene series SanMen group(Qp1S) ends at195.65m which is mainly flood plaindeposition.As a whole, the sedimentary facies of this research area is mainly riversedimentary facies.