CAJ | 학술논문

异重流（hyperpycnal flows）是指在汇水盆地水深足够条件下，由于携带大量沉积物颗粒，导致流体密度大于稳定环境水体的密度，流体受浮力影响小，沿盆地底部流动的高密度流体，在海水环境中形成异重流的临界沉积物密度为36～43 kg／m3（体积浓度1.3％～1.7％）。异重流主要受洪水触发形成；从河口到汇水盆地经过回流区、深度有限流区、潜入区的演化，最终形成异重流；主要经历“早期沉积—侵蚀过路—晚期沉积”的沉降过程，在沉积近端以侵蚀充填沉积为主，远端以持续沉积为主；异重流的形成及其沉积主要受地形、气候、物源的控制，地形高差大、半干旱气候条件、丰富的细粒悬浮沉积物供给有利于异重流形成。异重流沉积特征及沉积序列受“源—汇”系统的控制，以流水成因交错层理、层内突变接触面或侵蚀接触面、碳质碎屑和植物碎片为区别于其他深水重力流沉积的典型沉积构造；沉积序列由沉积近端到沉积远端可能依次发育厚层序列、逆正粒序序列、薄层细粒序列。异重流研究具有十分重要的意义，能够丰富和完善深水重力流理论、探究古气候变化和古洪水作用规律、合理解释深水重力流沉积和砂体分布特征、指导深水常规和非常规油气的勘探。
이중류（hyperpycnal flows）시지재회수분지수심족구조건하，유우휴대대량침적물과립，도치류체밀도대우은정배경수체적밀도，류체수부력영향소，연분지저부류동적고밀도류체，재해수배경중형성이중류적림계침적물밀도위36～43 kg／m3（체적농도1.3％～1.7％）。이중류주요수홍수촉발형성；종하구도회수분지경과회류구、심도유한류구、잠입구적연화，최종형성이중류；주요경력“조기침적—침식과로—만기침적”적침강과정，재침적근단이침식충전침적위주，원단이지속침적위주；이중류적형성급기침적주요수지형、기후、물원적공제，지형고차대、반간한기후조건、봉부적세립현부침적물공급유리우이중류형성。이중류침적특정급침적서렬수“원—회”계통적공제，이류수성인교착층리、층내돌변접촉면혹침식접촉면、탄질쇄설화식물쇄편위구별우기타심수중력류침적적전형침적구조；침적서렬유침적근단도침적원단가능의차발육후층서렬、역정립서서렬、박층세립서렬。이중류연구구유십분중요적의의，능구봉부화완선심수중력류이론、탐구고기후변화화고홍수작용규률、합리해석심수중력류침적화사체분포특정、지도심수상규화비상규유기적감탐。
In catchment basins whose depth of water is deep enough,hyperpycnal flows develop when the flow carries sediment particles in large quantity,making the fluid density being greater than the water density in stable environment,being a kind of high density fluid flow along the bottom of the basin without much effect from the buoyancy.The threshold density of sediment to develop hyperpycnal flows in marine environment is 36~43 kg/m3 , and 1 .3%~1 .7% of volume concentration.Hyperpycnal flows would mainly be triggered by flood,and formed from the estuary into catchment basins through different regions of backwater zone,depth-limited plume zone and plunging plume zone.Hyperpycnal flows are produced through three major sedimentation stages as early deposition, erosion—bypass and late deposition, making the sedimentation erosion—filling proximal whereas continuous deposition distal.The formation and sedimentation of hyperpycnal flows are controlled by factors of topography, climate and source,and hyperpycnal flows are likely to develop under conditions of obvious terrain elevation difference, semiarid climate conditions and abundant fine suspended sediments supply. The sedimentary characteristics and sedimentary structure are controlled by the “source to sink”system,and are distinct from other deep-water gravity flow deposits because of the typical sedimentary structures such as water causes cross-beddings, the sharp contact surfaces between layers or erosion contact surfaces and coal fragments and leaves.As for sedimentary structure of hyperpycnites,massive sand bed,inversely-to-normally graded bed,thin layer and fine grained bed develop in turn from proximal to distal.The research of hyperpycnal flows is of great significance, which would enrich and perfect the deep-water gravity flow theory,explore the paleoclimate change and paloeflood regularity,explain sedimentary characteristics of the deep-water gravity flow and sand body distribution and direct deep-water conventional and unconventional petroleum exploration as well.