CAJ | 학술논문

三角洲是一类非常重要的沉积相，是油气聚集的有利场所。准确可靠的三角洲沉积模式，对指导油气的勘探和开发有重要意义。关于教科书中经典的三角洲沉积模式和一些相关概念，很少有人质疑过。但研究发现，该模式及一些相关概念存在许多问题，诸如对于三角洲平原、三角洲前缘和前三角洲等亚相的定义含糊不清，各亚相之间缺乏明确的、具可操作性的界限。由于海（湖）平面是波动的，模式中未明确三角洲平原与三角洲前缘究竟以哪种海（湖）平面为界。三角洲平原与正常河流冲积平原的边界、三角洲前缘与前三角洲的边界、前三角洲与正常海（湖）的边界均未明确，也没有系统总结它们各自的识别、区分标志，致使不同的研究者根据自己的理解对古代同一地层可能得出不同的结论。三角洲有多种类型，且不同类型的三角洲沉积特征不同，应有各自的沉积模式，但许多研究者将曲流河三角洲沉积模式用于所有三角洲亚相、微相划分。经典沉积模式中，三角洲前缘发育水下分支河道和水下天然堤，但笔者等研究表明这2个微相不存在。而三角洲平原上普遍发育的砂体---汊口滩与并口滩，在经典三角洲沉积模式中未提及。作者针对三角洲沉积模式存在的各种问题，进行了深入讨论，并结合现代沉积，系统总结了能用于古代沉积不同亚相和微相的识别、区分标志。
삼각주시일류비상중요적침적상，시유기취집적유리장소。준학가고적삼각주침적모식，대지도유기적감탐화개발유중요의의。관우교과서중경전적삼각주침적모식화일사상관개념，흔소유인질의과。단연구발현，해모식급일사상관개념존재허다문제，제여대우삼각주평원、삼각주전연화전삼각주등아상적정의함호불청，각아상지간결핍명학적、구가조작성적계한。유우해（호）평면시파동적，모식중미명학삼각주평원여삼각주전연구경이나충해（호）평면위계。삼각주평원여정상하류충적평원적변계、삼각주전연여전삼각주적변계、전삼각주여정상해（호）적변계균미명학，야몰유계통총결타문각자적식별、구분표지，치사불동적연구자근거자기적리해대고대동일지층가능득출불동적결론。삼각주유다충류형，차불동류형적삼각주침적특정불동，응유각자적침적모식，단허다연구자장곡류하삼각주침적모식용우소유삼각주아상、미상화분。경전침적모식중，삼각주전연발육수하분지하도화수하천연제，단필자등연구표명저2개미상불존재。이삼각주평원상보편발육적사체---차구탄여병구탄，재경전삼각주침적모식중미제급。작자침대삼각주침적모식존재적각충문제，진행료심입토론，병결합현대침적，계통총결료능용우고대침적불동아상화미상적식별、구분표지。
Deltas are an important type of sedimentary facies,and are also good reservoirs for oil and gas.A reliable depositional model of deltas is an essential guide for oil and gas exploration and develop-ment.However,few people have ever queried the classical delta model and relevant concepts in textbooks. But through our study,it is found that there exist many problems about the depositional model and relevant concepts.For example,definitions of delta plain,delta front and prodelta are vague,while the bounda-ries between them are not well defined and hard to determine.The boundary between delta plain and delta front is sea (or lake) level,but the level fluctuates frequently due to tide (or alternating raining and dr-ying seasons),so which level should be the boundary?Similarly,the boundaries between delta plain and fluvial plain,delta front and prodelta, as well as prodelta and normal sea (lake ) are also inexplicit. Their characteristics and distinctions have not been systematically summarized.Thus different researchers may give different interpretations as to sedimentary environments for the same strata.There are various types of deltas,and each type should have its own depositional model.However,many researchers have tried to apply the meandering delta model to all deltas.In the classical model,delta front develops suba-queous distributary channels and subaqueous levees,but this is proved to be wrong by the authors'work in this paper.On delta plain,some new types of sandbodies,branch-mouth bars and branch-coalesce bars are found,but they are not mentioned in the classical delta model.In this paper,the problems within del-ta models are discussed in depth,and especially the distinction characteristics for subfacies and microfa-cies of deltas are summarized on the basis of modern deltas study.