【摘要】 混合沉积是指碳酸盐岩与陆源硅质碎屑在沉积上的混合,它是一种沉积机理特殊而又具有重要意义的沉积现象。混合沉积分为4种沉积模式:间断混合,相混合,原地混合和源地混合。通过对南海北部陆坡的研究,识别了其中中新世碳酸盐岩台地、碳酸盐岩斜坡和混合沉积,并对其平面分布进行了研究。结合前人研究,参考区域构造背景,通过地震资料的解释认为研究区的混合沉积属于源地混合沉积,并建立了适合研究区的混合沉积模式。研究区陆源硅质碎屑分别来自北部华南隆起以及西南部中南半岛,而碳酸盐岩碎屑则来自神狐隆起、西沙隆起以及南部的广乐隆起。研究区对混合沉积的影响因素包括构造作用、物源、再改造和沉积作用、海平面升降变化以及气候,对研究区混合沉积起主要作用的是构造作用及海平面升降变化。更多还原

【Abstract】 Mixed sedimentation,which is mixed by carbonate and terrigenous siliciclastics,is an important phenomenon and has special sedimentation mechanism.It can be classified into four depositional models: 1.interrupted sedimentation;2.phase mixture;3.in-situ mixture;4.source mixture.Based on sequence analysis in the slope area of North South China Sea,we identify the carbonate platform,carbonate slope and mixed sedimentation develop in middle Miocene,and generalize its seismic characteristics and distribution.Combined with the pre-study on mixed sedimentation and the regional tectonic background in the study area,we figure out that the mixed sedimentation in this area belongs to the source mixture.In this stratigraphic model,the terrigenous siliciclistics mainly come from South China massif block and the Central South Peninsula,and the carbonate clastics mainly come form Xisha islands,Guangle uplift and Shenhu uplift.In study area,tectonism,input of material(including carbonate and siliciclastics),reworking and redeposition,eustatic sea level change and climate influence the mixed deposition.更多还原