准噶尔盆地春光地区新近系沙湾组辫—曲演化与成藏特点

春光地区为准噶尔盆地西北缘重要的含油气区块之一，新近系沙湾组为主要的产能、探明储量贡献层系。为满足精细勘探的需求，亟需对沙湾组的沉积特征、沉积演化和成藏模式进行深入研究。综合应用岩心、测井和地震资料，通过地层沿层切片分析，认为研究区发育辫状河、曲流河沉积，且同一时期存在“东辫西曲”的沉积特征，明确了不同时期的沉积演化过程；通过构造沉降及地形、基准面旋回变化、物源供给及古气候分析，明确河型转换控制因素；通过对不同河型油气藏成藏特点及识别特征的分析，建立了新的成藏模式，形成立体成藏格局；结合成藏认识，明确了有利勘探方向，有效拓展了勘探领域，取得了较好的勘探效果，为春光地区的增储上产提供了理论支撑。 

Meander-braided transition features and hydrocarbon accumulation characteristics in Neogene Shawan Formation,Chunguang exploration block,Junggar Basin

The Chunguang exploration area is one of the important oil-gas bearing blocks on the northwestern margin of Junggar Basin. Considerable number of high-yield wells have been developed in the Neogene Shawan Formation during the earlier exploration stage, and great exploration and development potential in this area were indicated. In order to meet the needs of delicate exploration, a further study of the sedimentary characteristics, sedimentary evolution and reservoir forming models were promising for the further exploration. With the analysis of cores, loggings and amplitude slices, the typical sedimentary microfacies of diara and point bar deposits were identified in the study area. Then it was considered that braided river and meandering river deposits were developed in the study area with the feature of "braided river deposits in the east part of study area and meandering river deposits in the west part". Moreover, the sedimentary evolution process was determined and a new sedimentary model was established. With the flattening of terrain, the continuous rising of base level, the weakening of provenance supply and the changing of climate from humid to heat, the sedimentary system was gradually transformed from braided river deposits to meandering river deposits. By the study of reservoir accumulation and recognition characteristics of different river-type deposits, a new reservoir forming model was built. Combined with the understanding of reservoir formation, the favorable exploration direction was indicated, the exploration field was effectively expanded, and good exploration results were obtained, which provided theoretical support for the increase of reserves and production in the Chunguang exploration area.