陆相断陷湖盆扇三角洲沉积具有相变快、砂体接触关系复杂的特点.以南堡凹陷高76断块沙三1亚段为例,根据岩心、测井和生产动态等资料,分析断陷小湖盆扇三角洲前缘单砂体构型特征,建立扇三角洲前缘三维构型模式.结果表明:研究区扇三角洲前缘砂体发育水下分流河道、河口坝、溢岸及水下分流间湾4种沉积微相类型.单砂体侧向拼接主要有4种样式,即水下分流河道—水下分流河道拼接型、水下分流河道—河口坝拼接型、河口坝—河口坝拼接型、泥岩分隔型.垂向上,单层单砂体发育水下分流河道—河口坝"上河下坝"叠置、多期河道叠置及多期河口坝叠置3种样式.平面上,研究区扇三角洲前缘砂体呈条带状或交织条带状展布,交织条带状砂体由多个单一条带状的单砂体组成.扇三角洲河口坝较发育,位于河口坝的上部,下切河口坝,发育"河在坝上走"的模式.单一水下分流河道砂体厚度介于2.00～6.30 m,宽度介于57.65～499.20 m,平均宽厚比约为41∶ 1;单一河口坝砂体厚度介于2.26～9.60 m,宽度介于106.26～651.00 m,平均宽厚比约为73∶ 1;单一溢岸砂体厚度介于0.60～3.46 m,宽度介于40.08～136.35 m,平均宽厚比约为25∶1.单砂体接触关系不同是井间连通性差异的重要影响因素.该结果为南堡凹陷剩余油挖潜及优化开发方案提供参考.

The difficulty of exploration and development in complicated fault block area is larger than in other areas,especially in rolling development stage.Effective evaluating the potential of hydrocarbon accumulating and screening next development targets is one of major problems.At present,Area 4-2 in Nanpu Sag is in the initial stage of rolling development,and neither its reserves nor yield are enough.In order to discover new reservoirs and open up a favourable new situation,this paper takes Neogene in Area 4-2 in Nanpu Sag as an example for the study.On the basis of hydrocarbon distribution characteristics,hydrocarbon accumulation rules are summarized,and the favorable accumulation conditions are identified.The study shows the following results.① Reservoirs are distributed scatteredly with irregular shapes,and hydrocarbon zones are tufted,with thin thinckness,small range and weak continuity.② There are three kinds of reservoirs in the area:structural reservoir,lithologic reservoir and structural-lithologic reservoir;the main controlling factors are fault sealing and river edge;hydrocarbon accumulation models in study area include "river dike" accumulation models and "isolated updip sandstone" accumulation models.③ Favorable reservoir forming conditions include:thin sandstones inserting in thick mudstone,favorable faultsealing zones,high positions of river cut off by faults are favorable for hydrocarbon accumulations.These results provide theoretical guidance for next rolling potential evaluating in Area 4-2 and reference in other complicated fault blocks like Area 4-2.

南堡油田深部储层水体较深、湖盆面积广、埋藏深，导致深部储层泥质含量较高、压实作用较强，储层较差，寻找优质储层是勘探开发的重点。运用岩心、薄片、扫描电镜和其他分析化验资料系统分析了P1、P2断块的沉积相、储层物性、储层孔隙喉道特征和成岩作用特征，研究了南堡油田深层优质储层特征及其控制因素。结果表明，P1断块发育三角洲相，储集砂体较薄、连通性差，储集空间以次生溶蚀孔隙为主，胶结物和泥质杂基含量高，储层综合评价为中孔、特低渗、细喉道型储层。P2断块发育砂质碎屑流沉积，储集砂体较厚、连通性好，储集空间以次生溶蚀孔隙为主，胶结物和泥质杂基含量少，储层综合评价为中孔、中低渗、中喉道型储层。沉积相和成岩作用对储层影响显著，三角洲相储层较差，砂质碎屑流储层较为优质，且优质储层均发育在强溶蚀相中。

为了研究砂泥岩互层型地层的厚度效应对裂缝发育的影响,塔里木盆地库车坳陷克深气田辫状河三角洲前缘砂泥岩互层型储集层为例,分析了裂缝发育机制,应用数值模拟方法计算了不同厚度砂泥岩互层型地层裂缝的密度、开度和孔隙度,提出了6种砂泥岩组合的裂缝发育模式.数值模拟结果显示,砂岩、泥岩单层厚度越薄,越容易产生裂缝,砂泥岩互层型地层裂缝发育还受到岩层厚度的影响.在相同应力条件下,中、厚层(1.5～10.0m)砂岩可以产生开度大和延伸长的裂缝,裂缝能够延伸至或刺穿泥岩层;薄层(小于1.5 m)砂岩裂缝规模小,对泥岩影响较弱.泥岩厚度相同时,与其组合的砂岩厚度越大,泥岩越容易产生裂缝.当泥岩厚度小于1.0 m时,泥岩受力后自身就容易破裂而产生裂缝.在构造变形相似的区域,辫状河三角洲前缘水下分流河道裂缝孔隙度高,连通性好,可以形成良好的储集层;其次为河口坝;远砂坝和席状砂以及水下分流河道间砂体裂缝孔隙度较低,且裂缝连通性差,难以成为有利储集层.泥岩厚度大干1.0m且与泥岩组合的砂岩厚度小于5.5m时,可以成为隔夹层,对油气起到封隔作用.

The traditional way of single bore wave testing is to make excitation on the ground and receive the signal in the bore,which causes the limitation of the test depth and reduce the test accuracy.In offshore drilling it can not achieve the recitation at all.Therefore,a new technique is required to obtain the shear wave for wave testing in offshore drilling.The hang wave logging method described in this paper puts both source and detectors into the borehole,thus getting rid of heavy ground source and realizing the convenience of the wave logging equipments.It is a one-double device.In this method,two detectors are used with the interval of 1 m to receive S-wave propagation signal and then determine the formation wave velocity of the borehole through using the S-wave arrival time difference by the sensor.The method played an important role in the platform survey of the Nanpu oilfield.The authors carried out shear wave logging for a borehole 120 m in depth and obtained a good testing result.The results provided accurate shear wave velocity for the project and played an important role in dividing the field soil types.

In this paper,upon the interpretation of shallow seismic profile data Brom Nanpu waters in Jidong acquired in 2007,the authors established the Quaternary stratigraphic seguence in accordance with the lithological changes,sediment density,water resistance,gas content,sediment structure,surface features,continuity and extension of sediments.Interpretation was also made for major geohagard feafures,such as buried river channels,shallow gas,active faults.The problems encountered in shallow seismic interpretation,such as the second wave and so on,are discussed.