辽河茨榆坨潜山太古界裂缝型储层特征及其控制因素

运用岩心观察、薄片鉴定、物性实测、裂缝统计、包裹体分析、裂缝分形等技术方法，研究了茨榆坨潜山太古界裂缝型储层特征及其控制因素。结果表明:茨榆坨潜山太古界4类变质岩中，黑云母二长片麻岩是最主要的储集岩，裂缝最为发育；黑云母钾长片麻岩次之，裂缝较发育；蚀变煌斑岩、黑云母角闪变粒岩均为非储集岩。茨榆坨潜山储集空间主要是裂缝和微裂隙，太古界储层主要发育北东向和北西向两组裂缝，以高角度张性裂缝为主，形成于中生代中、晚期；部分张剪性裂缝形成时间不晚于古近纪晚期。潜山储层的裂缝以细、微缝最发育，其宽度和面孔率之间存在着正相关性。控制研究区太古界储层裂缝发育的因素有岩性、断层、深度、古风化作用、溶解作用、岩浆侵入、裂缝组合等。

Characters and Controlling Factors on the Archean Fracture-type Reservoirs of the Ciyutuo Buried Hill in the Liaohe Basin

Based on core observation,thin-section analysis,physical property testing,fracture statistics,fluid inclusions analysis and fracture fractal research,it is concluded that there are four types of metamorphic rocks in the Archean Ciyutuo buried hill.Biotite feldspar gneiss is the main type of reservoir rock with mostly-developed fractures;the fractures in biotite potassic feldspar gneiss were less developed while altered lamprophyre and biotie hornblendite granulite could not serve as reservoir rocks.The main reservoir spaces in Archean are mainly tensional,steeply dipped fractures oriented in NE and NW directions and micro-cracks formed in the middle or the Late Mesozoic.Parts of tension-shear fractures were formed in the Late Paleogene Period.Small and micro fractures are the most developed fractures in the buried hill reservoir,whose width and areal porosity are positively related.The main controlling factors on fracture development in the Archeozoic reservoir of Ciyutuo buried hill involve the lithology,fault,depth,weathering,dissolution,magmatic intrusion,fissure assemblages and so on.