大牛地气田盒3段致密储层评价与预测

EVALUATION AND PREDICTION FOR COMPACTED RESERVOIRS IN HE-3 MEMBER OF DANIUDI GAS FIELD

大牛地气田上古生界气藏具有低压、低孔、低渗、致密的特点,产能普遍较低,储层主要为河流相沉积,非均质性强,气田开发难度很大。为了寻找气田的高产层位和分布区域,为气田的开发部署提供可靠的依据,针对气田主力气层盒3段进行了储层评价和预测的研究。结合盒3段储层的特点,开展了三维储层预测工作,形成了以振幅为主的属性提取分析、以岩性曲线重构为主的岩性反演、以电阻率反演为主的含气性预测等3项行之有效的方法和技术。研究认为,盒3段为辫状河流相沉积,主要储层微相为心滩沉积和河道充填沉积,其中心滩微相是本区的高产部位,河道充填微相产气部位主要分布在下部。通过储层综合评价,把盒3段储层分为了4类,其中一类储层为高产,二类为中高产,三类为低产,四类为非储层。并根据储层预测结果部署了130口开发井,取得了良好的勘探效果。

The reservoirs in Upper Paleozoic of Daniudi gas field are characterized by low pressure, low porosity, low permeability, and compacted sandstone, so its productive capacity is usually low. The reservoir is mainly fluvial sediment with strong heterogeneity, which brings many difficulties to the exploitation of this gas field. In order to discover the layer with high productive capacity and their distribution extents, and to provide reliable evidence for the exploitation of this gas field, aimed at He-3 member, which is the main productive pay zone in this field, the paper performed the research on the reservoir evaluation and prediction. The paper performed 3D reservoir prediction in combination with the properties of the He-3 reservoir, and developed 3 series of effective methods and techniques, including the attribute extraction and analysis method focusing on amplitude, lithology inversion method focusing on lithology curve reconstruction, and gas-bearing property prediction on resistivity inversion. The research results indicated that He-3 member is braided fluvial facies deposit, the reservoir microfacies mainly are channel bar deposit and fluvial channel fill deposit, moreover, the channel bar deposit microfacies is the productive zone in this area, and the productive area in the channel fill deposit microfacies is mainly distributed in the lower part. Through reservoir integrative evaluation research, the reservoirs in He-3 member can be divided into 4 classes: the first one is the reservoir with high productivity; the second is the reservoir with mid-high productivity, the third is the reservoir with low productivity, and the fourth is non-reservoir. Based on the reservoir prediction results, 130 exploitation wells have been deployed, with good exploration results obtained.