鄂尔多斯盆地上古生界致密砂岩气田储集层特征与成因<sup>*</sup>

付金华, 魏新善, 南珺祥, 石小虎. (2013)鄂尔多斯盆地上古生界致密砂岩气田储集层特征与成因^* [J]. 古地理学报, 15(4): 529-538
Fu Jinhua, Wei Xinshan, Nan Junxiang, Shi Xiaohu. (2013)Characteristics and origin of reservoirs of gas fields in the Upper Paleozoic tight sandstone, Ordos Basin[J]. Journal Of Palaeogeography, 15(4): 529-538. DOI:10.7605/gdlxb.2013.04.042 复制到剪切板

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鄂尔多斯盆地上古生界致密砂岩气田储集层特征与成因^*

付金华^1,³, 魏新善^2,³, 南珺祥^2,³, 石小虎^2,³

1 中国石油长庆油田分公司,陕西西安 710018

2 中国石油长庆油田分公司勘探开发研究院,陕西西安 710018

3 低渗透油气田勘探开发国家工程实验室,陕西西安 710018

第一作者简介: 付金华,男,1963年生,博士,教授级高级工程师,现任中国石油长庆油田公司副总地质师,主要从事油气勘探研究与技术管理工作。E-mail:fjh_cq@PetroChina.com.cn。

收稿日期:2011-04-06

基金:*国家示范工程项目“鄂尔多斯盆地大型低渗透岩性地层油气藏开发示范工程”(编号:2011ZX05044)和中国石油股份公司重大科技专项“长庆油田油气当量上产5000万吨关键技术研究”(编号:2011E-1301)联合资助

摘要

鄂尔多斯盆地上古生界致密砂岩储集层普遍以低孔低渗为主要特征,但在低孔低渗的背景上发育相对优质储集层。应用偏光显微镜、恒速压汞等技术手段,从碎屑岩的粒度、碎屑组分、孔隙结构等分析入手,对比神木气田、榆林气田和苏里格气田3个大气田的储集层特点,并对致密砂岩中相对优质储集层的成因进行了分析。研究认为:高石英类矿物含量、适量的可溶性组分(包括长石、火山岩岩屑及凝灰质等)及残余少量粒间孔形成的酸性流体的渗流通道是形成相对优质储集层的必要条件;而较高含量的千枚岩屑、泥板岩等软组分,在上覆地层压力作用下被压实变形、充填孔隙,造成残余粒间孔全部丧失和酸性流体渗流通道的缺乏,因而形成低孔低渗的致密砂岩储集层。

关键词: 鄂尔多斯盆地; 气田; 上古生界; 致密储集层; 成岩作用; 储集性能

中图分类号:TE122.2⁺21 文献标志码:A 文章编号:1671-1505(2013)04-0529-10

Characteristics and origin of reservoirs of gas fields in the Upper Paleozoic tight sandstone, Ordos Basin

Fu Jinhua^1,³, Wei Xinshan^2,³, Nan Junxiang^2,³, Shi Xiaohu^2,³

1 PetroChina Changqing Oilfield Company,Xi'an 710018,Shaanxi

2 Research Institute of Exploration and Development,PetroChina Changqing Oilfield Company,Xi'an 710018,Shaanxi

3 National Engineering Laboratory for Exploration and Development of Low-permeability Oil & Gas Field,Xi'an 710018,Shaanxi

About the first author: Fu Jinhua,born in 1963,doctor,senior engineer,is the deputy chief geologist of PetroChina Changqing Oilfield Company,and is mainly engaged in oil and gas exploration and technology management.E-mail:fjh_cq@PetroChina.com.cn.

Abstract

The reservoirs in the Upper Paleozoic of Ordos Basin are generally characterized by low porosity and low permeability,but reservoirs with relatively high quality developed in the background of low porosity and low permeability. By means of the polarizing microscope,rate-controlled mercury penetration and other technical methods,based on the analysis of clastic rock granularity,detrital composition and pore structure,comparison and origin analysis of the tight sandstone reservoirs in gas fields,including Shenmu Gas Field,Yulin Gas Field and Sulige Gas Field,were carried out.We concluded that higher content of quartz kind of minerals and adequate amount of soluble components(including feldspar minerals,volcanic rock debris and tuffaceous materials, etc)and the seepage channels for acidic fluid formed by remnants of intergranular pore-space are requirements for relatively high quality reservoirs;higher content of phyllites rock fragments and argillaceous slates,which were deformed under the overlying strata pressure,led to the intense decrease of intergranular pore-space and the lack of seepage channel for acidic fluid,and thus tight sandstone reservoirs with low porisity and low permeability were developed.

Key words: Ordos Basin; gas field; Upper Paleozoic; tight reservoir; diagenesis; reservoir property

Show Figures

随着常规油气资源的日益枯竭, 非常规油气资源已经在油气勘探中占有非常重要的地位。鄂尔多斯盆地上古生界储集层属于河流— 三角洲沉积体系, 热演化程度高, 碎屑组分复杂, 成岩作用强烈, 岩性致密, 属于典型的低渗特低渗非常规天然气藏, 孔隙度一般在10%以下, 渗透率一般小于3× 10^-3 μ m²(付金华等, 2000; 惠宽洋等, 2002; 沈玉林等, 2006; 席胜利等, 2009; 付锁堂等, 2010)。目前, 鄂尔多斯盆地致密砂岩气藏的勘探已取得了重大的突破, 探明储量数万亿立方米。文中对鄂尔多斯盆地致密砂岩气藏的3个典型气田— — 神木气田、榆林气田和苏里格气田(图1)的储集层孔隙结构特征等方面进行对比, 进而探讨了致密砂岩气藏中相对优质储集层的成因。

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	图1 鄂尔多斯盆地气田位置Fig.1 Location of gas fields in Ordos Basin

1 储集层特征

鄂尔多斯盆地上古生界下二叠统太原组和山西组、中二叠统石盒子组(图 2)是研究区致密砂岩大气田的主力产气层。

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	图2 鄂尔多斯盆地上古生界综合地层图Fig.2 Comprehensive column of the Upper Paleozoic in Ordos Basin

神木气田主力产气层为太原组, 储集层岩性以灰色、灰白色粗粒岩屑砂岩和岩屑石英砂岩为主, 石英以单晶石英为主, 多具波状消光, 其中含有丰富的针状包裹体, 碎屑组分分析表明, 其源区岩性以中低级变质岩为主, 并夹有安山质火山岩。岩屑以千枚岩、泥板岩和片岩等软组分为主, 因压实作用强烈变形或呈假杂基充填孔隙, 可溶性组分如喷发岩岩屑以及长石, 含量一般在5%~10%之间(表 1), 压实作用及较高含量的杂基造成该层段缺少原始残余粒间孔。胶结作用以孔隙式胶结为主, 颗粒之间以线状接触为主, 部分凸凹状或缝合线状接触, 结构成熟度和成分成熟度均较低, 杂基含量一般在7%以上。

表1 鄂尔多斯盆地气田致密砂岩储集层岩石组分特征统计 Table1 Statistics of rock components of tight sandstone reservoirs of gas fields in Ordos Basin

榆林气田主力气层为山西组山2段, 主要为三角洲分流河道砂体, 岩性以石英砂岩为主, 储集层的碎屑成分以石英质为主(包括燧石、石英岩岩屑), 次为岩屑成分, 长石含量很少, 平均不足1%。岩屑组分以火山岩、变质砂岩、粉砂岩及中浅变质的片岩、千枚岩、板岩为主。

苏里格气田主力气层为石盒子组盒8段, 岩性为三角洲平原分流河道沉积的中粗粒石英砂岩。石英碎屑成分以单晶石英为主, 少量硅质石英岩型、燧石岩型、片岩型的多晶石英, 含量1%~4%。少数砂岩中可见到长石碎屑, 含量为2%, 岩屑含量10%~20%, 主要为变质岩和岩浆岩岩屑, 火山岩岩屑少量。砂岩结构类型总体上以粗粒砂岩为主, 见少量含砾巨砂岩、含砾粗砂岩, 其次为中粒砂岩及少量细砂岩和不等粒砂岩。

2 储集层孔隙结构特征

2.1 储集层物性特征

神木气田、榆林气田及苏里格气田的砂体发育, 储集层物性具有低孔低渗的总体特征(图 3, 图4, 图5), 其中苏里格气田盒8段, 孔隙度11.1%, 渗透率16.09× 10^-3 μ m²; 榆林气田山2段, 孔隙度7.3%, 渗透率5.12× 10^-3 μ m²; 神木气田太原组, 孔隙度9.6%, 渗透率0.98× 10^-3 μ m²。总体上呈低孔低渗致密砂岩储集层特征(表 2)。

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	图3 神木气田太原组储集层物性特征分布Fig.3 Physical property distribution of reservoirs of the Taiyuan Formation in Shenmu Gas Field

表2 鄂尔多斯盆地上古生界致密砂岩储集层特征 Table2 Characteristics of the Upper Paleozoic tight sandstone reservoirs in Ordos Basin

2.2 孔隙组合类型

在孔隙类型分布频率图(图 6)上可以看出, 3个气田的孔隙类型都以溶孔为主, 超过50%, 其中太原组的溶孔率占到80%以上, 储集空间以溶蚀孔隙为主。粒间孔的含量差异较大, 榆林气田粒间孔含量最大, 接近20%, 苏里格气田次之, 神木气田最小, 不足2%(表 2)。

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	图4 榆林气田山2段储集层物性特征分布Fig.4 Physical property distribution of reservoirs of the Member 2 of Shanxi Formation in Yulin Gas Field

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	图5 苏里格气田盒8段储集层物性特征分布Fig.5 Physical property distribution of reservoirs of the Member 8 of Shihezi Formation in Sulige Gas Field

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	图6 鄂尔多斯盆地气田致密砂岩储集层孔隙类型频率图Fig.6 Pore type frequency diagram of tight sandstone reservoirs of gas fields in Ordos Basin

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	图7 鄂尔多斯盆地大气田致密砂岩储集层典型恒速压汞曲线图Fig.7 Selected rate-controlled mercury penetration curves of tight sandstone reservoirs of gas fields in Ordos Basin

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	图8 鄂尔多斯盆地上古生界致密砂岩储集层孔渗与试气产能(无阻流量)关系Fig.8 Relationship between porosity, permeability and gas testing capacity of the Upper Paleozoic tight sandstone reservoirs in Ordos Basin

2.3 毛管压力曲线特征

根据23口井106个样品压汞曲线(表3)分析表明, 神木气田太原组储集层最大孔喉半径在0.364~2.707, μ m之间, 平均1.066, μ m; 中值孔喉半径在0.02~0.72, μ m之间, 平均0.26, μ m, 总体上储集层孔喉较细小。储集层孔喉分选系数在0.165~3.144之间, 平均1.979, 分选系数较大, 孔喉分选较差。储集层排驱压力和饱和度中值压力较大, 平均分别为0.703 MPa和5.686 MPa。最大进汞饱和度大, 一般在60%以上, 平均76.28%; 退出效率较低, 一般小于40%, 平均39.28%。

表3 鄂尔多斯盆地上古生界致密砂岩储集层压汞曲线参数 Table3 Parameters of mercury penetration curves of the Upper Paleozoic tight sandstone reservoirs in Ordos Basin

气田名称	样品数 /个	孔隙度 /%	渗透率 /10^-3 μ m²	排驱压力 /MPa	中值压力 /MPa	孔喉分选系数	变异系数	均值系数	最大孔喉半径 /μ m	中值孔喉半径 /μ m	最大进汞饱和度/%	退出效率 /%
神木 (太原组)	31	$\begin{matrix} \frac{5.6 ~ 12 . 0^{*}}{8.2} \end{matrix}$	$\begin{matrix} \frac{0.12 ~ 4.50}{0.58} \end{matrix}$	$\begin{matrix} \frac{0.277 ~ 2.055}{0.703} \end{matrix}$	$\begin{matrix} \frac{0.622 ~ 29.947}{5.686} \end{matrix}$	$\begin{matrix} \frac{0.165 ~ 3.144}{1.979} \end{matrix}$	$\begin{matrix} \frac{0.099 ~ 0.324}{0.196} \end{matrix}$	$\begin{matrix} \frac{0.133 ~ 13.02}{10.279} \end{matrix}$	$\begin{matrix} \frac{0.364 ~ 2.707}{1.066} \end{matrix}$	$\begin{matrix} \frac{0.02 ~ 0.72}{0.26} \end{matrix}$	$\begin{matrix} \frac{51.52 ~ 89.73}{76.28} \end{matrix}$	$\begin{matrix} \frac{27.4 ~ 50.31}{39.28} \end{matrix}$
榆林 (山2段)	40	$\begin{matrix} \frac{5.1 ~ 9.8}{7.2} \end{matrix}$	$\begin{matrix} \frac{0.12 ~ 106}{7.68} \end{matrix}$	$\begin{matrix} \frac{0.029 ~ 1.493}{0.345} \end{matrix}$	$\begin{matrix} \frac{0.109 ~ 9.730}{1.279} \end{matrix}$	$\begin{matrix} \frac{1.295 ~ 3.298}{2.437} \end{matrix}$	$\begin{matrix} \frac{0.042 ~ 2.251}{0.305} \end{matrix}$	$\begin{matrix} \frac{5.49 ~ 13.09}{9.472} \end{matrix}$	$\begin{matrix} \frac{0.502 ~ 25.862}{2.174} \end{matrix}$	$\begin{matrix} \frac{0.03 ~ 6.71}{1.59} \end{matrix}$	$\begin{matrix} \frac{61.59 ~ 94.14}{80.72} \end{matrix}$	$\begin{matrix} \frac{33.16 ~ 71.90}{45.67} \end{matrix}$
苏里格 (盒8段)	35	$\begin{matrix} \frac{6.1 ~ 14.6}{9.2} \end{matrix}$	$\begin{matrix} \frac{0.15 ~ 25.85}{10.42} \end{matrix}$	$\begin{matrix} \frac{0.344 ~ 2.529}{0.553} \end{matrix}$	$\begin{matrix} \frac{0.58 ~ 14.99}{1.268} \end{matrix}$	$\begin{matrix} \frac{1.15 ~ 2.27}{1.501} \end{matrix}$	$\begin{matrix} \frac{0.082 ~ 0.201}{0.274} \end{matrix}$	$\begin{matrix} \frac{7.268 ~ 11.37}{9.132} \end{matrix}$	$\begin{matrix} \frac{0.630 ~ 6.136}{1.737} \end{matrix}$	$\begin{matrix} \frac{0.04 ~ 0.33}{0.18} \end{matrix}$	$\begin{matrix} \frac{71.8 ~ 92.06}{81.21} \end{matrix}$	$\begin{matrix} \frac{10.74 ~ 73.02}{47.77} \end{matrix}$

* 注: $\begin{matrix} \frac{5.6 ~ 12.0}{8.2} \end{matrix}$ 表示: $\begin{matrix} \frac{最小值 ~ 最大值}{平值值} \end{matrix}$ 。

表3 鄂尔多斯盆地上古生界致密砂岩储集层压汞曲线参数 Table3 Parameters of mercury penetration curves of the Upper Paleozoic tight sandstone reservoirs in Ordos Basin

榆林气田山2段储集层最大孔喉半径在0.502~25.862μ m之间, 平均2.174μ m; 中值孔喉半径在0.03~6.71μ m之间, 平均1.59μ m, 总体上储集层孔喉较细小。储集层孔喉分选系数在1.295~3.298之间, 平均2.437, 分选系数较大, 孔喉分选较差。储集层排驱压力和饱和度中值压力较大, 平均分别为0.345 MPa和1.279 MPa, 反映油气难以进入储集层之中。最大进汞饱和度大, 一般在70%以上, 平均80.72%; 退出效率较低, 一般小于50%, 平均45.67%。

苏里格气田盒8段储集层最大孔喉半径在0.630~6.136μ m之间, 平均1.737μ m; 中值孔喉半径在0.04~0.33μ m之间, 平均0.18μ m, 总体上储集层孔喉较细小。储集层孔喉分选系数在1.15~2.27之间, 平均1.501, 分选系数较大, 孔喉分选较差。储集层排驱压力和饱和度中值压力较大, 平均分别为0.553 MPa和1.268 MPa, 反映油气难于进入储集层之中。最大进汞饱和度大, 一般在70%以上, 平均81.21%; 退出效率较低, 一般小于50%, 平均47.77%。

相对而言, 苏里格气田盒8段和榆林气田山2段储集层孔喉结构好于神木气田太原组, 其最大孔喉半径、中值孔喉半径和最大进汞饱和度比神木气田太原组大, 而排驱压力、饱和度中值压力、分选系数、变异系数和均值系数比神木气田太原组小, 退出效率苏里格气田盒8段最好。

恒速压汞是近年来发展起来的测定孔隙结构的一个非常先进的技术手段, 在一定的进汞速度条件下, 对孔隙大小、喉道大小、孔隙-喉道配置情况进行测试, 能够准确地反应孔喉分布情况。

恒速压汞实验研究表明, 榆林气田山2段和苏里格气田盒8段储集层孔径明显较大, 介于100~260, μ m之间, 而神木气田太原组储集层在80~140, μ m之间, 排驱压力也明显高于其他两个气田。从孔隙-喉道组合曲线来看, 榆林气田山2段和苏里格气田盒8段明显好于神木气田太原组(图 7)。

总体上储集层具有孔喉较小、分选较差的特点, 即储集层孔喉结构较差。典型的恒速压汞曲线图同样表明, 榆林气田山2段的孔隙结构最好, 苏里格气田盒8段次之(图 7)。

2.4 储集层孔渗与试气产能关系

图8表明, 储集层物性与试气产量有着正相关关系, 孔渗条件越好, 储集层的渗流能力越强, 试气产量也越高。尤其渗透率对产量的影响更大, 相关性达到了0.87。在物性影响因素中, 渗透率的作用更大。

3 低渗致密储集层及相对优质储集层形成机理

鄂尔多斯盆地上古生界碎屑岩储集层独特的碎屑组合特征(软组分如千枚岩、泥板岩以及云母片岩等含量丰富)、埋藏深度较大、热演化程度高、硅质加大极其发育, 是储集层致密化的主要原因; 而局部发育的粒间孔及适量的可溶性组分如火山岩岩屑、凝灰质以及少量的长石的存在是形成相对优质储集层的主要原因(南珺祥等, 2005; 包洪平等, 2007; 杨华等, 2007)。

3.1 丰富的软组分的存在是形成致密储集层的主要原因

研究区软组分主要以千枚岩和泥板岩岩屑为主, 并见少量的二云母片岩和绢云母片岩岩屑、云母等, 这些组分较软, 容易变形, 含量最高可达50%左右, 一般在3%~15%之间。鄂尔多斯盆地上古生界地质历史时期最大埋深可达到4500~5000 m左右(陈荷立, 1995; 吕强等, 2009), 在如此巨大的上覆地层压力作用下, 软组分强烈变形, 部分呈假杂基充填孔隙, 完全堵塞喉道(图 9-1), 使储集层的孔隙度、渗透率急剧降低(图 10)。因此, 软组分的存在不利于酸性流体渗流通道的形成、残余粒间孔的保存和溶孔的形成。

3.2 丰富的硅质加大是形成致密储集层的重要原因之一

鄂尔多斯盆地上古生界碎屑岩储集层热演化程度高, R_O一般在2.0%以上, 泥岩演化程度高, 火山岩岩屑、凝灰质等蚀变作用强烈, 压溶作用发育, 这些反应形成的硅质基本上以硅质加大边的形式存在, 使部分层段由于硅质含量高(表4), 使得颗粒相互“ 焊接” 在一起, 完全丧失了储集性能(图9-2)。

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图9 鄂尔多斯盆地上古生界致密砂岩储集层微观照片
1— 莲7井, 4012.10 m, 假杂基充填孔隙的千枚岩屑, 正交偏光; 2— 莲7井, 4010.10 m, 硅质加大发育, 单偏光; 3— 陕255井, 盒8下, 3273.96 m, 砾状巨粗粒石英砂岩, 岩屑溶孔及粒间孔, 孔隙度为8.4%, 渗透率为1.8× 10^-3 μ m², 单偏光; 4— 陕291井, 盒8下, 3650.45 m, 中粒岩屑砂岩, 塑性岩屑压嵌, 无显孔, 单偏光; 5— 陕375井, 3392.00 m, 绿泥石膜, 粒间孔可见, 单偏光; 6— 陕333井, 盒8下, 3780.90 m, 火山岩岩屑含量7%, 全部溶蚀, 单偏光Fig.9 Microscopic photos of the Upper Paleozoic tight sandstone reservoirs in Ordos Basin

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	图10 鄂尔多斯盆地上古生界致密砂岩储集层软组分含量与物性关系散点图Fig.10 Scatter diagrams showing relationship between soft component content and physical properties of the Upper Paleozoic tight sandstone reservoirs in Ordos Basin

表4 鄂尔多斯盆地上古生界致密砂岩储集层硅质与物性关系 Table4 Relationship between silica content and physical properties of the Upper Paleozoic tight sand- stone reservoirs in Ordos Basin

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	图11 鄂尔多斯盆地上古生界致密砂岩储集层粒度与软组分含量关系Fig.11 Relationship between particle size and soft component content of the Upper Paleozoic tight sandstone reservoirs in Ordos Basin

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	图12 鄂尔多斯盆地上古生界致密砂岩储集层粒度与渗透率关系图Fig.12 Relationship between particle size and permeability of the Upper Paleozoic tight sandstone reservoirs in Ordos Basin

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	图13 鄂尔多斯盆地上古生界致密砂岩储集层火山岩岩屑含量与溶孔含量关系散点图Fig.13 Scatter diagram showing relationship between volcanic fragments content and dissolved pore content of the Upper Paleozoic tight sandstone reservoirs in Ordos Basin

表5 鄂尔多斯盆地上古生界致密砂岩储集层孔隙含量与储集物性关系 Table5 Relationship between pore content and physical properties of the Upper Paleozoic tight sandstone reservoirs in Ordos Basin

3.3 较粗的沉积物粒度是形成相对高渗储集层的基础

经过笔者近几年的研究, 鄂尔多斯盆地上古生界相对优质储集层主要分布于粗砂岩中。随着粒度的变粗, 软组分(浅变质岩岩屑)含量逐渐减少(图 11), 而渗透率逐渐增大(图 12)。从显微镜下特征来看, 粒度粗, 石英含量高, 孔隙发育(图 9-3); 粒度细, 浅变质岩屑含量高, 碎屑颗粒由于压实作用呈镶嵌状接触, 致密无孔(图 9-4)。

3.4 绿泥石薄膜的形成对保存粒间孔具有重要的意义

早成岩阶段形成的绿泥石薄膜, 一般厚度5~8, μ m, 较均匀地分布于颗粒表面, 垂直颗粒表面生长, 使得溶解于水的二氧化硅缺少结晶核心, 未能形成硅质加大, 从而保存了一部分残余粒间孔(黄思静等, 2004; 刘金库等, 2009; 姚泾利等, 2011)。在研究区上古生界碎屑岩储集层中, 绿泥石薄膜不均匀分布, 但凡有绿泥石薄膜发育的地区和层段, 均具有残余粒间孔(图 9-5), 储集层物性较好。

3.5 局部残余的粒间孔为可溶性组分溶蚀提供了重要的渗流通道

中成岩A— B阶段, 储集层中的可溶性组分大量溶蚀, 但是在溶蚀过程中应有酸性流体的流动通道, 此时, 保存的粒间孔可作为酸性流体有效的渗流通道进行流动, 对可溶性物质进行溶蚀(南珺祥等, 2005)。研究表明, 在鄂尔多斯盆地上古生界致密砂岩气田储集层有粒间孔存在的层段, 溶孔明显发育(表5)。

3.6 适量的可溶性组分是形成溶孔的必要条件

研究区上古生界碎屑岩储集层中可溶性组分主要为火山岩岩屑和凝灰质, 其次为少量的长石、角闪石和辉石等(南珺祥等, 2005), 含量一般在2.0%~20.0%, 最高含量可达到50.0%左右(图 13)。研究发现, 不稳定组分在15.0%以下时, 溶蚀作用较强; 如不稳定组分含量较高, 则溶蚀作用相对较弱(图 9-6)。

3.7 不稳定组分高岭石化形成了大量的晶间孔, 对改善储集层的孔渗条件意义重大

鄂尔多斯盆地上古生界碎屑岩储集层中, 不稳定组分主要有两种成岩演化现象, 一为溶蚀作用, 形成溶孔; 二为高岭石化作用(包洪平等, 2007; 杨华等, 2007)。在研究区上古生界储集层中, 高岭石化作用极其发育, 高岭石结晶良好, 一般呈棒状或蠕虫状, 单个晶体大小可达到20~30 μ m。在石英砂岩中, 蚀变高岭石松散堆积, 晶间孔发育, 蚀变高岭石晶间孔对面孔率的贡献可达到2.0%~3.0%, 是上古生界储集层非常重要的储集空间; 而在岩屑砂岩中, 高岭石虽然结晶粗大, 但堆积相对紧密, 晶间孔不是十分发育, 孔径也相对细小。

4 结论

1)鄂尔多斯盆地上古生界的神木气田、榆林气田及苏里格气田总体上储集层具有孔喉较小、分选较差的特点, 属于典型的致密砂岩气藏。相比而言, 榆林气田山2段的孔隙结构最好, 苏里格气田盒8段次之, 神木气田太原组较差。

2)在低渗透油气田中, 储集层储集空间固然以溶蚀孔为主, 但是, 粒间孔的存在是低渗透储集层中相对优质储集层发育的关键因素。

3)对致密气藏而言, 粒间孔含量高就是产量高。因此在进行储集层评价时应引入粒间孔含量指标作为评价参数之一。

作者声明没有竞争性利益冲突.

参考文献

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[1]	包洪平, 杨奕华, 王晓方, 等. 2007. 同沉积期火山作用对鄂尔多斯盆地上古生界砂岩储集层形成的意义[J]. 古地理学报, 9(4): 397-406. [文内引用:2]
[2]	陈荷立. 1995. 油气运移研究有效途径[J]. 石油与天然气地质, 16(2): 123-131. [文内引用:1]
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[4]	付锁堂, 石小虎, 南珺祥. 2010. 鄂尔多斯盆地东北部上古生界太原组及下石盒子组碎屑岩储集层特征[J]. 古地理学报, 12(5): 609-617. [文内引用:1]
[5]	黄思静, 谢连文, 张萌, 等. 2004. 中国三叠系陆相砂岩中自生绿泥石的形成机制及其与储集层孔隙保存的关系[J]. 成都理工大学学报(自然科学版), 31(3): 273-281. [文内引用:1]
[6]	惠宽洋, 张哨楠, 李德敏, 等. 2002. 鄂尔多斯盆地北部下石盒子组~山西组储集层岩石学和成岩作用[J]. 成都理工学院学报(自然科学版), 29(3): 272-278. [文内引用:1]
[7]	刘金库, 彭军, 刘建军, 等. 2009. 绿泥石环边胶结物对致密砂岩孔隙的保存机制: 以川中—川南过渡带包界地区须家河组储集层为例[J]. 石油与天然气地质, 30(1): 53-58. [文内引用:1]
[8]	吕强, 赵俊兴, 朱平, 等. 2009. 苏里格气田西部山1段储集层特征及影响因素[J]. 天然气工业, 29(3): 13-16. [文内引用:1]
[9]	南珺祥, 解丽琴, 刘绥保, 等. 2005. 鄂尔多斯苏里格气田二叠系低孔低渗储集层成因[J]. 西北大学学报(自然科学版), 35(2): 207-211. [文内引用:3]
[10]	沈玉林, 郭英海, 李壮福. 2006. 鄂尔多斯盆地苏里格庙地区二叠系山西组及下石盒子组盒8 段沉积相[J]. 古地理学报, 8(1): 53-62. [文内引用:1]
[11]	席胜利, 李文厚, 刘新社, 等. 2009. 鄂尔多斯盆地神木地区下二叠统太原组浅水三角洲沉积特征[J]. 古地理学报, 11(2): 187-194. [文内引用:1]
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2007

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包洪平, 杨奕华, 王晓方, 等. 2007. 同沉积期火山作用对鄂尔多斯盆地上古生界砂岩储集层形成的意义[J]. 古地理学报, 9(4): 397-406.

The Upper Paleozoic in the Ordos Basin is mainly made up of a terrigenous clastic sedimentary system. The fluvialdelta facies sandstone reservoirs are widespread and they constitute the main places for the Upper Paleozoic gas accumulation in this area.Owing to the terrigenous matrix filling, diagenetic compaction and cementation, however, most of the primary intergranular pores of the sandstones had been filled up. Therefore, most of the sandstones become too tight to make up effective reservoirs. Through the genetic analyses of the pores of the Upper Paleozoic sandstone reservoirs in the Ordos Basin, it can be suggested that the porous sandstones which are concentrated in parts of the layers, are dominated by the secondary dissolution pores. Further studies show that the secondary dissolution pores were mainly caused by the genetic solution of the pyroclastic components, which had derived from the synsedimentary volcanism and were distributed in the sandstone formations. Therefore, the synsedimentary volcanism controlls the development and distribution of the main Upper Paleozoic sandstone reservoirs of this area. Owing to the easilydissolved component supplied by the intermediate to basic volcanism, it controlls the distribution of porous sandstone reservoirs with higher permeability, while the acid volcanism mainly forms the low permeable sandstone reservoirs, which are dominated by the kaolinite intercrystal pores.

Research Institute of Exploration and Development, PetroChina Changqing Oilfield, Xian710021, Shaanxi

鄂尔多斯盆地上古生界主要为一套陆源碎屑沉积体系，其中广泛发育河流—三角洲相砂岩储集体，是该区上古生界天然气聚集成藏的主要场所。但由于陆源杂基的充填以及成岩压实作用、胶结作用的改造，大部分砂层储集性能都较差而无工业性储集意义。本文通过对鄂尔多斯盆地上古生界砂岩储层孔隙成因的分析，提出在局部层段集中分布的孔隙性砂岩，其孔隙主要为次生溶蚀成因。进一步的研究表明，由同沉积期火山作用形成的、分布于砂岩层中的火山碎屑组分的成岩溶蚀是次生溶孔形成的主要原因。因此，同沉积期火山作用控制了该区上古生界主要砂岩储层的发育和分布。中基性火山作用由于能提供较多的“易溶组分”，从而控制了次生溶孔发育的较高渗透性砂岩储层的分布；而影响更为广泛的酸性火山作用则主要形成以蚀变高岭石晶间孔为主的低渗透性储层。

... 包洪平等,2007 ...

... 二为高岭石化作用(包洪平等,2007 ...

1995

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... 鄂尔多斯盆地上古生界地质历史时期最大埋深可达到4500~5000 m左右(陈荷立,1995 ...

2000

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付金华, 段晓文, 席胜利. 2000. 鄂尔多斯盆地上古生界气藏特征[J]. 天然气工业, 20(6): 16-18.

E'erduosi Basin is a tectonically simple,largescale,multicycle,cratonic basin with an area of 25×10 4 km 2 .The melanic mudstones,coal beds and limestones in the lower part of the CarboniferousPermian of the Upper Paleozoic are of high organic matter content,high thermal evolution level and high gas generating potential,which provided sufficient gas source for forming Paleozoic gas reservoirs;their middle-lower part is a set of sandstones of fluvial facies and delta facies,which are the major reservoirs in the Upper Paleozoic and the argillaceous rocks of alluvial flat facies in their upper part are the good cap-rocks.The structural traps are mainly found around the basin's circumference with developed sandbodies,where activated tectonically during Yanshan epoch;the interior of the basin was stable tectonically and a south-north large-sized lit hological trap was formed in the south-north fluvial-delta complex sandbodies sealed laterally by the argillaceous rocks of fluvial faciec on the west-tilted monocline with dip angles of less than 1°.Therefore,small-sized structural gas reservoirs are mainly formed around the basin's circumference and large-sized lit hologic gas reservoirs in the interior of the basin,which have been proved by the Shenglijing gas reservoir in the fault-flod zone along the west edge of the basin and by the Shan-2 member gas reservoir of the Shanxi Formation,the Lower Permian,at the area of well Shaan-141 on the Yishaan slope.

Research Institute of Exploration and Development, Changqing Oil Field Company

鄂尔多斯盆地是一个构造简单的大型多旋回克拉通盆地,面积约25×10 4 km 2 。上古生界石炭-二叠系下部沉积的暗色泥岩、煤层和石灰岩有机质含量高、热演化程度高、生气能力强,为古生界气藏的形成提供了充足的气源;其中下部为一套河流、三角洲砂岩沉积,是上古生界的主要储层;而其上部的河漫湖相泥质岩为良好盖层。盆地周边在燕山期构造活跃,砂体发育,以构造圈闭为主;盆地内部构造稳定,在倾角不到1°的西倾单斜上,南北展布的河流三角洲复合砂体与侧向河流间湾泥质岩,形成了近南北向的大型岩性圈闭。因此,盆地周边发育以构造控制为主的小型气藏,盆地内部则以大型岩性气藏为主,盆地西缘断褶带胜利井气藏和伊陕斜坡上的陕141井区下二叠统山西组山2段气藏等的存在就反映了这一特征。

... m²(付金华等,2000 ...

2010

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付锁堂, 石小虎, 南珺祥. 2010. 鄂尔多斯盆地东北部上古生界太原组及下石盒子组碎屑岩储集层特征[J]. 古地理学报, 12(5): 609-617.

　鄂尔多斯盆地东北部上古生界太原组及下石盒子组是该区天然气的主力储集层。应用偏光显微镜、环境扫描电镜、恒压压汞以及近几年来发展起来的恒速压汞技术，对该地区上古生界太原组及下石盒子组储集层进行了研究。研究区储集层岩性以粗粒、巨—粗粒岩屑石英砂岩为主，石英砂岩、岩屑砂岩为次。由于成岩作用强烈，残余原生粒间孔基本全部丧失。由于煤系地层提供的大量有机酸以及丰富的可溶性组分，太原组形成了以溶孔为主的储集空间类型，下石盒子组则主要以高岭石晶间微孔为主。太原组及下石盒子组储集层孔隙结构差别巨大，太原组储集层孔径大、孔喉比大，而下石盒子组储集层孔径小，孔喉比接近于１：１，属于较差的孔喉配置。

... 付锁堂等,2010) ...

2004

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... m,较均匀地分布于颗粒表面,垂直颗粒表面生长,使得溶解于水的二氧化硅缺少结晶核心,未能形成硅质加大,从而保存了一部分残余粒间孔(黄思静等,2004 ...

2002

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... 惠宽洋等,2002 ...

2009

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刘金库, 彭军, 刘建军, 等. 2009. 绿泥石环边胶结物对致密砂岩孔隙的保存机制: 以川中—川南过渡带包界地区须家河组储集层为例[J]. 石油与天然气地质, 30(1): 53-58.

The occurrence,forming conditions,and pore-preserving mechanism of chlorite rims in the Upper Triassic Xuejiahe Formation of Baojie area from central to southern Sichuan basin were studied in detail by means of thin section analysis and SEM analysis.The result shows that chlorite rims grew vertically on the grain surface and took the shape of isopachous grain-coating.This kind of cement was formed during the early diagenetic stage and was controlled mainly by depositional environment and provenance conditions.The presence of chlorite rims enhanced the compaction resistance of rock,inhibited quartz overgrowth on detrital-quartz grains,accelerated dissolution and formed excellent pore-throat configuration.Therefore,the chlorite rims played an important role in the preservation of residual primary pores in the tight sandstone reservoirs in the study area.

1. Postgraduate School, Southwest Petroleum University, Chengdu, Sichuan 610500, China; 2. Scientific Research Department, Southwest Petroleum University, Chengdu, Sichuan 610500, China; 3. SINOPEC Northwest Company, Urumqi, Xinjiang 830011, China

用薄片鉴定、扫描电镜等分析手段,对川中-川南过渡带荷包场、界市场地区(简称包界地区)上三叠统须家河组砂岩储层中绿泥石环边胶结物的产状、形成条件及其对储层孔隙的保存机制进行了研究。结果表明,绿泥石环边胶结物以等厚环边方式垂直颗粒表面生长,此类胶结物形成于早成岩阶段,其形成过程主要受沉积环境和物源条件控制;绿泥石环边胶结物的存在提高了岩石的抗压实能力,抑制了石英次生加大,促进了溶蚀作用,形成了有利的孔隙结构。因此,绿泥石环边胶结物对该区致密砂岩储层残余原生孔隙的保存起到了至关重要的作用。

... 刘金库等,2009 ...

2009

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吕强, 赵俊兴, 朱平, 等. 2009. 苏里格气田西部山1段储集层特征及影响因素[J]. 天然气工业, 29(3): 13-16.

The first member of the Lower Permian Shanxi Formation (abbreviated for Shan1 member) is one of the major pay zones in the western Sulige gas field. Its poroperm characteristics are poor due to longterm modification of compaction and cementation. The characteristics and controlling factors on properties of reservoirs in the Shan1 member clastic rocks were studied in respects of petrologic features, pore types and reservoir physical properties, so as to provide a basis for prediction of the lithologic gas reservoirs in the study area. The following understandings are obtained through analyzing various data such as core, cast thin section, SEM and physical properties. The rock types of Shan1 member are dominated by lithic quartz sandstone, quartz sandstone, and lithic sandstone and its poroperm characteristics are poor as the pore types are predominantly of intergranular dissolved pore, intragranular dissolved pore and mould pore. The major factors influencing the properties of the sandstone reservoirs are sedimentary environment, particle features, composition and content of interstitial matter, and the strength of diagenetic transformation. The reservoirs with relatively high quality usually occur in coarse channel sands with high content of quartz and are influenced by diagenesis and interstitial matter.

1. Chengdu University of Technology，Chengdu 610059, China; 2. PetroChina Changqing Oilfield Company, Xi'an 710021,China

下二叠统山西组1段（简称山1段）是苏里格气田西部地区的主力产气层之一，由于该储层经历了长期的压实、胶结等致密化成岩作用改造，故储集物性较差。为了给该区岩性气藏的储层预测提供依据，从储层岩石学特征、孔隙类型和储层物性特征等方面，研究了山1段碎屑岩储层的特征，剖析了影响该储层储集性能的主控因素。通过对岩心、铸体薄片、扫描电镜及物性分析等资料的分析研究，结果表明：①山1段储层岩石类型主要是岩屑石英砂岩、石英砂岩和岩屑砂岩，孔隙类型以粒间溶蚀孔、粒内溶孔及铸模孔为主，物性较差；②影响砂岩储集性能的主控因素为沉积环境、颗粒性质、填隙物成分和含量、成岩作用改造程度；③相对优质储层多出现在石英含量高的河道粗粒砂体中，其分布受成岩作用及填隙物含量的影响。

... 吕强等,2009),在如此巨大的上覆地层压力作用下,软组分强烈变形,部分呈假杂基充填孔隙,完全堵塞喉道(图 9-1),使储集层的孔隙度、渗透率急剧降低(图 10) ...

2005

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... 而局部发育的粒间孔及适量的可溶性组分如火山岩岩屑、凝灰质以及少量的长石的存在是形成相对优质储集层的主要原因(南珺祥等,2005 ...

... B阶段,储集层中的可溶性组分大量溶蚀,但是在溶蚀过程中应有酸性流体的流动通道,此时,保存的粒间孔可作为酸性流体有效的渗流通道进行流动,对可溶性物质进行溶蚀(南珺祥等,2005) ...

... 6 适量的可溶性组分是形成溶孔的必要条件研究区上古生界碎屑岩储集层中可溶性组分主要为火山岩岩屑和凝灰质,其次为少量的长石、角闪石和辉石等(南珺祥等,2005),含量一般在2 ...

2006

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沈玉林, 郭英海, 李壮福. 2006. 鄂尔多斯盆地苏里格庙地区二叠系山西组及下石盒子组盒8 段沉积相[J]. 古地理学报, 8(1): 53-62.

Based on the analysis of drilling data and core, the sedimentary facies of the Shanxi formation to Member 8 of Xiashihezi formation of Permian in Suligemiao oil and gas-bearing area, north Ordos basin, are divided into braided river, meandering river, delta and lake. By the theory of sequence stratigraphy, the Shanxi formation and Member 8 of Xiashihezi formation are divided into 5 sequences, and the sequence stratigraphic framework is set up. The lithofacies paleogeography map is drawn according to system tract. The feature and evolution of the lithofacies paleogeography are discussed in the sequence stratigraphic framework. During the sedimentary period of Shanxi formation, the paleogeography situation was meandering river-delta deposit, which has sedimentary differentiation from north to south. During the sedimentary period of Member 8 of the Xiashihezi formation, the alluvial system removed into the south of study area widely and formed river-delta deposit, in which the braided river is dominant. The channel sand body is high quality reservoir in Suligemiao oil and gas-bearing area, and its development is relative to lowstand system tract. By the palaeogeography mapping in the unit of system tract, the distribution and transferred direction of sedimentary microfacies are shown distinctly. It is an effective method to prospect the high quality reservoir.

School of Resources and Earth Science, China University of Mining and Technology, Xuzhou 221008, Jiangsu

以测井资料和岩心观察为基础，对鄂尔多斯盆地北部苏里格庙含油气区的二叠系山西组及下石盒子组盒八段识别出了辫状河、曲流河、三角洲和湖泊等4种沉积相类型。利用层序地层学原理，将山西组和下石盒子组盒八段划分5个三级沉积层序，建立了苏里格庙含油气区层序地层格架。编制了以体系域为单位的山西组和下石盒子组盒八段沉积期岩相古地理图，探讨了层序地层格架内的山西组和下石盒子组盒八段沉积期岩相古地理特征及演化规律。山西期古地理格局呈南北向相分异的曲流河—三角洲沉积；盒八段沉积期冲积体系大范围向研究区南部迁移，形成了以辫状河沉积为主的河流—三角洲沉积。河道砂体是苏里格庙含油气区有利的砂质储集体类型，主要发育在低位体系域。实践表明，以体系域为单位编制的岩相古地理图，可以清楚地展示不同沉积时期的沉积微相展布与迁移变化，是有利储层预测的一种有效方法。

... 沈玉林等,2006 ...

2009

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席胜利, 李文厚, 刘新社, 等. 2009. 鄂尔多斯盆地神木地区下二叠统太原组浅水三角洲沉积特征[J]. 古地理学报, 11(2): 187-194.

The Taiyuan Formation is dominated by shallow water delta deposits in a north uplifting and south inclining tectonic setting. Its characters are as follows: when the sedimentscarrying river flew into the seawater， due to the different density between river and seawater， and a little latteral diffusion， the delta front would move along the seabed rapidly， and the subaqueous distributary channel extended a long distance. The study area is characterized by a gentle slope and shallow water setting， thus the delta plain extended forward and decreased the topographic slope furthermore which led to the decrease of energy of fluids carrying the sediments and most of the sediments were deposited in the distributary channel in the delta plain. Otherwise， due to the shallow water setting， mouth bar and sheetlike sandbodies of delta front were easily exposed by the transgressive subaqueous distributary channel and were difficult to be preserved. Distributary channel was well developed， prodelta was relatively not well developed and delta front was dominated by subaqueous distributary channel deposits. Distributary channel and subaqueous distributary channel usually strongly eroded the underlying sediments， including the sediments deposited during early periods even the deep water sediments including marine sediments. During the abandonment period of delta， sediments of delta front were usually rebuilt by tidal action. Distributary channel sandbodies of delta plain and subaqueous distributary channel of delta front are distributed in belt which are the favorable targets for natural gas exploration.

鄂尔多斯盆地神木地区太原组是在北隆南倾的古地形背景下形成的以浅水三角洲为主的充填沉积。携带沉积物的河流进入海水后，由于河水与海水之间存在着较大的密度差异、侧向扩散较少，其三角洲前缘沿着海底继续向前快速推进，使水下分流河道延伸较远。研究区地形坡度平缓、水体浅，三角洲平原向前推进并进一步降低了地形坡度，从而减弱了携带沉积物的流体的动能，使得大部分沉积物在三角洲平原的分流河道中沉积下来。同时因水体浅，河口坝、席状砂等前缘沉积物常遭受进积的水下分流河道的冲刷和侵蚀而难以保存。研究区三角洲平原分流河道沉积极为发育，前三角洲相对不发育，三角洲前缘也以水下分流河道沉积为主。分流河道、水下分流河道常对下伏沉积物强烈冲刷，切割先期的沉积物乃至包括海相沉积物在内的深水沉积物。在三角洲废弃期，三角洲前缘沉积物常被潮汐作用改造。三角洲平原分流河道及三角洲前缘水下分流河道砂体呈带状分布，是天然气勘探的有利目标。

... 席胜利等,2009 ...

2007

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杨华, 杨奕华, 石小虎, 等. 2007. 鄂尔多斯盆地周缘晚古生代火山活动对盆内砂岩储集层的影响[J]. 沉积学报, 25(4): 526-534.

Upper Paleozoic natural gas reservoir of Ordos Basin consists of lowpermeability sandstone which bears typical secondary porosity. After studying secondary porosity forming cause, it is turned out that there is some direct relation between formation of all kinds of dissolution porosity and dissolution and erosion of volcanic material. Based on the study of petrology, the observation of volcanic material composition, construction and structure, the state and secondary change, we can reach the conclusion that these volcanic materials has the characteristics of simultaneous sedimentation. Combing the formal achievements about simultaneous volcano eruptiverock on basin edge, there is causeeffect relation, which showing volcanic material of the sandstone comes from the simultaneous sedimentary volcanic eruption, which confirms that important geological events in Basinorogen coupling period have great influence on interbasin sedimentation. Not only the simultaneous volcanic material changes the composition of the sandstone, but also offers the dissolution matter for the formation of secondary porosity in these sandstones. The dissolution of volcanic material, with largely unsteady physical and chemical characteristics, led to the formation of dissolution porosity in crystalfragment, in rockfragment, and in ashfragment, as well as eroded kaolinite and chlorite intercrystal porosity in diagenetic period. Meanwhile, remnant, erosion of volcanic material and dissolution differences lead to the heterogeneous reservoir.

Changqing Oilfield Company, PetroChina, Xi’an 710021

鄂尔多斯盆地上古生界天然气储集体是一套以次生孔隙为主的低渗透砂岩。通过次生孔隙成因研究发现，各种溶蚀孔隙的形成与砂岩中火山物质和硅酸盐碎屑颗粒的溶蚀、蚀变关系密切。通过储层岩石学研究，对火山物质成分、结构构造、物态、次生变化等特征精细观察表明，这些火山物质具有同沉积的特点，即来源于盆地周缘同期的火山喷发。这些同沉积火山物质不仅改变了储层砂岩的物质成分，而且为储层次生孔隙的形成提供了溶蚀母质，形成了晶屑溶孔、岩屑溶孔、灰屑溶孔以及蚀变高岭石、绿泥石晶间孔，在原生孔隙基本消失的砂岩中形成了以次生孔隙为主的砂岩储层。同时，火山物质的残存、蚀变和溶蚀的差异使储层表现出强烈非均质性。

... 杨华等,2007) ...

2011

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姚泾利, 王琪, 张瑞, 等. 2011. 鄂尔多斯盆地华庆地区延长组长6砂岩绿泥石膜的形成机理及其环境指示意义[J]. 沉积学报, 29(1): 72-77.

〓With thin section analysis and scanning electron microscopic analysis, the diagenetic phenomenon of Yanchan Formation sandstone in the Ordos basin were systematically studied, and it shows that chlorite film was the important diagenetic phenomenon in this area. Depending on the studies relevant to the features including occurrence, structural characteristics, relations between other diagenetic minerals of sandstones in this area, the formation mechanism was discussed in detail. Chlorite rim had some relevance with the original porosity of reservoirs, its formation had more closely relationship with hydrodynamic conditions during the contemporaneous deposition. They belonged to a mark of water power conditions for they occur mainly in the subaqueous distributary channel and mouth bar in the deltaic front, and had strong environmental specificity; chlorite rim had double layer structure in which isopachous rim cement of internal layer was relative dense, and formed during the early diagenetic stage. Outerlayer authigenic chlorite grown on the rim surface vertically with better crystal form was formed during the late diagenetic stage; chlorite film was of a limited ability to protect the sandstone porosity. The reason for this is that the porosity of sandstones with chlorite clay rim was better mainly depended on the petrological characteristics of sedimentary sandstones under strong hydrodynamic condition. It had little relation with the chlorite clay rim. So the formation model of chlorite clay rim was put forward. It was considered that the formation of the chlorite film experienced five steps: sedimentary stage of original particles, stage of clay adsorption and film formation on the surface of original particles, early compaction stage of particles, stage of rim chloritization, authigenic chlorite forming stage; In view of this, the sedimentary sandstone reservoirs that had chlorite clay rims under strong hydrodynamic conditions should be the target in the process of oil exploration. 

Research Institute of Exploration and Development, PetroChina Changqing Oilfield Company, Xi'an 710021

通过薄片鉴定和扫描电镜等技术手段，对鄂尔多斯盆地延长组砂岩的成岩现象进行了分析，发现绿泥石黏土膜为该区重要的成岩现象。在对该区砂岩绿泥石黏土膜的产状、结构特征及与其它成岩矿物之间的关系等特征分析的基础上，对其形成机理进行了详细讨论，认为绿泥石黏土膜与储层原生孔隙具有一定的关联作用，其形成与同沉积时期水动力条件关系更为密切，属于强水动力沉积条件的一种标志，主要发育于三角洲前缘水下分流河道和河口坝等微相中，具有较强的环境专属性；绿泥石黏土膜具有双层结构，里层的等厚环边胶结物相对致密，是早期成岩阶段形成的。外层的自生绿泥石垂直于环边表层生长，晶形较好，是晚期成岩阶段形成的；绿泥石黏土膜保护砂岩孔隙能力有限。绿泥石黏土膜发育的砂体物性较好，主要是由于强水动力条件下沉积的砂体本身岩石学特性所决定，与绿泥石黏土膜关系不大。由此提出绿泥石黏土膜形成模式，认为其形成经历了5个阶段：原始颗粒沉积阶段、原始颗粒表面黏土吸附成膜阶段、颗粒初期压实阶段、环边绿泥石化阶段和自生绿泥石形成阶段。鉴于此，在华庆地区延长组石油勘探过程中，应寻找绿泥石黏土膜相对发育的强水动力条件下的沉积砂岩储集体。

... 姚泾利等,2011) ...