天然气地球科学 ›› 2022, Vol. 33 ›› Issue (2): 288–296.doi: 10.11764/j.issn.1672-1926.2021.11.008

• 非常规天然气 • 上一篇    下一篇

鄂尔多斯盆地陇东地区太原组铝土岩储层特征及形成机理

南珺祥1,2(),柳娜1,2(),王邢颖1,2,解古巍1,2,尹鹏1,2,杨艳宁3   

  1. 1.低渗透油气田勘探开发国家工程实验室,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.中国石油长庆油田分公司第六采油厂,陕西 西安 710200
  • 收稿日期:2021-09-15 修回日期:2021-11-14 出版日期:2022-02-10 发布日期:2022-02-25
  • 通讯作者: 柳娜 E-mail:njx_cq@petrochina.com.cn;liun1_cq@petrochina.com.cn
  • 作者简介:南珺祥(1968-),男,甘肃会宁人,高级工程师,博士,主要从事油气沉积地质学及储层研究.E-mail:njx_cq@petrochina.com.cn.
  • 基金资助:
    中国石油长庆油田分公司“非常规气藏勘探潜力评价技术研究”项目(2021DA02)

Characteristics and formation mechanism of bauxite reservoir in Taiyuan Formation, Longdong area, Ordos Basin

Junxiang NAN1,2(),Na LIU1,2(),Xingying WANG1,2,Guwei XIE1,2,Peng YIN1,2,Yanning YANG3   

  1. 1.National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields,Xi’an 710018,China
    2.Research Institute of Exploration and Development,PetroChina Changqing Oilfield Company,Xi’an 710018,China
    3.No. 6 Oil Production Plant,PetroChina Changqing Oilfield Company,Xi’an 710200,China
  • Received:2021-09-15 Revised:2021-11-14 Online:2022-02-10 Published:2022-02-25
  • Contact: Na LIU E-mail:njx_cq@petrochina.com.cn;liun1_cq@petrochina.com.cn
  • Supported by:
    The Project of PetroChina Changqing Oilfield Company(2021DA02)

摘要:

国内外鲜见公开报道将铝土岩作为天然气储层进行研究。近年来,勘探实践证明,鄂尔多斯盆地陇东地区太原组铝土岩含气性好,部分探井已产出高产工业气流,因此亟需加强铝土岩储层基础地质研究。应用铸体薄片、X?射线衍射、扫描电镜、恒压压汞及核磁共振等技术对研究区铝土岩储层特征及形成机理进行研究。结果表明:研究区铝土岩(矿)沉积特征与华北地区在成因上一致,均为内源机械—化学沉积型铝土岩,层理构造发育,其结构可分为砂砾屑结构、豆—鲕状结构、晶粒(粉晶)结构等。铝土岩自下到上可分为5段,其中:A段(铁质铝土岩段)含有丰富的黄铁矿;B段(铝土质泥岩段)黏土矿物含量较高;C段(铝土岩段)硬水铝石含量可达90%以上;D段(含硅铝土岩段)粉晶自生硅质岩发育;E段(炭质泥岩和煤岩段)富含有机质。储集层段主要分布于C段中上部,即多孔铝土岩段。储层孔隙的形成主要经历3个阶段:准同生期是孔隙形成的主要时期,腐殖酸与大气淡水淋滤作用形成溶孔;埋藏成岩期也是孔隙形成的较为重要时期,此时晶体结构疏松、呈层状分布的一水软铝石转化为结构紧密、呈板柱状分布的硬水铝石,形成晶间孔,约占可见孔的10%以上;成岩期炭质泥岩及煤层成熟排出的有机酸使溶孔及晶间溶孔扩大,形成扩大的溶蚀孔及晶间溶孔,对储集条件具有一定的改善作用。研究区铝土岩储集性能良好,平均孔隙度为14.67%、平均渗透率为5.57×10-3 μm2,是天然气良好的储集层。铝土岩脆性指数在90%以上,具有高杨氏模量(36.4 GPa)、高泊松比(0.35)特征,适于储层压裂改造。

关键词: 鄂尔多斯盆地, 陇东地区, 太原组, 铝土岩储层, 形成机理

Abstract:

Bauxite as a natural gas reservoir has not been reported publicly at home and abroad. In recent years, exploration has proved that the gas-bearing property of bauxite in Lower Carboniferous is good, and high-yield industrial gas flow has been found in some exploratory wells. Therefore, it is urgent to study the basic geology of bauxite reservoir. The characteristics and formation mechanism of bauxite reservoir in study area was determined by thin section, X-ray diffraction, scanning electron microscopy, constant-pressure mercury injection and nuclear magnetic resonance analyses. The results show that the sedimentary characteristics of bauxite in the study area are the same as those in the northern China area. They are all internal mechanic-chemical sedimentary bauxite with mechanical transport in some parts. The bedding structure is well developed, and the rock texture can be divided into sand-gravel texture, pisolitic-oolitic texture, clay crystal texture, grain (powder crystal) texture and so on. From the bottom to the top, it can be divided into five sections: Section A (Fe-bearing section), section B (bauxitic mudstone section), section C (bauxite section), section D (siliceous bauxite section), and section E (carbonaceous mudstone or coal line section). The mineral composition of each section is obviously different. There are rich pyrite in section A, high content of clay mineral in section B, and over 90% content of diaspore in section C, the powder crystal authigenic siliceous rocks are developed in section D, and the organic matter is rich in section E. The reservoir is mainly distributed in the middle and upper part of C, namely the porous bauxite section. The formation of reservoir pores goes through three stages: the dissolved pores formed by the leaching of humic acid and atmospheric fresh water in penecontemporaneous period are the main stage of pore formation, accounting for 80% of the total visible pores; burial diagenesis stage is also an important period for pore formation, at this time, the layered diaspore with loose crystal structure is transformed into the dense plate-columnar diaspore, which forms intergranular pores accounting for more than 10% of the visible pores; the organic acids discharged from carbonaceous mudstone and coal seam can enlarge the dissolution pores and form intergranular dissolution pores, which can improve the reservoir conditions to some extent. The reservoir performance of the study area is good, and the average porosity is 14.67%, the average permeability is 5.57×10-3 μm2, which is a good reservoir of natural gas. The brittleness index is more than 90%, which is much higher than that of shale oil and shale gas in the basin. It has the geological characteristics of strong fracturing ability with high brittleness index (>90%), high Young's modulus (36.4 GPa) and high Poisson's ratio (0.35) which means it is suitable for fracturing.

Key words: Ordos Basin, Longdong area, Taiyuan Formation, Bauxitic, Formation mechanism

中图分类号: 

  • TE122.2

图1

陇东地区太原组铝土岩平面分布①"

图2

陇东地区太原组铝土岩沉积序列"

图3

陇东地区铝土岩沉积序列典型岩心照片(a)L58井,4 051.90 m,黄铁矿结核,铁质铝土岩,A段;(b)L58井,4 055.78 m,砂屑、豆鲕结构,硬水铝石含量39.0%,伊利石+绿泥石总含量53.5%,铝土质泥岩,B段;(c) L58井,4 048.85 m,土状多孔铝土岩,C段下;(d)L58井,4 048.75 m,多孔铝土岩,孔洞发育,C段中上;(e)L58井,4 039.30 m,含硅铝土岩,D段;(f)L58井,4 036.76 m,煤岩,E段"

图4

陇东地区铝土岩储层孔隙组合特征(a)豆—鲕状硬水铝石岩,L47井,4 114.00 m,豆鲕溶孔,示顶底构造,底部泥晶硬水铝石,顶部针状硬水铝石,纹层具有绕过鲕粒特征;(b)残余豆—鲕状硬水铝石岩,L58井,4 049.16 m,豆鲕壁溶孔,纹层绕过粒屑;(c)泥晶砂砾屑硬水铝石岩,L58井,4 050.76 m,粒间溶孔及微裂缝;(d)残余砂砾屑硬水铝石岩,L58井,4 047.52 m,晶间溶孔(针孔);(e)粉晶硬水铝石,CH3-25-11井,3 806.65 m,硬水铝石晶间孔及晶间溶孔;(f)微亮晶砂屑硬水铝石岩,L47井,4 100.00 m,豆鲕间形成的硬水铝石晶间孔;(g)泥质硬水铝石岩,L58井,4 044.99 m,局部可见准同生期砂屑,纹层发育;(h)藻黏结粉晶硬水铝石岩,L58井,4 048.75 m,凝块石成岩早期硬水铝石化,无溶蚀,基质藻黏结结构,硬水铝石化过程中有溶蚀作用"

表1

陇东地区太原组铝土岩X-射线衍射分析数据表及脆性指数"

井 号岩性段深度/m矿物含量/%脆性指数/%
石英长石方解石白云石铁白云石菱铁矿黏土黄铁矿硬水铝石其他
L47D4 094.0053.00.338.50.31.54.31.01.154.3
C4 114.00~4 116.001.00.20.29.33.082.34.189.8
B4 119~4 120.000.60.20.25.234.10.550.29.156.2
A4 123.000.70.00.565.47.36.919.29.4
L58C4 045.552.30.289.77.897.5
4 047.100.70.193.16.199.3
4 048.16~4 048.300.10.10.695.93.399.3

图5

L58井太原组铝土岩储层物性纵向分布特征"

图6

陇东地区铝土岩孔隙度与渗透率相关图"

图7

陇东地区“多孔铝土岩段”核磁共振测试T2图谱注:L58井,4 045.9 0m ,孔隙度20.7%,渗透率0.44×10-3 μm2;L58井,4 048.30 m,孔隙度19.2%,渗透率3.99×10-3 μm2"

图8

陇东地区“多孔铝土岩段”毛管压力曲线"

图9

陇东地区铝土岩孔隙形成模式"

表2

陇东地区铝土岩储层孔隙组合统计"

孔隙类型溶孔晶间孔晶间溶孔微裂缝
面孔率/%3.50.60.30.1
占比/%77.813.36.72.2
1 HORBE A, COSTA M. Geochemical evolution of a lateritic Sn-Zr-Th-Nb-Y-REE-bearing ore body derived from apogranite: The case of Pitinga, Amazonas-Brazil[J].Journal of Geochemical Exploration,1999,66:339-351.
2 MORDBERG L E. Mineralogy and geochemistry of trace elements in bauxites: The Devonian Schugorsk deposit, Russia[J].Mineralogical Magazine,2001,65(1):81-101.
3 EMMERICH K, SMYKATZ-KLOSS W. Exothermic effects in soils during thermal analysis[J].Clay Minerals,2002,37:575-582.
4 LASKOU M, MARGOMENOU-LEONIDOPOULOU G, BALEK V. Thermal characterization of bauxite samples[J]. Journal of Thermal Analysis and Calorimetry,2006,84(1):141-146.
5 CORNELL R M, SCHWERTMANN U. The Iron Oxides: Structure,Properties,Reactions,Occurrences and Uses[M].Berlin: Wiley-VCH,2006:1-703.
6 MAMELI P, MONGELLI G, OGGIANO E D. Geological, geochemical and mineralogical features of some bauxite deposits from Nurra(western Sardinia,Italy): Insights on conditions of formation and parental affinity[J].International Journal of Earth Science,2007,96(5):887-902.
7 BOGATYREV B A, ZHUKOV V V, TSEKHOVSKY Y G. Formation conditions and regularities of the distribution of large and super large bauxite deposits[J].Lithology and Mineral Resources,2009,44(2):135-151.
8 杜远生,余文超.沉积型铝土矿的陆表淋滤成矿作用:兼论铝土矿床的成因分类[J].古地理学报,2020,22(5):812-826.
DU Y S, YU W C. Subaerial leaching process of sedimentary bauxite and the discussion on classifications of bauxite deposits[J]. Journal of Palaeogeography,2020,22(5):812-826.
9 孟祥化,葛铭,肖增起.华北石炭纪含铝建造沉积学研究[J].地质学报,1987(2):182-197.
MENG X H, GE M, XIAO Z Q. Study on the sedimentology of the Carboniferous allite-bearing formation(sequence) of North China[J]. Acta Geologica Sinica,1987(2):182-197.
10 温同想.河南石炭纪铝土矿地质特征[J].华北地质矿产杂志,1996,11(4):491-511.
WEN T X. Geological characteristics of Carboniferous bauxite in Henan Province[J]. Journal of Geology & Mineral Resource in North China,1996,11(4):491-511.
11 BARRDOSSY G, ALEVA G J J. Lateritic Bauxites[M].Amsterdam: Elsevier,1990:1-504.
12 DARGENIO B, MINDSZENTY A. Bauxites and related paleokarst: Tectonic and climatic event markers at regional unconformities[J].Eclogae Geologicae Helvetiae,1995,88(3):453-499.
13 袁珍,武富礼,封蓉,等.鄂尔多斯延长气田铝土岩分布规律及其地质意义[J].西安科技大学学报,2016,36(6):843-848.
YUAN Z, WU F L, FENG R, et al. The distribution rule and its geological significance of Bauxite in Yanchang gas field of Ordos Basin[J]. Journal of Xi'an University of Science and Technology,2016,36(6):843-848.
14 杨俊杰,裴锡古.中国天然气地质学[M].北京:石油工业出版社,1996.
YANG J J, PEI X G. Natural Gas Geology of China[M].Beijing: Petroleum Industry Press,1996.
15 张亚男,张莹华,吴慧,等.黔北务正道地区铝土矿鲕粒矿石中鲕粒的微区元素地球化学特征及其成矿意义[J].地质科技情报,2013,32(1):62-70.
ZHANG Y N, ZHANG Y H, WU H, et al. Microscopic geochemical characteristics of oolite in oolitic bauxite ores from Wuchuan-Zheng’an-Daozhen area in the northern Guizhou Province and their metallogenic significance[J].Geological Science and Technology Information,2013,32(1):62-70.
16 余文超,杜远生,周琦,等.黔北务川—正安—道真地区铝土矿系中生物标志物及其地质意义[J].地质科技情报,2012,14(5):651-662.
YU W C, DU Y S, ZHOU Q, et al. Biomarkers of bauxite-bearing strata and its geological significance in Wuchuan-Zheng'an-Daozhen area, northern Guizhou Province[J]. Geological Science and Technology Information,2012,14(5):651-662.
17 MONGELLI G, BUCCIONE R, GUEGUEN E, et al. Geochemistry of the Apulian allochthonous karst bauxite, southern Italy: Distribution of critical elements and constraints on Late Cretaceous Peri-Tethyan palaeogeography[J].Ore Geology Reviews,2016,77:246-259.
18 TEMUR S, KANSUN G. Geology and petrography of the Masatdagi diasporic bauxites, Alanya, Turkey[J].Journal of Asian Earth Sciences,2006,27(4):512-522.
19 张晨晨,王玉满,董大忠,等.四川盆地五峰组—龙马溪组页岩脆性评价与“甜点层”预测[J].天然气工业,2016,36(9):51-60.
ZHANG C C, WANG Y M, DONG D Z, et al. Evaluation of the Wufeng-Longmaxi shale brittleness and prediction of “sweet spot layers” in the Sichuan Basin[J]. Natural Gas Industry,2016,36(9):51-60.
20 刘学飞,王庆飞,李中明,等.河南铝土矿矿物成因及其演化序列[J].地质与勘探,2012,48(3):449-459.
LIU X F, WANG Q F, LI Z M, et al. Mineral genesis and evolutionary sequence of the bauxite deposits in Henan Province[J]. Geology and Exploration,2012,48(3):449-459.
21 布申斯基Г И. 铝土矿地质学[M].北京:地质出版社,1984.
BUSHINSKY Г И. Bauxite GeoLogy[M].Beijing: The Geological Publishing House,1984.
[1] 党文龙, 高岗, 刘建平, 姚泾利, 刚文哲, 杨尚儒, 段延娟, 张莉莉. 鄂尔多斯盆地奥陶系马家沟组盐下天然气成因类型及来源[J]. 天然气地球科学, 2022, 33(2): 207-217.
[2] 陈俊霖, 王朋, 郜元元, 李开, 杨明, 张家强, 李家程, 李树同. 多元逐步回归法在致密砂岩储层矿物与孔隙度关系分析中的应用[J]. 天然气地球科学, 2021, 32(9): 1372-1383.
[3] 王万春, 吉利明, 宋董军, 张东伟, 吕成福, 苏龙. 不同比例砂岩/油页岩热模拟实验滞留油量及其地质意义——以鄂尔多斯盆地三叠系延长组7段为例[J]. 天然气地球科学, 2021, 32(8): 1142-1150.
[4] 刘显阳, 李士祥, 郭芪恒, 周新平, 刘江艳. 鄂尔多斯盆地延长组长73亚段泥页岩层系岩石类型特征及勘探意义[J]. 天然气地球科学, 2021, 32(8): 1177-1189.
[5] 席胜利, 莫午零, 刘新社, 张雷, 李剑, 黄正良, 王民, 张春林, 朱秋影, 言语, 周能武. 鄂尔多斯盆地西缘奥陶系乌拉力克组页岩气勘探潜力——以忠平1井为例[J]. 天然气地球科学, 2021, 32(8): 1235-1246.
[6] 于洲, 周进高, 李程善, 宋晓娇, 罗超, 吴兴宁, 吴东旭, 胡琮. 鄂尔多斯盆地西缘奥陶纪克里摩里期—乌拉力克期构造—岩相古地理特征[J]. 天然气地球科学, 2021, 32(6): 816-825.
[7] 郭轩豪, 谭成仟, 赵军辉, 赵信, 王进. 成岩作用对致密砂岩储层微观结构的影响差异[J]. 天然气地球科学, 2021, 32(6): 826-835.
[8] 陈诚, 齐宇, 喻梓靓, 王波. 浅水三角洲河道砂体叠置关系的地震识别——以鄂尔多斯盆地东缘临兴S区为例[J]. 天然气地球科学, 2021, 32(5): 772-780.
[9] 王华, 崔越华, 刘雪玲, 强阵阵, 王世成. 致密砂岩气藏多层系水平井立体开发技术——以鄂尔多斯盆地致密气示范区为例[J]. 天然气地球科学, 2021, 32(4): 472-480.
[10] 刘桂珍, 高伟, 尉加盛, 唐文. 混积层系沉积、层序特征——以鄂尔多斯盆地高桥地区本溪组为例[J]. 天然气地球科学, 2021, 32(3): 382-392.
[11] 郭广山, 柳迎红, 李林涛. 鄂尔多斯盆地东缘北段煤层含气量变化规律及控制因素[J]. 天然气地球科学, 2021, 32(3): 416-422.
[12] 付金华, 郭雯, 李士祥, 刘显阳, 程党性, 周新平. 鄂尔多斯盆地长7段多类型页岩油特征及勘探潜力[J]. 天然气地球科学, 2021, 32(12): 1749-1761.
[13] 刘显阳, 杨伟伟, 李士祥, 孙林, 常睿. 鄂尔多斯盆地延长组湖相页岩油赋存状态评价与定量表征[J]. 天然气地球科学, 2021, 32(12): 1762-1770.
[14] 李士祥, 周新平, 郭芪恒, 刘建平, 刘江艳, 李树同, 王博, 吕奇奇. 鄂尔多斯盆地长73亚段页岩油可动烃资源量评价方法[J]. 天然气地球科学, 2021, 32(12): 1771-1784.
[15] 李树同, 李士祥, 刘江艳, 杨鸣一, 陈俊霖, 张珊, 崔德艺, 李家程. 鄂尔多斯盆地长7段纯泥页岩型页岩油研究中的若干问题与思考[J]. 天然气地球科学, 2021, 32(12): 1785-1796.
Viewed
Full text


Abstract

Cited

  Shared   
  Discussed   
[1] 任以发. 微量烃分析在井中化探录井中的应用[J]. 天然气地球科学, 2005, 16(1): 88 -92 .
[2] 廖成君. VSP技术在锦612复杂断块油藏开发部署研究中的应用[J]. 天然气地球科学, 2005, 16(1): 117 -122 .
[3] 马立祥. 岩石物理流动单元的概念及其研究现状[J]. 天然气地球科学, 2000, 11(2): 30 -36 .
[4] 赵生才;. 香山科学会议第268次学术讨论会“中国煤层气资源及产业化”召开[J]. 天然气地球科学, 0, (): 6 .
[5] 倪金龙;夏斌;. 济阳坳陷坡折带组合类型及石油地质意义[J]. 天然气地球科学, 2006, 17(1): 64 -68 .
[6] 王杰,刘文汇,秦建中,张隽. 中国东部幔源气藏存在的现实性与聚集成藏的规律性[J]. 天然气地球科学, 2007, 18(1): 19 -26 .
[7] 程同锦,朱怀平,陈浙春. 孔雀1井剖面地球化学特征与烃类的垂向运移[J]. 天然气地球科学, 2006, 17(2): 148 -152 .
[8] 唐友军,文志刚,窦立荣,徐佑德. 一种估算原油成熟度的新方法[J]. 天然气地球科学, 2006, 17(2): 160 -162 .
[9] 张宝,包建平,江凤梅. 三塘湖盆地侏罗系煤岩倾油倾气性探讨[J]. 天然气地球科学, 2006, 17(2): 183 -186 .
[10] 尹太举,张昌民,王寿平,李中超 . 濮53块开发概念模拟[J]. 天然气地球科学, 2006, 17(2): 201 -205 .