0 引言
1 地质背景
2 样品与实验
3 岩石学特征
图3 冷湖七号地区下干柴沟组上段碎屑岩结构特征(a) 仙西1井,4 113.34 m,灰白色粗砂岩夹黑色粉砂岩;(b) 仙西1井,4 208.82 m,灰色细砂岩;(c) 仙西1井,4 212.82 m,灰色含砾粗砂岩;(d) 仙西1井,4 113.78 m,含灰中细粒长石质岩屑砂岩,早期碳酸盐胶结物;(e) 仙西1井,4 213.02 m,不等粒岩屑质长石砂岩,铁方解石胶结发育;(f) 仙西1井,4 116.70 m,含灰中粗粒长石质岩屑砂岩,方解石充填于次生溶蚀孔隙;(g) 仙西1井,4 111.51 m,丝状伊利石,伊/蒙混层等黏土矿物充填在颗粒间及颗粒表面;(h) 仙西1井,4 209.77 m,方解石填隙,石英自生加大,颗粒表面发育伊/蒙混层黏土矿物;(i) 仙西1井,4 212.14 m,蜂窝状自生绿泥石与伊/蒙混层矿物 Fig.3 Structural characteristics of clastic rocks of the upper section of the Lower Ganchaigou Formation in Lenghu No.7 region |
表1 冷湖七号地区下干柴沟组上段全岩和黏土矿物X-射线衍射分析结果Table 1 X-ray diffraction of whole rock and clay minerals of the upper section of the Lower Ganchaigou Formation in Lenghu No.7 region |
深度/m | 层 位 | 矿物种类和含量/% | 黏土总量 /% | 黏土矿物相对含量/% | 混层比/% | ||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
石英 | 钾长石 | 钠长石 | 方解石 | 硬石膏 | S | I/S | I | K | C | I/S | |||
4 111.51 | 下干柴沟组上段 | 68.2 | 6.0 | 9.4 | 3.8 | / | 12.6 | / | 32 | 44 | / | 24 | 6 |
4 111.75 | 47.6 | 6.0 | 16.2 | 20.3 | / | 9.9 | / | 19 | 47 | / | 34 | 10 | |
4 112.11 | 47.4 | 9.5 | 10.3 | 11.4 | / | 21.3 | / | 11 | 72 | / | 17 | 12 | |
4112.64 | 69.9 | 2.2 | 7.1 | 7.9 | 0.8 | 12.1 | / | 26 | 54 | / | 20 | 5 | |
4 112.99 | 45.1 | 3.9 | 12.1 | 16.6 | / | 22.4 | / | 7 | 80 | / | 13 | 9 | |
4 113.65 | 49.7 | 9.9 | 9.9 | 14.5 | / | 16.0 | / | 15 | 69 | / | 16 | 10 | |
4 114.16 | 46.7 | 9.9 | 9.9 | 14.3 | 1.1 | 18.1 | / | 30 | 61 | / | 9 | 10 | |
4 114.82 | 42.8 | 9.5 | 17.1 | 6.4 | / | 21.8 | / | 32 | 42 | / | 26 | 12 | |
4 115.27 | 70.2 | 3.6 | 8.4 | 5.2 | / | 12.7 | / | 25 | 58 | / | 17 | 8 | |
4 115.60 | 60.7 | 10.3 | 14.1 | 4.1 | / | 10.8 | / | 22 | 51 | / | 27 | 5 | |
4 115.72 | 64.7 | 5.2 | 11.9 | 2.9 | / | 15.4 | / | 11 | 62 | / | 27 | 7 | |
4 116.04 | 68.1 | 3.6 | 10.0 | 5.1 | / | 13.3 | / | 51 | 31 | / | 18 | 14 | |
4 116.34 | 53.9 | 14.9 | 12.6 | 6.4 | / | 12.3 | / | 38 | 41 | / | 21 | 15 | |
4 207.72 | 39.4 | 11.9 | 24.5 | 6.6 | / | 6.9 | / | 10 | 40 | / | 50 | 10 | |
4 208.32 | 52.4 | 8.1 | 17.6 | 11.8 | / | 6.6 | / | 9 | 35 | / | 56 | 8 | |
4 209.04 | 49.2 | 5.1 | 9.7 | 17.6 | / | 18.5 | / | 5 | 55 | / | 40 | 8 | |
4 209.52 | 58.5 | 5.1 | 13.5 | 12.3 | / | 10.7 | / | 18 | 36 | / | 46 | 21 | |
4 210.43 | 56.0 | 4.5 | 20.7 | 8.1 | / | 10.7 | / | 26 | 22 | / | 52 | 8 | |
4 210.97 | 63.3 | 11.4 | 12.7 | 6.0 | / | 6.6 | / | 13 | 39 | / | 48 | 14 | |
4 211.18 | 49.5 | 8.5 | 19.1 | 7.9 | / | 15.0 | / | 9 | 37 | / | 54 | 8 | |
4 211.82 | 49.2 | 7.3 | 8.1 | 5.4 | / | 29.9 | / | 20 | 46 | / | 34 | 8 | |
4 212.32 | 47.2 | 7.5 | 11.6 | 5.6 | / | 24.5 | / | 29 | 18 | / | 53 | 9 | |
4 212.93 | 60.0 | 8.2 | 7.4 | 12.5 | / | 11.9 | / | 17 | 35 | / | 48 | 12 | |
4 213.57 | 67.4 | 6.8 | 11.9 | 5.7 | 8.2 | / | 23 | 19 | / | 58 | 5 | ||
4 214.61 | 57.0 | 12.7 | 13.3 | 8.8 | / | 8.3 | / | 23 | 30 | / | 47 | 8 | |
4 215.68 | 36.5 | 1.3 | 9.4 | 16.8 | / | 32.6 | / | 17 | 58 | / | 25 | 9 | |
平均值 | 54.6 | 7.4 | 12.6 | 9.4 | 1.0 | 15.0 | / | 20.7 | 45.5 | / | 33.8 | 9.7 |
标准:SY/T5163-2010。S+I/S+I+K+C+C/S=101或99为小数修约为整数所致,非数据偏差。按有关标准规定,将混层比大于70%的I/S划入蒙脱石。说明:S代表蒙脱石;I/S代表伊/蒙混层;I代表伊利石;K代表高岭石;C代表绿泥石;C/S代表绿/蒙混层。混层比,例如20%,表明伊/蒙或绿/蒙混层中蒙脱石含量为20% |
4 结果分析
4.1 成岩作用
4.2 沉积微相
4.3 沉积环境
表2 冷湖七号地区下干柴沟组上段元素测试分析结果Table 2 Elements analysis results of the upper section of the Lower Ganchaigou Formation in Lenghu No.7 region |
深度/m | 岩性 | Mn /10-6 | Sr /10-6 | K2O /% | Al2O3/% | B /10-6 | Ga /10-6 | La /10-6 | Co /10-6 | K2O /Al2O3 | 校正硼 /10-6 | 相当硼 /10-6 | Sp /‰ | Mn/Sr | B/Ga | h/m | ICV |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
平均值 | 866.34 | 116.68 | 2.23 | 9.81 | 31.07 | 10.64 | 23.52 | 6.71 | 0.23 | 98.16 | 76.00 | 1.43 | 7.66 | 2.44 | 19.74 | 1.20 | |
4 111.49 | 深灰色中砂岩 | 942.40 | 132.00 | 1.66 | 7.90 | 13.37 | 7.25 | 11.78 | 4.85 | 0.21 | 68.46 | 46.86 | 1.35 | 7.14 | 1.84 | 13.23 | 1.09 |
4 111.64 | 深灰色细砂岩 | 872.40 | 108.07 | 1.80 | 8.88 | 16.56 | 8.31 | 15.21 | 5.71 | 0.20 | 78.18 | 54.27 | 1.39 | 8.07 | 1.99 | 15.87 | 1.16 |
4 114.04 | 灰白色含泥砾中砂岩 | 980.00 | 131.46 | 2.03 | 10.07 | 29.05 | 11.00 | 38.25 | 9.57 | 0.20 | 127.26 | 89.59 | 1.56 | 7.45 | 2.64 | 36.50 | 1.52 |
4 114.50 | 灰白色含泥砾中砂岩 | 808.50 | 114.03 | 1.94 | 9.68 | 36.09 | 12.15 | 23.41 | 9.10 | 0.20 | 121.26 | 90.80 | 1.54 | 7.09 | 2.97 | 30.11 | 1.06 |
4 115.44 | 灰白色中砂岩 | 961.60 | 97.58 | 2.53 | 11.99 | 13.41 | 7.32 | 26.29 | 4.04 | 0.21 | 64.77 | 44.78 | 1.33 | 9.85 | 1.83 | 9.04 | 1.08 |
4 116.24 | 灰白色粗砂岩 | 943.10 | 95.79 | 1.76 | 7.91 | 12.62 | 6.13 | 11.47 | 3.16 | 0.22 | 66.65 | 45.40 | 1.34 | 9.85 | 2.06 | 6.06 | 1.15 |
4 116.99 | 灰白色含泥砾中砂岩 | 666.30 | 139.52 | 1.61 | 7.08 | 74.86 | 18.41 | 21.44 | 11.47 | 0.23 | 183.91 | 153.07 | 1.68 | 4.78 | 4.07 | 33.69 | 1.25 |
4 207.82 | 灰白色含砾粗砂岩 | 931.50 | 100.94 | 3.46 | 15.37 | 11.02 | 6.80 | 9.34 | 4.56 | 0.23 | 56.78 | 38.83 | 1.28 | 9.23 | 1.62 | 10.83 | 1.26 |
4 208.57 | 青灰色中砂岩 | 858.60 | 86.53 | 1.65 | 7.00 | 20.80 | 9.54 | 42.17 | 5.56 | 0.24 | 86.24 | 61.39 | 1.43 | 9.92 | 2.18 | 12.43 | 1.13 |
4 209.32 | 青灰色粉砂岩 | 458.20 | 111.11 | 2.05 | 9.18 | 138.66 | 28.25 | 12.92 | 13.67 | 0.22 | 248.13 | 244.30 | 1.78 | 4.12 | 4.90 | 46.07 | 0.86 |
4 209.92 | 灰白色中粗砂岩 | 904.70 | 120.43 | 4.75 | 21.02 | 9.71 | 5.91 | 18.81 | 3.54 | 0.23 | 47.45 | 32.74 | 1.22 | 7.51 | 1.64 | 6.42 | 1.63 |
4 210.32 | 灰白色中粗砂岩 | 899.80 | 90.99 | 1.74 | 6.74 | 10.97 | 5.73 | 48.05 | 3.99 | 0.26 | 59.41 | 40.31 | 1.30 | 9.89 | 1.91 | 9.05 | 1.50 |
4 210.92 | 灰白色粗砂岩 | 971.20 | 114.90 | 1.57 | 6.25 | 20.42 | 9.30 | 11.76 | 6.36 | 0.25 | 82.67 | 59.16 | 1.41 | 8.45 | 2.20 | 18.60 | 1.06 |
4 211.32 | 灰白色中粗砂岩 | 986.10 | 114.38 | 2.10 | 8.92 | 10.48 | 6.14 | 11.00 | 5.06 | 0.24 | 51.20 | 35.33 | 1.25 | 8.62 | 1.71 | 14.33 | 1.47 |
4 211.87 | 灰白色粗砂岩 | 944.20 | 118.42 | 1.74 | 6.80 | 15.01 | 7.61 | 17.01 | 4.12 | 0.26 | 67.51 | 47.28 | 1.34 | 7.97 | 1.97 | 7.84 | 1.25 |
4 212.22 | 灰白色泥砾中砂岩 | 616.60 | 112.31 | 1.89 | 7.67 | 88.68 | 21.87 | 11.97 | 13.91 | 0.25 | 186.11 | 166.69 | 1.69 | 5.49 | 4.06 | 49.28 | 0.90 |
4 212.82 | 青灰色砾质中砂岩 | 764.80 | 117.80 | 4.05 | 16.72 | 34.76 | 14.13 | 14.07 | 6.97 | 0.24 | 100.84 | 78.91 | 1.48 | 6.49 | 2.46 | 15.47 | 0.96 |
4 213.22 | 灰白色含砾粗砂岩 | 973.00 | 205.56 | 2.93 | 12.99 | 11.41 | 5.93 | 47.06 | 3.41 | 0.23 | 57.71 | 39.58 | 1.29 | 4.73 | 1.92 | 6.31 | 1.23 |
4 213.82 | 灰白色含砾粗砂岩 | 1080.80 | 115.86 | 1.68 | 6.74 | 12.74 | 6.88 | 26.29 | 4.20 | 0.25 | 63.68 | 43.76 | 1.32 | 9.33 | 1.85 | 9.13 | 1.38 |
4 214.02 | 青灰色中砂岩 | 762.90 | 105.90 | 1.70 | 7.22 | 40.76 | 14.00 | 10.88 | 10.89 | 0.24 | 144.97 | 106.94 | 1.60 | 7.20 | 2.91 | 44.47 | 0.99 |