0 引言
1 样品及分析条件
1.1 烃源岩样品
1.2 分析测试条件
2 剖面中上奥陶统烃源岩有机质丰度特征
2.1 中上奥陶统萨尔干组(O2+3 s)烃源岩
图2 大湾沟剖面中上奥陶统萨尔干组岩石有机碳、热解数据Fig.2 The TOC and pyrolysis data of source rocks from Middle-Upper Ordovician Salgan Formation in Dawangou outcrop profile |
图3 喀马提坎剖面中上奥陶统萨尔干组岩石有机碳、热解数据Fig.3 The TOC and pyrolysis data of source rocks from Middle-Upper Ordovician Salgan Formation in Kamatikan outcrop profile |
表1 柯坪地区萨尔干组岩石有机质丰度Table 1 The organic matter abundance of source rocks of Salgan Formation from Upper Ordovician in Keping area |
剖面 | 厚度/m | 岩性 | 样品数 | TOC/% | P g/% | T max/℃ | I H/(mg/gTOC) |
---|---|---|---|---|---|---|---|
大湾沟 | 14.6 | 页岩、泥岩 | 28 | (0.04~3.62)/1.83 | (0.02~6.72)/2.94 | (444~518)/460 | (1~181)/116 |
灰岩、泥灰岩 | 13 | (0.01~1.20)/0.15 | (0.03~2.74)/0.33 | (384~515)/461 | (63~221)/118 | ||
喀马提坎 | 15.6 | 页岩、泥岩 | 15 | (0.19~3.43)/1.40 | (0.08~2.28)/0.66 | (442~476)/454 | (16~62)/37 |
灰岩、泥灰岩 | 5 | (0.01~0.48)/0.15 | (0.03~0.28)/0.10 | (439~469)/453 | (41~154)/91 | ||
通古斯布隆 | 10.6 | 页岩、泥岩 | 11 | (0.69~2.85)/1.66 | (0.23~1.08)/0.64 | (438~445)/441 | (11~59)/39 |
灰岩 | 10 | (0.01~0.05)/0.02 | (0.01~0.04)/0.02 | (449~475)/463 | (32~156)/81 | ||
阿恰西一沟 | 7.5 | 灰岩 | 16 | (0.01~0.02)/0.02 | (0.00~0.03)/0.02 | (445~500)/465 | (0~322)/83 |
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2.2 上奥陶统印干组(O3 y)烃源岩
图4 大湾沟剖面上奥陶统印干组岩石有机碳、热解数据Fig.4 The TOC and pyrolysis data of source rocks from Upper Ordovician Yingan Formation in Dawangou outcrop profile |
表2 柯坪地区上奥陶统印干组烃源岩有机质丰度Table 2 The organic matter abundance of source rocks of Yingan Formation from Upper Ordovician in Keping area |
剖面 | 厚度/m | 岩性 | 样品数 | TOC/% | P g/% | T max/℃ | I H/(mg/gTOC) |
---|---|---|---|---|---|---|---|
大湾沟 | 29 | 页岩、泥岩 | 16 | (0.44~1.29)/0.67 | (0.41~1.54)/1.02 | (443~455)/450 | (50~133)/93 |
灰岩、泥灰岩 | 9 | (0.14~0.54)/0.31 | (0.03~0.91)/0.37 | (339~455)/438 | (10~100)/60 | ||
羊吉坎 (阿恰西二沟) | 169 | 页岩、泥岩 | 13 | (0.07~0.34)/0.22 | (0.03~0.15)/0.09 | (465~500)/489 | (15~41)/28 |
灰岩、泥灰岩 | 12 | (0.02~0.24)/0.12 | (0.01~0.10)/0.04 | (434~504)/479 | (8~56)/28 | ||
阿恰西五沟 | 14.7 | 页岩、泥岩 | 19 | (0.14~0.38)/0.27 | (0.02~0.06)/0.04 | (480~544)/503 | (9~20)/13 |
灰岩 | 3 | (0.05~0.09)/0.06 | (0.02~0.07)/0.05 | (489~513)/503 | (22~99)/66 |
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3 烃源岩分子标志物特征
3.1 正构烷烃分布特征
3.2 姥姣烷/植烷(Pr/Ph)值
3.3 三环萜烷和藿烷系列
3.4 甾烷系列
3.5 二苯并噻吩/菲(DBT/P)
图10 柯坪地区露头剖面寒武系—奥陶系烃源岩二苯并噻吩/菲比值(DBT/P)—姥姣烷/植烷值(Pr/Ph)关系(图版据文献[30])图中:Zone 1A:海相碳酸盐岩区;Zone 1B:海相碳酸盐岩、灰泥岩、富硫湖湘;Zone 2:湖相超盐环境;Zone 3:海相页岩和其他湖相;Zone 4:河流/三角洲相页岩和煤 Fig.10 Plot of DBT/P versus Pr/Ph value in Cambrian to Ordovician source rocks from outcrops profiles in Keping area (plate according to Ref.[30]) |