山东黄县早第三纪断陷盆地低水位和扩张体系域聚煤作用分析
- 1. 山东矿业学院;
- 2. 中国科学院地质研究所
基金项目:
山东省自然科学基金,煤炭科学基金
作者简介:
李增学,男,1954年出生,教授,博士,层序地层学,煤田地质学
- 收稿日期:
1998-01-08
- 刊出日期:
1999-06-10
摘要: 山东黄县早第三纪断陷盆地充填沉积序列可以划分出三个构造—沉积旋回,而盆地断裂活动是控制盆地充填沉积的主导因素。根据构造—沉积旋回、层序界面和盆地演化特点分析,下第三系共划分出三个层序,层序Ⅱ和层序Ⅲ含煤和含油。低水位体系域和扩张体系域都有聚煤作用发生,而前者最强。聚煤作用中心随盆地沉积层序的不同演化阶段发生迁移,低水位期主要位于盆缘至盆地中心的过渡带,盆地中心也有聚煤作用发生:扩张期聚煤作用中心向盆缘区迁移,且范围缩小:萎缩期聚煤作用最弱,一般在盆地中心区,且分布范围局限。在黄县断陷盆地充填层序中,油页岩可以作为层序中的密集段。
Coal Accumulation in the Lowstand and Highstand Systems T racts in the Huangxian Paleogene Faulted Basin
- 1. Shandong Institute of Mining & Tech,Tai'an Shangdong 271019;
- 2. Institute of Geology,Chinese Academy of Science,Beijing 100029
- Received Date:
1998-01-08
- Publish Date:
1999-06-10
Abstract: The Huangxian Paleogene faulted basin is located at the northwestern marg in o f the Jiaobei faulted uplift,the Eastern Shandong faulted block,east to the Tanl u Fracture zone.It is a terrestrial depositional basin,belong to the coal,oil an d gas faulted basin in uplifted block.Two kinds of sequence boundaries are recog nized in the basin filling succession.One is regional tectonic boundary,displayi ng as the regional unconformity.The other is the tectonic-depositional mechanics -transforming boundary,that is the basin water expand or shrink due to the basin tectonics transformation (tectonic stress field change).The upper part of the te ctonic-depositional mechanics boundary is different from the lower part in depos itional association. Three tectonic-depositional cycles can be distinguished in the basin filling suc cession,which were controlled by the activity of the marginal faults of the basi n,According to the tectonic-depositional cycles,the sequences boundaries and the analysis to the evolution of the basin,three sequences can be divided,that is, sequence Ⅰ,Ⅱ and Ⅲ from bottom to top.The sequence Ⅱ and Ⅲ are complete th ird-order sequences,with lowstand,transgressive and highstand systems tracts,con taining coal,oil and gas deposits,Five genetic stratigraphic units can be identi fied.The sequence Ⅰ is mainly fluvial depositional system,forming the first gen etic stratigraphic unit,The lowstand and transgressive systems tracts in sequenc e Ⅱ and Ⅲ constitute four genetic units respectively.The evolution of the faul ted basin was controlled by the tectonic activity in the basin.The lake level ch anges were expressed as integral water expansion or shrink,not in a single direc tion. Study shows that the coal accumulation occurred in both the lowstand and transgr essive systems tracts,stronger in the lowstand systems tracts.The centers of the coal accumulation migrated with the evolution of the sequences.The coal accumul a ted mainly in the transitional belt from the basin's center to margin,also in th e center of the basin.The coal accumulation centers migrated toward the basin's margin in the transgressive systems tracts,with smaller scopes.There was only sm all-scaled coal accumulation in the highstand systems tracts,occurring in the ce nter part of the basin. The activity of the basin's marginal faults was relative ly stable in the lowstand periods.In despite of fluvial-braided river system dev el oped in the basin.the blocks outside the basin uplifted in a small scale.The coa rse sediment supply was not abundant.The lake basin with shallow water beneaped and gradually became swamp,further transmulated to peat swamp,forming large-scal ed coalbeds. The oil shales and the oil-bearing shales in the basin's filling succession cont ain a lot of animal remains and animal fragments distributed in the top of the l owstand systems tracts,which,the authors believe,may be the condensed interval i n the basin's sequence.They are important ore-bearing layers,playing key roles i n the sequence division.
李增学, 魏久传, 兰恒星, 李守春. 山东黄县早第三纪断陷盆地低水位和扩张体系域聚煤作用分析[J]. 沉积学报, 1999, 17(2): 247-251.
引用本文: |
李增学, 魏久传, 兰恒星, 李守春. 山东黄县早第三纪断陷盆地低水位和扩张体系域聚煤作用分析[J]. 沉积学报, 1999, 17(2): 247-251.
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LI Zeng xue, WEI Jiu chuan, LAN Heng xing, LI Shou chun. Coal Accumulation in the Lowstand and Highstand Systems T racts in the Huangxian Paleogene Faulted Basin[J]. Acta Sedimentologica Sinica, 1999, 17(2): 247-251.
Citation: |
LI Zeng xue, WEI Jiu chuan, LAN Heng xing, LI Shou chun. Coal Accumulation in the Lowstand and Highstand Systems T racts in the Huangxian Paleogene Faulted Basin[J]. Acta Sedimentologica Sinica, 1999, 17(2): 247-251.
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