塔里木盆地塔中地区志留系测井层序地层学研究
- 石油大学,北京 100083
作者简介:
陈方鸿,男,29岁,助教,沉积学。
- 收稿日期:
1997-12-20
- 修回日期:
1998-03-14
- 刊出日期:
1999-03-10
摘要: 在岩心刻度测井资料的基础上,综合应用常规测井、能谱测井、倾角测井和成象测井资料,建立塔中地区志留系沉积微相测井解释模型。塔中地区志留系以碎屑潮坪沉积为主,可分为潮下砂坪、潮道、潮间混合坪、潮上泥坪微相。志留系中可识别出4个测井层序边界,划分为3个测井层序,每个层序由海侵体系域和高水位体系域组成。测井层序对比和古水流统计分析表明,志留纪海水自NW向SE侵入,具有双向水流特征。沉积相的叠置和横向分布受海平面相对变化速率和可容空间的控制。
On Logging-sequence Stratigraphy of Silurian in Tazhong Area, Tarim Basin
- University of Petroleum,Beijing 102200
- Received Date:
1997-12-20
- Rev Recd Date:
1998-03-14
- Publish Date:
1999-03-10
Abstract: On the basis of core scaling logging data, the logging data interpretation model of Silurian sedimentary micro facies in Tazhong area is established by comprehensive application of conventional logging,natural gamma ray spectrometry(NGS),diplog and image log data.The Silurian in the study area consist of detritus tidal flat deposits,which is divided into subtidal sand flat, tidal channel,intertidal mixed flat and supratidal mudflat.Four logging-sequence boundaries are recongnized.The top and bottom of the Silurian belong to type-I sequence boundary,and its interior belong to type-Ⅱ sequence boundary. Characteristics of these sequence boundaries are described as follows: 1) the pattern in conventional logging and NGS curves is step- sudden change contact, 2) obvious difference either size or direction of dip vectors in the result map of stratum dip vector,3) both stratigraphic attitude and contact relation are also obviously different in FMI images. The Silurian is divided into 3 logging -sequences.which are named as sequenceⅠ,Ⅱ and Ⅲ from the bottom to the top and each one is composed of transgressive system tract(TST)and high stand system tract(HST).TST is mainly sand flat and mixed flat deposits, whose parasequence superimposed pattern shows that the grain size and ratio of sand to mud increase in the vertical, and retrograding bell-shaped series in GR and SP curves.HST is composed of mixed flat and mudflat, whose parasequence superimposed pattern shows that mudrock increases.sand decreases,and ratio of sand to mud decreases in the vertical, which forms accretionary parasequence group,and the straight-ling or box appear in GR and SP curves.By comprehensive analysis of sequence stratigraphy, it is shown that different eustatic rate of relative sea-level result in regular change of accommodation and superimposition in the vertical of microfacies in the transversal of each sequence.By palaeocurrent statistics and analysis from sequence Ⅰ to Ⅲ, it can be seen that current direction in Silurian of this area is double, which is mainly NE-SE.The above analysis shows that logging data is important for the study of sequence stratigraphy,especially for determining stratigraphic series, recognizing sequence boundary,dividing sequence and system tracts and determining palaeocurrent direction.The method is intuitive and clear.
陈方鸿, 王贵文. 塔里木盆地塔中地区志留系测井层序地层学研究[J]. 沉积学报, 1999, 17(1): 58-62.
引用本文: |
陈方鸿, 王贵文. 塔里木盆地塔中地区志留系测井层序地层学研究[J]. 沉积学报, 1999, 17(1): 58-62.
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Chen Fanghong, Wang Guiwen. On Logging-sequence Stratigraphy of Silurian in Tazhong Area, Tarim Basin[J]. Acta Sedimentologica Sinica, 1999, 17(1): 58-62.
Citation: |
Chen Fanghong, Wang Guiwen. On Logging-sequence Stratigraphy of Silurian in Tazhong Area, Tarim Basin[J]. Acta Sedimentologica Sinica, 1999, 17(1): 58-62.
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