Pub Date : 2019-05-28DOI: 10.5772/INTECHOPEN.85517
P. S. Momta
Sedimentary facies and structural lineaments represent significant control factors on hydrocarbon flow behavior. These geological elements have been evaluated to understand possible cause(s) of rapid decline in pro¬duction. The N5.2 reservoir, located in shallow marine sandstones, offshore Niger Delta, has experienced decline in oil rate with a corresponding increase in water-cut within two years of beginning of production. The main objective of this study is the determination of reservoir architecture in order to individuate the possible cause(s) of rapid production decline. To this aim, several methods have been used, including the seismic attribute analysis, electrofacies analysis, well log and petrophysical correlations. The obtained results show that the N5.2 reservoir is a massive sandy unit, occur-ring within the paralic Agbada Formation of about 2133 m thick. A contour depth map of the reservoir shows the occurrence of a structural saddle associated with an elongated closure having two structural culminations. Further analysis using the root mean square (RMS) and anti-tracking seismic attributes has indicated a seismic facies parallel to the paleo-coastline direction and several faults and fractures. The high quality of the reservoir, fractures, poor management and water injection may have induced rapid fluid flow and consequently early watercut and decline in production.
{"title":"Geologic Characteristics and Production Response of the N5.2 Reservoir, Shallow Offshore Niger Delta, Nigeria","authors":"P. S. Momta","doi":"10.5772/INTECHOPEN.85517","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.85517","url":null,"abstract":"Sedimentary facies and structural lineaments represent significant control factors on hydrocarbon flow behavior. These geological elements have been evaluated to understand possible cause(s) of rapid decline in pro¬duction. The N5.2 reservoir, located in shallow marine sandstones, offshore Niger Delta, has experienced decline in oil rate with a corresponding increase in water-cut within two years of beginning of production. The main objective of this study is the determination of reservoir architecture in order to individuate the possible cause(s) of rapid production decline. To this aim, several methods have been used, including the seismic attribute analysis, electrofacies analysis, well log and petrophysical correlations. The obtained results show that the N5.2 reservoir is a massive sandy unit, occur-ring within the paralic Agbada Formation of about 2133 m thick. A contour depth map of the reservoir shows the occurrence of a structural saddle associated with an elongated closure having two structural culminations. Further analysis using the root mean square (RMS) and anti-tracking seismic attributes has indicated a seismic facies parallel to the paleo-coastline direction and several faults and fractures. The high quality of the reservoir, fractures, poor management and water injection may have induced rapid fluid flow and consequently early watercut and decline in production.","PeriodicalId":178387,"journal":{"name":"Sedimentation Engineering [Working Title]","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122271628","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-05-23DOI: 10.5772/INTECHOPEN.85591
P. Chaudhuri, S. Chaudhuri, R. Ghosh
Mangroves provide a distinctive mechanism of trapping sediment and accelerat-ing land-building processes in tide-dominated coastal and estuarine environments. The complex hydrodynamic and salinity conditions, accumulation rates of both organic and inorganic sediments, primary surface elevation, and hydroperiod influence sediment retention mechanism within mangrove ecosystems. Abundant terrigenous sediment supply can form dynamic mud banks and the complex aerial root system of mangroves may lead to accretion of sediment by weakening the tidal velocity. Such mechanisms are often enhanced by organic flocculation. The efficiency of sediment trapping by mangroves is species specific. Adaptability and resilience of mangroves enable them to cope with the moderate to high rates of sea level rise. However, subsurface movements and deep subsidence due to autocompaction may augment the effects of relative sea level rise. Increasing population pressure and forest-based economic activities have caused global reduction of mangrove coverage challenging the sedimentation processes. Marker horizon techniques and surface elevation table (SET) tests have facilitated assessment of spatial variability in patterns of sediment accretion and surface elevation in various coastal sites of species-diverse Southeast Asia, especially coastal Malaysia and Thailand. The mangroves of the eastern coast of India have witnessed sediment retention, having an association with the seasonal rainfall regime.
{"title":"The Role of Mangroves in Coastal and Estuarine Sedimentary Accretion in Southeast Asia","authors":"P. Chaudhuri, S. Chaudhuri, R. Ghosh","doi":"10.5772/INTECHOPEN.85591","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.85591","url":null,"abstract":"Mangroves provide a distinctive mechanism of trapping sediment and accelerat-ing land-building processes in tide-dominated coastal and estuarine environments. The complex hydrodynamic and salinity conditions, accumulation rates of both organic and inorganic sediments, primary surface elevation, and hydroperiod influence sediment retention mechanism within mangrove ecosystems. Abundant terrigenous sediment supply can form dynamic mud banks and the complex aerial root system of mangroves may lead to accretion of sediment by weakening the tidal velocity. Such mechanisms are often enhanced by organic flocculation. The efficiency of sediment trapping by mangroves is species specific. Adaptability and resilience of mangroves enable them to cope with the moderate to high rates of sea level rise. However, subsurface movements and deep subsidence due to autocompaction may augment the effects of relative sea level rise. Increasing population pressure and forest-based economic activities have caused global reduction of mangrove coverage challenging the sedimentation processes. Marker horizon techniques and surface elevation table (SET) tests have facilitated assessment of spatial variability in patterns of sediment accretion and surface elevation in various coastal sites of species-diverse Southeast Asia, especially coastal Malaysia and Thailand. The mangroves of the eastern coast of India have witnessed sediment retention, having an association with the seasonal rainfall regime.","PeriodicalId":178387,"journal":{"name":"Sedimentation Engineering [Working Title]","volume":" 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131977424","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-04-04DOI: 10.5772/INTECHOPEN.85589
Özlem Bulkan, Bilgehan Toksoy Ediş, M. N. Çağatay
A hypothetical novel, which aims to summarize the whole geological history of the coastal area surrounding the Mediterranean Sea, probably contains a sum of intensive and impressive topics, such as tsunamis, storms, earthquakes, volcanic activities, human-nature interactions, and their products. These abrupt geo-event changes (e.g., water chemistry fluctuations) remark a dynamic nature of this unique coastal area. Paleolimnological studies of a coastal lacustrine archive (i.e., Lake Bafa, Turkey), associated with syngenetic deposits accumulated in neighboring geological settings (i.e., swamp, deltaic, lagoon, marine), has allowed us to reconstruct the local geological history. Following this hypothesis, we aimed at investigating the paleoenvironmental establishment of the Lake Bafa and surrounding coastal area. Lithologic and geochemical investigations of the lacustrine ( “ BAF37:4.2 m) core and surrounding swamp ( “ BS ” :12 m) sediments supplied us an excellent geo-archive, continuously accumulated during the last 4.5 ky. Following conclusions are provided concerning the main depositional stages: Recent swamp-lacustrine separated stage (S-I: last 0.8 ky), lagoon stage (S-II.: 0.8 – 1.75 ky BP), marine-river interaction stage (S-III: 1.75 – 2.7 ky BP), and marine-dominated stage (S-IV: 2.7 – 4.5 ky BP). Our observations indicate that ecosystem characteristics of the basin have been mainly controlled by the hydroclimate and geotectonic processes.
一本假想的小说，旨在总结地中海沿岸地区的整个地质历史，可能包含一系列密集而令人印象深刻的主题，如海啸、风暴、地震、火山活动、人与自然的相互作用及其产物。这些突发性地质事件变化(例如，水化学波动)反映了这一独特沿海地区的动态性质。对沿海湖泊档案(即土耳其巴法湖)的古湖泊学研究，结合在邻近地质环境(即沼泽、三角洲、泻湖、海洋)中积累的同生沉积物，使我们能够重建当地的地质历史。在此基础上，对八发湖及周边沿海地区的古环境建设进行了研究。湖泊(BAF37:4.2 m)岩心和周围沼泽(BS:12 m)沉积物的岩性和地球化学调查为我们提供了一个优秀的地质档案，在过去的4.5 ky中不断积累。主要沉积阶段有:最近的沼泽-湖泊分离阶段(S-I:最后0.8 ky)，泻湖阶段(S-II)。: 0.8 - 1.75 ky BP)、海洋-河流相互作用阶段(S-III: 1.75 - 2.7 ky BP)和海洋主导阶段(S-IV: 2.7 - 4.5 ky BP)。研究表明，盆地的生态系统特征主要受水文气候和大地构造过程的控制。
{"title":"“Geo-archives of a Coastal Lacustrine Eco-system”: Lake Bafa (Mediterranean Sea)","authors":"Özlem Bulkan, Bilgehan Toksoy Ediş, M. N. Çağatay","doi":"10.5772/INTECHOPEN.85589","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.85589","url":null,"abstract":"A hypothetical novel, which aims to summarize the whole geological history of the coastal area surrounding the Mediterranean Sea, probably contains a sum of intensive and impressive topics, such as tsunamis, storms, earthquakes, volcanic activities, human-nature interactions, and their products. These abrupt geo-event changes (e.g., water chemistry fluctuations) remark a dynamic nature of this unique coastal area. Paleolimnological studies of a coastal lacustrine archive (i.e., Lake Bafa, Turkey), associated with syngenetic deposits accumulated in neighboring geological settings (i.e., swamp, deltaic, lagoon, marine), has allowed us to reconstruct the local geological history. Following this hypothesis, we aimed at investigating the paleoenvironmental establishment of the Lake Bafa and surrounding coastal area. Lithologic and geochemical investigations of the lacustrine ( “ BAF37:4.2 m) core and surrounding swamp ( “ BS ” :12 m) sediments supplied us an excellent geo-archive, continuously accumulated during the last 4.5 ky. Following conclusions are provided concerning the main depositional stages: Recent swamp-lacustrine separated stage (S-I: last 0.8 ky), lagoon stage (S-II.: 0.8 – 1.75 ky BP), marine-river interaction stage (S-III: 1.75 – 2.7 ky BP), and marine-dominated stage (S-IV: 2.7 – 4.5 ky BP). Our observations indicate that ecosystem characteristics of the basin have been mainly controlled by the hydroclimate and geotectonic processes.","PeriodicalId":178387,"journal":{"name":"Sedimentation Engineering [Working Title]","volume":"103 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114274094","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-03-18DOI: 10.5772/INTECHOPEN.85207
T. Uda, Shiho Miyahara, T. San-nami, M. Serizawa
The long-term beach changes along the Kaike coast (Japan) have been investigated. Being a major source of sand to this coast, the Hino River has supplied a large amount of sand during the extensive mining of iron sand in the past, resulting in the shoreline advance. However, the stoppage of the sand mining has caused a marked decrease in the sand supply, resulting in a rapid shoreline recession around the river delta. The beach changes triggered by these human activities have been investigated using an old geographical map and aerial photographs taken between 1947 and 2005. Then, the beach changes have been reproduced using the contour-line-change model considering the change in grain size of the beach sediments. Bathymetric data have been analyzed in order to evaluate the longshore sand transport and the fluvial sand supply from the Hino River. The measured and predicted three-dimensional beach changes were in good agreement and the effec-tiveness of the contour-line-change model for predicting long-term beach changes was confirmed by this case history.
{"title":"A Long-Term Prediction of Beach Changes around River Delta using Contour-Line-Change Model","authors":"T. Uda, Shiho Miyahara, T. San-nami, M. Serizawa","doi":"10.5772/INTECHOPEN.85207","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.85207","url":null,"abstract":"The long-term beach changes along the Kaike coast (Japan) have been investigated. Being a major source of sand to this coast, the Hino River has supplied a large amount of sand during the extensive mining of iron sand in the past, resulting in the shoreline advance. However, the stoppage of the sand mining has caused a marked decrease in the sand supply, resulting in a rapid shoreline recession around the river delta. The beach changes triggered by these human activities have been investigated using an old geographical map and aerial photographs taken between 1947 and 2005. Then, the beach changes have been reproduced using the contour-line-change model considering the change in grain size of the beach sediments. Bathymetric data have been analyzed in order to evaluate the longshore sand transport and the fluvial sand supply from the Hino River. The measured and predicted three-dimensional beach changes were in good agreement and the effec-tiveness of the contour-line-change model for predicting long-term beach changes was confirmed by this case history.","PeriodicalId":178387,"journal":{"name":"Sedimentation Engineering [Working Title]","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124105102","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-03-13DOI: 10.5772/INTECHOPEN.85208
Z. Shi, Dong-chun Yan, A. Wen, Yong-yan Wang
The riparian zone of the Three Gorges Reservoir serves as a critical transitional zone located between the aquatic and surrounding terrestrial environments. The periodic anti-seasonal alternation of wet and dry periods results in an intensive exchange of substance within the riparian zone. The discrimination of the sources of the sediments deposited within the riparian zone is of fundamental importance for the evaluation of the soil pollution and associated environmental impacts and for the protection of the water quality in the reservoir. In this study, a composite fingerprinting technique has been applied to apportion the sediment sources for the riparian zone with different elevations, ranging between 145—155, 155–165, and 165–175 m in a typical tributary channel. From a sediment perspective, the sediments suspended from the Yangtze mainstream represent the primary sources of the riparian deposits. From a contamination perspective, the sediment input from the Ruxi tributary channel represents an important source of pollution for the riparian environment. More effective sediment and sediment-associated contaminant control plans are needed to reduce the potential environmental problems of the riparian zone.
{"title":"Fingerprinting Sources of the Sediments Deposited in the Riparian Zone of the Ruxi Tributary Channel of the Three Gorges Reservoir (China)","authors":"Z. Shi, Dong-chun Yan, A. Wen, Yong-yan Wang","doi":"10.5772/INTECHOPEN.85208","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.85208","url":null,"abstract":"The riparian zone of the Three Gorges Reservoir serves as a critical transitional zone located between the aquatic and surrounding terrestrial environments. The periodic anti-seasonal alternation of wet and dry periods results in an intensive exchange of substance within the riparian zone. The discrimination of the sources of the sediments deposited within the riparian zone is of fundamental importance for the evaluation of the soil pollution and associated environmental impacts and for the protection of the water quality in the reservoir. In this study, a composite fingerprinting technique has been applied to apportion the sediment sources for the riparian zone with different elevations, ranging between 145—155, 155–165, and 165–175 m in a typical tributary channel. From a sediment perspective, the sediments suspended from the Yangtze mainstream represent the primary sources of the riparian deposits. From a contamination perspective, the sediment input from the Ruxi tributary channel represents an important source of pollution for the riparian environment. More effective sediment and sediment-associated contaminant control plans are needed to reduce the potential environmental problems of the riparian zone.","PeriodicalId":178387,"journal":{"name":"Sedimentation Engineering [Working Title]","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114367897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：