Sedimentary process research is of great significance for understanding the distribution and characteristics of sediments.Through the detailed observation and measurement of the Sangyuan outcrop in Luanping Basin,this...Sedimentary process research is of great significance for understanding the distribution and characteristics of sediments.Through the detailed observation and measurement of the Sangyuan outcrop in Luanping Basin,this paper studies the depositional process of the hyperpycnal flow deposits,and divides their depositional process into three phases,namely,acceleration,erosion and deceleration.In the acceleration phase,hyperpycnal flow begins to enter the basin nearby,and then speeds up gradually.Deposits developed in the acceleration phase are reverse.In addition,the original deposits become unstable and are taken away by hyperpycnal flows under the eroding force.As a result,there are a lot of mixture of red mud pebbles outside the basin and gray mud pebbles within the basin.In the erosion phase,the reverse deposits are eroded and become thinner or even disappear.Therefore,no reverse grading characteristic is found in the proximal major channel that is closer to the source,but it is still preserved in the middle branch channel that is far from the source.After entering the deceleration phase,normally grading deposits appear and cover previous deposits.The final deposits in the basin are special.Some are reverse,and others are normal.They are superimposed with each other under the action of hyperpycnal flow.The analysis of the Sangyuan outcrop demonstrates the sedimentary process and distribution of hyperpycnites,and reasonably explain the sedimentary characteristics of hyperpycnites.It is helpful to the prediction of oil and gas exploration targets in gravity flow deposits.展开更多
We thank Tan Mingxuan et al. （2017） for their comments stimulated by our short paper in the recent Acta Geologica Sinica （English edition）. We are grateful for the opportunity to expand on the model of the supercr...We thank Tan Mingxuan et al. （2017） for their comments stimulated by our short paper in the recent Acta Geologica Sinica （English edition）. We are grateful for the opportunity to expand on the model of the supercritical hyperpycnal flow deposits in the Beilaishi section on the Lingshan Island, and to explain why the model proposed by Tan Mingxuan et al. （2017） cannot explain the bulk of the deposits in the Beilaishi section. We do not dispute that the recognition of supercritical flow deposits remains ambiguous （Ono and Plink-Bjorklund, 2017）. To some extent, the morphology of deep-water supercritical flow deposits is similar to hummocky and swaley cross- stratification （Ono and Plink-Bjorklund, 2017）. Besides, distinguishing the deposits laid down by gravity flows in deep-water systems from those produced by storm-related combined flows in continental shelf systems is not an easy task （Ono and Plink-Bjorklund, 2017）. However, a correct interpretation is crucial for understanding the paleogeographic and depositional model.展开更多
Objective Understanding the dynamics of sediment gravity flows is of great importance to correctly interpret their related deposits. The discovery of supercritical sediment gravity flows provides some new viewpoints ...Objective Understanding the dynamics of sediment gravity flows is of great importance to correctly interpret their related deposits. The discovery of supercritical sediment gravity flows provides some new viewpoints for the explanation of controversial sediment gravity flow deposits. However, the dynamics, formation, evolution processes of supercritical sediment gravity flows and their recognition criteria from their associated deposits are still worldwide controversial. The supercritical hyperpycnal flow deposits recognized in the upper part of Early Cretaceous Lingshandao Formation provide a rare opporttmity to understand their sedimentary characteristics. This work is aimed at documenting the typical sedimentary structures associated with the supercritical hyperpycnal flow, and discussing the vertical stacking and its relationship with flow evolution.展开更多
Based on core,logging,lab test and seismic data,sedimentary characteristics and pattern of marine hyperpycnal flow,the distribution rules of hyperpycnal flow reservoir,prediction method of favorable hyperpycnal flow r...Based on core,logging,lab test and seismic data,sedimentary characteristics and pattern of marine hyperpycnal flow,the distribution rules of hyperpycnal flow reservoir,prediction method of favorable hyperpycnal flow reservoir zones,hydrocarbon accumulation model in hyperpycnal flow reservoir in D block of Bay of Bengal were investigated,and the favorable exploration zone and well sites were predicted.Pliocene in D block has typical hyperpycnal flow sediment,which is a set of fine-medium sandstone held between thick layers of marine mudstone and features a series of reverse grading unit and normal grading unit pairs.The hyperpycnal flow sediment appears as heavily jagged box shape,bell shape and tongue shape facies on log curves with linear gradient,and corresponds to multiple phases of deep channels on the seismic section and high sinuous channel on stratal slices.The sedimentary bodies formed by a single phase hyperpycnal flow which include five types of microfacies,namely,supply channel(valley),channel complex,branch channel,levee and sheet sand.The hyperpycnal flow sediments appear in multiple branches,multiple generations and stages in space,forming high-quality reservoirs in strips on the plane and superposition vertically,with fairly good physical properties.The channel complex sandstone,with large thickness,coarse particle size and good physical properties,is the most favorable exploration facies.Based on the guidance of the sedimentary model,distribution of the channel complex microfacies was delineated in detail by seismic reflection structure analysis,spectrum waveform characteristic analysis,slice and attribute fusion,and combined with the structural feature analysis,the favorable drilling zone was sorted out,effectively guiding the exploration deployment of the block.展开更多
基金the Scientific research and technology development project of Petro China(2021DJ5303)。
文摘Sedimentary process research is of great significance for understanding the distribution and characteristics of sediments.Through the detailed observation and measurement of the Sangyuan outcrop in Luanping Basin,this paper studies the depositional process of the hyperpycnal flow deposits,and divides their depositional process into three phases,namely,acceleration,erosion and deceleration.In the acceleration phase,hyperpycnal flow begins to enter the basin nearby,and then speeds up gradually.Deposits developed in the acceleration phase are reverse.In addition,the original deposits become unstable and are taken away by hyperpycnal flows under the eroding force.As a result,there are a lot of mixture of red mud pebbles outside the basin and gray mud pebbles within the basin.In the erosion phase,the reverse deposits are eroded and become thinner or even disappear.Therefore,no reverse grading characteristic is found in the proximal major channel that is closer to the source,but it is still preserved in the middle branch channel that is far from the source.After entering the deceleration phase,normally grading deposits appear and cover previous deposits.The final deposits in the basin are special.Some are reverse,and others are normal.They are superimposed with each other under the action of hyperpycnal flow.The analysis of the Sangyuan outcrop demonstrates the sedimentary process and distribution of hyperpycnites,and reasonably explain the sedimentary characteristics of hyperpycnites.It is helpful to the prediction of oil and gas exploration targets in gravity flow deposits.
文摘We thank Tan Mingxuan et al. （2017） for their comments stimulated by our short paper in the recent Acta Geologica Sinica （English edition）. We are grateful for the opportunity to expand on the model of the supercritical hyperpycnal flow deposits in the Beilaishi section on the Lingshan Island, and to explain why the model proposed by Tan Mingxuan et al. （2017） cannot explain the bulk of the deposits in the Beilaishi section. We do not dispute that the recognition of supercritical flow deposits remains ambiguous （Ono and Plink-Bjorklund, 2017）. To some extent, the morphology of deep-water supercritical flow deposits is similar to hummocky and swaley cross- stratification （Ono and Plink-Bjorklund, 2017）. Besides, distinguishing the deposits laid down by gravity flows in deep-water systems from those produced by storm-related combined flows in continental shelf systems is not an easy task （Ono and Plink-Bjorklund, 2017）. However, a correct interpretation is crucial for understanding the paleogeographic and depositional model.
基金the National Science Foundation of China (grant No.U1262203)the National Science and Technology Special Grant (grant No.2016ZX05006-007) for their financial support
文摘Objective Understanding the dynamics of sediment gravity flows is of great importance to correctly interpret their related deposits. The discovery of supercritical sediment gravity flows provides some new viewpoints for the explanation of controversial sediment gravity flow deposits. However, the dynamics, formation, evolution processes of supercritical sediment gravity flows and their recognition criteria from their associated deposits are still worldwide controversial. The supercritical hyperpycnal flow deposits recognized in the upper part of Early Cretaceous Lingshandao Formation provide a rare opporttmity to understand their sedimentary characteristics. This work is aimed at documenting the typical sedimentary structures associated with the supercritical hyperpycnal flow, and discussing the vertical stacking and its relationship with flow evolution.
基金Supported by the CNPC Overseas Science and Technology Project(CNODC/CAL/KJZX/2015-016)
文摘Based on core,logging,lab test and seismic data,sedimentary characteristics and pattern of marine hyperpycnal flow,the distribution rules of hyperpycnal flow reservoir,prediction method of favorable hyperpycnal flow reservoir zones,hydrocarbon accumulation model in hyperpycnal flow reservoir in D block of Bay of Bengal were investigated,and the favorable exploration zone and well sites were predicted.Pliocene in D block has typical hyperpycnal flow sediment,which is a set of fine-medium sandstone held between thick layers of marine mudstone and features a series of reverse grading unit and normal grading unit pairs.The hyperpycnal flow sediment appears as heavily jagged box shape,bell shape and tongue shape facies on log curves with linear gradient,and corresponds to multiple phases of deep channels on the seismic section and high sinuous channel on stratal slices.The sedimentary bodies formed by a single phase hyperpycnal flow which include five types of microfacies,namely,supply channel(valley),channel complex,branch channel,levee and sheet sand.The hyperpycnal flow sediments appear in multiple branches,multiple generations and stages in space,forming high-quality reservoirs in strips on the plane and superposition vertically,with fairly good physical properties.The channel complex sandstone,with large thickness,coarse particle size and good physical properties,is the most favorable exploration facies.Based on the guidance of the sedimentary model,distribution of the channel complex microfacies was delineated in detail by seismic reflection structure analysis,spectrum waveform characteristic analysis,slice and attribute fusion,and combined with the structural feature analysis,the favorable drilling zone was sorted out,effectively guiding the exploration deployment of the block.
