Interpretation-A Journal of Subsurface Characterization最新文献

{"title":"Characteristics and controlling factors of petroliferous reservoirs in the Permian Lower Urho Formation, western Mahu Slope, Junggar Basin, NW China","authors":"Zhiyuan Fang, Weiguo Hao, Maidina Nuertai, F. Zhang, Beibei Mao, Naixiang He","doi":"10.1190/int-2022-0122.1","DOIUrl":"https://doi.org/10.1190/int-2022-0122.1","url":null,"abstract":"Numerous hydrocarbon discoveries in the Lower Urho Formation of the western Mahu Slope, China indicate that potential petroliferous reservoirs may exist in that region. However, issues concerning the reservoir characteristics and associated controlling factors remain unclear. To determine the characteristics and associated controlling factors of those reservoirs, an integrated analysis of three-dimensional seismic volume, wireline logs, mud logs, cores, thin sections, porosity, and permeability data was conducted. Several lithological types were identified from the core, casting thin section, and mud log data (including mudstone, sandstone, gravity flow-derived glutenite, transitional glutenite, and traction flow-derived glutenite). The contact relationship was determined from the casting thin section data, and it included point contact and lineal contact, followed by concavo-convex contact and suture contact. The dominant pore types were found to be intergranular pores, followed by intragranular pores, intramatrix pores, and cracks. The porosity and permeability data reveal that sandstone and traction flow-derived glutenite commonly form low-porosity and low-permeability reservoir, whereas transitional glutenite commonly forms low-porosity and ultralow-permeability reservoirs and gravity flow-derived glutenite generally forms low-porosity and ultralow-permeability reservoirs. This integrated analysis shows that tectonic movements and sedimentary environment control the physical properties of the reservoirs. The tectonic movements control reservoir characteristics through thrust fault systems and the large-scale provenance, and the sedimentary environment controls reservoir characteristics via facies distribution and lacustrine fluctuation. The insights gained from this study can provide knowledge about the characteristics and associated controlling factors of the reservoirs in the Permian Lower Urho Formation within the western Junggar Basin. These insights can also benefit petroleum reserve and hydrocarbon production exploration in the study area and further petroleum exploration in other areas with similar sedimentary/tectonic settings.","PeriodicalId":51318,"journal":{"name":"Interpretation-A Journal of Subsurface Characterization","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48937138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of Yu’s wavelet and supervirtual seismic refraction interferometry to enhance first arrivals: A case study from Kuche Mountain","authors":"","doi":"10.1190/int-2022-0091.1","DOIUrl":"https://doi.org/10.1190/int-2022-0091.1","url":null,"abstract":"The signal-to-noise ratio (S/N) of the 3D seismic data in Kuche Mountain is poor, where the first-arrival events are overlapped with random and coherent noises due to the data set collected within a challenging environment with abrupt changes in the topographical elevation. Therefore, it is difficult to carry out first-arrival picking, which in turn affects the application of tomographic inversion and static correction in this area. To face this challenge, first-arrival filtering using Yu’s wavelet and first-arrival enhancement with supervirtual seismic refraction interferometry are applied in 3D seismic data processing on the data set collected from the Kuche Mountain area. The result finds that, by using these two techniques together, the first-arrival events can be recognized easily, the first-arrival times can be picked accurately, and the amount of picked events increases greatly.","PeriodicalId":51318,"journal":{"name":"Interpretation-A Journal of Subsurface Characterization","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48368652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characteristics of Permian Igneous Rocks and their Petroleum Geology Implications in the Northern Part of Central Sichuan, Sichuan Basin, China","authors":"Lei Tan, Hong Liu, Gang Zhou, Song Tang, Yunxian Zeng, M. Li, Minglong Li, Dan Hu","doi":"10.1190/int-2022-0079.1","DOIUrl":"https://doi.org/10.1190/int-2022-0079.1","url":null,"abstract":"Based on data from cores, cuttings, thin sections, and logging and seismic activities, the lithofacies, geophysical response, and spatial distribution characteristics of the Permian igneous rocks in the northern part of central Sichuan were analyzed and summarized. Furthermore, the eruption and filling processes of the igneous rocks were restored, and the hydrocarbon geologic significance of the volcanic eruption events was investigated. The results reveal that the igneous rocks in this area are volcanic overflow facies and sedimentary facies, with volcanic lava and pyroclastic rocks developed. Only one eruption cycle occurred vertically. The igneous rocks exhibit low natural gamma ray, low acoustic, high compensation neutron logging, high density, and high resistivity logging values. The seismic responses are characterized by multiaxial, flexural, and upward arching. The plane distribution shape is an inverted U, with a nearly east–west linear distribution. The igneous rocks in the area were emplaced via a fissure eruption along the basement faults in the early Longtan. The eruption-filling process can be roughly divided into four stages: the deposition of the Maokou Formation, the geomorphological embryonic stage, the geomorphological differentiation stage, and the volcanic eruption and filling stage. The underdevelopment of primary pores and the lack of dissolution in the later stage led to poor igneous reservoir performance, which limits the igneous reservoir hydrocarbon exploration prospect. However, the early faulting activity resulted in the differentiation of the Maokou Formation sedimentary and karst landforms. The thermodynamic conditions created by the later eruption of the igneous rocks, sufficient Mg2+ sources, and favorable geomorphological units laid a good foundation for the development of the dolomite reservoirs in the Maokou Formation. Among them, the karst slopes and highland areas of the Maokou Formation along the two sides of the strip of igneous rocks are dominant areas for the development of the dolomite reservoirs in the Maokou Formation.","PeriodicalId":51318,"journal":{"name":"Interpretation-A Journal of Subsurface Characterization","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49453398","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simultaneous seismic inversion study for channel sandstone identification, northern part of the Eastern Shelf, King County, North-Central Texas","authors":"O. Ogiesoba, Sarp Karakaya, Trey Cortez","doi":"10.1190/int-2022-0096.1","DOIUrl":"https://doi.org/10.1190/int-2022-0096.1","url":null,"abstract":"This paper documents the results of a prestack simultaneous seismic inversion conducted to investigate the Wolfcampian lower Tannehill sandstone channels within a mixed carbonate siliciclastic system in the northern Eastern Shelf in King County, North Central Texas. Previous exploration methods for the Tannehill sandstone were based largely on well-log correlation which, because of their widely spaced sample points, are not optimal for channel delineation. We have generated crossplots of P- and S-wave velocity ratios ( VP/ VS ratios) versus P-impedance to determine lithologic types. We then used 3D seismic data and wireline logs to implement a prestack simultaneous seismic inversion procedure to generate P- and S-impedances, density, and VP/ VS ratio volumes to identify the valley-fill Tannehill lowstand systems. Our results find that (1) based on impedance and density, the sandstone-rich channels can be easily separated from the carbonate-rich zones but are difficult to distinguish using VP/ VS. (2) Although there appeared to be several channel systems in the area of investigation, two of these, hereby referred to as channel A and channel B, are recognized to be the key contributors of sandstone sediments to the shelf edge, slope, and basin areas. (3) Of these two channels, channel A is the larger and highly sinuous; it is associated with a meander loop, a point bar, and an abandoned channel. At the point-bar location, channel A has a width of 890 m (2920 ft) and a depth of 29 m (94 ft). The point bar is structurally anticlinal and thus constitutes a potential exploration target. In contrast, channel B is less sinuous, without any associated point bar. It has a maximum depth and width of 23 m (75 ft) and 270 m (886 ft), respectively. Finally, the inversion results suggest that other potential Tannehill sandstone reservoirs may still be present elsewhere within King County.","PeriodicalId":51318,"journal":{"name":"Interpretation-A Journal of Subsurface Characterization","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43650467","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Introduction to special section: Distributed fiber optic sensing","authors":"Shuang Zhang, V. Jayaram, G. Jin, V. Kazei, Yongzan Liu, A. Titov, M. Zeidouni, D. Zhu","doi":"10.1190/int-2023-0315-spseintro.1","DOIUrl":"https://doi.org/10.1190/int-2023-0315-spseintro.1","url":null,"abstract":"<jats:p> </jats:p>","PeriodicalId":51318,"journal":{"name":"Interpretation-A Journal of Subsurface Characterization","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43798686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Amplitude variation with incidence and azimuth stepwise inversion with coherence-attribute-constraints for anisotropic parameters","authors":"L. Ji, Z. Zong, Kun Luo","doi":"10.1190/int-2022-0106.1","DOIUrl":"https://doi.org/10.1190/int-2022-0106.1","url":null,"abstract":"With the development of 5D seismic technology, the stable acquisition of anisotropy information from wide-azimuth seismic data has become a key scientific problem in the seismic inversion of fractured reservoirs. However, existing AVAZ inversion methods suffer from too many parameters to be estimated, large variation in contribution, and unstable inversions. Therefore, we develop an AVAZ inversion method with coherent attribute constraints to solve the problem of unstable inversion of anisotropic parameters. First, we use seismic coherent attributes to build a fracture equivalent probability model containing anisotropic information of the subsurface medium, which is used to simulate large-scale subsurface fractures and faults, thereby improving the reliability and stability of the anisotropic parameter inversion. We carry out the AVAZ inversion method in a Bayesian framework using wide-azimuth seismic data and introduce smoothing background model constraints to reduce the dependence of the inversion on the initial model and improve the stability of the inversion. Moreover, we add Gaussian and fracture probability distribution models to the objective function to improve the reasonableness and stability of the inversion. Then, through the analysis of the contribution of the estimated parameters, we found that the contribution of the isotropic parameters to the reflection coefficient is much larger than that of the anisotropic parameters to the reflection coefficient. Therefore, we developed a stepwise optimization-seeking inversion method for the isotropic and anisotropic parameters, which can reduce the number of the estimated parameters and thus improve the stability of the inversion of the anisotropic parameters. Field data show that this method produces suitable inversion results even at moderate levels of noise. Therefore, we can conclude that the proposed method has good applicability and stability in predicting the anisotropy parameters of fractured shale reservoirs.","PeriodicalId":51318,"journal":{"name":"Interpretation-A Journal of Subsurface Characterization","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47007756","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ultra-Deep Carbonate Reservoir Lithofacies Classification Based on Deep Convolutional Neural Network (CNN)- A Case Study in Tarim Basin, China","authors":"Sheng-yu Lu, Chuyang Cai, Zhi Zhong, Zhongxian Cai, Xu Guo, Zhang Heng, Jie Li","doi":"10.1190/int-2022-0020.1","DOIUrl":"https://doi.org/10.1190/int-2022-0020.1","url":null,"abstract":"Lithofacies identification is essential in reservoir evaluation, especially in ultradeep carbonate reservoirs. Generally, coring samples are the best sources to identify carbonate lithofacies because they were taken directly from reservoirs. However, core is expensive to obtain, and it is generally greatly limited in its availability. In recent years, deep learning has attracted enormous attention because of its robust nonlinear regression and classification ability. This study applies a deep learning algorithm to identify the lithofacies using geophysical well log data. Six types of well log data, including natural gamma-ray (GR), density (DEN), neutron porosity (CNL), acoustic (AC), and shallow and deep lateral resistivity well logs (RT/RXO), are smoothed by the average sliding method and converted to 2D data. Then, the two-dimensional data are treated as inputs to predict the carbonate lithofacies through the convolutional neural network (CNN). The results indicate that the prediction accuracy rate is 90.2%. It shows that the convolutional neural network can well identify different carbonate lithofacies.","PeriodicalId":51318,"journal":{"name":"Interpretation-A Journal of Subsurface Characterization","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48741818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Anomalous elastic properties of mudrocks bounding reservoirs with high concentrations of naturally occurring CO2","authors":"M. Sams, T. Jayasangar","doi":"10.1190/int-2022-0115.1","DOIUrl":"https://doi.org/10.1190/int-2022-0115.1","url":null,"abstract":"Very high concentrations of CO2 have been encountered in solution as carbonic acid in hydrocarbon reservoirs in parts of the Greater Sarawak Basin, offshore Borneo, Malaysia. Concentrations can exceed 80%. Anomalous features in 3D seismic data also are found in areas with high CO2 concentrations. These features appear as halos around reservoirs, cutting across stratigraphy and indicating a hardening of the nonreservoir rocks within the envelope of the halo. These halos can extend for hundreds of meters above and below a reservoir. Elastic log data from wells that pass through and adjacent to these seismic anomalies indicate that mudrocks within the anomalies have higher densities and velocities than would be predicted from locally derived compaction trends. Combinable magnetic resonance measurements indicate that the anomalous properties are the result of lower-than-expected capillary-bound microporosities. It is proposed that carbonic acid in the reservoir fluids diffuses into the bounding rocks, causing a loss of porosity. The amount of porosity lost depends on the clay content of the mudrock and the initial level of compaction, with shallower, more clay-rich shales able to lose more porosity. The anomalous seismic signatures result from a sharp transition (over approximately 5 m) at the diagenetic front between normal and altered rocks. The alteration can significantly change the amplitude variation with offset response of the reservoirs and therefore the ability to correctly predict fluid phase and reservoir quality. No anomalies are observed when the concentration of CO2 in the reservoir is less than 10% but always present when CO2 exceeds 20%. Therefore, it is possible to map the general distribution of high CO2 concentration from seismic data. There is no indication that the scale, amplitude, or shape of the anomalies gives an indication of the concentration of CO2.","PeriodicalId":51318,"journal":{"name":"Interpretation-A Journal of Subsurface Characterization","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46284870","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reservoir characteristics of lacustrine mixed siliciclastic-carbonate sedimentary rocks: A case study of the Paleogene Funing 2lt;supgt;ndlt;/supgt; Member in Subei Basin, China","authors":"Wei Li, Xiaomin Zhu, Qidong Liu","doi":"10.1190/int-2022-0044.1","DOIUrl":"https://doi.org/10.1190/int-2022-0044.1","url":null,"abstract":"Unique lacustrine mixed siliciclastic-carbonate sedimentary rocks accumulated during deposition of the second member of the Paleogene Funing Formation in the Jinhu Sag and Gaoyou Sag, Subei Basin, which has significant scientific and petroleum exploration values. The reservoir characteristics of the deposits were summarized by means of core observation, petrographic analyses, scanning electron microscope analysis, porosity and permeability tests, carbonate content measurement and X-ray diffraction clay mineral analyses. These special deposits consisting of siliciclastics and allochems were mainly found in a shallow lake at the front and side of deltas, and were also found in gravity flow deposits of a deep lake. The results show that lithology and dissolution of early calcite cements together influence the reservoir performance. From a sedimentological perspective, two types of lacustrine deposits are present in the study area. The first one preserves massive or graded bedding composed of allochems (ooids and intraclasts) and siliciclastics (mainly quartz) of various grain sizes, as well as marl; this type of reservoir is poorly sorted. The second one preserves wavy cross-lamination composed of ooids and quartz of similar size; this type of reservoir is well sorted. The diagenesis of reservoirs in the study area mainly includes compaction, cementation and dissolution. Reservoirs with massive or graded bedding were impacted by compaction, with current porosity less than 5%. Reservoirs with wavy cross-lamination could form high-quality reservoirs with porosity up to 22%, in which secondary dissolution pores represent the main type of porosity. The early calcite cementation may have inhibited compaction prior to the formation of solution vugs and the formation of high-quality reservoirs.","PeriodicalId":51318,"journal":{"name":"Interpretation-A Journal of Subsurface Characterization","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43603532","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Challenges and Best Practices in Interpreting Cross-well Strain Signals to Monitor Multi-Crew Zipper Fracturing Operations","authors":"Yanrui Ning, G. Jin","doi":"10.1190/int-2022-0092.1","DOIUrl":"https://doi.org/10.1190/int-2022-0092.1","url":null,"abstract":"Cross-well strain measurements using Low-frequency Distributed Acoustic Sensing (LF-DAS) is an emerging technique to monitor hydraulic fracture propagation. The qualitative interpretations of the strain rate data have been used to evaluate the fracturing stimulation efficiency, hydraulic fracture geometry, and cross-well communication. Limited studies have investigated the cross-well strain signals recorded from offset fibers during zipper fracturing treatment, though zipper fracturing becomes a routine method of stimulating horizontal wells in unconventional reservoirs. This gap will be filled in this research by presenting the methods we developed to investigate complicated LF-DAS signals. These approaches were further demonstrated using field datasets recorded along the two temporal sensing fiber cables during the zipper fracturing operation of seven offset wells with two fracking crews operating simultaneously. By exploring, comparing, and presenting the LF-DAS data recorded in wireline and disposable fiber cables, this research shares the best practices for visualizing and interpreting cross-well strain signals. The LF-DAS dataset shown in this study, which, to the best of our knowledge, is one of the most complicated LF-DAS datasets presented. The approaches proposed here can be extended and applied to visualize and interpret different kinds of complicated LF-DAS signals recorded using permanent, wireline, and disposable fiber cables.","PeriodicalId":51318,"journal":{"name":"Interpretation-A Journal of Subsurface Characterization","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42876912","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}