{"title":"Application of a novel geometric seismic attribute for enhancing fault visualization in areas of potential carbon capture and storage","authors":"Diana K. Salazar Florez, Heather Bedle","doi":"10.1190/tle43030165.1","DOIUrl":"https://doi.org/10.1190/tle43030165.1","url":null,"abstract":"Seismic fault interpretation is a critical task for any type of energy industry. Correct fault mapping can be crucial for the success of a project. Common geometric seismic attributes, such as coherence and curvature, are routinely employed to enhance fault visualization in seismic data. However, they can show limitations for subseismic faulting. In this study, we highlight the usefulness of including novel aberrancy attributes for fault identification in multiattribute analysis and unsupervised machine learning (ML) techniques. We compare broadband coherence, curvature, multispectral coherence, and aberrancy when trying to map faults in a potential CO2 storage location. We also compare self-organizing maps and generative topographic mapping techniques when including and excluding aberrancy attributes. Our results show that integrating aberrancy attributes during multiattribute analysis and ML steps considerably enhanced the visualization of lineaments with strikes similar to those of fracture sets seen only with well-log data and that were not clearly captured by the conventional seismic attributes and ML scenarios excluding aberrancy attributes. We demonstrate the potential of these novel geometric seismic attributes to map subseismic faults. We also provide an example that can encourage interpreters to include them in their interpretation workflows.","PeriodicalId":507626,"journal":{"name":"The Leading Edge","volume":"107 18","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140089822","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}
James Gaiser, H. Malcotti, Ranjan Dash, James DiSiena, Gary Murphy
{"title":"Imaging faults and fractures with the difference of fast and slow shear-wave splitting reflectivity, Δγ(S): 3D/9C survey in Midland Basin, West Texas, and 3D/3C survey in Washakie Basin, Wyoming","authors":"James Gaiser, H. Malcotti, Ranjan Dash, James DiSiena, Gary Murphy","doi":"10.1190/tle43030155.1","DOIUrl":"https://doi.org/10.1190/tle43030155.1","url":null,"abstract":"One of the most important applications of shear-wave (S-wave) seismic exploration has been in reservoir fracture characterization. While many advancements have been made over the past 30 years to compute and correct for the long-wavelength kinematics of S-wave splitting (SWS) (fast S-wave polarization directions and slow S-wave time delays), practically no progress has been made in imaging the short-wavelength reflectivity of fractures directly with Δγ(S). This property is the contrast in the SWS anisotropy parameter, γ(S), and represents the reflection amplitude at vertical incidence for changes in fracture density and orientation across an interface. In this article, we examine the Lupin nine-component survey in Midland Basin, Texas, for the technical reliability of imaging fractures in depth with converted P to S waves (PS waves) guided by pure-mode horizontal shear waves and vertical shear waves. Final Δγ(S) amplitude maps for each mode show sensitivity to fractures, faults, and the maximum horizontal stress direction. These maps are computed from the difference between fast and slow S-wave stacks (after SWS analysis and correction) and P-wave amplitude variation with offset gradient stacks. The S-wave difference maps identify an east–west lineament, possibly a strike-slip fault or fracture corridor, that is not observed by P-wave depth slices. Pure-mode S waves and PS waves are orders of magnitude more sensitive to Δγ(S) than P waves. We also review the development of Δγ(S) and find that it has been relatively unexploited by the exploration industry. In addition, we demonstrate that Δγ(S) can be obtained directly from the objective function of the transverse energy to correct for SWS, and show a four-component Alford rotation example from a previous PS-wave survey in the Washakie Basin, Wyoming.","PeriodicalId":507626,"journal":{"name":"The Leading Edge","volume":"122 28","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140090444","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}
{"title":"Prediction of hydrocarbon accumulations using 2D basin and petroleum system modeling: Case studies from Abu Zenima and October fields in the Gulf of Suez, Egypt","authors":"Ahmed Tarshan","doi":"10.1190/tle43030185.1","DOIUrl":"https://doi.org/10.1190/tle43030185.1","url":null,"abstract":"This work aims to elucidate the potential applications of 2D basin and petroleum system modeling (BPSM) software in the assessment of hydrocarbon accumulations. To demonstrate how much information can be inferred regarding the existence of hydrocarbons and their mechanisms of accumulation in the subsurface, 2D BPSM was applied to two seismic sections that were utilized as case studies. The faults and horizons were digitally represented throughout the modeling phase to create the 2D BPSM for both seismic sections. The 2D BPSM construction used the age and lithology of each layer of the model as inputs. The hybrid technique was used to simulate hydrocarbon migration paths. The simulation findings showed that when the depth decreases, the degree of maturity declines, as some parts are characterized by transformation ratios of up to 100%. For the Upper Cretaceous source rock in model ABZ88-18, the levels of vitrinite reflectance (Ro%) are in the maturity phase and provide oil with Ro% values ranging from 0.6% to 1.3%. Whereas, in model 370, the Ro% values range from 0.55% to 1.3%. Based on the results of the modeling, new prospective hydrocarbon accumulations were found. Model ABZ88-18's estimated total mass is 292.9 million bbl oil and 11.49 million m3 gas, compared to model 370's estimated total mass of 178.52 million bbl oil.","PeriodicalId":507626,"journal":{"name":"The Leading Edge","volume":"37 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140084529","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}
{"title":"Fault locking and alternate fault activity revealed by simple tools and approaches — Examples from the Western Canadian Sedimentary Basin with implications for hydrocarbon exploration and production","authors":"Jean-Yves Chatellier","doi":"10.1190/tle43030145.1","DOIUrl":"https://doi.org/10.1190/tle43030145.1","url":null,"abstract":"The geology toolkit that is used to reveal faults and fractures is much wider than before. This is due to 3D and 4D views in exploratory statistics programs and to the availability of user-friendly GIS software. These tools allow us to visualize a multitude of parameters that will be briefly explored here. A review of many geologic and nongeologic parameters led to evidence of fault locking and alternate fault activity. It also resulted in new structural models for the Western Canadian Sedimentary Basin (WCSB). The presented data sets include earthquakes, drilling, production, well data, aeromagnetic data, and more. Various integrated approaches reveal well-defined fault patterns that are typical of a strike-slip regime and the existence of previously unrecognized detachments that are important for hydrocarbon exploration. Some of the new geometries and associated mechanisms are illustrated here with outcrop analogues and present-day cross sections, maps, and 3D views. Only the most recent of the two identified strike-slip regimes is covered in this paper. Some emphasis is given to the recognition of detachments at various scales. Among these is the importance of megadetachments displacing the sedimentary cover by up to 16 km with respect to the aeromag. Hence, there is a need for reconstruction before making conclusions. The WCSB has a lot more to offer to explorers who understand faults, fractures, and migration paths. Integrating many types of information in map or 3D views offers new tools to identify and characterize faults.","PeriodicalId":507626,"journal":{"name":"The Leading Edge","volume":"2 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140083395","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}
{"title":"Quantitative seismic fracture characterization of a sandstone reservoir — Decatur, Illinois Basin","authors":"Debasis Chaudhuri, Ankur Roy","doi":"10.1190/tle43020125.1","DOIUrl":"https://doi.org/10.1190/tle43020125.1","url":null,"abstract":"The Illinois Basin Decatur Project, a carbon capture and sequestration task, was undertaken to sequester 1 million tonnes of CO2 into a sandstone reservoir. A 3D seismic survey was conducted to characterize the reservoir. A geomodel was developed from seismic data, inversion results, and well data to geostatistically map the storage potential of the reservoir. However, no fracture model was created or utilized in this exercise. Fractures inherently influence the porosity and permeability of a reservoir. Ignoring them in reservoir characterization is not an optimal reservoir management practice. The image-log interpretation from a few vertical wells drilled in the area shows the bedding plane dips, but no fracture has been identified. However, the lack of fracture crossings in a few vertical wells does not imply that a formation is devoid of fractures altogether. Hence, seismic fracture characterization (leveraging the dense 3D seismic data) is necessary for a reservoir characterization exercise. We utilized the publicly available Decatur 3D seismic data set to run a seismic fracture characterization workflow to delineate potential fracture corridors present in the reservoir. We calculated three edge detection attributes (structural tensor, structure-oriented semblance, and structural dip) in combination to delineate the fracture lineaments. Our workflow extracts several quantitative measures of the seismic lineaments such as dip, azimuth, area, and length, which can be analyzed statistically. The principal focus of this work is to find a way forward to integrate the fractures from seismic data in a geologic model that can be utilized in simulations. Based on our interpretation of seismic fractures, we created a discrete fracture network that can be a building block for creating a finer-resolution fracture model. We also explored the fractal characteristics of seismic-derived fracture lineaments as a way forward for generating discrete fracture networks.","PeriodicalId":507626,"journal":{"name":"The Leading Edge","volume":"75 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139832632","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}
David L. Alumbaugh, Julia Correa, Preston Jordan, Brigitte Petras, Sahchit Chundur, William Abriel
{"title":"An assessment of the role of geophysics in future U.S. geologic carbon storage projects","authors":"David L. Alumbaugh, Julia Correa, Preston Jordan, Brigitte Petras, Sahchit Chundur, William Abriel","doi":"10.1190/tle43020072.1","DOIUrl":"https://doi.org/10.1190/tle43020072.1","url":null,"abstract":"Geologic carbon storage (GCS) is ramping up worldwide as a viable component of carbon capture, utilization, and storage (CCUS) projects aimed at reducing greenhouse pollution to limit climate change. GCS may be a growth opportunity for the application of geophysics in reservoir characterization and monitoring. Federal and state government financial incentives are the economic motivators of the CCUS business in the United States, and recent increases in these incentives have triggered a large number of U.S. Environmental Protection Agency Class VI permit applications to inject CO2 for GCS. The applications indicate that almost all such projects propose using geophysical technology for monitoring. We assessed the GCS geophysical market in the United States based on an intensive analysis of recently filed Class VI permit applications. The analysis shows that reprocessing of existing seismic data will be the primary geophysical activity for reservoir characterization prior to CO2 injection. For monitoring, verification, and recording of CO2 injection, time-lapse vertical seismic profiling and 3D seismic imaging will be the dominant technologies followed by 2D time-lapse seismic imaging and some nonseismic methods. Passive seismic monitoring is planned for the majority of CCUS projects to reduce the risk of induced seismicity. If assumptions related to the United States meeting its current climate goals by 2050 are met, then geophysical activity will increase over the next 30 years. An estimate of the seismic crew count needed to support the projects suggests that the scale of GCS-related seismic acquisition by 2050 may reach the current level of onshore oil and gas geophysics crews in the United States. While the economic incentives of a regulation-driven market will press for the minimization of geophysical sensing in GCS, there is also the potential for growth in geophysical activity with the development of advanced processing and analysis tools, multiphysics data interpretation, and cost-effective continuous monitoring.","PeriodicalId":507626,"journal":{"name":"The Leading Edge","volume":"13 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139883523","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}
A. Ramdani, A. Perbawa, Andrey Bakulin, V. Vahrenkamp
{"title":"3D geophysical image translated into photorealistic virtual outcrop geology using generative adversarial networks","authors":"A. Ramdani, A. Perbawa, Andrey Bakulin, V. Vahrenkamp","doi":"10.1190/tle43020102.1","DOIUrl":"https://doi.org/10.1190/tle43020102.1","url":null,"abstract":"Outcrop analogues play a pivotal role in resolving meter-scale depositional facies heterogeneity of carbonate strata. Two-dimensional outcrops are insufficient to decipher the 3D heterogeneity of carbonate facies. Near-surface geophysical methods, notably ground-penetrating radar (GPR), can be employed to step into 3D and extend the dimensionality of the outcrops to behind the outcrop. However, interpreting geophysical images requires specific geophysical expertise, often unfamiliar to field geologists who are more familiar with the actual rock than the geophysical data. A novel generative adversarial network (GAN) application is presented that constructs a photorealistic 3D virtual outcrop behind-the-outcrop model. The method combines GPR forward modeling with a conditional generative adversarial network (CGAN) and exploits the apparent similarities between outcrop expressions of lithofacies with their radargram counterparts. We exemplified the methodology and applied it to the open-source GPR data acquired from the Late Oxfordian-Early Kimmeridgian Arabian carbonate outcrop. We interpret a 4 km long outcrop photomosaic from a digital outcrop model (DOM) for its lithofacies, populate the DOM with GPR properties, and forward model the synthetic GPR response of these lithofacies. We pair the synthetic GPR with DOM lithofacies and train them using CGAN. Similarly, we pair the DOM lithofacies with outcrop photos and train them using CGAN. We chain the two trained networks and apply them to construct an approximately 2 km long 2D and an approximately 60 m2 3D volume of photorealistic artificial outcrop model. This model operates in a visual medium familiar to outcrop geologists, providing a complementary instrument to visualize and interpret rock formation instead of geophysical signals. This virtual outcrop replicates the visual character of outcrop-scale lithofacies features, such as the intricate bedding contacts and the outline of reef geobodies.","PeriodicalId":507626,"journal":{"name":"The Leading Edge","volume":"100 1-2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139892400","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}
{"title":"3D electrical resistivity survey for reduction of groundwater drilling uncertainties in a clay-rich environment","authors":"John McKnight, Sina Saneiyan","doi":"10.1190/tle43020117.1","DOIUrl":"https://doi.org/10.1190/tle43020117.1","url":null,"abstract":"Drilling for groundwater is expensive and challenging. It is even more challenging to find a location that will result in a high-yield well in heterogeneous environments. To tackle the heterogeneity issue, geophysical surveys can help in mapping the subsurface structure and delineating the drilling trajectory. The current study displays the effectiveness of 3D electrical resistivity tomography (ERT) to locate a permeable groundwater zone within a highly heterogeneous and clayey subsurface. Ground truthing the acquired geophysical data with in-situ sampling helps ensure accuracy in classifying groundwater zones in the final inverted 3D data set while also delineating boundaries between permeable groundwater zones and less permeable clayey structures. In-situ samples of groundwater and soil were used to measure the saturated region's resistivity in the laboratory using a column setup. Clay zones in the data set are classified from the nearby well data at similar depth ranges and from very low resistivity values from ERT data and laboratory measurements. The results display highly differentiating resistivity zones that are attributed to the scattered clay lenses (low resistivity) in conjunction with the freshwater zone (high resistivity). The distinction between clayey and nonclayey bodies is important to better inform drilling locations for optimal groundwater yield. This study concludes that with the aid of low-cost geophysical surveys and minimal in-situ sampling data correlations, permeable groundwater boundaries and clay lens volumes can be identified easily.","PeriodicalId":507626,"journal":{"name":"The Leading Edge","volume":"99 1-2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139876298","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}
{"title":"The portable hand streamer — Rapid seismic imaging for shallow targets","authors":"L. Liberty, L. Otheim","doi":"10.1190/tle43020095.1","DOIUrl":"https://doi.org/10.1190/tle43020095.1","url":null,"abstract":"In this paper, we introduce a portable hand streamer seismic system. The system is appropriate for characterizing the mechanical properties of geologic and engineered materials in the upper 5 to 10 m depth and for reflection imaging from tens to hundreds of meters depth. Unlike other seismic land streamer systems that are typically pulled behind a vehicle with a long string of geophones, our recording system and electric seismic source are contained within an electric utility cart to allow ease of mobility for a single operator. Our 48-channel contact-coupled streamer is tethered to the cart to enable low-effort data collection. Similar to a ground-penetrating radar system, this approach allows rapid data collection on roads, sidewalks, undeveloped paths, and native materials. Signal processing through standard surface- and body-wave approaches follows data collection. We present three case studies where we (1) map Quaternary and older strata to identify active faulting, (2) map shallow bedrock, and (3) identify the footprint of previous subsurface engineered structures. We suggest that this low-cost tool and approach can be used for decameter-scale subsurface site characterization in two or three dimensions. Future advances involve the integration of an autonomous vehicle with a fully programmable seismic source and wholly automated signal processing to enable real-time analysis of shallow seismic data.","PeriodicalId":507626,"journal":{"name":"The Leading Edge","volume":"71 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139884917","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}
{"title":"Editorial Calendar","authors":"","doi":"10.1190/tle43020069.1","DOIUrl":"https://doi.org/10.1190/tle43020069.1","url":null,"abstract":"The Editorial Calendar details upcoming publication plans for The Leading Edge. This includes special sections, guest editors, and information about submitting articles to TLE.","PeriodicalId":507626,"journal":{"name":"The Leading Edge","volume":"54 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139874086","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}