Catálogo de publicaciones - revistas

<jats:p> The Editorial Calendar details upcoming publication plans for The Leading Edge. This includes special sections, guest editors, and information about submitting articles to TLE. </jats:p>

<jats:p> Africa is a continent laden with numerous natural resources, from important fluids to critical and rare-earth minerals. This makes Africa a pivotal force in conventional energy production and sustainable low-carbon geoenergy development. The continent's unique position necessitates a continuous influx of proficient geoscientists, particularly geophysicists, to effectively extract and commercialize these subsurface treasures. </jats:p>

<jats:p> The exploration and management of subsurface reservoirs relies heavily on unraveling the intricate complexities of faults and fractures. In this special section, we present a collection of papers that, in the absence of world-class outcrop exposures such as that shown on this issue's cover, utilize various data sets and geophysical processing techniques to illuminate fault and fracture networks. The collected papers address a spectrum of fault- and fracture-related topics pertinent to scientists across disciplines, spanning hydrocarbon plays to geothermal systems and carbon storage sites. </jats:p>

<jats:p> 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. </jats:p>

<jats:p> 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<jats:sup>(S)</jats:sup>. This property is the contrast in the SWS anisotropy parameter, γ<jats:sup>(S)</jats:sup>, 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<jats:sup>(S)</jats:sup> 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<jats:sup>(S)</jats:sup> than P waves. We also review the development of Δγ<jats:sup>(S)</jats:sup> and find that it has been relatively unexploited by the exploration industry. In addition, we demonstrate that Δγ<jats:sup>(S)</jats:sup> 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. </jats:p>

<jats:p> 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 CO<jats:sub>2</jats:sub> 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. </jats:p>

<jats:p> The Central Sumatra Basin is a vast sedimentary basin that has been proven to produce hydrocarbon. The basin comprises several subbasins that are not sufficiently imaged by conventional seismic reflection profiles and limited well-log data, particularly in the nearshore area to the east. This research aims to delineate sedimentary subbasins, interpret the subsurface geologic model, and identify geologic structures beneath the eastern part of the Central Sumatra Basin using integrated geophysical gravity, seismic profiles, and well-log data. Three-dimensional gravity inversion modeling results indicate that the pre-Tertiary granitic basement is a continental crust with a mass density value of 2.67 gr/cc. The modeling results indicate that the sedimentary rock is composed of Early Oligocene–Middle Miocene sedimentary rock, with a mass density of 2.35 gr/cc, arranged from bottom to top. The residual gravity anomaly model identifies 13 sedimentary subbasins with structural features such as basement height, graben, and fault mapped in a relatively northwest–southeast direction. Moreover, based on the graben pattern and the basement high beneath the eastern Central Sumatra Basin, many structural patterns support the development of petroleum systems similar to that of the western part of the basin, which has already produced hydrocarbon. Our research also revealed the thickness of the Sihapas Formation in the eastern part of the basin, which shows great potential as a hydrocarbon reservoir. The results show that integrated analysis of many geophysical data sets can substantially decrease the uncertainty associated with individual data sets and produce more reliable imaging of subsurface geology. </jats:p>

<jats:p> 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 m<jats:sup>3</jats:sup> gas, compared to model 370's estimated total mass of 178.52 million bbl oil. </jats:p>

<jats:p> SEG Board of Directors actions from November and December 2023. </jats:p>

<jats:p> Nominees for SEG Board of Directors. </jats:p>