Seismic characterisation of carbonate platforms and reservoirs: an introduction and review

AbstractImproved seismic data quality in the last 10–15 years, innovative use of seismic attribute combinations, extraction of geomorphological data, and new quantitative techniques, have significantly enhanced understanding of ancient carbonate platforms and processes. 3D data have become a fundamental toolkit for mapping carbonate depositional and diagenetic facies and associated flow units and barriers, giving a unique perspective how their relationships changed through time in response to tectonic, oceanographic and climatic forcing. Sophisticated predictions of lithology and porosity are being made from seismic data in reservoirs with good borehole log and core calibration for detailed integration with structural, paleoenvironmental and sequence stratigraphic interpretations. Geologists can now characterise entire carbonate platform systems and their large-scale evolution in time and space, including systems with few outcrop analogues such as the Lower Cretaceous Central Atlantic “Pre-Salt” carbonates. The papers introduced in this review illustrate opportunities, workflows, and potential pitfalls of modern carbonate seismic interpretation. They demonstrate advances in knowledge of carbonate systems achieved when geologists and geophysicists collaborate and innovate to maximise the value of seismic data from acquisition, through processing to interpretation. Future trends and developments, including machine learning and the significance of the energy transition, are briefly discussed.

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Pitfalls and limitations in seismic attribute interpretation of tectonic features

Interpretation ◽

10.1190/int-2014-0122.1 ◽

2015 ◽

Vol 3 (1) ◽

pp. SB5-SB15 ◽

Cited By ~ 64

Author(s):

Kurt J. Marfurt ◽

Tiago M. Alves

Keyword(s):

Seismic Data ◽

Seismic Attributes ◽

Seismic Attribute ◽

3D Data ◽

Amplitude Data ◽

Seismic Sections ◽

Push Down ◽

Data Coherence ◽

Level Of Experience ◽

Tectonic Features

Seismic attributes are routinely used to accelerate and quantify the interpretation of tectonic features in 3D seismic data. Coherence (or variance) cubes delineate the edges of megablocks and faulted strata, curvature delineates folds and flexures, while spectral components delineate lateral changes in thickness and lithology. Seismic attributes are at their best in extracting subtle and easy to overlook features on high-quality seismic data. However, seismic attributes can also exacerbate otherwise subtle effects such as acquisition footprint and velocity pull-up/push-down, as well as small processing and velocity errors in seismic imaging. As a result, the chance that an interpreter will suffer a pitfall is inversely proportional to his or her experience. Interpreters with a history of making conventional maps from vertical seismic sections will have previously encountered problems associated with acquisition, processing, and imaging. Because they know that attributes are a direct measure of the seismic amplitude data, they are not surprised that such attributes “accurately” represent these familiar errors. Less experienced interpreters may encounter these errors for the first time. Regardless of their level of experience, all interpreters are faced with increasingly larger seismic data volumes in which seismic attributes become valuable tools that aid in mapping and communicating geologic features of interest to their colleagues. In terms of attributes, structural pitfalls fall into two general categories: false structures due to seismic noise and processing errors including velocity pull-up/push-down due to lateral variations in the overburden and errors made in attribute computation by not accounting for structural dip. We evaluate these errors using 3D data volumes and find areas where present-day attributes do not provide the images we want.

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About this title - Seismic Characterization of Carbonate Platforms and Reservoirs

Geological Society London Special Publications ◽

10.1144/sp509 ◽

2021 ◽

Vol 509 (1) ◽

pp. NP-NP

Author(s):

J. Hendry ◽

P. Burgess ◽

D. Hunt ◽

X. Janson ◽

V. Zampetti

Keyword(s):

Seismic Data ◽

Oil And Gas ◽

Carbonate Platform ◽

Carbonate Platforms ◽

Oil And Gas Exploration ◽

Seismic Modelling ◽

Flow Units ◽

Development Data ◽

Seismic Characterization

Modern seismic data have become an essential toolkit for studying carbonate platforms and reservoirs in impressive detail. Whilst driven primarily by oil and gas exploration and development, data sharing and collaboration are delivering fundamental geological knowledge on carbonate systems, revealing platform geomorphologies and how their evolution on millennial time scales, as well as kilometric length scales, was forced by long-term eustatic, oceanographic or tectonic factors. Quantitative interrogation of modern seismic attributes in carbonate reservoirs permits flow units and barriers arising from depositional and diagenetic processes to be imaged and extrapolated between wells.This volume reviews the variety of carbonate platform and reservoir characteristics that can be interpreted from modern seismic data, illustrating the benefits of creative interaction between geophysical and carbonate geological experts at all stages of a seismic campaign. Papers cover carbonate exploration, including the uniquely challenging South Atlantic pre-salt reservoirs, seismic modelling of carbonates, and seismic indicators of fluid flow and diagenesis.

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THE INTEGRATION OF MODERN TECHNOLOGY IN GIPPSLAND'S CENTRAL FIELDS STUDY

The APPEA Journal ◽

10.1071/aj93041 ◽

1994 ◽

Vol 34 (1) ◽

pp. 513

Author(s):

P.V.Hinton P.V.Hinton ◽

M.G.Cousins ◽

P.E.Symes

Keyword(s):

Seismic Data ◽

Field Performance ◽

Simulation Models ◽

Modern Technology ◽

Depositional Environments ◽

Seismic Attribute ◽

Sequence Stratigraphic ◽

Multidisciplinary Study ◽

Attribute Analysis ◽

Definition Of

The central fields area of the Gippsland Basin, Australia, includes the Halibut, Cobia, Fortescue, and Mackerel oil fields. These large fields are mature with about 80% of the reserves produced. During 1991 and 1992 a multidisciplinary study, integrating the latest technology, was completed to help optimise the depletion of the remaining significant reserves.A grid of 4500 km of high resolution 3D seismic data covering 191 square kilometres allowed the identification of subtle structural traps as well as better definition of sandstone truncation edges which represent the ultimate drainage points. In addition, the latest techniques in seismic attribute analysis provided insight into depositional environments, seal potential and facies distribution. Sequence stratigraphic concepts were used in combination with seismic data to build complex multi million cell 3D geological models. Reservoir simulation models were then constructed to history match past production and to predict future field performance. Facility studies were also undertaken to optimise depletion strategies.The Central Fields Depletion Study has resulted in recommendations to further develop the fields with about 80 work-overs, 50 infill wells, reduction in separator pressures, and gas lift and water handling facility upgrades. These activities are expected to increase ultimate reserves and production. Some of the recommendations have been implemented with initial results of additional drilling on Mackerel increasing platform production from 22,000 BOPD to over 50,000 BOPD. An ongoing program of additional drilling from the four platforms is expected to continue for several years.

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Morphology, architecture, and evolutionary processes of the Zhongjian Canyon between two carbonate platforms, South China Sea

Interpretation ◽

10.1190/int-2017-0222.1 ◽

2018 ◽

Vol 6 (4) ◽

pp. SO1-SO15 ◽

Cited By ~ 1

Author(s):

Yintao Lu ◽

Wei Li ◽

Shiguo Wu ◽

Bryan T. Cronin ◽

Fuliang Lyu ◽

...

Keyword(s):

Seismic Data ◽

Large Scale ◽

Middle Miocene ◽

Sedimentary Environment ◽

Submarine Canyon ◽

High Amplitude ◽

Seismic Facies ◽

Coarse Grained ◽

Carbonate Platforms ◽

Depositional Processes

Two isolated Neogene carbonate platforms (Xisha and Guangle carbonate platforms) have developed in the rifted uplifts since the Early Miocene. A large-scale submarine canyon system, the Zhongjian Canyon (ZJC), has developed in the tectonic depression between the two platforms since the Middle Miocene. High-resolution bathymetry data and 2D and 3D seismic data reveal the existence of the ZJC on the present seafloor, as well as in Neogene intervals. It exhibits typical characteristics of deepwater canyons that cut the surrounding rocks and indicate strong erosional features. The ZJC resulted from northwest–southeast strike-slip fault activities during synrift and postrift stages, and it periodically grew during the development of carbonate platforms since the Middle Miocene. We identified four cycles of parallel to subparallel high amplitude and dim reflectors in seismic data, which we interpreted as alternating canyon fill, based on the interpretation of seismic facies. Thus, the sedimentary evolution of the ZJC can be divided into four typical stages, which were in the Middle Miocene, Late Miocene, Early Pliocene, and Pleistocene. Considering the tectonic background of the carbonate platforms, as well as the on-going igneous activities, the sediment filling the canyon could be derived from a mixture of carbonate clasts, igneous clasts, mud, and silt. The laminar high-amplitude reflectors and dim-reflector package represented a fining-upward sedimentary cycle. The coarse-grained sediment in canyon fillings could be turbidites, carbonate debrites, and even igneous clasts. In contrast, the fine-grained sediment is likely to be dominated by pelagic to hemipelagic mud, and silt. This case study describes a deepwater canyon under a carbonate-dominated sedimentary environment and has significant implications for improving our knowledge of periplatform slope depositional processes. Furthermore, the insight gained into periplatform slope depositional processes can be applied globally.

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Estimating Caprock Impact on CO2 Migration in the Gassum Formation Using 2D Seismic Line Data

Transport in Porous Media ◽

10.1007/s11242-021-01622-1 ◽

2021 ◽

Author(s):

Odd Andersen ◽

Anja Sundal

Keyword(s):

Seismic Data ◽

Large Scale ◽

Flow Simulation ◽

Small Scale ◽

Model Parameters ◽

Seismic Line ◽

Migration Direction ◽

3D Data ◽

And Migration ◽

The Impact

AbstractRealizable CO2 storage potential for saline formations without closed lateral boundaries depends on the combined effects of physical and chemical trapping mechanisms to prevent long-term migration out of the defined storage area. One such mechanism is the topography of the caprock surface, which may retain CO2 in structural pockets along the migration path. Past theoretical and modeling studies suggest that even traps too small to be accurately described by seismic data may play a significant role. In this study, we use real but scarce seismic data from the Gassum Formation of the Norwegian Continental shelf to estimate the impact of topographical features of the top seal in limiting CO2 migration. We seek to estimate the amount of macro- and sub-scale trapping potential of the formation based on a few dozen interpreted 2D seismic lines and identified faults. We generate multiple high-resolution realizations of the top surface, constructed to be faithful to both large-scale topography and small-scale statistical properties. The structural trapping and plume retardation potential of these top surfaces is subsequently estimated using spill-point (static) analysis and dynamical flow simulation. By applying these techniques on a large ensemble of top surface realizations generated using a combination of stochastic realizations and systematic variation of key model parameters, we explore the range of possible impacts on plume advancement, physical trapping and migration direction. The stochastic analysis of trapping capacity and retardation efficiency in statistically generated, sub-seismic resolution features may also be applied for surfaces generated from 3D data.

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Seismic Attribute-Aided Characterization of Margin Backstepping and Advance along Isolated Carbonate Sequences, Sirt Basin, Libya

AL-MUKHTAR JOURNAL OF SCIENCES ◽

10.54172/mjsc.v36i4.590 ◽

2021 ◽

Vol 36 (4) ◽

pp. 280-287

Author(s):

Muneer A. Abdalla

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Carbonate Platform ◽

Seismic Attributes ◽

Sea Level Changes ◽

Carbonate Platforms ◽

Seismic Attribute ◽

Stratigraphic Sequences ◽

Sirt Basin

Isolated carbonate platforms are common and contain significant hydrocarbon accumulations, particularly in the tectonically complex Sirt Basin in Libya. This study investigates the margin cyclicity of two carbonate stratigraphic sequences developed on an isolated carbonate platform in the NW Sirt Basin using 3-D post-stack seismic volume and wireline log data. The two sequences (sequences 4 and 5) are bounded by unconformity surfaces from the base and top. Seismic attributes show that each sequence displays a cycle of margin backstepping followed by margin advance for several hundred meters. This study concludes that the margin backstepping and advance are mainly influenced by sea-level changes. A rapid sea-level rise caused the backstepping, whereas slow sea-level rise caused the margin advance.

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Geopressure prediction using seismic data: Current status and the road ahead

Geophysics ◽

10.1190/1.1527101 ◽

2002 ◽

Vol 67 (6) ◽

pp. 2012-2041 ◽

Cited By ~ 120

Author(s):

N. C. Dutta

Keyword(s):

Seismic Data ◽

Large Scale ◽

Best Practice ◽

Seismic Velocity ◽

Rock Physics ◽

Rock Properties ◽

Current Status ◽

Seismic Attribute ◽

Attribute Analysis ◽

Exploration And Production

The subject of seismic detection of abnormally high‐pressured formations has received a great deal of attention in exploration and production geophysics because of increasing exploration and production activities in frontier areas (such as the deepwater) and a need to lower cost without compromising safety and environment, and manage risk and uncertainty associated with very expensive drilling. The purpose of this review is to capture the “best practice” in this highly specialized discipline and document it. Pressure prediction from seismic data is based on fundamentals of science, especially those of rock physics and seismic attribute analysis. Nonetheless, since the first seismic application in the 1960s, practitioners of the technology have relied increasingly on empiricism, and the fundamental limitations of the tools applied to detect such hazardous formations were lost. The most successful approach to seismic pressure prediction is one that combines a good understanding of rock properties of subsurface formations with the best practice for seismic velocity analysis appropriate for rock physics applications, not for stacking purposes. With the step change that the industry has seen in the application of the modern digital computing technology to solving large‐scale exploration and production problems using seismic data, the detection of pressured formations can now be made with more confidence and better resolution. The challenge of the future is to break the communication and the “language barrier” that still exists between the seismologists, the rock physicists, and the drilling community.

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Challenges of carbonate platform identification and characterisation from seismic data in frontier exploration – evaluating a possible Miocene example from the SE Caribbean

Geological Society London Special Publications ◽

10.1144/sp509-2019-200 ◽

2020 ◽

pp. SP509-2019-200

Author(s):

Álvaro Jiménez Berrocoso ◽

Massimiliano Masini ◽

Josgre Salazar ◽

Antonio Olaiz Campos ◽

Jean C. C. Hsieh

Keyword(s):

Seismic Data ◽

Carbonate Platform ◽

Sources Of Information ◽

Carbonate Platforms ◽

Shallow Marine ◽

Southern Caribbean ◽

Marine Carbonate ◽

Marine Carbonates ◽

Intensive Approach ◽

3D Seismic Data

AbstractThe purpose of this study is to demonstrate that the identification of carbonate platforms in frontier exploration using seismic data remains challenging despite the variety of attributes that can be extracted from the data and their integration with other sources of information. A Miocene example from offshore Tobago (Southern Caribbean) is evaluated using 3D seismic data integrated with regional geology, potential fields, analogues, and structural restoration. The data are compatible with interpreting the target as shallow-marine carbonates, and a conceptual model is presented. However, far fewer of the seismic characteristics are diagnostic of a carbonate platform, and despite the intensive approach and the use of published criteria for subsurface carbonate interpretation, it was impossible to conclusively identify the target as a shallow-marine carbonate. Alternative explanations such as volcaniclastics, eroded remnants of siliciclastics and basement highs are considered. The study illustrates that it is common to find situations where the origin of a prospective geobody cannot be determined beyond significant levels of uncertainty unless it is drilled. If other elements of the petroleum system are favourable, this irreducible risk has to be accepted to avoid overlooking attractive carbonate reservoirs, provided all available data are used and all possible alternative interpretations considered.

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Delineation of Carbonate Buildups Using Advanced Seismic Attributes, NW Sirte Basin, Libya

Libyan Journal of Basic Sciences ◽

10.36811/ljbs.2021.110078 ◽

2021 ◽

pp. 159-168

Author(s):

Muneer Abdalla

Keyword(s):

Seismic Data ◽

Carbonate Platform ◽

Median Filter ◽

Random Noise ◽

Seismic Attributes ◽

Small Scale ◽

Seismic Attribute ◽

Attribute Analysis ◽

Data Conditioning ◽

Sirte Basin

The Paleocene reservoir formations of the Northwest Sirte Basin in North-central, Libya contains chaotic and mound-shaped seismic geometries that may have an impact on the performance of the reservoirs. It is crucial to characterize and interpret these complex geometries for future field development. Therefore, this study was utilized numerous seismic attributes to characterize and enhance the interpretation of the chaotic and mounded geometries. Data conditioning represented by spectral whitening and median filter was first applied to enhance the quality of the seismic data and remove random noise resulted from data acquisition and processing. It provided high-resolution seismic data and better-displayed edges and sedimentological features. Variance, root mean square (RMS), curvature, and envelope attributes were computed from the post-stack 3D seismic data to better visualize and interpret the chaotic and mound-like seismic geometries. Based on the seismic attribute analysis, the chaotic facies were interpreted as barrier reefs forming the margins of an isolated carbonate platform, whereas the small-scale mound-shaped facies was interpreted as patch reefs developed on the platform interior. Data conditioning methods and seismic attribute analysis that were applied to the 3-D seismic data have effectively improved the detection and interpretation of the chaotic and mounded facies in the study area. Keywords: Carbonate buildup, data conditioning, seismic attributes, Sirte Basin, Libya

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Cross-profile seismic data acquisition, imaging, and modeling of iron-oxide deposits: A case study from Blötberget, south-central Sweden

Geophysics ◽

10.1190/geo2020-0173.1 ◽

2020 ◽

Vol 85 (6) ◽

pp. B233-B247

Author(s):

Georgiana Maries ◽

Alireza Malehmir ◽

Paul Marsden

Keyword(s):

Iron Oxide ◽

Seismic Data ◽

Large Scale ◽

Seismic Profiles ◽

Data Set ◽

Reflection Seismic ◽

South Central ◽

3D Data ◽

Lateral Extent ◽

3D Processing

Two 2D reflection seismic profiles were acquired in Blötberget, south-central Sweden, for deep targeting and delineation of sheet-like iron-oxide deposits, known to dip toward the southeast and extend down to at least 0.8 km depth from core drilling observations. The two perpendicular profiles recorded shots at every receiver station along the main and cross profiles. To obtain more information on the lateral extent of the mineralized horizons, data from the two profiles, including the cross-profile records, were binned together in a 3D grid and further processed as a 3D data set. Processing results suggest that more information is retrieved when 3D processing is used and the mineralization lateral extent can be inferred for at least 0.3 km. The seismic response of the mineralization was further studied through forward reflection traveltime modeling, using a 3D ray-tracing approach; thus, the 3D geometry of several planar reflectors was validated. Additionally, 2D elastic finite-difference modeling work showed that the observed reflection pattern in the seismic data may originate from several mineralized horizons, suggesting potential resources in the footwall of the known deposits and large-scale geologic structures. The results encourage the use of seismic methods for direct delineation of mineral deposits even from 2D profiles and prompted a 3D survey in the area.

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