The SEAM Barrett model: strengths and weaknesses

Geophysics ◽  
2021 ◽  
pp. 1-31
Author(s):  
Heloise Lynn ◽  
Colin M. Sayers ◽  
Benjamin Roure
Keyword(s):  
Seismic Data ◽  
Fractured Reservoirs ◽  
Unconventional Reservoirs ◽  
Velocity Variation ◽  
Permian Basin ◽  
Amplitude Variation ◽  
Near Surface ◽  
Reflection Seismic ◽  
The North ◽  
Shale Reservoirs

The SEAM Barrett model was designed to model typical land basins found in the North American mid-continent that host unconventional reservoirs, such as fractured shale reservoirs. This model was used recently in several studies to assess whether shale bodies could be resolved using azimuthal 3D P-P reflection seismic data. In one study it was claimed that near-surface complexity prevents the identification of the shale bodies using azimuthal analysis and concluded that VVAz (Velocity Variation with Azimuth) and AVAz (Amplitude Variation with Azimuth) are not worth running in the Permian basin. However, another study by different authors applied a different seismic processing sequence to successfully resolve the reservoir geobodies and showed promising AVAz and VVAz results. This paper focuses on the SEAM Barrett model itself. Despite some advantages, the limitations of the Barrett model prevent conclusions to be drawn about the usefulness of VVAz and AVAz to characterize fractured reservoirs in other situations, such as the Permian Basin.

Reconstruction of the Reservoir Fine Structure by Using Scattering Attributes

2021 ◽  
Author(s):  
Vladimir Cheverda ◽  
Vadim Lisitsa ◽  
Maksim Protasov ◽  
Galina Reshetova ◽  
Andrey Ledyaev ◽  
...  
Keyword(s):  
Seismic Data ◽  
Numerical Experiments ◽  
Seismic Waves ◽  
Fractured Reservoirs ◽  
Three Dimensional ◽  
Geological Structure ◽  
Discrete Elements ◽  
Digital Twin ◽  
The North ◽  
Slip Surfaces

Abstract To develop the optimal strategy for developing a hydrocarbon field, one should know in fine detail its geological structure. More and more attention has been paid to cavernous-fractured reservoirs within the carbonate environment in the last decades. This article presents a technology for three-dimensional computing images of such reservoirs using scattered seismic waves. To verify it, we built a particular synthetic model, a digital twin of one of the licensed objects in the north of Eastern Siberia. One distinctive feature of this digital twin is the representation of faults not as some ideal slip surfaces but as three-dimensional geological bodies filled with tectonic breccias. To simulate such breccias and the geometry of these bodies, we performed a series of numerical experiments based on the discrete elements technique. The purpose of these experiments is the simulation of the geomechanical processes of fault formation. For the digital twin constructed, we performed full-scale 3D seismic modeling, which made it possible to conduct fully controlled numerical experiments on the construction of wave images and, on this basis, to propose an optimal seismic data processing graph.

Delineation of tunnel valleys across the North Sea coastline, Denmark based on reflection seismic data, boreholes, TEM and Schlumberger soundings

2016 ◽  
Vol 2016 (1) ◽  
pp. 1-10
Author(s):  
Theis Raaschou Andersen ◽  
Flemming Jorgensen ◽  
Steen Christensen
Keyword(s):  
North Sea ◽  
Seismic Data ◽  
Reflection Seismic ◽  
The North ◽  
The North Sea

Empirical observations relating near‐surface magnetic anomalies to high‐frequency seismic data and Landsat data in eastern Sheridan County, Montana

Geophysics ◽  
1991 ◽  
Vol 56 (10) ◽  
pp. 1553-1570 ◽  
Author(s):  
John A. Andrew ◽  
Duncan M. Edwards ◽  
Robert J. Graf ◽  
Richard J. Wold
Keyword(s):  
Seismic Data ◽  
Magnetic Anomalies ◽  
Oil Fields ◽  
Data Types ◽  
Seismic Line ◽  
Near Surface ◽  
The North ◽  
Basement Faults ◽  
Magnetic Basement ◽  
Seismic Sections

Our empirical synergistic correlations of aeromagnetic and seismic data and a Landsat lineament interpretation revealed lineations on the magnetic map that have expression on seismic sections. We observed a conjugate set of northwest‐southeast and northeast‐southwest trending magnetic lineaments (zones which offset and truncate near‐surface magnetic anomalies). We believe these OZs (offset zones) represent lateral faults in a wrench‐fault system. Lateral offsets appear to be 100s of meters to a few kilometers (fractions of a mile to a few miles). We observed a direct correlation between OZs and vertical faults in seismic data. Faults on seismic sections extend from near the surface to near the seismic basement. The faults are most pronounced in the Upper Cretaceous reflectors and seem to disappear with depth. Fault throws are inconsistent (reversing throw across faults). OZs trend northeast‐southwest in the north half of the study area and both northeast‐southwest and northwest‐southeast in the south half. The OZ direction of northeast‐southwest in the north half of the survey is confirmed with seismic data. The northwest‐southeast seismic line contains numerous faults and the northeast‐southwest seismic line contains few faults. Most northeast‐southwest faults do not appear to reach seismic basement and are not seen in an interpretation of the magnetic basement. In two cases, northwest‐southeast OZs and correlative Landsat lineaments coincide with mapped magnetic basement faults. These magnetic basement faults can be seen in seismic data too. Faults trending northwest‐southeast may represent Precambrian faults reactivated during the Laramide Orogeny. Movement along these faults possibly generated the northeast‐southwest faults. Most oil fields have an associated near‐surface magnetic anomaly. Other near‐surface magnetic anomalies occur over obvious, untested (in 1985), seismic character or amplitude anomalies in seismic events which correlate with producing intervals in the oil fields. This synergistic correlation is the most important single observation from our study. Different data types and interpretation techniques identified the same geologic trends and prospective geographical areas. This fundamentally important information is often lost in bickering over which filter or processing technique to use or in arguments over which data type is “more important” than others. Further, if the synergistic correlation of data types were not done, the importance of the anomalous features in each individual data type may not have been recognized.

scholarly journals Deep Structure of the North Natal Valley (Mozambique) Using Combined Wide‐Angle and Reflection Seismic Data

2021 ◽  
Vol 126 (4) ◽  
Author(s):  
A. Leprêtre ◽  
P. Schnürle ◽  
M. Evain ◽  
F. Verrier ◽  
D. Moorcroft ◽  
...  
Keyword(s):  
Seismic Data ◽  
Deep Structure ◽  
Wide Angle ◽  
Reflection Seismic ◽  
The North

SEISMIC DATA PROBLEMS ON COASTAL LIMESTONE, W.A.

1969 ◽  
Vol 9 (1) ◽  
pp. 136
Author(s):  
D. D. Taylor
Keyword(s):  
Seismic Data ◽  
The South ◽  
Reflection Seismic ◽  
The North ◽  
Great Portion

The surface Coastal Limestone in the Perth basin extends from Cape Leeuwin in the South to Geraldton in the north forming a strip along the coast up to 15 miles wide. Over a great portion of this area the reflection seismic results are unreliable. Seismic studies on the limestone disclose some aspects of the problem and indicate ways to improve the quality of the data.

Revitalizing seismic data with new imaging solutions to positively impact field development

2019 ◽  
Vol 38 (1) ◽  
pp. 20-26
Author(s):  
Gareth Venfield ◽  
Michael Townsend ◽  
Paul Cattermole ◽  
Tony Martin ◽  
Stuart Fairhead
Keyword(s):  
Seismic Data ◽  
Model Building ◽  
Large Population ◽  
Waveform Inversion ◽  
Structural Complexity ◽  
Velocity Model ◽  
Near Surface ◽  
Field Development ◽  
The North ◽  
The Right

Evaluating, planning, and forecasting are integral parts of asset development and continue throughout the life cycle of a producing field. The right decisions are required to lower risk and maximize economic recovery in challenging environments. The Claymore Complex is located in the North Sea and was discovered in 1977. A number of geologic challenges affect the imaging and hence field development including a system of shallow interweaving Quaternary channels, numerous high-contrast layers of varying composition, overburden structural complexity, and a sequence of tilted fault blocks containing the main reservoir systems. Historically, seismic processing over the area has not fully solved these challenges, resulting in significant imaging uncertainty. The Claymore Complex has an abundance of data including a large population of well information and interpretation. As part of a data revitalization process, geostatistical integration of these auxiliary data into a velocity model building sequence using full-waveform inversion and wavelet shift tomography enabled the generation of an accurate high-resolution velocity model. Access to a recent 3D survey acquired obliquely to existing data improved subsurface illumination for both the model building and imaging phases. Near-surface imaging effects and their impact on reservoir positioning and clarity were improved using the upgraded velocity model and dual-azimuth data. Shallow imaging challenges were mitigated by utilizing the additional illumination and angular diversity contained within the multiple reverberations. The revitalization of the Claymore area seismic data has challenged the current understanding of the geologic framework. Confidence has been improved by solving depth conversion problems and increasing the understanding of fault positioning and reservoir connectivity, which are invaluable for future field development.

Multidisciplinary study of the hanging wall of the Kiirunavaara iron ore deposit, northern Sweden

Geophysics ◽  
2012 ◽  
Vol 77 (6) ◽  
pp. B269-B285 ◽  
Author(s):  
Mai-Britt Jensen ◽  
Artem Kashubin ◽  
Christopher Juhlin ◽  
Sten-Åke Elming
Keyword(s):  
Seismic Data ◽  
Hanging Wall ◽  
Low Velocity ◽  
Contact Zones ◽  
Near Surface ◽  
Reflection Seismic ◽  
Imaging Results ◽  
Fracture Development ◽  
Weakness Zones ◽  
The Town

Potential weakness zones due to mining-related fracture development under the town of Kiruna, Sweden, have been investigated by integration of seismic, gravity, and petrophysical data. Reflection seismic data were acquired along two subparallel 2D profiles within the residential area of the town. The profiles of [Formula: see text], each oriented approximately east–west, nearly perpendicular to the general strike of the local geology, crossed several contact zones between quartz-bearing porphyries, a sequence of interchanging sedimentary rocks (siltstone, sandstone, conglomerate, and agglomerate), and metabasalt. The resulting reflection seismic sections revealed a strong east-dipping reflectivity that is imaged down to approximately 1.5 km. The location and orientation of major features agree well between the profiles and with the surface geology and known contact zones between the different rock types. Our imaging results, supported by traveltime modelling, indicate that the contact zones dip 40°–50° to the east. The deepest and the weakest reflections are associated with a [Formula: see text] dipping structure that is presumably related to the Kiirunavaara iron mineralization. Tomographic inversion of refracted arrivals revealed a more detailed image of the velocity distribution in the upper 100–200 m along the profiles, enabling us to identify near-surface low velocity zones. These could be possible weakness zones developed along the lithological contacts and within the geologic units. The structural image obtained from the seismic data was used to constrain data inversion along a 28 km long east–northeast to west–southwest-oriented gravity profile. The resulting density model indicates that the quartz-bearing porphyry in the hanging wall of the Kiirunavaara mineralization can be separated into two blocks oriented parallel to the ore body. One block has an unexpected low density, which could be an indication of extensive fracturing and deformation.

Quantifying the uncertainty in an AVO interpretation

Geophysics ◽  
2002 ◽  
Vol 67 (1) ◽  
pp. 117-125 ◽  
Author(s):  
Richard T. Houck
Keyword(s):  
North Sea ◽  
Seismic Data ◽  
Reflection Coefficients ◽  
Amplitude Variation ◽  
Data Set ◽  
Amplitude Variation With Offset ◽  
Full Characterization ◽  
The North ◽  
The North Sea

Lithologic interpretations of amplitude variation with offset (AVO) information are ambiguous both because different lithologies occupy overlapping ranges of elastic properties, and because angle‐dependent reflection coefficients estimated from seismic data are uncertain. This paper presents a method for quantifying and combining these two components of uncertainty to get a full characterization of the uncertainty associated with an AVO‐based lithologic interpretation. The result of this approach is a compilation of all the lithologies that are consistent with the observed AVO behavior, along with a probability of occurrence for each lithology. A 2‐D line from the North Sea illustrates how the method might be applied in practice. For any data set, the interaction between the geologic and measurement components of uncertainty may significantly affect the overall uncertainty in a lithologic interpretation.

scholarly journals Active Faulting in Lake Constance (Austria, Germany, Switzerland) Unraveled by Multi-Vintage Reflection Seismic Data

2021 ◽  
Vol 9 ◽  
Author(s):  
S.C. Fabbri ◽  
C. Affentranger ◽  
S. Krastel ◽  
K. Lindhorst ◽  
M. Wessels ◽  
...  
Keyword(s):  
Fault Zone ◽  
Seismic Data ◽  
Single Channel ◽  
Fault Zones ◽  
Lake Constance ◽  
Earthquake Catalog ◽  
Tectonic Structures ◽  
Reflection Seismic ◽  
The North ◽  
Major Fault

Probabilistic seismic hazard assessments are primarily based on instrumentally recorded and historically documented earthquakes. For the northern part of the European Alpine Arc, slow crustal deformation results in low earthquake recurrence rates and brings up the necessity to extend our perspective beyond the existing earthquake catalog. The overdeepened basin of Lake Constance (Austria, Germany, and Switzerland), located within the North-Alpine Molasse Basin, is investigated as an ideal (neo-) tectonic archive. The lake is surrounded by major tectonic structures and constrained via the North Alpine Front in the South, the Jura fold-and-thrust belt in the West, and the Hegau-Lake Constance Graben System in the North. Several fault zones reach Lake Constance such as the St. Gallen Fault Zone, a reactivated basement-rooted normal fault, active during several phases from the Permo-Carboniferous to the Mesozoic. To extend the catalog of potentially active fault zones, we compiled an extensive 445 km of multi-channel reflection seismic data in 2017, complementing a moderate-size GI-airgun survey from 2016. The two datasets reveal the complete overdeepened Quaternary trough and its sedimentary infill and the upper part of the Miocene Molasse bedrock. They additionally complement existing seismic vintages that investigated the mass-transport deposit chronology and Mesozoic fault structures. The compilation of 2D seismic data allowed investigating the seismic stratigraphy of the Quaternary infill and its underlying bedrock of Lake Constance, shaped by multiple glaciations. The 2D seismic sections revealed 154 fault indications in the Obersee Basin and 39 fault indications in the Untersee Basin. Their interpretative linkage results in 23 and five major fault planes, respectively. One of the major fault planes, traceable to Cenozoic bedrock, is associated with a prominent offset of the lake bottom on the multibeam bathymetric map. Across this area, high-resolution single channel data was acquired and a transect of five short cores was retrieved displaying significant sediment thickness changes across the seismically mapped fault trace with a surface-rupture related turbidite, all indicating repeated activity of a likely seismogenic strike-slip fault with a normal faulting component. We interpret this fault as northward continuation of the St. Gallen Fault Zone, previously described onshore on 3D seismic data.

Sign in / Sign up

Export Citation Format

Share Document