Earth Study 360 Technology overview
ES360 Components Full Azimuth Illumination EarthStudy 360 Imaging EarthStudy 360 Processor and Visualization Full Azimuth Anisotropic Tomography Full Azimuth Residual Moveouts Full Azimuth AVA Inversion Fastvel maybe included as well Components 2
Full Azimuth Decomposition and Imaging EarthStudy 360™ reflected ray incident ray g 1 2 REFLECTION DATA Half opening angle Opening Azimuth n 1 2 Dip of ray-pair inward normal Azimuth of ray-pair inward normal DIRECTIONAL DATA How do we solve the problem? (Transisitions Animation to Schematic – LAD, Schematic to polar angles – Direction of Propagation Animation – we decompose and image the seismic data using a rich ray tracing procedure based on a bottom-up exploding diffractor model that traces rays in all angles and all directions to achieve a uniform illumination of the subsurface. All arrivals are taken into account, all phases are preserved. Schematic – This ray trace procedure is used to map surface seismic data to subsurface image points. This mapping is performed in the LAD, a system for describing the interaction of the incidence and reflected wavefields where each wavefield can be decomposed into rays or beams indicating the direction of propagation. The direction of propagation of the incidence and scattered rays can be described in the polar angle domain with two independent systems of angles. Reflection Data (Scattered Data) – is defined by the opening angle (between incidence and reflected rays) and opening azimuth (orientation of the cross section between the two). The cone expands with increase in opening angle while the azimuth changes with direction. The directional data is defined by the zenith and orientation of the ray-pair inward normal (sum of I&R slowness vectors). Think of this as a mirror representing the orientation of the local reflecting surface. (The surface parameters for imaging include the X, Y, of S and R as well as the directional slowness vectors (Px, Py, Px. The subsurface parameters are defined by X, Y, Z of the image point and the four polar angles). A huge amount of data points, 4.2 billions, are required for representing the incident/reflected wavefield. This is the reason why the industry is using only few azimuthal sectors. As you will see through the next slides, our new invention enables to represent the same wavefield with much less data points, keeping optimal accuracy.
Two Types of 3D Image Angle Gathers Directional Dip and azimuth Reflection Opening angle and opening angle azimuth
Deliverables -ES360 Imager Directional Gather Specular Energy Weighted Stack – Final Image Diffraction Energy Weighted Stack – Fracture and small scale fault detection Dip and Azimuth Volumes for Tomography or Curvature Analysis Deliverables
Deliverables -ES360 Imager Reflection Gather Full Azimuth Angle Gathers used for kinematic and dynamic analysis Deliverables
Deliverables- AVAZ Full Azimuth AVA Inversion Isotropic Gradient and Anisotropic Gradient Volumes Fracture Density and Fracture Orientation Volumes Fastvel Delta2 and Fracture Orientation Volumes Deliverables
Deliverables HTI Inversion HTI Kinematic Inversion HTI Delta2 Map (fracture intensity map) HTI Axis of Symmetry Map (normal to the fracture plane) HTI Reliability Map Deliverables
Directional Angle Gathers Deliverables Focal mechanism able to discriminate between specular and diffraction waves Specular energy weighted stack Diffraction energy weighted stack Structural attributes dip, azimuth and continuity, directly from the directional angle gathers 9 Deliverables
EarthStudy 360 – Full Azimuth Directional Data Specular Stack Dip Azimuth Continuity FULL AZIMUTH DIP GATHER Deliverables
Depth Migrated Section from 3D Transition Area a) Directional angle decomposition followed by normal stack b) Image in the same area with specular energy weighted stack Deliverables
Diffraction Imaging Fractured Carbonate Reservoir in East Siberia The high resolution data is typically lost with traditional migration imaging kernels as they are biased towards the specular energy. Coherence is not based on wave propagation and acts on both types of energy. Scattered Energy Soft Taper Scattered Energy Hard Taper Migrated Slice 12 Deliverables
Reflection Angle Gathers Deliverables Full Azimuth Velocity Analysis - Tomography High Resolution Velocity Analysis - Tomography Kinematic HTI Inversion Reservoir characterization, fracture detection, and elastic parameters analysis/inversion (AVAZ) 1 Deliverables
Example of Residual Surface along ES360 Gathers- High resolution updates Automatic picking of delays on full azimuth angle gathers using the Poisson Picker multi azimuth acquisition the uncertainty in velocity determination is highly reduced Resolution of Small Velocity Anomalies by Wide Azimuth Reflection Data Tomography - Allon Bartana, Dan Kossloff Automatic picking of delays on 3D angle gathers -Allon Bartana, Dan Kossloff Deliverables
ES360 Reflection Gather – 2D Display ES360 Visualizer Gather panel colored by opening angle Gather panel colored by Azimuth Deliverables
Kinematic HTI Inversion Base carbonate carries classic signature of HTI anisotropy Deliverables
Kinematic HTI Inversion Kinematics: Reference : Effective Model for HTI / VTI Layered Media Zvi Koren*, Igor Ravve and Ronit Levy, Paradigm Geophysical Deliverables
Dynamic - Fracture Detection Deliverables We may consider to extract values along maps a) Normal Incidence b) Gradient c) Anisotropic Gradient a) Fracture Orientation b) Fracture Density Deliverables 18
Surface Sectors Multi -Azimuth How many sectors ? What is the correct azimuth sector ? Offset X Offset Y
Surface Sectors Multi -Azimuth How many sectors ? What azimuthal aperture ? What azimuthal aperture ? Offset X Offset Y
Azimuthal Discrepancy Map SEG Model
Benefit Fracture system detection High resolution Velocity Analysis Enhanced Specular Images Dense Ray Tracer Rich seismic information Uniform sub-surface illumination
Benefit Surface solution to a subsurface problem Multi – Azimuth requires a migration of each sector No HTI Inversion