Intelligent Interpretation: From Here to Where? Dr. Bradley Wallet

What is the Future for Seismic Interpreters? Dr. Bradley Wallet

Is it this?

Is it this? Belay that order!

Or, is it this?

Automatic horizon picking Widely accepted and available Relatively stable and mature technology Works with supervision

Automatic horizon picking +

Automatic horizon tracking

Automatic horizon picking

Significant steps forward Consistent dip (Petrel) – Provides consistent paths for horizon tracking using dip Sequence Stratigraphy Interpretation System (Opendtect) – Offers a fully automatic option for horizon tracking in a volume

Paleoscan

Paleoscan

Automatic fault extraction Wide spread availability Not widely used Reliability is highly variable Requires careful attribute tuning Requires careful qc Adding missing faults Removing spurious faults Combining fault patches

AFE in Petrel Edge Enhancement Seismic Conditioning Edge Detection Median Filter Dip Deviation Variance Original Seismic Structural Smoothing Gaussian Spatial filter Ant - Track Fault Volume Example Processes Thinning Chaos Bandpass filtering Edge Enhancement Seismic Conditioning Edge Detection Edit Extracted Faults Auto-track Interpretation Fault Interpretation (Visual Filtering) Post Conditioning Spatial Filtering Manual Interpretation Patches

Insight Earth

Geometric attributes: tools for 3D seismic stratigraphy 1. Introduction 0.0 1.5 t (s) convergent divergent Geometric attributes: tools for 3D seismic stratigraphy divergent convergent Calculation of reflector convergence and divergence is the first step toward 3D computer-aided seismic stratigraphy. In these images, positive convergence is shown as blue, and negative convergence (divergence) is shown as yellow. Like dip and azimuth, reflector convergence is a vector. Here, we display the component of convergence/divergence in the inline direction. After Barnes (2000b). (Barnes, 2002)

Towards computer-assisted seismic stratigraphy 1. Introduction Towards computer-assisted seismic stratigraphy moderate amplitude continuous high amplitude continuous low amplitude continuous moderate amplitude semicontinuous high amplitude semicontinuous low amplitude semicontinuous transparent A typical seismic facies classification using an interpreter-trained probabilistic neural network, in which multiple facies classes have been identified. The seismic classification scheme on the right consists of high-amplitude (HA), moderate-amplitude (MA), low-amplitude (LA), continuous (C), and semicontinuous (SC) seismic facies. After West et al. (2002). 4. Generate a seismic facies map 2. Choose attributes that differentiate these zones 3. Train a neural network to imitate an interpreter Select zones of geologic interest for training (West et al., 2002)

Towards computer-assisted 3D seismic stratigraphy 1. Introduction Towards computer-assisted 3D seismic stratigraphy coherence 3D seismic facies Geologic Interpretation (a) A coherence slice highlighting the lateral edges of a channel (red lines), a broad, older sinuous element (1), and a narrower, younger sinuous element (2). (b) A seismic facies slice, showing that sinuous element (1) is composed of high-amplitude-continuous (HAC) to moderate-amplitude semicontinuous (MASC) seismic facies, whereas sinuous element 2 is composed primarily of HAC seismic facies. Because the texture-analysis seismic-facies classification is a volume, this type of analysis can be applied at different stratigraphic levels within an interval of interest, whether or not the interval is bounded by mapped horizons. (c) Considering the conceptual relationships between seismic facies and their potential associated geologic fill, the net-to-gross environment can be understood and 3D regions can delineate differing depositional and geologic properties. After West et al. (2002). (West et al., 2002)

Unsupervised learning (clustering) 1.8 N 2D histogram 5 km Time (s) SOM latent axis 2 2.1 Similarity 0.3 1 100% Opacity (b) 1.7 (a) SOM latent axis 1 Time (s) 2D colorbar (b) 2.0 SOM latent axis 2 (d) 1.7 Amplitude − + 100% Opacity (c) Time (s) SOM latent axis 1 (c) 2.0 1.8 (e) (d) (f) Time (s) Because seismic is the only data we have, we want to look for evidence for the previous interpretation on vertical seismic amplitude sections. Section A shows the northern channel complex. We use red line to outline the channels. In this vertical section, Horizon A is at the middle of the SOM facies window. We can find channels are mapped in cyan to purple colors, while the surrounding overbank complex deposits mapped in yellow to brown colors. In section B, we can see the lateral migration of this channel complex. Here are at least four channel stories migrating from northeast to southwest. We can also see the oldest story is mapped as lime green, while the younger channels are cyan. This suggests a change in grain size during deposition. The oldest story is sand-filled, and the younger stories are mud-filled. The more distal part of this channel is more spread out, forming a lobe mixed with the other main channel. We also see an oxbow-like feature in the older deposits. At last, for the two twisted channels, we can clearly see the red channel cutting through the older sand-filled channel in lime green. Similar to the northern main channel, we see the width of these two channels has expanded dramatically from proximal to distal, merging into a lobate feature. Inline 2.1 Z-scale=1:5 Crossline (e) (f) 1.7 1.7 Time (s) Time (s) 2.0 Horizon A 2.0

Where are we? Focused on individual data sets Crafted and user intensive Extends the efficiency of the interpreter Dependent upon the skill of the interpreter Allows the interpreter to quickly interpret in 3D

How far can we go? Multi-data set learning is possible Object based learning is on the horizon Completely map the facies in the data set

What’s probably too far? Computer can interpret the seismic Human will still need to interpret the interpretation

Let us hope Belay that order!

But… We are increasingly removing the geophysics from interpretation of seismic. At this point, will a geologist be more qualified to do the interpretation than a geophysicist?

This could be possible…