TGS Multi-Parameter FWI for Reliable Earth Properties

Home Case Studies TGS Multi-Parameter FWI for Reliable Earth Properties

TGS Multi-Parameter FWI simultaneously delivers direct estimates of subsurface velocity, reflectivity and their derivatives relative impedance and relative density.

location-pin

The Location

Location

Orphan Basin, Newfoundland and Labrador

Survey

Blomidon

Survey Year

2020

Survey Type

3D GeoStreamer

Configuration

16 streamers x 100 m x 8 km

Survey Size

3 526 sq. km

TGS has been acquiring modern 3D GeoStreamer data offshore Newfoundland and Labrador since 2015. The availability of such data has been a critical component in the success of the Call for Bids, from 2015 to present date. Access to 3D data provides confidence when bidding on prize blocks and the use of high-end technology shortens the time to first drill and potentially first oil. TGS holds the most comprehensive collection of subsurface data, including extensive 2D and 3D coverage in Eastern Canada. High-end imaging technology, like TGS Multi-Parameter FWI, and quantitative interpretation workflows clearly demonstrate significant prospectivity in the region, and particularly in the underexplored Orphan Basin.

MagnifyingGlass

The Challenge

Large-scale Paleogene marine fan systems

Large-scale Paleogene marine fan systems align along the shelf margin off the northeast coast of Newfoundland. The shallow water, multiples and velocity contrasts in the upper section are the main challenges for derisking the main lead (yellow ellipse). The uplift from TGS Multi-Parameter FWI improves the understanding of such prospects within the Blomidon survey. 

cs-challenge-image
light-bulb

The Solution

Data

Broadband 3D GeoStreamer

Processing

AVO/AVA compliant

Model Building

Reflection tomography and TGS Multi-Parameter FWI

Imaging

Kirchhoff and TGS Multi-Parameter FWI

Reservoir Characterization

Integrated quantitative interpretation

In a traditional sequential imaging workflow, velocity and reflectivity are inverted separately. Exploration teams must wait until the end of the data processing phase to be able to generate a density attribute from the data. TGS Multi-Parameter FWI implements Full Waveform Inversion (FWI) and Least Squares Migration (LSM) in a joint scheme and updates both velocity and reflectivity simultaneously at each iteration. It is a data-driven approach and can be run very quickly to deliver direct estimates of the subsurface velocity, reflectivity, relative impedance and relative density.

Reliable Structures, Balanced Amplitudes and Improved Reservoir Definition

Before Image After Image
RTM with Initial Model
TGS Multi-Parameter FWI
TGS Multi-Parameter FWI requires minimal pre-processing of the input data and can be run very quickly, enabling the technical teams to perform prospectivity and lead assessments ahead of exploration bidding rounds. Improved structural resolution, signal-to-noise ratio, suppressed multiples, and better reservoir definition provide confidence to the interpreters.

TGS Multi-Parameter FWI Delivers Better Event Continuity and Image Sharpness

Before Image After Image
Relative Impedance
Relative Density
Scroll left and right to view these relative impedance and density images (KPSTM on the left and TGS Multi-Parameter FWI on the right of each). They illustrate critical elastic parameters needed for reservoir understanding and the significant uplift of the simultaneous inversion. The left-hand-side of the relative density image (right) has been obtained by a comprehensive pre-stack simultaneous inversion using ultra-far stack angle stack whereas the density on the right-hand-side is an efficient by-product of the TGS Multi-Parameter FWI inversion. The improvements are clearly seen in terms of signal-to-noise ratio, seismic event continuity, and image sharpness.

Understanding Leads with a Robust Density Property

pgs-ultima-3d-density

Without TGS Multi-Parameter FWI it is difficult to produce a relative density attribute. Final and fully processed angle stacks with good signal-to-noise ratio are required. The pre-stack elastic inversion methodology normally used to predict density requires significant input and assumptions from geoscientists. This adds an extra layer of bias to the final deliverables. TGS Multi-Parameter FWI provides data-driven direct estimates of the subsurface velocity, reflectivity and their derivatives relative impedance and relative density. In enables technical teams to perform prospectivity and lead assessments with confidence.

Mitigating Exploration Risks Through an Improved Reservoir Assessment with TGS Multi-Parameter FWI

Before Image After Image
Relative Impedance
Relative Density
The left image is the relative impedance property extracted right at the reservoir interval. There are two potential reservoir features shown on the map. Both are notionally interpreted as marine fans. The primary target is shown with an orange outline. The second fan (yellow) is positioned further in the distal part of the map. Since it overlaps with the primary fan and widens the potential reservoir area it was necessary to assess it carefully for possible risks. An overlay of the density and the relative impedance is shown on the right. The secondary fan demonstrates a break in relative density, signaling a change in the reservoir property or a fluid change.
ChartBar-1

The Results

A Fast Data-driven Approach

TGS Multi-Parameter FWI is a good solution when time is critical, for example, if processing overlaps with a bid round schedule and puts exploration teams under pressure to meet deadlines. It is a fast data-driven approach that delivers direct estimates of the subsurface velocity, reflectivity, and their derivatives, e.g., relative impedance and relative density. Depending on the geological setting and the target level, it can start from minimal pre-processed input data and can be run very effectively, enabling the technical teams to perform prospectivity and risk assessments in a shorter time frame. 

Speak to Our Experts

Get in touch with a TGS representative today to book your demo and learn more about how TGS solutions can support your energy needs.

 

Talk to an expert

Have questions? Connect with our technical specialists to discuss your specific needs.

Schedule a consultation

Book a one-on-one session to explore how TGS solutions can support your projects.

Explore more

Visit our product pages and technical resources for deeper insights.