The Satellite Mapping Blog

52 years...Happy anniversary to us!

The Satellite Mapping Team — Mon, 30 Sep 2024 08:20:08 GMT

At Viridien Satellite Mapping we have a long heritage of developing cutting-edge satellite remote sensing-derived solutions across a huge range of markets.

For over 50 years, we’ve been delivering valuable data and insights to our clients making us one of, if not the longest-established private satellite remote-sensing company in the world.

Over that time, we have evolved into a variety of specialist teams, spanning a wide range of markets, capabilities, and solutions. Our long heritage directly correlates to our expertise in remote sensing data processing. If there is an EO data set out there, you can be certain we have played with it and found suitable and unsuitable applications for it. By partnering with us, you benefit from that expertise and knowledge base without having to take on the trial-and-error risk yourself.

Who are our teams?

Imagery and Data Services (IDS) team: Focused on building bespoke remote sensing solutions and providing imagery from the global Earth Observation marketplace (open access and commercial) for internal and external clients. The team handles R&D projects that push the boundary of what is possible with Earth Observation data for some of the largest energy and resource companies in the world. We have reseller agreements with a broad array of satellite operators offering optical, elevation, multi/hyper-spectral and Synthetic Aperture Radar (SAR) datasets so that we can offer you the best data for your project. We can either provide this data directly to you, sometimes at discounted rates due to our reseller status, or we can complete our own value-add processing to help you get more actionable insights from the imagery, quicker.

InSAR team: Our dedicated InSAR teams produce high precision (mm/year), ground and structure displacement datasets from across the Earth. Our InSAR provision offers the full spectrum of scopes the technology and market allow. Spanning markets such as Mining, Oil and Gas, CCS, Geothermal, Natural Hazards (e.g. Volcanoes, Earthquakes, Landslides and Sinkholes), Infrastructure Structural Health Monitoring (Tunnelling, bridges, dams, slopes) and forensic analysis services for Insurance and legal cases. Our InSAR team has existed for over 30 years, matching the birth of the first SAR satellite for monitoring the Earth's land surface, ERS-1 in 1991. This makes our InSAR team one of the oldest, if not the oldest commercial satellite InSAR team in the world. With all the years of experience providing InSAR to our customers, we have developed our own optimized algorithms and workflows for specific applications to help us generate the highest precision, most reliable data and reports for our clients. A key element in guaranteeing our customers get the most out of InSAR data which we have learnt over these many years is to provide a “one-team” approach to projects with our clients. Only through strong collaboration and dialogue between end-users and our InSAR experts can we give you the best ground displacement solution for your needs and for you to get the support you need to easily make sense of the data and use it to make informed decisions.

Offshore exploration and environment teams: We have been identifying and mapping natural oil seepage slicks (for use as an oil and gas exploration tool and to de-risk proposed offshore CCS projects) and pollution slicks (for regulatory or forensic pollution monitoring) for several decades. Our slicks database is unique, global, and ever-growing as new imagery is collected and interpreted. We’ve even partnered with companies seeking out sunk and lost vessels including WW2 battleships! We apply the same satellite and processing technologies to SeaScope, which proactively monitors offshore pollution across individual facilities to entire corporate portfolios, supporting our clients with compliance commitments and sustainability goals, and early warning of potential spill events.

Geology team: Focused on generating exceptional satellite-based geological and mineralogical interpretations and models, plus structural cross-sections of the Earth from continent to outcrop scale. These provide vital insight and value during early exploration for energy and mineral exploration. Their latest achievement is our BareEarth+ datasets which are derived from specialized processing of entire archives of satellite imagery. This is an enormous achievement and something only attainable by companies with extraordinary computing power and highly specialized remote sensing and geology experts, such as Viridien. This moonshot product is just the beginning, but is already making waves with our clients in the energy and resource exploration space.

Innovation team: Made up of data scientists and developers to propel our IT infrastructure, architecture, data science, ML/AI, workflows and analysis tools into the future for the production teams. They enable us to play with all the open-source and commercially available data we can get our hands on and run it through our workflows at pace and scale. Powered by Viridien’s world-leading High Powered Computers (HPC), we can perform complex analysis on the biggest EO datasets, at industry-leading speeds.

The support of Viridien and all its support functions, ~40 global offices and 3500+ employees including the AI lab, Geotechnical Engineers, Minerals & Mining team, Geology team, Multiphysics group, Instrumentation and all the experts and Geoscientists who give our data greater contextual meaning and our clients the solutions they need.

We are inspired by how far we’ve come in the past 50+ years and are excited to see what the future holds! If you think Viridien Satellite mapping can benefit your business, please get in touch - satellite.info@Viridiengroup.com

SatExplorer: doing the heavy lifting in EO data delivery, visualization, and analysis

Duncan Witts — Thu, 18 Jul 2024 02:12:33 GMT

We’re very excited to formally release SatExplorer - VIRIDIEN (formerly CGG) Satellite Mapping’s web-based platform to deliver, visualize, and analyze data from VIRIDIEN Satellite Mapping.

It’s nothing new that Earth Observation datasets are becoming exponentially larger. It's also not new that gaining valuable intelligence and information from these datasets is becoming a bigger challenge. Compounding these challenges, the beneficiaries and end-users are often not Earth Observation scientists or data scientists. In almost all cases, end-users want an intuitive, accurate, and secure solution to quickly gain insights from these datasets. SatExplorer has been developed to address these challenges and desires of our customers. SatExplorer is the vehicle to help our carefully and expertly handled data benefit our customers. The vehicle is important, but clients want this with the reassurance that the data and tools being served to them via SatExplorer are of the highest industry standards.

The Satellite Mapping team at VIRIDIEN was formed over 50 years ago and has been leading the commercial use of satellite remote sensing data in a variety of industries ever since. Our highly experienced Earth Observation data specialists have worked closely with clients in those industries and taken on their feedback to ensure SatExplorer doesn’t just address their objectives and pain points, but fulfils them.

To cope with the ever-increasing size of EO datasets and the computer processing required to make sense of it all, VIRIDIEN is uniquely placed amongst our competitors. We have access to the supercomputing, AI-data-crunching powerhouse of VIRIDIEN's High Powered Computing (HPC) with over 500 petaFLOPS of computing power – that’s over 500 quadrillion floating-point operations per second. Or in an Earth Observation sense, it allows us to make and iterate through stacks of 1000's of interferograms in seconds not days, or process the entire archive of ASTER multispectral data to produce the barest Earth mosaic possible: VIRIDIEN’s BareEarth+. This frees up our Remote Sensing experts' time to build reports and deliverables that are even more catered to specific end-user requirements derived from datasets only VIRIDIEN can produce.

SatExplorer can incorporate the full range of VIRIDIEN Satellite mapping EO and EO-derived datasets including InSAR data. In this case, gaining ground displacement insights is a major requirement facing engineers and other end users interested in monitoring the performance of engineered assets. This is to identify areas that may require intervention before hazards emerge. VIRIDIEN’s SatExlorer and InSAR data are a perfect combination for asset stakeholders interested in risk management of structures such as Tailings Storage Facilities (TSFs) seen in the screenshot below. Here, the Engineer of Record (EOR) and the Responsible Tailings Facility Engineer (RTFE) can both access the same monitoring data, quickly identify the spatial distribution of ground displacement, and interrogate the time series of movement behind each pixel. Not only does this provide them with many magnitudes more monitoring measurements, but SatExplorer gives them the intuitive tools to make sense of this vast data set and identify, for example, where ground displacement is accelerating ahead of a potential slope failure.

SatExplorer is cloud-hosted for faster access and removing the headache of downloading data before you can gain value from it. Geotechnical professionals and other stakeholders only need their login and an internet connection to visualize, filter, analyze, and download their data.

For asset owners requiring portfolio monitoring, SatExplorer can provide you with customised dashboards highlighting specific data across all of your sites in one place. We are experienced in building and visualizing data sets so that we can highlight the information that matters most to you. And if what matters to you changes, we will change your data in SatExplorer with you so that the data you buy is always as actionable as we can make it.

SatExplorer supports direct integration with GIS applications. We are so committed to making sure our data delivers maximum impact, that our data can seamlessly be fed into your GIS applications to complement your existing workflows and reporting. Or indeed, if you are looking for a monitoring data integration solution that incorporates all your ground-based instrumentation and EO-derived data sets, VIRIDIEN’s all-encompassing geotechnical monitoring solution is iSiteCentral. You can read more about that and enquire on our website.

But if it’s Satellite Mapping data that you want to visualize and analyze quickly, precisely and at scale, look no further than SatExplorer from VIRIDIEN.

Our hope is to continue to work closely with our clients to make sure SatExplorer and our data sets are providing solutions to their objectives, requirements, and pain points. We will continue to seek out feedback and to further develop our products and services to maximize the successes that can be reached by us and our customers, together.

A new cover, still highly specialized

The Satellite Mapping Team — Mon, 10 Jun 2024 13:47:59 GMT

On the 16th May, CGG announced to the world that we are changing our name to Viridien. We have been CGG or similar for over 90 years so this is pretty big news. But today is the day we officially launch our new brand.

Viridien, (www.viridiengroup.com), is an advanced technology, digital and Earth data company that pushes the boundaries of science for a more prosperous and sustainable future. With our ingenuity, drive and deep curiosity we discover new insights, innovations, and solutions that efficiently and responsibly resolve complex natural resource, digital, energy transition and infrastructure challenges.

Sophie Zurquiyah, CEO, Viridien, said: “Our new name, Viridien, connects our company’s history to our future, confidently positioning us for accelerated growth as an Advanced Technology, Digital and Earth Data Company.”

At Satellite Mapping, we’ve also gone by many names over our 50 year heritage such as NPA, Fugro NPA, CGG and now Viridien. But we remain the same team, dedicated to delivering high-quality work! CGG’s rebrand to Viridien will provide Satellite Mapping with greater visibility and allow us to grow and expand in our current and prospective markets.

These are exciting times. We are Viridien.

Resolution evolution: Newly launched and upcoming notable Earth observation news

The Satellite Mapping Team — Fri, 03 May 2024 05:10:36 GMT

In the rapidly advancing landscape of satellite technology, prominent players are consistently achieving remarkable milestones by expanding their constellations to not only provide higher revisits, but to ensure extraordinary resolution capabilities.

Maxar's WorldView Satellite Constellation is poised to make a great leap forward with WorldView Legion which will provide 29cm high-resolution satellite imagery with an impressive revisit rate of 15 times per day. The constellation will consist of six satellites, each equipped with nine spectral bands. Congratulations to Maxar on the launch of the first WorldView Legion satellites via SpaceX yesterday on 2nd May 2024.

Capella Space will continue to launch more of their next-generation Acadia SAR satellites during 2024, including Capella 14 which launched on April 7th 2024. These new satellites deliver increased image resolution, quality, power and bandwidth [now at 700 MHz], and reduced data downlink latency and delivery lead-times via a fully automated platform.

Another operator aiming to achieve the top capability in 2024 is Satrec Initiative Imaging Services (SIIS). SpaceEye-T, scheduled for launch next year, is set to contribute with its five-band imaging capability. Boasting a spatial resolution of 0.3 m in its panchromatic band and 1.2 m in its multispectral bands, SpaceEye-T promises a swath width of 14 km, bringing advanced imaging capabilities to low Earth orbit. SpaceEye-T not only secures SIIS's entry into the optical 30cm imagery club alongside Airbus, Maxar, and ImageSat International, but also lays the groundwork for the expansion into a constellation of high-resolution imaging satellites owned by the company.

Integrating higher resolution and quality data into CGG’s current services enables us to provide more accurate products to our clients across multiple industries. With this enhanced resolution and increased revisit time, DEM (Digital Elevation Model) generation becomes more frequent and more accurate, facilitating better understanding of infrastructure development and terrain analysis within our MineWatch service. Additionally, improvements in data delivery lead times are particularly important for CGG’s monitoring activities.

CGG’s status as an independent supplier for satellite operators around the globe guarantees comprehensive and impartial advice, every time. Get in touch with our team to discuss how satellite imagery can support your project.

Bring on the hype!

Duncan Witts — Tue, 30 Jan 2024 14:11:41 GMT

A new year, and a new array, with 2024 set to deliver several exciting hyperspectral satellite platforms that will further expand our capabilities in Earth Observation.

Pixxel sits at the forefront of the world's venture into spaceborne hyperspectral earth imaging satellites, all geared towards extracting valuable insights and building a health monitor for the planet. Already turning heads in the industry, Pixxel has successfully launched three satellites, a beta version of Aurora - their geospatial analytics platform - and collaborated closely with a global network of resellers and partners to expand their footprint. With six hyperspectral satellites with a 5 m spatial resolution (the world’s highest resolution so far) scheduled for launch in 2024, Pixxel's constellation is poised to achieve daily global coverage.

Why the hype? Hyperspectral imagery enables the detection, monitoring, and prediction of various global phenomena, supporting effective decision-making across a multitude of applications, including agriculture, mining, environment, and energy use cases. The versatility of hyperspectral technologies is evident in their diverse nature across different sectors, providing critical data for accurate analysis and response through a multitude of wavelengths. With high spectral resolution hyperspectral imagery, Pixxel is ushering in this new era of satellite technology, and we eagerly anticipate the upcoming launches in 2024.

Hamersley Australia Ore exploration and mineralogy mapping. Imagery courtesy of Pixxel, 2024

Sticking with the hyperspectral theme, Orbital Sidekick (OSK) is gearing up for an extensive expansion of its GHOSt constellation during early 2024, enhancing persistent monitoring capabilities that ensure operational integrity for organizations worldwide. Designed for swift insights, the GHOSt constellation utilizes onboard analysis to screen for unique chemical fingerprints, all whilst in orbit. This information is then beamed to Earth for direct customer reporting or enhanced analysis, highlighting features of interest such as mineral hotspots or methane concentrations. The GHOSt constellation signifies a substantial advancement in OSK's sensing capabilities, enabling the company to scale its commercial product with larger coverage and reduced revisit times with the world’s leading spatial resolution for such advanced hyperspectral capability. Alongside the two additional satellites being launched in 2024, OSK is thinking big, with plans to further expand the constellation to 14 satellites during 2026.

The CGG Satellite Mapping team is already incorporating hyperspectral satellite data into several of our workflows, but most notably our mineral exploration work. The hyperspectral data complements our Bare Earth+ product beautifully, providing our clients with richer insight into mineral systems, and greater efficiency and confidence in identifying targets for further exploration.

It’s pretty clear that spaceborne hyperspectral is ever evolving with further innovation and launches coming this year by Xplore, Kuva Space, Planet, and more. Is the immediate future of remote sensing here? Hyperspectral certainly seems to be redefining remote sensing possibilities. Watch (this) space!

A significant leap forward for spaceborne thermal data

The Satellite Mapping Team — Thu, 28 Sep 2023 12:47:16 GMT

CGG Satellite Mapping is proud to announce a groundbreaking addition to our repertoire – we are now official resellers of SatVu’s HOTSAT-1 thermal data.

This marks a pivotal moment in our journey, as we bring the first commercial high-resolution spaceborne thermal sensor to your fingertips. With this exciting development, we aim to empower our clients to harness the power of thermal data across various sectors, including environmental, industrial and energy, on a global scale.

Launched in June 2023, HOTSAT-1 brings revolutionary high resolution mid wave infrared data to the market. This cutting-edge sensor is designed to measure industrial thermal emissions from industry, shedding light on energy waste and driving improvements during the energy transition movement. With its video capabilities also enabling highly dynamic feature detection, its applications extend far beyond.

Key features of HOTSAT-1:

· Spatial resolution: 3.5m

· Swath: 3.5 X 4.4 km

· Spectral channels:

MWIR: 3700 – 4950nm (Night Mode), MWIR: 4500 – 4950nm (Day Mode)

· Video Capabilities

· Thermal sensitivity: < 2°

· Dynamic range (at acquisition): 16-bit

The addition of SatVu’s HOTSAT-1 thermal data to our offerings at CGG Satellite Mapping represents a significant leap in the world of remote sensing and data analytics.

Come and talk to CGG today to understand how Sat Vu’s data can be incorporated into your project.

Figure 1: HOTSAT-1 Heat Loss insights London,UK, © Satellite Vu

Figure 2: Street and building-level thermal data from satellite, ©Satellite Vu

All images Credit: Satellite Vu

Dam Safeguarding from the Sky: Enhancing Infrastructure Management with Satellite InSAR

The Satellite Mapping Team — Fri, 08 Sep 2023 09:55:42 GMT

As the longest running commercial provider of InSAR, CGG have delivered solutions to a wide variety of sectors. Of these, the infrastructure and engineering sector has presented some of our most interesting studies. The application of InSAR can lead to improved safety, more efficient resource allocation, better planning and design practices, and enhanced decision-making processes. Here, we demonstrate InSAR’s ability to monitor and support the development and management of a critical infrastructure project.

Critical infrastructure plays an integral role in society today. As we shift toward a more sustainable future, it is vital that regular monitoring is undertaken to ensure the safety and integrity of these structures. CGG’s satellite deformation detection, backed by high-power computing, provides rapid insights into the status of an asset with millimetric precision.

Water dams enable the control and distribution of water supplies, in addition to carbon offsetting through hydroelectric power generation. However, the often isolated and inaccessible locations of dams mean that ground-based investigation techniques can be extremely difficult and potentially dangerous to implement. CGG’s satellite-derived deformation monitoring, known as InSAR, provides an accurate and remote solution to detect short- and long-term displacement anomalies, aiding risk management.

Figure 1 - Thisavros Dam, Greece. © Esri, DigitalGlobe, GeoEye, Earthstar Geographics, CNES/Airbus DS, USGS, AeroGRID, IGN, and the GIS User Community.

The Thisavros Dam, on the Nestos River in north-eastern Greece, is a 172m high rock-fill dam - the tallest of its kind in Greece. The structure supplies hydroelectric power and irrigation solutions to the local area. The dam’s location is close to the border with Bulgaria, in a seismically active region characterized by rugged, mountainous terrain, complex, highly faulted, and sheared geology and complicated hydrogeological conditions. Consequently, dam construction and stabilization were extremely challenging (Anastassopoulos et al., 2004), and two large landslides that occurred during construction required significant, time-consuming remedial measures and major adjustments to the project design. Construction at the site lasted for 10 years, ending in 1996 with the commencement of reservoir filling. More than a decade after completion, another major failure occurred at the right abutment of the dam where a broad shear zone intersects a steep slope of hydrothermally altered and weathered rock mass (Loupasakis et al., 2011).

Thisavros is a good candidate for InSAR analysis for several reasons. Firstly, the man-made embankment acts as a reflective surface to consistently reflect radar waves back to the satellite. Secondly, surface conditions do not change on the embankment and the size of the dam is easily resolvable in open-access Sentinel-1 radar images. Finally, the age of the dam allows a long-term study of deformation to be undertaken. These advantages are common across many large infrastructure projects, making InSAR an effective and valuable tool in monitoring the built environment.

CGG utilised Sentinel-1 SAR imagery (~20 m spatial resolution) spanning 5 years to derive the long-term deformation trends, including seasonal variations. Displacement was determined from January 2018 to February 2023 using both the ascending and descending lines of sight (LOS). By considering the radar's viewing angle, incidence angle, and satellite geometry, it is possible to calculate the vertical and east-west horizontal components of deformation using trigonometric relationships.

Displacement results are shown below. There is a clear vertical subsidence trend of up to -5 mm/yr across the dam, decreasing away from the centre. A consistent trend is observed in the horizontal result, where displacement is orientated towards the centre of the subsidence bowl.

Figure 2 - Vertical and horizontal displacement of Thisavros Dam. Vertical time series is inset and extracted from area within the blue circle [left]. Arrows indicate direction of horizontal displacement [right]. © Contains modified Copernicus Sentinel data 2023.

Displacement maps serve as a valuable tool to gain comprehensive insights into the spatial patterns of displacement. However, conducting time series analysis is equally important. Here, the CGG Satellite Mapping ArcPro toolbox was utilised. Not only does the time series in Figure 2 depict the long-term subsidence pattern indicated by the displacement rate maps, but it also reveals a short-term seasonal variation.

Seasonal deformation trends can occur for several reasons, e.g., fluctuations in soil moisture, groundwater extraction, thermal expansion, freeze-thaw cycles. Figure 3 shows a time lapse of radar images across the reservoir over the 5-year study period. The level of the lake varies significantly, peaking in the summer and reaching a minimum in the winter. The surface area of the reservoir was calculated from the radar images and plotted as a function of time in Figure 4.

Figure 3 - Time lapse of radar images showing rise and fall of the upstream reservoir. Dam is top right of image. © Copernicus Sentinel data 2023.

Once the linear subsidence trend is removed from the vertical deformation record, Figure 4 shows an antiphase correlation between the lake surface area and vertical deformation. It is likely that high water levels during the summer exert greater pressure on the dam, causing it to subside. When the pressure is relieved in the winter, the dam rebounds.

Figure 4 – Vertical deformation and lake surface area plotted as a function of time. Arrows demonstrate antiphase.

A consistent trend is shown in the horizontal results (Figure 5). In this case, the long-term trend is movement towards the centre of the dam (i.e., area of greatest subsidence). However, on average, the entire dam is moving to the east at a rate of ~1 mm/yr. In the short term, the entire dam moves towards the east (i.e., downstream) in summer and towards the west (upstream) in winter.

Figure 5 – Horizontal deformation and lake surface area plotted as a function of time.

These seasonal variations in the reservoir level are causing the dam to flex downstream (subsidence + eastward horizontal movement) in the summer and rebound in the winter. This short-term deformation pattern is superimposed on a slower, linear long-term trend of movement downstream.

In an operational monitoring context, these measured displacements would be interpreted in the context of the expected behaviour of the structure. Dams are typically designed to accommodate an amount of displacement during normal operational conditions. InSAR measurements can be compared to the anticipated behaviour to confirm that this remains within safe limits, or where these have been exceeded prompt further investigations or mitigations.

CGG's InSAR measurements can be combined with Geocomp's ground-based assessment services to provide an integrated, comprehensive monitoring solution. To find out more, please contact the Satellite Mapping Team.

References:

Anastassopoulos, K., Hoek, E., Milligan, V., Riemer, W., 2004. Thissavros hydropower plant managing geotechnical problems in the construction. Proceedings, Fifth International Conference on Case Histories in Geotechnical Engineering, NY, April 13-17, 2004

Loupasakis, C., Rozos, D., Georgakopoulos, A., 2011. Remedial Measures for the Restoration of an Extensive Rock Slope Failure at the Right Abutment of the Thisavros Dam, Nestos River, Greece. Proceedings, Slope Stability 2011: International Symposium on Rock Slope Stability in Open Pit Mining and Civil Engineering, Vancouver, Canada (September 18-21, 2011)

Context is everything: Hyperspectral data over the Egyptian Eastern Desert

Duncan Witts — Tue, 15 Aug 2023 13:52:56 GMT

The Eastern Desert of Egypt is a highly prospective region for mineral exploration, and with the 2023 Gold and Associated Minerals bid round well underway, it is the perfect timely playground for remote sensing. The image below shows some initial basic outputs from imagery acquired by the EMIT hyperspectral sensor, currently hitching a ride on the ISS. They clearly demonstrate the insight we can begin to glean from satellite hyperspectral data, and this is before we even look at high spatial resolution imagery and elevation data.

Identifying representative endmember pixels, and analyzing their spectral curves gives insights into the geological processes they represent. Unmixing these endmembers to find the corresponding abundance maps shows the distribution of these processes across the Earth’s surface. However, before we get ahead of ourselves and start disregarding geological maps and pointing the finger at endmembers, it is important to understand the limitations and uncertainties that come with this remote sensing technique.

In the above example, three endmembers representing the most disparate spectral signatures were selected. The red band highlights compositionally mature material, likely representing extensive chemical weathering and the production of quartz-rich material, such as terrestrial sand cover. The green band highlights clays such as illite and muscovite which form in a range of environments from various geological processes. It will also cause some slight response in Mg-OH bearing minerals and carbonates, and this must all be considered during interpretation. The blue band preferentially highlights carbonates such as calcite, but also causes some response in Mg-OH bearing minerals such as actinolite. Given that many of these endmembers may show degrees of responses across different bands, and may result from lithological or alteration processes, interpretation is far from a trivial ‘point the finger’ exercise. In addition, having spectral information from 285 bands that EMIT provides, it is impossible to represent the full high dimensionality of these data in three color channels alone, and far more distinctions can be made than are observed in the image.

We also need to consider the size of the pixels we are dealing with – in this EMIT case they equate to approximately 60m X 60m on the ground. That’s quite a large area – just shy of 14 tessellated tennis courts – and so you can imagine there will be quite a mixture of geological (and possibly non-geological) bits and pieces within a single pixel. We can go some way to ‘un-mix’ the jumble of spectra, but unmixing will not just depend on the endmember we’re wanting to display, but also how similar the other endmembers are. What we can say with some degree of certainty, is that some spectral absorption features observed across a given pixel show a statistically closer resemblance to say, clay minerals than fe-oxides, for example, and which of these are more dominant than others. We can also start to analyze specific characteristics of the absorption features which allow us to begin distinguishing one clay mineral, such as illite, from another, thanks to the sensitivity of hyperspectral data. What we can’t determine, particularly at this Grand Slam resolution is which of the 14 tennis courts contain the 'probable illite'.

This may seem to be taking some of the prettiness out of the spectral mapping picture, but it is not intended to. Spectral mapping is a highly effective and valuable tool in the mineral exploration toolkit, but all too often we see maps of spectral outputs being presented that definitively assign specific minerals to a given pixel. Yes, a pixel may contain illite, but it may not. Or it may contain an assemblage of clay minerals that might include illite in some proportion.

To begin reducing these inherent uncertainties and unwanted noise, we need geological context. This is vital, and unless you have expansive field data, geological maps should be the first port of call. These provide a lithological and structural backdrop to the spectral outputs and will assist a geologically sensible interpretation. However, scale and reliability are key. The value gained from aligning hyperspectral results (even those with a coarse spatial resolution) against a regional 1:1 million scale geological map, is limited; and assuming published geological maps are accurate and correct can be disastrous. As such, having the ability to generate an accurate, detailed structural framework and lithological setting at the appropriate scale is invaluable, and in our opinion should be an integral part of any spectral mapping project. In the Egypt example shown above, we will typically generate a 1:25,000 scale geological interpretation from a combination of satellite optical, radar and elevation data, supported by published geological maps, reports and any geophysics and/or field data that may be available. When integrated with the spectral results, it enables us to take more confident steps towards the pointy end of the mineral exploration process. Target areas can begin to be ringfenced for follow-on work, such as 1:5,000 scale multispectral and structural mapping. We can do this too, using optical imagery sharp enough to distinguish compositional variability in sub-meter wide dykes, and focus boots on the ground fieldwork.

Egypt is just one of a multitude of prospective geographies we are currently working on, supporting our clients with honest expertise, from project concept to delivery. If you'd like to know more about what we are up to, drop us a line.

New-Found Seepage

The Satellite Mapping Team — Mon, 15 May 2023 12:24:01 GMT

The Seep Hunting Team at CGG Satellite Mapping have undertaken a detailed study of the archive of satellite SAR (Synthetic Aperture Radar) data and multispectral optical imagery offshore Newfoundland, covering the Mesozoic St. Anthony, Orphan, and circum-Grand Banks sedimentary basins. This study not only includes the site of the current NL-23 licensing round, but also bp's high impact Ephesus well that was spud last week. Given the vast area on offer and the frontier nature of the region, offshore oil seepage hunting remains an excellent method for establishing petroleum system existence.

This animation shows temporally repeating seepage slicks observed offshore Newfoundland. The close spatial repetition in deep water (3 km), paired occurrences, and curved nature are indicative of natural oil seepage; all the more interesting as these slicks are located more than 400 km from the current discoveries.

The key to unlocking the slick distribution across this area was targeting weather compliant scenes acquired in the summer months when variations in met ocean conditions lead to increased seepage activity, albeit these events are transient in nature. We utilize a unique detection technique that involves advanced processing and expert interpretation of Earth Observation (EO) data that enables confident identification and categorization of slicks on the ocean surface.

Paired seepage slicks drifting against the natural film in the region. Image © CGG, Contains modified Copernicus Sentinel data, 2022.

For more information on this site and the rest of our Canada dataset and its key deliverables, please get in touch with our Seep Hunting Team.

Email: satellite.info@cgg.com
Telephone: +44 (0)1732 865023
Website: www.cgg.com/satellite
LinkedIn: CGG Satellite Mapping
Twitter: @CGGsatellite

InSAR and Icelandic Eruptions

Duncan Witts — Wed, 01 Mar 2023 13:31:18 GMT

After near 800 years of quiescence, the Fagradalsfjall volcano in Geldingadalur erupted in March 2021 and volcanic activity persisted for six months. Following weeks of moderate seismic activity on the Reykjanes Peninsula, including four earthquakes in excess of 4.5 M_w, another period of volcanism commenced on August 3^rd, 2022. A 360 m long narrow fissure opened in the Meradalir Valley, ~1 km away from the site of the 2021 eruption. Lava was initially emitted at a rate of up to 32 m³ s^-1, decreasing to 2 m³s^-1 over the subsequent 2 weeks.

This article presents some excellent work recently completed by Amy Lloyd and Ben Conway-Jones from the Satellite Mapping InSAR team, showcasing the value of utilizing InSAR within a geological context to better understand the character of natural phenomenon of this type.

2022 eruption

Analysis of the 2021 eruption by the CGG Satellite Mapping group demonstrated the suitability of InSAR in quantifying the magnitude, spatial extent, and temporal evolution of this type of natural phenomenon. A similar approach was undertaken to characterize the 2022 eruption and compare it to the 2021 event.

Figure 1 is an interferogram illustrating the phase difference between radar images taken either side of the eruption on 30/07/2022 and 23/08/2022. Images were taken from the descending (i.e., north to south) line of sight (LOS). Each rainbow stripe, known as a fringe, represents a change in distance of one phase (or π multiplied by the radar wavelength) between the surface and the satellite. Towards the earthquake epicenter, these contours become increasingly condensed, illustrating a significant degree of deformation.

Figure 1– Interferogram of Reykjanes Peninsula from Descending LOS. Phase difference between 30/07/2022 and 23/08/2022.

In order to determine the vertical and horizontal components of deformation over a long period of time, measurements were taken from both ascending and descending LOS over several months. Figures 2 and 3 show horizontal and vertical deformation of the Reykjanes Peninsula between April and October 2022.

Deformation over this period was dominated by signals centered on the Meradalir Valley, consistent with surface volcanism. The horizontal result shows movement along an ENE-WSW striking fault. The northern fault block is moving west, whilst the southern block is moving east. This tectonic movement is consistent with the mid-Atlantic spreading ridge that bisects the island, as the North American and Eurasian plates diverge.

Figure 2 – Horizontal displacement map of Reykjanes Peninsula between April and October 2022.

Figure 3 - Vertical displacement map of Reykjanes Peninsula between April and October 2022.

Since the fault is broadly strike slip, vertical deformation is not directly associated with tectonism. Instead, this more complex pattern is characteristic of dyke intrusion. Upward propagation of magma generates a net uplift signal. However, a trough of subsidence, known as a graben, is observed directly above the dyke.

Overall, this deformation signal is remarkably similar to the 2021 event. Horizontal deformation occurred in broadly the same orientation and is focused on the same fault segment (proximal to the Fagradalsfjall volcano). Notwithstanding, the magnitude and spatial extent is reduced.

The consistency of vertical deformation between the 2021 and 2022 events suggests the magmatic system is unchanged. This inference concurs with the finding that basaltic lava compositions between the two eruptions are nearly identical.

Tracking lava flow using InSAR

In many ways, the Reykjanes Peninsula is an ideal location for InSAR analysis. Rough, rocky ground provides strong consistent backscatter of incoming radar signals. Deformation is often substantial in both amplitude and spatial extent. Elevation changes are moderate and do not obstruct radar signals. However, in some cases, information can also be obtained from the absence of coherent data.

Figure 4 is an interferogram of the Fagradalsfjall volcano after the 2021 eruption. This image contains a well-defined area of noise, within which the surface has changed so considerably between the radar images that a coherent signal could not be obtained. This surface change is generated by the outpouring of lava and the extent of the noise reflects the extent of the lava field.

Figure 4 – Interferogram from July 2021 alongside a published map of the lava field. Note: There is a small distortion on the interferogram projection.

A timelapse of coherence maps from April 2021 to November 2021 is shown in Figure 5. Blue represents poor coherence (e.g., over the lava field) and yellow represents good coherence (e.g., over the stable rocky surface). Between April and May, the lava field rapidly expands and surges down the surrounding valleys. Over the summer months the lava field maintains its extent, but the consistent lack of coherence implies the field is still evolving. Towards the end of the timelapse, areas become coherent again as the flow rate decreases and the fringes of the lava field solidify. Unfortunately, winter snowfall causes a regional loss of coherence by November.

Figure 5 – Timelapse of coherence maps over lava field from April 2021 to November 2021

The lava field planform determined by InSAR shows excellent consistency with a map published using alternative satellite imagery and field observations. Our work demonstrates the suitability of InSAR in tracking lava flows. In fact, InSAR has some significant advantages over other satellite techniques. Radar data is regularly obtained, free to access and has sufficient resolution. Furthermore, radar signals are not obstructed by hazy atmosphere (e.g., cloud cover or volcanic smoke) and do not require sunlight.

2022 uplift near thermal plant

Significant surface deformation on the Reykjanes Peninsula is not limited to spectacular volcanic and seismic events. Figure 6 is a map of vertical displacement between March and May 2022, a period of relative geological inactivity. During this time, a dome, up to ~2cm high, developed proximal to Mt. Thorbjorn.

Previous InSAR studies have documented staggered uplift in this area since 2020, attributed to activity within the Svartsengi volcanic system. Activity in this area has potential to pose a risk to nearby populations and infrastructure. The town of Grindavik, the Svartsengi power plant, and the Keflavik airport are all proximal to the epicenter of uplift.

Figure 6 – Vertical displacement map of Reykjanes Peninsula from March to May 2022.

If you'd like more information on this study, or our broader capabilities in the world of InSAR and remote sensing in general, then please feel free to reach out to us for a chat.

Natural Oil Seeps In The Gulf of Mexico

The Satellite Mapping Team — Thu, 02 Feb 2023 08:17:00 GMT

We are excited to see the new research from CGG’s long-standing patron ExxonMobil and partners, around oil seeps in the Gulf of Mexico (GOM) (O’Reilly et al., 2022). This research leans heavily on CGG’s SME-derived global seeps database, up to the 2018 edition.

Over the recent decade, the addition of Sentinel-2 to the arsenal of open access multispectral data enables us to pinpoint new seep sites, which were previously unobservable using traditional radar satellites due to lower oil flux rates. Figure 1B highlights an example of a new seep site found in the Bay of Campeche, offshore Mexico, since the inclusion of this multispectral dataset. Note the subtleness compared to traditionally observed seepage in Figure 1A.

The GOM remains an active and ongoing focus for CGG’s Satellite Mapping oil slick division, and these newly identified seepage sites, and many more across the world, continue to rapidly increase our understanding of fluid migration and petroleum systems.

Figure 1 - Varying fluid flow oil seepage slicks in the Gulf of Mexico. Note the fragmenting nature of oil slick (2), a direct result of pulsed oil releases at the seabed. This type of slick will not uniformly dampen surface capillary waves, resulting in an absence of observability in SAR data. Image © CGG, Contains modified Copernicus Sentinel data, 2020.

For more information on this site, or for further information on our Seep work in the GOM and its key deliverables, please get in touch with our Seep Hunting team.

Email: satellite.info@cgg.com
Telephone: +44 (0)1732 865023
Website: www.cgg.com/satellite
LinkedIn: CGG Satellite Mapping
Twitter: @CGGsatellite

Mine Closure 2022

The Satellite Mapping Team — Mon, 03 Oct 2022 16:00:00 GMT

We are attending the Mine Closure 2022 conference and exhibition in Brisbane on October 4th through 6th 2022.

CGG Satellite Mapping's Project InSAR Scientist Ed Sage will be there alongside his colleague Aletta Rooplal from CGG Minerals & Mining.

Ed is presenting a paper entitled "InSAR monitoring of a challenging closed mine site with corner reflectors" in Session 14: Planning, relinquishment and legacy management (2) in Ballroom B at 10:35 on Thursday 6th October.

Swing by the CGG booth or reach out to us directly to chat about MineScope and our expertise in deploying cutting-edge satellite remote sensing solutions across active and abandoned mine sites.

Email: satellite.info@cgg.com
Telephone: +44 (0)1732 865023
Website: www.cgg.com/satellite
LinkedIn: CGG Satellite Mapping
Twitter: @CGGsatellite

IPA Convex 2022

The Satellite Mapping Team — Mon, 19 Sep 2022 08:00:00 GMT

We are attending the 46th IPA Convention and Exhibition in Jakarta on September 21st to 23rd 2022.

CGG Satellite Mapping's Business Development Manager Duncan Witts will be there alongside colleagues from CGG Earth Data and CGG Natural Resource Science & Analytics.

If you are attending please get in touch with Duncan to chat about Natural Seeps, Geological Mapping and Modelling, SeaScope and other "Satellite Mapping" offerings.

Email: satellite.info@cgg.com
Telephone: +44 (0)1732 865023
Website: www.cgg.com/satellite
LinkedIn: CGG Satellite Mapping
Twitter: @CGGsatellite

Newly discovered oil seeps confirm potential for offshore Argentina

The Satellite Mapping Team — Thu, 15 Sep 2022 14:07:47 GMT

Extensive oil seepage in the Argentinian offshore has been discovered by CGG.

One of the most anticipated wells of 2022, Argerich-1, looks to be spudded in the coming months offshore Argentina. The area is considered analogous to the basins of Namibia where Venus and Graff have refocused frontier exploration to the southern Atlantic. In turn, the Seep Hunting team at CGG Satellite Mapping have undertaken a detailed study of the archive of satellite SAR (Synthetic Aperture Radar) data and multispectral optical imagery across the Argentina sedimentary basins, and the results – even by global standards – are nothing short of spectacular.

Figure 1 – Stunning oil seepage slicks, offshore Argentina. Note the Similarity in length and sinuosity, indicative of similar flow rates of oil from the seabed. Image © CGG, contains modified Copernicus Sentinel data, 2018.

The identification and classification of natural oil seeps observed in Argentina’s waters are testament to the domain expertise and experience of our interpreters. For the past three decades, we have worked with partners and clients, developing a robust understanding of the episodic nature of seepage in a variety of marine environments across the globe and their manifestation in a variety of remote sensing data sources. We utilize a unique detection technique that involves advanced processing and expert interpretation of Earth observation (EO) data that enables confident identification and categorization of slicks on the ocean surface. Key to unlocking the slick distribution across this area of the South Atlantic was targeting weather compliant scenes acquired in the summer months when Argentinian waters experience a drop in ocean bottom pressure. Such variations can lead to increased seepage activity.

Amongst the over 700 natural oil seepage slicks we have identified offshore Argentina, three are of particular relevance given their proximity to the Argerich-1 well. Located up dip of the CAN-100 acreage in CAN-109, the seepage slicks provide evidence of a working hydrocarbon system further offshore than Corona Austral-X1 and Cruz del Sur-X1 wells, and indeed may hold geochemical information key to linking the prospectively of the source interval feeding the targeted traps of the upcoming well.

The fact that this seep was even observed was serendipitous. The European Space Agency (ESA) Sentinel-1 satellite acquired only five longer descending orbit pass acquisitions in early 2022 (prior to shortening the swath from approximately 4 minutes to 2 minutes of acquisition time to conserve resources). This small number of lengthened overpasses, that extended across the CAN-109 acreage, are the only open-access EO data sources available at a spatial resolution sufficient to potentially identify oil seepage slicks with confidence (prior to even considering met ocean conditions at the time of acquisition).

Figure 3 - Temporally repeating oil slick observed in CAN-109, indicative of natural oil seepage through the water column (70m). Interpretation and image © CGG, Contains modified Copernicus Sentinel data, 2022.

Whilst open-access EO data often provides an highly valuable initial input data source, we are able to overcome poor or totally lacking open-access EO data coverage by drawing upon the impressive capabilities of growing numbers of commercial satellite constellations. Site-specific tasking of such missions allows us to perform high-resolution seep hunting studies built upon EO data acquisitions that are optimised to maximise our chance of detecting any natural seeps that may be present. We have experience of performing such studies globally with great success.

For more information around our Argentina natural seeps study and its key deliverables, please get in touch with our Seep Hunting team.

Email: satellite.info@cgg.com
Telephone: +44 (0)1732 865023
Website: www.cgg.com/satellite
LinkedIn: CGG Satellite Mapping
Twitter: @CGGsatellite

Lithium Battery and Energy Metals Conference 2022

The Satellite Mapping Team — Tue, 13 Sep 2022 19:00:00 GMT

We are attending the Lithium Battery and Energy Metals Conference 2022 in Perth on September 14th and 15th 2022.

CGG Satellite Mapping's Business Development Manager Duncan Witts will be there alongside CGG Minerals & Mining's Aletta Rooplal.

Swing by the CGG booth or reach out to us directly to chat about our geological mapping and lithium exploration expertise and other "Satellite Mapping" offerings.

Email: satellite.info@cgg.com
Telephone: +44 (0)1732 865023
Website: www.cgg.com/satellite
LinkedIn: CGG Satellite Mapping
Twitter: @CGGsatellite