Alessandro Ferretti

TRE ALTAMIRA S.r.l.

Natural gas is an important source of energy used for domestic, industrial and transport purposes. Its presence is unevenly distributed in the world, and its consumption is subject to large seasonal fluctuations. In addressing this challenge, Underground Gas Storage (UGS) represents an important option to create national strategic reserves and help...

Volcán de Colima is a highly active stratovolcano in western Mexico which presents a significant hazard to over 300,000 people who live within ca 40 km of the volcano. Due to its persistent activity, the volcano is actively monitored and researched, and understanding the patterns of behaviour is vital to accurate hazard assessment. Sentinel-1 SAR i...

The European Ground Motion Service (EGMS), funded by the European Commission as an essential element of the Copernicus Land Monitoring Service (CLMS), constitutes the first application of the interferometric SAR (InSAR) technology to high-resolution monitoring of ground deformations over an entire continent, based on full-resolution processing of a...

The European Ground Motion Service (EGMS) is the most recent addition to the product portfolio of the Copernicus Land Monitoring Service. The EGMS is funded by the European Commission in the frame of the Copernicus Programme and it is implemented under the responsibility of the European Environment Agency. The Service provides consistent, regular,...

Geodetic monitoring involves the repeated measurement of the deformation of the Earth. As discussed here, it is a cost‐effective approach for inferring reservoir integrity and detecting possible leakage associated with the geological storage of greenhouse gas emissions. Most geodetic methods have favorable temporal sampling, from minutes to months...

A recent publication claims that closure phases in SAR interferometry bear no relationship to physical changes of the scatterer, but only to the statistical properties of the averaged pixels. We disprove this claim with a simple counterexample and remind the reader of cases in which closure phases indicate a clear physical content, including the ex...

Subsidence can now be routinely mapped on a national scale thanks to ESA's Sentinel-1 sensors and advanced scalable SqueeSAR® processing. In order to be integrated into existing monitoring programmes, the SqueeSAR® datasets can be calibrated with GNSS measurements. The dense spatial coverage of SqueeSAR® deformation maps captures local deformation...

Geodetic methods comprise one class of geophysical data that are sensitive to changes in effective pressure within operating reservoirs, albeit indirectly through induced deformation. Geodetic observations, which have observation intervals that vary from seconds to days, weeks, or months, generally provide more frequent sampling compared to existin...

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

We demonstrate the potential of satellite Interferometric Synthetic Aperture Radar (InSAR) to identify precursors to catastrophic slope failures. To date, early-warning has mostly relied on the availability of detailed, high-frequency data from sensors installed in situ. The same purpose could not be chased through spaceborne monitoring application...

Satellite interferometric data are widely exploited for ground motion monitoring thanks to their wide area coverage, cost efficiency and non-invasiveness. The launch of the Sentinel-1 constellation opened new horizons for interferometric applications, allowing the scientists to rethink the way in which these data are delivered, passing from a stati...

This work describes a new procedure aimed to semi-automatically identify clusters of active persistent scatterers and preliminarily associate them with different potential types of deformational processes over wide areas. This procedure consists of three main modules: (i) ADAfinder, aimed at the detection of Active Deformation Areas (ADA) using Per...

Cambridge Core - Climatology and Climate Change - Geophysics and Geosequestration - edited by Thomas L. Davis

The In Salah gas development project, initiated in 2004, involves the long‐term storage of waste carbon dioxide associated with natural gas production at several central Algerian fields. Long‐term plans were to store up to 17 million tons of carbon dioxide during the life of the program. The project at In Salah was a pioneering effort in several re...

We present the continuous monitoring of ground deformation at regional scale using ESA (European Space Agency) Sentinel-1constellation of satellites. We discuss this operational monitoring service through the case study of the Tuscany Region (Central Italy), selected due to its peculiar geological setting prone to ground instability phenomena. We s...

Long-term landslide deformation is disruptive and costly in urbanized environments. We rely on TerraSAR-X satellite images (2009-2014) and an improved data processing algorithm (SqueeSAR™) to produce an exceptionally dense Interferometric Synthetic Aperture Radar ground deformation time series for the San Francisco East Bay Hills. Independent and p...

Post-event Interferometric Synthetic Aperture Radar (InSAR) analysis on a stack of 45 C-band SAR images acquired by the ESA Sentinel-1 satellites from 9 October 2014 to 19 June 2017 allowed the identification of a clear precursory deformation signal for the Maoxian landslide (Mao County, Sichuan Province, China). The landslide occurred in the early...

Interferometric processing of series of data acquired over time by synthetic aperture radar (SAR) satellites makes it possible to measure millimetric deformations (typically due to landslides, subsidence and earthquake or volcanic phenomena) and to monitor the stability of terrain and infrastructures. Despite the unique capability to observe very l...

Pre-event and event landslide deformations have been detected and measured for the landslide that occurred on December 3rd, 2013 on the south-western slope of the Montescaglioso village (Basilicata Region, Southern Italy). The event, triggered by 56 h of continuous rainfalls, produced a ground displacement of several meters and created significant...

Petra is a famous archaeological Nabataean city, carved out of stone, hidden by towering sandstone mountains in Jordan. Slopes are continuously affected by rock falls and local sliding events, involving volumes from less than 1 m³ to few hundreds m³. To investigate long-term cliff evolution and the impact on monuments, an area of about 50 km², incl...

Satellite interferometric synthetic aperture radar (InSAR) data have proven effective and valuable in the analysis of urban subsidence phenomena based on multi-temporal radar images. Results obtained by processing data acquired by different radar sensors, have shown the potential of InSAR and highlighted the key points for an operational use of thi...

Pre- event and event landslide deformations have been detected and measured for the landslide that occurred on 3 December 2013 on the south-western slope of the Montescaglioso village (Basilicata Region, southern Italy). In this paper, ground displacements have been mapped through an integrated analysis based on a series of high resolution SAR (Syn...

Underground gas storage in depleted hydrocarbon reservoirs, aquifers or salt caverns can be responsible for surface deformation phenomena. Monitoring surface displacements can support safe reservoir management and provide valuable constraints for modeling the dynamic behavior of a reservoir and help achieve more effective reservoir exploitation wit...

Reservoir monitoring improves our understanding of reservoir behaviour and helps achieve more effective reservoir management and prediction of future performance with obvious economic benefits. It relies on an integrated approach involving both data collection and modelling. Interferometric Synthetic Aperture Radar (InSAR) is a satellite remote sen...

SAR Interfeometry (InSAR) provides high precision ground displacement measurements remotely, using Synthetic Aperture Radar (SAR) images acquired from satellites. Thanks to its effective provision of extensive information over wide areas with high acquisition frequency, InSAR monitoring is used routinely in the management of numbers of Enhanced Oil...

This study presents the spatial and temporal ground-deformation pattern of the Nisyros-Yali volcanic field after the period of the seismic crisis (1996-1998) based on the local GPS network remeasurement and the analysis of Interferometric data (2003-2010) applying the SqueeSAR TM technique. The GPS results indicated intense subsidence in the northe...

The Carajás mineral province encompasses the world´s largest iron reserves with excavation carried out through open pit benching. Mining operations in the area have significant areas of rock mass movements and surface displacements that potentially lead to slope instabilities with risks to personnel, equipment and production. Instabilities can be e...

Reservoir monitoring improves our understanding of reservoir behaviour and helps achieve more effective reservoir management and prediction of future performance with obvious economic benefits. It relies on an integrated approach involving both data collection and modelling. Interferometric Synthetic Aperture Radar (InSAR) is a satellite remote sen...

On 13 January 2012, the Italian vessel, Costa Concordia, wrecked offshore Giglio Island, along the coast of Tuscany (Italy). The ship partially sunk, lying on the starboard side on a 22° steep rocky seabed, making the stability conditions of the ship critically in danger of sliding, shifting and settling. The tilted position of the ship created als...

Satellite radar data for surface deformation monitoring are gaining increasing attention, and not only within the oil and gas community. They provide a powerful tool for re-motely measuring extremely small surface displacements over large areas and long periods of time, without requiring the installation of in-situ equipment. However, apart from re...

Hydrocarbon reservoir operation, i.e. fluid extraction and injection, are responsible for volumetric changes of reservoir itself resulting in surface deformation phenomena (subsidence or uplift). This processes are controlled by the tectonic framework which is responsible for reservoir compartmentalization and/or fault reactivation. Monitoring surf...

Permanent Scatterer SAR Interferometry (PSInSAR) was the pioneer of the so-called “advanced InSAR algorithms”, aiming at detecting and monitoring surface deformation phenomena with satellite radar images. In PSInSAR analyses, signal processing algorithms identify coherent radar targets (PS), exhibiting high phase stability over the entire observati...

Reservoir monitoring improves our understanding of reservoir behavior and helps achieve more effective reservoir management and prediction of future performance with obvious economic benefits. Volumetric changes in reservoirs due to fluid extraction and injection can induce either subsidence or uplift which can trigger fault reactivation and threat...

Interferometric Synthetic Aperture Radar (InSAR) uses satellite radar imagery to precisely measure ground deformation. TRE developed advanced techniques, PSInSARTM and subsequently SqueeSARTM , as a standard monitoring tools in several applications: natural hazards, geothermal, oil and gas, mining, urban and infrastructures monitoring. Thanks to it...

We resolve deformation at The Geysers Geothermal Field using two distinct sets of interferometric synthetic aperture radar (InSAR) data. The first set of observations utilize archived European Space Agency C-band synthetic aperture radar data from 1992 through 1999 to image the long-term and large-scale subsidence at The Geysers. The peak range vel...

Apart from the environmental impact of subsidence and uplift phenomena induced by fluid injection and/or extraction, recent reservoir optimization techniques ask for timely information about many geophysical parameters, both downhole and on the surface. In particular, surface deformation measurements are lately gaining increasing attention within t...

Radar satellites allow the measurement of ground displacement to millimeter accuracy, thanks to a particular technique known as the 'multi interferogram' approach . The latest development of this technique is SqueeSAR™, which allows the identification of discrete ground points and their displacement in time. Underground tunnelling can cause subside...

Remote sensing techniques have been widely used in recent decades to monitor earth surface displacements related to seismic faults, volcanoes, landslides, aquifers, hydrocarbon fields. In particular, advanced InSAR techniques, such as SqueeSAR™, have already provided unique results thanks to both the extension of the area which can be monitored by...

Permanent Scatterer SAR Interferometry (PSInSAR) algorithm identifies coherent radar targets (PS) to detect and monitor surface deformation phenomena. PS typically correspond to point-wise, man-made objects widely available in urban areas. Sometimes, however, it is difficult to apply this technology for un-urban areas, due to a much lower spatial d...

On May 20 and 29, 2012, two earthquakes of magnitudes 5.9 and 5.8 (Mw), respectively, and their aftershock sequences hit the central Po Plain (Italy), about 40 km north of Bologna. More than 2,000 sizable aftershocks were recorded by the Isti-tuto Nazionale di Geofisica e Vulcanologia (INGV; National Institute of Geophysics and Volcanology) Nationa...

Surface deformation monitoring can provide valuable information in assessing the environmental impact of fluid injection and/or extraction activities, evaluating volume/pressure changes in a reservoir, as well as estimating other geophysical parameters. InSAR technologies, providing high-quality, remotely acquired data about surface deformation aff...

In SqueeSAR approach the coherence matrix (CM) is used to optimally estimate the time series of the optical ray-path values of each DS while preserving the information associated to point-wise PS. CM allows also to identify the so called Temporary Coherent Scatterers (TCS), targets whose SNR varies dramatically over time for which it is not possibl...

We describe the state of the art of scientific research on the earthquake cycle based on the analysis of Synthetic Aperture Radar (SAR) data acquired from satellite platforms. We examine the achievements and the main limitations of present SAR systems for the measurement and analysis of crustal deformation, and envision the foreseeable advances tha...

Optical leveling campaigns, tiltmeters, GPS and InSAR are geodetic techniques used to detect and monitor surface deformation phenomena. In particular, InSAR data from satellite radar sensors are gaining increasing attention for their cost-effectiveness and unique technical features, making possible the monitoring of large areas, even revisiting the...

Land subsidence and uplift due to the production/injection of fluids from/into the subsurface have been widely observed worldwide over the last decades and occur for a variety of purposes such as groundwater pumping, aquifer system recharge, gas/oil field development, enhanced oil recovery, geologic CO2 sequestration, underground gas storage and wa...

Coastal regions are increasingly affected by larger storms and rising sea level predicted by global warming models, aggravating the situation in the city of Venice where tidal-induced seasonal flooding coupled with natural and anthropogenic subsidence have been perennial problems. In light of accelerated efforts to protect Venice from the rise in s...

The paper describes the experiences made in the Interreg Alcotra IIIa RiskNat project by three Italian regions, Liguria, Piemonte and Valle d’Aosta, in the field of landslide assessment by means of persistent scatterers radarinterferometry. If a sufficient series of radar images is available, the technique allows, with accuracies in the order of...

EO is an important element for improved knowledge of hazards and risks and a basis for more efficient decision making and better mitigation and preparedness for disasters. Satellite EO can support scientists and operational users for a range of applications. To cite two examples of phases of the risk management cycle this is the case for prevention...