Applications of Satellite Earth Observations section - NEODAAS: Providing satellite data for efficient research

The NERC Earth Observation Data Acquisition and Analysis Service (NEODAAS) provides a central point of Earth Observation (EO) satellite data access and expertise for UK researchers. The service is tailored to individual users’ requirements to ensure that researchers can focus effort on their science, rather than struggling with correct use of unfamiliar satellite data

Site Characterization Using Integrated Imaging Analysis Methods on Satellite Data of the Islamabad, Pakistan, Region

We develop an integrated digital imaging analysis approach to produce a first-approximation site characterization map for Islamabad, Pakistan, based on remote-sensing data. We apply both pixel-based and object-oriented digital imaging analysis methods to characterize detailed (1:50,000) geomorphology and geology from Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) satellite imagery. We use stereo-correlated relative digital elevation models (rDEMs) derived from ASTER data, as well as spectra in the visible near-infrared (VNIR) to thermal infrared (TIR) domains. The resulting geomorphic units in the study area are classified as mountain (including the Margala Hills and the Khairi Murat Ridge), piedmont, and basin terrain units. The local geologic units are classified as limestone in the Margala Hills and the Khairi Murat Ridge and sandstone rock types for the piedmonts and basins. Shear-wave velocities for these units are assigned in ranges based on established correlations in California. These ranges include Vs30-values to be greater than 500 m/sec for mountain units, 200–600 m/sec for piedmont units, and less than 300 m/sec for basin units. While the resulting map provides the basis for incorporating site response in an assessment of seismic hazard for Islamabad, it also demonstrates the potential use of remote-sensing data for site characterization in regions where only limited conventional mapping has been done

Satellite monitoring of harmful algal blooms (HABs) to protect the aquaculture industry

Harmful algal blooms (HABs) can cause sudden and considerable losses to fish farms, for example 500,000 salmon during one bloom in Shetland, and also present a threat to human health. Early warning allows the industry to take protective measures. PML's satellite monitoring of HABs is now funded by the Scottish aquaculture industry. The service involves processing EO ocean colour data from NASA and ESA in near-real time, and applying novel techniques for discriminating certain harmful blooms from harmless algae. Within the AQUA-USERS project we are extending this capability to further HAB species within several European countries

Applying Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) spectral indices for geological mapping and mineral identification on the Tibetan Plateau

The Tibetan Plateau holds clues to understanding the dynamics and mechanisms associated with continental growth. Part of the region is characterized by zones of ophiolitic melange believed to represent the remnants of ancient oceanic crust and underlying upper mantle emplaced during oceanic closures. However, due to the remoteness of the region and the inhospitable terrain many areas have not received detailed investigation. Increased spatial and spectral resolution of satellite sensors have made it possible to map in greater detail the mineralogy and lithology than in the past. Recent work by Yoshiki Ninomiya of the Geological Survey of Japan has pioneered the use of several spectral indices for the mapping of quartzose, carbonate, and silicate rocks using Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) thermal infrared (TIR) data. In this study, ASTER TIR indices have been applied to a region in western-central Tibet for the purposes of assessing their effectiveness for differentiating ophiolites and other lithologies. The results agree well with existing geological maps and other published data. The study area was chosen due to its diverse range of rock types, including an ophiolitic melange, associated with the Bangong-Nujiang suture (BNS) that crops out on the northern shores of Lagkor Tso and Dong Tso ("Tso" is Tibetan for lake). The techniques highlighted in this paper could be applied to other geographical regions where similar geological questions need to be resolved. The results of this study aim to show the utility of ASTER TIR imagery for geological mapping in semi-arid and sparsely vegetated areas on the Tibetan Plateau.Comment: 6 pages, 4 figures, 2 tables, Published in the International Archives of the Photogrammetry, Remote Sensing, and Spatial Information Science, Volume XXXVIII, pp. 464-469. For associated web page, see http://www.isprs.org/proceedings/XXXVIII/part8/headline/PS-1%20Interactive%20PresentationWG%20VIII5.htm

A review of geothermal mapping techniques using remotely sensed data

Exploiting geothermal (GT) resources requires first and foremost locating suitable areas for its development. Remote sensing offers a synoptic capability of covering large areas in real time and can cost effectively explore prospective geothermal sites not easily detectable using conventional survey methods, thus can aid in the prefeasibility stages of geothermal exploration. In this paper, we evaluate the techniques and approaches used in literature for the detection of prospective geothermal sites. Observations have indicated that, while thermal temperature anomalies detection have been applicable in areas of magmatic episodes and volcanic activity, poor resolution especially from space borne data is still a challenge. Consequently, thermal anomalies have been detected with some degree of success using airborne data, however, this is mostly in locations of known surface manifestations such as hot springs and fumaroles. The indirect identification of indicator minerals related to geothermal systems have been applied using multispectral and hyperspectral data in many studies. However, the effectiveness of the techniques relies on the sophistication and innovative digital image processing methods employed to sieve out relevant spectral information. The use of algorithms to estimate land surface temperature and heat fluxes are also applied to aid thermal anomaly detection, nevertheless, remote sensing techniques are still complementary to geologic, geophysical and geochemical survey methods. While not the first of its kind, this review is aimed at identifying new developments, with a focus on the trends and limitations intrinsic to the techniques and a look at current gaps and prospects for the future.Keywords: Geothermal, remote sensing, thermal anomalies, indicator minerals, multispectral, hyperspectra

The influence of cap rock composition on hydrocarbon seep type in the Zagros oil fields, a study using Advanced Spaceborne Thermal Emission and Reflection Radiometer mineral map

The persistent natural hydrocarbon seepage in onshore basins challenges observation and exploration technologies, which are required to document and assess these valuable indications of the presence of oil and gas in the subsurface. This paper aims at demonstrating the relationship between the compositional variation of an evaporite cap rock and the types of seeps occurring at the surface. For this purpose, the multispectral Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data was utilized for mapping mineral variations of a petroleum system in the Zagros oil fields. Relative absorption-band depth (RBD), band rationing and the boosted regression trees (BRT) were applied to enhance and classify the mineral composition of evaporite, sandstone, and marly limestone formations. The gas seeps were associated with the areas of gypsum-bearing evaporite cap rock while oil seeps were mostly associated with calcite and clay zones within the cap rock, which was more prone to fracturing during the tectonic activities of the basin. It is suggested that the application of remote sensing in the oil and gas industry could be widened by detection of sleep-induced alteration to assess the efficiency of cap rock and to evaluate the productivity of reservoirs at a regional scale

The Maricunga Belt (chilean Precordillera) and its hydrothermal alteration zones as revealed by multispectral remote sensing and field studies

Remote sensing techniques offer a unique chance to analyse and map wide or nearly inaccessable areas under certain geoscientific aspects in relatively short time and at low cost. Therefore geological field campaigns together with multispectral image analysis were carried out for the Maricunga Belt in the chilenean Precordillera, south of the regional mining settlements San Salvador and Potrerillos (Atacama). On the basis of Landsat-TM 5, ASTER, radar-based DGM-data and field mapping/sampling the lithological/structural characteristics of several OH-bearing hydrothermal alteration zones of mostly Neogene age have been investigated because of their high value for future exploration. The often  unknown regional tectonic framework which seems to have controlled the alteration dimensions are also discussed. In order to obtain  reasonable lithological classification criteria for the remote sensing data fundamental statistical selection rules like the optimum index factor  (OIF) were applied to the combination of single TM bands. Furthermore specific band ratios (5/7; 5/4, 5/1) and principal components were  utilized to enhance the spectral properties of the argillized, bleached clay- and/or silica-rich alteration surfaces. Additional spectral measurements were carried out for each representative lithological unit of the alteration zones to estimate the quality of the calculated classifications/ratios for geological mapping. In some cases complementary geochemical data has been studied in order to obtain direct clues for understanding the type of some detected hydrothermal alterations. Finally the achieved data was compiled in a geological map which shows more than 20 hydrothermally altered surfaces in relation to the regional geology and the specific tectonic framework. The influence of three major fault systems (the N-S orientated West Fissure System, the NE-SW orientated Inca De Oro System and a poorly described NW-SE System) for the setting of the alterations seems to be obvious

Applicability of multispectral Sentinel data for mineral exploration by use of remote sensing and geospatial technologies:A case study in Northern Chile

Dissertation submitted in partial fulfilment of the requirements for the Degree of Master of Science in Geospatial TechnologiesThe objective of this MSc thesis is to prove that the Sentinel-2 satellite has the same capabilities for mineral exploration than another satellite considered the “reference technology” by the minerals industry. Since there have been an extensive use and applications of the Landsat-8 satellite for mineral exploration, this satellite is considered in this case the “reference technology”. To prove the capability of the Sentinel-2, a sequence of key applications applied on the Landsat-8 satellite for mineral exploration have been carried out using the Sentinel-2 on a specific mine site. Mine site for this investigation is the Escondida mine in northern Chile. Through several remote sensing applications such as band combinations, band ratios, PCA analyses, and pixel´s classification both satellites, Landsat-8 and Sentinel-2 have been tested on Escondida and results have been obtained and discussed. As a conclusion of this analysis, the capability of Sentinel-2 for mineral exploration has been proved, potential improvements have been identified and limitations in its prospective use have been indicated