DBPapers
DOI: 10.5593/SGEM2014/B23/S10.014

CONTRIBUTIONS TO THE METHODOLOGY OF THE USE OF SATELLITE REMOTE SENSING METHODS IN STUDIES ON GEOTHERMAL ANOMALIES

T. Pirowski, W. Drzewiecki
Wednesday 1 October 2014 by Libadmin2014

References: 14th International Multidisciplinary Scientific GeoConference SGEM 2014, www.sgem.org, SGEM2014 Conference Proceedings, ISBN 978-619-7105-12-4 / ISSN 1314-2704, June 19-25, 2014, Book 2, Vol. 3, 109-120 pp

ABSTRACT
In studies on the geological environment, besides the traditional geophysical measurement techniques, remote sensing data is used. The optical multispectral data is still the first and most commonly used. The importance of radar data has recently increased due to the development of this type of satellite imaging systems. The use of thermal data, namely, the data registered in the so-called long-wave infrared is still relatively limited. The reason may be the relatively small number of satellite sources of this type of imaging data (limited to missions of Landsat and Terra/Aster systems), and the relatively low spatial resolution of the data, making its interpretation difficult. The presented methodological aspects of satellite data use are supported by tests and experience gained within three independent research experiments related to various types of geothermal anomalies. In each case different configuration of various factors occurred, i.e. the topographic characteristics of the area, the set of imaging data (sources and quantity of data, registration season of a year), identification of location (spatial range) and description of geothermal anomalies by means of geophysical methods. The difficulty of remote sensing method application was also associated with the fact that in each of the cases studied the difference in temperature observed in soil layers close to the surface at the area of the anomaly and in its surroundings reached only several degrees. The untypical nature of each of the experiments enforced the answer to the following questions:

  • to what extent it is possible to use optical multispectral data as complementary to thermal data?
  • how the selection of data sets can be made and within the data selected
  • which channels should be used, what are the factors determining their usefulness, which techniques of multispectral image processing are effective?
  • how to eliminate, restrict or consider the factors influencing on temperature in calculations, such as insolation or the diversified land cover and landuse, canopy, etc.?
  • which solutions should be used to enable the generalisation of the result in the dynamically changing local spatial conditions?
  • which solution should be used in case well-known anomalies are confirmed, and which solution should be used to detect the potential places of their occurrence?

In the article, variants of methodical solutions adjusted to the specific nature of individual research problems are presented. The studies have shown that:

  • reliance on the available satellite data registered in the thermal band, such as Landsat and Terra/Aster, while maintaining the relevant methodical solutions enables to confirm the occurrence of geothermal anomalies;
  • the remote sensing methods may provide support for defining the range of the geological structures associated with the occurrence of the geothermal anomalies.

Keywords: thermal remote sensing, geothermal anomalies, LANDSAT, ASTER