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Application of ALOS and Other Satellite Data to Study Landscape Changes
Related to Petroleum Fields and Their Exploitation at the Timan-Pechorian
petroleum province JAXA PI 200
Irina Smirnova (1)
, Alexandra Rusanova (1)
(1) Institute of Remote Sensing Methods for Geology (VNIIKAM), Pulkovskoe shosse, 82, St.-Petersburg,
Russia, Phone: (7) 812 3637192, Fax: (7) 812 3637196, E-mail: [email protected]
Abstract
The final report on the project titled “Application of
ALOS Data to Study Landscape Changes Related to
Petroleum Fields and Their Exploitation at the North
West of Russia” (JAXA PI 200) is presented.
The objective of research was the study of landscape
changes above petroleum fields caused by natural factors
(neotectonic movements, subsidence, fracturing of rocks,
cryogenic processes, global warming and others), as well
as human activity, connected with petroleum fields
exploration and exploitation (disturbance and pollution
of natural environment due to drilling, accidents on wells,
oil pipelines, subsidence of the surface and others), using
ALOS and other satellite data. Some test sites located in
the northern part of the Timan-Pechorian petroleum
province were chosen for fulfilment of the project.
Satellite data acquired in different years (1985 - 2001) by
various sensors are collected and processed for these
areas. ALOS data (AVNIR2, PRISM, PALSAR),
acquired in 2006-2008 has been used to study geological
processes and landscape changes. Processing and
comparison of multitemporal satellite data were realized
on the basis of GIS software (ERDAS Imagine, ENVI
module SARScape, Map Info). Detection of changes was
made in automatic mode using the methods of
differencing, color compositing and other as well as by
visual interactive analysis. The advantage of ALOS
AVNIR, PRISM, and PALSAR data for study of
cryogenic processes, geological structures and landscape
changes has shown.
Keywords: ALOS, landscape changes, cryogenic
processes, geological structure, petroleum fields.
1. INTRODUCTION
The main objective of our research was the study of
landscape changes above petroleum fields caused by
natural factors as well as human activity using ALOS
(AVNIR, PRISM, PALSAR) and other satellite data. The
target objectives were:
to estimate ALOS data for study of geological
structure and landscape changes and compare them
with other satellite data;
to identify the effective tool for monitoring of
different landscape changes using multisensor,
multitemporal satellite data by employing different
change detection techniques;
to detect the changes caused by natural factors such
as cryogenic processes development (preferably
changes in thermokarst lakes and shore line) and
changes caused by human activity (mechanical
disturbance of a surface and pollution of lakes and
rivers connected to construction of oil pipelines and
oil terminal, drilling of wells, building of roads and
other industrial objects,) using ALOS and other
multitemporal satellite data on the test sites located
in the northern part of Timan-Pechorian petroleum
province;
to estimate level of suspended sediments
concentration in polluted lakes;
to estimate the expression of geological structures
and faults including structures controlled petroleum
traps distribution on ALOS and other satellite data .
2. GEOLOGICAL SETUP OF THE AREA
The study area is situated in the northern part of Timan-
Pechorian petroleum province (North-West of Russia) in
subarctic region (tundra and forest tundra zone). It
characterized by extreme climatic conditions and
underlined continuous permafrost with thickness ranging
from 50 to more than 200 meters that has caused wide
development of cryogenic processes such as thermokarst,
thermoerosion, frost swelling of hillocks, polygonal
grounds, slope processes and others. Quaternary deposits
are widespread in this area and consist of moraines,
glaciofluvial, fluvial, glaciolacustrine and lacustrine
sediments. Quaternary deposits sometimes mask surface
expression of deep geological structures, but distribution
of the different forms of glacial relief which clearly
distinguished on satellite images (lakes, sand hills,
moraine ridges, in particular edge of glacial deposits etc.)
as well as swamps, erosion pattern and linear landscape
elements are connected with distribution of geological
petroleum structures. Global warming can cause melting
This document is provided by JAXA.
of permafrost and the changes in cryogenic processes
development, which can complicate the exploitation of
petroleum fields and lead to accidents on oil and gas
pipeline. The area of the study of landscape changes and
geological processes using ALOS AVNIR and PALSAR
data has shown on Fig. 1. The results of satellite image
processing are represented for 6 test areas (Fig. 1).
Fig. 1 Test areas location
Test areas 1 and 2 are situated in the Varandey region.
Active industrial development of the territory is
conducted during more than 70 years. Recently the
industrial development of the area was essentially made
active in connection with construction of the oil terminal
"Varandey", being basic object for export of petroleum
extracted in the Timan-Pechorian petroleum province,
and new oil pipeline “Southern Khilchuou – Varandei”
coming into service in 2008. New engineering objects of
various assignments are erected: industrial,
infrastructural, linear, therefore is very important the
development of questions connected to probable negative
changes of conditions of the area. The problems of
rational development of this territory essentially are
complicated by presence of permafrost, sensitive to
external influences, first of all to global or regional
climatic changes and also to local changes connected to
man-made activity: exploitation of petroleum fields and
construction of engineering objects. Test area 1 includes
coastal zone of Barents Sea and test area 2 includes
Varandey petroleum field.
Test areas 3, 4, 5, 6 are located in the Usinsk region
includes prospective petroleum-bearing structures and
intensive exploited petroleum fields Usinskoe, Vozeiskoe
and others. The network of seismic profiles, wells, oil
and gas pipelines, roads, building and other infrastructure
are clearly distinguished on satellite images. Exploitation
of petroleum fields disturbs natural environment and
cause strengthening of intensity of cryogenic processes.
3. DATA USED
The following multispectral data was analyzed and
processed for change detection and study of cryogenic
geological processes:
─ ALOS AVNIR2 Path Num. 249, Frame Num. 2200,
2210, 2220, 2230, 2240, 2250, 2260, acquired
2006/10/09.
─ ALOS AVNIR2 Path Num. 249 Frame Num. 2190,
2200 acquired 2007/07/12
─ ALOS AVNIR2 Path Num. 245 Frame Num. 2200,
2210, 2220, 2230, 2240, 2250 (2007/06/20); Path Num.
254 Frame Num. 2190, 2200, 2210, 2220, 2230, 2240
(2007/07/05); Path Num. 257 Frame Num. 2200, 2210,
2220, 2230, 2240 (2007/07/10);
─ PRISM Path Num. 241 Frame Num. 2200, 2195, 2205,
2250, 2255, 2260 (2006/07/11),
For comparison with ALOS AVNIR2 data the following
images were used:
─ LANDSAT 4 TM acquired in August 03, 1988 and in
June 25, 1988;
─ LANDSAT 7 ETM+ acquired in July 21, 2000;
─ KFA 1000 acquired in June, 1985.
The following radar data was used for study of
geological structures and landscape:
─ ALOS PALSAR acquired in June, July and August of
2006 and 2007 (wavelength 23,5 cm - L band, FBS and
PLR modes);
─ JERS-1 SAR acquired in December of 1996 and in
August of 1997 (wavelength 23,5 cm - L band, HH
polarization);
─ RADARSAT-1 acquired in February of 2001
(wavelength 5,6 cm - C band, HH polarization, standard
beam 3).
4. METHODOLOGY
Computer processing and analysis of the data were
realized on the basis of GIS software (ERDAS Imagine,
ENVI module SARscape, Map Info) and includes:
─ creation of databases of satellite images obtained in
different years;
─ preliminary processing of satellite images (image to
image rectification, relative calibration of multitemporal
images; a speckle filtering of SAR images using Frost
filter);
─ interactive interpretation of different satellite images
with compilation of vector layers,
─ processing of multitemporal images for change
detection in automatic mode (color compositing, image
differencing, Principal Components Analysis), as well as
using visual interactive analysis;
─ creation of spectral curves of test objects using
different bands of multitemporal satellite images;
─ different methods of classification;
─ lineament analysis (extraction of lineament in
automatic mode, analysis of lineament density).
The choice of processing methods depends on research
objectives and used satellite data (radar or multispectral).
When using multitemporal satellite images for changes
detection the images should be radiometrically calibrated
in order to reduce the differences of acquisition terms
that may cause the appearance of false changes. One of
This document is provided by JAXA.
the most effective methods for this purpose is relative
radiometric calibration, i.e. that brightness values of one
image are corrected to match these of other one (serving
as a reference image). In our study ALOS AVNIR 2
image (2007) was a reference image. LANDSAT 4 TM
(1988) and 7 ETM+ (2000) were corrected in relation to
ALOS AVNIR 2 image. For radiometric calibration
unchanged reference sites having identical brightness on
all three satellite images (clear lakes with low value of
brightness, and the sand grounds with high value of
brightness) were chosen. The calibration of one image in
relation to another is made using Eq. 1.
L' = a *L + b (1)
Where L' – value of brightness of calibrated image,
L - value of brightness of initial image,
a (gains), b (offset) - coefficients of the equation.
The coefficients a and b, used in Eq. 1, are calculated
using the system of two linear equations Eqs. 2, 3
Y1 = b+aX1 (2)
Y2 = b+aX2 (3)
Where X1, X2 – values of brightness within the limits of
reference sites (sand – clear lakes) of the image which is
corrected; Y1, Y2 – values of brightness within the limits
of reference sites (sand – clear lakes) of the image to
which calibration is made.
Most simple approach for change detection in automatic
mode is the generation of RGB color composite from
pair of images (bands with equal wavelength) acquired in
different years. If color composite images (RGB) is
generated from pair of multitemporal images where R -
the image acquired later, and G and B - the image
acquired earlier, objects with increased brightness, will
have red color on the resultant image, for example, sites
of the coast accumulation and dried up lakes, polluted
lakes, roads, areas of drilling and new engineering
objects. Sites with decreased brightness that can be
connected with increase in soil moisture, a deepening of
lakes, occurrence of new lakes, sites of coast abrasion,
etc. will have blue color.
To create difference image the subtraction of earlier
image from later is carried out. On the resultant image
objects which brightness has increased will have light
color, and dark – objects which brightness has decreased.
Unchanged objects will have gray color. To receive more
precise picture of changes, brighter objects are
represented by red color, and objects which brightness
has decreased are blue.
For interpretation of PALSAR polarimetric data RGB
composition and method of Pauli de composition [1]
were used.
4. RESULTS AND DISCUSSION
4.1. Results of detection of the changes caused by
cryogenic processes.
The analysis of ALOS AVNIR 2 data acquired in July of
2007 in the northern part of Timan-Pechorian petroleum
province confirms the tendency of thermokarst lakes
drainage that has shown in our previous works which
were devoted to comparison of LANDSAT imagery
obtained in different years (in July-August of 1986-1988
and in July-August of 2000) [2], and these LANDSAT
images with ALOS AVNIR 2 data acquired in October
of 2006 [3]. Dried thermokarst lakes are situated mainly
within the limits of low seaside plains, lacustrine and
marsh landscapes composed mainly peat and sandy
sediments, and also within the large river valleys. The
increase of lake areas or formation of new lakes
practically does not occur (except the lakes, which were
formed due to man-made activity). It testifies that
processes of global warming have not find yet reflection
in changes of thermokarst lakes. In fact when frozen
ground intensively thaws, surface subsidence and
formation of new lakes should occur. On ALOS
AVNIR2 data we can observe frost swelling of hillocks
on the bottom of dried thermokarst lakes that testifies
that the ground frosting is increased (Fig. 2).
Fig. 2 ALOS AVNIR2 RGB 432 (10.09.2006). Frost
swelling of hillocks on the bottom of dried lakes
The advantage of ALOS AVNIR2 data for study of
cryogenic processes is their high spatial resolution that
allows to detect microforms of relief caused by ground
frosting, as well as microforms of relief that indicate
petroleum structures, small lakes which can caused by
permafrost melting, changes in character of vegetation
and other features, which poorly distinguished on
LANDSAT images with spatial resolution 30 meters.
4.2. Results of detection of the changes in a coastal
zone and thermokarst lakes in Varandey region.
On the test area 1 ALOS AVNIR 2 (21/07/2007) and
LANDSAT 4 ТМ (03/08/1988) have been processed for
change detection using two techniques: color
compositing and image differencing. Results of
processing on test area 1 (color composite image RGB,
where R – ALOS AVNIR2 and G, B – LANDSAT 4
ТМ) have allowed to reveal changes in a coastal zone of
sea within accumulative terrace: sites of shore abrasion
(blue color) and sites of coast accumulation, including
new spit formation, increase of the area of sand deflation
and the area of new constructions (red color).
This document is provided by JAXA.
Fig. 3 Test area 1. Color composite image. RGB: R – ALOS AVNIR2 (3 band), 2007; G and B – Landsat 4
TM (3 band), 1988. The figures with arrows specify the areas of changed objects of coastal zone. 1-10 –
numbers of changed thermokarst lakes
Fig. 4. Test area 1. Result of change classification based on difference ALOS AVNIR2 (3 band), 2007 and
Landsat 4 TM (3 band), 1988 (red – sites with increased brightness value; blue – sites with decreased
brightness value)
This document is provided by JAXA.
The area of these changed sites is calculated (Fig. 3).
Linear measurements in a coastal zone have shown, that
since 1988 up to 2007 displacement of a coastal line due
to abrasion near settlement Varandey reached 20-30 m
and 30-90 m to the east and to the west from Varandey
that corresponds to field measurements [4]. Abrasion
has been increased due to man-made activity, but near
settlement Varandey speed of abrasion was slowed
down due to construction for coast protection.
Mechanical disturbance of the surface and new
constructions also have a red color on RGB images. For
example at construction of coastal oil reservoirs the area
of disturbance has reached 1 km2 (Fig. 3).
Within the limits of lacustrine and marsh plane
significant changes of thermokarst lakes are detected
(Fig. 3). The lake 1 has dried up, lakes 3, 4, 5 (dark red
color) became shallower due to natural processes.
Activisation of thermokarst processes due to man-made
activity (blue color) is reflected in increase of surface
moisture (shores of lake 5), increase of lakes deep (lake
2). Variations of red color from dark red up to bright red
reflect a degree of lakes pollution: minimal (lake 7),
average (lake 6) and maximal (lakes 8, 9, 10) (Fig. 3).
The changes detected on difference image (Fig. 4)
obtained using image differencing method on the basis
of the same images that RGB (Fig. 3) are similar. The
classification of changes was made and brighter objects
are represented by red color, and objects which
brightness has decreased are blue (Fig. 3). But on this
image it is impossible to distinguish the dried up lakes
and polluted lakes as well as lakes, which depth (or
pollution) has changed slightly (dark red color on RGB).
On the test area 2 the satellite images received in three
dates were analyzed: LANDSAT 4 ТМ (03/08/1988),
LANDSAT 7 ЕТМ + (21/07/2000) and ALOS
AVNIR 2 (05/07/2007) (Fig. 5). The analysis of spectral
characteristics using Bands 1, 2, 3, 4 of these images
was spent to distinguish the polluted lakes from dried up
thermokarst lakes and to estimate level of suspended
sediments concentration in polluted lakes. Test objects
where spectral characteristics were measured are shown
on Figure 5.
Test objects 1-4 are lakes polluted up to 2007, which
was clear in 1988 and 2000, test object 5 is shallow lake
with insignificant increase of suspended sediments
concentration, test objects 6-8 are dried up lakes and
test object 9 is lake with salt water. The spectral curves
have been made for these objects (Fig. 6). The analysis
of the curves has shown that unchanged thermokarst
lakes have identical characteristics of spectral brightness
in images of all years, averaging in the first band - 70, in
the second - 40, in the third - 25, in the fourth - 8 units.
In the polluted lakes (test objects 1-4 –
A
B
C
Fig. 5 Test area 2. A – Landsat 4 RGB 421
(03.08.1988); B – Landsat 7 RGB 421
(21.07.2000); C – ALOS AVNIR2 RGB 421
(12.07.2007); red digits – test objects location and
their number
Fig. 6 a, b, c, d) spectral brightness on ALOS AVNIR2
(2007) in the first band increases up to 80-102, in the
second - till 51-96, in the third - till 45-90, in the fourth -
till 15-30 units, depending on a degree of pollution. Test
object 1 has minimal pollution (Fig.6 a), test object 3 –
maximal (Fig. 6 c). Thus a degree of lake pollution as a
result of man-made activity has increased approximately
in 2,5 - 3,5 times. The spectral curve of shallow lake
where suspended sediments concentration was increased
insignificantly due to natural processes is presented on
Figure 6 e (test object 5) for comparison.
This document is provided by JAXA.
Bri
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a
Bri
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b
Spectral bands Spectral bands
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c
Bri
gh
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d
Spectral bands Spectral bands
Bri
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e
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f
Spectral bands Spectral bands
Bri
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g
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h
Spectral bands Spectral bands
Fig. 6 Test area 2. Comparison of spectral curves using LANDSAT 4, 1988 (red), LANDSAT 7, 2000 (blue) and
ALOS AVNIR2, 2007 (green) for different test objects: a, b, c d – objects 1-4; e – object 5; f – object 6;
g – object 8; h – object 9
This document is provided by JAXA.
At dried up from 1988 till 2000 thermokarst lake (Fig. 6 f)
spectral brightness in 1, 2, 3 bands is increased
insignificantly but in 4 band it increases from 8 till 40-50
units and character of spectral curve is changed. This
spectral curve become similar to spectral curve of old
dried up lake, which was dry in all years (Fig. 6 g).
The results of the works in the Varandey region in more
detail were discussed in [5].
4.3. Results of detection of the changes caused by man-
made activity in the Usinsk region
Comparison of Japanese ALOS AVNIR2 (October 2006)
and Russian photographical false color image KFA 1000
with wavelength 560 - 810 nm (June 1985), which have
almost identical spatial resolution (ALOS AVNIR2 –
10 m, KFA 1000 – 8 m) was made for the test area 3 (Fig.
1). The techniques of various data fusion (color
compositing, image differencing, Principle Component
Analysis) for detection of landscape changes caused by
human activity have been estimated for this area and other
sites [6]. For example, the result of Principle Components
Analysis (test area 3) is presented on Figure 7. The
results are quite satisfactory and allow detecting new
roads, buildings, water reservoirs, new lake as objects of
black color.
Fig. 7 Test area 3. Result of PCA (ALOS
AVNIR and KFA). Image of third principal
component
The numerous changes connected with human activity are
detected using method of color compositing of
multitemporal radar images, received during 1996-2007
on the test area 4.
4.4. Results of analysis of ALOS PALSAR images for
study of geological structures
Comparative analysis of radar and multispectral data has
shown that radar data (as L band and as C band) are more
effective for structural interpretation especially in the
areas covered by forest for extraction of lineaments and
revelation of active faults and fracture zones, controlled
petroleum traps distribution. But L band (ALOS PALSAR,
JERS-1 SAR) is more prospective for geological
application due to ability of radio waves to penetrate
through a vegetative and soil cover and to reveal the
places with high moisture characterized the fault zones
and microforms of relief indicative for the geological
structures.
On Figure 8 the results of visual interactive analysis of
ALOS PALSAR (FBS mode) is presented. The main line
structures which correspond to faults and fracture zones
and boundaries between different rocks are revealed. The
most of ring structures revealed on PALSAR data are not
visible on multispectral images. These structures control
the distribution of anticlines in sedimentary cover,
including petroleum fields and prospective structures.
Extraction of lineament in automatic mode and analysis of
their density, obtained using ALOS PALSAR permits to
reveal the places with high permeability of rocks and
define prospective sites for oil discovery.
The results of the study have shown that ALOS PALSAR
data is an effective tool for geological application.
Fig. 8 Test area 5. ALOS PALSAR interpretation:
1 – main line structures, 2 – main ring structures,
3 – oil and gas fields
4.3. Results of processing of ALOS PALSAR
polarimetric data
The processing of ALOS PALSAR polarimetric data was
made for test area 6. For interpretation of PALSAR
polarimetric data RGB composition (Fig. 9) and method
of Pauli de composition (Fig. 10) were used.
The Pauli decomposition provides an interpretation of a
full polarimetric data set in terms of elementary scattering
mechanisms: sphere/plate/trihedral (single- or odd-bounce
scattering), dihedral oriented at 0° (double- or even-
bounce) and diplane oriented at 45° (qualitatively related
also to volume scattering). In general decomposition
approach is suitable for discriminating the scattering of
elementary objects.
Results of image analysis (Fig. 10) have allowed to reveal
different types of landscape and vegetation (rare forest –
red color, low trees and bushes – green color, wetland -
blue color, lakes – black color) and to estimate wetland
deep.
This document is provided by JAXA.
Fig. 9 Test area 6. ALOS PALSAR, polarimetric color
coded image (red – hh, green – hv, blue – vv)
Fig. 10 Test area 6. ALOS PALSAR.
RGB image of Pauli decomposition
5. CONCLUSION
The study was concluded as follows:
─ Computer processing of multitemporal ALOS AVNIR
2 and LANDSAT as well as different SAR data for
change detection using various techniques (color
composite RGB, image differencing Principle
Components Analysis) is effective approach.
─ The technique of color composite RGB is most simple
and fastest way for change detection. It allows detecting
and differentiating changes connected with human
activity and natural processes.
─ The technique of image differencing with
classification of changes allows to obtain more evident
picture of changes, but it results depend on size of the
chosen threshold, and different types of objects can be
carried to one class, for example, the dried up and
polluted lakes.
─ Comparison of ALOS AVNIR2 and LANDSAT data
has allow to detect the changes caused by human activity
(mechanical disturbance of a surface, pollution of lakes
and rivers and others) and changes caused by natural
factors (changes in coastal line and thermokarst lakes).
─ Analysis of spectral curves of multitemporal ALOS
AVNIR 2 and LANDSAT satellite images has allowed
estimating level of lake pollution due to human activity
and comparing it with level of suspended sediment
concentration caused by natural processes.
─ ALOS AVNIR, PALSAR and PRISM data due to
their high spatial resolution is an effective tool for study
of cryogenic processes and landscape changes.
─ ALOS PALSAR data is an effective tool for geological
application due to ability of radio waves to penetrate
through a vegetative and soil cover and to reveal the
places with high moisture characterized the fault zones
and microforms of relief indicative for the geological
structures.
.
─ ALOS PALSAR polarimetric data allows to reveal
new information to study vegetation cover especially
wetland vegetation.
6. ACKNOWLEDGEMENT
This research is conducted under the agreement of JAXA
Research Announcement titled “Application of ALOS
Data to Study Landscape Changes Related to Petroleum
Fields and Their Exploration and Exploitation” (JAXA PI
200). The authors are grateful for cooperation and
assistance provided by Japan Aerospace Exploration
Agency (JAXA) and EORC Order Desk.
7. REFERENCES
[1] S.R. Cloude and E. Pottier, “A review of target
decomposition theorems in radar polarimetry”, IEEE
Trans. GRS, vol. 34(2), pp. 498-518, Mar. 1996.
This document is provided by JAXA.
[2] I. Smirnova, A. Rusanova, and N. Smirnova,
“Processing and Interpretation of Remotely Sensed Data
based on GIS for Study of Exogenic Geological Processes
in the North-Eastern part of Timan-Pechorian Petroleum
Province”, Proceedings of III International Conference
“Remote Sensing of Natural Environment”, Minsk,
Byelorussia, 2006, pp. 166-168.
[3] I. Smirnova, A. Rusanova, “Application of ALOS and
Other Satellite Data to Study Landscape Changes Related
to Petroleum Fields and Their Exploration and
Exploitation”, Proceedings of the First Joint PI
Symposium of ALOS Data Nodes for ALOS Science
Program in Kyoto, 2007.
[4] S.A. Ogorodov, “Morphology and dynamics of coast
of the Pechora sea”, Works of Institute of Oceanology, v.3,
Varna, Bulgaria, pp. 77-86, 2001.
[5] I. Smirnova, A. Rusanova, “Monitoring of Landscape
Changes Due to Petroleum Fields Exploitation,
Construction of Oil Pipelines and Oil Terminal in the
Northern Part of the Timan-Pechorian Petroleum Province
Using Multitemporal ALOS and LANDSAT Data”,
Proceedings of ALOS PI 2008 Symposium. Island of
Rhodes, Greece, 3-7 November 2008.
[6] A. Rusanova, I. Smirnova, “Comparative Analysis and
Computer Processing of Japanese ALOS AVNIR, Russian
KFA 1000 and Radar (Japanese JERS-1 and Canadian
Radarsat) Multitemporal Satellite Data for Change
Detection”, Proceedings of the First Joint PI Symposium
of ALOS Data Nodes for ALOS Science Program in Kyoto,
2007.
This document is provided by JAXA.