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We applied the Modified Spectral Angle Mapper MSAM and continuum-removal methods to reflectance data obtained in the shortwave infrared regions by the airborne hyperspectral sensor, HyMap, to delineate distribution of the minerals related to hydrothermal alteration and pegmatite. The combination of these two methods was applied to remotely sensed hyperspectral data for the first time in this study. The effectiveness of this method, ‘continuum-removal MSAM’, was confirmed by comparing our mineral index maps with existing mineral maps of the Cuprite region, Nevada, USA. We then produced mineral index maps of southern Namibia using newly observed hyperspectral data. The existence of many pegmatite-and porphyry-type deposits is reported in this study area, where detailed mineralogical mapping based on remote-sensing data has not previously been conducted. Our mineral index maps are consistent with our field survey results, and also with X-ray diffraction analyses and spectral measurements of rock samples. In this study, the continuum-removal MSAM method successfully discriminated hydrothermal alteration minerals such as kaolinite and pyrophyllite, and pegmatite-related minerals such as high-aluminium muscovite and lepidolite in southern Namibia for the first time. The main advantages of our classification method are simplicity and high-precision identification of alteration minerals.

A study of satellite imagery over the Philippines undertaken as part of the US Office of Naval Research Philippine Straits Experiment (PhilEx) found significant high-frequency nonlinear internal wave activity in the waters around the Philippine Archipelago. Along with previously known nonlinear internal wave occurrence in the Sulu Sea and the Sulu Archipelago, the study found new areas of activity near Surigao Strait, within Butuan and Macajalar Bays along the northern coast of Mindanao in the southeastern Bohol Sea, in the Samar Sea, and at the shelf break at the northern end of the Sulu Sea between Palawan and Panay islands. Signatures in the imagery show that the surface expression of internal waves around the Philippines span a considerable spatial scale, from large solitary waves in the Sulu Sea (10-km scale) to very fine (10-m scale) wave packets found in Butuan Bay. This paper presents examples and discusses the characteristics of the nonlinear internal wave signatures observed in synthetic aperture radar and optical sunglint satellite imagery from around the Philippines.

This study observed rock and alteration mineral mapping using HyMap hyperspectral data over the Warmbad district, south of Namibia. The classification result using proposed methods consist of PPI derived from the Spectral Hourglass method and field spectra with the Neural Network classification method show good result for mapping various sericites in pegmatite veins, propylitic alteration of chlorite and epidote, and amphibole in mafic and ultra mafic rock of gabbro, gabbro norite, which are mostly observed in the Warmbad district.

A pegmatite deposit is an important exploration target as a new source of rare metals including rare earth elements. Hyperspectral data provides useful information of surface rocks and minerals associated with mineral deposits. The aim of this study is to delineate pegmatite systems using HyMap data in southern Namibia. As a result of analysis for absorption features of white mica bearing pegmatite and quartz dykes, the distribution of pegmatite systems was successfully mapped in the study area.

Airborne optical hyperspectral remote sensing has been recognized as a regional mineral mapping technique since the late 1980's; however actual data acquisition has been limited due to its high cost. Two new satellite-borne hyperspectral sensors are scheduled to be launched in the next five years by Japan and Germany. Thus, geologic remote sensing will enter into a new phase in which hyperspectral data becomes readily accessible all over the world. JOGMEC is conducting a research and development program on effective use of geologic remote sensing for mineral exploration. Considering high level of demand to rare earth element (REE) resources, JOGMEC accelerates not only REE resource exploration in Ex-China, but also development of regional mapping tools to identify REE bearing minerals remotely. This paper briefly reviews reflectance spectra of REE bearing minerals and introduces JOGMEC's approaches to the development of potential exploration tools.

On this paper, wavelet analysis has been used for internal wave detection in ERS SAR and ASTER images data over Tsushima strait, southwest of Japan, during 1993-2004 period. Various wavelet transforms, such as Haar wavelet, Symlet wavelet, Coif wavelet, Daubechies wavelet, and Discreet Meyer wavelet, are tested comparably with different level of synthesize image on horizontal, diagonal, and vertical detail, and approximation to study the internal wave characteristic in image. Internal wave features were detected as elongated pattern in image with higher wavelet coefficient (>36) than sea surface (litlle than 10) on horizontal and vertical detail coefficient of image transforms at level 2-5. The decomposition image shows the tendency that the decomposition of internal wave feature using wavelet transform tends to follow the wavelet function. This may reduced the height of leading wave. Smoother result of internal wave shape can be formed using higher scale resolution of image and higher number of vanishing moments such as Daubechies waveletdb5, Symlet wavelet-sym5, and Discrete Meyer wavelet. The compactly supported wavelet function with orthogonal basis with scale function and FIR filter, such as discrete Meyer function is proposed for smoothness of feature, space save coding, and to avoid depashing in image. So far, the detection processes were performed well on the internal waves data that occurred at north coast off Kitakyushu and NW/W/SW/E coast off Tsushima Island on June to September period whose lengths were detected between 6-28 km and wavelength between 120m-1.28km. The directions of internal wave propagation were varied between NW-SW at eastern channel and N-SW at western channel of Tsushima Strait. Keywords: wavelet analysis, SAR image, optical image, internal wave.

In this paper, wavelet transform based on dyadic scales and spatial location have been used for internal wave detection in SAR image. It performed by using multi resolution analysis of image for feature detection and image enhancement. Wavelet transform uses local analysis to analyze a shorter region in image in time and scale data allows precise information than time and frequency region analysis such as Fourier analysis. Internal wave is observed in SAR image by effect of Bragg scattering process in sea surface that represents the meso-scale feature of sea processes. SAR image data is used considering to the effectiveness of large scales area monitoring on near real time data. Internal waves were observed in ERS-1 per 2 SAR images data over Lombok Strait during 1996-2001 period using 2D Symlet analysis for the symmetric extension of data at the image boundaries, to prevent discontinuities by a periodic wrapping of data in fast algorithm and space-saving code. Lombok Strait is chosen as study area because this strait is a major passage of the flow from Pacific Ocean to Indonesian seas (ARLINDO) and passage of Indian Ocean Kelvin wave to Makassar Strait. Keyword: SAR image, internal wave, wavelet analysis.

The multi-parametric data observed by the Synthetic Aperture Radar (SAR) and the Moderate Image Scanning Radiometer (MODIS) were applied to analyze the water distribution in the Philippine Archipelago to build a new radar imaging model. The SAR provides information on the surface structure of the water affected by various phenomena such as currents, internal waves, swells, surface winds, rain falls, natural films, and so on. One difficult parameter among them is the natural film, which exhibits a damping effect to the surface roughness from breaking waves to capillary ones. The chlorophyll-a concentration observed by satellite sensors such as MODIS provide estimates of the standing stock of phytoplankton, which is considered as the parameter estimating the standing stock of zooplankton. The standing stocks of phytoplankton and zooplankton could be a proportional parameter to the amount of the natural film. In this study, a frequency dependent multi-parametric equation was proposed to rebuild the surface roughness with various parameters in the spectrum domain. Possible validation study was conducted with the relationship between the sum of power spectrum for certain frequency range with chlorophyll-a concentration on the Mindanao Sea and the Surigao Strait.

Wavelet transform has been applied for multi resolution analysis of oceanic feature in ERS1/2 SAR and ASTER image data over the Tsushima Strait. Various wavelet transforms, e.g. Haar, Daubechies, Symlet, Coif, Biorthogonal, and Meyer wavelet, have been tested comparably with different level of synthesized image on horizontal, diagonal, and vertical detail, and approximation to study the internal wave characteristic in image. The results show that higher scale processing of image and higher number of vanishing moments of wavelet function such as Coiflet wavelet, coif5, Daubechies wavelet, db5, Symlet wavelet, sym8, and Discrete Meyer wavelet, are proposed for smoother wave crest. The best result of detection is performed by Discrete Meyer wavelet transform, which adapts FIR filter, orthogonal and biorthogonal basis. Thus, it liable for smoothness of feature, space save coding and avoid dephasing in image.

This paper studies the effect of internal wave in the Lombok Strait to chlorophyll distribution in the surrounded areas using ERS SAR, ASTER, SeaWiFS and AVHRR-NOAA images data during 1996-2004 periods. The observation results shows that the internal waves were propagated to the south and the north of strait and mostly occurred during transitional season from dry to wet and wet season (rainy season) between September to December when the layers are strongly stratified. Wavelet transform of image using Meyer wavelet analysis is applied for internal wave detection in ERS SAR and ASTER images, for symmetric extension of data at the image boundaries, to prevent discontinuities by a periodic wrapping of data in fast algorithm and space-saving code. Internal wave created elongated pattern in detail and approximation of image from level 2 to 5 and retained value between 2-4.59 times compared to sea surface, provided accuracy in classification over than 80%. In segmentation process, the Canny edge detector is applied on the approximation image at level two to derive internal wave signature in image. The proposed method can extract the internal wave signature, maintain the continuity of crest line while reduce small strikes from noise. The segmentation result, i.e. the length between crest and trough, is used to compute the internal wave induced current using Korteweg-de Vries (KdV) equation. On ERS SAR data contains surface signature of internal wave (2001/8/20), we calculated that internal wave propagation speed was 1.2 m/s and internal wave induced current was 0.56 m/s, respectively. From the observation of ERS SAR and SeaWiFS images data, we found out that the distribution of maximum chlorophyll area at southern coastline off Bali Island when strong internal wave induced current occurred in south of the Lombok Strait was distributed further to westward, i.e. from 9.25°-10.25°LS, 115°-116.25°SE to 8.8°-10.7°LS, 114.5°-116°SE, and surface chlorophyll concentration near coastal area, i.e. area 8.8°-9.25° LS, 114.5°-115°SE, increased. The preliminary result of this study concludes that the internal waves presumably affect chlorophyll distribution to westward (from 9.25°-10.25°LS, 115°-116.25°SE to 8.8°-10.7°LS, 114.5°-116°SE) in the south coast off Bali Island and increase surface chlorophyll concentration near coastal area (8.8°-9.25° LS, 114.5°-115°SE).

We observed sea surface signature of internal waves in ERS SAR and ASTER image over southwest of Japan during 193-2004 period. Wavelet transform has been applied for multi resolution of internal wave detection in image. Proposed method based on Meyer wavelet and Canny edge detector has been useful to delineate internal wave feature in ERS SAR and ASTER image, maintain the continuity of crest line while reduce small strikes from noise. Internal wave features were detected as elongated pattern in image with higher wavelet coefficient (>36) than sea surface (