This week was busied time for me and all my team at office. But write for this posting is the most exciting thing.
Hhmm, Geology. Do you know it?..Yup it’s all about mineral, stratigraphy, rock, volcanology, fold, fractures, fault, dip and strike, slicken, and others.
Remote sensing now, could help geologist much better especially for geological mapping. All geological maps contain an image that describes the spatial distribution of the lithologies, symbols that describe the structural relationships (folds and faults), and a stratigraphic column that describes the temporal relationships of lithologies.
Methods for that study are; First, the identification of lithologic contacts, and their differentiation by spectral signatures is complicated by mechanical break down of the lithologies into boulder fields, which do not provide a homogeneous target for remote sensing. Different approaches to image segmentation include spectral signature based MNF and edge detection algorithms. Second, hyperspectral imagery records the spectral signature of weathered surfaces of the various lithologies. Identification of a specific lithotype is rarely defined by reference to library spectra but more commonly field acquired characteristic spectra. Third, establishing the stratigraphic and structural relationships of rock units requires some knowledge of their three-dimensional distribution. Where available topographic data provides the three-dimensional constraint and often assists in the definition of lithological contacts.
Geologists have used aerial photographs for decades to serve as databases from which they can do the following:
1. Pick out rock units (stratigraphy)
2. Study the expression and modes of the origin of landforms (geomorphology)
3. Determine the structural arrangements of disturbed strata (folds and faults)
4. Evaluate dynamic changes from natural events (e.g., floods; volcanic eruptions)
5. Seek surface clues (such as alteration and other signs of mineralization) to subsurface deposits of ore minerals, oil and gas, and groundwater.
6. Function as a visual base on which a geologic map is drawn either directly or on a transparent overlay.
With the advent of space imagery, geoscientists now can extend that use in three important ways:
1) The advantage of large area or synoptic coverage allows them to examine in single scenes (or in mosaics) the geological portrayal of Earth on a regional basis
2) The ability to analyze multispectral bands quantitatively in terms of numbers (DNs) permits them to apply special computer processing routines to discern and enhance certain compositional properties of Earth materials
3) The capability of merging different types of remote sensing products (e.g., reflectance images with radar or with thermal imagery) or combining these with topographic elevation data and with other kinds of information bases (e.g., thematic maps; geophysical measurements and chemical sampling surveys) enables new solutions to determining interrelations among various natural properties of earth phenomena.
MAJALENGKA GEOLOGICAL MAP.
I promise to wildan to make him Majalengka Geological Map. Wildan is a student from Geological Engineering, ITB, Bandung.
Data used for this map come from PUSLITBANG GEOLOGI.
Majalengka is part of Bogor-Basin Geologic Area (back-arc-basin), these basin has characteristic gravity mass flow turbidity deposition, formed at first Miosen. Deposition become younger to North and related to fold-thrust beld pattern to North-East. This stripe is a connecting structure from West, around Purwakarta to the East aroung Bumiayu.