Investigation of Kouhestak- Karian Coastline changes using GISStudy area The study area is part of coastline of Hormozgan province in the Persian Gulf and it lies between longitude 56º 52´ – 57º 5´ and Latitude 26º 45´ - 27º and is located in North of Hormuz strait, Southern Iran (figure 1). The coastline of Iran along the Persian Gulf has a total length about 2440 kilometers. Whereas the Hormozgan province is a coastal region in southern Iran with 1100 kilometers coastlines in Persian Gulf and Oman sea coasts.  Figure 1. Location map of the study area Investigation of Coastline Changes on Short period (26 years) This research focuses on coastal zone and is based on aerial photographs and supported by topographical maps, Aster Image satellite (2001) and GIS Applications. The image processing was to prepare a false color composite Aster Image of bands 321 which emphasize geology, irrigated area, land use and shoreline. The main part of study area is covered by Quaternary Formations and Pleistocene conglomerate deposited in the basin. In this research two series of aerial photographs (1967&1993) and several steps were used to prepared final maps as follows: 1). Aerial photos has been scanning with gray scale shape by 300 dpi and mosaics for two different years using Adob Photoshop software by jpg format and were carefully checked and corrected where possible and created a false color composite Aster Image 3 2 1 bands (fig.2) for new investigation and filed work. 2). Digital photographs have been converted into ILWIS GIS package and georeferenced using digital topographic map (1: 50000) and standard ILWIS image to image method. The most important Coordinate systems useable in this step are LatLon and UTM Coordinate systems. Due to the accurate necessary of area was used UTM Coordinate System. 3). Delineation of coastal zone units by visual interpretation and were digitized on screen (on screen digitizing method) using landform concept of each coastal units (boundary of landform units) for two different years (1967 and 1993) and preparing maps of Coastal landforms for each year (Fig.3) using ArcGIS Program.  Fig.2. Aerial photos of study area (1967 & 1993) and FCC of bands 321(RGB) of Aster Image (2001) The coastal landform of the study area can be grouped as follows (see Fig. 3).
4- Raster polygon maps with 0.5 * 0.5 meter pixel size were generated using polygon to raster option for each year (1967 & 1993). The output raster map always uses the same domain as the input polygon map. The secondary step in raster operation was to prepare a cross map 1967 and 1993 by standard ILWIS cross option. These combinations give an output cross map and a cross table.  Fig.3. Polygon Maps of Coastal landform for each year 5. The Final step was prepared map of coastline area changes (Fig. 4) using cross table and attribute map operation and prepared final map of coastline area changes by ArcGIS Program (Fig. 4).  Fig.4. Coastline changes map of the study area Investigation of Coastline Changes on long period (Quaternary) The investigation of paleoshorlines is based on field observations, fossil sampling and supported by aerial photographs (1993), Aster image (2001), topographical map (1:50.000) and GIS applications. The image processing was to prepare a FCC of bands 321 (RGB) of Aster image, for preliminary investigations and prepare paleoshorlines map. According to aerial photographs and image satellite several paleoshorlines were shown in the study area that results of regression final of sea water in the Holocene. In this part of research several step were used to prepared final map and determination of coasts uplift rates as follows: 1) Prepared paleoshorline map using aerial photographs (1993) and update by Aster image (2001) and supported with field work (Fig.5). |