Investigation of Kouhestak- Karian Coastline changes using GIS2) Paleoshorline survey and fossil sampling In order to sample points and direction of survey were distinguished on aerial photographs and map and then a long transect about 6 km, from oldest paleoshorline (Fig. 7) toward sea and prepared a cross section of survey direction. Several transverse dunes or paleoshorlines at various elevations could also be seen from near sea to about 6 km far from them in the study area. The fossil sampling was done from oldest to newer paleoshorlins along of survey direction (24 samples). Two samples were selected (S4 & S24) for radiocarbon test. Location and accurate elevations of 2 points (S4 & S24) were measured using DGPS. 3- Correlation and Dating of former Coastlines Two fossil samples were tested by 14C method at Jaber-Ebn-Hian laboratory in Iran (S4 & S24). The results of absolute age determination of samples selected were shown in table 1 and calculated uplift and regression rate of coast.
 To comparison between units of coastline changes map (Fig.4), can shows, that coastal accretion area is more than the coastal erosion area. The coastal accretion areas are located in eastern part of the study area where wind sediments are exposed and the mouth of river with more sediment. The geological and hydrodynamic factors play an important role in the transportation and movement of sediments. In the western and eastern parts of Zarani river important sedimentary process is erosion, particularly which waves are dominant (wave dominated shorelines). However, due to about 30 years time interval, the results can be based for regional planning and coastal constructions by 50 years return period in the study area. The use of aerial photographs with digital format and GIS coverage’s for mapping Coastal provides a number advantages over conventional aerial photographs interpretation and other data including timeliness, synopticy, and reduced costs. The investigation of coastline behavior can be beneficial for hazard reduction. Based on superficial and vertical coastal changes rates of study area (fig.8) and dating of former coastlines by 14C method (table 1) the regression rate can be calculate relatively. Sediment yield recharge, wind sediments transport and coastal profile slope are influences on dominate coastal processes in the study area and can be change in place by place. According to distance of paleishorlines from recent coastline and age of them (table 1), coastline regression rates is 0.27 m/year and 1.17 m/year respectively S4 and S24 samples. Whereas uplift rate is 0.6 mm/year duration between 3900 to 1850 years ago that indicated of increasing of sediment yield recharge, inland upward or sea level downward in a 2050 years period. Important results of sea level changes are formation of coastal sedimentary sequences in Quaternary time. Coastal sedimentary sequences in the study area are shown retrogressive coastline and respectively from base to up including Plioplistocene conglomerates, high and low level alluvium terraces, sand ridge that are components of wave dominate deltas, tidal flat, supra tidal, river alluvial deposits considered: river channel deposits, river bar deposits and flood plains and evaporate deposits (sabkha).  Fig. 8: superficial and vertical coastal changes rates and amounts in the study area Acknowledge We acknowledge financial support for the research project of An Investigation of Hormozgan province Coastline Changes from Agricultural and Natural Recourses Research Center of Hormozgan province and Soil Conservation and Watershed Management Center. References
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