Distribution of Natural Radioactivity from 40K\text{}^{40}K Radioelement in Volcanics of Sandıklı-Şuhut (Afyon) Area

Many radioactive elements have existed when the Earth had appeared and the long living of them are still present. One of the most important of these radioactive elements is $\text{}^{40}K$. It makes about 0.012% of total content of K, widely represented in many different rocks. In this study the distribution of the natural $\text{}^{40}K$ radioelement in the volcanics of the south part of Afyon was investigated. Gamma-ray spectrometer was used for in-situ measurements of this radioelement concentration. Studied area has covered approximately 1800 km². In-situ measurements were performed at 1390 different locations in this field. Data for each measurement was gathered during 3 min. The map of the ^{40}K element distribution in the studied area was produced. The high values of $\text{}^{40}K$, according to this map, were obtained in the areas of the alteration zones, between Sandıklı and Şuhut in the studied area

Late Holocene sea level change along the coast of Fethiye Gulf in southwestern Turkey

In the Fethiye Gulf on the southwest coast of Turkey, several submerged archaeological sites provide useful data about relative sea level changes since the Byzantine period. The current elevations of contemporary archaeological structures were measured to determine the amount of relative sea level change. The archaeological sea level markers in this seismically active region provide new data about the amount and period of relative sea level rise. Taking into consideration the time of the last use of the structures, instead of their time of construction, three different rates of vertical land movement of 2.18 +/- 0.3, 2.96 +/- 0.3, and 3.29 +/- 0.5 mm/yr were estimated. These data indicate that tectonic activity differs from region to region, most likely related to local normal faults in the gulf. Recent earthquakes have confirmed active seismicity in this area. These results demonstrate that the changing sea levels in the Fethiye Gulf have been strongly influenced by vertical tectonic movement over the last 1,400 years. Results also contribute to studies of future coastal changes in the Fethiye Gulf and its surroundings