Tez özetleri Astronomi ve Uzay Bilimleri Anabilim Dalı

Determination Of Horizantal And Vertical Rotations In Biga Peninsula By Paleomagnetic Data

The study area is located in the Biga peninsula. The area is covered with Late-Middle Miocene aged Balabanlı volcanic unit. To determine the horizantal and vertical rotations during this period, paleomagnetic samples were collected from 40 sites. 32 sites yielded reliable remanent magnetization directions.

We have applied conglomerate test at one site to test if the area was exposed to a secondary magnetization. According to conglomerate test the volcanic rocks in the area did not gain a secondary magnetization. To determine the magnetic properties of the sites we applied detailed rock magnetic mesaurements such as hysteresis loops, Curie temperature curves and low temperature experiments. In addition to rock magnetic studies, XRD measurements were performed to determine the magnetic mineral content in the rocks studied. According to the rock magnetic studies, 38 sites are in the Pseudo Single Domain range. In most of the sites magnetite is the main magnetic mineral. Thermal demagnetization had been applied to all of the samples to gain the magnetization directions. Statistic parameters are also reliable according to thermal demagnetization steps.

Declinations show 49^o clockwise rotations from younger formations to older ones. This rotation is explained by the movement of Kazdağ core complex from north to south. The present trend of the Kazdağ core complex and the results of this study is consistent. Moreover, younger volcanics in the area is effected by the rotations along N-S extending faults.