The Gulf of İzmit is a critical basin in assessment of the kinematics of the North Anatolian Fault (NAF) at the eastern margin of the Sea of Marmara. The available seismic reflection data do not provide sufficient and clear evidences to outline the deeper structures because of limited penetration. In agreement with the known main tectonic elements from available seismic data and multi-beam bathymetry, new magnetic data gathered within the scope of this study show E–W trending anomalies and permit us to outline satisfactorily the deeper tectonic setting of the gulf region. The northern strand of the NAF can be evidently correlated with the maxima on the magnetic profiles, implying a significant thinning in the crust along the weakness zone placed between the Istanbul Zone and Karakaya Complex. Such a tectonic structure must have been formed as parallel transform strike-slip pressure, which is different from the characteristic negative-flower structure observed at the East Marmara trough. This pattern occurs in a relatively narrow zone, because it has been superimposed on a paleo-tectonic lineament.

中文翻译：

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从海洋磁异常推断伊兹密特湾北安那托利亚断层的北段

伊兹密特湾是评估马尔马拉海东缘北安那托利亚断层（NAF）运动学的重要盆地。由于穿透力有限，现有的地震反射数据没有提供足够清晰的证据来勾勒出深层结构的轮廓。与现有地震数据和多波束测深法中已知的主要构造要素相一致，在本研究范围内收集的新磁数据显示了E-W趋势异常，使我们能够令人满意地勾勒出海湾地区更深的构造背景。NAF的北链显然与磁剖面上的最大值相关，这意味着沿着位于伊斯坦布尔区和卡拉卡亚复合体之间的薄弱带的地壳明显变薄。这样的构造结构必须形成为平行变换的走滑压力，这与在东马尔马拉海槽观察到的特征性负花结构不同。这种模式出现在一个相对狭窄的区域，因为它已经叠加在古构造的线条上。