Abstract The Oued Gueniche plain is located in the northeastern Tunisia. It is a part of the Bizerte Neogene molassic basin, developed at the front of the Alpine chain (The Maghrebides). The subsurface structure of this area is not enough explored and was subject of controversial interpretations. Gravimetric and seismic data acquired in the northeast of Tunisia were used to study and update the structural scheme especially of the plain of Oued Gueniche (the geometric configuration of its subsoil, the different stages of its formation and its relation with the surrounding folds). A total number of 664 gravity measurements were used to define the density distributions below the surface in the study area. The complete Bouguer gravity anomaly was performed with a reduction density of 2.4 g/cm3. Bouguer anomalies ranging from 9.5 to 34.8 mGal were observed in the study area, high anomalies coincide with the Oued Gueniche plain in the northwest while weak anomalies are observed on the southwest side of the study area. The main NE-SW anomalies are superposed to the geological structures. The power spectrum of gravity data shows that the calculated average depth to the top of regional gravity sources is approximately 4 km while that of local (or residual) sources is approximately 0.6 km. The techniques for locating the limits of anomalous structures and estimating their depths (tilt derivative (TDR), Euler deconvolution (ED) and analytical signal (AS)) were applied to the Bouguer anomaly map of the study zone to further specify the underground geological characteristics. The maxima of the horizontal gradient magnitudes (MGH) of Bouguer anomalies upward continuated at different altitudes revealed several lineaments having NE-SW and E-W directions. These trends coincide with known surface structural trends. A three-dimensional (3D) inversion model of gravity data has been developed for the Oued Gueniche plain in order to follow the distribution of densities. In addition, the interpretation of seismic profiles shows that the central part of this plain is also marked by the diapirism of Triassic rocks. The combination of these results with those of the surface (geology and shallow hydrogeological boreholes) has led us to propose a kinematic model of the Bizerte region since the Middle Miocene and to update of the structural scheme. Then, the NE-SW major faults and the NW-SE secondary ones have controlled the paleogeography and the structuration of the study area.

中文翻译：

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坍塌的 Oued Gueniche 平原及其周围褶皱（突尼斯东北部比塞大的新近系磨拉石盆地）的成因和结构排列：重力数据的见解

摘要 Oued Gueniche 平原位于突尼斯东北部。它是比塞大新近纪糖浆盆地的一部分，在阿尔卑斯山链（马格里比德斯）的前端开发。该地区的地下结构没有得到足够的探索，并且是有争议的解释的主题。在突尼斯东北部获得的重力和地震数据用于研究和更新结构方案，特别是 Oued Gueniche 平原的结构方案（其底土的几何构造、其形成的不同阶段及其与周围褶皱的关系）。总共使用了 664 次重力测量来定义研究区域地表以下的密度分布。完整的布格重力异常以 2.4 g/cm3 的还原密度进行。布格异常值范围从 9.5 到 34。研究区观测到 8 mGal，高距平与西北部的 Oued Gueniche 平原重合，而在研究区西南侧观测到弱距平。主要的 NE-SW 异常叠加在地质构造上。重力数据功率谱显示，计算到区域重力源顶部的平均深度约为4 km，而局部（或残余）源的平均深度约为0.6 km。将异常构造边界定位及深度估算技术（倾斜导数（TDR）、欧拉反卷积（ED）和解析信号（AS））应用于研究区布格异常图，进一步明确地下地质特征. 布格异常的水平梯度震级（MGH）的最大值在不同高度继续向上，揭示了几条具有 NE-SW 和 EW 方向的线条。这些趋势与已知的表面结构趋势一致。为了跟踪密度分布，已经为 Oued Gueniche 平原开发了重力数据的三维 (3D) 反演模型。此外，地震剖面的解释表明，该平原的中部也以三叠纪岩石底辟为标志。这些结果与地表（地质和浅水地质钻孔）的结果相结合，使我们提出了自中中新世以来比塞大地区的运动学模型，并更新了结构方案。然后，