In Berkine Basin, the Siegenian stage is constituted by clayey sandstones and it contains several reservoir levels especially in the perimeter of Zemlet El Arbi, where the sandstone levels can reach 30 m of thickness. The Siegenian reservoir shows a tidal deposit environment, it is located at depths greater than 3200 m, its average thickness is 200 m in the south and it decreases to 30 m because it is strongly affected by Hercynian orogeny mainly in the northwest of the studied area. Petrographic and X-ray diffraction studies indicate the presence of authigenic chlorite, which is the most important cement in Siegenian sandstones. Chlorite appears in different forms: grain coating, pore lining, pore filling and rarely in the form of oolite. It often has a great impact on petrophysical reservoir qualities by inhibiting authigenic quartz overgrowth in porous space and preserving porosity. Other diagenetic phenomena observed are mechanical compaction, alteration and dissolution of feldspars and biotite, precipitation of clay minerals (smectite, berthierine, chlorite, kaolinite and illite) and precipitation of secondary silica, carbonates, pyrite and haematite.

在Berkine盆地，Siegenian阶段是由粘土质砂岩构成的，它包含多个储层，特别是在Zemlet El Arbi周边，那里的砂岩厚度可以达到30 m。Siegenian水库显示出潮汐沉积环境，它位于大于3200 m的深度处，其平均厚度在南部为200 m，并减少到30 m，因为它主要受研究区域西北部海西造山运动的强烈影响。岩石学和X射线衍射研究表明，自生绿泥石的存在，这是锡根尼砂岩中最重要的水泥。亚氯酸盐以不同形式出现：颗粒涂层，孔隙衬里，孔隙填充，很少以软沸石形式存在。它通常通过抑制多孔空间中自生石英的过度生长并保持孔隙度，而对岩石物理储层的质量产生重大影响。观察到的其他成岩现象是机械压实，长石和黑云母的蚀变和溶解，粘土矿物（蒙脱石，黄铁碱，绿泥石，高岭石和伊利石）的沉淀以及次生二氧化硅，碳酸盐，黄铁矿和赤铁矿的沉淀。