This study is concerned with the 2D modelling of the mineralised units of the uranium deposit at the Nord-Taza Satellite prospect (Arlit, Northern Niger). The Nord-Taza Satellite prospect, operated by Aïr Mines Company (SOMAÏR), is an integral part of the uranium deposits in the Arlit sector, which are hosted by sandstones of Carboniferous age and deposited in a fluvio-deltaic environment. The methodological approach adopted consists of correlating the data obtained from development drilling and facing surveys using modelling software such as Surpac and Sermine. The minerals present include orthoclase, quartz, biotite, zircon, monazite and apatite. The lithological analysis showed that the study area is characterised by coarse sandstones with microconglomeratic tendencies, argillites and finely consolidated sandstones. These facies, referred to respectively as Unit 1 (U1), Unit 2 (U2) and Unit 3 (U3) of the Tarât, are the host formations for the uranium mineralisation in the study area. Correlation of data from boreholes and face surveys has shown that high uranium grades are found in the reduced sandstones of units U1 and U3, while low grades are found in the mudstones of unit U2. Information obtained from the Surpac software showed that uranium mineralisation is oriented in a north-south direction and is more concentrated on the western flank of the study area near the Arlit normal fault-flexure. The 2D model produced using the Sermine software showed that U1 has stratiform mineralisation, U2 has discontinuous or isolated lens mineralisation and U3 has chenalising lens mineralisation. The U4 or Madaouéla unit is not mineralised in the Nord-Taza Satellite prospect.

Most of Niger's oil exploration and production activities take place in the Termit Basin. The Paleogene Sokor1 Formation, an important exploration target in the Termit Basin, is a typical sandstone hydrocarbon reservoir. The research presented in this paper used core, water samples and wireline logs, collected in the Dibeilla prospect to determine factors impacting the occurrence of low resistivity oil/gas reservoirs during their diagenetic processes to avoid exploration extra-cost and to recover the total reserves. Cores were analyzed based on thin sections, scanning electron microscopy, X-ray diffraction, and capillary pressure test. Wireline logs were analyzed using the Combined Log Pattern technique. The distributions of all potential influencing factors on porosity and permeability were quantified, making it possible to assess the influence of all potential controls on resistivity logs reading regarding to the fluid type. Diagenetic processes in the Sokor1 oil/gas reservoirs with low resistivity include cementation and dissolution, apart from mechanical compaction. Authigenic clay minerals, pyrite and siderite that account for resistivity controlling factors, occur as pore-filling and pore-lining cements, increase the reservoir conductivity. Sedimentary facies with fine lithological features resulted from relatively weak hydrodynamic deposition conditions induced by irreducible water and dual pore-structure system are the primary causes related to resistivity reduction in oil/gas saturated reservoirs. The low resistivity oil/gas reservoirs identified are the result of mix factors. Results demonstrate the robust application of combining diagenesis and Combined Log Pattern in predicting favorable reservoirs, useful in reducing exploration risk in undrilled areas and oilfields with similar geologic settings.