Sonatrach

About: Sonatrach is a company organization based out in Algiers, Algeria. It is known for research contribution in the topics: Hydraulic fracturing & Structural basin. The organization has 460 authors who have published 494 publications receiving 6339 citations. The organization is also known as: Sonatrach SPA.

Multidisciplinary Approach for Unconventional Reservoirs Characterisation by Integrating Wireline Openhole Logging Techniques – Electric and Sonic to Formation Testing

Abstract: This paper has an objective of identifying the nature of formation fluid from an extreme tight fractured reservoir. A good understanding of petrophysical properties of the reservoir rock as well as the fluid it contains constitutes a real challenge for tight reservoirs, that are the most common unconventional sources of hydrocarbons. The front-line characterization mean is the Wireline logging which comes directly after drilling the well or while drilling, knowing that for low to extreme low porosity-permeability reservoirs any attempt of conventional well testing will not bring any added value not rather than a confirmation of reservoir tightness. A tailored workflow was adopted to design the most appropriate formation testing module, select the best depths for fluid sampling, and distinguish hydrocarbon from water bearing intervals. This workflow involves ultra-sonic and Electric Borehole Images in combination with Sonic Scanner for natural fractures detection, localization and characterization, integrating Dielectric recording and processing for petrophysical evaluation, then Formation Testing was carried out for fluid identification and sampling. The use of borehole electric and sonic imager coupled with advanced sonic acquisition helped not only to identify the natural fractures depths, but also the nature of these fractures. This integration was used for selecting the sampling station. Successful fluid sampling was carried out in 4 different depths (2 gas and 2 water), then a dielectric measurement was integrated to map the continuity of the water zone and narrow the uncertainty on fluid contact. This novel multidisciplinary approach that was adopted, integrates answer products from different domains to enable the interpreter, (the reservoir engineer, the geologist, and the Petrophysicist) to better understand and characterize the reservoir, toward a good reserve’s evaluation and appropriate development plan.

Séquence de dépôts binaire et discontinuités associées - Exemple des séries crétacé-tertiaire du bassin Maghrébin et de l’Atlas saharien, Algérie du Nord

Abstract: Une sequence de depots binaire a ete elaboree a partir d’observations de terrain. Elle s’applique a differentes echelles et a differents milieux de depots. La sequence binaire est composee de deux sequences. Chacune d’elles est subdivisee en deux cycles. Les cycles inferieurs representent les 3/5e en duree et les cycles superieurs les 2/5e . Au total, cela fait quatre cycles. Dans le detail, cette sequence binaire comprend dix termes de facies delimites par dix discontinuites dont quatre sont importantes. Ces dernieres delimitent les quatre cycles. On distingue deux « maximum flooding surface » (m.f.s.) au centre des deux cycles superieurs.