Abstract: Method of predicting paraffin deposition risks during hydrocarbon production and/or transport, applicable at an early reservoir characterization and production stage. It comprises forming a database characterizing the hydrocarbons in the formation, including density data acquired by well logging and data obtained by analysis of rock samples taken from the reservoir formation, an analytical representation of the hydrocarbons by a limited number of pseudo-components comprising each certain hydrocarbon classes with a definition of their respective mass fractions and application of data of said base to a thermodynamic model for determining one or more parameters indicative of the crystallization conditions such as, for example, the starting crystallization temperature, the solid fraction that precipitates when the temperatures falls below this starting crystallization temperature, etc. Applications: hydrocarbon production field valuation.

Abstract: Method of predicting paraffin deposition risks during hydrocarbon production and/or transport, applicable at an early reservoir characterization and production stage.

Abstract: The invention provides a method for determining the organic matter content of sedimentary rocks from data recorded in the well by at least two well-logging probes measuring different parameters. Two probes are chosen, one for responding in the same direction ot a variation of the water and organic matter content of the rocks, the other for responding very differently to a variation of one or other of these same components, and both so that the iso-organic matter content lines in a three pole diagram are substantially merged whether the third pole is the water pole or the clay pole. The position of the line I(0%) is determined experimentally and the organic matter content is derived therefrom corresponding to each pair of values of the parameters measured in the well. In a diagram where the parameters used depend, for example, on the transit time of sound in the rock and on the electric resistivity of the formations, the iso-content lines form a family of parallel lines.