Abstract: A new class of multifunctional tracers has been synthesised for use in the oil industry, specifically during waterflooding operations. They are used either in a traditional way (i.e., mapping the connections of oilfield selections) or to provide information on important physical-chemical parameters (such as oil content, temperature and rock permeability) useful for optimizing the oilfield management and subsequent improvement/increase in oil extraction. The multifunctional tracers have a polymer chain having a plurality of units different from one another and recurring along the chain and having respective specific functionalities.

Abstract: A fluid for controlling the permeability of a subterranean formation having an aqueous solution of at least one thermo-responsive polymer with block structure A-B-A?, wherein A and A?, the same as or different from one another, each represent a thermo-responsive oligomer group, and B is an oligomer group having n repeat units, the same as or different from one another. At least one of the repeat units has a solubility of the corresponding monomer, in water at 20° C., equal to or greater than 120 g/l, and n is a whole number within the range 30-1000. The fluid is also used in a method for controlling the permeability of a subterranean formation.

Abstract: A method for predicting the properties of crude oils by the application of neural networks articulated in phases and characterized by determining the T2 NMR relaxation curve of an unknown crude oil and converting it to a logarithmic relaxation curve; selecting the values of the logarithmic relaxation curve lying on a characterization grid; entering the selected values as input data for a multilayer neural network of the back propagation type, trained and optimized by means of genetic algorithms; predicting, by means of the trained and optimized neural network, the physico-chemical factors of the unknown crude oil. The method comprises a training and optimization process of the multilayer neural network of the back propagation type. The method thus defined allows the most representative physico-chemical factors of crude oils to be predicted rapidly and without onerous laboratory structures, or alternatively the distillation curve of crude oils with an acceptable approximation degree.

Abstract: A process is described for reducing the production of water in oil wells which comprises the injection into the formation around the well of an aqueous solution of one or more polymers selected from those having general formula (I), wherein: n ranges from 0.70 to 0.98; m ranges from 0.30 to 0.02; n+m=1; X1 and X2, the same or different, are selected from H and CH3; R1, R2, R3, the same or different, are selected from C1–C10 monofunctional hydrocarbyl groups; and x ranges from 2 to 5.

Abstract: A process is described for reducing the production of water in oil wells which comprises the injection into the formation around the well of an aqueous solution of one or more polymers selected from those having general formula (1) [] wherein: n ranges from 0.70 to 0.98; m ranges from 0.30 to 0.02; n+m=1; X1 and X2, the same or different, are selected from H an CH3; R1, R2, R3, the same or different, are selected from C1-C10 monofunctional hydrocarbyl groups; x ranges from 2 to 5.

Abstract: A process is described for reducing the production of water in oil wells, with temperatures of up to (90° C.), which comprises the injection in the formation around the well of an aqueous solution of one or more polymers selected from those having general formula (I) wherein: n ranges from (0.40) to (0.70), preferably from (0.5) to (0.65); m ranges from (0.15) to (0.65), preferably from (0.3) to (0.5); p ranges from (0.02) to (0.20), preferably from (0.05) to (0.

Abstract: A process is described for reducing the production of water in oil wells which comprises the injection into the formation around the well of an aqueous solution of one or more polymers selected from those having general formula (1) [ ] wherein: n ranges from 0.70 to 0.98; m ranges from 0.30 to 0.02; n+m=1; X1 and X2, the same or different, are selected from H an CH3; R1, R2, R3, the same or different, are selected from C1-C10 monofunctional hydrocarbyl groups; x ranges from 2 to 5.

Abstract: A process is described for reducing the production of water in oil wells, with temperatures of up to (90° C.), which comprises the injection in the formation around the well of an aqueous solution of one or more polymers selected from those having general formula (I) wherein: n ranges from (0.40) to (0.70), preferably from (0.5) to (0.65); m ranges from (0.15) to (0.65), preferably from (0.3) to (0.5); p ranges from (0.02) to (0.20), preferably from (0.05) to (0.10); n+m+p=1; x1 is selected from H and CH3; R1, R2 the same or different, are selected from C1-C10 monofunctional hydrocarbyl groups.