Field Of Oil Exploration Research Articles

Improved and Standardized Methodology for Oil Spill Fingerprinting

The existing Nordtest methodology for oil spill Identification has over the past 10 years formed an important “platform” for solving oil spill identification cases both in the Scandinavian countries as well as other countries in Europe, the USA and Canada. “Revision of the Nordtest Methodology for Oil Spill Identification” is a cooperative project between the National Oil Spill Identification laboratories in Norway, Sweden, Finland, Denmark and the Battelle Memorial Institute (Duxbury) in the USA. The goals of the project are: (1) to refine the existing Nordtest methodology into a technically more robust and defensible oil spill identification methodology with focus on determination of quantitative diagnostic indices (ratios) and (2) to adjust the revised Nordtest methodology into guidelines for the European Committee for Standardization (CEN). This paper presents the recommended methodology for the analytical oil spill identification part. The sampling techniques and handling of oil samples and background (reference) samples prior to their arrival at the environmental forensic laboratory is not covered in this paper. The recommended methodology approach is a result of documented analytical improvements and a more quantitative treatment of analytical data from gas chromatographic-flame ionization detector (GC/FID) and gas chromatographic-mass spectrometer methods (GC/MS-SIM) and the operational experiences over past few years among the participating forensic laboratories. The experience and literature in the field of oil exploration and production geochemistry have also played an important role for the recommended methodology. The results from a recent Round Robin test carried out among 12 laboratories using this new methodology are presented in a separate paper in this issue (8).

我が国原油自主開発の未来像

Now, Japanese oil exploration companies face an unprecedented crisis. To begin with the abolishment of Japan National Oil Corporation (JNOC) which played the most important role in the oil exploration activities in foreign countries, there are many problems such as the lost of oil development interest in Saudi Arabia and the accumulated loss of some Japanese oil companies. On the other hand, the dependence on Middle East in the field of oil import of Japan is approaching the critical level i.e. more than 85%. The act of abolishment of Japan National Oil Corporation could be regarded as the model case of the reformation of a public corporation in Japan.The main functions of JNOC include (1) to provide oil exploration activities with risk money, (2) research and development in the field of oil exploration, (3) to manage the national petroleum reserve. And, these important functions will be succeed to a newly established independent administrative entity, which means the Government recognizes the importance of national aid in oil exploration.Of course, there are some problems to be solved in the past JNOC's activities. Since the establishment of JNOC 34 years ago, it has lent and invested about 2 trillion Japanese Yen and has had the accumulated loss of 0.9 trillion Yen. This is mainly why the Japanese oil exploration policy was unsuccessful in strengthening the Japanese oil companies and unexpected changes of international economy such as the rapid appreciation of Japanese Yen occurred.In the 21st century, in order to compete equally with Western Super Oil Majors which have the advantage of capital and technology, it is to some extent essential for the Government to assist the Japanese oil companies. Japan, as the second largest oil consuming country, is responsible for the development of upstream business which gives us a large amount of benefit. In addition, it is necessary for us to establish a core oil exploration company including electric companies, gas companies and sogoshousha together with the Governmental aid, because big projects such as the developments of oil and gas fields amount to 1 trillion yen.

Improved and Standardized Methodology for Oil Spill Fingerprinting

The existing Nordtest methodology for oil spill Identification has over the past 10 years formed an important "platform" for solving oil spill identification cases both in the Scandinavian countries as well as other countries in Europe, the USA and Canada. " Revision of the Nordtest Methodology for Oil Spill Identification " is a cooperative project between the National Oil Spill Identification laboratories in Norway, Sweden, Finland, Denmark and the Battelle Memorial Institute (Duxbury) in the USA. The goals of the project are: (1) to refine the existing Nordtest methodology into a technically more robust and defensible oil spill identification methodology with focus on determination of quantitative diagnostic indices (ratios) and (2) to adjust the revised Nordtest methodology into guidelines for the European Committee for Standardization (CEN). This paper presents the recommended methodology for the analytical oil spill identification part. The sampling techniques and handling of oil samples and background (reference) samples prior to their arrival at the environmental forensic laboratory is not covered in this paper. The recommended methodology approach is a result of documented analytical improvements and a more quantitative treatment of analytical data from gas chromatographic-flame ionization detector (GC/FID) and gas chromatographic-mass spectrometer methods (GC/MS-SIM) and the operational experiences over past few years among the participating forensic laboratories. The experience and literature in the field of oil exploration and production geochemistry have also played an important role for the recommended methodology. The results from a recent Round Robin test carried out among 12 laboratories using this new methodology are presented in a separate paper in this issue (Faksness et at ., 2002d).

Experimental determination of gas migration velocities with non-newtonian fluids

The two-phase flow characteristics of gas in non-Newtonian fluids are important in many applications in various industries. Typical examples include the food processing industry, where it is sometimes desirable to aerate melted chocolate; also the chemical industry, where it is desirable to de-aerate non-drip paint. In the field of oil exploration the drilling mud is non-Newtonian. It is used for cooling the drilling bit, removing the drilled cuttings and maintaining the bottom hole pressure. Typical drilling muds have a yield stress to prevent sedimentation of drilled cuttings; they are also shear thinning to reduce pumping power and circulating pressures. An influx of gas into the wellbore is known as a gas kick and can lead to a blowout. One of the critical parameters in the evolution of a kick is the rate at which the gas influx rises up the well through the non-Netwonian drilling mud. The main parameters governing the gas velocity are the wellbore geometry (typically large annulus), the well inclination (vertical to horizontal), the volumetric flow rates, the volumetric gas fraction (0–100%) and the fluid rheology (yield stress and shear thinning). An experimental programme was set up at Schlumberger Cambridge Research to examine two-phase flows in large pipe and annular geometries using non-Newtonian liquids. The experiments were carried out in a 15 m inclinable flow loop, where air injection was used for the gas phase and aqueous xanthum gum solutions as well as water were used for the liquid. Using an instrumented test section it was possible to measure mean and spatially resolved void fractions together with gas and liquid velocities over a range of two-phase flow conditions. The results for vertical conditions showed that the air-water flows could be characterized as bubbly flows up to a void fraction of 15%, slug flow over 30% and transitional between. For the viscous muds the transition to slug flow occurred below a void fraction of 7.5%. This meant that for most flow conditions the gas would rise through the more viscous mud faster than it would in water. A description of the flow characteristics is developed in terms of the Zuber—Findlay relationship for both pipe and annular flow geometries.