Geological, geophysical and engineering studies carried out by Mitsubishi Petroleum Development Co., Ltd. have led to a discovery of a new oil field situating at the synclinal area between two existing oil fields in the northern offshore Gabon. The 20th century was called “the century of petroleum”. This is attributed to the extremely effective exploration paradigm, namely “anticlinal theory” with aid of reflection seismic survey. This paradigm had been so prevailing that there should be substantial petroleum reserves to be found, if petroleum accumulations are not restricted to anticlines. Recent examples in the world, including projects participated by Mitsubishi, show that there may by considerable amount of petroleum in synclinal areas. It implies that the 21st century would continue to be “the century of petroleum”, if we can establish a new exploration paradigm in lieu of “anticlinal theory”. Sedimentology, sequence stratigraphy, pattern recognition and 3D visualization of seismic data will play important roles in establishing the new exploration paradigm.
Owing mainly to its prolific reserves in Indonesia, INPEX has been enjoying prolific production so far. However, gradually declining reserves (a destiny of the oil and gas E & P business), and the coming contract expiration of major producing block in 2017, have prompted us to cope with these challenges. In order to overcome these challenges, currently we are actively pursuing new opportunities in our core areas (Indonesia and Australia) and the new target areas (the Middle East, the Caspian Sea, Africa and South America). Since the inception in 1966 for the 3 exploration projects in Indonesia, INPEX has experienced five (5) phases of the business growth; (1) Inception, (2) Initial production, (3) Expansion of activities in Indonesia, (4) Expansion of activities outside Indonesia (especially in Australia and ZOCA), and at present, (5) Expansion of activities in the new target areas. During the course of these 5 phases, we have experienced several notable successes, and (equally important for us) several notable failures. Based on these success and failure experiences, we have established the following strategy: (1) Defining the core areas and new target areas, and concentrating on projects in these core and new target areas, (2) Forming a well-balanced portfolio in terms of area (core area/new target area), asset (oil/gas) and projects (exploration/development/producing, non-operator/operator), (3) Pursuing projects with long term potential for post-2017, (4) Searching for high potential opportunities by strengthening relationship with foreign and domestic leading companies, and (5) Increasing effectiveness by keeping slim organization and utilizing outsourcing. We believe there is no special means which leads to success in E & P business. Instead, it is a steady day-to-day effort to try to increase our technical expertise and business experience, which leads to establishing the strategy, continuous challenges to new opportunities, and finally a success in E & P business.
TEIKOKU is currently involved in the petroleum business from upstream through downstream, based on the domestic E & P activities as its starting point, with widespread oil/gas fields in the prefectures of Akitas, Niigata, Chiba and Fukushima (Offshore Iwaki). The objective of its main activities is to attach great importance to producing its own natural gas, from the Green Tuff in Niigata located in volcanic rock formation more than 5, 000m in depth, and to supplying such gas through its own pipeline, the most extensive pipeline network in Japan. With such background and objective, TEIKOKU in conscious about shifting “From Oil to Natural Gas” and “From Upstream to Middle & Down Stream (piline business)” in Japan, as the main business of the company. On the other hand, the compbny intends to expand its international business with technical and managerial know-how accumulated in the E & P activities, including the experjences of domestic transactions of natural gas, and in order to meet such a purpose, we reviewed and restructured our international business strategy to establish our mid-to long-term core areas. Here I would like to introduce the current status of TEIKOKU's E & P business in Japan, the technical concerns of the domestic natural gas business, as well as the upcoming perspectives in the international business scene.
The oil and gas industry in Japan began in the middle of 19th Century, in the Niigata and Akita basins, therefore, hydrocarbon exploration has been conducted for over a hundred years, with more than 1000 wells drilled in the two basins. The fact that there has been no significant discovery for two decades is an indication that exploration for hydrocarbons in both basins has reached a mature stage. As a result, JAPEX has been shifting its activity from these areas to other areas such as Hokkaido and overseas. However, we still see the potential for resources growth in both Niigata and Akita basin, and continue our efforts to confirm reserves in existing fields and surrounding areas. In carrying out Japex's domestic activities, we attempt the following: (1) cut the exploration costs (2) apply new exploration tools (3) farm out concession areas to reduce risk, increase the opportunities and reduce spending. In our overseas activities, following guidelines are observed (1) focus on selected areas (2) concentrate on play types in which Japex has expertise (3) balance exploration activity with asset acquisition. At any rate, a successful wildcat is the ultimate way to prove that oil and gas exploration is still a profitable business.
As a result of the merger of Nippon Oil Co., Ltd. and Mitsubishi Oil Corporation in April, 1999, the asset portfolio of Nippon Oil Exploration Limited (NOEX) has not only expanded in size but also become fairly well-balanced even though the two companies were different in way of developing the upstream business. Activities of the projects of NOEX are presented in this paper focusing on operating projects. Also presented is an outline of the strategies of NOEX, as a subsidiary of a leading marketing and refining company in Japan, Nippon Mitsubishi Oil Corporation, aiming at further expansion and improvement of profitability.
Current activities of Itochu Oil Exploration Company Ltd. in Indonesia, Azerbaijan, UK North Sea, Algeria and others are reviewed. Technical issues of each project are introduced and current efforts to challenge against those are explained. Core areas and types of new projects being sought by the company are introduced and discussed. Because the company profit of upstream business will be heavily affected by the uncertainties in reserves revision of projects, world oil price and currency exchange rate, technical challenge and project portfolio are to be well designed to minimize risks in uncertain future development of various factors.
Experimental studies were carried out for investigating the applicability of the CO2-Water Alternating Gelant Injection Process (CAG) which was proposed by the author to improve oil recovery. First flood experiments were conducted with linear glass-bead-packed cores. The oil-saturated cores were firstly flooded by water, and later flooded by alternating slug injection of CO2 water and gelant (CAG). The oil recovery increased after waterflood by 12.1% for the high permeability core and by 24.2% for the low permeability one. The increase in in-situ fluid viscosity with gelation during CAG has improved oil displacement efficiency through mobility-control effect and led to these incremental oil recoveries. Second flood experiments were conducted with two linear glass-bead-packed cores of different permeabilities mounted in parallel. The oil-saturated cores were simultaneously flooded by 3.0PV of water, 1.4PV of CAG and 1.6PV of water in sequence. Experimental results showed that 29.1% of incremental oil recovery was obtained by CAG and succeeding waterflood, and its effect of improving oil recovery was much larger than polymer flood. The increase in oil recovery by CAG was caused by following mechanisms: (1) The increase in in-situ fluid viscosity with gelation improved oil displacement efficiency in the high permeability core. (2) Water effectively swept the oil in the low permeability core after the gel plugged the high permeability core. Especially the second effect of improving sweep efficiency by permeability profile modificationwas found to be large.
The susceptibility of pitting and cracking of super 13Cr steels in light sour environment was systematicaly investigated by a notched bent beam test using autoclave. In mild condition such as chloride free solution at 25°C, the steels presents the passive state with no pitting and no cracking. With increase in chloride concentration, corrosion morphology changes from passive state into either pitting or general corrosion allowing hydrogen entry into steel so that SSC can occur. In higher temperature condition, passive film also becomes unstable to cause either pitting or general corrosion, however, cracking susceptibility decreases. These events suggest that a principal mechanism of SSC of super 13Cr steel is hydrogen embrittlement in condition that some breakdown of passive film undergoes. The major environmental factors affecting the pitting and cracking susceptibility are H2S partial pressure, temperature and chloride concentratoin, while pH effect is relatively small. The pitting and cracking resistance depends on alloy composition especially Mo content, but hardly influenced by strength of material.
Reservoir geochemistry is a recently developed sub-field of petroleum geochemistry and focuses on Chemical properties of formation fluids (petroleum and water). Fluids in reservoirs are often compositionally heterogeneous. These heterogeneities are inherited during field filling. On the other hand, oils within a continuous reservoir have similar compositions. These observations offer us the basis of reservoir geochemistry. Reservoir eochemistry has a lot of important and practical applications such as reconstruction of petroleum migration pathway and reservoir filling history, evaluation of reservoir continuity, and allocation of commingled production.