著者
上田 広和 三瓶 良和 日浦 祐樹 石橋 正敏
出版者
石油技術協会
雑誌
石油技術協会誌 (ISSN:03709868)
巻号頁・発行日
vol.72, no.4, pp.333-346, 2007
被引用文献数
3

Oil fields occur in the Sagara district of Shizuoka Prefecture, despite the disadvantageous geological conditions of a fore-arc setting. We investigated the petroleum system of this fore-arc basin in southern Shizuoka Prefecture based on hydrocarbon compositions of oils, source rock potential, organic matter type, and burial history of the Paleogene to Neogene sediments. Argillaceous rock samples from the MITI-Omaezakioki well and from outcrops in the Kakegawa and Sagara districts were analyzed for geochemical properties by CHNS elemental analyzer, Rock-Eval pyrolysis, and GC/MS.<br>Various maturity parameters in the Sagara oils indicate differing maturity levels, ranging up to the condensate zone. The range in maturity parameters is wider in the northwest flank of the Megami anticlinorium than in the southwest flank. The upper layers of the Lower Miocene Towata Formation and the lower layers of the Lower Miocene Matsuba Formation have relatively high potential for hydrocarbon generation (up to TOC=0.9 wt%, S<sub>2</sub>=2.8mg/g and HI=350mg/gC). The highest-potential layer of the Matsuba Formation was probably deposited in a highly productive marine environment during deposition of siliceous clastic sediments. No equivalent high-potential layers were identified in the MITI-Omaezakioki well, suggesting that the organic-rich layer formed only in the northern part of the basin. In the Eocene-Oligocene Mikura Group, layers relatively rich in TOC (up to 0.7 wt% in over-matured black shale) were observed in the Kakegawa area and also in the MITI-Omaezakioki well. According to epimerization of sterane and hopane isomers, thermal gradient was higher in the northern part of the basin than in the south. In both areas the Kurami Group only reached medium-light oil zone, whereas the Mikura Group reached the condensate zone. The thermal structure of the basin thus changed significantly between the Paleogene and Neogene.<br>On the basis of basin modeling simulation of the MITI-Sagara well, medium-light oils (Ro=0.7-1.0%) were generated in the Mikura Group at ca. 29 Ma and 15 Ma, and condensates (Ro=1.2%) at ca. 2 Ma. The Kurami Group generated medium-light oils (Ro=0.7-1.0%) at ca. 15 Ma and 2 Ma. Therefore, the ca. 2 Ma condensates from the Mikura Group migrated and were contaminated by oils from the Kurami Group and bitumens from the upper reservoir layers (e.g. Sagara Group).
著者
手塚 和彦 玉川 哲也
出版者
石油技術協会
雑誌
石油技術協会誌 (ISSN:03709868)
巻号頁・発行日
vol.78, no.1, pp.36-46, 2013 (Released:2015-04-03)
参考文献数
24
被引用文献数
1

It is well known that horizontal drilling and hydraulic fracturing are key technologies to carry the shale gas revolution forward to success. Efforts in enlarging reservoir contact are needed to realize commercial production from shale reservoir whose permeability is supposed to be in the order of nano-Dary to micro-Darcy. To design mud system, to keep wellbore stability and/or to optimize hydraulic fracturing fluid and pumping schedule, knowledge about rock mechanics and stress environment is quite important. A technical area of analyzing, integrating and interpreting such knowledge is called “geomechanics”.In this paper, we describe geomechanics from various aspects by focusing application to hydraulic fracturing technology. We review mechanical property of shale and some important parameters such as Young's modulus, Poisson's ratio, UCS, hardness and brittleness. Then, we show how those parameters impact hydraulic fracturing. A geomecanical models which consist of mechanical faces, mechanical properties and stress information is briefly explained. A case study of microseismic monitoring in Barnet shale field is introduced to reveal created hydraulic fracture patterns and those relationship to production that are significantly affected by pre-existing natural fracture system.
著者
大賀 光太郎
出版者
石油技術協会
雑誌
石油技術協会誌 (ISSN:03709868)
巻号頁・発行日
vol.79, no.6, pp.419-423, 2014 (Released:2016-07-15)
参考文献数
10

Coal reserve of Japan is about 20 billion tons. A half of them is in Kyushu and the other is in Hokkaido. The most gassy coal field in Japan is Ishikari coal field in Hokkaido. In Ishikari coal field there were so many underground coal mines, but now all of them were closed. The gas content of coal in the Ishikari coal field is more than 12 m3/t and CBM resources in Ishikari coal field is estimated about 40 billion m3.There are some reasons why CBM has never been developed in the coal field. One is that the Ishikari coal field is mountain area and most of it is covered with National Forest. Therefore, it is difficult to find the drilling site from the surface and to develop CBM on a large scale. The other one is that it is difficult to drill wells in a soft coal seam such as Yuubari coal and to maintain the wells. Therefore, we are planning to develop CBM to use for local energy in this area.
著者
土田 定次郎
出版者
石油技術協会
雑誌
石油技術協会誌
巻号頁・発行日
vol.26, no.1, pp.20-28, 1961
被引用文献数
1

The middle part of Ishikari Plane (or Sapporo Lowland) is situated in Lat. 40&deg;00'-43&deg;25' N. and Long. 141&deg;12'-141&deg;53' E. In this plane, there are the Neogene Tertiary formations which are overlaid with the Quaternary formations of about 100m in thick.<br> 1. The Neogene Tertiary formations cropping out in the surrounding mountains district are overlaid with unconformity on the Paleogene coal-bearing formations, the Cretaceous System, and so-called &ldquo;Pale-ozoic&rdquo; formations.<br> 2. In the Neogene formations of this plane, according to the stage of depositon, there are marked variations in the density of deposits and distribution of fossils. There is no remarkable unconformity, however, in the Neogene Tertiary formations and each formation distributes in all the area, but the thickness of formations is changeable and most thick between the Nopporo Hill and Umaoi Hill.<br> 3. On the land surface or near the surface of this plane, igneous rocks have not been discovered and will not be discovered in future.<br> 4. The Neogene formations have folded structures with axes of approximately north-south direction and they are thought to have been resulted from upheavals of the Hokkaido Backbone Mountain Lands or Hidaka Mts.<br> 5. While the synclinal parts of folding structures are large and broad, their anticlinal parts make steep dip wings and narrow forms. Anticlinal parts are assymmetrical forms and thir axial planes are inclined to west ; that is, they show the nature of &ldquo;west steep-east slow.&rdquo;<br> 6. The axial planes of anticlinal structures in the eastern area are extreamly dipping. The angle of dip is smaller in the western area and it takes almost the similar shape of symmetrical anticline structure in the Ishikari coastal region. On the contrary, in the northern mountainous districts of the plane, the axial planes are inclined to east and the anticlinal structures show &ldquo;east steep-west slow&rdquo; character. In these mountain regions where crops out of basement complex as Kobato Paleozoic sediments, folding waves are pushed back for eastern side against the lateral forces caused by the upheaval of backbone mountains. Consequently, these folding waves advanced towards the Neogene basin axis <sup>(10)</sup> (Tomakomai-Takikawa Line) from both sides of east and west mountains (Fig. 12).<br> 7. In the plane, each anticline structure is continuous without faults or echelon arrangement, and there are some upheavals making dome-like structures. On the contaary, however, there are some sinking areas making structural depressions along the synclinal axes. These depressons are distributed at regular intervals, and the distribution of the recent rivers are related to these depressions.<br> 8. The meander zones of rivers distribute centering around Masarikappu near Ishikari Coast elliptically and radially. This distribution shows that the southern mountains slow upheave contrary to the northern mountains (Kobato Mts.).<br> 9. Accordingly, it is revealed that each basement complex (pre-Neogene) of mountains in the northern, southern, and eastern parts of the plane belongs to different geologic structural unit. It is thought that these three blocks made different block movements and these geological movements produced effects on the Neogene Tertiary structure in this plane.<br> The above are interpreted as follow.<br> (1) Southern mountains to which the Ezo-Fuji Volcanics belong are a range from the Central Mountains in North-East Japan where is the Nasu Volcanic Zone.<br> (2) The eastern mountain range is not connected with the land of North-East Japan.<br> (3) The Abukuma and Kitagami ranges in North-East Japan belong to tne same mountain series with Kobato range in the north of Sapporo Lowland.<br> (4) There are geological structure lines between Sapporo Lowland and mountainous districts.
著者
高橋 靖弘
出版者
石油技術協会
雑誌
石油技術協会誌 (ISSN:03709868)
巻号頁・発行日
vol.81, no.4, pp.281-288, 2016 (Released:2018-05-09)

This paper presents Akita Prefecture's “Second Phase Strategy of New energy-related industries in Akita within its industry strategies.Akita, blessed with energy resources such as wind, geothermal, and biomass, is one of Japan's leading regions in the potential of creating renewable energy.While promoting the expansion of renewable energy, Akita has worked together with cooperating industries to formulate a strategy that tackles and greatly increases job creation as well as industrial development, and for that purpose has had the expansion and development of various policies to approach the issue.
著者
重川 守
出版者
石油技術協会
雑誌
石油技術協会誌 (ISSN:03709868)
巻号頁・発行日
vol.50, no.1, pp.9-16, 1985 (Released:2008-03-27)
参考文献数
14
被引用文献数
2 9

Stable carbon isotope ratio of 13C to 12C is applied to problems of geochemical correlation of crude oil to source rock on the assumption that isotope ratio of kerogen is heavier by ranging from 0.5 to 3‰ in δ13C values than that of oil when oils and kerogens are genetically related. The accumulated oils have δ13C values ranging from -23 to -22‰ and, consequently, those of source kerogens are expected to be in range from -23 to -19‰ in the Niigata basin. The source kerogens appear at two stratigraphic horizons. One of them is the Nanatani Formation to the lower part of the Teradomari Formation (source “D”) and the other is the top of the Shiiya Formation to the base of the Nishiyama Formation (source “S”). The source “S”, which is confirmed for the first time using stable carbon isotopes, is distributed in the area of the Niitsu, Minami Aga and Aga Oki oil fields, but it is absent in the area of Higashi Niigata and Matsuzaki gas fields. From this result, it may be inferred that the source “S” contribute to generation of the oils accumulated in the Shiiya and the Nishiyama Formations in these oil fields.
著者
江川 堯
出版者
石油技術協会
雑誌
石油技術協会誌 (ISSN:03709868)
巻号頁・発行日
vol.62, no.2, pp.112-121, 1997 (Released:2008-03-27)
参考文献数
4

Construction of a natural gas pipeline from Niigata to Sendai was completed in March 1996. Pipeline construction consists of engineering works such as civil engineering, material technology, welding technology and so on. This lecture presents the following items regarding the engineering works to be overcome and some technical skills associated with the project are introduced.i) Seismic designii) Material technology, welding technology, field bendingiii) Bridge design, tunnel designiv) Leak detection
著者
村本 宏司 大澤 正博 木田 昌宏 有坂 春彦
出版者
石油技術協会
雑誌
石油技術協会誌 (ISSN:03709868)
巻号頁・発行日
vol.72, no.1, pp.76-88, 2007 (Released:2008-10-30)
参考文献数
25
被引用文献数
3 14

METI “Sado Nanseioki” wells were drilled in the deep water southwest offshore of the Sado Island in the Japan Sea to explore the Awabi Structure after the MITI “Sadooki Nansei” seismic survey.Along with the presence of Direct Hydrocarbon Indicators around the crest of the structure, methane hydrate and oil seepage were recovered during the site survey prior to the drilling, which indicate an existence of the active petroleum system.METI “Sado Nanseioki” wells proved a distribution of the thick Neogene sediments in the deep water and discovered a 15 meter-thick oil column in the lower part of the Shiiya Formation. Detailed paleontological, geochemical and fluid inclusion analyses were carried out, and resulted in a reliable correlation to the Niigata standard stratigraphy and understanding of hydrocarbon history of the structure.A severe truncation surface revealed by the seismic survey was identified within the upper part of the Lower Teradomari Formation at about 8.5 Ma. Structural configuration of the Awabi Structure varies greatly between above and below the truncation surface. Above it, the structure is an asymmetrical anticlinal structure accompanied by a reverse fault on the western flank. Below it, the structure is an N-S trending nose structure. Structural growth commenced in the southern part during the time of the Shiiya Formation, and culminated after 1.3 Ma with growth center shifting north- and northeast-ward.A close genetic relationship was proved between oil, hydrocarbon shows, methane hydrate and oil seepage at sea bottom. Hydrocarbon generation in the Lower Teradomari or Nanatani Formation, temporal trap in the Lower Teradomari Formation, migration into the Shiiya Formation and leakage to the sea bottom through many small normal faults at the crest was clearly interpreted.The MITI seismic survey and the METI wells provided important insight about the petroleum system of the deep-water part of the Japan Sea.
著者
今田 美郎 川井 健史 平山 鋭 富田 伸彦
出版者
The Japanese Association for Petroleum Technology
雑誌
石油技術協会誌 (ISSN:03709868)
巻号頁・発行日
vol.71, no.6, pp.556-563, 2006
被引用文献数
1

A reservoir modeling using simulation software on the market is popular to evaluate production profile and has specific requirement in an each phase through a project. Generally, a simpler model is preferred to examine many cases about production scenarios for a commercial evaluation in feasibility study phase. So, it is very important how to express subsurface uncertainty in a simple reservoir model.<br>A condensate banking phenomenon which reduces productivity near the wellbore is a typical feature of gas reservoir, especially condensate rich gas reservoir. Evaluation of the condensate banking is an important issue from a viewpoint of production profile evaluation because of requirement from market to maintain plateau of production for the project. One of popular techniques to express the condensate baking is local grid refinement (LGR) method applied around each well in the compositional simulator.<br>However, LGR application may not be a preferable option in the feasibility study phase, because more complicated reservoir model requires more calculation time. So, PI multiplier method was introduced without LGR option to keep simplicity of the reservoir model.<br>An investigation of the PI multiplier applied in the coarse grided full field model without LGR to take into account productivity reduction by condensate baking has been presented in this paper.
著者
安藤 慎吾
出版者
石油技術協会
雑誌
石油技術協会誌 (ISSN:03709868)
巻号頁・発行日
vol.79, no.6, pp.434-440, 2014

Soon after US shale gas revolution, Canadian shale gas development is also energized, especially in Western Canada. Canada has the advantage of availability of industrial equipment, materials and pipeline connecting to US due to the neighboring. On the other hand, rapid development may raise concerns over the issue of water management in the respect of usage and disposal. In British Columbia, Oil and Gas Commission is positively supervising and managing water usage with consideration for environmental impacts. And operating companies in Canada are also trying and developing new technologies and methods of production which can reduce usage of fresh water. In the shale gas project in Canada which INPEX is joining to, the operator is working on water management in advance of future fullscale development based on assessment of environmental impact, and has newly developed and tested fracturing pumping system which could provide a capability of utilizing raw water of non-potable deeper aquifer.
著者
松澤 明
出版者
石油技術協会
雑誌
石油技術協会誌 (ISSN:03709868)
巻号頁・発行日
vol.51, no.4, pp.298-313, 1986 (Released:2008-03-27)
参考文献数
1
著者
伊藤 谷生
出版者
石油技術協会
雑誌
石油技術協会誌 (ISSN:03709868)
巻号頁・発行日
vol.65, no.1, pp.103-109, 2000 (Released:2008-03-27)
参考文献数
31
被引用文献数
18 32

The collision of the Kuril arc against the Northeast Japan arc has made a conspicuous crustal structure from the Hidaka mountain range to the Ishikari-Tomakomai lowland, Hokkaido, Japan, since Miocene. Recent advance of deep seismic reflection studies has revealed that the Kuril arc lithosphere is delaminated at about 23km deep in the lower crust in the Hidaka collision zone. The upper half of the lithosphere (upper crust+upper portion of the lower crust) is thrust westward on the Northeast Japan arc, whereas the lower half (lower portion of the lower crust+upper mantle) descends down. The wedge of the Northeast Japan arc lithosphere intrudes eastward into the delaminated Kuril arc lithosphere. The structure is called as a “delamination-wedge structure”. In the western foreland area of the Hidaka mountain range, the west-verging fold-and-thrust belt occurs more than 70km wide involving the pre-Tertiary strata. The activity of the belt has shifted westward since the initiation of the collision. The shortening length in the foreland fold-and-thrust belt is about 60km, which is nearly equal to the delamination-wedge length toward the colliding direction. The two lines of evidence mentioned above, the westward shift of the activity and the coincidence of both lengths, indicate that the fold-and-thrust belt has been growing associated directly with the formation of the delamination-wedge structure.