200億年前に宇宙が誕生、約40億年前に地球が生れたといわれるロマンあふれる自然界、大宇宙がもたらす物質の生成核エネルギーから生命の誕生に至り人類発祥が明らかとなった。これらは物質の変革は核分裂・核融合の巨大エネルギーが原点であることから、人類が利用可能とする核エネルギーの基本法則は大宇宙がなす自然循環に従った利用法則が必要不可欠となる。すなわち、地球号も自然界の原子炉構造であることから、人工的な核エネルギー利用は、地殻循環再生の地球構造の運動に従って、核廃棄物の自然循環処理が必要不可欠である。

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The late Cretaceous, Paleocene, late Middle to Late Eocene, Oligocene and early Early Miocene larger（benthonic）and planktonic foraminifera were confirmed for the first time, in addition to Early-Middle Miocene larger foraminifera, from the Sashida Limestone included basalt pebbles beside the outcrop, which was covered by river-construction, and near there, Sashida, Kamo-Gun, south Izu Peninsula, Japan. The Sashida Limestone consists of clastic carbonate rocks of various ages from the late Cretaceous through early Early Miocene to late Miocene or early Pliocene. From the research conclusion, the geology and geohistory of the Cretaceous-Paleogene Shimanto Group and Paleogene Setogawa Group along the Pacific Ocean as the pre-Yugashima Group, and the locus of lateral mobility of the Izu landmass of the antecedent of the Izu Peninsula were indicated as further research.

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Serpentine seamount was reviewed with recent seven Shinkai 6, 500 dives at Izu-Bonin and Mariana forearcs. The seamounts consist mostly of serpentine flows with huge xenoliths of peridotite, high-pressure type metamorphic rocks such as jadeite-quartz assemblage and aragonite, glaucophane schist as well as MORB like basaltic rocks and chert. Active seamount has the following three characteristic features ; 1) serpentine flow, 2) carbonate chimney, and 3) huge peridotite xenolith in the flow. Serpentine flow shows a lobate structure with several meters width and 2-3 m high, sometimes flows down along the steep cliff. Drilling results indicate that flow unit shows the sedimentary structure similar to the interior structure of the mud diapir. Carbonate chimneys exist as an isolated tree and more than 20 chimneys stand make a line in some cases. Active carbonate chimney has yellowish green bacterial mats on the surface but dead ones are covered with thin black manganese coating. The fate of carbonate chimneys is fell down and dissolves into the sea water when the depth exceeds more than 4, 000 m, becomes a member of sediments when buried and sometimes makes a vein.
In the metamorphic belts onland such as Sanbagawa, Kamuikotan metamorphic terrains and Mineoka belt there are serpentinite bodies of both alpine and stratiform types. The former type was thought to be of solid intrusion along fault. These serpentinite bodies yield white sediments as a vein, layer of sediments as well as rodingites. Rodingites always crop out with serpentinites in the Alps and other orogenic belts. Serpentinite bodies have highly sheared and brecciated parts and most geologists thought those parts to be the results of strong shearing when solid intrusion. However, if we look at the body carefully, sedimentary structure and white veins, and sediments will be frequently observed and the body is closely accompanied by rodingites.
We strongly insist to think that these white materials are the products of the carbonate chimneys and sedimentary structures are also the product of serpentine flow at the forearc serpentine seamount and emplace into the metamorphic terrains during the secondary processes. During the emplacement, rodingite and magnesite ore would be formed by metasomatism with serpentinites.
Most of the serpentinites in the orogenic belt must be of serpentine seamount origin such as in Izu-Bonin, Mariana, Tonga and Middle America Trenches where the crust are thin compared with those of the ordinary island arcs and continental margins.

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大陸棚画定調査は政府一体として取り組まれた事業である。その目的は国連海洋法条約に定められた「大陸棚」について、科学的根拠を含む延伸大陸棚の限界に関する情報の取りまとめを行い、国連へ提出することにあった。産総研の海洋地質に関わる研究者は、海域調査の実施、採取岩石試料の分析・解析・解釈、ならびに国連への申請書案作成のための作業部会への参加を通じて、海洋地質学の専門家集団としての総合力を発揮することにより大陸棚画定調査に貢献した。関係省庁各機関が協力してとりまとめられた日本の延伸大陸棚に関する情報は、2008年11月12日、日本政府が国連の「大陸棚の限界に関する委員会」に申請書として提出した。そして、同委員会より、申請の審査の結果としての「勧告」を2012年4月26日に日本政府は受領した。本報告では、「大陸棚」および日本の「大陸棚」に関する簡単な解説とともに、科学的な情報が基礎となってわが国の海域における権益の及ぶ範囲の増大に貢献できるという稀有な機会に、産総研の研究者が組織の一員として、また研究者として参加したことの経緯とその成果を示し、さらに、このような事業を実施するうえでの問題点について議論した。

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 This paper reviews the geology, petrology, and tectonics of the Proto-Izu-Mariana arc against the Honshu arc, Japan, since 15 Ma, to formulate current topics related to the Pacific-type orogeny.
 Since the first pioneering work by Sugimura (1972), which placed the plate boundary on-land Japan north of the Izu peninsula collision-accretion tectonics of the Proto-Izu-Mariana arc against the Honshu arc started to be extensively investigated through multi-disciplinary methods. Aoike (1999) proposed a comprehensive scenario of five successive accretions of Proto-Izu to the present, with all bounded by top- and bottom-faults since 15 Ma. Oroclinal bending of the Honshu arc began simultaneously with the collision and indentation of the Proto-Izu arc, as is well documented by the Neogene paleomagnetic declination of sedimentary rocks in the Kanto district (Niitsuma et al., see summary, 1989). The entire Izu-Mariana arc is subducting without any accretion now under Honshu, as is well documented by seismic tomography imaging by Hasegawa et al. (see Hasegawa et al., 2010).
 Tanzawa Tonalite–Trondhjemite–Granodiolite (TTG) pluton intruded into the already-accreted Tanzawa Group at 4 Ma (Tani et al., 2010), resulting in a contact metamorphic aureole ranging from amphibolite through greenschist to zeolite facies at a depth of ca. 10 km, and tectonically denudated along the Kan-nawa fault to be exposed on the surface by 1.0 Ma.
 The Proto-Izu-Mariana arc was built on the Pre-Paleogene, presumably Cretaceous MORB crust on which boninitic and fractionated silicic lava flows accumulated since 48 Ma, which is older than the bending of the Hawaii–Emperor seamount chain at 43 Ma. Hence, we need another plate off Proto-Ogasawara arc, called North New Guinea plate (Seno, 1985), and ridge subduction underneath Ogasawara arc to initiate subduction magmatism.
 Both calk-alkali rock series (CA) and coeval blueschist–eclogite rocks are exposed along the inner wall of the Izu–Mariana trench. This strongly suggests that extensive tectonic erosion occurred, resulting in the coexistence of two rock units that were formed 100-150 km from each other horizontally, i.e., rocks on the volcanic front and rocks on the descending oceanic slab.
 Petrogenesis of juvenile crust and TTG rocks are being debate with two models: basaltic arc magma fractionation (Kawate and Arima, 1998) and delaminated mafic lower crust (Nakajima and Arima, 1998). In the latter model, a difficulty is derived from density at the Moho depth and small size of delaminated residue. Instead, extensive tectonic erosion that transports not only the upper crust but also the lower mafic crust together with parts of the descending slab could be more plausible than these two models in order to present a thinner mafic lower crust.

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