Petrology of tremolite rocks in the high-pressure metamorphic terranes

高压变质地体透闪石岩石学

• 批准号: 14540452
• 负责人: MAEKAWA Hirokazu
• 金额: $ 2.05万
• 依托单位: Osaka Prefecture University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2002
• 资助国家: 日本
• 起止时间: 2002 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-14540452/
• 关键词: serpentinite; perigdotite; high-pressure belt; tremolite; metasomatism; Mariana; serpentinite zeamount; 蛇紋岩海山; 高圧変成帯

The Franciscan Complex, California, and the Kamuikotan metamorphic belt, Japan, are accompanied by serpentinite melange with deeper high-grade metamorphic rocks, whereas the Sanbagawa metamorphic belt, Japan, contains less amounts of serpentinite and is not accompanied by any serpentinite melange. The former were probably formed under a tensional stress regime, and the latter under a compressional one. The restricted occurrence of serpentinite to the high-grade pelitic schist in the Sanbagawa belt suggests that the serpentinites had been supplied from wedge mantle into pelagic sediments on the top of subducting plate at the initiation of accretion. Tremolite rocks and phengite-chlorite schists near serpentinite in the Sanbagawa belt and from Chamorro Seamount, Mariana forearc, may suggest the widespread metasomatism along the boundary between wedge mantle serpentinite and pelagic sediments. Further research on the mechanical and physico-chemical behaviors of these metasomatic rocks are important to understand the phenomena along the subduction boundary between oceanic and land-ward plates.

加州的方济各杂岩和日本的Kamuikotan变质带都伴随着蛇纹岩混杂岩和更深的高级变质岩，而日本的Sanbagawa变质带则含有较少的蛇纹岩，并且不伴随任何蛇纹岩混杂岩。前者可能是在张性应力状态下形成的，而后者可能是在挤压应力状态下形成的。三坝川带中蛇纹岩仅产于高级泥质片岩中，表明蛇纹岩是在俯冲板块顶部的大洋沉积物中，在增生作用开始时由楔状地幔提供的。三巴川带和马里亚纳前弧查莫罗海底山蛇纹岩附近的透闪石岩和多硅白云母-绿泥石片岩可能表明，沿着楔状地幔蛇纹岩和大洋沉积物之间的边界，沿着存在广泛的交代作用。深入研究这些交代岩的力学和物理化学行为，对于理解大洋板块和向陆板块之间的俯冲边界沿着现象具有重要意义。

项目成果

前川寛和: "プレート沈み込み帯における蛇紋岩化作用"月刊地球号外. No.43. 67-74 (2003)

Hirokazu Maekawa：“板块俯冲带中的蛇纹石化”，地球月刊特刊，第 43 期（2003 年）。

Maekawa, H.: "Serpentinization in the subduction zone"Chikyu Monthly. 43. 67-74 (2003)

Maekawa, H.：“俯冲带的蛇纹石化”地球月刊。

笠原順三他20名: "地震発生と水 担当箇所3.3蛇紋岩ダイアピルp.140-151."東京大学出版会. 392 (2003)

Junzo Kasahara 等 20 人：“地震发生与水：第 3.3 节蛇纹石底辟，第 140-151 页。”东京大学出版社 392。

笠原順三他20名: "『地震発生と水』 担当箇所 3.3 蛇紋岩ダイアピル p.140-151"東京大学出版会. 392 (2003)

Junzo Kasahara 等 20 人：“‘地震发生和水’第 3.3 部分蛇纹岩底辟 p.140-151”东京大学出版社 392 (2003)。

Maekawa, H., Yamamoto, K., Ueno, T., Osada, Y., Nogami, N.: "Significance of serpentinites and related rocks in the high-pressure metamorphic terranes, circum-Pacific regions"International Geology Review. (in press).

Maekawa, H.、Yamamoto, K.、Ueno, T.、Osada, Y.、Nogami, N.：“环太平洋地区高压变质岩中蛇纹岩及相关岩石的意义”国际地质评论。