書誌事項
- タイトル別名
-
- Structural and petrological characteristics of ultramafic rocks in Hayachine-Miyamori Ophiolite
この論文をさがす
抄録
Hayachine-Miyamori ophiolite is an Ordovician arc ophiolite located in the northwestern margin of the South Kitakami Massif. The ophiolite has been divided into an aluminous spinel ultramafic suite (ASUS) and a chromite-bearing ultramafic suite (CRUS) depending on petrographic and mineral chemical features. The Hayachine complex is mostly composed of ASUS. The Miyamori complex is mostly composed of CRUS peridotites and pyroxenites with 1–2 km-size patchy domains of ASUS. In this study, structural analysis of the Hayachine-Miyamori ophiolite was carried out in order to examine the origin of peridotite. The peridotite samples were taken from the Hayachine ASUS and Miyamori ASUS. These peridotites are harzburgites-lherzolites and show coarse grained textures (1–3 mm), undulatory extinction, irregular grain boundaries and exsolution lamellae in pyroxene crystals. There is no distinct difference in the chemical compositions and olivine crystal-fabrics between the Hayachine ASUS and the Miyamori ASUS peridotites, though they are geochemically distinct. Spinel compositions have relatively low Cr# (0.13–0.31) and lower Ti contents (0.02–0.05). The olivine crystal-fabrics were quantified using VP-Flinn Diagram and show A-type and AG-type patterns (Fabric Index Angle: 7°–53°, VP anisotropy: 5.7–8.9%). J-index values show relatively weak concentrations less than 3.5, possibly due to dynamic recrystallization. It shows that the studied ASUS peridotites preserve textures and crystal-fabrics deformed under higher temperature such as solidus condition in the uppermost mantle.
収録刊行物
-
- 静岡大学地球科学研究報告
-
静岡大学地球科学研究報告 44 (0), 31-46, 2017-07-31
国立大学法人 静岡大学理学部地球科学教室
- Tweet
キーワード
詳細情報 詳細情報について
-
- CRID
- 1390008620055675520
-
- NII論文ID
- 130008118580
-
- NII書誌ID
- AN00103190
-
- HANDLE
- 10297/10366
-
- ISSN
- 03886298
-
- 本文言語コード
- ja
-
- データソース種別
-
- JaLC
- IRDB
- CiNii Articles
- KAKEN
-
- 抄録ライセンスフラグ
- 使用不可