Comparative study on structural geology of tectonic melange,olistostrome and mud volcano.

构造混杂岩、橄榄石和泥火山构造地质对比研究.

• 批准号: 03804064
• 负责人: SAKAI Harutaka
• 金额: $ 1.02万
• 依托单位: KYUSHU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1991
• 资助国家: 日本
• 起止时间: 1991 至 1992
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-03804064/
• 关键词: Melange; Olistostrome; Submarine Slide; Subaqueous Pyroclastic Flow; Mud Volcano; Lesser Himalayas; Nappe; Augen Gneiss; 水中大砕流; オリストストロ-ム; レッサ-ヒマラヤ

As a result of present study,I obtained the following new knowledge and idea about olistostrome and melange. 1.Olistostrome(huge submarine slide) A huge submarine slide intercalated in the Taishu Group in Tsushima has a characteristic change of geologic structures from the base to the top.(1)injection of sand dyke and sheet below the base,(2)low-angle normal faults above the base,(3)gentle and closed folds,(4)recumbent folds and low-angle thrusts, (5)box-shaped and rootless folds,(6)chaotic slump-ball zone. This change of structures can be a criteria to distinguish olistostrome from tectonic melange. 2. Tectonic Melange Augen gneiss exposed along the Main Central Thrust(MCT) zone in the Himalayas is a kind of tectonic melange which has under-gone deformation along plate boundary in the middle to deep part of crust. It cane be originated by slow cooling and shearing of inner part of sheet-formed leucogranite.Tectonic melange on the sole of para-autochthonous klippe and nappe in the Lesser Himalayas has a characteristic rotation texture of cataclastic grains. Garnets in the gneiss along the MCT have also rotation texture,so called snow-ball texture. It is highly possible that rotation texture is a characteristic feature in the shear zone along low-angle thrust and become a criteria to distinguih tectonic melange from olistostrome.

通过目前的研究，我获得了以下关于olistostrome和melange的新知识和新想法。1.巨型海底滑梯（巨型海底滑梯）位于对马岛太树群中的巨型海底滑梯，其底部到顶部的地质构造变化具有特征性。(1)基底下方砂堤和砂片的注入，(2)基底上方低角度正断层，(3)平缓封闭褶皱，(4)平卧褶皱和低角度逆冲，(5)箱形无根褶皱，(6)混沌滑塌球带。这种构造的变化可以作为区分板块与构造混杂岩的标准。2. 构造混杂岩沿喜马拉雅中央逆冲带暴露的奥根片麻岩是地壳中深部沿板块边界发生变形的一种构造混杂岩。它可能是由于片状浅色花岗岩内部缓慢冷却和剪切而形成的。小喜玛拉雅山副原生推覆带底部的构造混杂岩具有碎裂颗粒的旋转结构特征。沿MCT的片麻岩中的石榴石也具有旋转纹理，称为雪球纹理。旋转结构极有可能是低角逆冲剪切带的一个特征，并成为区分构造混杂岩与橄榄断层的标志。

项目成果

酒井治孝: "ヒマラヤ山脈と南部フォッサマグナ-ふたつの衝突帯を比較する" 科学. 62. 445-450 (1992)

Harutaka Sakai：“喜马拉雅山和南大窝 - 两个碰撞带的比较”《科学》62. 445-450 (1992)。

H.Sakai: "Tectonics and sedimentation of the Tertiary sedimentary basins in the northern Kyushu." Mem.Geol.Soc.Japan. No.42. (1993)

H.Sakai：“九州北部第三纪沉积盆地的构造和沉积”。

酒井 治孝: "南九州,四万十帯南帯のオリストストロ-ムIII.浅海堆積物の岩石学的特徴" 九州大学教養部研究報告. 28. 15-19 (1991)

Harutaka Sakai：“九州南部四万十带南部的Olistostorome III。浅海沉积物的岩石学特征”九州大学文学院研究报告28。15-19（1991）。

H.Sakai: "Gondwanas in the Nepal Himalaya. in,Tandon,S.K.,Pant,C.C.and Casshyap,S.M.eds;Sedimentary Basins of India" Nainital,India. 202-217 (1991)

H.Sakai：“尼泊尔喜马拉雅山的冈瓦纳。在，Tandon，S.K.，Pant，C.C.和 Casshyap，S.M.eds；印度沉积盆地”，印度奈尼塔尔。

H.Sakai: "Opening of the Japan Sea and formation of Misaki Olistostrome Belt---Timing and Genetic Inter-relationship" Monthly Earth,Extra Volume. No.5. 126-130

H.Sakai：“日本海的开放和三崎奥利斯托斯特罗姆带的形成——时间和遗传的相互关系”，地球月刊，额外卷。