查詢結果分析
相關文獻
- Electron Microscopic Analyses of Greigite-Mackinawite Nodules near the Shallow Sulfate-Methane Transition Zone in Good Weather Ridge Sediments off Southwestern Taiwan
- Transmission Electron Microscopic Study of Authigenic Pyrrhotite in Methane Seep Sediments from the Yung-An Ridge Offshore Southwestern Taiwan
- 厭氧流體化床之生物膜顆粒層次模型及代謝活性試驗
- 鋼鋁片鍍層與化成塗膜表面分析技術之應用
- 硒化鎘奈米半導體晶體的合成及在薄膜製備上的應用
- Comparison of Upper Floret Development in Bisexual and Male Spikelets of Thuarea Involuta (Gramineae) with Scanning Electron Microscopy
- Treatment of High-Strength Nitrate Wastewater in Different Biological Denitrification Systems
- 黃槐(Cassia surattensis L.)雄蕊與雌蕊形態變異對結實之影響
- 場發射高分辨電子顯微鏡在揭示原子分辨率晶體缺陷上的應用
- 超導薄膜的電子顯微鏡研究
頁籤選單縮合
| 題 名 | Electron Microscopic Analyses of Greigite-Mackinawite Nodules near the Shallow Sulfate-Methane Transition Zone in Good Weather Ridge Sediments off Southwestern Taiwan=臺灣西南海域好景海脊沉積物鄰近淺深度硫酸鹽-甲烷過渡帶硫複鐵礦-四方硫鐵礦結核粒之電子顯微分析 |
|---|---|
| 作 者 | 黃克峻; 江威德; | 書刊名 | Collection and Research |
| 卷 期 | 37 2025.01[民114.01] |
| 頁 次 | 頁29-42 |
| 分類號 | 453.6 |
| 關鍵詞 | 硫複鐵礦; 四方硫鐵礦; 甲烷冷泉沉積物; 結核粒; 電子顯微鏡; Greigite; Mackinawite; Methane seep sediment; Nodule; Electron microscopy; |
| 語 文 | 英文(English) |
| DOI | 10.6693/CAR.202501_(37).0004 |
| 中文摘要 | 好景海脊鄰近硫酸鹽-甲烷過渡帶(海床以下深度200公分)底部甲烷冷泉沉積物中具 有相對單調礦物自生作用之硫化鐵結核粒,經掃瞄及穿透式電子鏡(SEM及TEM)分析, 以探討其可能之礦物形成與轉變次序。SEM觀察顯示硫複鐵礦為此類硫化鐵結核粒之主要組 成,通常包裹數個早期形成之黃鐵礦莓狀體,黃鐵礦晶粒間隙充填硫複鐵礦與四方硫鐵礦; 局部亦包裹部份氧化之殘存磁黃鐵礦,形成水合氧化鐵。於黃鐵礦莓狀體邊緣間隙,TEM 分析顯示硫複鐵礦生成沿 Grg方向拉長之次微米晶粒集合體,形成拼圖狀嵌合組織,其 Grg晶帶繞射圖呈現紅砷鎳礦微弱 2! h! 1! 繞射列,平行於硫複鐵礦 2! h! 1! 繞射列,同時硫複鐵礦 兩組對稱{111}Grg晶格條紋呈現顯著對比變化,暗示硫複鐵礦具有磁黃鐵礦(001)Po夾層,平行 於{111}Grg,此處未見四方硫鐵礦。另在黃鐵礦莓狀體中心內部,硫複鐵礦同樣具有磁黃鐵礦 夾層特徵,但與四方硫鐵礦形成兩類生長關係。第一類四方硫鐵礦構成具有不規則渾圓輪廓 之殘餘核心,為硫複鐵礦包裹,兩者具有 Grg // Mkw, {001}Grg // {001}Mkw, and {111}Grg // ~{011}Mkw之順構轉化衍生組構關係;第二類四方硫鐵礦生成延伸半自形微晶,與硫複鐵礦微 晶形成緻密交鎖組織,缺乏共同晶體方向或轉變組構,符合共沉澱交錯生長關係。硫化鐵結 核粒之可能礦物生成次序包含(1)早期形成黃鐵礦莓狀體,隨之沉澱磁黃鐵礦,可能生成 於淺部硫化帶之生痕孔洞;(2)隨後磁黃鐵礦及部份黃鐵礦氧化成水合氧化鐵,可能發生 於一個甲烷通量消退階段;(3)四方硫鐵礦沉澱充填大部份生痕孔洞空間及莓狀體黃鐵礦 晶粒間隙,可能為近期甲烷湧昇至淺部富反應性鐵沉積物,伴隨甲烷厭氧氧化作用之硫酸鹽 還原反應產物;(4)四方硫鐵礦硫化及部份氧化反應,透過界面耦合溶解-在沉澱過程, 順構轉化衍生形成硫複鐵礦。此等硫化鐵結核粒之相對單調礦物學變化註記沉積物近期非穩 定早成岩作用之紀錄。 四方硫鐵礦生成沿 Mkw延展之半自形個別晶體,與周圍硫複鐵礦晶體相接,或形成 不規則狀殘存晶體,為硫複鐵礦所包裹,兩者具有 Grg // Mkw, {001}Grg // {001}Mkw, and {111}Grg // ~{011}Mkw之順構轉化衍生組構關係。以上暗示一個可能礦物生成次序,包含(1) 早期形成黃鐵礦莓狀體,隨之沉澱磁黃鐵礦,可能生成於淺部硫化帶之生痕孔洞;(2)隨 後磁黃鐵礦部份氧化成水合氧化鐵,可能發生於一個甲烷通量消退階段;(3)四方硫鐵礦 沉澱充填生痕孔洞及莓狀體黃鐵礦晶粒間隙,可能為近期甲烷昇湧富鐵沉積物,甲烷厭氧氧 化作用伴隨硫酸鹽還原之反應產物;(4)四方硫鐵礦硫化及部份氧化反應,順構轉化衍生 形成硫複鐵礦。此等硫化鐵結核粒之礦物學註記好景海脊沉積物的一個近期非穩定早成岩作 用紀錄。 |
| 英文摘要 | Iron-sulfide nodules with relatively monotonous mineral authigenesis near the bottom of the sulfate-methane transition zone (SMTZ; 200 cmbsf) in methanic sediments from Good Weather Ridge (GWR) offshore southwestern Taiwan were analyzed by scanning (SEM) and transmission electron microscopic (TEM) methods to investigate possible formation and transformation sequences of ironsulfide minerals. SEM observations suggested greigite as the main constituent of these nodules, often surrounding a few early-formed pyrite framboids with interstices filled by a mixture of greigite and mackinawite, and occasionally enclosing relict pyrrhotite grains partially oxidized into hydrous iron oxides (HFOs). In areas near the edges of the pyrite framboids, TEM analyses indicated that greigite occurs as aggregates of submicrometer-sized crystals elongated along Grg, forming a jigsaw puzzlelike interlocking texture in the absence of mackinawite. The greigite displays faint NiAs 2! h! 1! hl reflection rows parallel to greigite 2! h! 1! hh reflections in the Grg zone, and invariably exhibits enhanced linear contrast parallel to symmetrically related {111}Grg lattice fringes, implying the presence of interlayered pyrrhotite (001)Po octahedral layers parallel to {111}Grg. In the interiors of the pyrite framboids, greigite is dominant and similarly exhibits interlayered features with pyrrhotite layers but occurs with mackinawite having two types of growth relationships. The first type of mackinawite occurs as a relict inclusion phase with irregularly rounded outlines enclosed by greigite, having a topotactic relationship of Grg // Mkw, {001}Grg // {001}Mkw, and {111}Grg // ~{011}Mkw, while the second type of mackinawite occurs as elongated subhedral microcrystals forming massive interlocking textures with greigite microcrystals without common orientations or transformation microstructures, consistent with a coprecipitation intergrowth relationship. A possible sequence of mineral formation in the nodules with less complexity includes (1) early formation of framboidal pyrite followed by precipitation of pyrrhotite in burrows in a shallow paleo-sulfuric zone, (2) subsequent oxidative alteration of pyrrhotite ± pyrite to HFOs, possibly during a period of methane recession, (3) mackinawite precipitation largely filling up burrows and interstices between framboidal pyrite microcrystals, possibly related to sulfate reduction associated with anaerobic oxidation of methane in reactive iron-rich sediments during a recent event of methane uprising, and (4) topotactic transformation of mackinawite to greigite through sulfidization and partial oxidation via interface-coupled dissolution-reprecipitation processes. The relatively monotonous mineralogical variations of the iron-sulfide nodules marks a record of recent non-steady-state diagenesis in the studied sediment. |
本系統中英文摘要資訊取自各篇刊載內容。