Regional variation of manganese nodule facies on the Wake-Tahiti transect: Morphological, chemical and mineralogical study
Regional variation of manganese nodule facies on the Wake-Tahiti transect: Morphological, chemical and mineralogical study
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威克-塔希提样带锰结核相的区域变化：形态、化学和矿物学研究
DOI：
10.1016/0025-3227(83)90007-5
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发表时间：
1983
期刊：
影响因子：
2.9
通讯作者：
A. Usui
中科院分区：
文献类型：
--
作者：
A. Usui
在日本地质调查局的“Hakurei-Maru”号考察船进行的GH 80 -1巡航（1980年1月至3月）期间，在从Wake到Tahiti的4000 km长的断面上发现了锰结核相的显著区域变化。使用箱式取样器、自由落体抓斗和活塞取样器进行了190多次海底取样和120次海底摄影，发现了三种典型的结核相，每种结核相都延伸数百公里。在北方中太平洋海盆和中太平洋山脉地区（沸石/远洋粘土表层沉积物），主要是盘状至不规则形状的光滑表面结核。它们由内部破碎的δ-MnO 2组成的老结核和周围2-5 mm厚的δ-MnO 2层和10 μ m厚的δ-MnO 2层组成。Mn、Fe和Cu+ Ni含量较低（平均值：1.4和0.85重量%）与矿物学相符在中太平洋海盆中部至南部（硅质粘土或软泥表面沉积物），主要是具有同心结构的球形和粗糙表面结核。每一同心层由10 μ m组成，产生高Mn Fe和Cu+ Ni（平均值：4.1和2.41重量%）。在Penrhyn盆地（沸石粘土表面沉积物），分布着内部结构简单的球形至盘状光滑表面结核。它们主要由δ-MnO 2组成，因此Mn Fe和Cu+ Ni含量较低（平均值：1.3和0.85wt.%）。覆盖着厚厚的石灰质沉积物的马尼希基高原是一个贫瘠的地区。这些区域性的表面和内部结构及化学特征的差异主要是由于两种铁锰矿物的优先生长。矿物的区域变化模式及其与表层沉积物变化的密切关系符合矿物的两条供给途径模式。形成粗糙表面的10 Å锰氧化物主要发育在中太平洋盆地中南部硅质沉积物的成岩作用下的表层沉积物中，而δ-MnO 2则是通过上覆底层沃茨水直接供应金属元素而发育的，形成光滑的表面结核在中太平洋盆地和彭林盆地的北方。
During the GH80-1 cruise of RV “Hakurei-Maru”(January to March 1980) conducted by the Geological Survey of Japan, a significant regional variation of manganese nodule facies was found on the 4000 km long transect from Wake to Tahiti. More than 190 bottom samplings and 120 sea-bed photography using box corer, free-fall grab, and piston corer, revealed three characteristic nodule facies, each extending over hundreds of kilometers. In the northern Central Pacific Basin and the Mid-Pacific Mountains area (zeolitic/pelagic clay surface sediment), discoidal to irregular shaped smooth surface nodules are dominant. They consist of inner fragmented older nodules composed of δ-MnO 2 and surrounding 2–5 mm thick layers of δ-MnO 2 and 10 Å manganate. Mn Fe and Cu+ Ni are low (averages: 1.4 and 0.85 wt.%) consistent with mineralogy. In the central to southern Central Pacific Basin (siliceous clay or ooze surface sediment) spherical and rough surface nodules with concentric structure predominate. Each concentric layer consists of 10 Å manganate, yielding high Mn Fe and Cu+ Ni (averages: 4.1 and 2.41 wt.%). In the Penrhyn Basin (zeolitic clay surface sediment), spherical to discoidal shaped smooth surface nodules of simple internal structure are distributed. They consist mostly of δ-MnO 2 and consequently Mn Fe and Cu+ Ni are low (averages: 1.3 and 0.85 wt.%). The Manihiki Plateau covered with thick calcareous sediments is a barren area. These regional variation in surface and internal structures and chemical characteristics are principally due to preferential growths of the two ferromanganese minerals. The mode of regional variation of the minerals and its close relationship to surface sediments variability are consistent with the two supply route model of these minerals. The 10 Å manganate forming rough surface dominantly developed within surface sediments as a result of diagenesis of siliceous sediments in the central and southern Central Pacific Basin, whereas δ-MnO 2 develops through direct supply of metal elements from the overlying bottom waters forming smooth surface nodules in the northern Central Pacific Basin and Penrhyn Basin.