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1.
深海浅地层剖面特征及其与多金属结核富集度的关系   总被引:1,自引:0,他引:1  
对东太平洋 C C 区内 1 万多公里的浅地层剖面探测资料进行了统计分析, 并对深海浅地层剖面特征及其与多金属结核丰度的关系作了研究, 结果表明: 多金属结核的富集度与海底声反射率呈正比关系, 影响和控制结核丰度的主要因素是海底地形。一般透明层愈厚, 结核愈富集, 但不是对应关系; 层状层或散射层发育, 则多金属结核富集, 反之则不富集  相似文献   

2.
深海浅地层剖面特及其与多金属结核富集度的关系   总被引:2,自引:1,他引:1  
对东太平洋CC区内1万多公里的浅地层剖面探测资料进行了统计分析,并对深海浅地层剖面特征及其与多金属结核丰度的关系作了研究。结果表明:Q我金属结核的富集度与海镀声反经呈正比关系,影响和控制结核丰度的主要因素是海底地形。一般透明层愈厚,结核愈富集,但不是对应关系;层状层或散射层发育,则多金属结核富集,反之则不富集。  相似文献   

3.
在综合分析航次调查资料的基础上,总结了中太平洋海盆多金属结核的矿产资源特征与分布规律,并与CC区中国多金属结核开辟区结核特征进行对比。结果发现:CP区多金属结核以S型水成成因为主,具有较高的丰度与覆盖率,但品位较低;而CC区结核S型(西区)、S+R型、R型(东区)三者均有,以混合成因和成岩成因为主,尽管丰度、覆盖率稍低,但品位较高。多金属结核中锰相矿物差异、表层沉积物类型及南极底流的影响是造成两区多金属结核差异的主要因素。  相似文献   

4.
1994年4-11月,国家海洋局组织和实施了DY85-4航次中国开辟区(太平洋CC区)多金属结核(下简称结核)勘探,海上勘查历时225d,勘查面积达65×103km2,其中,用重力、磁力和单道地震等方法对测区进行了地球物理调查。结果表明,火山和浅层侵入体是提供给核生成的重要物质来源。区域性的沉积间断是造成结核丰度偏高的重要因素。断块活动强烈的地区,断裂活动有利于金属元素在海底的富集。不同时代形成的海底,地幔原岩在成分上的差异或在洋壳形成过程中构造活动的差异,对结核的形成有着一定的控制因素。而上述地质构造活动,在地球物理特征上都有着明显的反映。由此可见,地球物理特征与结核的形成和富集规律有着明显的相关关系。  相似文献   

5.
DY85—1航次(1992年5月24日—11月21日)由地矿部广州海洋地质调查局利用《海洋四号》船实施的我国“八五”期间在东太平洋我国申请区的开辟区(东太平洋海盆西部,夏威夷岛东南海域,其地理坐标大致是8°52.5′—11°22.5′N,151°7.5′—153°22.5′W)内进行的第一个航次调查,也是我国以中国大洋矿产资源研究开发协会(简称大洋协会)的名义,向联合国国际海底管理局筹委会申请作为先驱投资者并获批准后实施的首次调查,其目的是在“七五”调查工作的基础上,对开辟区西部进行进一步的勘探,圈定出区内富矿区,计算出多金属结核的资源量,对多金属结核资源进行评价,同时为“海洋”地质科学研究和采矿,选矿与冶炼试验研究采集样品,具体任务有: 1.通过地质取样、海底照相、多频探测和其它地球物理方法的调查,以及结核样品的测试分析,查明多金属结核类型、形状、丰度、覆盖率、品位及其分布规律,计算出资源量。 2.通过较详细的测深资料,查清区内地形、地貌特征,以及区内结核分布(丰度、品位变化)与宏观、微观地形,地貌、水深的关系,依照调查精度,圈出坡度大于5°的地形障碍物。 3.采集足够的结核和沉积物样品,查清区内沉积物类型、结构、分布特征及其工程地质特征。  相似文献   

6.
本文以DY85-4 航次在东太平洋的调查为基础,概述了多金属结核在东西两海区的差异;分析了影响这种差异的因素;着重探讨了多金属结核的丰度、品位、覆盖率、Mn/Fe、与伴生沉积物、断裂带、火山、侵入岩的关系。发现造成两区结核差异的因素很多,但起主控作用的是断块、火山、岩浆、热液等活动所带来的物质及对海底物理化学环境的影响。  相似文献   

7.
东太平洋不同海域多金属结核差异的主控因素   总被引:2,自引:0,他引:2  
本文以DY85-4航次在东太平洋的调查为基础,概述了多金属结核在东西两海区的差异;分析了影响这种差异的因素;着重探讨了多金属结核的丰度,品位,覆盖率,Mn/Fe,与伴生沉积物,断裂带,火山,侵入岩的关系。发现造成两区结核差异的因素很多,但起主控作用的是断块,火山,岩浆,热液等活动所带来的物质及对海底物理化学环境的影响。  相似文献   

8.
地形坡度对多金属结核分布的控制作用   总被引:3,自引:3,他引:3  
选取我国东太平洋多金属结核开辟区内的一个区域作为研究区,利用人工神经网络中应用最为广泛的BP网络,建立控制多金属结核分布的地质因素与多金属结核分布之间的映射关系,探讨地形坡度对多金属结核分布的控制作用.结果表明,在经度、纬度、水深、坡度四个因素中,坡度对结核分布影响程度最大;多金属结核主要分布于坡度小于5°的地方;当坡度小于5°时,丰度与地形坡度呈正相关,品位与地形坡度呈负相关,丰度与品位呈负相关;品位与坡度似呈指数关系,坡度增大,品位降低.  相似文献   

9.
人工神经网络在多金属结核研究中的应用   总被引:8,自引:3,他引:5  
王英  金翔龙 《海洋学报》1998,20(5):83-89
本文通过对太平洋CC区多金属结核成矿背景的综合分析,利用人工神经网络随机BP算法,建立能够反映控矿因素的地质因子与结核分布参数间关系的人工神经网络模型,用于研究海底多金属结核的分布。本文对BP算法加以改进,提高了BP网络的收敛速度,加强了BP网络的学习和记忆功能,开发出人工神经网络的软件包,该软件包能够快速估算矿区内每个位置结核的丰度值,且具有较高的容错性。  相似文献   

10.
大洋多金属结核资源量计算和资源评价方法探讨   总被引:2,自引:3,他引:2  
张富元 《海洋学报》1995,17(4):86-93
本文对大洋多金属结核资源量计算中所涉及到的各种参数,包括矿区面积、结核丰度、结核品位、结核含水率和海底障碍物进行了较详细的论述;确定了多金属结核资源量计算方法及其选择依据,并对算术平均法和加权平均法的计算结果进行了对比;针对太平洋CC区(Clarion-Clipperton Zone)两种不同成因的多金属结核矿区,着重对结核水平分布连续性、单位面积资源量、结核丰度和品位的稳定性作了定量分析,并利用标准差对结核丰度和品位的变化作了统计分析.最后根据这些分析结果对多金属结核矿区进行了综合性资源评价.文中尚强调镍等量在多金属结核资源评价中的重要作用.  相似文献   

11.
In order to develop the mineral resources contained in manganese nodules of the deep sea, the Korea Ocean Research & Development Institute (KORDI) has explored the area allocated by the United Nations in the Clarion-Clipperton Fracture Zone in the northeastern Pacific. During research cruises, the seabed surface was photographed every 30 s by the KORDI Deep Tow Imaging System (DTIS). Features such as the coverage and size distribution of manganese nodules on the photographs serve as the essential information to determine the potential mining areas. This article presents (semi)automatic procedures to extract the useful features from the photographs of the seabed surface using digital image processing techniques. The 35-mm films are first digitized by the film scanner. The depth information written on the film is then recognized to compensate for distortions due to nonuniform illumination. The nodule areas on the digitized image are recognized and separated from the background based on the characteristics of the nodules. The nodule coverage and distribution of nodule diameters are then calculated from the processed image. The proposed technique has been applied to sample photographs of the seabed surface. Experimental results indicate that the technique could be utilized as an efficient tool to process the massive collection of photographs of the seabed surface.  相似文献   

12.
The deep ocean floor between the Clarion and Clipperton fracture zones (NE equatorial Pacific) has the highest known manganese nodule abundance in the world oceans. A detailed analysis of MR1 (Mapping Researcher 1, 11-12 kHz) sonar images and free-fall grab data in the Korean manganese nodule field areas reveals a close relationship between side-scan sonar characteristics of the seafloor and manganese nodule abundance. Eight sonar facies are identified based on back-scattering intensity and distribution patterns. These sonar facies can be interpreted as (1) volcanic seamounts (facies I-1), (2) bounding faults of abyssal hills (facies I-2 and II-1), (3) lava flows or volcanoclastic mass-flow deposits around the volcanic seamounts (facies I-3 and II-2), (4) crests of abyssal hills (facies II-1), (5) abyssal troughs between abyssal hills (facies III-1), (6) relatively flat areas (facies II-3 and III-2). In the areas where facies II-1 (abyssal hill crests with thin sediment cover) and II-3 (relatively flat areas draped by thin sediments) are dominant, manganese nodules occur abundantly. In contrast, zones comprising facies III-1 (abyssal troughs with thick sediment cover) and III-2 (relatively flat areas covered by thick sediments) are characterized by low abundance of manganese nodules. This relationship between distribution of sonar facies and manganese nodule abundance implies that (1) the qualitative difference in acoustic reflectivity of long-range side-scan sonar with some ground truth data is useful for regional assessment of manganese nodule occurrence over wide areas in a reasonable time, and (2) seafloor topography and sediment thickness are important controlling factors for regional occurrences of manganese nodules.  相似文献   

13.
The deep ocean floor between the Clarion and Clipperton fracture zones (NE equatorial Pacific) has the highest known manganese nodule abundance in the world oceans. A detailed analysis of MR1 (Mapping Researcher 1, 11–12?kHz) sonar images and free-fall grab data in the Korean manganese nodule field areas reveals a close relationship between side-scan sonar characteristics of the seafloor and manganese nodule abundance. Eight sonar facies are identified based on back-scattering intensity and distribution patterns. These sonar facies can be interpreted as (1) volcanic seamounts (facies I-1), (2) bounding faults of abyssal hills (facies I-2 and II-1), (3) lava flows or volcanoclastic mass-flow deposits around the volcanic seamounts (facies I-3 and II-2), (4) crests of abyssal hills (facies II-1), (5) abyssal troughs between abyssal hills (facies III-1), (6) relatively flat areas (facies II-3 and III-2). In the areas where facies II-1 (abyssal hill crests with thin sediment cover) and II-3 (relatively flat areas draped by thin sediments) are dominant, manganese nodules occur abundantly. In contrast, zones comprising facies III-1 (abyssal troughs with thick sediment cover) and III-2 (relatively flat areas covered by thick sediments) are characterized by low abundance of manganese nodules. This relationship between distribution of sonar facies and manganese nodule abundance implies that (1) the qualitative difference in acoustic reflectivity of long-range side-scan sonar with some ground truth data is useful for regional assessment of manganese nodule occurrence over wide areas in a reasonable time, and (2) seafloor topography and sediment thickness are important controlling factors for regional occurrences of manganese nodules.  相似文献   

14.
Chemical and X-ray analyses were performed on the fifteen manganese nodules collected from the Pacific Ocean floor. The results were discussed compared with the previous data on the manganese nodules. Minerals were found to be todorokite, δ-MnO2 and other silicates, montmorillonite, illite, phillipsite and α-SiO2. Average composition shows that copper is concentrated on the deep sea nodules more than the shallow ones, and that the todorokite rich nodules contain more copper and nickel than the δ-MnO2 rich ones. The analyses of fresh water iron-manganese precipitates by bacterial activity suggest that biological process is one of the important factors on the genesis of the sedimentary iron-manganese deposits, including the manganese nodule. The Institute of Physical and Chemical Research  相似文献   

15.
A high level of confidence in resource data is a key prerequisite for conducting a reliable economic feasibility study in deep water seafloor mining. However, the acquisition of accurate resource data is difficult when employing traditional point-sampling methods to assess the resource potential of polymetallic nodules, given the vast size of the survey area and high spatial variability in nodule distribution. In this study, we analyzed high-resolution acoustic backscatter intensity images to estimate nodule abundance and increase confidence levels in nodule abundance data. We operated a 120 kHz deep-towed sidescan sonar (DSL-120) system (1×1 m resolution) across a 75 km2 representative area in the Korean Exploration Area for polymetallic nodules in the Northeastern Equatorial Pacific. A deep-towed camera system was also run along two tracks in the same area to estimate the abundance of polymetallic nodules on the seafloor. Backscatter data were classified into four facies based on intensity. The facies with the weakest and strongest backscatter intensities occurred in areas of high slope gradient and basement outcrops, respectively. The backscatter intensities of the two other facies correlated well with the nodule abundances estimated from still-camera images. A linear fit between backscatter intensity and mean nodule abundance for 10 zones in the study area yielded an excellent correlation (r2 = 0.97). This allowed us to compile a map of polymetallic nodule abundance that shows greater resolution than a map derived from the extrapolation of point-sampling data. Our preliminary analyses indicate that it is possible to greatly increase the confidence level of nodule resource data if the relationship between backscatter intensity and nodule abundance is reliably established. This approach has another key advantage over point sampling and image analyses in that detailed maps of mining obstacles along the seafloor are produced when acquiring data on the abundance of polymetallic nodules. The key limitation of this work is a poor correlation between nodule coverage, as observed from photographs, and nodule abundance. Significant additional ground truth sampling using well located box cores should be completed to determine whether or not there is a real correlation between the backscatter and abundance.  相似文献   

16.
为探讨东太平洋CC区多金属结核中富钡镁锰矿细脉蛋白石层的成因机制,利用矿相显微镜、电子探针和ICP-OES,对蛋白石层及其周围铁锰氧化物进行了显微结构特征和化学成分特征的研究。结果表明:高反射率矿物结晶程度较好,主要由MnO组成,具有高Mn低Fe的特征,为成岩成因的钡镁锰矿。中反射率矿物结晶程度较差,主要由MnO和FeO组成,为水成成因的水羟锰矿。低反射率矿物为一种半透明矿物,主要由SiO2组成,为生物成因的蛋白石。根据钡镁锰矿、水羟锰矿和蛋白石的成因机制,为蛋白石层及其内部钡镁锰矿细脉的形成过程建立了一个模型,共分为5个生长阶段:第1阶段,结核呈半埋藏状态在氧化环境中形成水羟锰矿;第2阶段,结核呈半埋藏状态接受SiO2胶体的沉淀作用形成蛋白石层;第3阶段,结核呈半埋藏状态在氧化环境中形成水羟锰矿的同时,其成岩作用和蛋白石的脱水作用使蛋白石层中产生大量的裂缝;第4阶段,结核呈埋藏状态在弱氧化-还原环境中发生交代作用和重结晶作用形成钡镁锰矿;第5阶段,结核呈半埋藏状态形成水羟锰矿。  相似文献   

17.
Abstract

Seafloor morphology and ferromanganese nodule occurrence were studied using a multibeam side scan sonar (SeaBeam, 2000) and a deep-sea camera system in the Korea Deep-sea Environmental Study (KODES) area, northeast equatorial Pacific. Seafloor morphology and nodule abundance are highly variable even in this small study area. The NNE-SSW oriented hills are parallel and about 100–200 m high. Valleys are very flat-floored, while hilltops are rugged with depressions of tens of meters. Cliffs to about 100 m bound the valleys and the hills. The study area can be classified into three types based both on nodule occurrence and seafloor morphology, mostly G- and B-types and some M-type. G-type is characterized by high nodule abundance, ubiquitous bioturbation, and flat seafloor morphology, while B-type is characterized by irregular-shaped nodules, variable nodule abundance, occurrence of giant nodules and sediment lumps, rugged bottom morphology with depressions, and white calcareous surface sediments. Medium nodule abundance and a generally flat seafloor characterize M-type. G-type occurs mostly in the valley regions, while B-type is on the hilltop areas. M-type is located between the hilltop and the valley. Tectonic movement of the Pacific plate resulted in the elongated abyssal hills and cliffs. The rugged morphology on hilltops resulted from erosion and redistribution of surface siliceous sediments on hilltops by bottom currents, outcropping of underlying calcareous sediments, and dissolution of the carbonate sediments by corrosive bottom water undersaturated with CaCO3. Sediment eroded from the hills, which is relatively young and organic-rich, is deposited in the valleys, and diagenetic metal supply to manganese nodules in the valley area is more active than on the hills. We suggest that tectonic movement ultimately constrains morphology, surface sediment facies, bottom currents and sediment redistribution, bioturbation, thickness of the sedimentary layer, and other conditions, which are all interrelated and control nodule occurrence. The best potential area for mining in the study area is the G-type valley zones with about 3–4 km width and NNW-SSE orientation.  相似文献   

18.
Methods developed for quantitative estimation of seafloor features from seabed photographs and their application for estimation of nodule sizes, coverage, abundance, burial, sediment thickness, extent of rock exposure, density of benthic organisms, and their lebensspuren have been presented. Digitization of the photographs shows variable nodule size (< 1 to 10 cm), coverage (< 1 to 75%) and abundance (< 1 to 20 kg/m2). Nodule population is inversely proportional to the coverage of the sediment (10–100%) and its thickness (0 to > 10 cm), which causes differential burial (0–100%) of nodules. Correlation between nodule parameters (diameter and coverage) in the photographs and grab recovery is used to evolve empirical relationships for estimating nodule abundance in different seabed settings. The rock outcrops (basalts) with a coverage of 6–100% are the sources of nuclei for the nodules, the distribution of which is controlled by the local topography. Higher concentrations of nodules are observed along the slopes, followed by the crests of seamounts, and are lowest in the valleys and plains. A population density of 6–7 benthic organisms per 100 m2 belonging to 7 different phyla is observed, with a high frequency of lebensspuren (4–12 traces/m2) in association with nodules. Estimation of these parameters can be used as important inputs in the design of the nodule collector, as it will have to encounter a variety of seafloor conditions, such as patchy nodule distribution, rock outcrops, steep slopes, and frequent microtopographic changes, as well as benthic life. The distribution and relation of various features with one another can also be used to understand the possible impact of nodule mining on the seabed. Estimates show that for a yield of 3 million tonnes of nodules per year, the volume of sediment disturbed will be between 200 × 107 and 500 × 107 m3over an area of 300–600 km2, depending upon the average abundance of nodules. Hence, the nodule collector will have to be a self‐propelled system, with photographic and acoustic sensors, to enable selective mining and avoid unfavorable areas.  相似文献   

19.
Abstract

The morphological features associated with Co-rich manganese deposits, the size variations of nodules, and the occurrence of different substrates have been analyzed, to evaluate the influence of various seabed slope angles on the distribution of these features. The coverage and size of the crusts depend on their surface morphology and seabed topography, resulting in cobble-type, lineated, or step-like outcrops. Small nodules (1–4 cm in diameter) dominate all seabed slopes, with a few locations having nodules ranging from 1 to 8 or 1 to 10 cm. Sediments invariably occur as substrates for nodules and as cover for crusts, their coverage being inversely proportional to that of the nodules and crust outcrops.

Steeper seafloor areas have large crust outcrops exposed with no or few nodules and sediments associated with them. The intermediate slopes have a combination of nodules, sediments, and crusts in various proportions, depending on topography and gradient. Large-scale nodule occurrences, followed by sediment fields and crust outcrops on seabed slopes of < 3°, 3–7°, and > 15°, respectively, represent typical morphological distribution zones of the Co-rich manganese deposits on a seamount in the central Pacific Ocean. A transition zone between nodule-dominated fields and large crust outcrops occurs for slopes from 7° to 15°. This detailed study on distribution of Co-rich deposits gives a better understanding for purposes of their exploitation.  相似文献   

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