Standing Stocks and Spatial Distribution of Meiofauna on Deep-sea Sediment in an Environmental Impact Experiment of a Candidate Site
for Manganese Nodule Development, NE Pacific

Abstract. High-resolution optical and hydroacoustic seafloor data acquired in 2015 enabled the reconstruction of disturbance tracks of a past Benthic Impact Experiment that was conducted in 1989 in the Peru Basin in the course of former German environmental impact studies associated with manganese nodule mining. Based on this information, the disturbance level of the experiment regarding the plough impact and distribution and re-deposition of sediment from the evolving sediment plume was assessed qualitatively. Through this, the evolution over the 26 years of a number of the total 78 disturbance tracks could be analyzed which highlights the considerable difference between natural sedimentation in the deep-sea and sedimentation of a resettled sediment plume. Such plumes are seen as one of the most concerning impact associated with potential Mn-nodule mining. Problems in data processing became eminent while dealing with old data from the late 80s, at a time when GPS was just invented and underwater navigation was in an infant stage. However, even today the uncertainties of underwater navigation and the use of a variety of acoustical and optical sensors at different resolutions require detailed post-processing in terms of absolute geographic positioning to improve the overall accuracy of the data. In this study, a ship-based bathymetric map of the survey area was used as absolute geographic reference and a workflow was applied successfully resulting in the most accurate geo-referenced dataset of the DISCOL Experimental Area to date. The new field data were acquired with sensors attached to GEOMARs AUV Abyss and the 0.5 × 1° EM122 multibeam system of RV SONNE during cruise SO242 -1 while the old data first needed to be found and compiled before they could be digitized and properly georeferenced for the presented joined analyses.

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Flow Characteristics around DSSRS with Deep Sea Sediment in the Benthic Impact Experiment

Journal of the Korean Society of Mechanical Technology ◽

10.17958/ksmt.18.2.201604.192 ◽

2016 ◽

Vol 18 (2) ◽

pp. 192-199 ◽

Cited By ~ 1

Author(s):

채용배 ◽

임성진 ◽

허진석 ◽

LEE SANG HO

Keyword(s):

Deep Sea ◽

Flow Characteristics ◽

Deep Sea Sediment ◽

Impact Experiment

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The Economic Impacts of Pacific Ocean Deep-sea Manganese Nodule Development Project

Ocean and Polar Research ◽

10.4217/opr.2010.32.4.489 ◽

2010 ◽

Vol 32 (4) ◽

pp. 489-499 ◽

Cited By ~ 5

Author(s):

Seung-Hoon Yoo ◽

Dong-Won Jeong ◽

Se-Hun Park

Keyword(s):

Pacific Ocean ◽

Deep Sea ◽

Economic Impacts ◽

Manganese Nodule ◽

Development Project ◽

Nodule Development

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Relationship Between Manganese Nodule Distribution and Deep-Sea Sediment Properties in the Northeastern Pacific

Volume 7: Ocean Space Utilization; Ocean Renewable Energy ◽

10.1115/omae2012-83773 ◽

2012 ◽

Author(s):

Sang-Bum Chi ◽

Wonnyon Kim ◽

Cheong-Kee Park ◽

Chanmin Yoo ◽

Youngtak Ko ◽

...

Keyword(s):

Primary Productivity ◽

Deep Sea ◽

Regional Scale ◽

Chemical Properties ◽

Manganese Nodule ◽

Sediment Properties ◽

Deep Sea Sediment ◽

Sea Floor ◽

Sediment Types ◽

Northeastern Pacific

In order to identify a potential relationship between the spatial distribution of Mn-nodule and deep-sea sediment properties in the Clarion-Clipperton fracture zone of the northeastern Pacific, physico-chemical properties of deep-sea sediments and photos of sea-floor are analyzed. In general, sediment types in the area show dramatic changes with latitude. Compared to the middle sector (8–12°N) covered with biogenic siliceous sediments, the northern (16–17°N) and southern (5–6°N) areas are dominated by pelagic red clays and calcareous sediments, respectively. Such a difference in sediment types probably produces regional-scale variations in Mn-nodule occurrence with latitude (5–17°N) along longitude (131.5°W). According to the photographic examination, manganese nodules are well exposed on the sea floor in the latitude of >8°N. In connection with the dominant oceanic environment, such observation indicates that calcareous sediments cover the diagenic nodules due to higher primary productivity and sedimentation rate in the latitude of <8°N. In addition, sediments in the latitude of 8–12°N show relatively high shear strength. Considering the operation of miner and environmental effect, highly consolidated B2 and C1 areas (8–12°N), showing higher nodule contents and relatively lower primary productivity, are the most plausible site for commercial mining.

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Preliminary Economic Feasibility Study of Ferromanganese Nodule Mining by Mechanical Lifting and Small-Scale Collectors

Minerals ◽

10.3390/min11121389 ◽

2021 ◽

Vol 11 (12) ◽

pp. 1389

Author(s):

Sup Hong ◽

Hyung-Woo Kim ◽

Tae-Kyung Yeu ◽

Rei Arai ◽

Tetsuo Yamazaki

Keyword(s):

Environmental Impact ◽

Deep Sea ◽

Economic Feasibility ◽

Small Scale ◽

Ferromanganese Nodule ◽

Deep Sea Sediment ◽

Metal Source ◽

Environmental Considerations ◽

Bulk Scale ◽

Nodule Mining

Ferromanganese nodules have been recognized as a potential future metal source for over 50 years. Many research and development efforts have been conducted by many organizations. Most of the efforts have been concentrated into the mining technologies especially for hydraulic lifting through riser pipes with bulk-scale nodule collector. However, no commercial mining venture exists. Uncertainty in the economy of nodule mining is considered to be the reason for this. In order to improve the economy, a mining subsystem based on mechanical lifting and small-scale collectors is proposed and the preliminary economic feasibility is examined in this study. The benefit was at a favorable level compared with that using hydraulic lifting with bulk-scale collector. From the viewpoint of environmental impact assessment, environmental considerations of deep-sea sediment plume are explained.

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