Control of Deep Currents on Sediment and Cold-Water Coral Distribution on the Northern Manihiki Plateau
Advanced Search
Select up to three search categories and corresponding keywords using the fields to the right. Refer to the Help section for more detailed instructions.

Search our Collections & Repository

For very narrow results

When looking for a specific result

Best used for discovery & interchangable words

Recommended to be used in conjunction with other fields

Dates

to

Document Data
Library
People
Clear All
Clear All

For additional assistance using the Custom Query please check out our Help Page

i

Control of Deep Currents on Sediment and Cold-Water Coral Distribution on the Northern Manihiki Plateau

Filetype[PDF-4.97 MB]



Details:

  • Journal Title:
    Frontiers in Marine Science
  • Personal Author:
  • NOAA Program & Office:
  • Description:
    High-definition video surveys of remotely-operated vehicle (ROV) dives from the NOAA’s Mountains in the Deep 2017 expedition (EX1705) along volcanic ridges and seamounts of the Manihiki Plateau coupled with multibeam bathymetry data and water column profiles, reveal no or minimal sediment cover on the basaltic edifice, but variable amounts of cold-water corals on ferromanganese-encrusted basaltic rocks. Coarse sediment, however, accumulates in crevasses and sedimentary ripples testify the existence of currents in the area. Collectively, these observations illustrate the strong influence of deep currents on the surficial geology and cold-water coral distribution at ∼2,000 m water depths. Dive transects along two basaltic seamounts show stark differences of sedimentary features and cold-water coral distribution. On the ridges of “Te Kawhiti” (water depth: 2,089–2,220 m), basaltic slabs, and cold-water corals are far more abundant in comparison to the slope of a mesa in “Te Tuku” (water depth: 2,440–2,495 m). The increased abundance on “Te Kawhiti” is due to the exposure of “Te Kawhiti” to Lower Circumpolar Deep Water that sweeps the summit of the ridges as indicated by frequent ripples observed in between the basaltic rocks. The currents are strong enough to sweep fine-grained sediments away, leaving coarse-grained sediments behind, inducing the formation of ferromanganese crust on the basaltic rocks. Both dive sites are below the high-Mg calcite saturation horizon, and as a result, the cold-water coral community is dominated by Isididae, which can build a high-Mg calcite skeleton in water undersaturated in regards to high-Mg calcite.
  • Keywords:
  • Source:
    Front. Mar. Sci., 05 May 2020
  • DOI:
  • Document Type:
  • Place as Subject:
  • Rights Information:
    CC BY
  • Compliance:
    Submitted
  • Main Document Checksum:
  • Download URL:
  • File Type:

Supporting Files

  • No Additional Files
More +

You May Also Like

Checkout today's featured content at repository.library.noaa.gov

Version 3.27.1