{ "culture": "en-NZ", "name": "", "guid": "", "catalogPath": "", "snippet": "Classification of Mud, Sand and Gravel layers (this table) using the well-established (Folk et al. 1970) classification. Subtidal rocky reefs (this table) were incorporated. This classification provides a broad measure of hardness Mud \u2013 Rock.", "description": "

This layer shows a compilation of separate sediment layers (Mud, Sand, and Gravel) to portray a combined picture of bottom composition. Rock along with nine sediment types were initially defined according to the Folk sediment classification system based on the percentage of mud, sand, and gravel within cells (Folk et al., 1970). These were then grouped into mud, mixed sediment (mud + gravel and mud + gravel + sand), sand, and course sediment (gravel and gravel + sand) based on the figure below and are shown with rocky reef areas overlayed. Most of New Zealand\u2019s seafloor is covered by soft sediments, which tend to be characterized by less macrobiotic biodiversity than course sediment and rocky areas, although different key biogenic habitats can be found in each of these habitat types. Different configurations of grain sizes and materials are indicative of geologic history, hydrodynamic conditions, seafloor topography and biological activity and as a result host differing communities of organisms. <\/SPAN><\/P>

Source and reference:<\/SPAN><\/P>

\u201cThe Folk sediment triangle and the hierarchy of Folk classification (15, 6 and 4 classes, plus an additional class \u201crock and boulders,\u201d indicated by the arrow) used in the EMODnet Geology project.\u201d (Kaskela et al., 2019). <\/SPAN><\/P>

Folk RL, Andrews PB, Lewis DW. 1970. Detrital sedimentary rock classification and nomenclature for use in New Zealand. New Zealand Journal of Geology and Geophysics. 13:937\u2013968. DOI:10.1080/00288306.1970.10418211. https://www.tandfonline.com/doi/abs/10.1080/00288306.1970.10418211<\/SPAN><\/SPAN><\/P>

Kaskela, A. M., Kotilainen, A. T., Alanen, U., Cooper, R., Green, S., Guinan, J., et al. (2019). Picking up the pieces\u2013Harmonising and collating seabed substrate data for European maritime areas. Geosciences 9:84. doi: 10.3390/geosciences9020084 https://www.researchgate.net/publication/331094612_Picking_Up_the_Pieces-Harmonising_and_Collating_Seabed_Substrate_Data_for_European_Maritime_Areas<\/SPAN><\/SPAN><\/P>

References for sediment and rock layers included:<\/SPAN><\/P>

Bostock, H., C. Jenkins, K. Mackay, L. Carter, S. Nodder, A. Orpin, A. Pallentin, and R. Wysoczanski. 2019. Distribution of surficial sediments in the ocean around New Zealand/Aotearoa. Part A: continental slope and deep ocean. New Zealand Journal of Geology and Geophysics 62:1-23.<\/SPAN><\/SPAN><\/P>

Bostock, H., C. Jenkins, K. Mackay, L. Carter, S. Nodder, A. Orpin, A. Pallentin, and R. Wysoczanski. 2019. Distribution of surficial sediments in the ocean around New Zealand/Aotearoa. Part B: continental shelf. New Zealand Journal of Geology and Geophysics 62:24-45. https://www.tandfonline.com/doi/full/10.1080/00288306.2018.1523199<\/SPAN><\/SPAN><\/P>

Jenkins CJ. 1997. Building offshore soils databases. Sea Technology. 38(12):25\u201328.<\/SPAN><\/SPAN><\/P>

Smith, A. N., Duffy, C., Anthony, J., and Leathwick, J. R. 2013. Predicting the distribution and relative abundance of fishes on shallow subtidal reefs around New Zealand, Department of Conservation, Wellington, New Zealand<\/SPAN><\/SPAN><\/P>

<\/SPAN><\/P><\/DIV>", "summary": "Classification of Mud, Sand and Gravel layers (this table) using the well-established (Folk et al. 1970) classification. Subtidal rocky reefs (this table) were incorporated. This classification provides a broad measure of hardness Mud \u2013 Rock.", "title": "Sediment classification", "tags": [ "sediment classes", "mud", "gravel", "carbonate", "sand" ], "type": "", "typeKeywords": [], "thumbnail": "", "url": "", "minScale": 0, "maxScale": 0, "spatialReference": "", "accessInformation": "NIWA", "licenseInfo": "

Underlying limitations and uncertainties of each contributing map are inherent to this compilation (see Limitations and uncertainties section for each contributing map including mud, sand, gravel, and rock). Reducing the number of categories of sediment type was intended to reduce miscategorisation of individual cells.<\/SPAN><\/SPAN><\/P><\/DIV>" }