| snippet:
|
The percent gravel layers for the region were developed from >30,000 raw sediment sample data compiled in dbseabed (Jenkins et al. 1997), which were then imported into ArcGIS and interpolated using Inverse Distance Weighting (Bostock, pers comm) |
| summary:
|
The percent gravel layers for the region were developed from >30,000 raw sediment sample data compiled in dbseabed (Jenkins et al. 1997), which were then imported into ArcGIS and interpolated using Inverse Distance Weighting (Bostock, pers comm) |
| accessInformation:
|
NIWA |
| thumbnail:
|
|
| maxScale:
|
0 |
| typeKeywords:
|
[] |
| description:
|
<DIV STYLE="text-align:Left;font-size:12pt"><P STYLE="margin:0 0 11 0;"><SPAN><SPAN>Gravel makes up seafloor sediments with larger grain sizes than those considered to be sand (>2 mm to 4 mm). Gravel types and percentages can indicate geologic histories as well as types of communities likely to be present. Gravel can vary in carbonate content and form a more stable substrate allowing organisms to attach and grow into diverse ecological communities including several types of biogenic habitats such as some kelp forests and algal meadows, as well as rhodolith beds, bryozoan and sponge gardens, especially in areas of rhodolith and shell-derived gravel, and even sea pens in areas of finer gravel. The percent gravel layers for the region were developed from >30,000 raw sediment sample data and compiled (Jenkins et al. 1997), then imported into ArcGIS and interpolated using Inverse Distance Weighting (Bostock et al., 2019). </SPAN></SPAN></P><P STYLE="margin:0 0 11 0;"><SPAN><SPAN /></SPAN></P><P STYLE="margin:0 0 11 0;"><SPAN STYLE="font-weight:bold;">References:</SPAN></P><P><SPAN><SPAN>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 </SPAN></SPAN><SPAN STYLE="font-weight:bold;"><SPAN>62</SPAN></SPAN><SPAN><SPAN>:1-23.</SPAN></SPAN></P><P><SPAN><SPAN /></SPAN></P><P STYLE="margin:0 0 11 0;"><SPAN><SPAN>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 </SPAN></SPAN><SPAN STYLE="font-weight:bold;"><SPAN>62</SPAN></SPAN><SPAN><SPAN>:24-45. </SPAN></SPAN><A href="https://www.tandfonline.com/doi/full/10.1080/00288306.2018.1523199" STYLE="text-decoration:underline;"><SPAN STYLE="text-decoration:underline;"><SPAN>https://www.tandfonline.com/doi/full/10.1080/00288306.2018.1523199</SPAN></SPAN></A></P><P STYLE="margin:0 0 11 0;"><SPAN><SPAN>Jenkins CJ. 1997. Building offshore soils databases. Sea Technology. 38(12):25–28.</SPAN></SPAN></P><P STYLE="margin:0 0 11 0;"><SPAN><SPAN /></SPAN></P><P STYLE="margin:0 0 11 0;"><SPAN><SPAN /></SPAN></P></DIV> |
| licenseInfo:
|
<DIV STYLE="text-align:Left;font-size:12pt"><P STYLE="margin:0 0 11 0;"><SPAN><SPAN>Sampling is biased against larger gravel grainsizes therefore shell, pebble and cobbles, which are likely underrepresented in this dataset resulting in more uncertainty compared with those of mud and sand. Seafloor sediments will continually be in a state of flux due to floods, storms, earthquakes, volcanic and human activities, however these maps have been developed from a large number of samples (over 23,000) over a relatively long time frame (over 60 years), though some regions remain under-sampled and are therefore less well characterised, particularly the continental shelf regions of East Cape, southern Wairarapa, Fiordland and the west coast of the South Island (Bostock et al., 2019b). Key issues are lack of sampling data in many regions of the EEZ, and extrapolation outward from solitary point records for a large portion of the EEZ (Bostock 2019a).</SPAN></SPAN></P></DIV> |
| catalogPath:
|
|
| title:
|
Gravel |
| type:
|
|
| url:
|
|
| tags:
|
["Gravel","sediment classification","marine environment"] |
| culture:
|
en-NZ |
| name:
|
|
| guid:
|
|
| minScale:
|
0 |
| spatialReference:
|
|