OR/14/015 South-west Deeps (West) - Revision history

Dbk at 09:21, 6 August 2015

2015-08-06T09:21:09Z

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	{{OR/14/015}}		{{OR/14/015}}
	==Data==		==Data==
	The data used for the South-west Deeps (West) MCZ (SWDW) are particle size analyses from the verification survey carried out by Cefas in 2013 (McIlwaine, 2013<ref name="McIlwaine">MCILWAINE, P. 2013 South-West Deeps (West) recommended Marine Conservation Zone (rMCZ) Survey Report: C5785H. Issue date: 24 July 2013. </ref>). The data were collected by 0.1 m<~~ref~~>2</~~ref~~> Hamon grab from 208 locations on a pre-planned survey grid. Exploratory analysis found no duplicate locations in this data set. This is a sizeable data set to support a spatial analysis, so as described for Swallow Sand in section 2.1 above, no attempt was made to supplement these data with others from the BGS archive.		The data used for the South-west Deeps (West) MCZ (SWDW) are particle size analyses from the verification survey carried out by Cefas in 2013 (McIlwaine, 2013<ref name="McIlwaine">MCILWAINE, P. 2013 South-West Deeps (West) recommended Marine Conservation Zone (rMCZ) Survey Report: C5785H. Issue date: 24 July 2013. </ref>). The data were collected by 0.1 m<sup>2</sup> Hamon grab from 208 locations on a pre-planned survey grid. Exploratory analysis found no duplicate locations in this data set. This is a sizeable data set to support a spatial analysis, so as described for Swallow Sand in section 2.1 above, no attempt was made to supplement these data with others from the BGS archive.

	===Exploratory data analysis and transformation===		===Exploratory data analysis and transformation===

Dbk at 09:20, 6 August 2015

2015-08-06T09:20:47Z

← Older revision		Revision as of 10:20, 6 August 2015
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	{{OR/14/015}}		{{OR/14/015}}
	==Data==		==Data==
	The data used for the South-west Deeps (West) MCZ (SWDW) are particle size analyses from the verification survey carried out by Cefas in 2013 (McIlwaine, 2013<ref name="McIlwaine">MCILWAINE, P. 2013 South-West Deeps (West) recommended Marine Conservation Zone (rMCZ) Survey Report: C5785H. Issue date: 24 July 2013. </ref>). The data were collected by 0.1 m2 Hamon grab from 208 locations on a pre-planned survey grid. Exploratory analysis found no duplicate locations in this data set. This is a sizeable data set to support a spatial analysis, so as described for Swallow Sand in section 2.1 above, no attempt was made to supplement these data with others from the BGS archive.		The data used for the South-west Deeps (West) MCZ (SWDW) are particle size analyses from the verification survey carried out by Cefas in 2013 (McIlwaine, 2013<ref name="McIlwaine">MCILWAINE, P. 2013 South-West Deeps (West) recommended Marine Conservation Zone (rMCZ) Survey Report: C5785H. Issue date: 24 July 2013. </ref>). The data were collected by 0.1 m<ref>2</ref> Hamon grab from 208 locations on a pre-planned survey grid. Exploratory analysis found no duplicate locations in this data set. This is a sizeable data set to support a spatial analysis, so as described for Swallow Sand in section 2.1 above, no attempt was made to supplement these data with others from the BGS archive.

	===Exploratory data analysis and transformation===		===Exploratory data analysis and transformation===

Dbk: /* Spatial analysis */

2015-08-06T09:18:37Z

Spatial analysis

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	==Spatial analysis==		==Spatial analysis==
	The same procedures used with the Swallow Sand data were used to compute estimates of the auto- and cross variograms, and to fit LMCRs to the data for SWDW, and these are shown in Figure 6.		The same procedures used with the Swallow Sand data were used to compute estimates of the auto- and cross variograms, and to fit LMCRs to the data for SWDW, and these are shown in Figure 6.
			{{clear}}
	[[Image:14015 fig6.jpg\|thumb\|left\|500px\|'''Figure 6''' Estimated variograms and cross-variograms with fitted linear model of coregionalizations for alr-mud and alr-sand for SWSW. Solid symbols are method of moment estimates with fitted model in red. Open symbols are mimimum volume ellipsoid estimates with fitted model in blue.]]		[[Image:14015 fig6.jpg\|thumb\|left\|500px\|'''Figure 6''' Estimated variograms and cross-variograms with fitted linear model of coregionalizations for alr-mud and alr-sand for SWSW. Solid symbols are method of moment estimates with fitted model in red. Open symbols are mimimum volume ellipsoid estimates with fitted model in blue.]]
			{{clear}}
	Cross-validation results for the two sets of auto-variograms are presented in Table 9.		Cross-validation results for the two sets of auto-variograms are presented in Table 9.

Dbk at 09:18, 6 August 2015

2015-08-06T09:18:24Z

← Older revision		Revision as of 10:18, 6 August 2015
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	{{OR/14/015}}		{{OR/14/015}}
	==Data==		==Data==
			The data used for the South-west Deeps (West) MCZ (SWDW) are particle size analyses from the verification survey carried out by Cefas in 2013 (McIlwaine, 2013<ref name="McIlwaine">MCILWAINE, P. 2013 South-West Deeps (West) recommended Marine Conservation Zone (rMCZ) Survey Report: C5785H. Issue date: 24 July 2013. </ref>). The data were collected by 0.1 m2 Hamon grab from 208 locations on a pre-planned survey grid. Exploratory analysis found no duplicate locations in this data set. This is a sizeable data set to support a spatial analysis, so as described for Swallow Sand in section 2.1 above, no attempt was made to supplement these data with others from the BGS archive.
	The data used for the South-west Deeps (West) MCZ (SWDW) are particle size analyses from the verification survey carried out by Cefas in 2013 (McIlwaine, 2013). The data were collected by 0.1 m2 Hamon grab from 208 locations on a pre-planned survey grid. Exploratory analysis found no duplicate locations in this data set. This is a sizeable data set to support a spatial analysis, so as described for Swallow Sand in section 2.1 above, no attempt was made to supplement these data with others from the BGS archive.

	===Exploratory data analysis and transformation===		===Exploratory data analysis and transformation===
	Exploratory statistics of the 208 particle size data are shown in Table 7 below. Eight zero values were recorded for gravel content and 2 for mud content. Non-zero values were imputed as for the Swallow Sand data, following Lark et al. (2012). Table 8 shows summary statistics of the alr-transformed data		Exploratory statistics of the 208 particle size data are shown in Table 7 below. Eight zero values were recorded for gravel content and 2 for mud content. Non-zero values were imputed as for the Swallow Sand data, following Lark et al. (2012)<ref name="Lark 2012">LARK, R M, DOVE, D, GREEN, S, RICHARDSON, A E, STEWART, H, and STEVENSON, A. 2012. Spatial prediction of seabed sediment texture classes by cokriging from a legacy database of point observations. ''Sedimentary Geology'', Vol. 281, 35–49. </ref>. Table 8 shows summary statistics of the alr-transformed data

	{\| class="wikitable"		{\| class="wikitable"
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	==Spatial analysis==		==Spatial analysis==

	The same procedures used with the Swallow Sand data were used to compute estimates of the auto- and cross variograms, and to fit LMCRs to the data for SWDW, and these are shown in Figure 6.		The same procedures used with the Swallow Sand data were used to compute estimates of the auto- and cross variograms, and to fit LMCRs to the data for SWDW, and these are shown in Figure 6.

	[[Image:14015 fig6.jpg\|thumb\|~~center~~\|500px\|'''Figure 6''' Estimated variograms and cross-variograms with fitted linear model of coregionalizations for alr-mud and alr-sand for SWSW. Solid symbols are method of moment estimates with fitted model in red. Open symbols are mimimum volume ellipsoid estimates with fitted model in blue.]]		[[Image:14015 fig6.jpg\|thumb\|left\|500px\|'''Figure 6''' Estimated variograms and cross-variograms with fitted linear model of coregionalizations for alr-mud and alr-sand for SWSW. Solid symbols are method of moment estimates with fitted model in red. Open symbols are mimimum volume ellipsoid estimates with fitted model in blue.]]

	Cross-validation results for the two sets of auto-variograms are presented in Table 9.		Cross-validation results for the two sets of auto-variograms are presented in Table 9.
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	{\| class="wikitable"		{\| class="wikitable"
	\|+ Table 10 Parameters of the linear model of coregionalization based on method-of- moments for SWDW.		\|+ Table 10 Parameters of the linear model of coregionalization based on method-of-moments for SWDW.

	\| Component		\| Component
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	Figure 7 below shows the conditional expectation of gravel, sand and mud across the SWDW MCZ, and Figure 8 shows the 0.025 and 0.975 quantile which define a 95% confidence interval for mud content.		Figure 7 below shows the conditional expectation of gravel, sand and mud across the SWDW MCZ, and Figure 8 shows the 0.025 and 0.975 quantile which define a 95% confidence interval for mud content.
			{{Clear}
			[[Image:14015 fig7.jpg\|thumb\|left\|500px\|'''Figure 7''' Conditional Expectation of gravel, sand and mud content (proportions) across the SWDW MCZ based on multiple realizations of the prediction distribution.]]

	[[Image:14015 fig7.jpg\|thumb\|center\|500px\|'''Figure 7''' Conditional Expectation of gravel, sand and mud content (proportions) across the SWDW MCZ based on multiple realizations of the prediction distribution.]]		[[Image:14015 fig8.jpg\|thumb\|left\|500px\|'''Figure 8''' Upper (top) and lower (bottom) bounds of the 95% confidence interval for mud content (proportion) across the SWDW MCZ based on multiple realizations of the prediction distribution .]]
			{{Clear}}
	[[Image:14015 fig8.jpg\|thumb\|~~center~~\|500px\|'''Figure 8''' Upper (top) and lower (bottom) bounds of the 95% confidence interval for mud content (proportion) across the SWDW MCZ based on multiple realizations of the prediction distribution .]]

	Figure 9 below shows the most probable EUNIS class across the Swallow Sand MCZ, and the probability of the most probable class. Figure 10 shows the probability of each class.		Figure 9 below shows the most probable EUNIS class across the Swallow Sand MCZ, and the probability of the most probable class. Figure 10 shows the probability of each class.
			{{clear}}
			[[Image:14015 fig9.jpg\|thumb\|left\|500px\|'''Figure 9''' Most probable EUNIS class (top) across the SWDW MCZ and probability of the most probable class (bottom).]]

	[[Image:14015 ~~fig9~~.jpg\|thumb\|~~center~~\|500px\|'''Figure 9''' ~~Most probable~~ EUNIS class (top) across the SWDW MCZ and probability of the ~~most probable class (bottom)~~.]]		[[Image:14015 fig10.jpg\|thumb\|left\|500px\|'''Figure 10''' Probability of finding each EUNIS class (top) across the SWDW MCZ.]]
			{{clear}}
			As at Swallow Sand, class Sand and Muddy Sand is delineated as most probable across most of the SWDW MCZ. Uncertainty is greatest in central eastern parts of the zone, including areas where classes Mixed and Coarse have largest probability. While there is significant nugget variance in the LMCR for SWDW, there is stronger spatial dependence than at Swallow Sand. The mapped conditional expectations show local patches where the gravel content of the sediment is larger than average, and a general reduction in sand content of the sediment from south-west to north-east.

	~~[[Image:14015 fig10.jpg\|thumb\|center\|500px\|'''Figure 10''' Probability of finding each EUNIS class (top) across the SWDW MCZ.]]~~		==References==

	As at Swallow Sand, class Sand and Muddy Sand is delineated as most probable across most of the SWDW MCZ. Uncertainty is greatest in central eastern parts of the zone, including areas where classes Mixed and Coarse have largest probability. While there is significant nugget variance in the LMCR for SWDW, there is stronger spatial dependence than at Swallow Sand. The mapped conditional expectations show local patches where the gravel content of the sediment is larger than average, and a general reduction in sand content of the sediment from south-west to north-east.

	[[Category:OR/14/015 Mapping seabed sediments of the Swallow Sand and South-west Deeps (West) MCZs \| 03]]		[[Category:OR/14/015 Mapping seabed sediments of the Swallow Sand and South-west Deeps (West) MCZs \| 03]]

Dbk: Protected "OR/14/015 South-west Deeps (West)" ([Edit=Allow only administrators] (indefinite) [Move=Allow only administrators] (indefinite)) [cascading]

2015-05-05T15:09:46Z

Protected "OR/14/015 South-west Deeps (West)" ([Edit=Allow only administrators] (indefinite) [Move=Allow only administrators] (indefinite)) [cascading]

← Older revision	Revision as of 16:09, 5 May 2015
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Dbk at 15:27, 14 April 2015

2015-04-14T15:27:25Z

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	Figure 7 below shows the conditional expectation of gravel, sand and mud across the SWDW MCZ, and Figure 8 shows the 0.025 and 0.975 quantile which define a 95% confidence interval for mud content.		Figure 7 below shows the conditional expectation of gravel, sand and mud across the SWDW MCZ, and Figure 8 shows the 0.025 and 0.975 quantile which define a 95% confidence interval for mud content.

	[[Image:14015 fig7.jpg\|thumb\|center\|500px\|Figure 7 Conditional Expectation of gravel, sand and mud content (proportions) across the SWDW MCZ based on multiple realizations of the prediction distribution.]]		[[Image:14015 fig7.jpg\|thumb\|center\|500px\|'''Figure 7''' Conditional Expectation of gravel, sand and mud content (proportions) across the SWDW MCZ based on multiple realizations of the prediction distribution.]]

			[[Image:14015 fig8.jpg\|thumb\|center\|500px\|'''Figure 8''' Upper (top) and lower (bottom) bounds of the 95% confidence interval for mud content (proportion) across the SWDW MCZ based on multiple realizations of the prediction distribution .]]

	[[Image:14015 fig8.jpg\|thumb\|center\|500px\|Figure 8 Upper (top) and lower (bottom) bounds of the 95% confidence interval for mud content (proportion) across the SWDW MCZ based on multiple realizations of the prediction distribution .]]
	Figure 9 below shows the most probable EUNIS class across the Swallow Sand MCZ, and the probability of the most probable class. Figure 10 shows the probability of each class.		Figure 9 below shows the most probable EUNIS class across the Swallow Sand MCZ, and the probability of the most probable class. Figure 10 shows the probability of each class.

	[[Image:14015 fig9.jpg\|thumb\|center\|500px\|Figure 9 Most probable EUNIS class (top) across the SWDW MCZ and probability of the most probable class (bottom).]]		[[Image:14015 fig9.jpg\|thumb\|center\|500px\|'''Figure 9''' Most probable EUNIS class (top) across the SWDW MCZ and probability of the most probable class (bottom).]]

	[[Image:14015 fig10.jpg\|thumb\|center\|500px\|Figure 10 Probability of finding each EUNIS class (top) across the SWDW MCZ.]]		[[Image:14015 fig10.jpg\|thumb\|center\|500px\|'''Figure 10''' Probability of finding each EUNIS class (top) across the SWDW MCZ.]]

	As at Swallow Sand, class Sand and Muddy Sand is delineated as most probable across most of the SWDW MCZ. Uncertainty is greatest in central eastern parts of the zone, including areas where classes Mixed and Coarse have largest probability. While there is significant nugget variance in the LMCR for SWDW, there is stronger spatial dependence than at Swallow Sand. The mapped conditional expectations show local patches where the gravel content of the sediment is larger than average, and a general reduction in sand content of the sediment from south-west to north-east.		As at Swallow Sand, class Sand and Muddy Sand is delineated as most probable across most of the SWDW MCZ. Uncertainty is greatest in central eastern parts of the zone, including areas where classes Mixed and Coarse have largest probability. While there is significant nugget variance in the LMCR for SWDW, there is stronger spatial dependence than at Swallow Sand. The mapped conditional expectations show local patches where the gravel content of the sediment is larger than average, and a general reduction in sand content of the sediment from south-west to north-east.

	[[Category:OR/14/015 Mapping seabed sediments of the Swallow Sand and South-west Deeps (West) MCZs \| 03]]		[[Category:OR/14/015 Mapping seabed sediments of the Swallow Sand and South-west Deeps (West) MCZs \| 03]]

Dbk at 15:21, 14 April 2015

2015-04-14T15:21:53Z

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	As at Swallow Sand, class Sand and Muddy Sand is delineated as most probable across most of the SWDW MCZ. Uncertainty is greatest in central eastern parts of the zone, including areas where classes Mixed and Coarse have largest probability. While there is significant nugget variance in the LMCR for SWDW, there is stronger spatial dependence than at Swallow Sand. The mapped conditional expectations show local patches where the gravel content of the sediment is larger than average, and a general reduction in sand content of the sediment from south-west to north-east.		As at Swallow Sand, class Sand and Muddy Sand is delineated as most probable across most of the SWDW MCZ. Uncertainty is greatest in central eastern parts of the zone, including areas where classes Mixed and Coarse have largest probability. While there is significant nugget variance in the LMCR for SWDW, there is stronger spatial dependence than at Swallow Sand. The mapped conditional expectations show local patches where the gravel content of the sediment is larger than average, and a general reduction in sand content of the sediment from south-west to north-east.

	[[Category:OR/14/015 Mapping seabed sediments of the Swallow Sand and South-west Deeps (West) MCZs \| 01]]		[[Category:OR/14/015 Mapping seabed sediments of the Swallow Sand and South-west Deeps (West) MCZs \| 03]]

Dbk: Created page with "notoc {{OR/14/015}} ==Data== The data used for the South-west Deeps (West) MCZ (SWDW) are particle size analyses from the verification survey carried out by Cefas in 2013..."

2015-04-14T14:06:55Z

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__notoc__
{{OR/14/015}}
==Data==

The data used for the South-west Deeps (West) MCZ (SWDW) are particle size analyses from the verification survey carried out by Cefas in 2013 (McIlwaine, 2013). The data were collected by 0.1 m2 Hamon grab from 208 locations on a pre-planned survey grid. Exploratory analysis found no duplicate locations in this data set. This is a sizeable data set to support a spatial analysis, so as described for Swallow Sand in section 2.1 above, no attempt was made to supplement these data with others from the BGS archive.

===Exploratory data analysis and transformation===
Exploratory statistics of the 208 particle size data are shown in Table 7 below. Eight zero values were recorded for gravel content and 2 for mud content. Non-zero values were imputed as for the Swallow Sand data, following Lark et al. (2012). Table 8 shows summary statistics of the alr-transformed data

{| class="wikitable"
|+ Table 7 Summary statistics of particle size data from SWDW.

|
| Gravel /%
| Mud /%
| Sand /%
|-
| Mean
| 3.86
| 8.59
| 87.55
|-
| Minimum
| 0.00
| 0.00
| 42.85
|-
| Maximum
| 30.80
| 30.18
| 98.71
|-
| Standard deviation
| 6.71
| 5.23
| 8.75
|}

{| class="wikitable"
|+ Table 8 Summary statistics of additive log-ratio transformed data from SWDW.
|
| alr-mud
| alr-sand
|-
| Mean
| 2.01
| 4.55
|-
| Minimum
| 1.87
| 4.51
|-
| Standard deviation
| 2.30

| 2.06
|-
| Skewness
| 0.035
| 0.448
|}

==Spatial analysis==

The same procedures used with the Swallow Sand data were used to compute estimates of the auto- and cross variograms, and to fit LMCRs to the data for SWDW, and these are shown in Figure 6.

[[Image:14015 fig6.jpg|thumb|center|500px|'''Figure 6''' Estimated variograms and cross-variograms with fitted linear model of coregionalizations for alr-mud and alr-sand for SWSW. Solid symbols are method of moment estimates with fitted model in red. Open symbols are mimimum volume ellipsoid estimates with fitted model in blue.]]

Cross-validation results for the two sets of auto-variograms are presented in Table 9.

{| class="wikitable"
|+ Table 9 Cross-validation results for SWDW.

|

| colspan="2" | Method of Moments

|
| me
|-
| '''Estimator Variable'''
| alr-mud
| alr-sand
| alr-mud
| alr-sand
|-
| Mean of ''θ ''('''x''')
| 1.17
| 1.02
| 1.85
| 1.51
|-
| Median of ''θ ''('''x''')
| 0.47
| 0.45
| 0.68
| 0.61
|}

As for the Swallow Sand data the cross-validation results for the auto-variograms based on MoM estimates give results very close to those expected for the correct model and so the LMCR based on the MoM estimates can be used in further work. Its parameters are given in Table 10 below.

{| class="wikitable"
|+ Table 10 Parameters of the linear model of coregionalization based on method-of- moments for SWDW.

| Component
| Spatial correlation model type
| colspan="2" | Distance parameter of spatial model/metres

| colspan="3" | Variance or Covariance Component
|-
|
|
|

| colspan="2" | Auto-variogram
| Cross-variogram
|-
|
|
|
| alr-mud
| alr-sand
|
|-
| 1
| Nugget
| N.A.
| 1.97
| 1.75
| 1.56
|-
| 2
| Spherical
| 6892
| 1.13
| 1.15
| 0.69
|-
| 3
| Spherical
| 28412
| 2.40
| 1.81
| 0.96
|}

==Spatial predictions==
Spatial predictions were carried out as described for the Swallow Sand MCZ in section 2.3. The output files are SWDW_predictions.dat with the conditional expectations of gravel, sand and mud content and associated measures of uncertainty (same structure as described in Table 5 for the comparable file from Swallow Sand) and SWDW_classes.dat, with the EUNIS class probabilities (same structure as described in Table 6 for the comparable file from Swallow Sand).

Figure 7 below shows the conditional expectation of gravel, sand and mud across the SWDW MCZ, and Figure 8 shows the 0.025 and 0.975 quantile which define a 95% confidence interval for mud content.

[[Image:14015 fig7.jpg|thumb|center|500px|Figure 7 Conditional Expectation of gravel, sand and mud content (proportions) across the SWDW MCZ based on multiple realizations of the prediction distribution.]]

[[Image:14015 fig8.jpg|thumb|center|500px|Figure 8 Upper (top) and lower (bottom) bounds of the 95% confidence interval for mud content (proportion) across the SWDW MCZ based on multiple realizations of the prediction distribution .]]
Figure 9 below shows the most probable EUNIS class across the Swallow Sand MCZ, and the probability of the most probable class. Figure 10 shows the probability of each class.

[[Image:14015 fig9.jpg|thumb|center|500px|Figure 9 Most probable EUNIS class (top) across the SWDW MCZ and probability of the most probable class (bottom).]]

[[Image:14015 fig10.jpg|thumb|center|500px|Figure 10 Probability of finding each EUNIS class (top) across the SWDW MCZ.]]

As at Swallow Sand, class Sand and Muddy Sand is delineated as most probable across most of the SWDW MCZ. Uncertainty is greatest in central eastern parts of the zone, including areas where classes Mixed and Coarse have largest probability. While there is significant nugget variance in the LMCR for SWDW, there is stronger spatial dependence than at Swallow Sand. The mapped conditional expectations show local patches where the gravel content of the sediment is larger than average, and a general reduction in sand content of the sediment from south-west to north-east.

[[Category:OR/14/015 Mapping seabed sediments of the Swallow Sand and South-west Deeps (West) MCZs | 01]]