Detailed visual seabed survey at drilling site 7218/11-1
Detailed visual seabed survey at drilling site 7218/11-1
Detailed visual seabed survey at drilling site 7218/11-1
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1 Introduction<br />
1.1 Background<br />
RepsolExplor<strong>at</strong>ionNorway AS(RENAS)is planningthe Darwin explor<strong>at</strong>ion well, <strong>7218</strong>/<strong>11</strong>-1, (ED50<br />
UTM34N 8.001.215,E4<strong>11</strong>.870)in PL531.Thewell is loc<strong>at</strong>edapproxim<strong>at</strong>ely133nauticalmiles(246<br />
km) North Westof Hammerfestand177nauticalmiles(327km)North Westof Banakairport.<br />
Drilling<strong>at</strong> the well is plannedto be carriedout in in December2012.Duringthe planning, a needfor<br />
a detailed baseline<strong>survey</strong> to map spongedensitiesin the vicinity of the well loc<strong>at</strong>ion has been<br />
identified. Thepurposeof the Surveywasto identify potentialareasnearthe <strong>drilling</strong>loc<strong>at</strong>ionsuitable<br />
for depositingdrill cuttings..<br />
Figure1.Explor<strong>at</strong>ionWell<strong>7218</strong>/<strong>11</strong>-1 (Darwin) loc<strong>at</strong>ionin the BarentsSea(source:RENAS)<br />
Thew<strong>at</strong>er depth <strong>at</strong> the loc<strong>at</strong>ion is approxim<strong>at</strong>ely320 metres., and the w<strong>at</strong>er movementalongthe<br />
<strong>seabed</strong>during the previous <strong>survey</strong> periods and assessmentscarried out in 20<strong>11</strong> and 2012 (DNV<br />
20<strong>11</strong>a; 20<strong>11</strong>b,2012) indic<strong>at</strong>eda strongnorth-eastwarddirection.<br />
1.2 Summary of previous <strong>survey</strong> s <strong>at</strong> Darwin<br />
1.2.1 Baseline <strong>survey</strong> 20<strong>11</strong><br />
Duringthe baseline<strong>survey</strong><strong>at</strong> Darwin in 20<strong>11</strong>(DNV20<strong>11</strong>)areaswith high density areasof sponges<br />
wereidentified(text insertedfrom DNV20<strong>11</strong>a/b):<br />
“Darwin is regardedas a speciesrich habit<strong>at</strong> with 49 taxa of benthic mega fauna recorded. The<br />
<strong>seabed</strong><strong>at</strong> Darwinhadhighdensitiesof soft bottom sponges.Spongecoverin c<strong>at</strong>egory“high density”<br />
constituted<strong>11</strong>.8%of the benthichabit<strong>at</strong>. ThismakesDarwinthe most spongerich field in the 20<strong>11</strong><br />
<strong>survey</strong>.Figure2 (note: Figure5-14 in original report) showsthe distribution of sponges<strong>at</strong> Darwin.<br />
Therewere no recordingsof coralsor red-listed speciesduringthe <strong>visual</strong>monitoring.Squ<strong>at</strong>lobsters<br />
were the most abundantmobile macro fauna and occurredin high numbersbetween spongesand<br />
pebbles.Rel<strong>at</strong>ivelyfew echinodermspecieswereobservedcomparedto other fields."<br />
<strong>Detailed</strong> <strong>site</strong> <strong>survey</strong> <strong>at</strong> PL531 Darwin<br />
Akvaplan-niva AS Rapport 6051 - 1 5