HESSELØ OWF
TECHNICAL DIALOGUE SOFT SEDIMENTS
Status on Site Investigations
AREA OF INTEREST
OWF Area:
• 247 km 2
• 30 km North of Zealand
• OWF Geophysical Survey – Fugro
• OWF Geotechnical Investigations – Gardline
• Integrated Geomodel – COWI (in progress – 02.2022) Cable Route Corridor
• 1000-1400 m wide and total length of 70 km
• Cable Route Survey – Rambøll
OWF
OWF – GEOPHYSICAL SURVEY OVERVIEW
Acquired data:
• MBES – Multibeam Echosounder
• SSS – Side Scan Sonar
• MAG – Magnetometer
• GS – Grab Samples
• SEIS – Seismic 2D
• 3D UHRS – 3D Ultra High Resolutions Seismic (at 2 OSS positions)
Deliverables:
• Reports (ens.dk/hesselo)
• Digital deliverables (Energinet ftp
server – see ens.dk/hesselo)
OWF – GEOTECHNICAL SITE INVESTIGATIONS OVERVIEW
Acquired data:
• 14 long boreholes & (3 short)
• 33 CPT
• 7 SCPT
• 5 PS-logging
• Investigations to 70 m below seafloor (BSF)
Deliverables:
• Draft Factual Report (ens.dk/hesselo)
• AGS data file (Energinet ftp server –
see ens.dk/hesselo)
CABLE ROUTE SURVEY OVERVIEW
Acquired data:
• MBES – Multibeam Echosounder
• SSS – Side Scan Sonar
• MAG – Magnetometer
• GS – Grab Samples
• SBP – Sub-bottom Profiler
• VC – Vibrocores
• CPT – Cone Penetration Test
• VC and CPT inside OWF
Deliverables:
• Reports (ens.dk/hesselo)
• Digital deliverables (Energinet ftp
server – see ens.dk/hesselo)
GEOLOGICAL SETTING – GEUS DESK STUDY
Pre-Quatenary depression / Deglaciation / very flat seabed 25-35m water depth
GEOPHYSICAL RESULTS
UNIT Expected soil type Age Depositional Environment Thickness Unit Base BSF
A CLAY to clayey medium SAND or sandy GYTTJA with
shells and shell fragments and organic material Holocene Marine 1-3 m 1-3 m
B Interlaminated to interbedded CLAY and SILT with
shells and shell fragments Early Holocene Deltaic 0-14 m 1-17 m
C Medium SAND with abundant shells and shell
fragments Early Holocene Shallow marine (Spit or Barrier Island) 0-3 m 0-17 m D CLAY with occasional laminae of SILT and/or SAND,
locally sandy Weichselian Glaciomarine, glaciolacustrine to fluvial 0-66 m 1-72 m E CLAY, locally with sand beds Weichselian Glaciomarine and/or glacial deposits 0-66 m 9-122 m F CLAY with laminae or thin beds of SILT or SAND Pleistocene Glaciomarine 0-39 m 14-113 m G Poorly sorted gravelly and sandy CLAY, SAND TILL or
CLAY TILL Pleistocene Glaciomarine and/or glacial till 0-94 m 27-166 m
H SAND, CLAY, CLAY TILL and/or SAND TILL Pleistocene Glacial, periglacial and/or glaciomarine 0-80 m 40-111 m I Sandy MUDSTONE, LIMESTONE and glauconitic
SANDSTONE Jurassic to Cretaceous Marine - -
Seismic mapping down to >100m, interpreted 9 Seismostratigraphic units
GEOPHYSICAL RESULTS
UNIT Expected soil type Age Depositional Environment Thickness Unit Base BSF
A CLAY to clayey medium SAND or sandy GYTTJA with shells and shell fragments and organic
material
Holocene Marine 1-3 m 1-3 m
B Interlaminated to interbedded CLAY and SILT with shells and shell fragments Early Holocene Deltaic 0-14 m 1-17 m C Medium SAND with abundant shells and shell
fragments Early Holocene Shallow marine (Spit or Barrier Island) 0-3 m 0-17 m D CLAY with occasional laminae of SILT and/or SAND, locally sandy Weichselian Glaciomarine, glaciolacustrine to
fluvial 0-66 m 1-72 m
E CLAY, locally with sand beds Weichselian Glaciomarine and/or glacial deposits 0-66 m 9-122 m F CLAY with laminae or thin beds of SILT or SAND Pleistocene Glaciomarine 0-39 m 14-113 m G Poorly sorted gravelly and sandy CLAY, SAND TILL
or CLAY TILL Pleistocene Glaciomarine and/or glacial till 0-94 m 27-166 m H SAND, CLAY, CLAY TILL and/or SAND TILL Pleistocene Glacial, periglacial and/or
glaciomarine 0-80 m 40-111 m
I Sandy MUDSTONE, LIMESTONE and glauconitic
SANDSTONE Jurassic to
Cretaceous Marine - -
UNIT A
GEOPHYSICAL RESULTS
UNIT Expected soil type Age Depositional Environment Thickness Unit Base BSF
A CLAY to clayey medium SAND or sandy GYTTJA with shells and shell fragments and organic
material
Holocene Marine 1-3 m 1-3 m
B Interlaminated to interbedded CLAY and SILT with shells and shell fragments Early Holocene Deltaic 0-14 m 1-17 m C Medium SAND with abundant shells and shell
fragments Early Holocene Shallow marine (Spit or Barrier Island) 0-3 m 0-17 m D CLAY with occasional laminae of SILT and/or SAND, locally sandy Weichselian Glaciomarine, glaciolacustrine to
fluvial 0-66 m 1-72 m
E CLAY, locally with sand beds Weichselian Glaciomarine and/or glacial deposits 0-66 m 9-122 m F CLAY with laminae or thin beds of SILT or SAND Pleistocene Glaciomarine 0-39 m 14-113 m G Poorly sorted gravelly and sandy CLAY, SAND TILL
or CLAY TILL Pleistocene Glaciomarine and/or glacial till 0-94 m 27-166 m H SAND, CLAY, CLAY TILL and/or SAND TILL Pleistocene Glacial, periglacial and/or
glaciomarine 0-80 m 40-111 m
I Sandy MUDSTONE, LIMESTONE and glauconitic
SANDSTONE Jurassic to
Cretaceous Marine - -
UNIT B
GEOPHYSICAL RESULTS
UNIT Expected soil type Age Depositional Environment Thickness Unit Base BSF
A CLAY to clayey medium SAND or sandy GYTTJA with shells and shell fragments and organic
material
Holocene Marine 1-3 m 1-3 m
B Interlaminated to interbedded CLAY and SILT with shells and shell fragments Early Holocene Deltaic 0-14 m 1-17 m C Medium SAND with abundant shells and shell
fragments Early Holocene Shallow marine (Spit or Barrier Island) 0-3 m 0-17 m D CLAY with occasional laminae of SILT and/or SAND, locally sandy Weichselian Glaciomarine, glaciolacustrine to
fluvial 0-66 m 1-72 m
E CLAY, locally with sand beds Weichselian Glaciomarine and/or glacial deposits 0-66 m 9-122 m F CLAY with laminae or thin beds of SILT or SAND Pleistocene Glaciomarine 0-39 m 14-113 m G Poorly sorted gravelly and sandy CLAY, SAND TILL
or CLAY TILL Pleistocene Glaciomarine and/or glacial till 0-94 m 27-166 m H SAND, CLAY, CLAY TILL and/or SAND TILL Pleistocene Glacial, periglacial and/or
glaciomarine 0-80 m 40-111 m
I Sandy MUDSTONE, LIMESTONE and glauconitic
SANDSTONE Jurassic to
Cretaceous Marine - -
UNIT C
GEOPHYSICAL RESULTS
UNIT Expected soil type Age Depositional Environment Thickness Unit Base BSF
A CLAY to clayey medium SAND or sandy GYTTJA with shells and shell fragments and organic
material
Holocene Marine 1-3 m 1-3 m
B Interlaminated to interbedded CLAY and SILT with shells and shell fragments Early Holocene Deltaic 0-14 m 1-17 m C Medium SAND with abundant shells and shell
fragments Early Holocene Shallow marine (Spit or Barrier Island) 0-3 m 0-17 m D CLAY with occasional laminae of SILT and/or SAND, locally sandy Weichselian Glaciomarine, glaciolacustrine to
fluvial 0-66 m 1-72 m
E CLAY, locally with sand beds Weichselian Glaciomarine and/or glacial deposits 0-66 m 9-122 m F CLAY with laminae or thin beds of SILT or SAND Pleistocene Glaciomarine 0-39 m 14-113 m G Poorly sorted gravelly and sandy CLAY, SAND TILL
or CLAY TILL Pleistocene Glaciomarine and/or glacial till 0-94 m 27-166 m H SAND, CLAY, CLAY TILL and/or SAND TILL Pleistocene Glacial, periglacial and/or
glaciomarine 0-80 m 40-111 m
I Sandy MUDSTONE, LIMESTONE and glauconitic
SANDSTONE Jurassic to
Cretaceous Marine - -
UNIT D
GEOPHYSICAL RESULTS
UNIT Expected soil type Age Depositional Environment Thickness Unit Base BSF
A CLAY to clayey medium SAND or sandy GYTTJA with shells and shell fragments and organic
material
Holocene Marine 1-3 m 1-3 m
B Interlaminated to interbedded CLAY and SILT with shells and shell fragments Early Holocene Deltaic 0-14 m 1-17 m C Medium SAND with abundant shells and shell
fragments Early Holocene Shallow marine (Spit or Barrier Island) 0-3 m 0-17 m D CLAY with occasional laminae of SILT and/or SAND, locally sandy Weichselian Glaciomarine, glaciolacustrine to
fluvial 0-66 m 1-72 m
E CLAY, locally with sand beds Weichselian Glaciomarine and/or glacial deposits 0-66 m 9-122 m F CLAY with laminae or thin beds of SILT or SAND Pleistocene Glaciomarine 0-39 m 14-113 m G Poorly sorted gravelly and sandy CLAY, SAND TILL
or CLAY TILL Pleistocene Glaciomarine and/or glacial till 0-94 m 27-166 m H SAND, CLAY, CLAY TILL and/or SAND TILL Pleistocene Glacial, periglacial and/or
glaciomarine 0-80 m 40-111 m
I Sandy MUDSTONE, LIMESTONE and glauconitic
SANDSTONE Jurassic to
Cretaceous Marine - -
UNIT E
GEOPHYSICAL RESULTS
UNIT Expected soil type Age Depositional Environment Thickness Unit Base BSF
A CLAY to clayey medium SAND or sandy GYTTJA with shells and shell fragments and organic
material
Holocene Marine 1-3 m 1-3 m
B Interlaminated to interbedded CLAY and SILT with shells and shell fragments Early Holocene Deltaic 0-14 m 1-17 m C Medium SAND with abundant shells and shell
fragments Early Holocene Shallow marine (Spit or Barrier Island) 0-3 m 0-17 m D CLAY with occasional laminae of SILT and/or SAND, locally sandy Weichselian Glaciomarine, glaciolacustrine to
fluvial 0-66 m 1-72 m
E CLAY, locally with sand beds Weichselian Glaciomarine and/or glacial deposits 0-66 m 9-122 m F CLAY with laminae or thin beds of SILT or SAND Pleistocene Glaciomarine 0-39 m 14-113 m G Poorly sorted gravelly and sandy CLAY, SAND TILL
or CLAY TILL Pleistocene Glaciomarine and/or glacial till 0-94 m 27-166 m H SAND, CLAY, CLAY TILL and/or SAND TILL Pleistocene Glacial, periglacial and/or
glaciomarine 0-80 m 40-111 m
I Sandy MUDSTONE, LIMESTONE and glauconitic
SANDSTONE Jurassic to
Cretaceous Marine - -
UNIT F
GEOPHYSICAL RESULTS
UNIT Expected soil type Age Depositional Environment Thickness Unit Base BSF
A CLAY to clayey medium SAND or sandy GYTTJA with shells and shell fragments and organic
material
Holocene Marine 1-3 m 1-3 m
B Interlaminated to interbedded CLAY and SILT with shells and shell fragments Early Holocene Deltaic 0-14 m 1-17 m C Medium SAND with abundant shells and shell
fragments Early Holocene Shallow marine (Spit or Barrier Island) 0-3 m 0-17 m D CLAY with occasional laminae of SILT and/or SAND, locally sandy Weichselian Glaciomarine, glaciolacustrine to
fluvial 0-66 m 1-72 m
E CLAY, locally with sand beds Weichselian Glaciomarine and/or glacial deposits 0-66 m 9-122 m F CLAY with laminae or thin beds of SILT or SAND Pleistocene Glaciomarine 0-39 m 14-113 m G Poorly sorted gravelly and sandy CLAY, SAND TILL
or CLAY TILL Pleistocene Glaciomarine and/or glacial till 0-94 m 27-166 m H SAND, CLAY, CLAY TILL and/or SAND TILL Pleistocene Glacial, periglacial and/or
glaciomarine 0-80 m 40-111 m
I Sandy MUDSTONE, LIMESTONE and glauconitic
SANDSTONE Jurassic to
Cretaceous Marine - -
UNIT G
GEOPHYSICAL RESULTS
UNIT Expected soil type Age Depositional Environment Thickness Unit Base BSF
A CLAY to clayey medium SAND or sandy GYTTJA with shells and shell fragments and organic
material
Holocene Marine 1-3 m 1-3 m
B Interlaminated to interbedded CLAY and SILT with shells and shell fragments Early Holocene Deltaic 0-14 m 1-17 m C Medium SAND with abundant shells and shell
fragments Early Holocene Shallow marine (Spit or Barrier Island) 0-3 m 0-17 m D CLAY with occasional laminae of SILT and/or SAND, locally sandy Weichselian Glaciomarine, glaciolacustrine to
fluvial 0-66 m 1-72 m
E CLAY, locally with sand beds Weichselian Glaciomarine and/or glacial deposits 0-66 m 9-122 m F CLAY with laminae or thin beds of SILT or SAND Pleistocene Glaciomarine 0-39 m 14-113 m G Poorly sorted gravelly and sandy CLAY, SAND TILL
or CLAY TILL Pleistocene Glaciomarine and/or glacial till 0-94 m 27-166 m H SAND, CLAY, CLAY TILL and/or SAND TILL Pleistocene Glacial, periglacial and/or
glaciomarine 0-80 m 40-111 m
I Sandy MUDSTONE, LIMESTONE and glauconitic
SANDSTONE Jurassic to
Cretaceous Marine - -
UNIT H
GEOPHYSICAL RESULTS
UNIT Expected soil type Age Depositional Environment Thickness Unit Base BSF
A CLAY to clayey medium SAND or sandy GYTTJA with shells and shell fragments and organic
material
Holocene Marine 1-3 m 1-3 m
B Interlaminated to interbedded CLAY and SILT with shells and shell fragments Early Holocene Deltaic 0-14 m 1-17 m C Medium SAND with abundant shells and shell
fragments Early Holocene Shallow marine (Spit or Barrier Island) 0-3 m 0-17 m D CLAY with occasional laminae of SILT and/or SAND, locally sandy Weichselian Glaciomarine, glaciolacustrine to
fluvial 0-66 m 1-72 m
E CLAY, locally with sand beds Weichselian Glaciomarine and/or glacial deposits 0-66 m 9-122 m F CLAY with laminae or thin beds of SILT or SAND Pleistocene Glaciomarine 0-39 m 14-113 m G Poorly sorted gravelly and sandy CLAY, SAND TILL
or CLAY TILL Pleistocene Glaciomarine and/or glacial till 0-94 m 27-166 m H SAND, CLAY, CLAY TILL and/or SAND TILL Pleistocene Glacial, periglacial and/or
glaciomarine 0-80 m 40-111 m
I Sandy MUDSTONE, LIMESTONE and glauconitic
SANDSTONE Jurassic to
Cretaceous Marine - -
UNIT I – Depth to top of Unit I (Bedrock)
GEOTECHNICAL RESULTS
CPT – Cone Penetration Test
• CPT profiles
CB – Combined Borehole (Borehole and CPT)
• Geological description
• Classification test
• Advanced lab test
OSS 1 – BOREHOLE LOG
CPT – Cone Resistance (qt) <3 MPa to 46m Seimostratigraphic units
UNIT Thickness Cumm. Thickness to base
A 1.8m
B 0.2m 2.1m
C -
D 29.6m 31.7m
E 18.1m 49.8m
F -
G -
H 19.8m 69.6m
OSS 2 – BOREHOLE LOG
CPT – Cone Resistance (qt) <3 Mpa to 14m Seimostratigraphic units
UNIT Thickness Cumm. Thickness to base
A 1.4m 1.4m
B 0.8m 2.2m
C 0.6m 2.7m
D 6.5m 9.3m
E 21.5m 30.7m
F - -
G - -
H 32.2m 62.9m
GEOTECHNICAL RESULTS
Aggregated CPT Cone Tip Resistance
92.5% of all measurements <10 MPa
Post glacial and Holocene sand layers
included
GEOTECHNICAL RESULTS
Undrained shear strength
• Blue: 138 UU Triaxial tests in Post glacial and Holocene core samples
• Orange 34 UU Triaxial tests in other
clay sediments
INTEGRATED GEOMODEL
• No Geotechnical data from Unit G
• Subdivision of Unit D, D1 to D4
COWI is performing this, but the figures and interpretation result are preliminary
UNIT Expected soil type Age Depositional Environment Thickness Unit Base BSF
A CLAY to clayey medium SAND or sandy GYTTJA with
shells and shell fragments and organic material Holocene Marine 1-3 m 1-3 m
B Interlaminated to interbedded CLAY and SILT with
shells and shell fragments Early Holocene Deltaic 0-14 m 1-17 m
C Medium SAND with abundant shells and shell
fragments Early Holocene Shallow marine (Spit or Barrier Island) 0-3 m 0-17 m D CLAY with occasional laminae of SILT and/or SAND,
locally sandy Weichselian Glaciomarine, glaciolacustrine to fluvial 0-66 m 1-72 m E CLAY, locally with sand beds Weichselian Glaciomarine and/or glacial deposits 0-66 m 9-122 m
F CLAY with laminae or thin beds of SILT or SAND Pleistocene Glaciomarine 0-39 m 14-113 m
G Poorly sorted gravelly and sandy CLAY, SAND TILL or
CLAY TILL Pleistocene Glaciomarine and/or glacial till 0-94 m 27-166 m
H SAND, CLAY, CLAY TILL and/or SAND TILL Pleistocene Glacial, periglacial and/or glaciomarine 0-80 m 40-111 m I Sandy MUDSTONE, LIMESTONE and glauconitic
SANDSTONE Jurassic to Cretaceous Marine - -
