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Page 1: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations 1

Page 2: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

Geophysical measurements comprises different non-destructive methods to measure various parameters of the soil or terrain. The meassurements can be carried out on the ground, in the air, on the water or in boreholes.

Ramboll has conducted geophysical measurements for more than 30 years on various projects regarding:

• Infrastructure • Environmental assessments • Mining • Oil and gas • Offshore constructions (wind farms, cables, harbours etc.)

Ramboll is today Scandinavia's largest geophysical consultant outside the offshore and oil/gas industry.

Ramboll use and master a variety of methods, which means that we have the best opportunities to advise on the best method to be used for the various purposes.

Geophysical services in Ramboll

Presenter
Presentation Notes
Content slide
Page 3: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

Geophysical services in Ramboll Ramboll offers the following services:

Geophysical borehole logging

Seismic surveys

• Reflection and Refraction Seismic • Shear and Surface Wave • Borehole seismic (VSP) • Crosshole Sonic Logging (CSL)

Electric and electromagnetic methods

Georadar, Metaldetector and Gravity

Magnetic Resonance Sounding (MRS)

Marine surveys

• Seismic surveys • Multibeam eccosounder • Bathymetry and Side scan sonar • Cable tracking

Malmö Citytunnel Holma TBM Starting wall

Malmö Citytunnel. Cored 146mm borehole. Broyzoan limestone

Presenter
Presentation Notes
Content slide
Page 4: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

Geophysical services in Ramboll Offshore Measurements

Electrical and electromagnetic methods

Georadar & Magnetic

Borehole logging & seismic

Seismic surveys

GPR 100MHz

Slingram 6m depth

SkyTEM

Landstreamer seismic

Seismic profiles in 3D

All examples in this presentation are from Ramboll projects

Logging truck Storstrommen Bridge 2014

Page 5: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

Mapping of overburden, delineation of ore deposits, structures and faults in bedrock.

Ramboll offers a comprehensive suite of seismic methods:

Land streamer vibroseis – pioneered by Ramboll. High resolution shallow reflection seismic primarily performed on all types of roads. As well as off-road - depending on conditions.

2D reflection P & S-wave surveys: High resolution surveys with up to 120 channels, utilizing different sources: minivib (10-500Hz), explosives, accelerated weight drop or hammer.

Refraction surveys: mapping of top of bedrock both land- and marine survey

Surface Waves surveys. Very shallow (0-50m), mapping of overburden, calculation of geotechnical dynamic parameters

Borehole seismics: VSP or cross-hole tomography, calculation of seismic velocities, Crosshole Sonic Logging

Marinstreamer – Multichannel seismic High resolution shallow offshore reflection seismic

Seismic Methods

ISUA Greenland

Page 6: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

Legend:Pulled Array Seismic line, shown to the leftPulled Array Seismic line

Reflection Seismic – Landstreamer vibroseis

Example of land steamer reflection seismic recorded on road. The profile is 5km long and app 1km high. The purpose with the survey was to find sand/gravel structures which can be potential groundwater reservoirs. Example from south Jutland in Denmark.

Sand/gravel groundwater reservoir

App. 1000m deep

The Hermitage Palace Dyrehaven north of Copenhagen

IVI Vibrator 3.5 t

Geophones

Page 7: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

Reflection Seismic - Carlsberg fault

Example of why it is a good idea to measure deeper than depth of construction. The fault (red lines) is 300m deep and can clearly be seen on the data. This would not had been seen if the investigation had only gone to the construction depth of 40-50m. Ørestad Copenhagen. Recorded in 4 hours with crew of only 2

Copenhagen

Page 8: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

The depth to limestone is interpreted to follow the 2500m/s line. Copenhagen centrum

Helsingborg Sweden. Interpreted faults and structures. All profiles (roads) shown in 3D plot 4km long 2km wide

Limestone depth

Sand – and shalestone

Tomographic Refraction analysis, first arrivel picking from landsstreamer seismic

Reflection Seismic – Refraction analysis Recorded on roads in Copenhagen and Helsingborg

Page 9: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

Onshore-------!-------Offshore (marine) -----------------

Refraction Seismic - Depth to bedrock

PEG-40 Hammer

Page 10: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

An example of combining two methods to obtain useful information of the sub surface. Both methods is recorded along the same profile. Refraction seismic in the top, resistivity measurements in the bottom (Geoelectrical profiling).

Refraction/Resistivity - Depth to bedrock

Page 11: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

Geological profiles after interpretation of the sand structures. The original boreholes was not deep enough to reach the depth of the sand reservoir. The investigations resulted in new deeper boreholes to verify the results from the seismic data.

The Shear wave velocity soundings used for geotechnical calculations overlaying a Shear (S) wave reflection profile. The example is from the port to the Storebælts tunnel in Denmark.

Surface Waves – MASW and S-wave Reflection Formation parameters

Page 12: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

Borehole Seismic – VSP - Formation parameters

Borehole Seismic - Vertical Seismic Profiling (VSP) The dynamic parameters of the formation: G – Module, Young and Poisson ratio; can be calculated using the measured density and Shear (S-wave) and P-wave velocity of the formation. For landstreamer seismic the VSP measurement is typical done using a Hydrophone cable with 20 hydrophones which is lowered into the borehole. The source is typical the seismic vibrator

VSP fieldwork on Bermuda

Page 13: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

Crosshole Sonic Logging (CSL)

Borehole Seismic – Crosshole Sonic Logging (CSL) Variations in the concrete in deep foundation piles and concrete walls can be determined by using a crosshole sonic logging system (CSL). Prompted by industry demand for a method to test the structural integrity of concrete in foundation piles Ramboll has invested in the SCXT3000 crosshole sonic logging system.

Based on the collected data Rambøll performs a thorough interpretation of each pile. This is gathered in a complete report where all interpretations are highlighted in text in addition to the interpreted individual profiles.

Page 14: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

Geophysical Borehole Logging

Kiruna

Optical televiewer Borehole wall 360 degree Forsmark SKB

Virtual core (3D caliper) from acoustical televiewer with results from optical televiewer folded around

25,3

25,4

25,5

Page 15: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

Geophysical Borehole Logging - Logs

Ramboll services includes: Geological interpretation, Hydrogeology, Physical properties, Elastic parameters, Fissure zones, Logstratigraphy, Optical televiewer – virtual core, Acustic televiewer, Deviation measurements

A great advantage of borehole logging compared to core measurements, it gives a more complete continuous series of undisturbed measurements, no missing sections! Additionally it is much faster and cheaper!

Example from shale gas exploration

Page 16: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

-5

Zone 1

Clay till

LevelMetre

Zone 2

0

-10

-15

-20

-25

-30

-6

-6

0 10 30k for Zone 2h

4020 50 10 m/s

2000 10 m/s

Example from Malmö harbour and Malmö Cititunnel

Geophysical Borehole Logging - Flowlogs

On the background of app. 15 flowlogs, it could be documented that there would be a significant reduction in water-inflow, if the upper most part of the formation were grouted.

<- The black curve is showing the water inflow, before cementing the uppermost part of the borehole. The red/blue curve is the results after the cementing.

Page 17: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

Geophysical Borehole Logging - Televiewers

Example of fracture analysis, comparing the core with results form logging with acoustical- and optical televiewer logs. Cityringen in Copenhagen

Acoustical Optical Core Fracture dip/azimuth Induration Fissures

Page 18: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

Geophysics – surface and airborne methods Resistivity - ERT/PACES/DualEM: Mapping of overburden and/or shallow targets in the bedrock

Electromagnetic - TEM: Mapping of low resistive zones and mineralisations

Airborne method - SkyTEM: Regional mapping

Ground penetration radar - GPR Mapping of top of bedrock and shallow targets in the bedrock

Gravimetric/Magnetometer: Regional mapping of structural features, high density ores or magnetic material

Page 19: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

Resistivity - Electromagnetic profiling – Slingram

Simple method for finding peat and other soft layer in a area down to app. 5m

Method for mapping of geological structures down to depth between 25 - 120m (depending of the field setup).

Resistivity - Geoelectrical profiling – CVES/ERT/IP

Page 20: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

Near surface resistivity mapping of a large area. Recording speed 10km/h, survey depth app. 6m.

The Resistivity is recorded to 6 depths: 0.5m, 1m, 1.5m, 2m, 3m and 6m.

Interpretation profile with borehole.

Resistivity - Electromagnetic profiling – DualEM

Page 21: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

0 m – 5 m

5 m – 10 m

10 m – 15 m

15 m – 20 m

20 m – 25 m

25 m – 30 m

Near surface resistivity mapping of a large area. App. 15km profile lines pr. day, survey depth 25m.

Resistivity - Geoelectrical profiling – PACES

Page 22: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

Resistivity - WalkTEM – TDEM Sounding

High shallow resolution combined with very deep penetration

Page 23: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

Receiver

Transmitter loop

Resistivity mapping of a large area and along infrastructure (pipeline, roads). Survey speed up to 150km/h. Survey depth up to more than 500m.

Result, map showing variations in resistivity, used to interpret the presence of water aquifers (high resistivity - red color)

Resistivity – Helicopter EM - SkyTEM

Page 24: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

Multiple possibilities for utilization

Road survey speed 70km/h Concrete tunnel Interpretated asphalt thickness

Rail survey speed 70km/h

Center channel. 21 channels spaced with 7.5cm

Surface map all channels, e.g. 0.3 m depth

Center channel

Cross section

3D Ground Penetration Radar

Page 25: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

Screening for possibilities for utilization and archaeological remains 3D Ground Penetration Radar

Setup with ATV for larger areas

Setup on cart for small areas and indoor. Vojens heating

Remains from ring fortress - Denmark

Page 26: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

• The depth to the bedrock on Bog “Myr”

• 50 MHz and 100 MHz antenna with a estimated penetration up to 20 m

• Results: Depth Map GPR profile with interpretations

Andmyran Norway

Ground Penetration Radar - Depth to bedrock

Page 27: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

Mapping the thickness of the Inland ice in Greenland using:

• Georadar 40, 80 and 200 MHz with a estimated penetration of up to 400 m

• Reflection seismic

Bedrock

Moraine

Bedrock

Lot of Ice

GPR

Seismic 400m Deep

Mount Isua Greenland

GPR and reflection seismic - Depth to bedrock

2 km Long

Page 28: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

Gravimetric survey

Scintrex CG-3M (left)

Ground Magnetic survey

Total magnetic field grid

Gravity data. Bouguer amomaly

Potassium GEM GSMP35, Caesium Geometrics G859A Proton GEM GSM-19TW

Page 29: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

Elektromagnetic Metaldetector – EM61 Mapping of unexploded ordnance (UXO) or metal constructions in the ground e.g. oil tank

The metal detector is used for control of the cleaning of old military fields, e.g. for placing of boreholes in the area. Another use is finding oil tanks on petrol stations and buried metal objects in fields

Landfield area. Border recorded (red metal/green no metal)

Old Military shooting field. Spikes are potential buried UXO

Page 30: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

MRS – Magnetic Resonance Sounding

Laser scanning stationary, mobil on land and sea

Gravity data. Bouguer amomaly

Laser --- waterlevel Multibeam

Method to find groundwater aquifer before drilling

BING Map

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Geophysical investigations 31

Ramboll has specialised in providing high quality marine geophysical investigations. Our services comprises acquisition, processing and experienced interpretation of Multibeam, Backscatter, Side Scan Sonar, Magnetometer, Single and Multichannel seismic.

Harbour entrance

Dredging disposal site

Bathymetry

Side scan sonar

Sand ripples to fine sediment

Single- and Multi-channel seismic

Multichannel seicmic section, Sparker source, depth app. 300m

Bathymetric (top) and Side Scan Sonar (bottom) Dataset of identified wreck

Marine Geophysical Investigations

Page 32: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

Survey lines & Magnetic Objects Depth to seabed (Bathymetry) Multibeam Echo Sounder

Seabed Classification & objects Magnetometer Side Scan Sonar - image of the seabed

Bridge trace

Geological model - Depth limestone Refraction- and Multichannel seismic

New Storstrømmen Bridge 2014

Survey vessel Easy mobilisation

Marine Geophysic Surveys - Sub- and Seabed

Presenter
Presentation Notes
Content slide, two columns with 2 images. Image size: 3,99 cm x 10,76 cm or 151 x 407 pixels
Page 33: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

Geophysical investigations

This survey provides confirmation of the position of existing cables buried in the seabed or beach and information of the seabed conditions using Electromagnetic geophysical instruments, Multibeam and Side Scan Sonar all mounted on ROV

Cable – not buried

Cable and pipe tracking – Offshore and onshore

ROV Crawler

Orion Cable and Pipeline tracker

Cable trench

Orion Cable and Pipeline tracker

3D Georadar

Page 34: Geophysical investigations - Ramboll Environdownload.ramboll-environ.com/ramboll/geophysics/17...Geophysical investigations Geophysical measurements comprises different nondestructive

GOING GLOBAL ENVIRON JOINS RAMBOLL

Rune Jørgensen Chief Project Manager Ramboll Denmark Phone +45 5161 6659 E-mail: [email protected]

Uffe T. Nielsen Project Director Ramboll Denmark Phone +45 5161 6782 E-mail: [email protected]

Further information:

Roger Wisén Technical Manager Ramboll Denmark Phone +45 5161 6779 E-mail: [email protected]

Kristoffer Vrang Head of Department Ramboll Denmark Phone +45 5161 6767 E-mail: [email protected]

Presenter
Presentation Notes
Endslide