Geophysical Testing

Geophysical Testing

Stuart Wells Ltd. have an extensive array of probes, resources and knowledge that can facilitate extensive borehole geophysical logging services centring around water wells and groundwater exploration in the UK.

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Borehole CCTV

• Borehole CCTV surveys are particularly useful when looking to inspect the condition of installed wells.
• These can be used to quickly identify issues associated with the well screen, borehole pump or riser to ultimately determine why a well maybe experiencing issues.
• These are also often used when drilling open hole to determine any major fractures and fissures and aid in the design aspect of the well. Borehole CCTV is a quick and easy logging technique.

We can offer the following probe specifications;

Probe	Axial Colour Camera	Dual View Colour Camera
Image Sensor	1/3" CCD	1/4" CCS
Resolution	550 TV Lines	620 TV Lines
Minimum Illumination	0.01 Lux	0.02 Lux
Lens Size	2.6mm	2.5mm and 2.9mm
External Diameter	42cm	62cm
Length	66cm	104cm

Borehole Verticality Logging

Borehole verticality surveys are an essential tool for anyone drilling a well. In any construction project knowing precisely where a well has been drilled and its direct path can save money and time as any project progresses.
For dewatering and well drilling, the inclination and deviation of a well can be essential when determining well installations as often deviation can mean that target aquifers are missed and borehole pumps can be difficult to install – ultimately saving clients’ money and time.
Our verticality testing is installed with a gyro device which prevents it being affected by steel sections and magnetic anomalies downhole.

We can offer the following probe specifications;

	Vertical Sonde
Length	60cm
Inclination Accurancy	+/- 0.4º
Azimuth Accuracy	+/- 1.0º
Range	0 - 360º

Borehole Caliper Logging

Borehole Caliper surveys are best used for plotting fractures and fissures within a drilled bore. When drilling in difficult ground conditions they are a perfect resource for identifying washout, faults and voiding.
They are also often used when undertaking quality checks, to ensure that a well screen has been installed correctly and there are no breaches to the wells integrity.
They are a perfect tool for quality assessment and for ensuring that vital fractures and fissures are not cut off when installing a well.

We can offer the following probe specifications;

Probe	3 Arm Caliper	4 Arm Caliper
Length	1.45m	1.18m
Diametre	38	80
Accuracy	+/- 3mm	+/- 3mm
Range	45 – 600mm	85 – 1000mm

OPTV (Optical Televiewer)

An optical televiewer is the prefect resource when drilling and installing any water well. The optical televiewer produces a high quality resolution video image of the borehole whilst also recording, azimuth dip and verticality, allowing for a perfect image and plot of the bore.
When undertaking packer testing, pumping tests and site investigation surveys these optical televiewer logs can provide essential information into determining testing zones, installing well liners, determining liner slot sizes, well materials and identifying major fractures and fissures.
These surveys have proved fundamental in determining voids and areas susceptible to sink holes when drilling and are a useful resource for saving time and money for any client.

We can offer the following probe specifications;

Probe	Optical Televiewer (OPTV)
Length	163cm
Diametre	52mm
Borehole	70 to 300mm

Impellor Flowmeter Logging (Ambient and Pumped Conditions)

When determining the permeability of water wells, the impellor flowmeter is an essential tool for measuring fluid flow and the determining highly permeable zones within wells. When there are issues arising with wells there are perfect for determining leakage within the well liner.

Probe	Impellor Flowmeter
Length	0.48mm
Diametre	100mm

Temperature and Conductivity Loggging (Ambient and Pumped Conditions)

Temperature and Conductivity logging is best used in conjunction with the impellor flowmeter whilst in pumped and ambient conditions to best plot groundwater flow. Temperature and conductivity information is fundamental particularly when pumping to help aid permeability estimations.

We can offer the following probe specifications;

Probe	Temperature and Conductivity Probe
Length	0.76mm
Diametre	38mm

Resistivity Logging (Ambient and Pumped Conditions)

Resistivity probe logging is a fantastic tool for determining aquifer lithology and the thickness and identification of rocks. They can be further used to determine groundwater salinity and plot any potential hydrocarbon contamination within major aquifers, an essential tool when working in contaminated land, sensitive areas and difficult ground conditions.

We can offer the following probe specifications;

Probe	Dual Guard Focused Resistivity Sonde
Length	2.37m
Diametre	42mm
LLD & LLS Resistivity	0.2 to 30,000 Ohmm
Range SP Range	2.5V to +2.5V