Carburization effects on pig iron nugget making, B. Anameric, K.B. ...
Dr. K.B. McManus, University of Durham Dr. D.N.M. Donoghue, University of Durham
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Transcript of Dr. K.B. McManus, University of Durham Dr. D.N.M. Donoghue, University of Durham
Airborne thermography and ground geophysical investigation for detecting
shallow ground disturbance
Dr. K.B. McManus, University of Durham
Dr. D.N.M. Donoghue, University of Durham
Dr. S.H. Marsh, British Geological Survey
Dr. C. Brooke, Leicestershire County Council
Physical Context
Soil Marksvariation in mineralogyand moisture properties
Crop Marksvariation in vegetation health
Differential Crop Marksconstraint on root depthand moisture availability
How do materials respond to solar heating?
12:00
Temperature
00:00 24:00
Time
bare soil
water
vegetation
Physical and Apparent Thermal Inertia
• Physical Thermal Inertia (TI)– Response to temperature change– Physical TI = √(density*thermal conductivity*heat capacity)
• Apparent Thermal Inertia (ATI)– ATI = (1-albedo) / (Temperature max - Temperature min)– Thermal image pair solar noon and pre-dawn
12:00
Temperature
00:00 24:00Time
bare soil
water
vegetation
Comparison of visible, near-infrared and thermal
DayTIR
NightTIR
False ColourComposite
NIR:VISR:VISG
Natural ColourComposite
VISR:VISG:VISB
TIR -v- Geophysical Properties (1)Buried archaeology at Bosworth, Leics.
Apparent Thermal Inertia Magnetometry
Characteristics of thermal response of soil
0
5
10
15
20
25
0 360 720 1080 1440
Time (min)
Tem
pera
ture
(C
)
Surface
10cm
20cm
50cm
TIR -v- Geophysical Properties (2)Topographic feature on Baildon Moor, W. Yorks.
Thermal profile Electromagnetic profile
TIR -v- Geophysical Properties (3)Vegetation feature on Baildon Moor, W. Yorks.
Thermal profile Resistivity profile
TIR –v- Soil properties
FEATURE B
Thermal Anomaly
FEATURE C
Thermal and Geophysical
Anomaly
Conclusions
• Thermal imaging during the day or night can enhance detection of anomalous materials compared to visible and near-infrared imaging
• Contrast between thermal images also enhances anomaly detection with sensitivity to bulk variations
• Comparison of thermal images with physical soil parameters suggest– Thermal response beneath vegetation sensitive to diurnal
variations shallower than 0.50m (thermal profiling)
– Good correlation with topographic features due to differential solar heating
– Good correlation with moisture properties (resistivity and soil samples)