Analysis of Heat Flow Data–Vertical Variations of Heat Flow and Heat Producing Elements in Sediments

1975 ◽  
Vol 12 (6) ◽  
pp. 996-1005 ◽  
Author(s):  
V. M. Hamza ◽  
A. E. Beck
Keyword(s):  
Heat Flow ◽  
Heat Production ◽  
Gamma Ray ◽  
Detailed Examination ◽  
Uranium Content ◽  
Thermal Resistivity ◽  
Geochemical Reactions ◽  
Vertical Variations ◽  
Heat Flow Variations

Gamma ray spectrometric techniques have been used for the determination of uranium, thorium and potassium contents from cores selected at 3 to 4 m intervals from a 600 m deep borehole in sedimentary formations and the results compared with a similarly detailed examination of heat flow, and some physical properties, from the same borehole.The results indicate a broad positive correlation between thermal resistivity and some of the radio-element parameters and between heat flow and heat production. The heat production variations down the borehole are not quantitatively sufficient to explain the observed heat flow variations. The uranium series appears to be in radioactive equilibrium even in those sections where the uranium content is low, the porosity relatively high and the heat flow low; it is therefore concluded that the depletion of uranium is due to an ancient rather than a recent leaching process and that it is unlikely that the heat flow variations along the borehole are due to existing or recent underground waterflows. Long term geochemical reactions are now thought to be the most likely explanation of the heat flow variations.

Heat flow and surface radioactivity in the Quirke Lake Syncline near Elliot Lake, Ontario, Canada

1968 ◽  
Vol 5 (6) ◽  
pp. 1417-1428 ◽  
Author(s):  
J. H. Sass ◽  
P. G. Killeen ◽  
E. D. Mustonen
Keyword(s):  
Heat Flow ◽  
Heat Production ◽  
Gamma Ray ◽  
Average Rate ◽  
Structural Effects ◽  
Gamma Ray Spectrometer ◽  
A Value ◽  
The Mean ◽  
Data Yield ◽  
Ore Zones

Heat flow was measured in seven diamond-drilled holes, ranging in depth from 300 to 900 m, in the Quirke Lake Syncline (82° 30′ W, 46° 30′ N, mean elevation 370 m), Values for individual holes vary from 1.20 to 1.40 with a mean of 1.32 ± 0.02 μcal/cm2s, and no systematic variation was detected within the 50 km2 area studied. Radiometric measurements with a portable, three-channel, gamma-ray spectrometer show a downward concentration (stratigraphically) of Th, U, and K within the lower part of the syncline, with mean concentrations of 12.7 ppm, 3.3 ppm, and 1.9%, respectively. These data yield an average rate of heat production of 4.5 heat generation units (1 hgu = 10−13 cal/cm3s). Taking account of the ore zones, the mean heat production from the syncline is about 6 hgu. Corrections for structural effects and heat production from the ore result in a value of 1.2 for the regional heat flow. This is within the range of other shield values, although somewhat higher than the average for the Canadian Shield. The high value is readily explained if the observed mean surface radioactivity persists to a depth of 7 to 10 km.

Analysis of heat flow data—correlation of thermal resistivity and shock metamorphic grade and its use as evidence for an impact origin of the Brent Crater

1976 ◽  
Vol 13 (7) ◽  
pp. 929-936 ◽  
Author(s):  
A. E. Beck ◽  
V. M. Hamza ◽  
C. C. Chang
Keyword(s):  
Heat Flow ◽  
Heat Production ◽  
Metamorphic Grade ◽  
Stable Region ◽  
Thermal Resistivity ◽  
Deep Borehole ◽  
Meteorite Impact ◽  
Production Values ◽  
Impact Origin ◽  
Impact Hypothesis

Measurements of heat flow and radioactive heat generation values have been made at small intervals using a completely cored, 1 km deep borehole located close to the center of the Brent Crater. A remarkable correlation is observed between the thermal resistivity values and shock metamorphic grade. This is interpreted as due to residual shock effects on the lattice conductivity. These effects are preserved over long periods of time, probably because of rapid cooling that prevented thermal annealing and recrystallization. The highly shock metamorphosed samples also have characteristically low heat production values, resulting from a depletion of thorium and uranium; potassium distribution is fairly uniform except at the boundaries of metamorphic zones, where it is enriched to a considerable degree. These results support the meteorite impact hypothesis for the origin of the crater.Mean heat production and corrected heat flow values obtained for this borehole are 1.51 ± 0.57 μWm−3 (3.6 ± 1.4 HPU) and 41.9 ± 6.3 mWm−2 (1.00 ± 0.15 HFU), respectively. These values indicate that this region may belong or be similar to the Central Stable region heat flow province.

scholarly journals A union neutron-gamma logging method for determination of uranium-radium disequilibrium coefficient

2020 ◽  
Vol 35 (2) ◽  
pp. 103-108
Author(s):  
Rui Chen ◽  
Cheng-Yuan Luo ◽  
Hai-Tao Wang ◽  
Zhi-Feng Liu ◽  
Xiong-Jie Zhang ◽  
...  
Keyword(s):  
Count Rate ◽  
Gamma Ray ◽  
Uranium Content ◽  
Fission Neutron ◽  
Characteristic Peak ◽  
Prompt Fission ◽  
Logging Tool ◽  
Peak Count ◽  
Good Agreement

Owing to the influence of continuous running of ground water, the uranium atoms can be separated physically from their daughters for the reason of different solubilities and the uranium deposit often shows the disequilibrium feature between uranium and its daughter products (radium principally). It is important, when spectral gamma ray logging, to quantify the uranium content which can cause inaccuracy of the result. This paper, based on spectral ? ray logging method, proposes a neutron-gamma logging method to determine the coefficient of uranium-radium disequilibrium. In this method, characteristic peak count rate of uranium is taken from prompt fission neutron logging, whereas characteristic peak count rate of radium, thorium and potassium are taken from spectral gamma ray logging. Based on this method, the union logging tool including epithermal neutron, thermal neutron, and gamma detector along with D-T generator, have been developed. The experimental results, in standard model wells, show that this method is in good agreement within 7% in core assay results. It shows that the union neutron-? logging method can be used for field uranium logging jobs.

Deep Drill 1972. Heat Flow and Heat Production in Bermuda

1974 ◽  
Vol 11 (6) ◽  
pp. 809-818 ◽  
Author(s):  
R. D. Hyndman ◽  
G. K. Muecke ◽  
F. Aumento
Keyword(s):  
Heat Flux ◽  
Heat Flow ◽  
Heat Production ◽  
Land Surface ◽  
Gamma Ray ◽  
Gamma Ray Spectrometry ◽  
Geothermal Heat ◽  
Sea Floor ◽  
Average Value ◽  
The Mean

The geothermal heat flux determined in a borehole on Bermuda is 1.36 μcal/cm2 s (57 mW/m2). The value is corrected for the topographic effect of the Bermuda sea-mount and the difference between sea floor and land surface temperatures. Radioactive heat production in the borehole core determined by gamma-ray spectrometry has an average value of 1.45 × 10−13 cal/cm3 s (6.11 × 10−7 W/m3). Of the altered tholeiite flows and intrusive lamprophyric sheets which make up the section to 800 m, the sheets have 10 times the heat production of the flows. If the heat production attributable to the Bermuda seamount is subtracted from the measured heat flux a value of 1.26 μcal/cm2 s (53 mW/m2) is obtained which is in good agreement with the mean of surrounding sea floor measurements and with the mean for Cretaceous ocean floor. The low heat flow and the small amount of subsidence substantiates the radioactive dating data which indicates the present seamount structure was produced about 33 m.y. ago by intrusion and uplift of a much older structure.

Sign in / Sign up

Export Citation Format

Share Document