Jacek Majorowicz | University of Alberta (original) (raw)
CV
Jacek A. Majorowicz, Ph.D., geophysicist specializing in geothermal problems.
Dr. Jacek A. Majorowicz is a citizen of Canada residing in Edmonton, Alberta, Canada.
Professional background
Warsaw University Masters Program, MSsci.1970;
Postgraduate at the Int. Institute Geothermal Res., Pisa, Italy, Geophysics
Geothermics Diploma, 1974
Geological Institute, Warsaw Geophysics Ph.D., 1975
Nat. Res. Eng. Post-doctorate Fellow, Earth Physics Branch, EMR, Ottawa Geophysics 1978-1980
Appointments
Res. Sci. Helmoltz -Alberta Innitiative, Dept. of Physics, Univ. of Alberta, Edmonton, from 2010-2015.
Adjunct Professor, Copernicus University in Torun (Recent appointment April 2012).
Adjunct Professor, University North Dakota, from 2003 (Recent re-appointment Jan. 1, 2012).
Consulting geophysicist, Northern Geothermal Consultants, from 1990 – 2016; Tempest Geophysical, Research Scientist 1985-1990.
Research Scientist, Institute of the Earth and Planetary Sciences. University of Alberta, 1985-1991.
Visiting Professor, Dep. of Physics, Univ. of Alberta, Edmonton, 1982-1984;
Head, Well logging Lab. at the Geophysical Dept. Geological Institute, Warsaw, 1971-1982.
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Papers by Jacek Majorowicz
Przegląd Geologiczny, 1975
The surface temperature forcing is responsible for the majority of the observed deviation of temp... more The surface temperature forcing is responsible for the majority of the observed deviation of temperature with depth. In some cases, differences higher than the error of measurements are observed between the model and measurements. These can be an indication that other factors than surface temperature change influence subsurface temperature. Groundwater flow is one of the possible candidates.
The report presents and discusses data on subsurface temperatures obtained from 595 wells within ... more The report presents and discusses data on subsurface temperatures obtained from 595 wells within the Northern Canadian Sedimentary Basin, concentrated in the Interior Plains from 60 to 63 degrees north latitude and in the Mackenzie Delta. Geothermal gradient values and corresponding effective thermal conductivity values were used to calculate resulting heat flow values which relate to the heat source in the crust and upper mantle. Maps are included showing geothermal gradient, temperature at 500 meters depth, thermal conductivity, heat flow, and subsurface well control. Possible reasons for regional variations and anomalies are discussed.
International Journal of Earth Sciences, Mar 13, 2017
This heat flux has been introduced as a useful new paleoclimate characteristic. It should be dist... more This heat flux has been introduced as a useful new paleoclimate characteristic. It should be distinguished from the steady-state background heat flow. The latter is attributed to the Earth's internal heat sources and does not depends on climate change. Both these fluxes are independent components of the ground surface heat balance. Geothermal reconstructions spanning tens of thousands of years are of special importance for understanding the climate history of the Earth. During this period (15-10-ka BP) the last glacial period of pleistocene (Wisconsinan in central North America, Weichselian or Vistulian in Northern Europe, Valdai in Eastern Europe, Zyryanka and Sartan in Siberia) ended and the current Holocene interglacial began. For long-term geothermal reconstructions, it is necessary to have borehole temperature profiles measured in deep boreholes (>1500 m) with temperature regime restored after drilling. In addition, the boreholes should be drilled in low permeable (e.g., crystalline) rocks with no obvious evidence of convective heat transfer. Ground surface temperature histories for this period were obtained from the analysis of deep borehole temperature profiles (
International Journal of Earth Sciences, Jun 8, 2018
Seismic P-and S-wave velocities of the lower lithosphere and underlying asthenosphere at the SW m... more Seismic P-and S-wave velocities of the lower lithosphere and underlying asthenosphere at the SW margin of the East European Craton in northern Poland were obtained with different seismic techniques: seismic refraction, P-residuals of the first arrivals from teleseismic earthquakes, P-wave receiver function, and inversion of the Rayleigh surface wave dispersion curves, the last two using data collected in the passive seismic experiment "13 BB star". The uniform array consisted of 13 stations deployed in a 120 km in diameter area. Below the depth of 180-220 km a decrease of about 6% of the S-wave velocity is interpreted as a thermal gradient zone corresponding to a lithosphere-asthenosphere transition. The average mantle velocities down to a depth of 300 km beneath the array are relatively high, exceeding values for other Precambrian cratons by 0.1-0.2 km/s, and cannot be modeled by reasonable mantle peridotite compositions in the lithospheric part of the profile. We suggest that significant peridotite anisotropy could explain the misfit between measured and calculated seismic velocities in the lithosphere.
Geothermics, Nov 1, 2020
We examined the potential of geothermal energy to supply power and heat for larger communities (p... more We examined the potential of geothermal energy to supply power and heat for larger communities (population > 10,000) located over the Alberta Basin in the Western Canadian Sedimentary Basin (WCSB). The major cities and seven towns in Alberta examined, with a combined total population of > 2,500,000 people, were scrutinized for their geothermal potential. Depending on T (°C) and production rate (kg/s) the range of households that are feasible to be heated is in the 100's to 1000's for produced water > 70°C and flow rates of 30−80 kg/s. These are available in most of the deep foreland basin in western Alberta and in most of the larger population centers, outside the shallow and 'cold' parts of the basin in the east. As space heating is the dominant energy demand in Canada, with single households representing ∼80% of energy usage, the geothermal heating transition in Alberta would be the best option for municipalities. Power production is feasible in just a few Alberta communities located over the deeper parts of the basin, still requiring > 140°C temperatures and high production rates (> 80 kg/s) due to low efficiency of power plants (some 10%) and economics of the system. The range of the feasible net power production is assessed between single decimals of MW electrical and up to maximum of 2.7 MW in deep hot high production systems.
Przegląd Geologiczny, 1982
Instytut Geologiczny WIELOZNACZNOŚĆ TEKTONICZNEJ INTERPRETACJI ROZKŁADU POLA GEOTERMICZNEGO NA OB... more Instytut Geologiczny WIELOZNACZNOŚĆ TEKTONICZNEJ INTERPRETACJI ROZKŁADU POLA GEOTERMICZNEGO NA OBSZARACH PLATFORMOWYCH POLSKI W ostatnich kilku latach w dziedzinie badań tektonicznych szeroko zaczęto wykorzystywać dane o rozkładzie pola geotermicznego w tektonicznych interpretacjach dla rejonów głębokiego podłoża krystalicznego zakrytego po-86
Przegląd Geologiczny, 1977
International Journal of Earth Sciences, Jan 5, 2019
High-resolution 3D seismic P-wave velocity model of Poland (Grad et al., Tectonophysics 666:188-2... more High-resolution 3D seismic P-wave velocity model of Poland (Grad et al., Tectonophysics 666:188-210, 2016) and corrected for paleoclimate heat flow map (Majorowicz and Wybraniec, Int J Earth Sci 100(4):881-887, 2011) gridded to a common mesh are used together with four independent thermal models of the crust and upper mantle to calculate heat flow variation with depth and geotherms. Heat flow at Moho depth are calculated and mapped and both confirm large variability with an elevated mantle heat flow (circa 30-40 mW/m 2) in the Paleozoic Platform which is some 10-20 mW/m 2 higher than Moho heat flow in the northeastern and southeastern Poland which belong to a variety of tectonic terranes (the oldest Precambrian Craton, younger Cadomian, Trans-European Suture Zone, Carpathians). Temperatures calculated for the crust show consistent pattern: higher temperatures beneath the Paleozoic Platform and lower temperatures beneath the Precambrian and Cadomian units. At 10 km depth this difference is about 150 °C, about 300 °C at 20 km depth, and about 400 °C at 50-60 km. Assuming the calculated isotherm 580 °C as Curie temperature the magnetic crust thickness was determined as 5-10 km only beneath the Polish Basin, circa 20 km in Carpathians, circa 30 km in Sudetes, and 35-40 km beneath the Precambrian and Cadomian units. Such a thick magnetic crust results from a great depth of Curie temperature, thick crystalline crust, and thin sediments. Mantle heat flow variability is mainly correlating with measured surface heat flow and influences geotherms. Calculated thermal LAB depth follows patterns of heat flow and Moho heat flow variability through Poland with thinnest lithosphere in the high surface heat flow and high mantle heat flow areas. Comparison of this thermal LAB depth estimates with seismic data based LAB depth shows general coincidences when Precambrian Craton vs Paleozoic Platform are considered along the P4 seismic experiment data model (circa 190 km depth vs some 90 km depth, respectively). However, significant differences exist in many areas and especially for the SE Poland when compared with map for the whole of Poland compiled from other seismic reported data.
Canadian Journal of Earth Sciences, May 1, 2013
Tectonophysics, Jun 1, 1998
Calculations of the present geothermal gradient and terrestrial heat flow were made on 156 deep w... more Calculations of the present geothermal gradient and terrestrial heat flow were made on 156 deep wells of the Canadian Arctic Archipelago. Corrected bottom hole temperature (BHT) data and drill stem test (DST) temperatures were used to determine the thermal gradients for sites for which the quality of data was sufficient. Thermal gradients evaluated for depths below the base of permafrost
The report presents and discusses data on subsurface temperatures obtained from 595 wells within ... more The report presents and discusses data on subsurface temperatures obtained from 595 wells within the Northern Canadian Sedimentary Basin, concentrated in the Interior Plains from 60 to 63 degrees north latitude and in the Mackenzie Delta. Geothermal gradient values and corresponding effective thermal conductivity values were used to calculate resulting heat flow values which relate to the heat source in the crust and upper mantle. Maps are included showing geothermal gradient, temperature at 500 meters depth, thermal conductivity, heat flow, and subsurface well control. Possible reasons for regional variations and anomalies are discussed.
GEOTHERMAL PARAMETERS OF THE KRZEMIANKA AND UDRYŃ AREA ON THE BACKGROUND OF THE THERMAL FIELD OF ... more GEOTHERMAL PARAMETERS OF THE KRZEMIANKA AND UDRYŃ AREA ON THE BACKGROUND OF THE THERMAL FIELD OF NE POLAND Summary The paper presents results of geothermal studies covering the area of NW-Polish section of the East European Precambrian Platform. The measurements taken in the areas of Krzemianka and Udryn, where boreholes about 2.2 km deep penetrated a 1.4 km section of Precambrian intrusive iron-bearing norite-anorthosite rocks, are analysed in detail. Values of heat flow and the geothermal gradient are determined for these areas. Table III shows newly obtained as well as already published heat flow values. Tables I and II show temperatures recorded at various depth and geothermal gradients determined for the areas of Krzemianka and Udryn. An analysis of geothermograms from Krzemianka and Udryn boreholes has shown the occurrence of disturbances in the heat field at the depths to 0.6 km. The disturbances are related to successive glaciation epochs and to the Holocene period of climat...
Geothermics, 2020
We examined the potential of geothermal energy to supply power and heat for larger communities (p... more We examined the potential of geothermal energy to supply power and heat for larger communities (population > 10,000) located over the Alberta Basin in the Western Canadian Sedimentary Basin (WCSB). The major cities and seven towns in Alberta examined, with a combined total population of > 2,500,000 people, were scrutinized for their geothermal potential. Depending on T (°C) and production rate (kg/s) the range of households that are feasible to be heated is in the 100's to 1000's for produced water > 70°C and flow rates of 30−80 kg/s. These are available in most of the deep foreland basin in western Alberta and in most of the larger population centers, outside the shallow and 'cold' parts of the basin in the east. As space heating is the dominant energy demand in Canada, with single households representing ∼80% of energy usage, the geothermal heating transition in Alberta would be the best option for municipalities. Power production is feasible in just a few Alberta communities located over the deeper parts of the basin, still requiring > 140°C temperatures and high production rates (> 80 kg/s) due to low efficiency of power plants (some 10%) and economics of the system. The range of the feasible net power production is assessed between single decimals of MW electrical and up to maximum of 2.7 MW in deep hot high production systems.
International Journal of Earth Sciences, 2018
Seismic P-and S-wave velocities of the lower lithosphere and underlying asthenosphere at the SW m... more Seismic P-and S-wave velocities of the lower lithosphere and underlying asthenosphere at the SW margin of the East European Craton in northern Poland were obtained with different seismic techniques: seismic refraction, P-residuals of the first arrivals from teleseismic earthquakes, P-wave receiver function, and inversion of the Rayleigh surface wave dispersion curves, the last two using data collected in the passive seismic experiment "13 BB star". The uniform array consisted of 13 stations deployed in a 120 km in diameter area. Below the depth of 180-220 km a decrease of about 6% of the S-wave velocity is interpreted as a thermal gradient zone corresponding to a lithosphere-asthenosphere transition. The average mantle velocities down to a depth of 300 km beneath the array are relatively high, exceeding values for other Precambrian cratons by 0.1-0.2 km/s, and cannot be modeled by reasonable mantle peridotite compositions in the lithospheric part of the profile. We suggest that significant peridotite anisotropy could explain the misfit between measured and calculated seismic velocities in the lithosphere.
AN ANALYSIS OF GEOTHERMAL FIELD OF POLAND ON THE BACKGROUND OF EUROPE, WITH A SPECIAL ATTENTION P... more AN ANALYSIS OF GEOTHERMAL FIELD OF POLAND ON THE BACKGROUND OF EUROPE, WITH A SPECIAL ATTENTION PAID TO TECTONOPHYSICAL AND HYDROTERMAL PROBLEMS Summary A map of heat flow in Poland and surrounding areas and maps of geothermal gradient and geoisoterms from 1 km and 2 km depths are given. The image of distribution of heat flow in Poland was included to the geothermal map of Europe (31). The problem of interpretation of distribution of geothermal field of Poland versus that of Europe was analysed taking into account the problems of tectonophysics and the knowledge of hydrogeothermal potential. The analysis of several facts concerning the heat field, seismoIogical structure of Earth crust and upper mantle as well as the history of tectonic development of Poland and Europe has shown that differences in values of heat flow for geotectonic areas of different age are presumably related to differences in values of subcrustal Earth heat flow which is generally higher in tectonically younger ...
Przegląd Geologiczny, 1975
The surface temperature forcing is responsible for the majority of the observed deviation of temp... more The surface temperature forcing is responsible for the majority of the observed deviation of temperature with depth. In some cases, differences higher than the error of measurements are observed between the model and measurements. These can be an indication that other factors than surface temperature change influence subsurface temperature. Groundwater flow is one of the possible candidates.
The report presents and discusses data on subsurface temperatures obtained from 595 wells within ... more The report presents and discusses data on subsurface temperatures obtained from 595 wells within the Northern Canadian Sedimentary Basin, concentrated in the Interior Plains from 60 to 63 degrees north latitude and in the Mackenzie Delta. Geothermal gradient values and corresponding effective thermal conductivity values were used to calculate resulting heat flow values which relate to the heat source in the crust and upper mantle. Maps are included showing geothermal gradient, temperature at 500 meters depth, thermal conductivity, heat flow, and subsurface well control. Possible reasons for regional variations and anomalies are discussed.
International Journal of Earth Sciences, Mar 13, 2017
This heat flux has been introduced as a useful new paleoclimate characteristic. It should be dist... more This heat flux has been introduced as a useful new paleoclimate characteristic. It should be distinguished from the steady-state background heat flow. The latter is attributed to the Earth's internal heat sources and does not depends on climate change. Both these fluxes are independent components of the ground surface heat balance. Geothermal reconstructions spanning tens of thousands of years are of special importance for understanding the climate history of the Earth. During this period (15-10-ka BP) the last glacial period of pleistocene (Wisconsinan in central North America, Weichselian or Vistulian in Northern Europe, Valdai in Eastern Europe, Zyryanka and Sartan in Siberia) ended and the current Holocene interglacial began. For long-term geothermal reconstructions, it is necessary to have borehole temperature profiles measured in deep boreholes (>1500 m) with temperature regime restored after drilling. In addition, the boreholes should be drilled in low permeable (e.g., crystalline) rocks with no obvious evidence of convective heat transfer. Ground surface temperature histories for this period were obtained from the analysis of deep borehole temperature profiles (
International Journal of Earth Sciences, Jun 8, 2018
Seismic P-and S-wave velocities of the lower lithosphere and underlying asthenosphere at the SW m... more Seismic P-and S-wave velocities of the lower lithosphere and underlying asthenosphere at the SW margin of the East European Craton in northern Poland were obtained with different seismic techniques: seismic refraction, P-residuals of the first arrivals from teleseismic earthquakes, P-wave receiver function, and inversion of the Rayleigh surface wave dispersion curves, the last two using data collected in the passive seismic experiment "13 BB star". The uniform array consisted of 13 stations deployed in a 120 km in diameter area. Below the depth of 180-220 km a decrease of about 6% of the S-wave velocity is interpreted as a thermal gradient zone corresponding to a lithosphere-asthenosphere transition. The average mantle velocities down to a depth of 300 km beneath the array are relatively high, exceeding values for other Precambrian cratons by 0.1-0.2 km/s, and cannot be modeled by reasonable mantle peridotite compositions in the lithospheric part of the profile. We suggest that significant peridotite anisotropy could explain the misfit between measured and calculated seismic velocities in the lithosphere.
Geothermics, Nov 1, 2020
We examined the potential of geothermal energy to supply power and heat for larger communities (p... more We examined the potential of geothermal energy to supply power and heat for larger communities (population > 10,000) located over the Alberta Basin in the Western Canadian Sedimentary Basin (WCSB). The major cities and seven towns in Alberta examined, with a combined total population of > 2,500,000 people, were scrutinized for their geothermal potential. Depending on T (°C) and production rate (kg/s) the range of households that are feasible to be heated is in the 100's to 1000's for produced water > 70°C and flow rates of 30−80 kg/s. These are available in most of the deep foreland basin in western Alberta and in most of the larger population centers, outside the shallow and 'cold' parts of the basin in the east. As space heating is the dominant energy demand in Canada, with single households representing ∼80% of energy usage, the geothermal heating transition in Alberta would be the best option for municipalities. Power production is feasible in just a few Alberta communities located over the deeper parts of the basin, still requiring > 140°C temperatures and high production rates (> 80 kg/s) due to low efficiency of power plants (some 10%) and economics of the system. The range of the feasible net power production is assessed between single decimals of MW electrical and up to maximum of 2.7 MW in deep hot high production systems.
Przegląd Geologiczny, 1982
Instytut Geologiczny WIELOZNACZNOŚĆ TEKTONICZNEJ INTERPRETACJI ROZKŁADU POLA GEOTERMICZNEGO NA OB... more Instytut Geologiczny WIELOZNACZNOŚĆ TEKTONICZNEJ INTERPRETACJI ROZKŁADU POLA GEOTERMICZNEGO NA OBSZARACH PLATFORMOWYCH POLSKI W ostatnich kilku latach w dziedzinie badań tektonicznych szeroko zaczęto wykorzystywać dane o rozkładzie pola geotermicznego w tektonicznych interpretacjach dla rejonów głębokiego podłoża krystalicznego zakrytego po-86
Przegląd Geologiczny, 1977
International Journal of Earth Sciences, Jan 5, 2019
High-resolution 3D seismic P-wave velocity model of Poland (Grad et al., Tectonophysics 666:188-2... more High-resolution 3D seismic P-wave velocity model of Poland (Grad et al., Tectonophysics 666:188-210, 2016) and corrected for paleoclimate heat flow map (Majorowicz and Wybraniec, Int J Earth Sci 100(4):881-887, 2011) gridded to a common mesh are used together with four independent thermal models of the crust and upper mantle to calculate heat flow variation with depth and geotherms. Heat flow at Moho depth are calculated and mapped and both confirm large variability with an elevated mantle heat flow (circa 30-40 mW/m 2) in the Paleozoic Platform which is some 10-20 mW/m 2 higher than Moho heat flow in the northeastern and southeastern Poland which belong to a variety of tectonic terranes (the oldest Precambrian Craton, younger Cadomian, Trans-European Suture Zone, Carpathians). Temperatures calculated for the crust show consistent pattern: higher temperatures beneath the Paleozoic Platform and lower temperatures beneath the Precambrian and Cadomian units. At 10 km depth this difference is about 150 °C, about 300 °C at 20 km depth, and about 400 °C at 50-60 km. Assuming the calculated isotherm 580 °C as Curie temperature the magnetic crust thickness was determined as 5-10 km only beneath the Polish Basin, circa 20 km in Carpathians, circa 30 km in Sudetes, and 35-40 km beneath the Precambrian and Cadomian units. Such a thick magnetic crust results from a great depth of Curie temperature, thick crystalline crust, and thin sediments. Mantle heat flow variability is mainly correlating with measured surface heat flow and influences geotherms. Calculated thermal LAB depth follows patterns of heat flow and Moho heat flow variability through Poland with thinnest lithosphere in the high surface heat flow and high mantle heat flow areas. Comparison of this thermal LAB depth estimates with seismic data based LAB depth shows general coincidences when Precambrian Craton vs Paleozoic Platform are considered along the P4 seismic experiment data model (circa 190 km depth vs some 90 km depth, respectively). However, significant differences exist in many areas and especially for the SE Poland when compared with map for the whole of Poland compiled from other seismic reported data.
Canadian Journal of Earth Sciences, May 1, 2013
Tectonophysics, Jun 1, 1998
Calculations of the present geothermal gradient and terrestrial heat flow were made on 156 deep w... more Calculations of the present geothermal gradient and terrestrial heat flow were made on 156 deep wells of the Canadian Arctic Archipelago. Corrected bottom hole temperature (BHT) data and drill stem test (DST) temperatures were used to determine the thermal gradients for sites for which the quality of data was sufficient. Thermal gradients evaluated for depths below the base of permafrost
The report presents and discusses data on subsurface temperatures obtained from 595 wells within ... more The report presents and discusses data on subsurface temperatures obtained from 595 wells within the Northern Canadian Sedimentary Basin, concentrated in the Interior Plains from 60 to 63 degrees north latitude and in the Mackenzie Delta. Geothermal gradient values and corresponding effective thermal conductivity values were used to calculate resulting heat flow values which relate to the heat source in the crust and upper mantle. Maps are included showing geothermal gradient, temperature at 500 meters depth, thermal conductivity, heat flow, and subsurface well control. Possible reasons for regional variations and anomalies are discussed.
GEOTHERMAL PARAMETERS OF THE KRZEMIANKA AND UDRYŃ AREA ON THE BACKGROUND OF THE THERMAL FIELD OF ... more GEOTHERMAL PARAMETERS OF THE KRZEMIANKA AND UDRYŃ AREA ON THE BACKGROUND OF THE THERMAL FIELD OF NE POLAND Summary The paper presents results of geothermal studies covering the area of NW-Polish section of the East European Precambrian Platform. The measurements taken in the areas of Krzemianka and Udryn, where boreholes about 2.2 km deep penetrated a 1.4 km section of Precambrian intrusive iron-bearing norite-anorthosite rocks, are analysed in detail. Values of heat flow and the geothermal gradient are determined for these areas. Table III shows newly obtained as well as already published heat flow values. Tables I and II show temperatures recorded at various depth and geothermal gradients determined for the areas of Krzemianka and Udryn. An analysis of geothermograms from Krzemianka and Udryn boreholes has shown the occurrence of disturbances in the heat field at the depths to 0.6 km. The disturbances are related to successive glaciation epochs and to the Holocene period of climat...
Geothermics, 2020
We examined the potential of geothermal energy to supply power and heat for larger communities (p... more We examined the potential of geothermal energy to supply power and heat for larger communities (population > 10,000) located over the Alberta Basin in the Western Canadian Sedimentary Basin (WCSB). The major cities and seven towns in Alberta examined, with a combined total population of > 2,500,000 people, were scrutinized for their geothermal potential. Depending on T (°C) and production rate (kg/s) the range of households that are feasible to be heated is in the 100's to 1000's for produced water > 70°C and flow rates of 30−80 kg/s. These are available in most of the deep foreland basin in western Alberta and in most of the larger population centers, outside the shallow and 'cold' parts of the basin in the east. As space heating is the dominant energy demand in Canada, with single households representing ∼80% of energy usage, the geothermal heating transition in Alberta would be the best option for municipalities. Power production is feasible in just a few Alberta communities located over the deeper parts of the basin, still requiring > 140°C temperatures and high production rates (> 80 kg/s) due to low efficiency of power plants (some 10%) and economics of the system. The range of the feasible net power production is assessed between single decimals of MW electrical and up to maximum of 2.7 MW in deep hot high production systems.
International Journal of Earth Sciences, 2018
Seismic P-and S-wave velocities of the lower lithosphere and underlying asthenosphere at the SW m... more Seismic P-and S-wave velocities of the lower lithosphere and underlying asthenosphere at the SW margin of the East European Craton in northern Poland were obtained with different seismic techniques: seismic refraction, P-residuals of the first arrivals from teleseismic earthquakes, P-wave receiver function, and inversion of the Rayleigh surface wave dispersion curves, the last two using data collected in the passive seismic experiment "13 BB star". The uniform array consisted of 13 stations deployed in a 120 km in diameter area. Below the depth of 180-220 km a decrease of about 6% of the S-wave velocity is interpreted as a thermal gradient zone corresponding to a lithosphere-asthenosphere transition. The average mantle velocities down to a depth of 300 km beneath the array are relatively high, exceeding values for other Precambrian cratons by 0.1-0.2 km/s, and cannot be modeled by reasonable mantle peridotite compositions in the lithospheric part of the profile. We suggest that significant peridotite anisotropy could explain the misfit between measured and calculated seismic velocities in the lithosphere.
AN ANALYSIS OF GEOTHERMAL FIELD OF POLAND ON THE BACKGROUND OF EUROPE, WITH A SPECIAL ATTENTION P... more AN ANALYSIS OF GEOTHERMAL FIELD OF POLAND ON THE BACKGROUND OF EUROPE, WITH A SPECIAL ATTENTION PAID TO TECTONOPHYSICAL AND HYDROTERMAL PROBLEMS Summary A map of heat flow in Poland and surrounding areas and maps of geothermal gradient and geoisoterms from 1 km and 2 km depths are given. The image of distribution of heat flow in Poland was included to the geothermal map of Europe (31). The problem of interpretation of distribution of geothermal field of Poland versus that of Europe was analysed taking into account the problems of tectonophysics and the knowledge of hydrogeothermal potential. The analysis of several facts concerning the heat field, seismoIogical structure of Earth crust and upper mantle as well as the history of tectonic development of Poland and Europe has shown that differences in values of heat flow for geotectonic areas of different age are presumably related to differences in values of subcrustal Earth heat flow which is generally higher in tectonically younger ...