Electrical conductivity of carbonbearing granulite at raised temperatures and pressures

@article{Glover1992ElectricalCO,
  title={Electrical conductivity of carbonbearing granulite at raised temperatures and pressures},
  author={Paul W. J. Glover and Frederick John Vine},
  journal={Nature},
  year={1992},
  volume={360},
  pages={723-726}
}
IT has long been recognized that the electrical conductivity of the lower continental crust is anomalously high. Both pore-saturating brines1–5 and conducting films of carbon at grain boundaries6–10 have been proposed to explain this, but the evidence remains inconclusive. Here we report measurements of electrical conductivity at high temperatures and pressures11–13 on samples of carbon-bearing and carbon-free granulites with a range of electrolyte saturations. The application of pressure to… Expand
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Electrical conductivity measurements were made on black shale samples from deep boreholes under laboratory conditions corresponding to more than 10 km burial depth. At these conditions, largeExpand
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[1] The electrical conductivity of lower crustal clinopyroxene was measured at 6–12 kbar, 250–1000°C, and Ni-NiO buffer conditions. The dependence of electrical conductivity on water content wasExpand
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Abstract A high conductivity zone (HCZ) exists in many places worldwide in the stable mid- to lower continental crust, at the depth of about 20–30 km, but its origin is enigmatic. At this depthExpand
Evidence from borehole samples for the role of accessory minerals in lower-crustal conductivity
THE high electrical conductivity of the lower continental crust, as inferred from geophysical measurements1, has defied a simple explanation. Both pore-saturating brines2 and interconnected carbonExpand
Electrical conductivity and carbon in metamorphic rocks of the Yukon-Tanana Terrane, Alaska
Electrical conductivity of a water-saturated quartz-mica-garnet-schist, collected from a surface outcrop near the Denali Fault Zone in the Yukon-Tanana terrane of east central Alaska, increasesExpand
Electrical Conductivity of Rocks and Dominant Charge Carriers: The Paradox of Thermally Activated Positive Holes
In this paper we have focused on fundamental processes that are important for understanding the electrical properties of materials, both single crystal minerals and igneous rocks, bothExpand
Electrical conductivity measurement of gneiss under mid- to lower crustal P–T conditions
Abstract We conducted electrical conductivity measurements perpendicular and parallel to mineral foliation in dry gneiss at up to 1000 K and a constant pressure of 1 GPa. The analyzed gneisses wereExpand
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Abstract In the present work, complex electrical conductivity measurements in the frequency range of 10 mHz–1 MHz and at elevated temperatures (423 K–1373 K) were carried out in amphibolite sample,Expand
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THE origin of zones of high electrical conductivity in the lower continental crust is a long-standing mystery; possible explanations include the presence of brines1,2, partial melt3, serpentine4 andExpand
Electrical conductivity models for the continental crust based on laboratory measurements on high-grade metamorphic rocks
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Grain-boundary graphite in Kapuskasing gneisses and implications for lower-crustal conductivity
SURFACE electromagnetic measurements commonly reveal that the intermediate and lower continental crust has an appreciable electrical conductivity, much higher than that found for laboratory analoguesExpand
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Primary carbonaceous material has been identified in submarine basaltic glasses and mantle-derived peridotite nodules from alkali basalts using electron microprobe techniques. In the submarine rocksExpand
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SUMMARY Magnetotelluric and multichannel seismic reflection measurements indicate that the Phanerozoic lower continental crust is commonly electrically conductive and reflective, in contrast to aExpand
Impedance of black shale from Münsterland 1 borehole: an anomalously good conductor?
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