PROPAGATION OF RADIO FREQUENCY ENERGY THROUGH THE EARTH

Geophysics ◽  
1954 ◽  
Vol 19 (3) ◽  
pp. 459-477 ◽  
Author(s):  
F. M. McGehee
Keyword(s):  
New Mexico ◽  
Radio Frequency ◽  
Propagation Characteristics ◽  
Attenuation Constant ◽  
Radio Frequency Energy ◽  
The Earth ◽  
Similar Series ◽  
Set Up ◽  
Good Agreement ◽  
Made In

Measurements have been made of some propagation characteristics in the earth of 1,614 and 1,700 kc radio frequency energy. The experiments were conducted at Carlsbad Caverns, New Mexico, and Mammoth Cave, Kentucky. Transmitters were set up on the surface 710 ft above an unwired tunnel in Carlsbad Caverns and the signal strength was measured at many points in the tunnels. A similar series of measurements was made in Mammoth Cave in a tunnel 270 ft below the surface. The data show that the attenuation constant is about 0.012 and 0.02 to 0.064 neper/meter at the two locations respectively. These values are in good agreement with theory.

A RESISTIVITY SURVEY OF THE MONUMENT OIL FIELD

Geophysics ◽  
1943 ◽  
Vol 8 (1) ◽  
pp. 14-22
Author(s):  
C. M. England
Keyword(s):  
Electrical Resistivity ◽  
New Mexico ◽  
Oil Field ◽  
Red Beds ◽  
Electrical Resistivity Survey ◽  
Resistivity Survey ◽  
Good Agreement ◽  
Made In

This paper describes an electrical resistivity survey made in 1935 of an area in New Mexico now known as the Monument Field. From the data obtained a map showing the structure at the base of the Red Beds was prepared which is in good agreement with structure disclosed by wells later drilled.

A Royal Society appointment with Venus in 1769: the voyage of Cook and Banks in the Endeavour In 1768-1771 and its botanical results

1969 ◽  
Vol 24 (1) ◽  
pp. 64-90 ◽  
Keyword(s):  
Pacific Ocean ◽  
Royal Society ◽  
The Sun ◽  
Royal Navy ◽  
The Earth ◽  
The Pacific ◽  
The Pacific Ocean ◽  
Set Up ◽  
George Iii ◽  
Made In

A little over two hundred years ago a number of serious and learned men in Copenhagen, London, Paris, St Petersbourg, Stockholm and elsewhere, men who were academicians, Fellows of the Royal Society, Lords of the Admiralty, politicians and the like, had been thinking seriously and learnedly about the behaviour of Venus, not, of course, about Venus as represented coldly and chastely by the marble statues being imported from Italy or more warmly in the paintings of Boucher and his contemporaries, but about her far distant planet which was calculated to pass across the disk of the Sun in 1769 and not to make another such transit until 1874. Observations of the 1769 transit at widely separated stations would provide, it was hoped, the means of calculating the distance of the Earth from the Sun. The Royal Society in London, having set up in November 1767 a sub-committee ‘to consider the places proper to observe the coming Transit of Venus’ and other particulars relevant to the same, presented a memorial to King George III outlining possible benefits to science and navigation from observations made in the Pacific Ocean and received in return the promise of £4000 and a suitable ship provided by the Royal Navy (8).

ATTENUATION OF RADIO FREQUENCY WAVES THROUGH THE EARTH

Geophysics ◽  
1952 ◽  
Vol 17 (2) ◽  
pp. 193-217 ◽  
Author(s):  
W. C. Pritchett
Keyword(s):  
Radio Frequency ◽  
Normal Values ◽  
Electromagnetic Theory ◽  
Deep Penetration ◽  
Radio Waves ◽  
Attenuation Constant ◽  
A Value ◽  
The Earth ◽  
Radio Frequency Waves

Evidence has been presented by several investigators indicating the possibility that radio waves penetrate sufficiently deep into the earth to be useful in prospecting for oil. Conventional electromagnetic theory used with normal values of the earth constants indicates, however, that the attenuation is too great to allow the signal to be used after propagation through significant distances of shale. To settle the above question an experiment was conceived and carried out in which the signal level in the earth was measured at various distances from a battery‐operated transmitter operating at 1,652 kc suspended in an uncased, mud‐filled hole by a mud‐saturated rope. The mud resistivity was matched to that of the 40 foot thick shale section used in order that the entire immediate region would be as nearly as possibly homogeneous. The receiver was also battery‐operated and suspended by a cable in other similar mud‐filled holes at various distances from the first hole. The attenuation constant in shale was found to be 0.231 nepers/foot (2 db/foot), which is much too large to give any hope of deep penetration. A few measurements in a limestone section gave a value of 0.086 nepers/foot, which is also too large to be useful. Although these values are quite high, they are lower than theory predicts for these earth resistivities by a factor of about two.

scholarly journals The transmission of electric waves over the surface of the Earth

1915 ◽  
Vol 91 (627) ◽  
pp. 219-219
Keyword(s):  
Sea Water ◽  
Wave Length ◽  
Diffraction Theory ◽  
Small Extent ◽  
The Earth ◽  
Similar Series ◽  
Moderate Resistance ◽  
Perfect Conduction ◽  
Electric Waves ◽  
Good Agreement

An analytical solution of the general equation of electrodynamics is obtained for the case of waves generated by a vibrating doublet in presence of a conducting sphere, and is adapted to obtain the known solution for perfect conduction, and the correction for moderate resistance, such as that of sea-water. The known solution is expressed by the sum of a series involving zonal harmonics, and the correction by a similar series. Different results have been obtained by different writers who have investigated the numerical value of the former sum. In the paper a new method of summing the series is explained, and worked out in detail for the wave-length 5 km. In the case of perfect conduction the result confirms that found by H. M. Macdonald. The effect of resistance is found to be a slight increase of the strength of the signals at considerable distances, counteracting to some small extent the enfeebling effect of the curvature of the surface. A comparison is instituted between the results of the theory and those of recorded experiments. From these it had previously been inferred that the diffraction theory fails to account for the facts; but, after a discussion of the experimental evidence, it appears that the observations may admit of a different interpretation, according to which the results of the diffraction theory would be in good agreement with those of daylight observations at great distances.

New Mexico

2017 ◽  
Author(s):  
David K. Jones
Keyword(s):  
New Mexico ◽  
Board Of Directors ◽  
The State ◽  
Governance Model ◽  
The Board Of Directors ◽  
Set Up ◽  
The Right

The fight over an exchange had a very different dynamic in New Mexico because there were no loud voices on the right calling for the state to reject control. Republican Governor Susanna Martinez supported retaining control, but strongly preferred a governance model that allowed insurers to serve on the board of directors and limited the degree of oversight by the board on the types of plans that could be sold on the exchange. Governor Martinez vetoed legislation in 2011 that would have set up a different model of an exchange. Institutional quirks meant the legislature did not have the opportunity to weigh in again for two years, until 2013. By this point it was too late and the state had to rely on the federal website despite passing legislation to run its own exchange.

scholarly journals Laboratory Measurements of Light Scattering by Dust Particles

1996 ◽  
Vol 150 ◽  
pp. 409-413
Author(s):  
Patrick P. Combet ◽  
Philippe L. Lamy
Keyword(s):  
Light Scattering ◽  
Laser Beam ◽  
Mie Theory ◽  
Spherical Particles ◽  
Dust Particles ◽  
Laboratory Measurements ◽  
Scattering Function ◽  
Hene Laser ◽  
Set Up ◽  
Good Agreement

AbstractWe have set up an experimental device to optically study the scattering properties of dust particles. Measurements over the 8 — 174° interval of scattering angles are performed on a continuously flowing dust loaded jet illuminated by a polarized red HeNe laser beam. The scattering is averaged over the population of the dust particles in the jet, which can be determined independently, and give the “volume scattering function” for the two directions of polarization directly. While results for spherical particles are in good agreement with Mie theory, those for arbitrary particles show conspicuous deviations.

scholarly journals III. On the nature and construction of the sun and fixed stars

1795 ◽  
Vol 85 ◽  
pp. 46-72 ◽  
Keyword(s):  
Central Body ◽  
Planetary System ◽  
Considerable Progress ◽  
The Sun ◽  
Great Satisfaction ◽  
The Earth ◽  
The World ◽  
Celestial Bodies ◽  
The Universe ◽  
Made In

Among the celestial bodies the sun is certainly the first which should attract our notice. It is a fountain of light that illuminates the world! it is the cause of that heat which main­tains the productive power of nature, and makes the earth a fit habitation for man! it is the central body of the planetary system; and what renders a knowledge of its nature still more interesting to us is, that the numberless stars which compose the universe, appear, by the strictest analogy, to be similar bodies. Their innate light is so intense, that it reaches the eye of the observer from the remotest regions of space, and forcibly claims his notice. Now, if we are convinced that an inquiry into the nature and properties of the sun is highly worthy of our notice, we may also with great satisfaction reflect on the considerable progress that has already been made in our knowledge of this eminent body. It would require a long detail to enumerate all the various discoveries which have been made on this subject; I shall, therefore, content myself with giving only the most capital of them.

Majolica in the Early Colonial Andes: The Role of Panamanian Wares

2001 ◽  
Vol 12 (1) ◽  
pp. 45-58 ◽  
Author(s):  
Ross W. Jamieson
Keyword(s):  
Spanish Colonial ◽  
Important Indicator ◽  
The Andes ◽  
Early Colonial ◽  
The Pacific ◽  
Elite Status ◽  
Set Up ◽  
The City ◽  
Made In

As one of the most common artifact categories found on Spanish colonial sites, the wheel-made, tin-glazed pottery known as majolica is an important chronological and social indicator for archaeologists. Initially imported from Europe, several manufacturing centers for majolica were set up in the New World by the late sixteenth century. The study of colonial majolica in the Viceroyalty of Peru, which encompassed much of South America, has received less attention than ceramic production and trade in the colonial Caribbean and Mesoamerica. Prior to 1650 the Viceroyalty of Peru was supplied with majolica largely produced in the city of Panama Vieja, on the Pacific. Panama Vieja majolica has been recovered from throughout the Andes, as far south as Argentina. Majolica made in Panama Vieja provides an important chronological indicator of early colonial archaeological contexts in the region. The reproduction of Iberian-style majolica for use on elite tables was symbolically important to the imposition of Spanish rule, and thus Panamanian majolicas also provide an important indicator of elite status on Andean colonial sites.

scholarly journals INQUIRY INTO VERTICAL MOVEMENTS OF THE EARTH‘S CRUST BASED ON SAMPLES FROM EASTERN LITHUANIA

2014 ◽  
Vol 40 (2) ◽  
pp. 58-67
Author(s):  
Ruta Puziene ◽  
Asta Anikeniene ◽  
Gitana Karsokiene
Keyword(s):  
Regression Models ◽  
Earth’S Crust ◽  
Movement Velocity ◽  
Correlation Matrices ◽  
Vertical Movements ◽  
Statistical Correlations ◽  
Horizontal Gradients ◽  
The Earth ◽  
Earth's Crust ◽  
Made In

In the research of vertical movements of the earth’s crust, examination of statistical correlations between the measured vertical movements of the earth’s crust and territorial geo-indexes is accomplished with the help of mathematical statistical analysis. Availability of the precise repeated levelling measuring data coupled with the preferred research methodology offer a chance to determine and predict recent vertical movements of the earth’s crust. For the inquiry into recent vertical movements of the earth’s crust, a Lithuanian class I vertical network levelling polygon was used. Drawing on measurements made in the polygon, vertical velocities of earth’s crust movements were calculated along the following levelling lines. For determining the relations shared by vertical movements of the earth’s crust and territorial geo-parameters, the following territory-defining parameters are accepted. Examination of the special qualities of relations shared by vertical movements of the earth’s crust and geo-parameters in the territory under research contributed to the computation of correlation matrices. Regression models are worked out taking into consideration only particular territory-defining geo-parameters, i.e. only those parameters which exhibit the following correlation coefficient value of the vertical earth’s crust movement velocity: r ≥ 0.50. A forecast of the velocities pertaining to vertical movements of the earth’s crust in the territory under examination was made with the application of regression models. Further in the process of this research, a map was compiled specifying the velocities of vertical movements of the earth’s crust in the territory. In the eastern part of this territory, the earth’s crust rises at a rate of up to 3 mm/year; while in the western part of it, the earth crust lowers at a rate of up to –1.5 mm/year. In order to pinpoint territories characterised by temperate and regular rising/lowering or intensive rising/lowering, a map of horizontal gradients of recent vertical earth crust movements in the territory enclosed by levelling polygon was compiled.

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