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The description of instruments, apparatus and methods of registration of geophysical fields and signals is given. Examples of recordings of seismic noise, seismoacoustic emission and accompanying emission processes of electromagnetic radiation, as well as seismic impulses are given. Some data on the slopes of the Dakhshur pyramid and the state of gas samples from the chambers of the Khufu (Giza) and Red (Dakhshur) pyramids are presented.
1. Preliminary remarks
In accordance with the main objectives of the study - geophysical fields and signals of the most notable Egyptian pyramids and geological structures immediately adjacent to them - initially, field work was of a prospecting reconnaissance nature and was limited to the field of pyramids near Memphis.
Even within the framework of routine geophysics, this region is of significant interest: after strong earthquakes in the early Middle Ages and a long lull, seismic activation is currently taking place. Moreover, the field of the pyramids, like the great Cairo, found themselves in a zone of increased scale and active faults. Accordingly, the initial stage of the study touched the field of the pyramids of the Giza plateau, actually bordering on greater Cairo and the farthest from the sources of man-made interference, the pyramid field in Dakhshur, as well as the pyramid in Medum [1-4].
The most complete cycle of seismic studies was carried out on the Sneferu pyramid (South). At the same time, considerable attention was paid to the study of nonlinear seismic effects and noise, which require special equipment and a high culture of conducting a seismic experiment. The apparatus and methodological foundations of such studies require a detailed special presentation, so the reader can use the final work [3-7]. During all measurements, wind and man-made noise were absent; other details are noted in the description of each specific experiment.
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2. Applied equipment and devices
The following measuring equipment was used to measure various geophysical fields of the pyramids and adjacent structures.
1. Standard seismic receivers - velocimeters of the type SV10, SG10, with a bandwidth from 10 to 1000 Hz, with a conversion factor of 16V / m / s and a non-standard high-sensitivity seismic receiver (NVS), which is a velocimeter with a high conversion factor of 500 V / m / s and a recording bandwidth of 5 to 1000Hz.
2. System of registration of analog signals IDL-02-04 (8 channels, dynamic range - 70 dB, frequency band Df = 0-25 kHz, volume of solid-state memory 4 Mbit).
3. The electronic unit of the seismic emission envelope registration system (ROSE) consisting of a microprocessor, a two-channel recorder of a digital converter of analog signals in the frequency range from 5 to 1000 Hz with subsequent summation and obtaining an average value for a selected time interval (s, min). The minimum measured signal is <10-6V (for displacements of 1011-10-12 m, for a seismic receiver - an NVS velocimeter), dynamic range ~ 120 dB, registration time 1 s.
4. Registration system IDL-02-04 for recording high-frequency signals (active seismic).
5. Dosimeter-radiometer (type ANRI-01-02) with the following technical characteristics: measurement range of gamma radiation power, mR / h - 0.010-9.999, range of gamma radiation energy, MeV - 0.06-1.25, relative error for Cs137 not over 30%.
6. Non-standard inclinometer (NN), sensitivity less than 1 arcsec (10 (9th degree) rad).
7. VHF ferrite antenna for recording electromagnetic radiation (EMP) accompanying seismoacoustic emission (SAE).
3. Methods and techniques
The main objects of measurement were seismic processes and fields and seismoacoustic emissions. For registration of seismic signals and fields, such as seismic or seismic acoustic emission and background noise, we used the NVS. The recording of seismic fields was carried out by the electronic unit of the seismic emission envelope recording system (ROSE). Amplitude and energy spectra of seismic noise recorded on the pyramid were obtained using an NVS seismic receiver.
Active seismic was limited to weak impacts (excitations) on the side faces of the pyramids or their individual blocks to determine the velocity characteristics of their materials. To determine the reflecting boundaries and assumed voids, the methods of the falling weight and standard seismic receivers - velocimeters of the SG10, SV10 types were used. At the same time, given the insignificant conversion factor of the used seismic receivers and the relatively low level of seismic noise on the pyramids, with active seismic, only seismic signals were recorded due to impacts on the pyramid array and signals associated with their reflection and propagation.
The dosimeter-radiometer ANRI-01-02 "SOSNA" was used to determine the natural radioactivity of the blocks and facing plates of the pyramids, and therefore all natural radioactive background was recorded on the day surface.
The tiltmeter was installed on the plates at the base of the pyramids, in the center of the faces on the leeward side, at a height of 2-3 m from the day surface.
4. Seismic and seismic emission fields and signals: records and preprocessing, brief comments
Seismic emission fields were recorded by the ROSE equipment on the Sneferu pyramids in Dakhshur (“Red” and “Lomanaya”) and in Medum (“Irregular”), including the inner chamber of the latter. Seismoacoustic emission (SAE) recording was mainly carried out on one channel, on the second channel, signals from the VHF antenna were simultaneously recorded. The duration of the recordings, for various reasons, ranged from 20 minutes to several (3-5) hours.
Fig. 1. Samples of recordings of seismic noise envelopes for EPS and EMP:
a) Recording of variations in the envelope of seismic emission in Dakhshur on the South "Broken" pyramid, the seismometer stood in the center of the western face at a height of 5 m from the level of the day surface; as well as recording the envelope of the signal from the ferrite antenna. Gray graph - seismic noise envelope; black - the envelope of the electromagnetic radiation of the pyramid array. The abscissa is the current time in seconds, the ordinate is the amplitude of the envelope in microvolts (March 23, 2004)
b) Recording of seismic emission envelope variations on the “Red” or Northern pyramid, in Dakhshur; The device is installed in the center of the western face near a noticeable micro-fault at a height of 4 m. The abscissa is the current time in seconds, the ordinate is the envelope amplitude in microvolts, March 18, 2004.
c) Fragment of recording Fig. 1b at the origin of coordinates from 220 to 280 s
d) Recording of variations in the seismic emission envelope on the pyramid in Medum, the device is installed in the center of the southern face (gray graph); on another channel - recording the signal envelope from the ferrite antenna (black graph), March 21, 2004
e) Recordings of seismic emission envelope variations in the pyramid chamber in Medum (gray graph) and recording of the signal envelope from the ferrite antenna (black graph), March 21, 2004.
f) Recording of envelopes of seismic noise and seismic emission variations at the top of the small pyramid near Lomanaya or Yuzhnaya in Dakhshur using two channels: with a standard lower frequency seismic receiver (fn ~ 2-5 Hz) CB5, black graph, and non-standard, more highly sensitive (5-7 times), gray graph. March 23, 2004.
g) Fragment of noise recording (Fig. 1, f); the initial section (~ 250 s) with an increased amplitude due to the occurrence of induced seismic emission.
5. Experiments on registration of seismic emission at the Broken (South) pyramid
Seismic emissions were investigated using a small pyramid. Immediately before turning on the equipment, 3 impacts were made at the base of the small pyramid to initiate seismic emission in the near-surface structures. The effect was observed for 600 s (Fig. 1f, g).
It should also be noted that the seismic noise level at the top of the small pyramid increases (by about an order of magnitude) in relation to the noise level at the base (for comparison, Figs. 1a, f), that is, the focusing effect. Seismic noise recordings were also carried out with a highly sensitive seismic receiver at the foot of the southern side of the "Broken" pyramid.
6. Active seismic fields and signals
By active seismic fields we mean shock excitation of seismic waves in a medium to determine seismic velocities and distances to geological or structural boundaries as a result of reflections of seismic waves from them. Simultaneously, the shock excitation of seismic impulses makes it possible to search for various voids and resonances, structures and objects inside the pyramid array with a rough estimate of their certain geometric dimensions. The easiest way to determine the size of the blocks that make up the surface structure of the faces or inner chambers. Seismic velocities in pyramid blocks were preliminary determined: the velocity of P-waves in limestone blocks is of the order of 2000-2500 m / s, the velocity of S-waves is 1300 m / s (according to the US expedition, these numbers are much higher), in granites the velocity of P-waves is of the order of 4500 m / s, S-waves 2500 m / s.
When hitting the blocks of the pyramid faces, not only reflections from the boundaries of the blocks determined by the geometry arise, but also various reverberations, possibly depending on the blocking of the blocks. In Dakhshur, blows were made on the blocks of the pyramid faces: two vertical (top down, bottom up) and horizontal, while the SG10 geophones were fixed vertically. Figure 2 shows live recordings of these beats.
Fig. 2. Examples of recordings of sounding strikes:
On March 19, in Dakhshur, on the "Pink" (Northern) pyramid, one vertical strike from top to bottom was made, the record of which also had some peculiarities, Fig.
In Medum on March 20, a blow was made inside the pyramid directed from top to bottom, Fig. 2f.
At the same time, in some cases, during impacts, quasi-harmonic reverberations were also observed that did not correspond to a solid array of blocks: for example, when impacting the northeastern corner of the pyramid in Medum, Fig. 2g.
On March 22, in Giza, near the Menkaur (Mikerin) pyramid, at the top of the small extreme pyramid, a shock to the ground near its base was recorded and its autocorrelation function was obtained.
In accordance with the practice of seismic data processing, the interpretation of some peaks in the shock record and its autocorrelation function testify in favor of recording a pyramid-focused seismic reflection from deep layers (~ 1 km).
There were also vertical and horizontal strikes on the southern face of the Menkaur pyramid on March 22, 2004 (Fig. 2h, i).
The observed frequencies at 241 and 231 Hz from vertical and horizontal shocks, respectively, are probably related to the conditions of excitation of oscillations in the blocks and, possibly, to the geometry of the pyramid. In the future, it is necessary to evaluate the values of the excited frequencies in the pyramids during vertical and horizontal impacts and their dependence on geometry (angle of inclination of the face and blocks, overall dimensions, height).
7. Electromagnetic fields
The connection with seismoacoustic emission of electromagnetic radiation (EMP, radio emission) on the pyramids was checked using a ferrite antenna in the kilohertz and megahertz frequency ranges. For a qualitative assessment, the equipment for recording the envelope of seismic emission (second channel) was initially used. Registration was carried out at the limit of sensitivity. No direct correlation was observed between the envelopes of seismic emission and radio emission. Therefore, averaging was carried out over a minute interval; as a result, a significant (P = 0.99) correlation was found. In the studies of the SAE and EMP, a short-wave radio receiver was also used, the work with which showed a significant decrease in the signal at medium waves and its complete absence on short ones inside the array of pyramids. This indicates electromagnetic shielding of the radio signal.
8. Variations of the slopes of the pyramids
Measurements were made of variations in slopes along one of the components of the pyramid base. The device was installed at 3-4 blocks from the level of the day surface, the North-South component was measured. Due to the significant difficulties in adjusting the device and setting it in the working range, the duration of records suitable for processing did not exceed two hours.
On March 21st, slopes (in relative units) were measured at Medum on the South side of the irregular pyramid. On 23 March, slopes were also observed in Dahshur on the South side of the "Broken" pyramid.
9. Background radiation and fluids
Radiation measurements were carried out outside and inside all the pyramids under study. Basically, a standard gamma background was revealed for limestone and basalts (about 6-9 μR / h), as well as for granites and granitoids (20-25 μR / h). However, inside the pyramid of Khufu (Cheops), in the southeastern corner of the pharaoh's chamber, on a relatively fresh cleavage, 35-37 μR / h was found. Perhaps this difference should be involved in dating the construction of the pyramid, since more thoron, which has a short half-life in the thorium series (Tn = 55.3 s, ThC` = 60.5 min, ThC “= 3.1 min), is carried to a fresher surface, which at the final stage turns into lead. The fresh chip was devoid of this lead shield in comparison with the rest of the chamber. Another fact is also recorded: the inner part of the pyramid in Medum is made of more radioactive limestone (13-15 μR / h),than external (5-7 μR / h). It is possible that limestone from different places was used to build the pyramid. Searching for and locating the mining site for more radioactive limestone can provide additional data for the construction of the inner part of the pyramid. But another explanation is also possible.
Usually inside the pyramids in chambers made of limestone, the radioactive background decreased by 2 times and amounted to 2 to 5 μR / h, this feature can be used when registering high-energy cosmic rays inside the pyramids.
10. Analysis of gas samples
Gas samples were taken from the chamber of the pharaoh of the Khufu pyramid and from one of the chambers of the "Red" pyramid in Dakhshur. The analysis was carried out on the basis of the existence of 40 components. The composition of the atmosphere of the chamber of the pyramid of Khufu (Cheops) does not differ from the standard; and for the "Red" (Northern) pyramid there are anomalies, since the total content of C8-C12 hydrocarbons reaches 9mg / m3.
conclusions
No unique instrumentation is required to study geophysical fields and signals.
The waveform of seismic impulses indicates the existence of internal high-frequency resonances in some pyramids. All large pyramids and adjacent structures are characterized by the existence of seismoacoustic emission. Seismoacoustic emission is accompanied by electromagnetic radiation.
Literature
Zamarovsky V. Their Majesties are pyramids. Moscow: Nauka, 1986. S. 430.
Kink H. A. How the Egyptian pyramids were built. M., 1967.
Elebrant P. The Tragedies of the Pyramids. 500 years of plundering of Egyptian tombs. M., 1984.
Silliotty A. The Pyramids. Egypt Pocket Guide. The American University in Cairo Press. 2003
Khavroshkin O. B. Some problems of nonlinear seismology. Moscow: OIFZ RAN, 1999. S. 286.
Khavroshkin OB, Tsyplakov VV Nonlinear seismology: Experimental structure // Nonlinear acoustics at the beginning of the 21th century / Ed. Oleg V. Rudenko, Oleg A. Sapozhnikov. 16th Vol. 1. M., 2002.622 p.
Khavroshkin, O. B. and Tsyplakov, V. V., Hardware and methodological foundations of experimental nonlinear seismology, Seismicheskie pribory. Moscow: OFZ RAS, 2003. Issue. 39. S. 43-71.
Authors: PAVLOV D. G., KHAVROSHKIN O. B., TSYPLAKOV V. V.
