Seismometer - Knowledge

1165: 1334:(essentially a sound wave in rock) can be determined by sending packets in both directions in the looped pair of optical fibers; the difference in the arrival times of the first pair of perturbed packets indicates the distance along the cable. This point is also the point closest to the earthquake's epicenter, which should be on a plane perpendicular to the cable. The difference between the p-wave/s-wave arrival times provides a distance (under ideal conditions), constraining the epicenter to a circle. A second detection on a non-parallel cable is needed to resolve the ambiguity of the resulting solution. Additional observations constrain the location of the earthquake's epicenter, and may resolve the depth. 936:

seconds, or once per thirty seconds. The general-purpose instruments of small stations or amateurs usually oscillate once per ten seconds. A pan of oil is placed under the arm, and a small sheet of metal mounted on the underside of the arm drags in the oil to damp oscillations. The level of oil, position on the arm, and angle and size of sheet is adjusted until the damping is "critical", that is, almost having oscillation. The hinge is very low friction, often torsion wires, so the only friction is the internal friction of the wire. Small seismographs with low proof masses are placed in a vacuum to reduce disturbances from air currents.

1368: 474:. The best mountings may be in deep boreholes, which avoid thermal effects, ground noise and tilting from weather and tides. Other instruments are often mounted in insulated enclosures on small buried piers of unreinforced concrete. Reinforcing rods and aggregates would distort the pier as the temperature changes. A site is always surveyed for ground noise with a temporary installation before pouring the pier and laying conduit. Originally, European seismographs were placed in a particular area after a destructive earthquake. Today, they are spread to provide appropriate coverage (in the case of 959: 967: 834: 48: 1360: 1169: 1009:/m; local geologic seismographs, about 1,500 V/m; and teleseismographs, used for world survey, about 20,000 V/m. Instruments come in three main varieties: short period, long period and broadband. The short and long period measure velocity and are very sensitive, however they 'clip' the signal or go off-scale for ground motion that is strong enough to be felt by people. A 24-bit analog-to-digital conversion channel is commonplace. Practical devices are linear to roughly one part per million. 1167: 943:

systems, the light was reflected to a pair of differential electronic photosensors called a photomultiplier. The voltage generated in the photomultiplier was used to drive galvanometers which had a small mirror mounted on the axis. The moving reflected light beam would strike the surface of the turning drum, which was covered with photo-sensitive paper. The expense of developing photo-sensitive paper caused many seismic observatories to switch to ink or thermal-sensitive paper.

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that record data from up to 20 channels into a 16-mm film. The recorded film can be viewed by a machine. The reading and measuring from these types of media can be done by hand. After the digital processing has been used, the archives of the seismic data were recorded in magnetic tapes. Due to the deterioration of older magnetic tape medias, large number of waveforms from the archives are not recoverable.

663:, says that it was a large bronze vessel, about 2 meters in diameter; at eight points around the top were dragon's heads holding bronze balls. When there was an earthquake, one of the dragons' mouths would open and drop its ball into a bronze toad at the base, making a sound and supposedly showing the direction of the earthquake. On at least one occasion, probably at the time of a large earthquake in 420: 1275:

geophones are sometimes used to perform three-dimensional reflective imaging of subsurface features. Basic linear refractive geomapping software (once a black art) is available off-the-shelf, running on laptop computers, using strings as small as three geophones. Some systems now come in an 18" (0.5 m) plastic field case with a computer, display and printer in the cover.

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recording system allowed for a continuous record, the first to do so. The first seismogram was recorded on 3 November 1880 on both of Ewing's instruments. Modern seismometers would eventually descend from these designs. Milne has been referred to as the 'Father of modern seismology' and his seismograph design has been called the first modern seismometer.

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sensitive instruments to ten seconds. The basic damped horizontal pendulum seismometer swings like the gate of a fence. A heavy weight is mounted on the point of a long (from 10 cm to several meters) triangle, hinged at its vertical edge. As the ground moves, the weight stays unmoving, swinging the "gate" on the hinge.

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unrolled behind a truck. Now most short-range systems use "thumpers" that hit the ground, and some small commercial systems have such good digital signal processing that a few sledgehammer strikes provide enough signal for short-distance refractive surveys. Exotic cross or two-dimensional arrays of

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One of the continuing problems with sensitive vertical seismographs is the buoyancy of their masses. The uneven changes in pressure caused by wind blowing on an open window can easily change the density of the air in a room enough to cause a vertical seismograph to show spurious signals. Therefore,

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Later, professional suites of instruments for the worldwide standard seismographic network had one set of instruments tuned to oscillate at fifteen seconds, and the other at ninety seconds, each set measuring in three directions. Amateurs or observatories with limited means tuned their smaller, less

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The first seismographs were invented in the 1870s and 1880s. The first seismograph was produced by Filippo Cecchi in around 1875. A seismoscope would trigger the device to begin recording, and then a recording surface would produce a graphical illustration of the tremors automatically (a seismogram).

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in AD 143, the seismoscope indicated an earthquake even though one was not felt. The available text says that inside the vessel was a central column that could move along eight tracks; this is thought to refer to a pendulum, though it is not known exactly how this was linked to a mechanism that would

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Most instruments measure directly the ground motion using the distance sensor. The voltage generated in a sense coil on the mass by the magnet directly measures the instantaneous velocity of the ground. The current to the drive coil provides a sensitive, accurate measurement of the force between the

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expressed their dissatisfaction with the current available seismometers, still using the large 1842 Forbes device located in Comrie Parish Church, and requested a seismometer which was compact, easy to install and easy to read. In 1875 they settled on a large example of the Mallet device, consisting

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Prior to the availability of digital processing of seismic data in the late 1970s, the records were done in a few different forms on different types of media. A "Helicorder" drum was a device used to record data into photographic paper or in the form of paper and ink. A "Develocorder" was a machine

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Modern instruments use electronic sensors, amplifiers, and recording devices. Most are broadband covering a wide range of frequencies. Some seismometers can measure motions with frequencies from 500 Hz to 0.00118 Hz (1/500 = 0.002 seconds per cycle, to 1/0.00118 = 850 seconds per cycle).

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The advantage of a horizontal pendulum is that it achieves very low frequencies of oscillation in a compact instrument. The "gate" is slightly tilted, so the weight tends to slowly return to a central position. The pendulum is adjusted (before the damping is installed) to oscillate once per three

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Both accessed 2010-9-29 Morrissey was a professional seismographic instrument engineer. This superior design uses a zero-length spring to achieve a 60-second period, active feedback and a uniquely convenient variable reluctance differential transducer, with parts scavenged from a hardware store.

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Marra, Giuseppe; Clivati, Cecilia; Luckett, Richard; Tampellini, Anna; Kronjäger, Jochen; Wright, Louise; Mura, Alberto; Levi, Filippo; Robinson, Stephen; Xuereb, André; Baptie, Brian; Calonico, Davide (3 August 2016), "Ultrastable laser interferometry for earthquake detection with terrestrial and

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of various sizes installed at right angles to each other on a sand bed, where larger earthquakes would knock down larger pins. This device was constructed in 'Earthquake House' near Comrie, which can be considered the world's first purpose-built seismological observatory. As of 2013, no earthquake

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as wave sources. The first efforts at this method used manual data reduction from paper seismograph charts. Modern digital seismograph records are better adapted to direct computer use. With inexpensive seismometer designs and internet access, amateurs and small institutions have even formed a

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Delivered seismometers come with two styles of output: analog and digital. Analog seismographs require analog recording equipment, possibly including an analog-to-digital converter. The output of a digital seismograph can be simply input to a computer. It presents the data in a standard digital

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Early seismometers had an arrangement of levers on jeweled bearings, to scratch smoked glass or paper. Later, mirrors reflected a light beam to a direct-recording plate or roll of photographic paper. Briefly, some designs returned to mechanical movements to save money. In mid-twentieth-century

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published an 1848 paper where he suggested ideas for seismometer design, suggesting that such a device would need to register time, record amplitudes horizontally and vertically, and ascertain direction. His suggested design was funded, and construction was attempted, but his final design did not

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in 1796, who improved upon Salsano's pendulum instrument, using a pencil to mark, and using a hair attached to the mechanism to inhibit the motion of a clock's balance wheel. This meant that the clock would only start once an earthquake took place, allowing determination of the time of incidence.

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in response to an Earthquake that took place on February 22, 1880, at Yokohama (Yokohama earthquake). Two instruments were constructed by Ewing over the next year, one being a common-pendulum seismometer and the other being the first seismometer using a damped horizontal pendulum. The innovative

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are often heavy cylindrical magnets with a spring-mounted coil inside. As the case moves, the coil tends to stay stationary, so the magnetic field cuts the wires, inducing current in the output wires. They receive frequencies from several hundred hertz down to 1 Hz. Some have electronic

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Today, the most common recorder is a computer with an analog-to-digital converter, a disk drive and an internet connection; for amateurs, a PC with a sound card and associated software is adequate. Most systems record continuously, but some record only when a signal is detected, as shown by a

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It might seem logical to make the heavy magnet serve as a mass, but that subjects the seismograph to errors when the Earth's magnetic field moves. This is also why seismograph's moving parts are constructed from a material that interacts minimally with magnetic fields. A seismograph is also

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A simple seismometer, sensitive to up-down motions of the Earth, is like a weight hanging from a spring, both suspended from a frame that moves along with any motion detected. The relative motion between the weight (called the mass) and the frame provides a measurement of the vertical

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Early seismometers used optical levers or mechanical linkages to amplify the small motions involved, recording on soot-covered paper or photographic paper. Modern instruments use electronics. In some systems, the mass is held nearly motionless relative to the frame by an electronic

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further developed this concept in 1751, having the pendulum create trace marks in sand under the mechanism, providing both magnitude and direction of motion. Neapolitan clockmaker Domenico Salsano produced a similar pendulum which recorded using a paintbrush in 1783, labelling it a

1323:-scale changes in the length of the cable. As the length changes so does the time it takes a packet of light to traverse to the far end of the cable and back (using a second fiber). Using ultra-stable metrology-grade lasers, these extremely minute shifts of timing (on the order of 532:, though it is more applicable to the older instruments in which the measuring and recording of ground motion were combined, than to modern systems, in which these functions are separated. Both types provide a continuous record of ground motion; this record distinguishes them from 684:

described a seismoscope in 1703, which used a bowl filled with mercury which would spill into one of eight receivers equally spaced around the bowl, though there is no evidence that he actually constructed the device. A mercury seismoscope was constructed in 1784 or 1785 by

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Seismic observatories usually have instruments measuring three axes: north-south (y-axis), east-west (x-axis), and vertical (z-axis). If only one axis is measured, it is usually the vertical because it is less noisy and gives better records of some seismic waves.

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of a seismograph must be accurately characterized, so that its frequency response is known. This is often the crucial difference between professional and amateur instruments. Most are characterized on a variable frequency shaking table.

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In other systems the weight is allowed to move, and its motion produces an electrical charge in a coil attached to the mass which voltage moves through the magnetic field of a magnet attached to the frame. This design is often used in a

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in 1842, which recorded the measurements of seismic activity through the use of a pencil placed on paper above the pendulum. The designs provided did not prove effective, according to Milne's reports. It was Milne who coined the word

920:). While not sensitive enough to detect distant earthquakes, this instrument could indicate the direction of the pressure waves and thus help find the epicenter of a local quake. Such instruments were useful in the analysis of the 1350:

algorithm called UrbanDenoiser which can detect earthquakes, particularly in urban cities. The algorithm filters out the background noise from the seismic noise gathered from busy cities in urban areas to detect earthquakes.

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This technique is expected to be a boon in observing earthquakes, especially the smaller ones, in vast portions of the global ocean where there are no seismometers, and at a cost much cheaper than ocean bottom seismometers.

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between 1848 and 1850, which used a point-suspended rigid cylindrical pendulum covered in paper, drawn upon by a fixed pencil. The cylinder was rotated every 24 hours, providing an approximate time for a given quake.

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most professional seismographs are sealed in rigid gas-tight enclosures. For example, this is why a common Streckeisen model has a thick glass base that must be glued to its pier without bubbles in the glue.

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in 1841, to describe this instrument. In 1843, the first horizontal pendulum was used in a seismometer, reported by Milne (though it is unclear if he was the original inventor). After these inventions,

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This produced the first effective measurement of horizontal motion. Gray would produce the first reliable method for recording vertical motion, which produced the first effective 3-axis recordings.

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The hinges on a seismograph are usually patented, and by the time the patent has expired, the design has been improved. The most successful public domain designs use thin foil hinges in a clamp.

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later to give velocity and position. Strong-motion seismometers are not as sensitive to ground motions as teleseismic instruments but they stay on scale during the strongest seismic shaking.

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set up a network of pendulum earthquake detectors following the 1731 Puglia Earthquake, where the amplitude was detected using a protractor to measure the swinging motion. Benedictine monk

1033:(cover removed). Two masses for x- and y-direction can be seen, the third one for z-direction is below. This model is a CMG-40TOBS, manufactured by Güralp Systems Ltd and is part of the 740:

to detect the direction of an earthquake, where the lead fell into four bins arranged in a circle, to determine the quadrant of earthquake incidence. He completed the instrument in 1841.

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invented a precursor of seismometer, a vertical wooden poles connected with wooden gutters on the central axis functioned to fill water into a vessel until full to detect earthquakes.

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The concept of measuring the "shaking" of something means that the word "seismograph" might be used in a more general sense. For example, a monitoring station that tracks changes in

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applies a magnetic or electrostatic force to keep the mass nearly motionless. The voltage needed to produce this force is the output of the seismometer, which is recorded digitally.

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short-term increase in the variation of the signal, compared to its long-term average (which can vary slowly because of changes in seismic noise), also known as a STA/LTA trigger.

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open only one dragon's mouth. The first earthquake recorded by this seismoscope was supposedly "somewhere in the east". Days later, a rider from the east reported this earthquake.

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The mechanical suspension for horizontal instruments remains the garden-gate described above. Vertical instruments use some kind of constant-force suspension, such as the

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Seismometers unavoidably introduce some distortion into the signals they measure, but professionally designed systems have carefully characterized frequency transforms.

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Oldroyd, David; Amador, F.; Kozák, Jan; Carneiro, Ana; Pinto, Manuel (2007-01-01). "The Study of Earthquakes in the Hundred Years Following Lisbon Earthquake of 1755".

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experiments in England observed noise with a wave-form resembling the seismic waves generated by earthquakes. This was found to match seismological observations of an

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A worldwide array of seismometers can actually image the interior of the Earth in wave-speed and transmissivity. This type of system uses events such as earthquakes,

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Small seismic imaging systems are now sufficiently inexpensive to be used by civil engineers to survey foundation sites, locate bedrock, and find subsurface water.

475: 1994: 680:(founded 1259) in Persia, though it is unclear whether these were constructed independently or based on the first seismoscope. French physicist and priest 924:. Further analysis was performed in the 1980s, using these early recordings, enabling a more precise determination of the initial fault break location in 1502: 686: 1185:

Strain-beam accelerometers constructed as integrated circuits are too insensitive for geologic seismographs (2002), but are widely used in geophones.

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In most designs the electronics holds a mass motionless relative to the frame. This device is called a "force balance accelerometer". It measures

912:. The result is that the stylus scratched a pattern corresponding with the Earth's movement. This type of strong-motion seismometer recorded upon a 1525: 2390:

The frequency transform is carefully designed, unlike most amateur instruments. Morrisey is deceased, but the site remains up as a public service.

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instead of velocity of ground movement. Basically, the distance between the mass and some part of the frame is measured very precisely, by a

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with vibration, which then powered an electromagnet to stop a clock. Palmieri seismometers were widely distributed and used for a long time.

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systems. These seismometers are often used as part of a large scale governmental or scientific project, but some organizations such as the

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Zollner described torsionally suspended horizontal pendulums as early as 1869, but developed them for gravimetry rather than seismometry.

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in order to produce better detection devices for earthquakes. The outcome of this was an inverted pendulum seismometer constructed by

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In the Southern Sung dynasty, gift money for bestowing upon officials by the imperial court was wrapped in paper envelopes (chih pao)

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Basic horizontal-motion seismograph. The inertia of the round weight tends to hold the pen still while the base moves back and forth.

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However, the instrument was not sensitive enough, and the first seismogram produced by the instrument was in 1887, by which time

659:(translated as, "instrument for measuring the seasonal winds and the movements of the Earth"). The description we have, from the 582:, a Chinese mathematician and astronomer. The first Western description of the device comes from the French physicist and priest 2127: 838: 1303:

6.0 earthquake in Italy, ~1400 km away. Further experiments in England, Italy, and with a submarine fiber optic cable to

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Ferrari, Graziano (1997-01-01). "Cultural and scientific value of seismology's heritage in Europe: why and how to preserve".

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fulfill his expectations and suffered from the same problems as the Forbes design, being inaccurate and not self-recording.

1904: 717:. Naturalist Nicolo Zupo devised an instrument to detect electrical disturbances and earthquakes at the same time (1784). 689:, a copy of which can be found at the University Library in Bologna, and a further mercury seismoscope was constructed by 393:. The output of such a device—formerly recorded on paper (see picture) or film, now recorded and processed digitally—is a 1095:

sensitive to changes in temperature so many instruments are constructed from low expansion materials such as nonmagnetic

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Seismometer without housing; presented during a demonstration for children about earthquakes at Alfred Wegener Institute.

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Seismographic systems used for petroleum or other mineral exploration historically used an explosive and a wireline of

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mass and frame, thus measuring directly the ground's acceleration (using f=ma where f=force, m=mass, a=acceleration).

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had completely spilled over, and did not provide useful information. He therefore devised a portable device that used

432:. A rotating drum is attached to the frame and a pen is attached to the weight, thus recording any ground motion in a 1433: 1122:. The data from such an instrument is essential to understand how an earthquake affects man-made structures, through 1208:

can also be used to precisely locate, in three dimensions, the source of an earthquake, using the time it takes for

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also built a seismological tool of unknown design or efficacy (known as an earthquake machine) in the late 1790s.

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Some other sensitive designs measure the current generated by the flow of a non-corrosive ionic fluid through an

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damping, a low-budget way to get some of the performance of the closed-loop wide-band geologic seismographs.

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Earthquake Locations Determined by the Southern Alaska Seismograph Network for October 1971 through May 1989

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After World War II, the seismometers developed by Milne, Ewing and Gray were adapted into the widely used

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is a free tool for recent Macintosh laptop computers that implements a real-time three-axis seismograph.

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has been large enough to cause any of the cylinders to fall in either the original device or replicas.

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Science and Civilization in China, Volume 3: Mathematics and the Sciences of the Heavens and the Earth

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The foundation of a seismic station is critical. A professional station is sometimes mounted on

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The first moderately successful device for detecting the time of an earthquake was devised by

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discusses the history of development of the primary technology in global earthquake research.

1443: 1244: 1237: 318: 246: 119: 99: 94: 89: 2028:. In Beer, Michael; Kougioumtzoglou, Ioannis A.; Patelli, Edoardo; Siu-Kui Au, Ivan (eds.). 690: 2239: 2228:"Toward improved urban earthquake monitoring through deep-learning-based noise suppression" 1950: 1858: 1793: 1079:. One of the amplified currents from the negative feedback loop drives a coil very like a 1072: 958: 681: 677: 655:

is said to have invented the first seismoscope (by the definition above), which was called

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Fogleman, Kent A.; Lahr, John C.; Stephens, Christopher D.; Page, Robert A. (June 1993).

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Any movement from the ground moves the frame. The mass tends not to move because of its

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Sleeswyk AW, Sivin N (1983). "Dragons and toads: the Chinese seismoscope of BC. 132".

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William H.K. Lee; Paul Jennings; Carl Kisslinger; Hiroo Kanamori (27 September 2002).

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The Development Of Very-Broad-Band Seismography: Quanterra And The Iris Collaboration

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lander, the first time a seismometer was placed onto the surface of another planet.

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The first seismometer was made in China during the 2nd century. It was invented by

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Seismometers, seismographs, seismograms – what's the difference? How do they work?

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Yang, Lei; Liu, Xin; Zhu, Weiqiang; Zhao, Liang; Beroza, Gregory C. (2022-04-15).

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in Japan, from 1880 to 1895. Milne, Ewing and Gray, all having been hired by the

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In 1880, the first horizontal pendulum seismometer was developed by the team of

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A strong-motion seismometer measures acceleration. This can be mathematically

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to provide a long period (high sensitivity). Some modern instruments use a

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detected additional earthquakes, including one 4,100 km away, and an

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circuit. The amount of force necessary to achieve this is then recorded.

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Pendulum devices were developing at the same time. Neapolitan naturalist

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Another type of seismometer is a digital strong-motion seismometer, or

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Historical Encyclopedia of Natural and Mathematical Sciences, Volume 1

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An early special-purpose seismometer consisted of a large, stationary

2426: 1813:"The invention of the Seismoscope | The Asian Age Online, Bangladesh" 1375: 1291: 1042: 1025: 974: 737: 611: 589:

Seismometers were placed on the Moon starting in 1969 as part of the

451:. The motion of the mass relative to the frame is measured, and the 386: 175: 69: 64: 2128:"A Biography of Lucien LaCoste, inventor of the zero-length spring" 1413: 1271: 1189: 1178: 1138: 1076: 1050: 1014: 1002: 893: 753: 586:

in 1703. The modern seismometer was developed in the 19th century.

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that responds to ground displacement and shaking such as caused by

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The modern broadband seismograph can record a very broad range of

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in 1841, to describe an instrument designed by Scottish physicist

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Sean Morrisey's professional design of an amateur teleseismograph

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International Handbook of Earthquake & Engineering Seismology

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International Handbook of Earthquake & Engineering Seismology

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Strong motion sensors are used for intensity meter applications.

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Instrument that records seismic waves by measuring ground motions

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A new technique for detecting earthquakes has been found, using

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Agnew, Duncan Carr (2003). "Ch. 1: History of Seismology".

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The technical discipline concerning such devices is called

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The point of the cable first disturbed by an earthquake's

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By the 13th century, seismographic devices existed in the

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Erhard Wielandt's 'Seismic Sensors and their Calibration'

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cables. In 2016 a team of metrologists running frequency

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The Lehman amateur seismograph, from Scientific American

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Shelley Unbound: Discovering Frankenstein's True Creator

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Simplified LaCoste suspension using a zero-length spring

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started to move, the heavy mass of the pendulum had the

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Science and Civilisation in China: Paper and Printing

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and its subsequent progression, mostly to the south.

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After an earthquake taking place on October 4, 1834,

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Journal of the History of the Earth Sciences Society

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Earthquakes and Engineers: an International History

743: 2317:"NEWS FLASH!! SCSN Earthquake Catalog Completed!!" 2066: 1309: 837:Milne horizontal pendulum seismometer. One of the 803:By 1872, a committee in the United Kingdom led by 2103:"Physics of the Zero-Length Spring of Geoscience" 1001:Modern sensitivities come in three broad ranges: 816: 2446: 2067:Herbert-Gustar, A. L.; Nott, Patrick A. (1980). 1762:"NASA's InSight Places First Instrument on Mars" 1760:Cook, Jia-Rui; Good, Andrew (19 December 2018). 1319:Seismic waves are detectable because they cause 1173:Seismometer in operation recording a seismogram. 1156:A Kinemetrics seismograph, formerly used by the 463:, which is used in exploration for oil and gas. 2032:. Berlin, Heidelberg: Springer. pp. 1–31. 1316:3.4 earthquake 89 km away from the cable. 399:. Such data is used to locate and characterize 2225: 1722: 1600: 1199: 732:observed that the mercury seismoscope held at 713:, possibly the first use of a similar word to 2069:John Milne : father of modern seismology 1753: 1553: 1551: 1346:Researchers at Stanford University created a 1113: 877:in the previous five years to assist Japan's 350: 1530:. Reston, VA: ASCE Press. pp. 122–125. 1519: 1517: 1515: 748:In response to a series of earthquakes near 671: 1729:. Cambridge University Press. p. 122. 1557: 2380:- not designed for calibrated measurement. 1844: 1842: 1840: 1838: 1836: 1834: 1832: 1718: 1716: 1548: 1523: 987:suspension. The LaCoste suspension uses a 498:, a shaking or quake, from the verb σείω, 357: 343: 2267: 2199: 2189: 2019: 2017: 2015: 1962: 1932: 1930: 1928: 1926: 1512: 1296: 2221: 2219: 1759: 1374: 1366: 1358: 1163: 1158:United States Department of the Interior 1151: 1062:linear variable differential transformer 1024: 973: 965: 957: 832: 610: 591:Apollo Lunar Surface Experiments Package 478:) or concentrated in high-risk regions ( 418: 18: 1883: 1829: 1810: 1787: 1781: 1713: 1694: 1692: 1591: 1192:sponge or a conductive fluid through a 826:had already demonstrated his design in 756:in 1839, a committee was formed in the 2447: 2030:Encyclopedia of Earthquake Engineering 2023: 2012: 1936: 1923: 1071:That measurement is then amplified by 1066:linear variable differential capacitor 970:CMG-40T triaxial broadband seismometer 839:Important Cultural Properties of Japan 2216: 2146:"Redwood City Public Seismic Network" 1466: 953: 843:National Museum of Nature and Science 528:, to draw. It is often used to mean 2314: 1902: 1689: 1371:Matsushiro Seismological Observatory 1035:Monterey Accelerated Research System 1871:10.17704/eshi.26.2.h9v2708334745978 1471:. Vol. Part A. pp. 3–11. 1075:attached to parts of an electronic 1020: 414: 13: 1943:Bulletin of Earthquake Engineering 1282:Fiber optic cables as seismometers 14: 2481: 2366:The history of early seismometers 2359: 1939:"A history of British seismology" 1886:Cah. Cent. Europ. Geodyn. Seismol 1613:. Academic Press. pp. 283–. 1434:Pacific Northwest Seismic Network 764:, first presented in a report by 1341: 744:Early Modern designs (1839–1880) 661:History of the Later Han Dynasty 506:, to measure, and was coined by 46: 2341: 2308: 2284: 2168: 2138: 2120: 2095: 2083:"Who Invented the Seismograph?" 2075: 2060: 2038:10.1007/978-3-642-36197-5_171-1 1987: 1937:Musson, R. M. W. (2013-06-01). 1896: 1877: 1804: 1226:International Monitoring System 993:"triaxial" or "Galperin" design 485: 2435:– How Does A Seismometer Work? 2387:Also see Keith Payea's version 1664: 1634: 1596:. San Francisco: W.H. Freeman. 1585: 1493: 1460: 1363:Viewing of a Develocorder film 1267:"public seismograph network". 1147: 883:Seismological Society of Japan 817:The first seismographs (1880-) 606: 1: 1903:Hart, Scott de (2013-07-22). 1454: 922:1906 San Francisco earthquake 785:constructed a seismometer in 2417:Hawaiian Volcano Observatory 1354: 1029:A low-frequency 3-direction 566:studies the "quakes" on the 7: 1909:. Feral House. p. 39. 1524:Reitherman, Robert (2012). 1409:Galitzine, Boris Borisovich 1397: 1327:) appear as phase-changes. 1232:explosions, as well as for 1212:to propagate away from the 1200:Interconnected seismometers 871:foreign-government advisors 808:of an array of cylindrical 520:is another Greek term from 10: 2486: 2429:– Research References 2012 2423:– retrieved on 2009-06-15. 1564:. Springer. p. 2657. 1382: 1216:, the initiating point of 1114:Strong-motion seismometers 1105:Another issue is that the 628:List of Chinese inventions 625: 573: 490:The word derives from the 255:Coordinating Committee for 2315:Hutton, Kate; Yu, Ellen. 1964:10.1007/s10518-013-9444-5 1676:solar-center.stanford.edu 1449:Wood-Anderson seismometer 1204:Seismometers spaced in a 1064:. Some instruments use a 1013:format (often "SE2" over 908:to stay still within the 672:Early designs (1259–1839) 286:Adams–Williamson equation 2026:"Historical Seismometer" 1788:Needham, Joseph (1959). 1558:Ben-Menahem, A. (2009). 1234:Earthquake early warning 1031:ocean-bottom seismometer 502:, to shake; and μέτρον, 480:strong-motion seismology 234:Seismic intensity scales 229:Seismic magnitude scales 2191:10.1126/science.aat4458 1723:Joseph Needham (1985). 948:Press-Ewing seismometer 900:on the bottom. As the 23:Kinemetric seismograph. 2470:Seismology instruments 2252:10.1126/sciadv.abl3564 2024:Batlló, Josep (2021). 1592:Richter, C.F. (1958). 1380: 1372: 1364: 1228:to detect underground 1174: 1161: 1132:engineering seismology 1124:earthquake engineering 1077:negative feedback loop 1038: 979: 971: 963: 854: 638:Amenhotep, son of Hapu 623: 476:weak-motion seismology 449:negative feedback loop 424: 296:Earthquake engineering 24: 2465:Measuring instruments 2296:MIT Technology Review 1811:Szczepanski, Kallie. 1594:Elementary Seismology 1444:Quake-Catcher Network 1383:Further information: 1378: 1370: 1362: 1245:reflection seismology 1238:Quake-Catcher Network 1172: 1155: 1073:electronic amplifiers 1028: 977: 969: 961: 881:efforts, founded the 836: 614: 422: 319:Earth Sciences Portal 291:Flinn–Engdahl regions 257:Earthquake Prediction 22: 2413:Video of seismograph 1642:"The RF Seismograph" 682:Jean de Hautefeuille 678:Maragheh observatory 584:Jean de Hautefeuille 281:Shear wave splitting 2244:2022SciA....8L3564Y 2176:submarine cables", 1955:2013BuEE...11..715M 1863:2007ESHis..26..321O 1798:1959scc3.book.....N 1222:Earthquake location 1177:Accelerographs and 916:(glass with carbon 403:, and to study the 181:Epicentral distance 2460:Chinese inventions 2455:1880 introductions 2405:2016-08-10 at the 2376:2009-02-04 at the 2134:on March 20, 2007. 2107:physics.mercer.edu 1652:on 1 December 2017 1505:2010-09-24 at the 1381: 1379:A Seismogram graph 1373: 1365: 1264:nuclear explosions 1220:rupture (See also 1175: 1162: 1039: 989:zero-length spring 980: 972: 964: 954:Modern instruments 863:James Alfred Ewing 855: 762:James David Forbes 734:Bologna University 722:Ascanio Filomarino 691:Niccolò Cacciatore 624: 558:waves presents an 512:James David Forbes 425: 405:internal structure 383:volcanic eruptions 158:Induced seismicity 105:Remotely triggered 25: 2184:(6401): 486–490, 2047:978-3-642-36197-5 1916:978-1-936239-64-1 1736:978-0-521-08690-5 1672:"The Singing Sun" 1620:978-0-08-048922-3 1571:978-3-540-68831-0 1537:978-0-7844-1071-4 1478:978-0-12-440652-0 1170: 1107:transfer function 841:. Exhibit in the 657:Houfeng Didong Yi 621:Houfeng Didong Yi 367: 366: 2477: 2354: 2353: 2345: 2339: 2338: 2336: 2334: 2328: 2321: 2312: 2306: 2305: 2303: 2302: 2288: 2282: 2281: 2271: 2238:(15): eabl3564. 2232:Science Advances 2223: 2214: 2212: 2203: 2193: 2172: 2166: 2165: 2163: 2161: 2156:on 26 March 2018 2152:. Archived from 2142: 2136: 2135: 2130:. Archived from 2124: 2118: 2117: 2115: 2113: 2099: 2093: 2092: 2090: 2089: 2079: 2073: 2072: 2064: 2058: 2057: 2055: 2054: 2021: 2010: 2009: 2007: 2006: 1997:. Archived from 1991: 1985: 1984: 1966: 1934: 1921: 1920: 1900: 1894: 1893: 1881: 1875: 1874: 1846: 1827: 1826: 1824: 1823: 1808: 1802: 1801: 1785: 1779: 1778: 1776: 1774: 1757: 1751: 1750: 1745: 1743: 1720: 1711: 1710: 1696: 1687: 1686: 1684: 1682: 1668: 1662: 1661: 1659: 1657: 1648:. Archived from 1638: 1632: 1631: 1629: 1627: 1604: 1598: 1597: 1589: 1583: 1582: 1580: 1578: 1555: 1546: 1545: 1540:. Archived from 1521: 1510: 1497: 1491: 1490: 1464: 1314: 1301: 1171: 1021:Teleseismometers 875:Meiji Government 869:, who worked as 798:electric circuit 766:David Milne-Home 687:Atanasio Cavalli 554:noise affecting 508:David Milne-Home 415:Basic principles 359: 352: 345: 130:Earthquake swarm 50: 27: 26: 2485: 2484: 2480: 2479: 2478: 2476: 2475: 2474: 2445: 2444: 2407:Wayback Machine 2378:Wayback Machine 2362: 2357: 2352:(Report). USGS. 2346: 2342: 2332: 2330: 2329:on 14 July 2014 2326: 2319: 2313: 2309: 2300: 2298: 2290: 2289: 2285: 2224: 2217: 2173: 2169: 2159: 2157: 2144: 2143: 2139: 2126: 2125: 2121: 2111: 2109: 2101: 2100: 2096: 2087: 2085: 2081: 2080: 2076: 2065: 2061: 2052: 2050: 2048: 2022: 2013: 2004: 2002: 1995:"Seismographen" 1993: 1992: 1988: 1935: 1924: 1917: 1901: 1897: 1882: 1878: 1847: 1830: 1821: 1819: 1809: 1805: 1786: 1782: 1772: 1770: 1758: 1754: 1741: 1739: 1737: 1721: 1714: 1702:Chinese Science 1697: 1690: 1680: 1678: 1670: 1669: 1665: 1655: 1653: 1640: 1639: 1635: 1625: 1623: 1621: 1605: 1601: 1590: 1586: 1576: 1574: 1572: 1556: 1549: 1538: 1522: 1513: 1507:Wayback Machine 1498: 1494: 1479: 1465: 1461: 1457: 1439:Plate tectonics 1424:IRIS Consortium 1400: 1387: 1357: 1344: 1313: 1300: 1284: 1202: 1164: 1150: 1116: 1023: 956: 819: 746: 674: 630: 619:'s seismoscope 609: 576: 564:helioseismology 552:electromagnetic 488: 417: 363: 311: 310: 276: 268: 267: 259: 256: 249: 239: 238: 219: 211: 210: 171: 170:Characteristics 163: 162: 143: 135: 134: 60: 17: 12: 11: 5: 2483: 2473: 2472: 2467: 2462: 2457: 2443: 2442: 2436: 2430: 2424: 2410: 2397: 2391: 2381: 2368: 2361: 2360:External links 2358: 2356: 2355: 2340: 2307: 2283: 2215: 2167: 2137: 2119: 2094: 2074: 2059: 2046: 2011: 1986: 1949:(3): 715–861. 1922: 1915: 1895: 1876: 1857:(2): 321–370. 1828: 1803: 1780: 1752: 1735: 1712: 1688: 1663: 1633: 1619: 1599: 1584: 1570: 1547: 1544:on 2012-07-26. 1536: 1511: 1492: 1477: 1458: 1456: 1453: 1452: 1451: 1446: 1441: 1436: 1431: 1426: 1421: 1416: 1411: 1406: 1399: 1396: 1356: 1353: 1343: 1340: 1311: 1298: 1283: 1280: 1201: 1198: 1194:magnetic field 1149: 1146: 1128:seismic hazard 1115: 1112: 1022: 1019: 955: 952: 818: 815: 794:Luigi Palmieri 758:United Kingdom 745: 742: 711:geo-sismometro 702:Nicola Cirillo 673: 670: 608: 605: 575: 572: 560:rf seismograph 543:, a branch of 487: 484: 416: 413: 365: 364: 362: 361: 354: 347: 339: 336: 335: 334: 333: 331:Related topics 328: 322: 321: 313: 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