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50-526: A major goal of USArray was to collect detailed seismic images of the North American lithosphere . The data collected from USArray was integrated with geologic observations made on the Earth's surface to help determine the geologic history of North America, as well as to better understand that geologic processes that are at work today. USArray consists of four "observatories": The Transportable Array (TA)

100-481: A conchologist he was held in high esteem, but while he recognised the similarity of fossil mollusca to living forms, he regarded them as inorganic imitations produced in the rocks. Lister employed his daughters from an early age. His daughters, Anne Lister , and Susanna Lister were both credited as his illustrators and engravers. In 1683 he communicated to the Royal Society (1684 ), an ingenious proposal for

150-408: A 'plastic virtue latent in the earth' the origin of fossil shells and fishes; and Lister, to his accurate account of British shells, in 1678, added the fossil species, under the appellation of turbinated and bivalve stones . 'Either,' said he, 'these were terriginous, or if otherwise, the animals they so exactly represent have become extinct . This writer appears to have been the first who was aware of

200-519: A function of time, created by a seismograph is called a seismogram . A seismologist is a scientist works in basic or applied seismology. Scholarly interest in earthquakes can be traced back to antiquity. Early speculations on the natural causes of earthquakes were included in the writings of Thales of Miletus ( c.  585 BCE ), Anaximenes of Miletus ( c.  550 BCE ), Aristotle ( c.  340 BCE ), and Zhang Heng (132 CE). In 132 CE, Zhang Heng of China's Han dynasty designed

250-453: A mantle of silicates, surrounding a core of iron. In 1906 Richard Dixon Oldham identified the separate arrival of P waves , S-waves and surface waves on seismograms and found the first clear evidence that the Earth has a central core. In 1909, Andrija Mohorovičić , one of the founders of modern seismology, discovered and defined the Mohorovičić discontinuity . Usually referred to as

300-399: A month after the event. The first observations of normal modes were made in the 1960s as the advent of higher fidelity instruments coincided with two of the largest earthquakes of the 20th century the 1960 Valdivia earthquake and the 1964 Alaska earthquake . Since then, the normal modes of the Earth have given us some of the strongest constraints on the deep structure of the Earth. One of

350-412: A near-surface explosion, and are much weaker for deep earthquake sources. Both body and surface waves are traveling waves; however, large earthquakes can also make the entire Earth "ring" like a resonant bell. This ringing is a mixture of normal modes with discrete frequencies and periods of approximately an hour or shorter. Normal mode motion caused by a very large earthquake can be observed for up to

400-473: A new sort of maps of countries; together with tables of sands and clays, such as are chiefly found in the north parts of England. In this essay he suggested the preparation of a soil or mineral map of the country, and thereby is justly credited with being the first to realise the importance of a geological survey. Charles Lyell speaks of Lister in his Principles of Geology as follows: Dr. Plot , in his 'Natural History of Oxfordshire.' (1677) attributed to

450-449: A particular location within a particular time-span, and they are routinely used in earthquake engineering . Public controversy over earthquake prediction erupted after Italian authorities indicted six seismologists and one government official for manslaughter in connection with a magnitude 6.3 earthquake in L'Aquila, Italy on April 5, 2009 . A report in Nature stated that the indictment

500-683: A physician and settled at York in 1670 to practice medicine. He became Fellow of the Royal Society on 2 November 1671. He practised medicine at York until 1683, when he moved to London. In 1684 he received the degree of M.D. at Oxford on the recommendation of the Chancellor. In 1687 became F.R.C.P. Lister bought Carlton Hall in Craven in the West Riding of Yorkshire. He attended the Earl of Portland when he

550-501: A process known as seismic tomography . The density of the TA network — typical station spacing of about 70 km — provided a level of resolution not previously available in many parts of the country and provided finer details of the lithosphere under parts of North America. The Flexible Array was a pool of portable seismic instruments available for short-term high-density observations of particular areas of interest. The Reference Network

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600-518: A special meeting in L'Aquila the week before the earthquake occurred, scientists and officials were more interested in pacifying the population than providing adequate information about earthquake risk and preparedness. In locations where a historical record exists it may be used to estimate the timing, location and magnitude of future seismic events. There are several interpretative factors to consider. The epicentres or foci and magnitudes of historical earthquakes are subject to interpretation meaning it

650-607: A variety of people including family, friends and other scientists. Abstracts of these letters have been published on line. The memorial inscription for Lister in Clapham church is now lost. It read: Near this place is buried the body of MARTIN LISTER, Doctor of Physick, a Member of the Royal Society, and one of Queen Ann's Physicians, who departed this life, the second day of February 1711–12. Lister contributed numerous articles on natural history, medicine and antiquities to

700-569: A very short time frame in a seismic cycle . Engineering seismology is the study and application of seismology for engineering purposes. It generally applied to the branch of seismology that deals with the assessment of the seismic hazard of a site or region for the purposes of earthquake engineering. It is, therefore, a link between earth science and civil engineering . There are two principal components of engineering seismology. Firstly, studying earthquake history (e.g. historical and instrumental catalogs of seismicity) and tectonics to assess

750-538: Is called a seismograph . Networks of seismographs continuously record ground motions around the world to facilitate the monitoring and analysis of global earthquakes and other sources of seismic activity. Rapid location of earthquakes makes tsunami warnings possible because seismic waves travel considerably faster than tsunami waves. Seismometers also record signals from non-earthquake sources ranging from explosions (nuclear and chemical), to local noise from wind or anthropogenic activities, to incessant signals generated at

800-413: Is possible that 5–6 Mw earthquakes described in the historical record could be larger events occurring elsewhere that were felt moderately in the populated areas that produced written records. Documentation in the historic period may be sparse or incomplete, and not give a full picture of the geographic scope of an earthquake, or the historical record may only have earthquake records spanning a few centuries,

850-476: The Philosophical Transactions . He was the first arachnologist and conchologist, and provided an unprecedented picture of a seventeenth-century virtuoso. Lister is recognized for his discovery of ballooning spiders and as the father of conchology , but it is less well known that he invented the histogram , provided Newton with alloys, and donated the first significant natural history collections to

900-620: The Ashmolean Museum in Oxford. Just as Lister was the first to make a systematic study of spiders and their webs, this biography is the first to analyze the significant webs of knowledge, patronage, and familial and gender relationships that governed his life as a scientist and physician. His principal works were Historiae animalium Angliae tres tractatus (1678) which was the first organised, systematic publication on shells; Historiae Conchyliorum (1685 1692), and Conchyliorum Bivalvium (1696). As

950-496: The Earth or other planetary bodies . It also includes studies of earthquake environmental effects such as tsunamis as well as diverse seismic sources such as volcanic, tectonic, glacial, fluvial , oceanic microseism , atmospheric, and artificial processes such as explosions and human activities . A related field that uses geology to infer information regarding past earthquakes is paleoseismology . A recording of Earth motion as

1000-451: The VAN method . Most seismologists do not believe that a system to provide timely warnings for individual earthquakes has yet been developed, and many believe that such a system would be unlikely to give useful warning of impending seismic events. However, more general forecasts routinely predict seismic hazard . Such forecasts estimate the probability of an earthquake of a particular size affecting

1050-514: The "Moho discontinuity" or the " Moho ," it is the boundary between the Earth 's crust and the mantle . It is defined by the distinct change in velocity of seismological waves as they pass through changing densities of rock. In 1910, after studying the April 1906 San Francisco earthquake , Harry Fielding Reid put forward the " elastic rebound theory " which remains the foundation for modern tectonic studies. The development of this theory depended on

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1100-732: The Ashmolean several volumes of Lister's letters and around 40 of his notebooks, which he had bought at auction. In 1858 the Trustees of the Museum offered a transfer of their written artefacts to the Bodleian, and in 1860 more than 3700 volumes were received by the Library. Lister's books and manuscripts form almost a third of this initial collection, making him its second-most represented donor next to Elias Ashmole. His series consists of c. 1260 volumes dating from

1150-594: The NSF SAGE Facility Data Services, operated by EarthScope Consortium (previously known as the IRIS Data Management Center). Seismic Seismology ( / s aɪ z ˈ m ɒ l ə dʒ i , s aɪ s -/ ; from Ancient Greek σεισμός ( seismós ) meaning " earthquake " and -λογία ( -logía ) meaning "study of") is the scientific study of earthquakes (or generally, quakes ) and the generation and propagation of elastic waves through

1200-595: The behaviour and causation of earthquakes. The earliest responses include work by John Bevis (1757) and John Michell (1761). Michell determined that earthquakes originate within the Earth and were waves of movement caused by "shifting masses of rock miles below the surface". In response to a series of earthquakes near Comrie in Scotland in 1839, a committee was formed in the United Kingdom in order to produce better detection methods for earthquakes. The outcome of this

1250-532: The considerable progress of earlier independent streams of work on the behavior of elastic materials and in mathematics. An early scientific study of aftershocks from a destructive earthquake came after the January 1920 Xalapa earthquake . An 80 kg (180 lb) Wiechert seismograph was brought to the Mexican city of Xalapa by rail after the earthquake. The instrument was deployed to record its aftershocks. Data from

1300-682: The continuity over large districts of the principal groups of strata in the British series, and who proposed the construction of regular geological maps. He was a benefactor of the Ashmolean Museum in Oxford. The ridge Dorsa Lister in the Sea of Serenity on the Moon was named after him. Before he died in 1712, Lister donated over a thousand books and manuscripts to the Ashmolean Museum, most of which were medical and scientific works. In 1769 John Fothergill gifted

1350-512: The earth to a resolution of several hundred kilometers. This has enabled scientists to identify convection cells and other large-scale features such as the large low-shear-velocity provinces near the core–mantle boundary . Forecasting a probable timing, location, magnitude and other important features of a forthcoming seismic event is called earthquake prediction . Various attempts have been made by seismologists and others to create effective systems for precise earthquake predictions, including

1400-769: The earthquakes that could occur in a region and their characteristics and frequency of occurrence. Secondly, studying strong ground motions generated by earthquakes to assess the expected shaking from future earthquakes with similar characteristics. These strong ground motions could either be observations from accelerometers or seismometers or those simulated by computers using various techniques, which are then often used to develop ground motion prediction equations (or ground-motion models) [1] . Seismological instruments can generate large amounts of data. Systems for processing such data include: Martin Lister Martin Lister FRS (12 April 1639 – 2 February 1712)

1450-456: The first attempts at the scientific study of earthquakes followed the 1755 Lisbon earthquake. Other notable earthquakes that spurred major advancements in the science of seismology include the 1857 Basilicata earthquake , the 1906 San Francisco earthquake, the 1964 Alaska earthquake , the 2004 Sumatra-Andaman earthquake , and the 2011 Great East Japan earthquake . Seismic waves produced by explosions or vibrating controlled sources are one of

1500-578: The first known seismoscope . In the 17th century, Athanasius Kircher argued that earthquakes were caused by the movement of fire within a system of channels inside the Earth. Martin Lister (1638–1712) and Nicolas Lemery (1645–1715) proposed that earthquakes were caused by chemical explosions within the Earth. The Lisbon earthquake of 1755 , coinciding with the general flowering of science in Europe , set in motion intensified scientific attempts to understand

1550-415: The first waves to appear on a seismogram as they are the fastest moving waves through solids. S-waves are transverse waves that move perpendicular to the direction of propagation. S-waves are slower than P-waves. Therefore, they appear later than P-waves on a seismogram. Fluids cannot support transverse elastic waves because of their low shear strength, so S-waves only travel in solids. Surface waves are

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1600-473: The foundation of modern instrumental seismology and carried out seismological experiments using explosives. He is also responsible for coining the word "seismology." In 1889 Ernst von Rebeur-Paschwitz recorded the first teleseismic earthquake signal (an earthquake in Japan recorded at Pottsdam Germany). In 1897, Emil Wiechert 's theoretical calculations led him to conclude that the Earth's interior consists of

1650-432: The global seismographic monitoring has been for the detection and study of nuclear testing . Because seismic waves commonly propagate efficiently as they interact with the internal structure of the Earth, they provide high-resolution noninvasive methods for studying the planet's interior. One of the earliest important discoveries (suggested by Richard Dixon Oldham in 1906 and definitively shown by Harold Jeffreys in 1926)

1700-406: The interior of the materials; surface waves that travel along surfaces or interfaces between materials; and normal modes , a form of standing wave. There are two types of body waves, pressure waves or primary waves (P-waves) and shear or secondary waves ( S waves ). P-waves are longitudinal waves that involve compression and expansion in the direction that the wave is moving and are always

1750-481: The ocean floor and coasts induced by ocean waves (the global microseism ), to cryospheric events associated with large icebergs and glaciers. Above-ocean meteor strikes with energies as high as 4.2 × 10 J (equivalent to that released by an explosion of ten kilotons of TNT) have been recorded by seismographs, as have a number of industrial accidents and terrorist bombs and events (a field of study referred to as forensic seismology ). A major long-term motivation for

1800-436: The ocean processes responsible for the global background seismic microseism . By the 1960s, Earth science had developed to the point where a comprehensive theory of the causation of seismic events and geodetic motions had come together in the now well-established theory of plate tectonics . Seismic waves are elastic waves that propagate in solid or fluid materials. They can be divided into body waves that travel through

1850-473: The primary methods of underground exploration in geophysics (in addition to many different electromagnetic methods such as induced polarization and magnetotellurics ). Controlled-source seismology has been used to map salt domes , anticlines and other geologic traps in petroleum -bearing rocks , faults , rock types, and long-buried giant meteor craters . For example, the Chicxulub Crater , which

1900-455: The regicide and also of Matthew Lister , physician to Anne , queen of James I , and to Charles I . He was also the uncle of Sarah Churchill, Duchess of Marlborough who corresponded with him throughout her life. Lister was educated at Melton Mowbray , Leicestershire under Mr Barwick and matriculated at St John's College, Cambridge in 1658. He graduated in 1658/9, and was elected a fellow in 1660. In 1668 he travelled to France to study as

1950-400: The result of P- and S-waves interacting with the surface of the Earth. These waves are dispersive , meaning that different frequencies have different velocities. The two main surface wave types are Rayleigh waves , which have both compressional and shear motions, and Love waves , which are purely shear. Rayleigh waves result from the interaction of P-waves and vertically polarized S-waves with

2000-416: The seismograph would eventually determine that the mainshock was produced along a shallow crustal fault. In 1926, Harold Jeffreys was the first to claim, based on his study of earthquake waves, that below the mantle, the core of the Earth is liquid. In 1937, Inge Lehmann determined that within Earth's liquid outer core there is a solid inner core . In 1950, Michael S. Longuet-Higgins elucidated

2050-476: The surface and can exist in any solid medium. Love waves are formed by horizontally polarized S-waves interacting with the surface, and can only exist if there is a change in the elastic properties with depth in a solid medium, which is always the case in seismological applications. Surface waves travel more slowly than P-waves and S-waves because they are the result of these waves traveling along indirect paths to interact with Earth's surface. Because they travel along

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2100-399: The surface of the Earth, their energy decays less rapidly than body waves (1/distance vs. 1/distance ), and thus the shaking caused by surface waves is generally stronger than that of body waves, and the primary surface waves are often thus the largest signals on earthquake seismograms . Surface waves are strongly excited when their source is close to the surface, as in a shallow earthquake or

2150-781: Was a network of 400 high-quality broadband seismographs on temporary sites that marched across the conterminous United States. The initial deployment, in August 2007, was in the western quarter of the United States. Since then the stations on the western edge were regularly relocated to the eastern edge at a rate of about four stations per week. The Transportable Array reached the East Coast in 2013, and wound up in 2017, having occupied nearly 2000 sites. An archive of stations are listed online. Geological structures can be mapped by observing how they affect seismic waves from local and distant earthquakes,

2200-520: Was ambassador to France in 1698. He was physician to Queen Anne from 1709 until his death. He died at Epsom at the age of 72 and was buried at Clapham Church. He bequeathed his books and copper-plates to the University of Oxford. Lister was a prolific correspondent. More than 2,000 letters written by and to him survive in the Bodleian Library , Oxford and other repositories. They are to and from

2250-527: Was an English naturalist and physician. His daughters Anne and Susanna were two of his illustrators and engravers. Lister was born at Radcliffe , near Buckingham , the son of Sir Martin Lister MP for Brackley in the Long Parliament and his wife Susanna Temple , a daughter of Sir Alexander Temple . Lister was connected to a number of well known individuals. He was the nephew of both James Temple ,

2300-596: Was an additional 100+ permanent stations located on approximately 300 km spacings that provided a long-term reference frame. These also augmented the USGS Advanced National Seismic System (ANSS), providing seismic observations in areas where instrumentation had been lacking. The Magnetotelluric Array measured naturally occurring electric and magnetic fields. It consisted of seven permanent magnetotelluric (MT) stations and twenty portable stations. Data from these instruments are available from

2350-591: Was caused by an impact that has been implicated in the extinction of the dinosaurs , was localized to Central America by analyzing ejecta in the Cretaceous–Paleogene boundary , and then physically proven to exist using seismic maps from oil exploration . Seismometers are sensors that detect and record the motion of the Earth arising from elastic waves. Seismometers may be deployed at the Earth's surface, in shallow vaults, in boreholes, or underwater . A complete instrument package that records seismic signals

2400-409: Was that the outer core of the earth is liquid. Since S-waves do not pass through liquids, the liquid core causes a "shadow" on the side of the planet opposite the earthquake where no direct S-waves are observed. In addition, P-waves travel much slower through the outer core than the mantle. Processing readings from many seismometers using seismic tomography , seismologists have mapped the mantle of

2450-415: Was the production of one of the first modern seismometers by James David Forbes , first presented in a report by David Milne-Home in 1842. This seismometer was an inverted pendulum, 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. From 1857, Robert Mallet laid

2500-711: Was widely seen in Italy and abroad as being for failing to predict the earthquake and drew condemnation from the American Association for the Advancement of Science and the American Geophysical Union . However, the magazine also indicated that the population of Aquila do not consider the failure to predict the earthquake to be the reason for the indictment, but rather the alleged failure of the scientists to evaluate and communicate risk. The indictment claims that, at

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