Seismology

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Seismology, The Jesuit Science

Some Jesuits and Their Geophysical Observatories


Frederick Odenbach, S.J.
pioneer of American seismologists

Some Jesuits and Their Geophysical Observatories

Much of this narration is taken from the work of William Stauder, S.J. of St. Louis University and Augustin Udias. The underlying seismic principles are taken from The Random House Encyclopedia.

Jesuits have contributed so much to the development of seismology and seismic prospecting that Seismology has been called The Jesuit Science, and prompted by Dr. Turner, once president of the British Seismological Association, the Society has been congratulated for dominating the field of seismology in America. Daily reports from the Jesuit network were teletyped to the US Coast and Geodetic Survey in Washington and were published annually in the Bulletin of the Seismological Society of America under the title "The Report Or the Jesuit Seismological Association." This Jesuit report was read throughout the world and was highly esteemed even in countries such as Norway where the Jesuits themselves were not allowed. Not only earthquake seismology owes much to Jesuit research, but even more indebted is the field of seismic prospecting, now 60 years old which claims as one of its chief authorities and organizers, Daniel Linehan, S.J. who first put the theories of shallow refraction into practice. Two principal factors contributed to the interest of Jesuits in geophysical phenomena: the educational work of the Jesuits in colleges and universities and their missionary endeavors in remote lands.

54 JESUIT SEISMOLOGICAL STATIONS (established since 1868)
STATION COUNTRY/STATE DATES
Manila Philippines 1868- ------
Baguio
Guam y Butuam
Ambulong
Ktagaytay
Davao
Manila
Tuscalano Ital 1888-1920
Tanarive Madascar 1899-1992
John Carroll Cleveland 1900-1992
Cartuja Granada Spain 1902-1971
(Cartuja)
(Newmann)
Ebro Tarragona 1904-
Grablowitz Spain
Zikawei China 1904-1949
Belen Cuba 1907-1920
Santa Clara California 1907-1958
Stonyhurst England 1908-1947
Mungret Ireland 1908-1915
Riverview Australia 1909-1985
Regis JSA Colorado 1909-1988
Gonzaga JSA Spokane WA 1909-1970
Holy Cross Worcester MA 1909-1934
Marquette JSA Milwaukee WI 1909-1951
Georgetown JSA Wash. DC 1910-1972
Canisius JSA Buffalo NY 1910-------
Saint Louis JSA St. Louis MO 1910-------
Florissant 1928-1974
French Village 1974-------
Cape Girardeau MO 1938-------
Little Rock AR 1930-1958
Onandago 1991-------
Saint Boniface Canada 1910-1922
Fordham JSA New York NY 1910-1977
Loyola JSA New Orleans LA 1910-1960
Spring Hill JSA Mobile AL 1910-1989
Ksara Bekka Lebanon 1910-1979
Loyola JSA Chicago IL 1913-1960
San Calixto La Paz Bolivia 1913-------
Sucre Bolivia 1915-1948
Rathfarnham Castle Ireland 1916-1961
San Bartolome JSA Bogota 1927-1986
Weston JSA Boston MA 1928-------
Saint Louis Island of Jersey 1936-1979
Saint George╣s Kingston Jamaica 1940-1975
Instituto Geo. Bogota Colombia 1941-------
Galerazamba
Chinchina
San Luis Antofagasto Chile 1949-1965
San Francisco California 1950-1964
S. J Brebeuf Montreal Canada 1952-------
Addis Ababa Ethiopia 1957-1978


Seismology

Seismographs are instruments that detect and record the three types of seismic waves, P, S and L. Most seismographs contain a sprung mass (M) that, when an earthquake passes, stays still while the rest of the instrument moves. Some seismographs detect horizontal motion [A] while others detect vertical motion [B]. The trace of the waves is recorded by a vibrating pen on a traveling strip of paper [C] . The time interval between the arrival of the P and S waves can be calculated and this interval applied to a graph (5B) gives the distance between the station and the epicenter.

Seismic waves are basically of two kinds. Primary (P) waves [A] are compressional and cause particles of rock to vibrate backwards and forwards like a coil spring Secondary (S), or shear waves [B] cause the particles to oscillate at right angles to the wave direction like a vibrating guitar string. When P and S waves reach the surface they are converted into long (L) waves [C] which either travel along the surface vibrating horizontally at right angles to the wave direction (known as Love waves) or travel like sea waves (Rayleigh waves). Some of the paths followed are shown in [D].
(from the Random House Encyclopedia)

Seismic wave paths vary with the density of the rock, forming curving patterns as they move away from the focus [1] Primary (P) waves can pass through gases, liquids and solids. The primary waves travel fastest increasing their velocity as they pass through the mantle [2] but decreasing in the outer core [3] only to increase again in the inner core [4] due to varying densities and pressures. Secondary (S) waves travel through solids only and do not penetrate into the dense molten outer core. As the waves travel down they meet concentric layers of increasing density that bend or refract the waves toward the surface along curved paths. The region between [5] and [6] does not receive any direct waves. This area is known to seismologists as the wave shadow zone. Seismic wave propagation has given scientists invaluable information about the interior of the Earth.

The location of an epicenter [ 1 ] is found by plotting its distance from three recording stations [ 2] . Each station notes the different arrival times of P and S waves and uses a graph [B] that allows the distance from the epicenter to be measured. The distance is then used as the radius of a circle around each station [ A] The epicenter of the earthquake is located at the intersection of these three circles.(from the Random House Encyclopedia)

Earthquake ground-shaking intensity is based on a measure of the damage caused in populated areas. The most common intensity scale used is the Wood Neumann or modified Mercalli.
Modified Mercalli scale
1 Earthquake not felt, except by few.
2 Felt on upper floors. Swinging of suspended objects.
3 Quite noticeable indoors. Standing automobiles sway.
4 Felt indoors dishes and windows rattle, standing cars rock. Like a heavy truck hitting a building.
5 Felt by nearly all, many wakened. Fragile objects broken, plaster cracked, trees and poles disturbed.
6 Felt by all. Slight damage, heavy furniture moved.
7 People run outdoors. Average homes slightly damaged substandard ones badly damaged. Noticed by car drivers.
8 Well-built structures slightly damaged others badly damaged. Chimneys and monuments collapse.
9 Well-designed buildings badly damaged, substantial ones greatly damaged, shaken off foundations. Ground cracks.
10 Well-built wood structures destroyed, masonry structures destroyed, landslides, rivers overflow.
11 Few masonry structures left standing. Bridges, underground pipes destroyed. Cracks in ground Earth slumps.
12 Damage total Ground waves seem like sea waves Line of sight disturbed. Objects thrown in the air.
(from the Random House Encyclopedia)

Earthquakes occur in geologically active areas such as mid oceanic ridges and mountain building regions. They can be classified according to the depth of their foci, deep-focus earthquakes (black squares) occurring at depths of between 185 and 400miles (300-650km). inter mediate focus (black dots) 35 to 150 miles(55- 240km). and shallow focus (gray areas) from the surface down to 35 miles (55km)

Release of the pressure that could cause a severe earth quake may be achieved by deliberately causing a number of small quakes in the fault area. Re searchers are investigating the possibility of minimizing the destructive effects of earthquakes by regulating their occurrence. Many small earthquakes, for in stance. may release as much energy as a single devastating one by lessening the strain built up over a period of time [A]. One method of achieving this may be to pump water to act as a lubricant [B] . A number of wells[ 1 ] may be set up along a fault line [ 2] in which stress has been detected. Large quantities of water from a reservoir [3] would then be pumped into the wells to lessen friction between rocks in the fault and allow them to slip smoothly in a series of gentle tremors. Another method of triggering off small ''quakes" may be to explode nuclear devices along a fault plane in the earth. (from the Random House Encyclopedia)



Early Jesuit Observatories


One of the first and most important of the Jesuit colleges was the Roman College (today the Gregorian University), founded in 1551. There Christopher Clavius, S.J. (1537-1612) initiated a tradition of Jesuit research by emphasizing applied mathematics and insisting on the need of the study of mathematics in the program of studies in the humanities. Christopher Scheiner, S.J. (1575-1650) installed the first telescope at the college and carried out observations of sun spots and the rotation of the sun.

Later, another Jesuit, Athanasius Kircher (1601-1680) wrote on geophysical Phenomena such as magnetism, earthquakes and volcanoes, speculating on the structure of the interior of the earth. He developed a unified theory about the interior of the earth, considering it as a heterogeneous and organic body, analogous with a living organism.

The shape and the size of the earth can be computed from the measure of an meridian arc. Roger Boscovich, S.J. and his Jesuit colleagues measured an arc of the meridian of the Papal States. His methods in geophysics and geodesy remained purely geometrical compared with the analytic theory developed later. He developed a theory of the equilibrium of the Earth. He considered the effect of the terrestrial rotation of the Earth's shape in the light of Newtonian mechanics, on the assumption that the terrestrial globe is homogeneous. Later he allowed for heterogeneity by assuming the Earth to consist of a homogeneous nucleus, surrounded by a mantle which is also homogeneous but of lesser density than the core - in the circumstances quite an accurate description of the actual structure of the Earth.

Boscovich's geophysical treatise occasionally reveals unmistakable signs of that genius and intuition. Thus he proposed to mount a long plumb-line in a tower by the sea-shore at high-tide, and predicted that a tide fluctuating by 50 feet in height should cause the plumb-line to oscillate by 2 seconds of arc, an amount which Boscovich thought, could be detected by a microscope. In his life-time Boscovich witnessed mountains, rather than tides, used to yield measurable plumb-line deflections, thus leading to a geophysical determination of the gravitational constant and the mass of the earth before the former quantity could be reliably measured in the laboratory, and the order of magnitude of Boscovich's assumption of 1755 proved to be correct. In his book, Dissertatio de Telluris Figura (1793), Boscovich determined a value of 1/273 for the flattening of the earth. Another book, De Inaequalitate Gravitatis in Diversis Locis (1741), concerned measurements of the variations of gravity.

The first measurement of latitude in China was made in 1702 by a Jesuit director of the observatory near Beijing. Then, following the lead of the Roman College, other observatories were created as Jesuit colleges came to be founded throughout Europe: Marseille in 1702, Lyon in 1745, Graz in 1745, Port-a-Mouson in 1750, Prague in 1751, Tvrnan in Hungary in 1753, Florence in 1755, Parma in 1757, and Milan in 1760. Other observatories were founded by civil governments, then later entrusted to the Jesuits: Lisbon in 1722, Vilnius in 1753, Vienna in 1755, Wurzburg in 1757, Schwetzingen in 1764, and Manheim in 1772.

Missionary work took other Jesuits to such remote lands as India, China, and the newly discovered America, putting these missionary-explorers in contact with different cultures and natural phenomena seldom observed in Europe. Travelling through Mexico and Central and South America, JosÚ de Acosta (1539-1600), for example, described and tried to explain variations of the magnetic declination, the motions of the oceans, earthquakes, volcanic eruptions, and the tides and causes of the winds. Continuing in this tradition Jesuit Missionaries of the eighteenth century engaged in cartographic work, conducted geodetic measurements, measurements of the magnetic inclination and declination, and made careful notations of other geophysical observations in China, Tibet, the Middle East, and in Central and South America.

Seismographs of Wiechert and Macelwane


Modern Jesuit Geophysical Observatories


The beginning of modern Jesuit observatories must be placed in 1838 with the founding of the first two observatories of Stonyhurst in England and Georgetown in Washington, D.C. By 1930 there were thirty in operation throughout the world. Some of these observatories were primarily astronomical but carried out geophysical observations as well. Others were created specifically as meteorological, magnetic, or seismological observatories, usually combining different types of observations but specializing in one field or another.


Some Jesuit Meteorological Observatories



Some Jesuit Geomagnetic Observatories



Some Jesuit Seismological Observatories



Jesuits seismologists at work

Jesuit Seismology in the United States


In the United States the entry of Jesuits into seismology owes its origin to a Jesuit Physics teacher at John Carroll University in Cleveland, Ohio, Frederick Odenbach (1857-1933) who conceived the idea of creating a Jesuit network of seismographic stations across North America which would report to the International Center in Strasbourg. The network started operation in 1911 under the name of the Jesuit Seismological Service with 16 stations, 15 in the United States and one in Canada. The stations had uniform instrumentation consisting of Wiechert 80 kg horizontal seismographs. At the time this was the only homogeneous network covering an entire continent. Unfortunately, interest was not uniform and the Service ceased its operation in 1922. The idea of a Jesuit network was revived by James B. Macelwane (1883-1956) who in 1925 reorganized the Jesuit stations into a newly formed Jesuit Seismological Association (JSA). There were fourteen member stations at Jesuit colleges and universities in the United States. A Central Station was established at Saint Louis University. There, through its recently established Department of Geophysics, Saint Louis University became a resource for graduate education in seismology for a number of Jesuits who then returned as directors to their own institutions.

The Central Station assumed the responsibility on behalf of the JSA of collecting data from member stations, and from other stations around the world, of locating earthquake epicenters and publishing these to the worldwide seismological community. The JSA continued this service until the early 1960's. Then the advent of computers and the ability to handle much larger data sets rendered former methods obsolete and obviated the need of duplicate efforts in the location of earthquakes. At the present time some of the JSA stations have ceased operation, while others, such as Weston Geophysical Observatory of Boston College and the Department of Earth and Atmospheric Science of Saint Louis University have become active geophysical research centers.

Fr. Linehan in Antartica
Observatory readingsShort wave from Antartica
Mass aboard Monte CarloFr. Jim Skehan celebrating the first Mass ever at the volcanic island of Surrtsey
Fr. Linehan and his seismic truck

One measure of the contribution of Jesuits in seismology is given by the number of Jesuit stations, which became part of the World Wide Standard Network (WWSSN) established in 1962. Of the originally selected one hundred and twenty-five stations throughout the world; nine were Jesuit stations: Georgetown (GEO), Weston (WES), Spring Hill (SHA), St. Louis (SLU), Bogota (BOG), LaPaz (LPB), Baguio (BAG), Riverview (RIV), and Addis Ababa (AAE). In 1975 Bogota became the site of one of ten even more advanced Seismic Research Observatories (SRO) and LaPaz an abbreviated station (ASRO) of the same network. Currently St. Louis and Weston are members of the Incorporated Research Institutions for Seismology (IRIS), and St. Louis, through a site at Cathedral Cave in the Ozarks, became the recipient of a prototype next generation broad-band, high gain, digitally recording station.

The history of the Jesuit geophysical observatories forms an important chapter of the scientific activity of Jesuits. Space has not allowed even a cursory mention of the names of the considerable number of Jesuits who worked in the observatories founded by them or of the important contributions made by them, often with the collaboration of non-Jesuit colleagues. Depending as they do on measurements over the entire globe, the nascent geophysical sciences benefited much from the meticulous records kept by the Jesuits of the seventeenth and eighteenth century. Their corporate contribution, as well as that of their confreres of more recent time, are yet to be fully documented and appreciated.


Other Jesuit scientistific apparatus: Secchi's meteorograph and Rueppel's seismograph




More about Jesuit history, tradition and spirituality


Jesuit history . . . an abbreviated summary
Jesuit Education . . . its history, directions and purpose
Jesuit Emblems . . . research of G. Richard Dimler, S.J.
Spiritual Exercises . . . which has changed millions of lives
Retreat in Daily Life . . . what is involved in an Ignatian retreat?
FU Ignatian Tradition . . . that elusive quality so much misquoted
PAUL MIKI'S 400th anniversary the first Japanese Jesuit martyr (TH #8)
All Saints . . . veneration of the saints . . . why?
Saint Thomas . . . forgiveness . . . Easter Sunday and Low Sunday
Computer/Teaching Notes . . . Humberto Eco and Murphy's laws
JESUIT GEOMETERS: 56 Jesuit geometers of the early Society
COMPANIONS OF JESUITS: A tradition of collaboration
GOSPEL ILLUSTRATIONSCompositions of place for the Exercises
Joan of Arc: Insignis* {*outstandingfollower of Christ}

Also visit the Jesuit Resource Page for even more links to things Jesuit.

Influence of Some Early Jesuit Scientists

Adventures of some Jesuit scientists
The 35 lunar craters named to honor Jesuit Scientists: their location and description
Post-Pombal Portugal opinion of Pre-Pombal Jesuit Scientists: a recent conference
Seismology, The Jesuit Science. a Jesuit history of geophysics




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