scholarly journals Pg-wave data-base tabulation from recordings made by vertical short-period systems on the LRSM and New England networks

1983 ◽  
Author(s):  
A.F. Espinosa ◽  
J.A. Michael
Keyword(s):  
1985 ◽  
Vol 45 (4) ◽  
pp. 781-808 ◽  
Author(s):  
Winifred B. Rothenberg

This study is part of a continuing effort to document and date the emergence of a market economy in rural Massachusetts. It uses a probate data base to test for evidence of increased portfolio liquidity, decreased transactions costs, and the appearance of developmental institutional change. A regional capital market, so critical for the industrialization of New England, is found to have emerged in the early 1780s.


1979 ◽  
Vol 69 (6) ◽  
pp. 2037-2061
Author(s):  
A. F. Espinosa

abstract A magnitude (ML) scaling law has been derived from the strong-motion data base of the San Fernando earthquake of February 9, 1971, and the results have been compared with other strong-motion recordings obtained from 62 earthquakes in the Western United States. The relationship derived is ML = 3.21 + 1.35 log10Δ + log10v. An excellent agreement was obtained between the determined ML values in this study and those evaluated by Kanamori and Jennings (1978). This scaling law is applicable to the collected data from 63 earthquakes whose local magnitudes range from about 4.0 to 7.2, recorded at epicentral distances between about 5 to 300 km, and with short-period seismic waves in the range of 0.2 to 3.0 sec. The Long Beach earthquake of 1933, with an ML = 6.3 (PAS) and an ML = 6.43 ± 0.36 as determined by Kanamori and Jennings is in agreement with an ML = 6.49 ± 0.32 obtained in this study. The Imperial Valley earthquake of 1940, with an ML = 6.5 (PAS), compares well with an ML = 6.5 as determined in this study. The Kern County earthquake of 1952, with an ML = 7.2 (BRK), is in fairly good agreement with the ML = 7.0 ± 0.2 obtained in this investigation. This value is significantly lower than the commonly quoted 7.7 value for this event. The San Francisco earthquake of 1957, with an ML = 5.3 (BRK), agrees very well with an ML = 5.3 ± 0.1 as determined in this study. The Parkfield earthquake of 1966 has an ML = 5.8 ± 0.3, which is consistent with the 5.6 (PAS). The procedure developed here is applied to the data base obtained from the Western United States strong-motion recordings. The procedure allows the evaluation of ML for moderate and larger earthquakes from the first integration of the strong-motion accelerograms and allows the direct determination of ML from the scaled amplitudes in a rapid, economical, and accurate manner. It also has allowed for the extension of the trend of the attenuation curve for horizontal particle velocities at distances less than 5 km for different size events.


1992 ◽  
Vol 152 ◽  
pp. 269-274 ◽  
Author(s):  
G. Tancredi ◽  
H. Rickman

The orbital evolution of the whole sample sample of short-period comets was computed by numerical integrations for a time interval of 2000 yr centered on the present epoch. This data base is intended to serve in various studies involving the statistics of orbital evolution and correlation with physical parameters or discovery circumstances. We present some results concerning the following aspects: the evolution of the orbital elements and their past-future asymmetry, statistics on the discovery of comets and on the encounters of comets with Jupiter.


2020 ◽  
Vol 1 (6) ◽  
pp. 198-202
Author(s):  
Peter M. Lewis ◽  
James P. Waddell

It is unusual, if not unique, for three major research papers concerned with the management of the fractured neck of femur (FNOF) to be published in a short period of time, each describing large prospective randomized clinical trials. These studies were conducted in up to 17 countries worldwide, involving up to 80 surgical centers and include large numbers of patients (up to 2,900) with FNOF. Each article investigated common clinical dilemmas; the first paper comparing total hip arthroplasty versus hemiarthroplasty for FNOF, the second as to whether ‘fast track’ care offers improved clinical outcomes and the third, compares sliding hip with multiple cancellous hip screws. Each paper has been deemed of sufficient quality and importance to warrant publication in The Lancet or the New England Journal of Medicine. Although ‘premier’ journals, they only occationally contain orthopaedic studies and thus may not be routinely read by the busy orthopaedic/surgical clinician of any grade. It is therefore our intention with this present article to accurately summarize and combine the results of all three papers, presenting, in our opinion, the most important clinically relevant facts. Cite this article: Bone Joint Open 2020;1-6:198–202.


1991 ◽  
Vol 81 (2) ◽  
pp. 611-621
Author(s):  
William Menke ◽  
Arthur Lerner-Lam

Abstract We measure the polarization of compressional waves from seismograms of chemical explosion of the Ontario-New York-New England refraction experiment recorded by the seven element ECO array in the New York Adirondack mountains. After careful instrument calibration, a precision of about 5° is achieved in measuring the azimuth of the compressional wave polarization direction. The azimuth of the polarization of the onset of the P wave differs from the geometrical source-receiver azimuth by as much as 20°, possible due to deflection of the first-arriving ray by lateral variation in crustal structure. Shortly after the onset of P, the polarization changes from the linear polarization expected of a compressional wave to become very complex. The time of this transition increases with source-receiver distance, from about 0.4 to 0.5 sec at 50 km distance and 0.7 to 0.8 sec at 150 km distance. The complex polarization may be due to the arrival of strongly scattered waves that have propagated mainly in the shallow crust, which would imply that the upper 1 to 2 km of the crust is particularly heterogeneous.


1991 ◽  
Vol 81 (2) ◽  
pp. 379-398 ◽  
Author(s):  
A. Alsaker ◽  
L. B. Kvamme ◽  
R. A. Hansen ◽  
A. Dahle ◽  
H. Bungum

Abstract A new local magnitude ML scale has been developed for Norway, based on a regression analysis of synthesized Wood-Anderson records. The scale is applicable for distances up to more than 1000 km, and the data used comprise 741 short-period recordings at 21 seismic stations from 195 earthquakes in the magnitude range 1 to 5 occurring in and around Norway over the last 20 years. Magnitude corrections for distance have been evaluated in terms of a geometrical spreading term a and an anelastic attenuation term b, and the significant regional crustal differences in the area under investigation made it desirable to develop these for several subsets of the data base. The results for a are generally found to be around the commonly found value of 1.0 (using the Lg phase), while the values of b are found to be around 0.0008, consistent with the weak, intraplate attenuation expected for Norway. Compared to interplate California, this difference in attenuation represents more than a factor of ten in amplitude at a distance of 1000 km. New ML scales are commonly tied to Richter's original definition at the standard reference hypocentral distance of 100 km. The significantly weaker Lg wave attenuation in Norway, however, requires a smaller reference distance. We have chosen a value of 60 km, based on an overall assessment of regional coverage, focal depths, and quality of the data. The resulting ML formula for Norway reads M L = log A w a + a log ( R / 60 ) + b ( R - 60 ) + 2.68 + S , where Awa is synthesized Wood-Anderson amplitude (in mm), R is hypocentral distance (in km), and S is a station correction term that for all 21 stations is found to lie within the range ± 0.22. When using the entire data base, the spreading term a equals 1.02 (± 0.09), and the anelastic attenuation term b equals 0.00080 (± 0.00009). When only strictly continental ray paths are selected, the a value decreases to 0.91 (± 0.11) while the value of b increases to 0.00087 (± 0.00011), a difference which on the average accounts for less than 0.1 magnitude units. While all values used in the regressions have been derived for vertical amplitudes, a separate analysis has shown that these are not significantly different from the horizontal ones, and the new scale is therefore applicable to both. In order to facilitate the practical use of this new ML scale, a relation has also been established between observed seismogram amplitudes in nanometers (corrected for instrument response) and the synthesized Wood-Anderson amplitudes. This relation reads log Awa = 0.925 log Aobs − 2.32. The new ML magnitudes for the events analyzed are in good agreement with those calculated from a previously used relation developed by Båth for Sweden. The ML values have also regressively been related to a data set of Ms magnitudes, yielding the relation Ms = 0.83 ML + 1.09.


1976 ◽  
Vol 45 (4) ◽  
pp. 490-506 ◽  
Author(s):  
Charles D. Cashdollar

Few movements have been so remarkably transformed within such a short period of time as nineteenth century American Unitarianism. In the 1830s, despite its recently acquired denominational independence, it remained theologically quite close its Congregational ancestry. Its most typical leaders of that period —Orville Dewey, John G. Palfrey, Ezra Stiles Gannett, and Nathaniel L. Frothingham—were all men of gentility and moderation, with little taste for theological revolution. Thus their Unitarianism differed from orthodox New England theology in degree rather than kind and still formed, as one contemporary put it, “the liberal side of the old Congregational body.” Men like Frothingham, who filled the prestigious pulpit of Boston's First Church, continued to believe in a supernatural deity revealed by miracles and divinely inspired Scripture. They placed only limited faith in man. Although not totally depraved, humanity was filled largely with evil and needed divine mediation for salvation. Jesus, who provided this mediation, was described as “the divinely inspired Son of the Father.” The social views of these men, based as they were on the assumption that God had ordained and established the social institutions of the day, were predominantly conservative.3 Within a generation, however, this Old Unitarianism had dissolved. Not everyone changed, of course. Some Conservatives maintained the traditional views until their deaths, but they quickly became a minority as a New Unitarianism emerged.


1988 ◽  
Vol 59 (4) ◽  
pp. 173-181 ◽  
Author(s):  
Alan L. Kafka

Abstract Within southern New england (SNE) and adjacent areas lies a variety of tectonic regions extending from the ancient North American craton to the Avalonian Terrane. This region, which is part of the northern Appalachians, has had a moderate level of seismic activity throughout its recorded history. Although the geology and geophysics of SNE have been studied extensively, it has been difficult to correlate the seismic activity in this region with geologic structures mapped on the earth’s surface. The distribution of earthquakes located by regional seismic networks in SNE generally resembles that of historical earthquakes in this region. In both the network and historical records, a cluster of earthquakes occurs near Moodus, CT and more diffuse seismicity occurs in the eastern coastal regions. Both data sets show earthquake activity in the vicinity of the 1755 earthquake that occurred on the coast of Cape Ann, MA, as well as seismicity near the boundary between southwestern CT and NY State. Aside from these very general similarities, the location uncertainties of the historical earthquakes make it difficult to compare the two records of seismicity in any greater detail. Information about the lateral variation of seismic velocities in the shallow crust beneath SNE has been obtained from studies of dispersion of short-period, fundamental-mode Rayleigh waves (Rg). Rg waves with periods between about 0.2 and 2.5 sec have been studied, and dispersive properties of Rg in that period range are sensitive to lateral variation in the upper few kilometers of the crust. Based on Rg dispersion studies, it appears that SNE can be divided into regions of distinct shallow crustal structure. The pattern of lateral variation is Rg dispersion is similar to the pattern of teleseismic residuals and gravity anomalies, suggesting that the lateral variation revealed by the Rg studies extends deeper into the crust. These results, however, do not reveal any obvious correlations between crustal features and seismicity.


1993 ◽  
Vol 13 (4) ◽  
pp. 333-350
Author(s):  
Alan E. Strauss

This article examines the type and distribution of raw materials used to manufacture Middle Woodland Corner-Notched (Jack's Reef) points across the six-state New England region. A data base of several hundred points was used to determine if this point type clustered in certain geographical areas or features and what raw materials were used for their manufacture. Finally, the implications for trade and social interaction are examined.


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