Historical Seismograms - Evidence from the AD 2000 Izu Islands ...

388 J. R. Goodstein and P. RobertsTable 1. Historical Seismograph Stations in Southern CaliforniaStation Lgfitude Lcigitude Setsnorreter * Sharacteristics Time cf cxrotion0 rd OWHciwe? 36. l3bi 117.94G7 Vuaoc-Lnderson NS, EW Tcrsion/ 10~0 8 1929-1954Berioff L TC=I,Tg:0.2 I929 1954_c Jolla 37.8631 117.2533 .luc.,d- Anderi3n NS, EN' Torsiori/To.U.b 1927-1552Bcn1oif z T ~ I, = rg-c z 1933- 1952Pasodera 31 I483 118 I7 7 Wood-Ander: in hi,FWWcrid-41 drrsori NSVV ~no-Lna~rs~:n EWRenioff ZBenloff EhGenioff NSBenio'f NS,EW,ZLirear strcin NSLinear strcin EWTorsion/ Tc'O.8Torsion/T0=6Tcrsioi 'To= 6To=I,Tg=0.2To = I .Tj = 0.2To=I,Tg =0.2To = I, Tg = 90S t ra in/Tg = 70Stroin/Tg = 70lY2'-1927 iwi. 19411954I927 I9541934-lS37-1938-1940-1938- 19591947 1958H'verside 33.9933 117.3750 Woo3 -Anderson NS,EW Torsion/-o=O.B 1926-Benioff 2ro = I, T~ =0.2 1933-Benioff 7 To= I, Tq: 90 1954Geniofi NS,EW To I , Tg 2 90 1955-Sonto Barbara 34.4417 119.7137 Nood -Anderson NS, EW Torslon/Tg=0.8 1927- 1952; I964eenicf' Z To= I, Tq= 0.21933-1952Tinemoho 37.0550 118.2283 Wood-Andersw NS, EW Torsion/To=O 8 1929-Benioff Z To = I, Tg = 0.2 1929-Benloff Z To=l ,Tg=90 1951-Benioff NS To =I, Tg = 90 1951-Eenioff EW To =I , Tq = 9 0 1954-* Photcgrophlc paper. Does not include short tefrr ard expertmental Instruments.We have not yet any reasonably good time at the head station or at anyof the outlying stations except the experimental pier at the Mt. WilsonObservatory office. Unfortunately the record . . . [there] is defective forthe day in question.There is not much use in determining constants until after the instrumentshave had a little opportunity to settle down . . . to their environment.... I have five graphs of the shock, two written with short-periodlocal earthquake instruments operating at Riverside, two written withshort-period local earthquake instruments operating at the head station,and the defective record written by instrument G. . . . There are no timemarks whatever on that, which is due to a change . . . in the timing circuit.. . . There is no value whatever to the time marks on any of the other fourrecords. They are placed on the records only to indicate the characterof the running, and the constants are only crudely approximate (Wood,1927a).Indeed, in marking the records in pencil on the back in the early years, Woodnoted only the station, the date, and the letters EW or N-S. He explained themeaning of the letters in this way: