tiedown tensions during earthquake

• time: 22:05:35 AST
• Location: 19.045 N, 66.458 w (47 miles North of Ao (33 miles off the north coast),  18.5 miles east of Ao.
• Depth: 14.7 km

• The colored plots are the total tension on td12 (black), td4 (red), td8(green) in kips.
• Data is sampled once a second.
  
• I've removed a linear baseline and put in offsets for display.
• The three plots cover:
• top 21:54 to 22:12 Ast.
• middle:22:00 to 22:12.
• bottom:22:04:32 to 10:07:12 and smooth the data by  9 seconds.
  
• Every two minutes the distomats are measured and cause some ringing in the tiedown tensions.
• times:
• 22:05:35. puerto rican seismic net time of earthquake.
  
• 22:05:50. dashed blue line. Seismometer at AO starts to move.
• 22:06:07  td 8 hits first minimum
• 22:06:20  td 8 hits first maximum
• 22:06:37  td  4 hits first maximum.
• The td8 oscillation took about 25 seconds.
  
• When the earthquake hit the telescope position was: az=148.8 deg, za=12.94 deg. This is perpendicular to td8.
• The total tension in the tiedowns were:166 kips with  td 12:70.9, td 4:47.46,and td 8: 47.48 kips.
  

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