createkml.py

A python script that creates a kml representation of earthquake data.

createkml.py expects a path to a csv file of the form created by the Geonet csv export call.

The implementation I use to do this reads the file downloaded by a bash script (running as a cron job)

The essential part of this is

wget -O /PATH/TO/FILE.csv "http://wfs.geonet.org.nz/geonet/ows?service=WFS&version=1.0.0&request=GetFeature&typeName=geonet:quake_search_v1&maxFeatures=50&outputFormat=csv"

The format of the file has the following columns, we are only interested in a few of them (in bold)

FID,
publicid,
eventtype,
origintime,
modificationtime,
latitude,
longitude,
depth,
magnitude,
evaluationmethod,
evaluationstatus,
evaluationmode,
earthmodel,
depthtype,
originerror,
usedphasecount,
usedstationcount,
minimumdistance,
azimuthalgap,
magnitudetype,
magnitudeuncertainty,
magnitudestationcount,
origin_geom

See http://info.geonet.org.nz/

The code

Basic stuff, no data integrity checking (this is part of a pipeline in the local implementation).

#!/usr/bin/python

import argparse
import StringIO
import csv
import datetime
import dateutil.parser
import math

#  build the parser
parser = argparse.ArgumentParser(description='Plot earthquakes on a map')
parser.add_argument('filename', help='path/to/csv file')
args = parser.parse_args()

#  open the file provided
f = open(args.filename, 'r')

#  read it in, and create the basic data we will
#  be using
output = StringIO.StringIO(f.read())

#  import in csv file format
data = csv.reader(output)

#   drop the first line
data.next()

#  print out the top of the file
print '<!--?xml version="1.0" encoding="UTF-8"?-->\n\n'
print '\tRecent earthquakes in and around New Zealand'
print '\tSource: GeoNet (www.geonet.org.nz); Created: {}'.format(repr(datetime.datetime.now().isoformat()))

# get the time right noe (UTC)
now = datetime.datetime.utcnow()

# maxdepth is the deepest value
# after which all colour values are clamped

maxdepth = 400.0

for row in data:
  # convert the date to something humans understand
  whendatetime = dateutil.parser.parse(row[3])

  # figure out how far to fade the icon
  # clamp this to ~25% minimum
  difference = (now - whendatetime).total_seconds();
  if difference &gt; 86400:
    difference = 86400
  elif difference &lt; 0:
	difference = 0

  # 'shade' is a two character hex value, 3f-ff,
  # used as the alpha value in the colour applied
  # to the icon
  shade = format(255 - int((float(difference)/86400)* 192),'02x')

  # Generate a colour value for the icon
  # associated with depth.
  # The color ramp will be a logarithmic
  # progression from 00ff00 (shallow)
  # to 0000ff (deep), maxed at maxdepth km?
  depth = float(row[7])

  # fast at shallow, slow at depth
  # multiplier = 255/sqrt(maxdepth)
  # depth2 = math.sqrt(depth)*(255/math.sqrt(maxdepth))

  # slow at shallow, fast at depth
  # divisor = maxdepth/sqrt(255)
  # depth2 = (depth/(maxdepth/math.sqrt(255)))**2

  # flat
  # multiplier = maxdepth/255
  depth2 = depth*(255/maxdepth)

  if depth2 &gt; 255:
    depth2 = 255.0
  elif depth2 &lt; 0:
    depth2 = 0.0
  if depth2 &lt; 128:
    green = 'ff'
    red = format(int(depth2*2),'02x')
  else:
    green = format(255-int((depth2-128)*2),'02x')
    red = 'ff'

  # round magnitude to determine the icon style
  magnitude = float(row[8]);
  magnitudelow = int(math.floor(magnitude))
  if magnitudelow &gt; 9:
    magnitudelow = 9
  elif magnitudelow &lt; 0:
    magnitudelow = 0

  description = '<![CDATA[\n
<div style="text-align: left;">'
  description += '<a href="http://www.geonet.org.nz/quakes/region/newzealand/' + row[1] + '" target="' + row[1] + '"><b>' + row[1] + '</b></a>'
  description += '\n
<b>' + whendatetime.strftime('%H:%M, %d %B %Y') + '</b> (UTC)'
  description += '\n
magnitude: <b>' + str(round(float(row[8]),2)) + '</b>'
  description += '\n
depth: <b>' + str(round(float(row[7]),2)) + 'km</b>'
  description += '</div>
]]>'

  print '\t'
  print '\t\t' + description + ''
  print '\t\t' print '\t\t\n\t\t\t' + row[6] + ',' + row[5] + ',0' print '\t\t\n\t' # print out the bottom of the file print '\n\n'

The script dumps its output to standard output, so I generally redirect this to a file.

There are three magnets suspended from the slinky in the TC1. The first two are centred in the coil. Motion of these magnets from earthquakes are responsible for the induced current in the coil. The third magnet is suspended in the copper tube,  and dampens the system via Lenz’s Law.

The pair of magnets in the coil, and the single magnet in the copper pipe should not touch the coil and tube, respectively, and their tops should be flush with the coil/tube, as shown in the picture.

If the magnets are not in the right vertical position, you can adjust the magnets by threading the screw on the lid up or down. If you need even more vertical adjustment, you can bunch or release rungs clamped in the lid of TC1.

If the magnets are not in the right horizontal position, adjust the knobs on the legs.

If the screenshot of your station is not updating here, consider the following:

1. Is your computer still on? In principle, it can’t be off is power is available: the bios should be set that the machine comes on after a power failure.
2. Is your computer on the network? For macs, you can troubleshoot a wireless connection here, or trouble shoot in general from System Preferences > Network > Assist Me > Diagnostics.
3. Is Jamaseis still running? Jamaseis should be in your startup menu, so that if the computer comes (back) on, so does jamaseis.

If the answer to the three questions is “yes”, check your log file (under the window menu in jamaseis). If you see an error that you can fix, great. If not, send us the log file and restart jamaseis.

Is the TC1 set up right?

If you are unsure if the TC1 is balanced and set up correctly, visit this post

The last 50 earthquakes in and around New Zealand

(regenerated from the data every 10 minutes or so)