# http://pyrocko.org - GPLv3
#
# The Pyrocko Developers, 21st Century
# ---|P------/S----------~Lg----------
'''
GEM Global Active Faults Database
(`GEM GAF-DB <https://github.com/GEMScienceTools/gem-global-active-faults>`_).
If the database is not already available, it will be downloaded
automatically on first use.
.. note::
If you use this dataset, please cite:
Styron, Richard, and Marco Pagani. “The GEM Global Active Faults Database.”
Earthquake Spectra, vol. 36, no. 1_suppl, Oct. 2020, pp. 160–180,
doi:10.1177/8755293020944182.
'''
import re
import logging
import numpy as num
from os import path as op
from collections import OrderedDict
import json
from pyrocko import config, util
def parse_3tup(s):
m = re.match(r'^\(?([^,]+),([^,]*),([^,]*)\)$', s)
if m:
return [float(m.group(1)) if m.group(1) else None for i in range(3)]
else:
return [None, None, None]
logger = logging.getLogger('ActiveFaults')
[docs]class ActiveFault(object):
'''
Representation of a single active fault.
'''
__fields__ = OrderedDict([
('lat', list),
('lon', list),
('average_dip', float),
('average_rake', float),
('lower_seis_depth', float),
('upper_seis_depth', float),
('slip_type', str),
])
__slots__ = list(__fields__.keys())
def get_property(self, fault_obj, attr):
try:
values = float(fault_obj['properties'][attr][1:3])
except KeyError:
if attr == 'lower_seis_depth' or attr == 'upper_seis_depth':
values = 0
else:
values = -999
return values
def __init__(self, f):
nodes = f['geometry']['coordinates']
props = f['properties']
lons = [p[0] for p in nodes]
lats = [p[1] for p in nodes]
self.lon = lons
self.lat = lats
self.slip_type = props.get('slip_type', 'Unknown')
for attr, attr_type in self.__fields__.items():
if attr in props:
if props[attr] is None or props[attr] == '':
continue
if isinstance(props[attr], attr_type):
v = props[attr]
elif attr_type is float:
try:
v = parse_3tup(props[attr])[0]
except TypeError:
v = float(props[attr])
elif attr_type is int:
v = int(props[attr])
else:
v = None
setattr(self, attr, v)
def get_surface_line(self):
arr = num.empty((len(self.lat), 2))
for i in range(len(self.lat)):
arr[i, 0] = self.lat[i]
arr[i, 1] = self.lon[i]
return arr
def __str__(self):
d = {attr: getattr(self, attr) for attr in self.__fields__.keys()}
return '\n'.join(['%s: %s' % (attr, val) for attr, val in d.items()])
[docs]class ActiveFaults(object):
'''
GEM Global Active Faults Database (`GEM GAF-DB
<https://github.com/GEMScienceTools/gem-global-active-faults>`_).
:ivar active_faults:
Fault parameters.
:vartype active_faults:
:py:class:`list` of :py:class:`ActiveFault`
'''
URL_GEM_ACTIVE_FAULTS = 'https://raw.githubusercontent.com/cossatot/gem-global-active-faults/master/geojson/gem_active_faults.geojson' # noqa
def __init__(self):
self.fname_active_faults = op.join(
config.config().fault_lines_dir, 'gem_active_faults.geojson')
if not op.exists(self.fname_active_faults):
self.download()
self.active_faults = []
self._load_faults(self.fname_active_faults)
def _load_faults(self, fname):
with open(fname, 'r') as f:
gj = json.load(f)
faults = gj['features']
for f in faults:
fault = ActiveFault(f)
self.active_faults.append(fault)
logger.debug('loaded %d fault', self.nactive_faults)
def download(self):
logger.info('Downloading GEM active faults database...')
util.download_file(self.URL_GEM_ACTIVE_FAULTS,
self.fname_active_faults)
@property
def nactive_faults(self):
return len(self.active_faults)
def nactive_faults_nodes(self):
return int(sum(len(f.lat) for f in self.active_faults))
def get_coords(self):
return num.array([f['coordinates'] for f in self.active_faults])
if __name__ == '__main__':
logging.basicConfig(level=logging.DEBUG)
activefaults = ActiveFaults()
