obspy.core - Core classes of ObsPy

This package contains common methods and classes for ObsPy. It includes the Stream, Trace, UTCDateTime, Stats classes and methods for reading seismogram files.


The ObsPy Development Team (devs@obspy.org)


GNU Lesser General Public License, Version 3 (https://www.gnu.org/copyleft/lesser.html)

Waveform Data


Seismograms of various formats (e.g. SAC, MiniSEED, GSE2, SEISAN, Q, etc.) can be imported into a Stream object using the read() function.

Streams are list-like objects which contain multiple Trace objects, i.e. gap-less continuous time series and related header/meta information.

Each Trace object has the attribute data pointing to a NumPy ndarray of the actual time series and the attribute stats which contains all meta information in a dict-like Stats object. Both attributes starttime and endtime of the Stats object are UTCDateTime objects. A multitude of helper methods are attached to Stream and Trace objects for handling and modifying the waveform data.



A Stream with an example seismogram can be created by calling read() without any arguments. Local files can be read by specifying the filename, files stored on http servers (e.g. at https://examples.obspy.org) can be read by specifying their URL. For details and supported formats see the documentation of read().

>>> from obspy import read
>>> st = read()
>>> print(st)  
3 Trace(s) in Stream:
BW.RJOB..EHZ | 2009-08-24T00:20:03.000000Z - ... | 100.0 Hz, 3000 samples
BW.RJOB..EHN | 2009-08-24T00:20:03.000000Z - ... | 100.0 Hz, 3000 samples
BW.RJOB..EHE | 2009-08-24T00:20:03.000000Z - ... | 100.0 Hz, 3000 samples
>>> tr = st[0]
>>> print(tr)  
BW.RJOB..EHZ | 2009-08-24T00:20:03.000000Z - ... | 100.0 Hz, 3000 samples
>>> tr.data
array([ 0.        ,  0.00694644,  0.07597424, ...,  1.93449584,
        0.98196204,  0.44196924])
>>> print(tr.stats)  
         network: BW
         station: RJOB
         channel: EHZ
       starttime: 2009-08-24T00:20:03.000000Z
         endtime: 2009-08-24T00:20:32.990000Z
   sampling_rate: 100.0
           delta: 0.01
            npts: 3000
           calib: 1.0
>>> tr.stats.starttime
UTCDateTime(2009, 8, 24, 0, 20, 3)

Event Metadata

Event metadata are handled in a hierarchy of classes closely modelled after the de-facto standard format QuakeML. See the IPython notebooks mentioned in the ObsPy Tutorial for more detailed usage examples. See read_events() and Catalog.write() for supported formats.


Station Metadata

Station metadata are handled in a hierarchy of classes closely modelled after the de-facto standard format FDSN StationXML which was developed as a human readable XML replacement for Dataless SEED. See obspy.core.inventory for more details. See read_inventory() and Inventory.write() for supported formats.


Classes & Functions


Read waveform files into an ObsPy Stream object.


List like object of multiple ObsPy Trace objects.


An object containing data of a continuous series, such as a seismic trace.


A container for additional header information of a ObsPy Trace object.


A UTC-based datetime object.


Read event files into an ObsPy Catalog object.


This class serves as a container for Event objects.


The class Event describes a seismic event which does not necessarily need to be a tectonic earthquake.


Function to read inventory files.


The root object of the Network-> Station-> Channel hierarchy.



Module for handling ObsPy Trace and Stats objects.


Module for handling ObsPy Stream objects.


Module containing a UTC-based datetime class.


Module handling event metadata


Module for handling station metadata


Various utilities for ObsPy


Tools for creating and merging previews.