.. DO NOT EDIT.
.. THIS FILE WAS AUTOMATICALLY GENERATED BY SPHINX-GALLERY.
.. TO MAKE CHANGES, EDIT THE SOURCE PYTHON FILE:
.. "api/gallery/seismology/plot_09_richter_magnitude.py"
.. LINE NUMBERS ARE GIVEN BELOW.

.. only:: html

    .. note::
        :class: sphx-glr-download-link-note

        :ref:`Go to the end <sphx_glr_download_api_gallery_seismology_plot_09_richter_magnitude.py>`
        to download the full example code or to run this example in your browser via JupyterLite.

.. rst-class:: sphx-glr-example-title

.. _sphx_glr_api_gallery_seismology_plot_09_richter_magnitude.py:


Richter's magnitude scale (1935)
================================

Charles Richter ranked southern California earthquakes by the logarithm of
the peak amplitude on a Wood-Anderson seismometer, corrected for distance.
Magnitude 3 is a 1 mm trace at 100 km, and each unit is a tenfold amplitude.
The distance correction used here is Hutton and Boore's 1987 calibration.

.. GENERATED FROM PYTHON SOURCE LINES 10-28



.. image-sg:: /api/gallery/seismology/images/sphx_glr_plot_09_richter_magnitude_001.png
   :alt: Same magnitude, smaller trace farther away
   :srcset: /api/gallery/seismology/images/sphx_glr_plot_09_richter_magnitude_001.png
   :class: sphx-glr-single-img





.. code-block:: Python


    import matplotlib.pyplot as plt
    import numpy as np

    from earthsciencekit.seismology import local_magnitude

    distance = np.linspace(10e3, 600e3, 300)
    assert np.isclose(local_magnitude(1e-3, 100e3), 3)
    fig, ax = plt.subplots()
    for magnitude in [2, 3, 4, 5]:
        # Invert the scale for the amplitude that the same event produces at each distance.
        amplitude = 1e-3 * 10 ** (magnitude - local_magnitude(1e-3, distance))
        np.testing.assert_allclose(local_magnitude(amplitude, distance), magnitude)
        ax.semilogy(distance / 1e3, amplitude * 1e3, label=f"ML {magnitude}")
    ax.set(xlabel="hypocentral distance [km]", ylabel="Wood-Anderson amplitude [mm]", title="Same magnitude, smaller trace farther away")
    ax.legend()

    plt.show()


.. rst-class:: sphx-glr-timing

   **Total running time of the script:** (0 minutes 0.187 seconds)


.. _sphx_glr_download_api_gallery_seismology_plot_09_richter_magnitude.py:

.. only:: html

  .. container:: sphx-glr-footer sphx-glr-footer-example

    .. container:: lite-badge

      .. image:: images/jupyterlite_badge_logo.svg
        :target: ../../../lite/lab/index.html?path=api/gallery/seismology/plot_09_richter_magnitude.ipynb
        :alt: Launch JupyterLite
        :width: 150 px

    .. container:: sphx-glr-download sphx-glr-download-jupyter

      :download:`Download Jupyter notebook: plot_09_richter_magnitude.ipynb <plot_09_richter_magnitude.ipynb>`

    .. container:: sphx-glr-download sphx-glr-download-python

      :download:`Download Python source code: plot_09_richter_magnitude.py <plot_09_richter_magnitude.py>`

    .. container:: sphx-glr-download sphx-glr-download-zip

      :download:`Download zipped: plot_09_richter_magnitude.zip <plot_09_richter_magnitude.zip>`


.. only:: html

 .. rst-class:: sphx-glr-signature

    `Gallery generated by Sphinx-Gallery <https://sphinx-gallery.github.io>`_