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Magnetic airborne survey of Britain#
This is a digitization of an airborne magnetic survey of Britain. Data are sampled where flight lines crossed contours on the archive maps. Contains only the total field magnetic anomaly, not the magnetic field intensity measurements or corrections.
Unfortunately, the exact date of measurements is not available (only the year).
Contains British Geological Survey materials © UKRI 2021.
Original source: British Geological Survey
Pre-processing: Source code for preparation of the original dataset for redistribution in Ensaio
import numpy as np
import pandas as pd
import pygmt
import ensaio
Download and cache the data and return the path to it on disk
fname = ensaio.fetch_britain_magnetic(version=1)
print(fname)
/home/runner/work/_temp/cache/ensaio/v1/britain-magnetic.csv.xz
Load the CSV formatted data with pandas
data = pd.read_csv(fname)
data
Make a PyGMT map with the data points colored by the total field magnetic anomaly.
fig = pygmt.Figure()
scale = np.percentile(data.total_field_anomaly_nt, 95)
pygmt.makecpt(cmap="polar", series=[-scale, scale])
fig.plot(
x=data.longitude,
y=data.latitude,
style="c0.02c",
fill=data.total_field_anomaly_nt,
cmap=True,
projection="M15c",
)
fig.colorbar(frame='af+l"nT"', position="jBL+h+w7c/0.2c+o1/2")
fig.coast(shorelines=True)
fig.basemap(frame="afg")
fig.show()
Total running time of the script: (0 minutes 10.992 seconds)