Volcanic hazard map for <a href="https://en.wikipedia.org/wiki/Nevado_del_Ruiz" class="extiw" title="w:Nevado del Ruiz">Nevado del Ruiz</a>. Lahars from 1985 eruption (which killed around 23,000 people) shown in red.
<p>Original caption:
</p>
"Map showing hazards expected from an eruption of Nevado del Ruiz, Colombia. Such a map was prepared by INGEOMINAS (Colombian Institute of Geology and Mines) and circulated 1 month prior to the November 13, 1985, eruption of Nevado del Ruiz. Map shows danger from mudflows in the valley occupied by the town of Armero, Colombia, as well as areas affected by the hazards that resulted from this eruption. Circle denotes 20-kilometer limit."
Wright, Thomas L. and Pierson, Thomas C.
Page 21 in Wright, Thomas L. and Pierson, Thomas C. (1992). <i><a rel="nofollow" class="external text" href="https://pubs.er.usgs.gov/djvu/CIR/circ_1073.djvu">Living with volcanoes</a></i> (DJVU format), USGS Circular 1073. Bibliographic information and link to DJVU reader are online <a rel="nofollow" class="external text" href="https://pubs.er.usgs.gov/usgspubs/cir/cir1073">here</a>.