.. index:: ! events
gmt events |-J|parameters |SYN_OPT-Rz| |-T|now [ table ] [ |-A|r[dpu][c|i]|s ] [ |SYN_OPT-B| ] [ |-C|cpt ] [ |-D|[j|J]dx[/dy][+v[pen]] ] [ |-E|s|t[+o|Odt][+rdt][+pdt][+ddt][+fdt][+ldt] ] [ |-F|[+aangle][+ffont][+jjustify][+r[first]|z[format]] ] [ |-G|color ] [ |-H|labelbox ] [ |-L|[length|t] ] [ |-M|i|s|t[val1][+cval2] ] [ |-N|[c|r] ] [ |-Q|prefix ] [ |-S|symbol[size] ] [ |SYN_OPT-U| ] [ |SYN_OPT-V| ] [ |-W|pen ] [ |SYN_OPT-X| ] [ |SYN_OPT-Y| ] [ |-Z|command ] [ |SYN_OPT-bi| ] [ |SYN_OPT-di| ] [ |SYN_OPT-e| ] [ |SYN_OPT-f| ] [ |SYN_OPT-h| ] [ |SYN_OPT-i| ] [ |SYN_OPT-p| ] [ |SYN_OPT-qi| ] [ |SYN_OPT-w| ] [ |SYN_OPT-:| ] [ |SYN_OPT--| ]
To show the display of events visible for May 1, 2018 given the catalog of large (>5) magnitude earthquakes that year, using a 2-day rise time during which we boost symbol size by a factor of 5 and wash out the color, followed by a decay over 6 days and then a final shrinking to half size and darken the color, we may try
gmt begin layer
gmt convert "https://earthquake.usgs.gov/fdsnws/event/1/query.csv?starttime=2018-01-01%2000:00:00&endtime=2018-12-31%2000:00:00&minmagnitude=5&orderby=time-asc" \
-i2,1,3,4+s50,0 -hi1 > q.txt
gmt makecpt -Cred,green,blue -T0,70,300,10000
gmt events -Rg -JG200/5/6i -Baf q.txt -SE- -C --TIME_UNIT=d -T2018-05-01T -Es+r2+d6 -Ms5+c0.5 -Mi1+c-0.6 -Mt+c0
gmt end show
To convert the time-series seismic_trace.txt (time, amplitude) into a (time, amplitude, time) file that events can plot with a variable pen (by plotting densely placed circles), we use -i to ensure we read the time-column twice and then use a dpu of 80 pixels per cm (HD movie) and the projection parameters we will use when making the plot, e.g.,:
gmt events seismic_trace.txt -R1984-09-10T03:15/1984-09-10T03:45/-15/15 -JX20cT/10c -Ar80c -i0,1,0 > seismic_trace_pts.txt
Note: If your :term:`PROJ_LENGTH_UNIT` is set to inch then you need to use the equivalent dpu of 200 pixels per inch for HD, or you specify -Ar200i.