Geographic information on top on the color pattern

Hello everyone, I already plotted map of an area in Africa, as shown below, and i want to plot 1) geographic information on top of the color pattern, 2) Place the legend much down the plot. how to I go about it. Below is the plot with the codes and the some data used

image

gmt begin dilatation4.png

gmt set MAP_FRAME_TYPE plain
gmt set FONT_LABEL 15p

gmt makecpt -Cjet -T-4.0/4.0

gmt coast -R0/47/-20/20 -JM20c -BWSne -Baf -I1/1p,0/200/251 -W1,black -Gwhite -Di -N2/0.25p,black -Na/0.5,black -Swhite
 	gmt surface dila.dat -Gsurface.GRD -T0.5 -I0.01 -R0/47/-20/20
gmt grdimage surface.GRD -Q -C
gmt coast -Ir/grey -Wlightgrey -Swhite  -N1/darkgrey
gmt colorbar -Dx4c/5c+w4c/0.3c+jTC+h+e -Bxa2f0.5+l"Dilatation [per year]" -C
#long lat dilat
12.2 -20 -0.013
12.4 -20 -0.021
12.6 -20 -0.03
12.8 -20 -0.037
13 -20 -0.048
13.2 -20 -0.056
13.4 -20 -0.065
13.6 -20 -0.073
13.8 -20 -0.081
14 -20 -0.087
14.2 -20 -0.097
14.4 -20 -0.11
14.6 -20 -0.123
14.8 -20 -0.138
15 -20 -0.151
15.2 -20 -0.161
15.4 -20 -0.17
15.6 -20 -0.179
15.8 -20 -0.179
16 -20 -0.178
16.2 -20 -0.175
16.4 -20 -0.168
16.6 -20 -0.164
16.8 -20 -0.144
17 -20 -0.127
17.2 -20 -0.111
17.4 -20 -0.086
17.6 -20 -0.067
17.8 -20 -0.043
18 -20 -0.013
18.2 -20 0.02
18.4 -20 0.058
18.6 -20 0.098
18.8 -20 0.137
19 -20 0.183
19.2 -20 0.233
19.4 -20 0.265
22.0 20 -0.102
22.2 20 -0.1
22.4 20 -0.099
22.6 20 -0.098
22.8 20 -0.098
23.0 20 -0.098
23.2 20 -0.101
23.4 20 -0.101
23.6 20 -0.102
23.8 20 -0.103
24.0 20 -0.104
24.2 20 -0.106
24.4 20 -0.108
24.6 20 -0.11
24.8 20 -0.111
25.0 20 -0.11
25.2 20 -0.11
25.4 20 -0.107
25.6 20 -0.107
25.8 20 -0.108
26.0 20 -0.111
26.2 20 -0.115
26.4 20 -0.119
26.6 20 -0.123
26.8 20 -0.128
27.0 20 -0.132
27.2 20 -0.136
27.4 20 -0.14
27.6 20 -0.144
27.8 20 -0.149
28.0 20 -0.154
28.2 20 -0.16
28.4 20 -0.166
28.6 20 -0.172
28.8 20 -0.178
29.0 20 -0.184
29.2 20 -0.192
29.4 20 -0.2
29.6 20 -0.207
29.8 20 -0.216

Such as ?

gmt colorbar -Dx4c/5c+w4c/0.3c+jTC+h+e
-D is your anchor parameter. Currently it is 4cm left and 5cm down the TOP-CENTER (the +j modifier)

I suggest you have a look at the docs for more tweaking with -D :slight_smile: