How to splice adjacent dem files and display thumbnails on Google Earth

Hello, professors, I downloaded two adjacent dem files in grd format from the official website of gmtsardem, because the comparison range of my research area is relatively large, which exceeds the download limit within 4° of the website。
The downloaded dem file is very good, and the kml format file is attached. It is very convenient to check whether the location is consistent with what I need through Google Earth.
By looking up I used the command :[gmt grdblend file1.grd file2.grd merged.grd] To splice two adjacent dem got the spliced dem,As a new user of gmt, if i want to get the kml file like the official website (display the merged dem file to Google Earth to verify that my merged dem is no problem), what should I do next? In addition, I Is there any problem with the command I just ran? If not, how should I correct it? I am looking forward to your reply.

Maybe it’s simpler if you download your grids from


Regarding kml production see