load_earth_relief: Add earth_relief_type explanation to docstrings
@@ -31,9 +31,11 @@ def load_earth_relief(
This module downloads the grids that can also be accessed by
passing in the file name **@**\ *earth_relief_type*\_\ *res*\[_\ *reg*] to
- any grid plotting/processing function. *res* is the grid resolution
- (see below), and *reg* is grid registration type (**p** for pixel
- registration or **g** for gridline registration).
+ any grid plotting/processing function. *earth_relief_type* is the GMT name
+ for the dataset. The available options are **earth_relief**\,
+ **earth_gebco**\, **earth_gebcosi**\, and **earth_synbath**\. *res* is the
+ grid resolution (see below), and *reg* is grid registration type
+ (**p** for pixel registration or **g** for gridline registration).
Refer to :gmt-datasets:`earth-relief.html` for more details about available
datasets, including version information and references.
