[gdal-dev] WKT to proj.4 - I'm complete lost!

["José Roberto Pereira Jr."]

Hi list!

I'm a newbie in geoprocessing and I need to transform a WKT 
representation to a proj.4. I found a example using proj utility:

+proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +units=m +nadgrids=@null +wktext +no_defs

but I don't understand nothing about! Someone could tell me some resource or help me for translate the following WKT to proj.4?

GEOGCS[
	"GCS_South_American_1969",
	DATUM[
		"D_South_American_1969",
		SPHEROID[
			"GRS_1967_Truncated",
			6378160.0,
			298.25
		]],
		PRIMEM[
			"Greenwich",
			0.0
		],
		UNIT[
			"Degree",
			0.0174532925199433
		]
]

Thanks for tips!!
José