This is my first ever map. I’m not sure how plausible it is, and I’d appreciate any feedback or advice on how to make it more plausible. I haven’t put names or anything on it yet because I want to be certain about my geographical features first.
Some clarification: This is a small part of the world, although it’s all I’m going to be exploring in the story. The top part is maybe a little lower than the equator and the rest extends into the Southern Hemisphere.
Thank you!
The N-S mountain range on the northern island is odd. I would expect it either to be old and trail off gradually into hills and lowlands, like the way the Appalachians in the eastern US trail off before reaching the Gulf of Mexico, or reach out into the sea as a peninsula, like the mountains of Hispaniola (Haiti + Dominican Republic).
You have an ocean-trench/mountain range combination on the north shore of the southern island. I expect that's meant to be a subduction zone. Those are usually quite large, continent scale, like the entire coast of South America or the Japanese archipelago + Kamchatka. If your island is meant to be that big, you might need to draw in some more terrain variety, instead of just one forest and one swamp on each continent.
You've labelled them as volcanic, which is fine, and it kind of looks like they're meant to connect with the small "volcanic islands" archipelago. That would look a bit more realistic if you connected them a bit more, like the way the Aleutian Islands trail away from the mainland.
"I’d appreciate any ... advice on how to make it more plausible". Starting from an existing map (which could be better but is not bad) climate and biomes are the main outstanding issues that need to be addressed. You need to look at latitudinal climate zones and the Hadley circulation cells that make them what they are. Consider the magnitude and effect of Coriolis on your planetary weather systems. Also consider orographic rainfall and the consequent rain shadow effect. Lastly you need to work out oceanic circulation and the areas where unusually warm or cool surface water will effect the weather. These factors combine to give you a good idea of the dominant biomes that should naturally occur in different areas and you can then be realistic about how these will be disrupted/altered by the activity of humans or similar.
For greater realism in future projects you may wish to start by looking at your planet's geology as a guide to its geography.
Personally, I don't think your map is "bad". You've made a pretty good start at creating a world. I must agree, however, that having two nearby mountain ranges at a 90 degree angle does seem geographically unlikely *unless there was a reason for it in the story)
I kind of like the idea that on the larger body of land, the mountains completely cut off one part of the land from another. That immediately makes me think of a world with very different, isolated societies who will... one day... have to meet, or a place where a deep dark secret is hidden. I kind of like those giant mountains, but I do think I would draw them so that they descend into (or rise up out of) the ocean. If you think about it, would you expect a gigantic set of mountains to suddenly end at the shore?
Another point: someone mentioned "scale" in one of the comments, and you yourself are asking for "plausibility". I would say that plausibility is only required if it drives the story forward. A rough hand-drawn map might be part of a story line. Remember: Story line is everything!
Keep up the creative work, and good luck!
Undeniably the best way to create a world map is to actually copy an existing realistic world map, that's how I developed my world map and that's what I highly recommend you do. Study as many maps and images you can find, then mix and match whatever you find appealing and useful.
As far as your current map goes, it's a decent start but it's got a long way to go. The main rule you have to keep in mind is that nature doesn't work in straight lines. Rivers tend to originate from mountains or lakes and wobble their way seemingly all over the place before streaming into another water mass, mountains tend to form arches rather than straight belts from their extreme ends. Oceans and mountains rarely meet but that can be a possibility if you're willing to suspend your disbelief just a bit but if you don't use this effect sparingly your map will lose credibility in the realistic department (meaning you apply this only when you really need to slam an impassible barrier in a certain area). Shorelines are very rarely a clear-cut thing and, most often then not, they're broken up with lagoons, deltas or minor island formations. Archipelagos are also a thing and no map containing vast amounts of water should ever be without at least a few. Forests are at their thickest near water masses and they're also sprinkled all over the place, which means you shouldn't ever have a broad stroke of area that's either completely covered in forests or completely lacking in them (unless you're dealing with named jungles or deserts then it's ok).
