Similan Island Information: Underwater geology
The monsoon play an important role in all apsects of life on the Similans. The monsoons always head in from the South West over the Andaman Sea. So The east coast is protected from the monsoons features powdery coral beaches, coral gardens of hard and soft corals which slope dramatically from the surface down to approximately 30-40 meters.
The base of these coral encrusted slopes is usually flat and forms a very nice transitional zone. The reefs are lush and teaming with life. Some very famous dive sites have been filmed and featured in many magazines and books – East of Eden, Breakfast Bend and Beacon reef are among the most famous. Because of this incredible ecosystem, you will find most of the great snorkleing sites are on the East coast.
Here, the most popular activity is drift diving along hard coral gardens while watching the reef inhabitants go about their business. At several sites, large coral bommies covered with soft corals and sea fans rise dramatically from the bottom. Here, the diving is easy and navigation simple, allowing each buddy pair to explore at their own pace.
The Western coast of the Similans is typified by large boulder sites with steep drops. This is incredibly scenic and makes for incredible encounters as this is where the Pelagics (ocean going fish) come in to hunt. Frequent sightings of Manta Rays, Sharks, Barracuda and many more species make this side famous. This side is more exposed to currents and makes for more exciting dives and snorkeling. There are virtually no beaches on the West Coast (Donald Duck Bay is the main exception the this rule).
If you enjoy watching and photographing small fish the Similans are unrivaled for the sheer numbers and varieties of tropicals. Nudibranchs, Ghost Pipefish, Frogfish and lots of other small things make this a heaven on earth. For the Big Fish enthusiast – We Frequently see Manta Rays, Leopard Sharks, Reef Sharks (Black-Tip, White-Tip, Grey), Several kinds of Rays, Napolean Wrasse, Bumphead Parrotfish and lots more besides… Don’t expect big fish action every dive, just enjoy the Similans for what they are famous for: Wild, unspoiled beaches, magnificent coral growth, prolific marine life, crystalline blue water and sensational underwater rock formations.