Back-reef

Figure 6.9. Mean concentrations of dissolved species in Checker Reef pore waters and overlying seawater. Vertical bars indicate standard deviations. "FR" and "BK" refer to seawater samples from the fore and back reef stations. Other symbols refer to l-and-2 meter deep sampling stations across the reef (D is the midpoint of the reef). (After Sansone et al., 1990.)...

Gregg, J.M. Shelton, K.L. (1990) Dolomitization and dolomite neomorphism in the back reef of the Bonneterre and Davis Formations (Cambrian), southeastern Missouri. J. sediment. Petrol., 60, 549-562. 

Where the waves and currents weaken, resuspended sediment settles back down to the seafloor. Given the small particle sizes of the suspended material (mostly 3 to 10 pm), redeposition can take many years. The resulting redistribution of sediments creates patches of clay, mud, and exposed rock on the continental margins. In other words, resuspension from waves and currents can cause some sediments to become reUct deposits. Hard bottoms can serve as good habitats for some members of the benthos as they promote the formation of coral reefs. For paleoceanographers, relict deposits are problematic because they represent gaps, or imconformities, in the sedimentary record. 

The Tuamotus. The trade in reef fish between the Tuamotus, atolls north of the Society Islands in French Polynesia, and Tahiti, may be the most extensively developed export of reef fish at the local level threatened by cigatoxicity. Over 60% of the entire population of French Polynesia resides on Tahiti and the majority in the Papeete urban zone. Due to overfishing and environmental change associated with population increase, the resources around the island of Tahiti are depleted. In 1976 49% of the fish sold in the Papeete market was from the Tuamotus. Trade links between the two island groups go back to the trade in stone axes in precontact times and continue... 

John and Kate were visiting the Great Barrier Reef for the first time. When their boat arrived at the reef they decided to go snorkelling straight away so they could see what the reef was really like. Kate was not as strong a swimmer as John and got tired. She found a place on the reef where she could stand on the coral and have a rest. John was a strong swimmer and he found a place where there were many different types of coral. He very carefully touched some to see if they were as different as they looked. After a while both Kate and John went back to the boat for lunch. They threw their orange peels into the ocean. 

Back W., Hanshaw B.B., Herman J.S., and Van Driel J.N. (1986) Differential dissolution of a Pleistocene reef in the ground-water mixing zone of coastal Yucatan, Mexico. Geology 14, 137-140. 

At the bottom, three Caribbean reef sharks approached. I pointed to the biggest one and signaled Tim to swim close to it so I could get a picture. Without a moment s hesitation, he took off after the shatk into deep water. As he herded it back towards me, I could tell by the gleam in his eye that he was deciding where on his hide he was going to immortalize the scene. 

Before starting with the systematic study on the hydraulic performance of this new reef concept, it was important to demonstrate first its efficiency with respect to the protection against beach erosion. For this purpose, a submerged two-filter system with porosities e = 11% (front screen) and e = 5% (back screen), spacing B = 10.3 m and height = 4m was installed in front of a beach profile. The same... 

These people had been intercepted or towed back into Indonesian water by the Australian navy. Some had successfully landed on Australian soil in Ashmore Reef, but were forcibly removed by the Australian forces. Conditions were atrocious in Indonesian camps with stories of children, men, and women on hunger strikes. On... 

The eastern coast is inaccessible, with high rocky land, and at intervals there are openings. The bay we had to cross, which begins at Concepcion, is all surrounded and shut in with islets and reefs. We arrived at the back of the land where we had taken the Indian who escaped from us, and found that it was an island. We named it the island of San Francisco and, within the channel, between it and the land to the east, there are six islets and rocks at the mouth. We passed the night at this island of San Francisco. 

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