An Island with a Central LagoonIsle with a central lagoon
North America: Central America: Clipperton Island. There may be an albatross or seaplane landing in the lagoon.
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Nikumaroro location and geology
Picture 1: Nikumaroro is an island of the Phoenix Group. Situated to the southern part of the Ecuadorian Sea, in a line just above the Tokelau Islands to the northern part of Samoa. It is part of a range of volcanoes that include the Carondelet Reef in the southern part and a large sea mountain of similar size to Nikumaroro in the northern part.
Orona, Manra, McKean and Canton are located on a chain of volcanoes. It consists of a central lagoon, a peripheral land edge, an expansive plateau of reefs and a precipitous cliff into the seabed (Fig. 2). 5 km broad, built on the ridge of a U-boat volume that rises through 5000 meters of ditch.
There is a central lagoon, which is serviced by two sections on the lee side (southeast). It is relatively flat, not more than 5 meters in depth on general and covered with a reef and reef. The largest part of the lagoon shores has no beaches; a few brief sandbows around the northwestern end.
Often densely overgrown reefs fall directly into the lagoon or into a marshy foreland of limy mud, a mix of birds' excrement and eroded corals. The clearness of the waters differs according to the climate. In a 1978 exploratory study, the island was described as "a set of cementated reefs".
At both sides of the island, albeit upwind, there are in many places burrs or berm of reef debris directly behind the island, which are the result of storms. On the north-eastern side, the wind side is a sand strip about 20 to 40 metres in width, which varies with the tides.
On the south-western side of the island, usually downwind, the main burden of the periodical heavy winds comes from the south-west and north-west. At some places the often strongly covered corals fall directly on the corals, at other places there are some smaller, more steep and rocky sandy reefs than on the upwind side, usually made of finger-sized corals blended with sands.
Outside the land edge there is an extended 200-250 meter long isthmus. At the top of the shore, the coral shallow water is covered by a typically geomorphous sequence of characteristics (Fig. 3). Figure 3: General Nikumaroro Geo-Morphology showing the most important characteristics of reefs, edges and lagoons.
A " canal " along the inner rim of the coral cliffs or due to the lack of one. A more or less shallow, coral-red coating, which often has a pock-like superficiality and is interspersed with cracks and stress gaps, is located on the seaward side of the canal.
It has a smooth surfacing with the growing Porolithon lime alga, which has to be cleaned every day with sea water to preserve it. There is a "tail and groove" area on the outside rim of the coral wall (Fig. 5). It is a steep-walled, narrower channel, usually several meters in depth, which begins at the edges of the coral and stretches in a vertical line to the edges of the coral and back to the bank as a shallow and tapered slit.
Rills are formed in the high pressure windsurfing area and serve as channels to channelize the waters flowing off the area. Usually the channels are arranged at distances of 20 to 50 metres and can retreat up to 50 metres into the corrugation. Figure 5: Photograph of a grooved section that tapers back into the roadway.
The waterslides act as waterslides that direct the waters onto the coral wall and as draining channels for the waters that flow back into the sea from the interposed tidal flat. Intermediate spores are more plate-shaped to slightly curved than round, but have a good enough tread to release excess seawater from the area.
Just like the shallow coral shelf, the end faces and even the grooved wall are coated with slick porolithon seaweed. There are large rocks on the coral and spore area. They were demolished and raised by means of hamming shafts under the overhang of the edges of the riff.
Behind the ridge is the precipitous descent area. Nonetheless, the terrain is far from slippery, as the rocky outcrops and cliffs that mirror the Pletistocene seabed are still there. Beneath this deep, the sides of the vulcano are probably clad in a staggering coat of materials, from sandy and gravelly to rocky and bouldery areas.
It is not flat, but rather grooved, with large burrs and steep canyons. Harry Maude remarked in 1937 that "the lush greenery on Gardner Island gave her the impression of having several low mounds from the sea". The Bukas are imposing up to 20 metres high and have a baldachin that extends within a 8 metre range from the thick, grey debarked bark.
In the north-west are large Buka populations with a border that runs down the small country behind the meander. In 1937, according to Maude, the island sponsored "some delicate canawa ("Cordia subcordata") groves". There was a large forest in the area known as the "Kanawa Point", and others may have evolved on the north-eastern side of the lagoon in the countryside known as Taraea.
Canawa seems to have been entirely evacuated from the island, neither we nor a flora commission of inquiry that came to the island in 1978 found any of them. Today Buchas are seriously overcrowded by imported palmos. Wherever the bucas have not been grubbed up to make room for planting evergreens, wild grape seedlings have been raised on the edge of the buca sites, competing with native plants for food and nutrients.
"The Te mao" (Scaevola sp.) is also a main rival and a great obstacle to people travelling on the island. It is easy to slice with a machete when still young, but when it' s dried, it can withstand non-mechanised people. It tends to concentrate along the oceans and lagoons, but can expand up to 50 or more metres into the interior, so that cover on smaller parts of the island is practically constant.
There are other herbs on the island such as a small shrub named "non" (Morinda citrifolia), a shrub named caura (Sida fallax) and a crawler named by the name of Portulaca sp. Today the only remaining species of the island are (as far as we know) quite large numbers of cats. Native land animal can be divided into three broadly definable functional categories: crayfish, bird and insects/Arachnid.
The crustaceans are coconut or predatory crayfish ( "Birgus latro"), other crayfish ( "Coenobitidae") and smaller coastal crayfish ( "Gelasimus"). A large number of very small recluse crustaceans certainly represents the youthful stadiums of Birgus Latin, but there are also many bigger recluse crustaceans. Fishes are grouper, trevally, barracuda, black tip sharks and white tip sharks, gray reef sharks and a multitude of other deep sea and deep canals.
The lagoon is home to many small fish. However, since some of the details of Earhart and Noonan's characters and behaviour are okay, it is possible that they may have had a role in their deaths. Birgus Latin, also called big cats, is a close relative of the crayfish.
Birgus is supposed to be able to rip the peel off the walnuts, perforate their tough inner peels and then break them open to remove the flesh, but we cannot find any publicised backing for this name. However, there is ample proof, among our own observation, that omnivorous animals are omnivorous and flesh consuming crab.
They are lonely, although in some places they are so abundant that they appear sociable. When they copulate on dry ground, the female go to the bank, where they discharge their nymphs into the sea. These adolescent shell-bearing phases continue until a shrimp is about two years old, with a shell about two to three centimetres in diameter.
For over forty years now, there have been numerous species of crab. They are digging caverns where they can mollusc. BURROW's can be complex tunnels ending in cavities, usually no more than 50 cm below the ground. It has been seen that shrimps stay in their caves for up to sixteen consecutive week, throwing off the old skeleton and curing the new one.
Nikumaroro has an abundance of crab coconuts. They called Niue Islanders, who worked on the island in the latter part of the nineteenth centuary, Motu Aonga - the country of shrimps of coconuts, and in 1937 a group of I Kiribati and English discoverers set fire in a ring around their campsite - "as a shelter from the huge predatory shrimps strutting around in twilight or hanging to the twigs that were wickedly looking at us.
The walls, apparently originating in the early Holocene (10ky), gave the island a mass terraced rock nucleus (above the present ocean level) that washed over or over sedimentary mass. In turn, these deposits become more beach rocks, as Ca-saturated ground water from the lagoon penetrates them and cements the particulates together. Atolls that are able to do this seem to have a solid nucleus, while others that don't have beach skirts don't (e.g. Carondelet Reef).
" The approx. 6 km long and up to 2 km wide tunnel with a surface area of 4.1 km² creates an oblong construction that encloses a small lagoon. Notice that neither pass intersects the wide plane of atolls. Most of the country is densely overgrown with Pisonia grandiis, Cordia uncordata and Cocus nutifier.
As all Rawaki Islands, the northern, southern and easterly sides of the island are affected by strong waves and are subject to windstorms and Pacific waves from the southern and easterly sides (note the width of the windsurfing line around three sides of the island in the picture).