Down but not Out Trivia Quiz

Answer: An area which is surrounded by higher land such that any water flows into its low point, but does not drain out to the ocean.

An endorheic basin is an area within which all water flows inward and there is no surface outlet. The term comes from "endon", meaning in, inward or within and "rhein", meaning to flow (Greek). Generally water loss within one of these areas is via evaporation, but in some cases (the Irish turloughs are a good example), water can seep out of the basin through bedrock.

In many cases there are lakes at the bottom of endorheic basins, but not always. When present, a lake at the bottom of an endorheic basin is called an endorheic lake and will have no outlet.

The Great Divide Basin in the United States is a good example of an endorheic basin without a lake.

Answer: The Dead Sea

The Dead Sea is located on the border of Jordan and Israel and is the deepest of the hypersaline lakes in the world. The Jordan River flows into this lake, but the only outlet from this lake is via evaporation, leading to the gradual accumulation of salt. Neither Lake Superior nor Lake Baikal are located in endorheic basins.

The Great Salt Lake is in the United States and is a remnant of Ancient Lake Bonneville.

Answer: Rahasane Turlough

Now you see them. Now you don't! Turloughs are indeed special endorheic lakes. They don't have an inlet or an apparent outlet, so that they are filled only intermittently. Turloughs form on the top of karst regions (area with bedrock consisting of limestone) and drain into small cracks in the limestone often leaving the small endorheic basins dry. On the other hand, they also appear to flood from the limestone as well. No one seems to really know what causes the flooding when it happens. Joe Ney's Slough (a wet marshy area) is located in Oregon (USA). Pant-y-Llyn is the only turlough not located in Ireland.

It is located in Wales. Loch Lomond is a lake, located in Scotland that has an outlet to the River Clyde, and from there to the ocean.

Answer: The Lasithi Plateau

Plateau? Basin? I guess it all depends on your perspective. This plateau is surrounded by higher land all around, making it a basin - so in this case it is both. It has been settled since Neolithic times and is extremely fertile. In this case, the water table is fairly high in the region because the bedrock underneath is impermeable.

Despite the high water table, there is no surface water outlet from this endorheic basin. The Tibetan plateau is in Asia, and as far as I know is not endorheic.

The Intermountain West is located between the Cascade Mountains and the Rocky Mountains in North America. The Hardangervidda is the largest plateau in Europe and is located in Norway. It is not endorheic, as water can flow off the plateau.

Answer: Lake Eyre

Lake Eyre is the largest lake in Australia when present, and also has no outlet. Lake Eyre is located at the lowest point of the Lake Eyre basin - an endorheic basin. The Lake Eyre basin covers a large portion of Australia and contains several intermittent river systems, as well as two deserts. Lake Bronte is my invention and doesn't exist. Lake George is another endorheic lake in Australia, and Blue Lake is a non-endorheic lake in Australia.

Answer: Crater Lake

Crater Lake is located on the top of Mt. Mazama, a volcano located in the Cascade Range in Oregon, USA. It is the deepest lake in the United States, beating out Lake Superior. Crater Lake is not saline, because it is filled only by precipitation. Evaporation of the water in the lake is precisely balanced with precipitation into the lake, so it tends to stay at a consistent depth.

The crater of Mount Mazama, surrounding Crater Lake forms a tiny endorheic basin, of which Crater Lake is the lowest point. Masa Crater in Japan is another endorheic lake on the island of Hokkaido. Lake Tahoe is located on the border of California and Nevada in the United States. Upper Klamath Lake is another Lake in Oregon and not endorheic.

Answer: The Altiplano

The Altiplano consists of a series of endorheic basins and contains Lake Titicaca and Lake Poopo both. Alti means high and plano, a plain and this is both, being at an average of 3,750 m (12,300 ft.). The climate is dry and cool. Lake Titicaca is located in this region and is considered to be the highest commercially navigable lake in the world. Lake Poopo (now dry) was contained in this region and was the lake into which Lake Titicaca drained. Peru, Chile, Argentina and Bolivia all claim portions of the Altiplano, with Bolivia claiming the largest portion.

The Columbian Basin is located in the United States and is not endorheic, as it is drained by the Columbia River, which flows to the Pacific Ocean.

Answer: Don Juan Pond

No, the Dead Sea is not the saltiest body of water in the world. The honors go to Don Juan Pond in Antarctica. This tiny body of water is also located in one of the driest regions of the world - the McMurdo Dry Valleys. This pond is interesting because it is not fed by any river or spring (in fact, it is similar to a turlough).

While the surrounding mountains prevent water from flowing out, they also prevent glaciers from flowing in and covering the valleys, which is why they are dry. The Great Salt Lake, while saline, is not as salty as Don Juan Pond and is located within the United States. Lake Whillans, rather than being endorheic, is an active lake located under the Antarctic ice and containing microbial life which exists without light.

Answer: The Caspian Sea

The Caspian sea is actually a very large saline lake. Despite being salty, the Caspian sea is only 1/3 as salty as the oceans to which it doesn't drain. The Caspian Sea has no outlet and water only leaves the region through evaporation. The Caspian Sea has many rivers that feed into it. Of these rivers, the Volga is the largest. Because it is so large, evaporation and precipitation from the Caspian Sea sustains a unique ecosystem within the basin surrounding it and much of the region directly surrounding it is quite humid.

The Salton Sea is located in the United States and is an artificially constructed shallow lake. The Sargasso Sea is an area in the Atlantic Ocean, which is defined by ocean currents only. It is named after the sargassum seaweed that floats to the surface in the area.

The Sea of Tranquility is located on the moon.

Answer: The Great Divide Basin

The Great Divide Basin is located in an area in the United States where the continental divide actually splits, creating an endorheic basin with lots of interesting features. One of the especially interesting features is that this basin is formed from many sub-basins and because of this, no one really knows which ridges, dividing these basins, are the continental divides. So there could actually be multitudes of divides in this area, each one of them a continental divide. Areas such as the Great Divide Basin may seem lifeless to those of you from areas with water and greenery, but there is plenty of life here -- including a herd of desert elk.