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The [geomorphology] tag concerns the landforms and exogenous processes of the surface of the Earth or other solid surface planets.

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Why are the mountains predominately grey or dark brown?

Observing many photos of mountains one can assume that most of the mountains are grey or brown. See also the mountain article at Wikipedia. There are however several ways a mountain can form, which ...
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How are the Scala dei Turchi staircases formed?

The Scala dei Turchi i (Italian: "Stair of the Turks") is a rocky cliff on the coast of Realmonte in Italy: https://en.wikipedia.org/wiki/Scala_dei_Turchi#/media/File:Scala_dei_Turchi_panorama.jpg ...
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How old are Chile's fjords?

Do we have any knowledge about the age of Chile's fjords, more specifically, those found near the Northern Patagonian Ice Field? Is it reasonable to conclude that they were formed in Quaternary given ...
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Subterranean Climate System?

Do subterranean habitat have climate system(s)? Could it be placed in any or all of the known ones: tropical, subtropical, temperate etc. ? Is it unique?
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What separates the Karakoram Range, the Hindu Kush, and the Himalayan Range?

In Google Maps, I don't see any boundary between the Karakoram (a.k.a. Karakorum) Range, the Hindu Kush, and the Himalayan Range. What separates these ranges?
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Natural spiral pattern of grass - what could cause this?

During a nature walk inside an old abandoned quarry I stumbled upon strange spirals that appear to be naturally formed. What could cause this spiral formation? Is it a known phenomena? To clarify , ...
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How are giant sinkholes filled up?

There are a few impressive photographs of giant sinkholes that appeared in cities, such as this one: However, followup information (e.g. Guatemalan sinkhole) or photographs on how these kind of ...
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What factors make Lake Turkana a great location for preserving fossils?

I am trying to figure out why Lake Turkana has yielded so many hominin fossils compared to other locations in the East African Rift Valley. One of the reasons is possibly the laying of sedimentary ...
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What produces these distinct shapes in the Rub' al Khali seen from space?

update: Searching "Rub' al Khali Empty Quarter" found "Q2: What are sabkhas?" in https://www.geocaching.com/geocache/GC6BYQ0_rub-al-khali-the-empty-quarter which seems to be related. From the NASA ...
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What causes these circular swirls of islands?

I was following the boarder of the US and Canada on Google Maps, because, and found these interesting circular patterns of islands near the Northwest Angle. I have heard of geologic folding but I have ...
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The grains of the parabolic dunes

My text book says that parabolic dunes consist of consolidated limestone grains, but I wondered if they have sand grains too, so I googled this issue and found that they consist of sands, but I am ...
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What causes jagged appearance of mountains in SE Asia?

For some time now, I've noticed that mountains in southeast Asia seem to be unusually "jagged" with steep surfaces. My basic knowledge of how mountains are formed (via geologic processes) tells me ...
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Esker vs. Kame vs. Drumlin - what's the difference?

In researching glacial features, I came across the terms esker, drumlin, and kame. I know that they are all depositional features that are shaped like a mound. My impression is that an esker is longer ...
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A circle shape in Madagascar

I was seeing Madagascar on Google Maps and accidentally i saw a circle shape near Bebao. Coordinates are 17.4317443°E and 44.644248°S. Please, to satisfy my curiosity, can you tell me why is this ...
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What, exactly, is angle of repose, and where is it in this image?

I'm a little mystified by "angle of repose" and the relationship to deposition and transport. In the following image, I detect 2 different angles of repose for the same material. How can this be? ...
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Is it possible to infer the depth of a river from the shapes of the islands and the banks?

Look at the photo below. Presumably, the river bed is a smooth shape. Therefore, it should be possible to infer the depth of the water from the photo, right? I am not even an amateur of geo-science. ...
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Identifying a desert landform

I saw this landform on Google Earth on the border of Algeria/Tunisia/Libya and wondered what it is called (so that I can read up on it and find out how it forms - I am not a geologist): Here is a 3D ...
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Strange craters in Afghanistan

In this image from 2004 in Afghanistan Kandahar region many small craters are seen. What are they?
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How much area in the world is under SemiArid climate?

I am studying the L.C. King's "Normal Cycle of Erosion". Apparently, he suggests that Davis was incorrect to have assumed Temperate Humid conditions as "normal conditions" of the world when ...
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Flooding lakes in geography

Came across the following problem on a question sheet. At its maximum level following deglaciation, approx 11,000 years ago, Lake Melville flooded the Sebaskachu River valley to an elevation of 135m ...
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What processes created these apparent topographical anomalies in North California?

In the attached topographical map, you can see some strong topographic features in Northern California — elongated foothills below Mt. Tamalpais. You can also see, circled, some apparent anomalies. ...
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Waves on sandy beach separating differently-sized rocks?

I recently went to a beach, and I noticed that the sand seemed to have a few distinct regions. I'm wondering what would cause this, and how it works. One region is the part of the beach which is ...
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What is Stock or Overflow Pit? Is it a terminology in geography? What is the correct word for it? [closed]

I have an excel file that I have to make the join with another table that has a column listed of different kind of feature types. This was done by someone else who did GPS'ed and spell that word and ...
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Could a massive flood have formed the Grand Canyon?

I believe that the accepted theory for how Arizona's Grand Canyon was formed was that erosion caused by the Colorado River flowing through the area over millions of years was the force at work. Yet ...
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What causes such a narrow slit in a cliff? (see photo)

I have this photo as a background image and I often wonder how such a narrow, well-defined slit could be formed. Is it natural or man-made? If natural, what processes could have formed it? The rest of ...
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What is this strange formation near Râmnicu Vâlcea?

So I was browsing Google Earth the other day and I found this strange formation near Râmnicu Vâlcea, at about 45°07'N 24°16'E It's an almost circular region, about 40 km in diameter which to my eyes ...
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What are 'articulate shells'?

I can not really find a definition, not even in a geologic dictionnary: What are articulate (resp. inarticulate) shells? To be more specific, the term is related to tsunami deposits (tsunamite).
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Dating fluvial terraces with $^{10}\rm{Be}$

I've completed part A of the question below. Dating fluvial terraces with $^{10}\rm{Be}$ One way to determine the age of an alluvial deposit is to collect a series of samples from a range of depths, ...
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Why doesn't the whole volcanic cone appear black?

Cooled lava looks black, but why the whole volcano, even near crater, doesn't always appear black like cooled lava?
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Impact craters under water

What would be the resulting impact crater of a meteorite hitting bodies of water on Earth? Let's take for example the impactor that resulted in Meteor Crater, Arizona. What would the impact look like ...
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Are craters on Earth covered by vegetation?

When you look at other planets and moons in our solar system most of them have lots of craters. If Earth had no vegetation and water would it also look like this image of Charon? Image Credit: NASA/...
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When does an island with isthmus become a peninsula?

I'm currently on holiday in Indonesia. In my travel guide I was reading about the island Samosir, which I'm visiting in a few days. I read that the island, which is located in lake Toba, is connected ...
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Why is Mauna Kea taller than the maximum height possible on Earth?

We can calculate the maximum possible height of the mountain on earth. If the elastic limit of a typical rock is $3 \times 10^8\ \mathrm{N/m}$ and its mean density is $3 \times 10^3\ \mathrm{kg/m^3}$,...
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How do long rivers exist?

I was recently on a long-haul flight over Siberia and it struck me as rather remarkable that something like the Lena River could exist. It seems very surprising that there's a route from some random ...
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What processes produced the basalt columns of the Giant's Causeway?

The Giant's Causeway is, according to the Wikipedia page was formed during during the Paleogene Period, Antrim was subject to intense volcanic activity, when highly fluid molten basalt intruded ...
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What is the purpose of this large structure on a Japanese hillside? [closed]

A Google satellite view shows an unusual structure on a hillside in Miyazaki Prefecture, Japan (Latitude 31.782600°N, Longitude 131.233881°E): It measures about 170m by 120m and is structured in ...
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How did sand dunes appear in the midst of a fertile region?

I recently visited a place called Talakad/Talakadu about 40 km from Mysore, India. Its an amazing place where a whole city has been covered by sand about 15 m deep. The local myth is that a curse ...
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How and why do these tree-like river structures form?

I noticed these detailed tree-like river structures in Google Earth Google Maps link How and why do these form? Rivers don't typically split. What would cause the water to keep branching off again ...
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What is the age of the Gamburtsev Mountains?

The mechanism for the formation of the Gamburtsev Subglacial Mountains in East Antarctica seems to be a combination of old volcanism and Cretaceous rifting (Ferraccioli et al., 2011). While the ...
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The river or the hills; which came first?

On the upper Mississippi in Illinois and southern Wisconsin, the river is bounded by hills and bluffs which define the outer edges of the flood plain. There are similar configurations for some of ...
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Geomorphology of Mountains With Wind only Erosion

I am curious what mountains would look like if erosion occurred almost entirely by wind. Specifically, I am curious of how granite mountains would look on a "snowball" terrestrial-sized xenoplanet. ...
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How are minor tributaries of a river determined?

What are the criteria to determine if river A is a major or minor tributary to another River B? Is stream order the only deciding factor i.e. the highest order is the main stem, one less order is a ...
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Why are most peninsulas oriented north-south?

Weird question, bear with me. Most large peninsula on Earth are oriented southwards (and most of the rest northwards), much fewer east or west. Some examples: Florida, Californa peninsula, Yucatan, ...
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What made the Grand Canyon the “greatest” canyon in the world [closed]

The Grand Canyon is nearly 446 km (300 miles) long, 29 km (18 miles) wide, and over 1,8 km (1 mile) deep. To the best of my knowledge, there is no other canyon of comparable size in the world. Is ...
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How deep was the Vredefort Crater when it happened?

The Vredefort Crater is one of the biggest known impact craters on earth. How deep would it have been, relative to the original ground height, immediately after the dust settled, and before any ...
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What is the origin of the Montmartre mountain in Paris?

I have always wondered what is the origin of Montmartre mountain in Paris. What surprises me is that the whole area seems quite flat, and yet there's a very steep hill in the middle. How has that ...
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How do we measure the total amount of variation in height of Earth's topography?

Could it be measured by taking the Laplacian over all tiles and then averaging it, for example? (this question can be relevant for both surface topography and ocean bathymetry). I think measuring it ...