Questions tagged [geomorphology]
The [geomorphology] tag concerns the landforms and exogenous processes of the surface of the Earth or other solid surface planets.
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Is there sand in Antarctica?
There's a song "Blizzard's Never Seen the Desert's Sand". Given Antarctica is a desert, someone questioned the title's validity. BUT is there sand in Antarctica?
I'd imagine yes as it's a pretty ...
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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 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 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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Why are deserts mostly located on the western side of continents?
I read somewhere in a book that mostly desert found in the western part of a continent. So my question is that why is it so? I searched on the internet but I didn't get a reasonable answer for that.
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What are these lake-like blue patches in the desert, visible in satellite image?
I found some blue patches in the Arabian desert in Google Earth. It looks like as if they were lakes with sand dunes rising out of the water. But there isn't water in the desert, at least not this ...
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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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How did this rock dome (pictured) form?
I saw this rock formation near Hveravellir, Iceland. It is probably of volcanic origin and looks like a dome. It is nearly symmetric and appears to consist of hardened lava maybe, with several very ...
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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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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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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 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 is this weird looking structure in Ethiopian desert?
I was surfing through Google Maps around Ethiopian desert region (close to the town of Werder/Wardheer) and I found this weird looking structure. It seems like a dried up lake bed, but I can't guess ...
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What causes these mound-like ground formations?
Whilst riding on Mam Tor in Castleton, England I came across this scene (not my photo) and I would like to know what causes the formations which I have ringed in red. They look like piles of earth ...
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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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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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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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Origin of Andaman and Nicobar islands
Are Andaman and Nicobar islands in Indian ocean a continuation of Alpide-Himalayan orogeny or are they volcanic in origin?
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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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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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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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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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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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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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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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What do you call boulders of non sedimentary rock that were lithified into sandstone?
I'm convinced there is a word for this. I was in the Hoodoos at Writing on Stone this weekend and kept noticing what looked like reddish quartzite boulders laying around in the sand, or sometimes ...
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Why does this shoreline change this way?
There are different reasons why a shoreline can change, including tides. But I've found a phenomenon that I can't explain.
It happens in a Mediterranean beach called L'Esparrelló/La Caleta (link to ...
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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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Is there a widely accepted reason for the formation of tafoni?
Expansion of tafoni seems to be based on weathering (seems reasonable enough.) But what creates them in the first place? There are a number of explanations online (Wikipedia lists eight plausible ...
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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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How did the Ural mountains form?
A nice picture for "how mountains formed" on Earth is due to the motion of tectonic plates. As the plates crash together, mountains may get "pushed upwards". However, a quick look at a map of the ...
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Similarities and differences between lava flows and fluvial geomorphology (rivers)
How are active lava flows similar to fluvial geomorphology? You can search youtube for these dramatic videos of lava flows, and they all seem to look very similar to streams or rivers. I know that the ...
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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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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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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 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 ...
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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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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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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 ...
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Geomorphological feature identification
I was studying a satellite map of Iceland and came across an interesting, but unnamed feature located between Vatnajökull glacier and Trölladyngja volcano (between 64°50'35"N, 17°11'21"W and 64°48'33"...
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What makes sand dunes shaped asymmetrically?
I have been working on a simulation to approximate the formation process of dunes. I understand that their formation is a result of saltation and aeolian processes, but I don't understand the exact ...
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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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Do lakes tend to have elliptical shapes more often than circular shapes?
I saw this interesting graphic (The World’s 25 Largest Lakes, Side by Side) of some of the largest lakes in the world.
It strikes me as somewhat curious that most of the lakes have a high eccentricity ...
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How does one get a steep-sided stratovolcano with extremely fluid, low-viscosity lava?
The shape of a volcano generally depends strongly on the viscosity of the molten rock used to make it:
If the magma/lava ("magva"?) is relatively fluid, it flows out gently, and you get a ...
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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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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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The geology of local landscapes and small scale features
I'm learning geology to understand the processes behind the formation of my local landscape.
I understand the processes behind big features, such as mountains. But I'm struggling to understand the ...
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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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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 is this geomorphological form?
What is this geomorphological form located at Vitrolles, France?
And how is it formed? It is like a 'raised flat land', or a base of a hill where the top 80% is cut, leaving only the wide, flat base.
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