How Ice Needles Create Spontaneous Zen Gardens

Live Science

Some of the most breathtaking zen garden patterns on the planet owe their existence to an unlikely artist: thousands of tiny "ice needles."   Credit: Quan-Xing Liu of East China Normal University

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00:00In high-latitude permafrost environments and high-altitude mountains, there are a large

00:12number of mysterious regular surface patterning, also known as patterning, such as the Qinghai

00:19Tibet Plateau and other freezing regions in China.

00:24The Svalbard Islands in Norway in the Arctic and the Alpine regions in Ethiopia.

00:32The patterned ground is made up of different kinds of stones and soils.

00:36Some arranged in polygonal net, stone circles, and others in strapped spatial patterns.

00:45The origin of these regular patterns has long been puzzling scientists, but recently this

00:51enigma is starting to be solved.

00:57Scientists now attribute the spontaneous regular patterns to a process called spatial self-organization.

01:05In the periglacial environment, when scouring together with soil freezing thorn cycles are

01:11speculated to drive the aggregation and separation movements of granular particles in the soil,

01:19which eventually result in assorted spatial patterns of stones on the land surfaces.

01:32This idea has been sparked by theoretical and empirical studies in physics, chemistry, biology,

01:40and ecology.

01:41However, it is notoriously difficult to test this idea in the field.

01:46The geomorphological systems in cold regions often evolve at extremely slow rates, largely

01:54forbidden human observers to record the processes.

01:57Many existing numerical models have suggested that differential frost heave and radial expansion

02:05of the fine-grained soils can lead to the movement of surface particles to the margins of the plugs

02:11and the formation of the self-organized patterns.

02:15This mechanism can reproduce a variety of large-scale sorted patterns, such as polygons and sorted circles.

02:24But direct experimental evidence for this model is still lacking.

02:28Scientists have long speculated that needle eyes formed in the permaforous layer could play a role.

02:35A new research led by an international team from China, Japan, the US, and the Netherlands revisited this old idea

02:45with brand new evidence and theory.

02:47The researchers designed an elegant experiment system that allows for the formation of needle eyes

02:55in well-controlled lab conditions.

02:57This system can mimic a time machine with which the observers can push the fast-forward button

03:04to speed up the process of land surface evolution within a microcosm.

03:09Within a couple of weeks, the researchers can now observe the years or even decades-long process happening in nature.

03:18They use video camera and computer program to automatically track the movement trajectory of every single stone

03:26and reproduce such observed processes in computer with mathematical models.

03:31The researchers found that, driven by the freezing thong cycles in soils,

03:36the surface granular particles migrated towards the stone-rich areas from stone-poor areas.

03:42This is exactly the process where a variety of order spatial patterns of stones arises from.

03:50This group of scientists have replicated the experiment numerous times,

03:55with all kinds of settings of needle eyes properties and stone field concentration.

04:00They put together these nonlinear relationships between different needle eyes height and stone field concentration

04:07to demonstrate that the geomorphological pattern formation process has the same physical principle,

04:13as that underpins the water-oil separation process.

04:16This type of activity is the shape of the stone-poor area from the stone-poor area from the stone-poor area to the stone-poor area.

04:26Known as phase-separation mechanism, the phase-separation theory perfectly reproduced the different types of sorted patterns,

04:34and found that the activity of needle eyes plays a dominant role in shaping this pattern ground.

04:40What makes the scientists more exciting is that their phase separation model can also

04:47perfectly reproduce the similar sorted patterns found in the Martian boulders by curiosity.

04:54Can this be seen as another evidence, reinforcing the existence of soil water on Mars?

05:00Just this mean freezing thong cycles also drive the evolution of Martian landscapes.

05:06Still too early to answer this question, but this study does open many opportunities to

05:12look into geological and geomorphic evolution of Earth-like planets.

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