What is Solifluction?
When Water logs, Soil Flows, and this mechanism is what we call Solifluction. That said, Solifluction is a term used for the slow downhill flow of soil in regions of the Arctic Ocean. It takes place slowly and is computed in millimeters or centimeters per year. It approximately uniformly affects the entire thickness of the soil instead of amassing in certain areas. It totally results from the waterlogging of sediment instead of short-lived events of saturation from storm runoff.
When Does Solifluction Take Place?
Solifluction occurs during the summer season thaw when the water in the soil is trapped by frozen permafrost underneath it. This waterlogged alluvium moves down slope by gravity, supported along by freeze-and-defrost cycles that thrust the top of the soil outward from the slope (a process of frost heave).
How to Determine Solifluction?
The major indication considered by geologists for solifluction in the landscape is hillsides that possess lobe-shaped slumps, same as small, thin earthflows. Other signs of identifying solifluction include patterned ground, signs of order in the stones and soils of alpine landscapes.
How Does a Landscape Affected By Solifluction Looks?
What is solifluction must now be clear to you. But do you know how a landscape affected by solifluction looks? It looks the same as the bumpy ground yielded by substantial landsliding but appears more like fluid, like melted ice cream or molten/diluted cake frosting. The indications may subsist long after arctic atmospheric circumstances have changed, as in subarctic regions that were once glaciated in the Pleistocene ice ages. Solifluction is regarded as a periglacial process, as it only needs chronic freezing conditions instead of the permanent presence of ice bodies.
Is there a Difference Between Solifluction and Soil Creep?
Solifluction in geology is one of the forms of creep that happens either in high altitudes or in cold climates where the mass of the saturated rock waste comes down the slope.
Soil creep means the movement of the slow downslope of the superficial rocks. It is an ongoing process and also a surface phenomenon taking place on the slopes.
Changes in Solifluction Movement Rates
Various Research activities carried out at the site depleted substantially in recent years, because of the personnel changes. Besides this site, little is known about recent solifluction movement rates in other regions of the Austrian Alps. In addition, nothing is familiar about regional similarities or differences with respect to solifluction rates and respective drivers in Austria, since solifluction measurements have not been conducted earlier on at several sites distributed over a massive area at the same time.
Studied Landforms
All studied solifluction lobes were situated in the central part of the Hohe Tauern mountain, central Austria, in a 38 km (west–east) by 11 km (north–south) large-scale region.
Solifluction monitoring was carried out at five sites namely: Elisabeth Felsen (ELF), Fallbichl (FAB), north-east facing slope at the Hinteres Langtal cirque (HNE), See Schartl (SES), a south-west facing slope at the Hinteres Langtal cirque (HSW) and the selection of the 5 solifluction lobes was based on the following parameter:
Area-wise distribution of the studied solifluction landforms and thus, to a certain degree, a region-wide reflection of the central part of the Hohe Tauern mountain range.
the morphological proof that solifluction acted upon these slopes a minimum few times in the past
the plausibility during fieldwork to apply synergies with the permafrost and periglacial monitoring network set up at nine sites in the Niedere Tauern and Hohe Tauern mountain ranges
FAQs on Solifluction
1. What is solifluction as explained in geography?
Solifluction is a geomorphic process involving the slow, downslope movement of water-saturated soil and regolith. This phenomenon is a form of mass wasting that is particularly common in cold, periglacial or high-altitude alpine environments. The process is driven by gravity after the soil's active layer thaws and becomes saturated, losing its structural strength and flowing over a still-frozen or impermeable layer beneath.
2. What are some common examples of landforms caused by solifluction?
Solifluction creates several distinct landforms on hillsides. The most common examples include:
- Solifluction Lobes: These are tongue-shaped or rounded bulges of soil that form as the saturated mass moves downslope.
- Solifluction Sheets: When the movement is more uniform across a wide area, it forms a broad sheet of displaced material rather than distinct lobes.
- Terracettes: These are small, step-like features that create a terraced appearance on a slope, often formed by a series of small-scale solifluction movements.
3. How is solifluction different from soil creep?
While both are slow mass wasting processes, solifluction is a specific type of creep with key differences. Soil creep is a very slow, general downslope movement of soil influenced by various factors like wetting/drying and temperature changes in any climate. In contrast, solifluction is specifically driven by freeze-thaw cycles in cold climates. The melting of ice in the soil provides the excess water that acts as a lubricant, making solifluction generally faster than typical soil creep and confined to periglacial or alpine regions.
4. What environmental factors are most important for solifluction to occur?
For solifluction to happen, a specific combination of environmental factors is required. The most important conditions are:
- Climate: The region must experience repeated freeze-thaw cycles, typical of polar, subpolar, and high-altitude mountain environments.
- Soil & Water: There must be fine-grained material (like silt and clay) capable of holding significant amounts of water, and a source of water (from melting snow or ice) to saturate the soil.
- Impermeable Layer: A critical requirement is an impermeable layer beneath the saturated soil, which is usually permafrost or seasonally frozen ground. This layer prevents water from draining away.
- Slope: The process occurs on slopes, even those with a gentle gradient, as gravity is the ultimate driving force.
5. How are the terms solifluction and gelifluction related?
The terms solifluction and gelifluction are closely related but have a nuanced difference. Solifluction is the broader, original term for the slow flow of any water-saturated debris down a slope. Gelifluction, however, is a more specific term used to describe this flow when it occurs exclusively over a layer of permafrost (permanently frozen ground). In modern usage, many geographers use gelifluction to specify the process in permafrost environments, while solifluction can refer to soil flow over any impermeable layer, including seasonally frozen ground.
6. Is the process of solifluction considered fast or slow?
Solifluction is a slow mass movement process. Its movement is typically imperceptible on a day-to-day basis, often measured in just a few centimetres to a metre per year. While it is much slower than rapid events like landslides or mudflows, it is a persistent and powerful force in shaping landscapes in cold regions over long periods.
