How do Glaciers Form and Move?

Ice fields such as glaciers have for ages locked the world's history's secret in their body and possess the capability to reshape its destiny. This book will cover in detail the processes of glacier formation and movement, unveiling the secrets that lie beneath their icy surface.

What are Glaciers?

Basically, glaciers are huge acreage covered by ice, which is produced after long years of snowfall with deposition on the ice. These icy giants occur in various forms mainly as ice sheets covering entire continents and smaller glaciers snugly located within the alpine valleys.

Glacier Formation

Everything really starts with such a one, a snowflake. A thick snow cover is ultimately formed, and this will start to pile up, one layer at a time. Due to the increasing weight of the subsequent snowfalls, the denser layers form below the surface and, eventually, the lower ones are transformed into a compact firn.

Compaction and Recrystallization

The air that firn contains is squeezed out and pushed further inward by the the weight of the overlying snowpack. The process associated with the formation of glacial ice is achieved through this additional pressure. Recrystallization is a way by which the individual ice crystals within a glacier realign, resulting in an ice mass of be fixed in place.

Flow and Movement

Though they look like big, solid rocks, glaciers are actually in a state of continuous motion. The strength of gravity, the whole weight of the glacier, makes it move like a flow, it creates a lot of valleys and shapes the region also when moving.

Factors Influencing Glacier Movement

Gravity

Gravity in fact has a very strong leading role in the motion of glaciers. The massive glacier presses harder into the ground than the bedrock can withstand. Therefore, it begins to flow down the slope, following the path of least resistance.

Internal Deformation

Beneath the glacier, deformation of ice crystals results from a compression caused by the overlapping ice layers. Unlike fluids, those crystals are able to flow in a similar way. This changing shape of the ice, which is known as internal deformation, lets the glacier to heave over the terrain obstacles.

Basal Sliding

Besides internal deformation, glaciers also slide along their bedrock bottom, lubricated by a thin layer of water that forms from the pressure of the ice from above. The phenomenon known as basal sliding is thought to be capable of even doubling the speed of the slip of the glacier.

Types of Glacial Movement

Plastic Flow

At places that are thickly pacified and where slope is gentle, the ice is deformed and flows in a way that is similar to the viscous fluid. Such movement is called plastic flow and is the reason why the glacier goes down the hill.

Creep

On the glacier’s outer surface, the processes of creep occur individually, where the ice crystals deform and slide past each other under a high pressure. Though this constant tiny shuffle cannot be viewed by the naked eyes, it represents the flow of the glacier as a whole

Surges

Occasionally, the glacier movement may speed up suddenly, which is called a surge. These surges are caused by the peculiar phenomenon of water pressurizing the pockets of melted ice beneath the glacier, which then triggers its conditional slide and sudden advance in a moment's time.

Ultimately, glaciation and ice buildup and movements are a combination of physical parameters that act as control points and affect their shape. Whether it accumulates as snow, or relentlessly plows into the ground, each element plays its unique role in the sculpting of these large conglomerates. Through the complex dynamics of glaciers, we are able to get a good understanding of the constantly changing landscapes of our world.