Facts about Marine Sediments Slump Deposits

Marine slump deposits are masses of coherent material that have been deposited along a ridge or geographical formation. These slumps are often the product of seismic activity, as well as heating and cooling that results in geologic distortions. Slumps often have distinct geologic markers, including specific formations depending upon the causes, as well as their age. They can be indicators of past seismic activity and geological history, and their formation can also be destructive in the form of slump-induced tsunami.

Marine slumps are deposits of materials that have usually broken apart from a larger mass. They are categorized as a coherent mass of materials that still has some geographic stability. Oftentimes they are found along ridges under lakes and oceans and are the result of earthquakes. They form essentially when the slope supporting their mass is distorted by global activity and they collapse upon themselves. Due to the way this would occur slumps that are caused by seismic activity normally fall over upon themselves and break into large, fragmented debris fields. Repeated seismic activity in an area can also cause multiple slumps that can yield data regarding the interval of time between events.

When slumps are caused by the forces of heating and cooling, their normal result is a much larger field than what is caused by a slump and is often called a debris field. These are marked by the material’s incoherent form, as if it has completely changed mass. In cases of extreme heating, the materials may look as if they have been completely melted down and have run across the surface. These deposits are different from slumps in the way they are formed, in addition to the content of their debris fields, and are usually caused by cataclysmic events and times of great geologic change.

The formation of slumps can be quite destructive in its own right, however, and it can produce tsunamis and seiche waves following an event such as an earthquake. Seismic activity can cause extensive amounts of damage to the Earth’s surface, and these events can be tracked through time by studying the formation of slumps and their patterns of development. At Lake Lucerne in Switzerland, five separate paleoseismic events have been recorded by analyzing the formations of slumps in the area. Patterns that can be ascertained due to the re-occurrence of these events can also aid researchers in estimating the seismic stability of an area over time, useful information when determining the safety of an area chosen for habitation.