Origins of the Dead Sea, Part VII: Mt. Sodom – A Huge Pile Salt

Rising out of the plain at the south end of the Dead Sea Valley is a billion-ton mountain of salt.  An eight-mile long, three-mile wide, 742-foot tall (above Dead Sea level) mountain protruding from the basin plain.

This is Mt. Sodom.

This mountain is composed almost entirely of halite also known as rock salt.    Over time, rainfall and groundwater has eroded the parts of the mountain, creating numerous caverns in the salt dome.  Many of those caverns have been occupied by humans long ago, including (possibly) Lot as he fled the destruction of Sodom and Gomorrah.  They may have also been a temporary refuge for David while running from King Saul.   The evidence of thousands of years of ancient habitation in these caves tells us that despite its susceptibility to melting, this mountain of salt has not changed much throughout recorded history.

So where did this pile of salt come from?

Massive Sediment Deposits Lie Under the Dead Sea Valley Floor

In this series (see sidebar for links to other parts of this series), I have mentioned that the Dead Sea rift is very deep.  The rift of ancient rocks that once formed a continuous set of strata is now filled with 15,000 feet or more of sediments, most of which have turned to rock.  What are the characteristics of these sediments and rock?

Some of that rock is rock salt (or halite), but much of it consists of thousands of layers of alternating aragonite (calcium carbonate), magnesium sulfate, gypsum (calcium sulphate) and other salts, along with bands of silicon-rich sediments derived from the erosion of rocks from the surrounding mountains.

The composition of these rock layers is best understood as the result of the continuous existence of a hypersaline body of water like the Dead Sea present in the Jordan Valley for hundreds of thousands of years.

Today, sediments and salts are brought by water to this terminal basin, and the salts precipitate out of the water and fall to the floor of the lake.  Distinct forms of salt (e.g., halite, aragonite) is formed because they precipitate at specific concentrations.  So the amount of evaporation and fresh water input into the sea dictates how layers of material will be laid down on the floor of the Dead Sea.  Those layers have been forming one on top of another reaching 10s of thousands of feet thick.

Mount Sodom:  A Massive Pillar of Salt

Numerous research projects have been undertaken to explore the origins of this huge, three-mile long mound of salt.  For example, ground-penetrating radar has been employed to “see” 20,000 feet of rock layers below the Dead Sea.  This revealed that the roots of Mount Sodom are found in a thick layer of nearly pure halite buried under nearly 10,000 feet of sediments and rock.  This thick halite layer represents a time in the early history of the Dead Sea rift when there was a periodic connection to the Mediterranean Sea.  Previously we saw that this past connection with the Mediterranean allowed salty ocean water to flow into Dead Sea Valley where water evaporated and salts fell to the bottom of this ancient lake.  Later, after becoming disconnected from its sea salt source, layers of sediments and other salt were deposited on top of this salt later.

This rock salt is not as strong or dense as other type of rock.  As more and more sediments were deposited on top of the salt, the weight of this overlying material squeezed the halite up through the rock above, until it pushed out above the surface.  The typical analogy given is that of soft mud that rises to the surface when heavier material is put into a bucket. The heavier material displaces the lighter, weaker material. These “salt domes,” called diapirs, are found in many parts of the world.

Squeezing a thick layer of pure salt up through 10,000 feet of rock is no small task and doesn’t happen overnight.  Given the distance the salt has moved and the physical constraints on salt crystal deformation Mount Sodom is likely hundreds of thousands of years in the making. 

There are other smaller salt domes that still lie buried under the sediments of the Jordan Valley that are still working their way up to the surface. Someday, they will form new salt mountains.

With modern technology, we can confirm that Mount Sodom continues to be squeezed out of the ground today.  Satellites show that Mount Sodom rises by a rate of around 3.5 mm per year, despite the general subsidence of the land around it.

Biblical timeline and Mt. Sodom

As I suggested, Mt. Sodom likely appears today much as it has during the time of the earliest recorded residents in this region.  Thus the origin of this mountain, like the Dead Sea, must predate at least the time of Abraham.

The geological studies of Mount Sodom tell us that ever since its origin, the region has been exceptionally dry.  Why? Because had there been a time when the climate of the Middle East was much wetter, this mountain would have eroded to a far greater extent than it has today.

The features of the Dead Sea valley, both geological and climatological, conform well to the observations made in the Bible.  The Bible doesn’t tell us anything about how the valley itself originated, but strict 6-day creationists—with their interpretation of Noah’s flood as both a global and geologically transformative event—are forced to conclude that Mount Sodom originated after a global flood, from sediments that the flood deposited.

In addition to the obvious lack of any mechanism to explain why nearly pure rock salt should be laid down in the middle of a global flood, Mount Sodom provides nothing but difficulties for young earth creationists.  For these YECs, Mount Sodom’s formation and the formation of its caves must be shoehorned into the very short period of time between the end of the flood (4500 years ago) and the construction of the cities of Sodom and Gomorrah, which predate even the arrival of Abraham to the region.

Translation: if you believe a young-earth timeline, your hypothesis is that Mount Sodom formed over a period of no more than five hundred years.

I used the term “shoehorn” because the data must be wedged unnaturally into this young earth interpretative framework.  None of the data would be interpreted this way without a presupposition of a young earth.

The layers of salt and sediments, the real-time data proving on-going uplift of Mt. Sodom, the slow erosion of caves in a dry climate–all of these point to processes that have been ongoing for hundreds of thousands of years.  These processes have little or no impact on the historical accuracy of Scripture, unless we assume a global flood occurred 4500 years ago.

But, as we have seen in this series, even if we could bring ourselves to consider that such an event happened, we have plenty of geological and biblical data that should make us doubt the global-flood premise.