Geologic terms are often used in everyday life as metaphors.  Some examples are: volcanic temper, a stress drop (after a major event), glacial pace, rock solid, etc.  In this post I will search for the origin and first uses of landslide as a geoscience metaphor.  First some definitions.

The term landslide, as far as I can tell, was first defined by Charles Lyell in “Principles of Geology” in 1830.  Lyell used the term “landslip” and not “landslide” and defined it as

A portion of land that has slid down in consequence of disturbance by an earthquake or from being undermined by water washing away the lower beds that supported it.

Principal components of a landslide are shown in this figure from the North Carolina Geological Survey .

The Wikipedia definition can be found here.  Here and here are examples of landslides from Romania, taken from the post on “Hazards and mud volcanoes in Romania”

The most common use of landslide as a metaphor is in politics; “won by a landslide” refers to capturing an overwhelming majority of votes by one party or candidate in an election.  First record I could find with this meaning is from a New York Times article from August 8, 1884 describing the Chicago’s Mayor Carter Harrison outlook on his chances for an upcoming election:

If it shall become reasonably clear in October that the Democratic Party will carry New York, New Jersey and Connecticut – and by October we shall know about where we stand – I shall look for the election of the Democratic Electoral ticket in Illinois by 10,000 majority – a perfect landslide in fact

Jacques Chirac’s victory in the French presidential election of 2002 by 82% is perhaps the best modern example of a landslide election.  In Romania’s historic election of 1990, Ion Iliescu, a former communist party official, won by a landslide and became the first post-communits president.

Politics also inspired two boardgames named “Landslide“, about the US presidential elections.  And of course there is also the music: Fleetwood Mac’s 1975 “Landslide” song remade in 1994 by the Smashing Pumpkins and later in 2002 by Dixie Chicks.

©EarthRelated

The Arches National Park in Utah is a must see. I was not too long ago in the Moab area for geology-related field work and stopped for a few hours in the park.  This was not my first visit, but I enjoyed it as much as the first time. Below is a short account of how, from a geologic point of view, the arches formed.

It started with a “see-of-sand” in Jurassic, about 200 million years ago; at that time the Moab area looked not unlike the Sahara.  The desert-like environment persisted for fifty million years or so, and resulted in the accumulation of the two sandstone formations that make the natural beauty of the Arches today: the Navajo and the Entrada.  These formations overly a layer of salt, three hundred million years old. The salt has the interesting property of moving when loaded with sediment, just like tooth-paste moves when loaded and squeezed from the tube. Imagine a brittle layer of sandstone pushed up by a mobile layer of salt from beneath; the sandstone will break along faults just like this:

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The faults are enhanced with time by erosion (water, wind etc.), which results in the sandstone fins – intriguing features when viewed from above.  Some of the sandstone fins are more resistant than others, and get preserved (at least for a while) as arches, spires, balanced rocks we see today in the park.

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Delicate Arch ©EarthRelated

This eclectic title expresses my fascination with how Earth history and human culture intertwine.  In 1929, Lora J. Knight commissioned a Swedish architect to build a Scandinavian-style summer home on her property on Emerald Bay, Lake Tahoe area.  Why Scandinavian architecture on the shores of a lake at the border between California and Nevada?  Natural beauty opens up the heart and allows the mind to wonder free and make connections would seldom make otherwise. Mrs. Knight may have been intrigued by the fjord-like shape of the bay, so Scandinavia and Lake Tahoe became a natural link.

Emerald Bay (foreground) entering Lake Tahoe (background) through a gap in a recessional moraine. ©EarthRelated

Emerald Bay and Scandinavia have at least one thing in common: glaciers were present in both places in recent geologic past, and they had a dramatic influence on the modern-day landscape.

Fanette Island – a roche moutonnée (or sheepback): a rock formation created by the passing of a glacier. ©EarthRelated

The Emerald Bay is located in a depression scooped up by glaciers about two million years ago, in Pleistocene, and the Scandinavian fjords are sculpted by glaciers too. Ms. Knight was captivated by the beauty of both places and she started extensive research, which resulted in visits to Scandinavia, and eventually in the building of  Vikingsholm, her summer retreat on the shores of Lake Tahoe.  Besides being carved by glaciers, the Emerald Bay has another interesting feature of glacial origin, the Fannette Island, a roche moutonnée – a piece of remnant basement rock sculpted by the slow movement of a glacier.

Close up of the Fannette Island showing the typical characteristics of a roche moutonnée – a gently inclined upstream slope to the right, and its steep and rough downstream side ( to the left). ©EarthRelated

Lora Knight built a tea-house on top of the island, visible in the picture if you look carefully.  Unfortunately the structure is presently in a state of disrepair, but ah! how I would like to steep and enjoy a perfect cup of tea while pondering the glaciated geologic past and enjoying the view of a magical place like Lake Tahoe.

I fell in love with the Earth when I was sixteen.  I was in the Southern Carpathians of Romania, in a cave, learning about and doing spelunking.  We were crawling through this narrow passage, which at times required exhaling completely in order to be able to fit through and advance.  I stayed behind my travel companions for a short while and for a minute I turned off the little head-lamp attached to my hard hat.  It was the first time experiencing complete darkness – I was frightened, humbled and thrilled beyond expression.  It felt as if the Earth opened up a small space, large enough for me to fit in, and invited me to immerse in her mystery, to experience her secrets, to feel her essence.  For a moment there was no ‘me’ anymore, I was one with ‘her’, and in that moment I knew I wanted to be an earth-scientist.

Rock-embrace. ©EarthRelated

Earth-scientists are experientialists at heart: we have to touch the rocks, to smell them, to (yes!) taste them, to experiment with them, because only then we became intimate with, and understand the stories they tell.  We  are multi-scale thinkers and have to bend our minds to understand, for example, how fluids pass through micrometer scale pores, but also how mountains form, or how continents travel in space and time, in an endless dance  that gives us the amazing landscape we are marveling at today.

Geoscience is about bridging the past, the present and the future, it is about understanding time beyond human scale, it is about seeing the cause in the effect and then being able to visualize the impact of an action at multiple levels and multiple scales, it is about knowing. Knowing of the wind and the wave, the river, the sea and the desert, the deep forces that consume land and ocean floor, only to spew it out later in the form of hot lava that creates the Earth anew, with gentleness or with tremendous, creative force.