Photo/Illutration Samples of the varves at the Fukui Prefectural Varve Museum. (Tsunetaka Sato)

A cold snap had arrived, and the water surface was choppy due to strong winds blowing from the Sea of Japan.

Lake Suigetsuko is situated in the Wakasa district of southwestern Fukui Prefecture. The lake bottom is stacked with thin layers of clay called varves that provide a geological record of the past 70,000 years, much like growth rings of a tree.

Mud continued to accumulate there quietly and solidified, as no creature inhabits the lacustrine bottom and no river flows directly into Suigetsuko, a “miracle lake” with few parallels elsewhere.

The varves are useful, for example, for climate change research as a “yardstick of time” that preserves clues to the properties of every single year.

Plant pollen trapped in the lacustrine bottom layers gives researchers an opportunity to learn about vegetation of a certain time period and reconstruct how Japan’s landscape looked during glacial and hot epochs. The varves also contain vestiges of earthquakes and flood events.

Yet another year has been quietly engraved on the lake bottom, just like memories that stack up in our brains.

This last day of 2022 is probably, for many, a day for looking back on events of the past year.

Samples of the geological formations are on exhibit at the Fukui Prefectural Varve Museum not far from Lake Suigetsuko. They are, in places, streaked with whitish layers of volcanic ash from eruptions in the Kyushu and Sanin regions deposited across broad areas of the Japanese achipelago.


Similar layers have been observed in other areas as well. Such features are known as “key beds” in the jargon of geology.

Key beds are easily distinguishable from the other layers when stripes of geological formations from different localities are studied. And they are distributed over broad regions, where they were deposited around the same time.

The key beds serve as benchmarks for comparing geological formations from mutually separated areas and determining the ages of the layers.  They also help to date archaeological ruins.

If varves may be likened to memories that stack up from year to year in the minds of individuals and groups of people, key beds could be compared to major events that leave behind evenly synchronized memories in the minds of people from all walks of life.

Russia’s invasion of Ukraine this year was engraved broadly in the minds of people across the globe. 

The national flag of Ukraine, with its blue and yellow motif, is omnipresent in cyberspace as well as street landscapes.

Public interest rose, in Japan as elsewhere, in helping evacuees from Ukraine. Our livelihoods were also affected by a shift in the global energy situation caused by the war there.

By coincidence, this year also saw the death, in August, of Russia’s Mikhail Gorbachev, the last leader of the Soviet Union. The news probably reminded many people of the surprise they felt when the Cold War was declared over in 1989 and the Soviet Union ceased to exist in 1991.

In Japan, former Prime Minister Shinzo Abe was fatally shot in July.

The shocking event, in the middle of an election campaign, brought a spotlight on the Unification Church, its shady practices and deep ties to the political establishment.

Public opinion was split over the government’s decision to host and go ahead with a state funeral for Abe in September.

The year also saw a succession of heartrending accidents that claimed numerous lives in an instant.

A sightseeing boat sank off Shiretoko Peninsula, Hokkaido, in April. A crowd crush during Halloween festivites in Seoul in October is still fresh in our minds.

Some events carried over from previous years.

Memories of the novel coronavirus pandemic are still stacking up. Many people recall how they were infected themselves, how others who are close to them were infected, and what side effects they had from COVID-19 vaccine shots.


Let’s ask: Do you remember where you were and what you were doing when you first learned about such and such an event?

Many people remember such personal details if the event had a huge impact on their lives.

Memories of the Great East Japan Earthquake and tsunami of March 11, 2011, which triggered the Fukushima nuclear disaster, undoubtedly remain etched in people’s minds.

In the aftermath of the triple disaster, people across Japan and elsewhere used to share accounts of that moment with whoever we happened to see, sometimes for the first time in a long while. There would be occasions when we also shared sorrow and joy with them.

Memories of shocking events, like the deaths of individuals who had a huge impact on society, as well as accidents, crimes and disasters, are shared. These amount to “key beds” of sorts.

But different people may assign those events different places and meanings in their own memories, or the time frame of their respective “varves.”

Some take things in the same way that you do. Perhaps they are among your relatives, friends, workplace colleagues or schoolmates. Perhaps they come from broader reaches of your personal connections.

Collective memories of a group are formed where individual memories meet. And they may undergo an infinite variety of developments.

Remembrances of bygone years are sometimes passed on to posterity, but are sometimes consigned to oblivion in favor of emotional and social stability. Even so, they may still be rediscovered and given new life on the spur of the moment.

If we stick to the “key beds” analogy, when some phenomenal incident equivalent to crustal deformation occurs, there may be instances when the surface of memories of individuals as well as their key beds may also be pushed to the surface.

Talking of places and meanings that memories of events are assigned within the whole of individual and collective memories, it is probably essential to realize the scope and limits of the extent to which they can be shared.

We should give our thoughts to, and get to know, others who may not assign the same meanings that we do. Doing so will help expand the scope of our “empathy,” much talked about these days in Japan’s literary circles, which is about putting yourself in somebody else’s shoes.

We should bear in mind that there are key beds where those who live in the same age, on the same Japanese islands and on the same Earth go on engraving their vestiges together, and those key beds may manifest themselves in a whole variety of shapes.


Goings-on of the contemporary age not only go down in people’s memories but are also preserved in huge volumes of records, such as books, newspapers, magazines, online resources and other forms of media. And even that is not the whole story.

Returning to the initial topic of geological formations in the real world, radioactive fallout from nuclear tests, plastic waste and ash derived from burning coal stand as vestiges to what we are doing to our planet. The negative side of our human presence thus continues to be engraved there.

How will people of the future evaluate the coming year 2023 if they are ever to dig up and study geological formations from our time?

The best thing we could hope to do is to engrave varves that we can be proud of in what little way we can.

--The Asahi Shimbun, Dec. 31