Northern Michigan Festival Pays Homage to the Humble Puddingstone

Summer is the time for outdoor festivals, and there’s one for every interest—even obscure rock enthusiasts. (The mineral formations, not the music.)

The third annual "Puddingstones of Cheboygan County" festival is taking place this weekend—August 5 and 6—in downtown Cheboygan, Michigan. The gathering honors a rock you’ve probably never heard of, one that’s only found in a select set of places, one of which is northern Michigan.

Puddingstones are a type of Jasper conglomerate, consisting of many individual rocks within a larger one. They were formed amid the glacial drift in the Great Lakes region and contain Jasper quartz, Precambrian Canadian Shield rocks, sandstone, and other redeposited sand and pebbles.

The rocks earned their name from early British settlers who thought the rocks looked like boiled suet pudding with berries. There are actually several types of so-called "puddingstones," including Hertfordshire, Schunemunk, and Roxbury, the last of which is the state rock of Massachusetts.

At this weekend’s festival, stone and mineral exhibitors are displaying their goods, rock-related events are taking place, there's an Easter-egg style puddingstone hunt, live music, a suet pudding baking contest, and a puddingstone contest with categories like "most red in a stone" and "images seen in a stone."

Michiganders apparently really love their rocks: The state also holds a Petoskey Stone Festival every year to honor their own state stone.

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Human Activity Has Permanently Altered Earth, for Better or Worse (Mostly Worse)

Modern humans have roamed Earth for just a few hundred thousand years. In the grand scheme of things, that's a very short period. But in that time, we’ve triggered mass extinctions of plants and animals, polluted the planet, and developed nuclear weapons—and our legacy will linger in both nature and the geologic record long after historical records have been lost, according to Ted-ED’s video below.

Modern humans have altered the Earth’s landscape and atmosphere so profoundly that some scientists say we’ve ushered in a new epoch called the Anthropocene, or "new age of humankind," from anthropo (human) and cene (new). Before this, we were living in the Holocene (meaning “entirely recent”), which began around 11,700 years ago and faded sometime around 1950.

The 1950s ushered in both the plastics revolution and the atomic age, both of which permanently introduced chemicals into Earth’s fossil record. Meanwhile, humans have also shaped long-term plant and animal evolution with agriculture, fishing, and hunting. In short, our actions have long-term consequences, even if the human species ends up being a blip on the geologic time scale. Remember that the next time you drink from a plastic bottle, or see a cloud of smoke billowing through the sky.

This Just In
Spelunkers Discover New Caverns in Montréal's Ancient Cave Network

An ancient cave system beneath a Montréal park is much more vast than experts believed, the National Post reports.

In 1812, a farmer discovered a cave underneath his property in Montréal’s present-day Saint-Léonard borough. Once used to stockpile ammunition and conceal soldiers during the Rebellions of 1837, the Saint-Léonard cave system in Parc Pie XII is today a tourist attraction and historical landmark. But some speleologists (cave experts) suspected there was more to the natural wonder than met the eye.

Beginning in 2014, two amateur explorers named Daniel Caron and Luc Le Blanc began searching for undiscovered passages in the Saint-Léonard caverns, according to National Geographic. By 2015 they had some leads; in October 2017, they used drills and hammers to break down a cave’s wall to reveal a new cavern.

The stalactite-filled chamber has soaring 20-foot ceilings, and it's connected to a serpentine network of underground tunnels. These passages formed during the Ice Age around 15,000 years ago, when glacier pressure splintered underground rock.

So far, Caron and Le Blanc have explored between 820 to 1640 feet of virgin cave passage, and expect to find even more. They believe the vast network sits atop an aquifer, and ultimately leads to the Montréal water table.

Spelunking the Saint-Léonard cave system is challenging—some passages are filled with water or require special climbing or rock-breaking equipment. The explorers hope that the caves will be easier to investigate during the dry season, and that the receding waters will allow them to reach new depths below Montréal’s surface.

[h/t National Post]


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