Western KS Fossil Lab

08/31/2026

08/10/2026

Making good progress on the “One Big Beautiful Bivalve” (iykyk)

08/10/2026

Secrets of the Sediments: Varves

Take a look at the edge of one of the fossil fish slabs in our gift shop. Running through the rock are dozens of thin, alternating layers that are easy to miss if you’re focused on the fish.

These laminations are VARVES, sediment layers that commonly form on a near-annual cycle. Seasonal shifts in spring runoff, summer algal growth, mineral precipitation and sediment supply can produce distinct layers. In quiet lake bottoms with little biological or physical disturbance, these delicate bands can accumulate with remarkable preservation.

We can observe and test this process in modern lakes. Minnesota’s Elk Lake preserves more than 10,000 years of varved sediment, while Lake Suigetsu in Japan preserves a remarkably detailed sequence extending roughly 70,000 years. These records can be compared with radiocarbon dates, tree-ring sequences, volcanic ash layers and other independent lines of evidence.

Roughly 50 million years ago, the Eocene lakes of the Green River Formation produced similarly fine laminations, preserving both the sediments and the remarkable fish fossils found within them. Some sequences contain millions of laminations. That does not mean geologists simply count every stripe as one year. Individual laminations can form through different processes, so their interpretation and chronology are tested against independent evidence.

Varves are just one archive of deep time among many. Tree rings, ice cores, coral bands, fossil succession, volcanic ash, paleomagnetism and radiometric dating provide additional ways to measure and correlate time. Together, these records let us peel back layer after layer of Earth’s history, revealing a planet with a deep, complex past measured in millions and billions of years.

08/06/2026

This just in! 🐟 Fossil fish are back in the El Quartelejo Museum gift shop!

Last year’s first batch sold out in less than a month, so this time we’re bringing you three different releases throughout the year, each featuring a unique assortment of Fossil Butte fish.

Some specimens are preserved as they were collected, still nestled in their original limestone slabs, while others have been carefully cut and shaped into compact display blocks. Every piece is a genuine 52-million-year-old glimpse into the ancient waters of Fossil Lake.

Stop by the museum today and add a piece to your collection. These make a great gift for fossil lovers, geology enthusiasts, or anyone who wants a little piece of Earth’s history on their shelf!

08/06/2026

Fossil Butte Member: A Collectors Dream

Since its discovery in the 1800s, the Fossil Butte Member of Wyoming’s Green River Formation has captivated scientists, artists, and collectors around the world. Deposited around 52 million years ago in the waters of Fossil Lake, these finely laminated limestones preserve an incredible snapshot of Eocene life.

Millions of fish have come from the formation, along with palm fronds, insects, birds, crocodilians, turtles, bats, and even tiny early horses. The combination of familiar and extinct life makes Fossil Butte a window into a very different world.

Collecting these fossils is a careful process. Thin limestone layers are split with chisels and steel shims, often revealing delicate fish skeletons hidden inside. At night, floodlights are used to cast shadows across the quarry floor, helping collectors spot subtle fossil outlines and carefully work their way down to the specimens.

Our curator recently made his annual pilgrimage to Fossil Butte, and here are a few photos from one of the world’s most famous fossil localities.

08/04/2026

💩 Fossil p**p!

Pictured here are seven newly collected coprolites (fossilized f***s) from the Smoky Hill Chalk. Despite the common misconception, “coprolite” isn’t named for paleontologist Edward Drinker Cope. The name comes from the Greek kopros (“dung”) and lithos (“stone”).

Coprolites are often slightly harder and a different color than the surrounding chalk, making them fairly easy to spot on the surface. Some preserve tiny vertebrae, fish scales, and other bone fragments, offering a direct glimpse into the diets of ancient marine predators. Many also bear curious grooves and trails across their surfaces, thought by some researchers to have been left by benthic scavengers feeding on the waste after it settled to the seafloor.

Everybody eats. Everybody p**ps. Even through geologic time. 💩

08/04/2026

What’s in a Name?

Scientific names are typically built from Latin and Greek roots, often describing an organism’s appearance, behavior, habitat, or honoring a person.

Take our newest specimen, Cladoceramus undulatoplicatus:

• Clado- (Greek) = branch
• -ceramus (Greek) = ceramic or tile, a traditional suffix for this group of giant bivalves
• undulato- (Latin) = wavy
• -plicatus (Latin) = folded or pleated

Together, the name describes a giant inoceramid clam with branching ornamentation and broad, wavy folds, a fitting name for one of the Late Cretaceous’s most distinctive clams.

08/03/2026

The past several days have been packed with outstanding fieldwork and even better company!

One of the groups I had the pleasure of hosting included Dr. Rudy Serbet, paleobotanist and Paleobotany Collections Manager at the University of Kansas, whose research has included numerous expeditions to Antarctica and important work on the its fossil plant record.

Joining him was Dr. Natalia López-Carranza, invertebrate paleontologist and Invertebrate Collections Manager at the University of Kansas, whose published research focuses on the morphology and evolution of brachiopods.

We were also joined by Tim Northcutt, an independent paleontologist known for his work in the Paleozoic rocks of eastern Kansas and the Kansas City region.

Together we visited lower, middle, and upper Smoky Hill Member localities, sharing observations across nearly the entire stratigraphic section. Conversations ranged from paleoecology and taphonomy to stratigraphy and collecting history, making for an incredibly rewarding and collaborative series of field days.

One of the things we’re most proud of at the Western Kansas Fossil Lab is bringing people together. Whether it’s professional researchers, museum staff, students, or dedicated independent paleontologists, these collaborations strengthen our understanding of Kansas’ fossil record and help ensure important discoveries are documented, preserved, and shared.

We’re grateful to everyone who joined us and are already looking forward to the next trip into the chalk!

08/03/2026

New Specimen Spotlight: Cladoceramus undulatoplicatus

We’re excited to highlight a recent standout addition to the fossil lab’s reference collection: a roughly 80 cm (31 inch) specimen of the Late Cretaceous giant bivalve Cladoceramus undulatoplicatus.

This specimen preserves a nearly complete outer margin, distinctive undulating shell ornamentation, and other key details.

Rafting on Cretaceous Ooze

Life on the soft seafloor of the Western Interior Seaway presented a challenge: how do you grow large without sinking?

Cladoceramus met that challenge with an interesting shell design. Built from millions of tiny calcite prisms, its broad, wave-like folds acted like a snowshoe, distributing weight across soft carbonate mud. Despite reaching impressive sizes, the shell remained remarkably thin. Most were crushed during burial, while others quickly weather after exposure, making specimens with complete shells exceptionally rare.

A Global Timekeeper

The first appearance of Cladoceramus undulatoplicatus marks the internationally recognized base of the Santonian Stage, about 86.3 million years ago. Because the species was widespread and existed for a relatively short interval, it serves as an excellent index fossil, allowing geologists to correlate rock layers across North America, Europe, Africa, and Asia.

Centuries Preserved in Stone

A shell more than 2½ feet across required decades of steady growth. It also rested on a chalky seafloor accumulating at fractions of millimeters per year (keep in mind the entire Smoky Hill Member is roughly 600 feet in total thickness today!). Together, the shell and surrounding sediment preserve centuries of history from the floor of the Western Interior Seaway.

This specimen will be a centerpiece of our invertebrate collection while supporting future research, education, and public exhibits. As always, we’re grateful to our local landowners for making discoveries like this possible.

08/02/2026

Fossil Fever!

We’re coming to the end of an incredible stretch of nonstop field days. It’s been hot, dusty, and exhausting, but I wouldn’t trade it for anything.

I also noticed we crossed the 1,000 follower mark. Thanks for following along and sharing in our journey. I have lots of exciting finds to share once things settle down. Stay tuned!