Ode on a Fish Fossil

Feature photo: Fish Fossil, Green River Formation, Western United States.

Article and photos by FMN Stephen Tzikas

Heard melodies are sweet, but those unheard
Are sweeter; therefore, ye soft pipes, play on;
Not to the sensual ear, but, more endear’d,
Pipe to the spirit ditties of no tone

So goes the second stanza of John Keats’ “Ode on a Grecian Urn” that I vividly remember from my High School days. These were the same words that flashed in my mind upon viewing a fish fossil my friend gave me a few months ago. Funny thing it is, how the poet sometimes seems to precede the scientist in me.

The famous English poet’s ode appreciates the timeless art on an urn, and so too, the fish fossil in my mind was a presentation of beauty and immortality, having patiently waited millennia to tell its story. And just as in the original poem, we have the conclusion of the poem which can equality apply to the fish fossil:

When old age shall this generation waste,
Thou shalt remain, in midst of other woe
Than ours, a friend to man, to whom thou say’st,
“Beauty is truth, truth beauty,”—that is all
Ye know on earth, and all ye need to know.

While these herring fish fossils have their origin in the limestone of the Green River Formation, residents of Fairfax County do not need to go that far, or even leave the county, to find fossils.

My exposure to fossils began as a child reading the How and Why Wonder Book of Dinosaurs, which indicated that the first, near complete, skeleton of a dinosaur was discovered in Haddonfield, NJ. Since that was in my home state, I hoped to visit the town one day. Eventually I would indeed visit that town to see the Hadrosaurus statue commemorating the find in 1858 that started the field of dinosaur paleontology.

During the Triassic Period (201 – 252 Mya), dinosaurs left behind both bones and footprints in Virginia. Fish from local lakes were preserved during the Jurassic (145 – 201 Mya). In the 1920s, dinosaur tracks were discovered at nearby Oak Hill. The Northern Virginia Community College (NVCC) offers many one-day one-credit geology excursions in our general area. I completed many of these courses and had the opportunity to see fossils during these excursions.

On June 24, 2017, I attended the geological field study trip for the

Oak Hill Dinosaur Skin Print, June 24, 2017, 1.5 by 2 Foot Scale

Triassic-Jurassic Rifting of North America in the Triassic Lowlands of Northern Virginia. One of the sites on that trip was the Oak Hill Estate (Home of President James Monroe). This site contains dinosaur tracks. The rock type here is the Lower Jurassic Turkey Run Formation (197 Mya). The fossils are of Eubrontes foot tracks and a rare skin print (see my photograph). Also fossilized was a lungfish burrow from the Jurassic, which had estivated to survive through the summer. Ripples, raindrops imprints, and bioturbation were evident in fossils we saw.

Photo:Holmes Run Gorge Fossils, Nov 18, 2017. Shown here are fossils (Skolithos Linearis) in well-cemented quartzite of the early Antietam Formation. These are Virginia’s oldest fossils and date to the Cambrian Period (485 – 539 Mya).

On November 18, 2017, I took another NVCC geology excursion for the Geologic History of Holmes Run Gorge at the Dora Kelley Nature Park in Alexandria. At the main gorge area we discussed the quartz rocks. Quartz is the last mineral in the Bowen reaction series of fractional crystallization.

I find the Bowen reaction series fascinating as it has some correlation to fractional distillation in my field of chemical engineering. I collected a sample of cloudy white milky quartz, which is extremely resistant to weathering. The cloudiness of milky quartz comes from microscopic inclusions of fluids that have been encased in the crystal from the time the crystal first grew. Our professor showed multiple examples of Quartzite with slashes (see my photograph). High-energy waters transported these cobblestone size rocks originating from the Harper’s Ferry Antietam Formation. The formation was largely quartz sandstone with some quartzite and quartz schist. This formation underwent metamorphic changes. This Quartzite is a hard, non-foliated metamorphic rock that was originally pure quartz sandstone. The sandstone was converted into quartzite through heating and pressure usually related to tectonic compression within orogenic belts. Most noteworthy were the tubeworm line burrows, about a half billion years old. Samples were numerous.

Drawing and Learning about Fossils at Hidden Oaks Nature Center, May 6th, 13th and 20th

Photo: Courtesy of the Virginia Department of Conservation and Recreation

May 6, 13 and 20, 2023

Cost: $60.00 Sign-up through Fairfax County Park Authority
Class Code: L8Q.EJQH

7701 Royce Street
Annandale, VA, 22003

Sign-up through Fairfax County Park Authority Class Code: L8Q.EJQH

Fossils are fascinating!! Delve into the ancient world of plant, marine and dinosaur fossils by drawing fossils from the Hidden Oaks collection.  Learn how fossils form, go on a prehistoric-themed hike and try matching fossils to their ancient animal or plant. Your choice of ink pen, colored pencil, or watercolor can be used.


FMN Annual Meeting, Elections and Graduation of Fall 2022 Class, December 12th

Monday, December 12, 2022
7 pm
Zoom (email [email protected] for link if you are not an FMN member)

We will be holding our Annual Meeting on Zoom, Monday, December 19th at 7 pm. We will be celebrating the graduation of the Fall 2022 Basic Training Class and have a short business meeting.

In addition, our own FMN Jerry Peters will speak on “Skolithos, Early Cambrian Fossils in Northern Virginia”. Skolithos linearis is a trace fossil (ichnofossil) that is the most common fossil found in Fairfax County. The animal that formed the fossils thrived in ocean beaches on the east side of the continent around 540 million years ago, about the time of the Cambrian revolution when all major animal phyla started appearing in the fossil record. Jerry will discuss the source of these fossils (Antietam formation outcropping on the western slopes of the Blue Ridge) and the several sinks (places they can be found today) in Fairfax County. He will also review key events in the 540 million years of geologic history that these fossils trace.

Jerry Peters is retired from a career as a consulting environmental scientist – conducting Environmental Impact Statements, municipal wastewater facilities planning, hazardous waste management, pollution prevention, hazardous waste site remediation and program guidance, etc. He has a Master’s degree from Virginia Tech in Environmental Science and Engineering (Water Resources) and a Bachelor of Arts degree, biology major, from University of Virginia. Jerry serves as an elected Director of the Northern Virginia Soil & Water Conservation District (NVSWCD), working with the organization for the past 13 years in a variety of positions. He also serves as the District representative to the Fairfax County Tree Commission and helped draft the 2019 Tree Action Plan. Jerry is also Founder of Green Fire, a non-profit to improve wildlife habitats in Fairfax County – and has been active in the Environment and Parks Committee of the Great Falls Citizen’s Association, leading a project to naturalize an oak grove in Great Falls Grange. Finally, many of us know Jerry from his work over many years for the Fairfax Master Naturalists. He helped start up Fairfax Master Naturalists in 2007 as a volunteer on the Coordinating Committee and served as Advanced Training chair. He was awarded Honorary FMN membership in 2007. In 2008 he completed the FMN Basic Training and became a regular member. He has been a member of the FMN Training Committee since 2007, instructing new Master Naturalists in Biogeography, Land Use, and Urban Systems.