Having collected stromatolites in several locations in New York and Ontario, I was attracted to a small polished piece offered this past October by a dealer at the Rochester Gem and Mineral show. It was labeled Kabamba Jasper – stromatolite, Madagascar. It was a pretty green color, showed physical characteristics of a stromatolitic origin, and best of all, it was reasonably priced. I bought it and came home to research the geology and age of my new find. Immediately, things got complicated.
Bruce Leis has been an enthusiastic collector and researcher of stromatolites for over two decades. He has visited them worldwide, photographing their distinctive patterns and studying their geologic setting. In 2015 he teamed up with retired professor Bruce Stinchcomb and paleo-artist Terry McKee to produce a unique book detailing these wonderful and important geologic features. Anyone interested in earth’s geologic history and the development of life on this planet should enjoy their wonderfully illustrated 176 full page size treatise.
Generally, when Wayne County Gem and Mineral Club packs up the buckets, hammers, passports and bug repellent to head north of the border we are after minerals in the Precambrian rocks of the Grenville Geological Province. But recently we have been able to make an annual stop in younger rocks to collect fossils in Ordovician limestones in the Eganville area of eastern Ontario. Specifically we visit the Haley Quarry in Douglas, Ontario and search the Upper Ordovician Verulam and Lindsey Formations of the Ottawa Group. We did so again this year on Wednesday July 19th.
Published in the June, 2017 WCGMC Newsletter
In late April, six members of Wayne County Gem and Mineral Club joined a Buffalo Geological Society fossil collecting trip to the Cincinnati area led by Jerry Bastedo. We visited several productive sites, but I thought I would direct this month’s site of the month to the southernmost collecting spot we visited. Most of the trip focused on quarries and roadcuts that expose Ordovician and Silurian strata in the Cincinnati Arch. However, on Saturday, we climbed all the way up to the Mississippian by driving several hours south to a modest roadcut in Wax, Kentucky where we collected blastoids in the Glen Dean Formation.
Fossil collectors will travel hours and brave cold temperatures and rain for a chance to collect trilobites. Heck, we will settle for trilobite parts. Most of us will pick up a complete brachiopod and even try to identify it by Genus. Check our garages and you will find hundreds, no thousands, of solitary rugose corals such as Heliophyllum halli and probably almost as many colonial tabulates such as Favosites or Pleurodictyum corals. We’ll jump for a gastropod and drool when a orthonic (straight-backed) cephalopod pops out in outcrop or shows himself (herself?) in a stone on the beach. And need I say more than Eurypterid to get you excited? BUT, who among us loves Bryozoans enough to even take a branching colony or a fan-like species home. And if you do take one home does it end up identified and in your collection? My guess is it does not. Perhaps I can change that.
You may have heard the theories that modern birds are descendent from dinosaurs that roamed the planet in the Mesozoic Era (225-65 million years ago), like the Velociraptor depicted above. And that some of those dinosaurs, both large and small, are now purported to have had feathers. But, have you seen any of the direct evidence?
Article was published in the February 2017 WCGMC Newsletter
Sometimes it is fun to just explore for fossils or minerals by visiting an unknown location, perhaps one with potentially appropriate geology, but not a site with documented fossils or minerals. One may not find much, but occasionally one stumbles onto something completely unexpected and equally interesting. In the fall of 2015 Stephen Mayer and I had such an experience when we decided to investigate the geology along Reeder Creek in Varick, NY.
Leave it to the field trip leader of the Wayne County Gem and Mineral Club, Bill Chapman, to find something new! Well, not exactly new, but certainly unusual. Plumalina plumaria were first described by Hall (1878). Yes, they look like feathers, and one might want to classify them as ferns or plants of some sort, but the latest understanding of these rather rare fossils is that they were hydroids (Muscente and Allmon, 2013). Hydroids are a class of small predators that are related to jellyfish. Dominated by soft-body parts hydroids are not well preserved in the fossil record causing extinct species to often be labeled Incertae Sedis in many fossil lists. Incertae Sedis are extinct organisms with unknown or uncertain relation to known phyla.
In mid-September, Bill Lesniak and I ventured a couple states west and south on a Buffalo Geological Society four-day fossil trip led by Jerry Bastedo. Our first quarry stop on a pleasant sunny Friday morning was in southeast Indiana at the Napoleon Quarry in Ripley County. It was a great site, but for me it might have been all that much better had I done a little research before the trip. But better late than never and here is what I have since learned.
I have trouble finding one lone whole trilobite when I go out collecting in the Devonian of New York. And then along comes this note from central Poland where researcher Blazej Blazejowski reports that the eyeless trilobite Trimerocephalus chopini can be found preserved in trains with head to tail (or in trilobite lingo with cephalon to pygidium). He infers that the queues actually represent migratory chains as the ancient arthropods marched across the seafloor, perhaps in an unsuccessful effort to escape near and present danger.
Wouldn’t it be neat to find a queue of arthropods after splitting some Hamilton Group shales? Or maybe there was no reason for New York trilobites to migrate? Perhaps life was just too good to move?
Blazejowski, B., et. al., 2016 Ancient animal migration: a case study of eyeless dimorphic Devonian trilobites from Poland, Palaeontology, V. 59, p. 743-751.
Many thanks to Stephen Mayer for writing this collecting trip note for the August WCGMC newsletter and also for allowing me to post it my blog.
By Stephen Mayer
Tammy and I are back from a vacation in the desert southwest. Naturally, we took some time between visits to National Parks to do a little fossil and mineral collecting in Utah. The setting and geology are quite different than in western New York.
Very thick shale and calcareous mudstones are widespread in Millard County, west-central Utah and contain some of the best Cambrian biotas in the world. Not only are there 505-520 million year old fossils abundant, but also recent volcanism in the same region has left its mark with abundant rocks and minerals. Specifically, well preserved trilobites and beautiful topaz crystals can be collected.
It was not that long ago that Wayne County and the rest of western New York were located just south of the equator while basking in tropical temperatures. A large and shallow inland sea dominated the region with high mountains to the east and a shallow continental margin to the west. The sea was replete with life. Invertebrates dominated the sea bottom, corals and brachiopods filtered nutrients from the seawater to survive, while trilobites, cephalopods (squid), and a host of other scavenger and predator species roamed the benthic (sea bottom) region feeding on them. Numerous species of gastropods (snails) and bivalves (clams) were abundant also. The seas above were dominated by large armored fish (i.e. Dunkleosteus) and a multitude of smaller fish. It was the Devonian Period of earth’s history. It was the age of fish.
It happened in a flash. At our April Friday club meeting, trip leader Bill Chapman announced that we had been granted permission to enter Seneca Stone Quarry on the upcoming Monday and wondered who might be free and interested. Seneca Falls is quite close and apparently we either have a lot of idle folk in the club or a lot of anxious collectors ready to get busy. Eleven folks indicated interest and in a slight mist all eleven converged on the quarry site just south of Seneca Falls ready to collect on Monday morning April 11th.
co-authored with Stephen Mayer for the March 2016 Wayne County Gem and Mineral Club newsletter
As geologists and amateur fossil and rock hounds, many of us focus on the Proterozoic minerals of the Adirondacks and/or the Paleozoic fossils of western and central New York State. However, two very important and much overlooked prehistoric animals roamed New York State approximately 10,000 years ago. The Woolly Mammoth and the American Mastodon were prominent residents in our own backyards.
OK. Admit it, you thought this would be a note about the spectacular doubly terminated clear quartz crystals hiding in vugs in dolostones. Referred to as Herkimer diamonds, and known to mineral enthusiasts from across the country simply as “Herks” there has sure been enough written about them to last a lifetime. And goodness knows we all like to travel to Herkimer County to collect them. But no, this is not just another article about quartz.
Stromatolites are bio-chemically supported structures formed in shallow water when microscopic cyanobacterial material (formally known as blue-green algae) acts to bind and eventually cement sedimentary grains into what are essentially microbial mats. Changing climatic conditions, water depth, sediment influx, or the biology of the micro-organisms themselves leads to finely layered biochemical accretionary structures.
There are many well known fossil collecting sites in the creeks and gullies draining into the Finger Lakes (places like Kashong Gully, Deep Run, and Portland Point to name a few). But for every well documented site there are a dozen lesser known locales where drainages into the Finger Lakes expose the fossil rich strata of the 385 million year old Middle Devonian Hamilton Group. Indian Creek, near Williard on the eastern side of Seneca Lake, is one such location.
The New York State Geological Association (NYSGA) held its annual meeting in Plattsburgh in September. The event, hosted by SUNY-Plattsburgh, featured field trips to several Adirondack sites and I attended one on both days of the event. But we will leave that to a subsequent post. This note focuses on an outcrop just outside Plattsburgh where the gastropod Maclurites magnus can be found. Encouraged to visit the site by a SUNY-Plattsburgh geology student, I found time Tuesday September 15th to spend a couple hours walking the outcrop with New York Paleontology Society Field Trip Leader Ray McKinney, who just so happens to live in Plattsburgh. Meeting him on this trip was an unexpected bonus to attending NYSGA.
Having been rained and flooded out in June, the WCGMC found a way to squeeze a trip Alden into its August schedule visiting the ever popular site on Saturday August 29th. This time the weather was perfect, the water was low, and, as always the fossils were there to be collected. The formidable Ledyard shale cliffs in the creek bed have been a favorite site for collectors for several decades, but winter erosion always seems to expose new ones to extract with a little digging.
Sometimes things get named too fast and once labeled incorrect associations are very difficult to rectify. Have you ever seen “turritella agate” at your favorite fossil dealer’s table? It has often been polished into cabochons designed to display the whorls of the spiral shaped shell and the agate that has filled the apertures. Raw specimens are attractive as well.
It was a large, enthusiastic group of all ages from two local clubs that gathered on August 9th to trek into Green’s Landing on a fossil hunt. Stephen Mayer led the Wayne County Gem and Mineral Club contingent while Dan Krisher (also a WCGMC member) led the Rochester Academy of Science Fossil Group. The total group numbered 27 with about an equal number from each organization. It was a wonderful way for folks in each group to meet fellow fossil enthusiasts while doing what they enjoy most, digging in the Middle Devonian. And Green’s Landing was ready for us with as diverse and prolific assemblage of fossils as one could imagine.