Showing posts with label huntress. Show all posts
Showing posts with label huntress. Show all posts

Tuesday, 15 November 2022

GULLS ON THE FORESHORE: T'SIK'WI

A gull cries in protest at not getting his share of a meal

Gulls, or colloquially seagulls, are seabirds of the family Laridae in the suborder Lari. 

The Laridae are known from not-yet-published fossil evidence from the Early Oligocene — 30–33 million years ago. 

Three gull-like species were described by Alphonse Milne-Edwards from the early Miocene of Saint-Gérand-le-Puy, France. 

Another fossil gull from the Middle to Late Miocene of Cherry County, Nebraska, USA, has been placed in the prehistoric genus Gaviota

These fossil gulls, along with undescribed Early Oligocene fossils are all tentatively assigned to the modern genus Larus. Among those of them that have been confirmed as gulls, Milne-Edwards' "Larus" elegans and "L." totanoides from the Late Oligocene/Early Miocene of southeast France have since been separated in Laricola.

Gulls are most closely related to the terns in the family Sternidae and only distantly related to auks, skimmers and distantly to waders. 

A historical name for gulls is mews, which is cognate with the German möwe, Danish måge, Swedish mås, Dutch meeuw, Norwegian måke/måse and French mouette. We still see mews blended into the lexicon of some regional dialects.

In the Kwak̓wala language of the Kwakiutl or Kwakwaka'wakw, speakers of Kwak'wala, of the Pacific Northwest and my family, gulls are known as t̕sik̕wi. Most folk refer to gulls from any number of species as seagulls. This name is a local custom and does not exist in the scientific literature for their official naming. Even so, it is highly probable that it was the name you learned for them growing up.

If you have been to a coastal area nearly everywhere on the planet, you have likely encountered gulls. They are the elegantly plumed but rather noisy bunch on any beach. You will recognize them both by their size and colouring. 

Gulls are typically medium to large birds, usually grey or white, often with black markings on the head or wings. They typically have harsh shrill cries and long, yellow, curved bills. Their webbed feet are perfect for navigating the uneven landscape of the foreshore when they take most of their meals. 

Most gulls are ground-nesting carnivores that take live food or scavenge opportunistically, particularly the Larus species. Live food often includes crab, clams (which they pick up, fly high and drop to crack open), fish and small birds. Gulls have unhinging jaws which allow them to consume large prey which they do with gusto. 

Their preference is to generally live along the bountiful coastal regions where they can find food with relative ease. Some prefer to live more inland and all rarely venture far out to sea, except for the kittiwakes. 

The larger species take up to four years to attain full adult plumage, but two years is typical for small gulls. Large white-headed gulls are typically long-lived birds, with a maximum age of 49 years recorded for the herring gull.

Gulls nest in large, densely packed, noisy colonies. They lay two or three speckled eggs in nests composed of vegetation. The young are precocial, born with dark mottled down and mobile upon hatching. Gulls are resourceful, inquisitive, and intelligent, the larger species in particular, demonstrating complex methods of communication and a highly developed social structure. Many gull colonies display mobbing behaviour, attacking and harassing predators and other intruders. 

Certain species have exhibited tool-use behaviour, such as the herring gull, using pieces of bread as bait with which to catch goldfish. Many species of gulls have learned to coexist successfully with humans and have thrived in human habitats. Others rely on kleptoparasitism to get their food. Gulls have been observed preying on live whales, landing on the whale as it surfaces to peck out pieces of flesh. They are keen, clever and always hungry.

Friday, 11 November 2022

TARANTULAS AND AMMONOIDS OF NEVADA

Hiking the hills of Nevada looking for David Taylor's faunal succession based on ammonoids established for the Late Hettangian to Early Sinemurian interval in the Western Cordillera.

The land here is free of trees with low only low groupings of gnarly scrub to work through to get to the bedrock below. 

Our work here was in October, which is a time when Nevada is cool in the mornings and evenings, but still surprisingly hot during the day. It is also tarantula breeding season and my first glimpse of these spiders in volume at field sites. 

It was a tremendous experience to walk through time and compare the fossil assemblages here with our own in the Canadian Rockies. Here the faunal sequence consists of one zone and four informal biochronologic units or assemblages and was outlined by Taylor as follows: Paracaloceras morganense assemblage, Badouxia oregonensis assemblage, Canadensis Zone, Metophioceras trigonatum assemblage and Coroniceras involutum. They matched up to specimens we collected over three field seasons to similar faunal outcrops of Late Hettangian to Early Sinemurian of the Last Creek and Tyaughton area of the Canadian Rockies.

The succession also correlates with the interval delineated by the Northwest European Angulata Zone through the Lyra Subzone. Two new genera (Guexiceras and Tipperoceras) are described along with 23 new species. 

The phylogenetic relationships of the earliest Jurassic ammonite superfamilies indicate that it is useful to include under the Psiloceratida, the Psilocerataceae and their derivatives including the Lytocerataceae

The Arietitaceae were derived from Hettangian Lytocerataceans. There is still much work to be done to work out the finer points of comparison between British Columbia's Triassic fauna and those that lived and died in what is now Nevada, USA, but enjoyable work it it.

Thursday, 10 November 2022

AMMONOIDS, LIMESTONE AND SALT: HALLSTATT

Hallstatt Salt Mines, Austria / Permian Salt Diapir
The Hallstatt Limestone is the world's richest Triassic ammonite unit, yielding specimens of more than 500 ammonite species.

Along with diversified cephalopod fauna  — orthoceratids, nautiloids, ammonoids — we also see gastropods, bivalves, especially the late Triassic pteriid bivalve Halobia (the halobiids), brachiopods, crinoids and a few corals. We also see a lovely selection of microfauna represented. 

For microfauna, we see conodonts, foraminifera, sponge spicules, radiolaria, floating crinoids and holothurian sclerites —  polyp-like, soft-bodied invertebrate echinozoans often referred to as sea cucumbers because of their similarities in size, elongate shape, and tough skin over a soft interior. 

Franz von Hauer’s exhaustive 1846 tome describing Hallstatt ammonites inspired renowned Austrian geologist Eduard Suess’s detailed study of the area’s Mesozoic history. That work was instrumental in Suess being the first person to recognize the former existence of the Tethys Sea, which he named in 1893 after the sister of Oceanus, the Greek god of the ocean. As part of the Northern Limestone Alps, the Dachstein rock mass, or Hoher Dachstein, is one of the large karstic mountains of Austria and the second-highest mountain in the Northern Limestone Alps. It borders Upper Austria and Styria in central Austria and is the highest point in each of those states.

Parts of the massif also lie in the state of Salzburg, leading to the mountain being referred to as the Drei-Länder-Berg or three-state mountain. Seen from the north, the Dachstein massif is dominated by the glaciers with the rocky summits rising beyond them. By contrast, to the south, the mountain drops almost vertically to the valley floor. The karst limestones and dolomites were deposited in our Mesozoic seas. The geology of the Dachstein massif is dominated by the Dachstein-Kalk Formation — the Dachstein limestone — which dates back to the Triassic.

Hallstatt and the Hallstatt Sea, Austria
There were several phases of mountain building in this part of the world pushing the limestone deposits 3,000 metres above current sea level. The rock strata were originally deposited horizontally, then shifted, broken up and reshaped by the erosive forces of ice ages and erosion.

The Hallstatt mine exploits a Permian salt diapir that makes up some of this area’s oldest rock. 

The salt accumulated by evaporation in the newly opened, and hence shallow, Hallstatt-Meliata Ocean. This was one of several small ocean basins that formed in what is now Europe during the late Paleozoic and early Mesozoic when the world’s landmasses were welded together to form the supercontinent Pangea. 

Pangea was shaped like a crescent moon that cradled the famous Tethys Sea. Subduction of Tethyian oceanic crust caused several slivers of continental crust to separate from Pangea, forming new “back-arc basins” (small oceans formed by rifting that is associated with nearby subduction) between the supercontinent and the newly rifted ribbon continents.

The Hallstatt-Meliata Ocean was one such back-arc basin. As it continued to expand and deepen during the Triassic, evaporation ceased and reefs flourished; thick limestone deposits accumulated atop the salt. When the Hallstatt-Meliata Ocean closed in the Late Jurassic, the compression squeezed the low-density salt into a diapir that rose buoyantly, injecting itself into the Triassic limestones above.

The Hallstatt salt diapir and its overlying limestone cap came to rest in their present position in the northern Austrian Alps when they were shoved northward as nappes (thrust sheets) during two separate collision events, one in the Cretaceous and one in the Eocene, that created the modern Alps. It is from the Hallstatt salt diapir that Hallstatt, like so many cities and towns, gets its name.

Deposits of rock salt or halite, the mineral name of sodium chloride with the chemical formula of NaCl, are found and mined around the globe. These deposits mark the dried remains of ancient oceans and seas. Names of rivers, towns and cities in Europe — Salzburg, Halle, Hallstatt, Hallein, La Salle, Moselle — all pay homage to their connection to halite and salt production. The Greek word for salt is hals and the Latin is sal. The Turkish name for salt is Tuz, which we see in the naming of Tuzla, a salt-producing region of northeastern Bosnia-Herzegovina and in the names of towns that dot the coast of Turkey where it meets the Black Sea. Hallstatt with its salt diapir is no exception.

The salt-named town of Hallstatt sits on the shores of the idyllic Hallstätter Sea at the base of the Dachstein massif. Visiting it today, you experience a quaint traditional fishing village built in the typical upper Austrian style. Tourism drives the economy as much as salt as this area of the world is picture-perfect from every angle.

Space is at a minimum in the town. For centuries, every ten years the local cemetery exhumes the bones of those buried there and moves them to an ossuary to make room for new burials. The Hallstatt Ossuary is called Karner, Charnel House, or simply Beinhaus (Bone House). Karners are places of secondary burials. They were once common in the Eastern Alps, but that custom has largely disappeared.

Hallstatt Beinhaus Ossuary, Hallstatt, Austria
A collection of over 700 elaborately decorated skulls rest inside the ossuary. They are lined up on rows of wooden shelves that grace the walls of the chapel. Another 500 undecorated skulls, bare and without any kind of adornment, are stacked in the corners.

Each is inscribed and attached to a record with the deceased's name, profession and date of death. The Bone House is located in a chapel in the basement of the Church of Saint Michael. The church dates from the 12th century CE. 

Decorating the skulls was traditionally the job of the local gravedigger and an honour granted to very few. At the family's request, garlands of flowers were painted on the skulls of deceased as decorative crowns if they were female. The skulls of men and boys were painted wreaths of oak or ivy.

Every building in Hallstatt looks out over the Hallstätter Sea. This beautiful mountain lake considered one of the finest of Austria's Salzkammergut region. It lies at the northern foot of the Dachstein mountain range, sitting eight-and-a-half kilometres long and two kilometres wide. The shoreline is dotted by the villages of  Obertraun, Steeg, and Hallstatt.

The region is habitat to a variety of diverse flora and fauna, including many rare species such as native orchids, in the wetlands and moors in the south and north.

Linked by road to the cities of Salzburg and Graz, Hallstatt and its lake were declared one of the World Heritage sites in Austria in 1997 and included in the Hallstatt-Dachstein Salzkammergut Alpine UNESCO World Heritage Site. The little market village of Hallstatt takes its name from the local salt mine.

Hallstatt, Salzkammergut region, Austria
The town is a popular tourist destination with its quaint shops and terraced cafes. In the centre of town, the 19th-century Evangelical Church of Hallstatt with its tall, slender spire is a lakeside landmark. You can see it here in the photo on the left.

Above the town are the Hallstatt Salt mines located within the 1,030-meter-tall Salzburg Salt Mountain. They are accessible by cable car or a three-minute journey aboard the funicular railway. There is also a wonderful Subterranean Salt Lake.

In 1734, there was a corpse found here preserved in salt. The fellow became known as the Man in Salt. Though no archaeological analysis was performed at the time — the mummy was respectfully reburied in the Hallstatt cemetery — based on descriptions in the mine records, archaeologists suspect the miner lived during the Iron Age. This Old Father, Senos ph₂tḗr, 'ɸatīr 'father' may have been a local farmer, metal-worker, or both and chatted with his friends and family in Celtic or Proto-Celtic.

Salt mining in the area dates back to the Neolithic period, from the 8th to 5th Centuries BC. This is around the time that Roman legions were withdrawing from Britain and the Goths sacked Rome. In Austria, agricultural settlements were dotting the landscape and the alpine regions were being explored and settled for their easy access to valuable salt, chert and other raw materials.

The salt-rich mountains of Salzkammergut and the upland valley above Hallstatt were attractive for this reason. The area was once home to the Hallstatt culture, an archaeological group linked to Proto-Celtic and early Celtic people of the Early Iron Age in Europe, c.800–450 BC.
Bronze Age vessel with cow and calf

In the 19th century, a burial site was discovered with 2,000 individuals, many of them buried with Bronze Age artefacts of amber and ivory.

It was this find that helped lend the name Hallstatt to this epoch of human history. The Late Iron Age, between around 800 and 400 BC, became known as the Hallstatt Period.

For its rich history, natural beauty and breathtaking mountainous geology, Hallstatt is a truly irresistible corner of the world.

Salzbergstraße 1, 4830 Hallstatt.  https://www.salzwelten.at/en/home/

Photo: Bronze vessel with cow and calf, Hallstatt by Alice Schumacher - Naturhistorisches Museum Wien - A. Kern – K. Kowarik – A. W. Rausch – H. Reschreiter, Salz-Reich. 7000 Jahre Hallstatt, VPA 2 (Wien, 2008) Seite 133 Abbildung 6. Hallstatt Village & Ossuary Photos: P. McClure Photography ca. 2015.

Bernoulli D, Jenkyns HC (1974) Alpine, Mediterranean, and Central Atlantic Mesozoic facies in relation to the early evolution of the Tethys. Soc Econ Paleont Mineral Spec Publ 19:129–160

Bernoulli D, Jenkyns H (2009) Ancient oceans and continental margins of the Alpine-Mediterranean Tethys: deciphering clues from Mesozoic pelagic sediments and ophiolites. Sedimentology 56:149–190

Wednesday, 9 November 2022

TRACKING THROUGH THE TRIASSIC

Grambergia sp. Middle Triassic Ammonoid of  BC, Canada
In the early 1980s, Tim Tozer, Geological Survey of Canada was looking at the spread of marine invertebrate fauna in the Triassic of North America. 

In the western terranes of the Cordillera, marine faunas from southern Alaska and Yukon to Mexico are known from the parts that are obviously allochthonous with regard to the North American plates.

Lower and upper Triassic faunas of these areas, as well as some that are today up to 63 ° North, have the characteristics of the lower palaeo latitudes. 

In the western Cordillera, these faunas of the lower paleo latitudes can be found up to 3,000 km north of their counterparts on the American plate. This indicates a tectonic shift of significant magnitude. There are marine triads on the North American plate over 46 latitudes from California to Ellesmere Island. 

For some periods, two to three different faunal provinces can be distinguished. The differences in faunal species are linked, not surprisingly, to their palaeolatitude. They are called LPL, MPL, HPL (lower, middle, higher palaeolatitude).

Nevada provides the diagnostic features of the lower (LPL); northeastern British Columbia that of the middle (MPL) and Sverdrup Basin, the large igneous province on Axel Heiberg Island and Ellesmere Island, Nunavut, Canada near the rifted margin of the Arctic Ocean, that of the higher palaeolatitude (HPL).

A distinction between the provinces of the middle and the higher palaeo-situations can not be made for the lower Triassic and lower Middle Triassic (anise). However, all three provinces can be seen in the deposits of Ladin, Kam and Nor.

In the early 2000s, as part of a series of joint UBC, VIPS and VanPS fossil field trips (and then Chair of the VanPS), I explored much of the lower faunal outcrops of northeastern British Columbia. It was my first time seeing many of British Columbia's Triassic outcrops. Years later, and fueled by seeing paper after paper correlating the faunal assemblages of BC to those of Nevada, I had the very great pleasure of walking through the Nevada strata with John Fam (VanPS, Vice-Chair), Dan Bowen (VIPS, Chair) and Betty Franklin (VIPS, Goddess of Everything and BCPA, Treasurer) — and witnessing first-hand the correlation between the Nevada fauna and those from the Triassic of British Columbia, Canada.

Triassic ammonoids, West Humboldt Mountains, Nevada, USA
The Nevada faunal assemblages are a lovely match. The quality of preservation at localities like Fossil Hill in the Humboldt Mountains of Nevada, perhaps the most famous and important locality for the Middle Triassic (Anisian/Ladinian) of North America, is truly outstanding.

Aside from sheer beauty and spectacular preservation, the ammonoids and belemnites were tucked in cozily with very well preserved ichthyosaur remains.

Tozer's interest in our marine invert friends was their distribution. How and when did certain species migrate, cluster, evolve — and for those that were prolific, how could their occurrence — and therefore significance — aide in an assessment of plate and terrane movements that would help us to determine paleolatitudinal significance. 

I share a similar interest but not exclusive to our cephalopod fauna. The faunal collection of all of the invertebrates holds appeal.

Middle Triassic (Anisian/Ladinian) Fauna
This broader group held an interest for J.P. Smith who published on the marine fauna in the early 1900s based on his collecting in scree and outcrops of the West Humboldt Mountains, Nevada. He published his first monograph on North American Middle Triassic marine invertebrate fauna in 1914.

N. J. Siberling from the US Geological Survey published on these same Nevada outcrops in 1962. His work included nearly a dozen successive ammonite faunas, many of which were variants on previously described species. Both their works would inform what would become a lifelong piecing together of the Triassic puzzle for Tozer.

If one looks at the fauna and the type of sediment, the paleogeography of the Triassic can be interpreted as follows: a tectonically calm west coast of the North American plate that bordered on an open sea; in the area far from the coast, a series of volcanic archipelagos delivered sediment to the adjacent basins. 

Some were lined or temporarily covered with coral wadding and carbonate banks. Deeper pools were in between. The islands were probably within 30 degrees of the triadic equator. They moved away from the coast up to about 5000 km from the forerunner of the East Pacific Ridge. The geographical situation west of the back was probably similar.

Jurassic and later generations of the crust from near the back have brought some of the islands to the North American plate; some likely to South America; others have drifted west, to Asia. There are indications that New Guinea, New Caledonia and New Zealand were at a northern latitude of 30 ° or more during the Triassic period.

The terranes that now form the western Cordillera were probably welded together and reached the North American plate before the end of the Jurassic period.

Marine Triassic occurs on the North American Plate over a latitudinal spread of 46 degrees, from California to Ellesmere Island. At some intervals of time faunas on the Plate permit the discrimination of two or three provinces with distinctively different coeval faunas. 

The faunal differences are evidently related to paleolatitude and the provinces are designated LPL, MPL, HPL (low, mid, high paleolatitude). Nevada provides the diagnostic characters of the LPL province; northeastern British Columbia the MPL; the Sverdrup Basin the HPL. In the Lower Triassic and early Middle Triassic (Anisian), the distinction between the MPL and HPL provinces cannot be made. All three provinces are recognized in the Ladinian, Carnian and Norian deposits.

Juvavites sp. Geological Survey of Canada. Photo: John Fam
In the western tracts of the Cordillera, the part formed of suspect terranes, apparently allochthonous with respect to the North American Plate, marine faunas are known all the way from southern Alaska and Yukon to Mexico.

Lower and Upper Triassic faunas from these terranes, including some which today are at 63 degrees north, have the characters of the LPL province.

Middle Triassic faunas from the terranes, as presently known, do not contribute significant data. In the terranes of the Western Cordillera, LPL faunas were now up to 3,000 km north of their counterparts on the American Plate. Through the fossil fauna assemblages, we can see this level of tectonic displacement.

Taking into account the faunas and the nature of the rocks, the Triassic paleogeography is interpreted as a tectonically quiet west shore for the North American Plate, bordered by an open sea or ocean; then, well off-shore, a series of volcanic archipelagos shedding sediment into adjacent basins. Some were fringed or intermittently covered by coralline shoals and carbonate banks. Deeper basins were in between. The islands probably were within 30 degrees of the Triassic equator and extended offshore for about 5000 km, to the spreading ridge directly ancestral to the East Pacific Rise. The geography west of the spreading ridge was probably comparable.

Jurassic and later generation of crust at the ridge had driven some of the islands into the North American Plate; some probably to South America; others have gone west to Asia. Evidence is given that northern New Guinea, New Caledonia and New Zealand may have been at a north latitude of 30 degrees or more in the Triassic. The terranes now forming the Western Cordillera had probably amalgamated, and reached the North American Plate, before the end of the Jurassic.

At the end of the Rhaetian (part of the Triassic period), most of the ammonites had died out. These are the lovely coiled molluscs you often see in museums and gift shops that sell fossils. They are a particular favourite of mine and they are both beautiful and useful to tell us much about deep time. The Hettangian, a rather poorly understood 3 million year time interval followed the Triassic-Jurassic mass extinction event.

During the Hettangian, the new or  Neoammonites developed quite quickly. Within a million years, a fairly large, diverse selection of genera and species had risen to fill the void. The gap created by the Triassic-Jurassic extinction event was re-filled and our ability to "read the rocks' to understand their continued movement through tectonic plate shifting recommenced.

Alsatites proaries, Hettangian Ammonite
It is during the Hettangian that the smooth shelled ammonite genus Psiloceras first appears. They span the time between 201.3 ± 0.2 Ma and 199.3 ± 0.3 Ma (million years ago). For my European friends, the Hettangian is the time span in which the marine limestone, shales and clay Lias of western Europe were deposited.

This Hettangian ammonite, Alsatites proaries, is a lovely example of the cephalopods cruising our ancient oceans at that time. Alsatites is an extinct genus of cephalopod belonging to the Ammonite subclass. They lived during the Early Jurassic, Hettangian till the Sinemurian and are generally extremely evolute, many whorled with a broad keel. Or, as described by one of my very young friends, he looks like a coiled snake you make in pottery class.

The Hettangian is an interesting little period of our history. It spans the time between 201.3 ± 0.2 Ma and 199.3 ± 0.3 Ma (million years ago). For my European friends, the Hettangian is the time in which the marine limestone, shales and clay Lias of western Europe were deposited. In British Columbia, Canada, we see the most diverse middle and late Hettangian (Early Jurassic) ammonite assemblages in the Queen Charlotte Islands (Haida Gwaii), an archipelago about 50 km off British Columbia's northern Pacific coast. In total, 53 ammonite taxa are described of which Paradasyceras carteri, Franziceras kennecottense, Pleuroacanthites charlottensis, Ectocentrites pacificus and Curviceras haidae are new.

In general, North American Early Jurassic ammonites are of Tethyan affinity or endemic to the eastern Pacific. For this reason, a separate zonation for the Hettangian and Sinemurian of the Western Cordillera of North America was established. Taylor et al. (2001), wrote up and published on much of this early research though, at the time, very little Canadian information was included.

Longridge, L. M., et al. “Three New Species of the Hettangian (Early Jurassic) Ammonite Sunrisites from British Columbia, Canada.” Journal of Paleontology, vol. 82, no. 1, 2008, pp. 128–139. JSTOR, www.jstor.org/stable/20144175. Accessed 27 Jan. 2020.

Tozer, ET (Tim): Marine Triassic faunas of North America: Their significance for assessing plate and terrane movements. Geol Rundsch 71, 1077-1104 (1982). https://doi.org/10.1007/BF01821119

Danner, W. (Ted): Limestone resources of southwestern British Columbia. Montana Bur. Mines & Geol., Special publ. 74: 171-185, 1976.

Davis, G., Monger, JWH & Burchfiel, BC: Mesozoic construction of the Cordilleran “collage”, central British Columbia to central California. Pacific Coast Paleography symposium 2, Soc. Economic Paleontologists and Mineralogists, Los Angeles: 1-32, 1978.

Gibson, DW: Triassic rocks of the Rocky Mountain foothills and front ranges of northeastern British Columbia and west-central Alberta. Geol. Surv. Canada Bull. 247, 1975.

Photo of the large belemnite (Atractites sp?) and ammonites (Sunrisites & Badouxia) from the Lower Jurassic (Late Hettangian), Last Creek Formation (Castle Pass member), Taseko Lakes area, British Columbia, Canada in the collection of the deeply awesome John Fam.

Photo: A drawer of Juvavites sp. in the collections of the Geological Survey of Canada. These rarely seen Upper Triassic (Carnian to Norian) ammonoids were collected over many decades by geologists of the Geological Survey of Canada from Northeastern British Columbia. Photo care of the deeply awesome John Fam.

Photo: Grambergia sp. from the Early Anisian (Middle Triassic) ammonoid biostratigraphy of northeastern British Columbia, Canada. Collection of Fossil Huntress.

Photo: Alsatites proaries, Coll. Reiter, Neoammoniten, 30 July 2011, 19:26:10

Monday, 7 November 2022

OH, SHINY. FOSSILS PRESERVED IN PYRITE

We sometimes find fossils preserved by pyrite. They are prized as much for their pleasing gold colouring as they are for their scientific value as windows into the past. 

Sometimes folk add a coating of brass to increase the aesthetic appeal — a practice is frowned upon in paleontological communities.

Pyrite, sometimes called Fool's Gold, is a brass-yellow mineral with a bright metallic lustre. I popped a photo of some pyrite below so you can see the characteristic shape of its cubic crystal system.

Fool's Gold has a chemical composition of iron sulfide (FeS2) and is the most common sulfide mineral. It forms at high and low temperatures usually in small quantities, in igneous, metamorphic, and sedimentary rocks. If these sulfide minerals are close at hand when a fossil is forming, they can infuse specimens, replacing their mineral content to beautiful effect.

When we find a fossil preserved with pyrite, it tells us a lot about the conditions on the seabed where the organism died. Pyrite forms when there is a lot of organic carbon and not much oxygen in the vicinity. 

The reason for this is that bacteria in sediment usually respire aerobically (using oxygen), however, when there is no oxygen, they respire without oxygen (anaerobic) typically using sulphate. 

Sulphate is a polyatomic anion with the empirical formula SO2−4. It is generally highly soluble in water. Sulfate-reducing bacteria, some anaerobic microorganisms, such as those living in sediment or near deep-sea thermal vents, use the reduction of sulfates coupled with the oxidation of organic compounds or hydrogen as an energy source for chemosynthesis.

The sulfide mineral Pyrite, FeS2
High quantities of organic carbon in the sediment form a barrier to oxygen in the water. This also works to encourage anaerobic respiration. Anaerobic respiration using sulphate releases hydrogen sulphide, which is one of the major components in pyrite. 

So, when we find a fossil preserved in pyrite, we know that it died and was buried in sediment with low quantities of oxygen and high quantities of organic carbon. 

If you have pyrite specimens and want to stop them from decaying, you can give them a 'quick' soak in water (hour max) then wash them off, dry thoroughly in a warm oven. 

Cool, then soak in pure acetone for a couple of days. Then soak in paraloid, a thermoplastic resin surface coating or acetone for a couple of days. Keep in a sealed container with a desiccant pack afterwards to keep them dry — or leave them out on display to enjoy knowing that the decay will come in time. We do this with cut flowers so why not fossils sometimes.

I have a friend who gives her pyrite fossils on display a quick thumb wipe with vasoline or petroleum jelly. I'm not sure if the hydrocarbons there will play nice over time but it will act as a protective barrier.  

Saturday, 5 November 2022

RAINBOW AMMONITE: THE UNLIKELY LANDLORD

What you are seeing here is a protuberance extruding from the venter of Quenstedtoceras cf. leachi (Sowerby). It is a pathology in the shell from hosting immature bivalves that shared the seas with these Middle Jurassic, Upper Callovian, Lamberti zone fauna from the Volga River basin. The collecting site is the now inactive Dubki commercial clay quarry and brickyard near Saratov, Russia. 

The site has produced thousands of ammonite specimens. A good 1,100 of those ended up at the Black Hills Institute of Geological Research in Hill City, South Dakota. 

Roughly 1,000 of those are Quenstedtoceras (Lamberticeras) lamberti and the other 100 are a mix of other species found in the same zone. These included Eboraciceras, Peltoceras, Kosmoceras, Grossouvria, Proriceras, Cadoceras and Rursiceras

What is especially interesting is the volume of specimens — 167 Quenstedtoceras (Lamberticeras) lamberti and 89 other species in the Black Hills collection — with healed predation injuries. It seems Quenstedtoceras (Lamberticeras) lamberti are the most common specimens found here and so not surprisingly the most common species found injured. Of the 1,000, 655 of the Quenstedtoceras (Lamberticeras) lamberti displayed some sort of deformation or growth on the shell or had grown in a tilted manner. 

Again, some of the Q. lamberti had small depressions in the centre likely due to a healed bite and hosting infestations of the immature bivalve Placunopsis and some Ostrea

The bivalves thrived on their accommodating hosts and the ammonites carried on, growing their shells right up and over their bivalve guests. This relationship led to some weird and deformities of their shells. They grow in, around, up and over nearly every surface of the shell and seem to have lived out their lives there. It must have gotten a bit unworkable for the ammonites, their shells becoming warped and unevenly weighted. Over time, both the flourishing bivalves and the ammonite shells growing up and over them produced some of the most interesting pathology specimens I have ever seen.    

In the photo here from Emil Black, you can see some of the distorted shapes of Quenstedtoceras sp. Look closely and you see a trochospiral or flattened appearance on one side while they are rounded on the other. 

All of these beauties hail from the Dubki Quarry near Saratov, Russia. The ammonites were collected in marl or clay used in brick making. The clay particles suggest a calm, deep marine environment. One of the lovely features of the preservation here is the amount of pyrite filling and replacement. It looks like these ammonites were buried in an oxygen-deficient environment. 

The ammonites were likely living higher in the water column, well above the oxygen-poor bottom. An isotopic study would be interesting to prove this hypothesis. There's certainly enough of these ammonites that have been recovered to make that possible. It's estimated that over a thousand specimens have been recovered from the site but that number is likely much higher. But these are not complete specimens. We mostly find the phragmocones and partial body chambers. Given the numbers, this may be a site documenting a mass spawning death over several years or generations.

If you fancy a read on all things cephie, consider picking up a copy of Cephalopods Present and Past: New Insights and Fresh Perspectives edited by Neil Landman and Richard Davis. Figure 16.2 is from page 348 of that publication and shows the hosting predation quite well. 

Photos: Courtesy of the deeply awesome Emil Black. These are in his personal collection that I hope to see in person one day. 

It was his sharing of the top photo and the strange anomaly that had me explore more about the fossils from Dubki and the weird and wonderful hosting relationship between ammonites and bivalves. Thank you, my friend!

Wednesday, 19 October 2022

DRIFTWOOD CANYON FOSSIL BEDS / KUNGAX

White Eared Puffbird, Nystalus chacuru
Driftwood Canyon Provincial Park 

Driftwood Canyon Provincial Park covers 23 hectares of the Bulkley River Valley, on the east side of Driftwood Creek, a tributary of the Bulkley River, 10 km northeast of the town of Smithers in northern British Columbia. 

Wet'suwet'en First Nation

The parklands are part of the asserted traditional territory of the Wet'suwet'en First Nation which includes lands around the Bulkley River, Burns Lake, Broman Lake, and François Lake in the northwestern Central Interior of British Columbia. 

The Wetʼsuwetʼen are part of the Dakelh or Carrier First Nation, and in combination with the Babine First Nation are referred to as the Western Carrier. They speak Witsuwitʼen, a dialect of the Babine-Witsuwitʼen language which, like its sister language Carrier, is a member of the Athabaskan family.

Their oral history or kungax recounts a time when their ancestral village, Dizkle or Dzilke, once stood upstream from the Bulkley Canyon. This cluster of cedar houses on both sides of the river was said to be abandoned because of an omen of impending disaster. The exact location of the village has been lost but their stories live on. 

The neighbouring Gitxsan people of the Hazelton area have a similar tale, though the village in their version is referred to as Dimlahamid or Temlahan. Their house groups include the Gilseyhu or Big Frog Clan, the Laksilyu or Small Frog Clan, the Tsayu or Beaver Clan, the Gitdumden or Wolf and Bear Clan and the Laksamshu or Fireweed and Owl Clan.

Driftwood Canyon Fossil Beds

Driftwood Canyon's Fossil Beds record life in the earlier portion of the Eocene when British Columbia — and indeed our world — was much warmer than it is today. This site is recognized as one of the world’s most significant fossil beds. It provides us with a fascinating opportunity to understand the area’s evolutionary processes of both geology and biology. The park was created in 1967 by the donation of the land by the late Gordon Harvey (1913–1976) to protect fossil beds on the east side of Driftwood Creek. The beds were discovered around the beginning of the 20th century. 

Metasequoia, the Dawn Redwood
We have found plant, fish and insect fossil here including Metasequoia, the Dawn Redwood, alder, fossil salmon, wasps, water striders and vertebrate material. Bird feathers are infrequently collected from the shales; however, two bird body fossils have been found here.

In 1968, a bird body fossil was collected in the Eocene shales of the Ootsa Lake Group in Driftwood Canyon Provincial Park by Pat Petley of Kamloops. Pat Petley donated the specimen in 2000 to the Thompson Rivers University (TRU) palaeontology collections. This fossil bird specimen is tentatively identified as the puffbird, Piciformes Bucconidae, of the genus Primobucco.

Primobucco is an extinct genus of bird placed in its own family, Primobucconidae. The type species, Primobucco mcgrewi, lived during the Lower Eocene of North America. It was initially described by American paleo-ornithologist Pierce Brodkorb in 1970, from a fossil right-wing, and thought to be an early puffbird. However, the discovery of a further 12 fossils in 2010 indicate that it is instead an early type of roller.

Related fossils from the European Messel deposits have been assigned to the two species P. perneri and P. frugilegus. Two specimens of P. frugilegus have been found with seeds in the area of their digestive tract, which suggests that these birds were more omnivorous than the exclusively predaceous modern rollers. The Driftwood specimen has never been thoroughly studied. If there is a grad student out there looking for a worthy thesis, head on down to the Thompson Rivers University where you'll find the specimen on display.

Another fossil bird, complete with feathers, was collected at Driftwood Canyon in 1970, This one was found by Margret and Albrecht Klöckner who were travelling from Germany. Theirs is a well-travelled specimen, having visited many sites in BC as they toured around, then to Germany and finally back to British Columbia when it was repatriated and donated to the Royal British Columbia Museum in Victoria. I'm not sure if it is still on display or back in collections, but it was lovingly displayed back in 2008. There is a new grad student, Alexis, looking at Eocene bird feathers down at the RBCM, so perhaps it is once again doing the rounds. 

This second bird fossil is of a long-legged water bird and has been tentatively identified by Dr. Gareth Dyke of the University of Southampton as possibly from the order Charadriiformes, a diverse order of small to medium-ish water birds that include 350 species of gulls, plovers, sandpipers, terns, snipes, and waders. Hopefully, we'll hear more on this find in the future.

Tapirs and Tiny Hedgehogs

The outcrops at Driftwood Canyon are also special because they record a record of some of the first fossil mammals ever to be found in British Columbia at this pivotal point in time. Wee proto-hedgehogs smaller than your thumb lived in the undergrowth of that fossil flora. They shared the forest floor with an extinct tapir-like herbivore in the genus Heptodon that looked remarkably similar to his modern, extant cousins but lacked their pronounced snout (proboscis). I'm guessing that omission made him the more fetching of his lineage.

In both cases, it was a fossilized jaw bone that was recovered from the mud, silt and volcanic ash outcrops in this ancient lakebed site. And these two cuties are significant— they are the very first fossil mammals we've ever found from the early Eocene south of the Arctic.

How can we be sure of the timing? The fossil outcrops here are found within an ancient lakebed. Volcanic eruptions 51 million years ago put loads of fine dust into the air that settled then sank to the bottom of the lake, preserving the specimens that found their way here — leaves, insects, birds, mammals.

 As well as turning the lake into a fossil making machine (water, ash, loads of steady sediment to cover specimens and stave off predation...) the volcanic ash contains the very chemically inert (resistant to mechanical weathering) mineral zircon which we can date with uranium/lead (U/Pb). 

The U/Pb isotopic dating technique is wonderfully accurate and mighty helpful in dating geologic events from volcanic eruptions, continental movements to mass extinctions. This means we know exactly when these lovelies were fossilized and, in turn, their significance.

What To Know Before You Go

If you fancy a visit to Driftwood Canyon Park, the park is accessible from Driftwood Road from Provincial Highway 16. You are welcome to view and photograph the fossils found here but collecting is strictly forbidden. 

Driftwood Canyon is recognized as one of the world’s most significant fossil beds. It provides park users with a fascinating opportunity to understand the area’s evolutionary processes of both geology and biology. The day-use area is open from May 15 to September 2. There is a short, wheelchair-accessible interpretative trail that leads from the parking are to the fossil beds. Pets are welcome on leash. Signs along the trail provide information on fossils and local history. 

Below a cliff face at the end of the trail is a viewing area that has interpretive information and viewing area overlooking Driftwood Creek.

This park proudly operated by Mark and Anais Drydyk
Email: kermodeparks@gmail.com / Tel: 1 250 877-1482 or 1 250 877-1782

Driftwood Canyon Provincial Park Brochure: 
https://bcparks.ca/explore/parkpgs/driftwood_cyn/driftwood-canyon-brochure.pdf?v=1638723136455


Tuesday, 18 October 2022

A TASTE FOR STUDIES

Chelonia. Schildkröten by Ernst Haeckel, 1904
Care for some tarantula with that walrus? No? how about some Woolly mammoth?

While eating study specimens is not de rigueur today, it was once common practice for researchers in the 1700-1880s. 

The English naturalist, Charles Darwin belonged to an elite men's club dedicated to tasting exotic meats. In his first book, Darwin wrote almost three times as much about dishes like armadillo and tortoise urine as he did on the biogeography of his Galapagos finches. 

From his great love of gastronomy, I am surprised any of his tasty specimens made it back from his historic voyage on the HMS Beagle — particularly the turtles.

One of the most famous scientific meals occurred one Saturday evening on the 13th of January, 1951. This was at the 47th Explorers Club Annual Dinner (ECAD) when members purportedly dined on a frozen woolly mammoth. 

Commander Wendell Phillips Dodge was the promotor of the banquet. He sent out press notices proclaiming the event's signature dish would be a selection of prehistoric meat. Whether Dodge did this simply to gain attendees or play a joke remains a mystery. 

The prehistoric meat was supposedly found at Woolly Cove on Akutan in the Aleutians Islands of Alaska, USA, by the eminent polar explorers' Father Bernard Rosecrans Hubbard, American geologist, explorer sometimes called the Glacier Priest, and polar explorer Captain George Francis Kosco of the United States Navy.

Fried Tarantula & Goat Eyeballs

This much-publicized meal captured the public’s imagination and became an enduring legend and source of pride for the Club, popularizing an annual menu of exotics that continues today. The Club is well-known for its notorious hors d’oeuvres like fried tarantulas and goat eyeballs as it is for its veritable whose who of notable members — Teddy Roosevelt, Neil Armstrong, Buzz Aldrin, Roy Chapman Andrews, Thor Heyerdahl, James Cameron.

The Yale Peabody Museum holds a sample of meat preserved from the 1951 meal, interestingly labelled as a South American Giant Ground Sloth, Megatherium, not Mammoth. The specimen of meat from that famous meal was originally designated BRCM 16925 before a transfer in 2001 from the Bruce Museum to the Yale Peabody Museum of Natural History (New Haven, CT, USA) where it gained the number YPM MAM 14399.

The specimen is now permanently deposited in the Yale Peabody Museum with the designation YPM HERR 19475 and is accessible to outside researchers. The meat was never fixed in formalin and was initially stored in isopropyl alcohol before being transferred to ethanol when it arrived at the Peabody Museum. DNA extraction occurred at Yale University in a clean room with equipment reserved exclusively for aDNA analyses.

In 2016, Jessica Glass and her colleagues sequenced a fragment of the mitochondrial cytochrome-b gene and studied archival material to verify its identity, which if genuine, would extend the range of Megatherium over 600% and alter views on ground sloth evolution. 

Mammoth, Megatherium — Green Sea Turtle

Their results showed that the meat was not Mammoth or Megatherium, but a bit of Green Sea Turtle, Chelonia mydas. So much for elaborate legends. The prehistoric dinner was likely meant as a publicity stunt. 

Glass's study emphasizes the value of museums collecting and curating voucher specimens, particularly those used for evidence of extraordinary claims. Not so long before Glass et al. did their experiment, a friend's mother (and my kayaking partners) served up a venison steak from her freezer to dinner guests in Castlegar that hailed from 1978. Tough? Inedible? I have it on good report that the meat was surprisingly divine.

Reference: Glass, J. R., Davis, M., Walsh, T. J., Sargis, E. J., & Caccone, A. (2016). Was Frozen Mammoth or Giant Ground Sloth Served for Dinner at The Explorers Club?. PloS one, 11(2), e0146825. https://doi.org/10.1371/journal.pone.0146825

Image: Chelonia. Schildkröten by Ernst Haeckel, 1904, Prints & Photographs Division, Library of Congress, LC-DIG-ds-07619.

Join the Explorer's Club

Fancy yourself an explorer who should join the club? Here is a link to their membership application. The monied days of old are still inherent, but you will be well pleased to learn you can now join for as little as $50 US.

Link: https://www.explorers.org/wp-content/uploads/Membership-Application_2021-11-19.pdf

Sunday, 16 October 2022

VANCOUVER ISLAND'S HASLAM FORMATION

Steller's Jay, Cyanocitta stelleri
One of the classic Vancouver Island fossil localities is the Santonian-Maastrichtian, Upper Cretaceous Haslam Formation Motocross Pit near Brannen Lake, Nanaimo, British Columbia, Canada.

The quarry is no longer active as such though there is a busy little gravel quarry a little way down the road closer to Ammonite falls near Benson Creek Falls.

Today it is an active motocross site and remains one of the classic localities of the Nanaimo Group. We find well-preserved nautiloids and ammonites — Canadoceras, Pseudoschloenbachia, Epigoniceras — the bivalves — Inoceramus, Sphenoceramus— gastropods, and classic Nanaimo Group decapods — Hoploparia, Linuparus. We also find fossil fruit and seeds which tell the story of the terrestrial history of Vancouver Island.

Upper Cretaceous Haslam Formation Motocross Pit near Brannen Lake
It was John Fam, Vice-Chair, Vancouver Island Paleontological Society (VanPS), who originally told me about the locality. John is one of the most delightful and knowledgeable people you'd be well-blessed to meet.

While he lived on Vancouver Island, he was an active member of the VanPS back when I was Chair. Several of the best joint VIPS/VanPS paleontological expeditions were planned with or instigated by his passion for fossils. I tip my hat to him for his passion and shared love of all things paleo.

John grew up 15 minutes from the motocross locality and used to collect there a few times a week with his father. John has wonderful parents and since marrying his childhood sweetheart, the amazing Grace, those excellent genetics, curiosity and love of fossils are now being passed to a new generation. It's lovely to see John and Grace continuing tradition with two boys of their own.

I met John way back then and did an overnight at his parent's house the Friday before a weekend field trip to Jurassic Point. It was a joy to have him walk me through his collections and tell his stories from earlier years. After learning about the site from John, I headed up to the Motocross Pit with my Uncle Doug. He was a delightful man who grew up on the coast and had explored much of it but not the fossil site just 10-minutes from his home. It was wonderful to walk through time with him so many years ago and then again solo this past year with sadness in my belly that one of the best I've ever known has left this Earth.

Upper Cretaceous Haslam Formation Motocross Pit near Brannen Lake
There were some no trespassing signs up but no people around, so I walked the periphery looking for the bedrock of the Haslam.

The rocks we find here were laid down south of the equator as small, tropical islands. They rode across the Pacific heading north and slightly east over the past 80 million years to where we find them today.

Jim Haggart and Peter Ward have done much to increase our understanding of the molluscan fauna of the Nanaimo Group. Personally, both personify the charming Indiana Jones school of rugged manly palaeontologists you picture in popular film. Professionally, their singular contributions and collaborative efforts have helped shape our understanding of the correlation of Nanaimo Group fauna to those we find in the Gulf Islands of British Columbia and down in the San Juan Islands of Washington State.

Their work builds on the work of Usher (1952), Matsumoto (1959a, 1959b) and Mallory (1977). A healthy nod goes out to the work of Muller and Jeletzky (1970) for untangling the lithostratigraphic and biostratigraphic foundation for our knowledge of the Nanaimo Group.

Candoceras yokoyama, Photo: John Fam, VanPS
As I walked along the bedrock of the Haslam, a Steller's Jay, Cyanocitta stelleri, followed me from tree to tree making his guttural shook, shook, shook call. Instructive, he seemed to be encouraging me, timing his hoots to the beat of my hammer. Vancouver Island truly has glorious flora and fauna.

Fancy some additional reading? Check out a paper published in the Journal of Paleontology back in 1989 by Haggard and Ward on new Nanaimo Group Ammonites from British Columbia and Washington State.

In it, they look at the ammonite species Puzosia (Mesopuzosia) densicostata Matsumoto, Kitchinites (Neopuzosia) japonicus Spath, Anapachydiscus cf. A. nelchinensis Jones, Menuites cf. M. menu (Forbes), Submortoniceras chicoense (Trask), and Baculites cf. B. boulei Collignon are described from Santonian--Campanian strata of western Canada and northwestern United States.

Stratigraphic occurrences and ranges of the species are summarized and those taxa important for correlation with other areas in the north Pacific region and Late Cretaceous ammonite fauna of the Indo-Pacific region. Here's the link: https://www.jstor.org/stable/1305358?seq=1

Peter Ward is a prolific author, both of scientific papers and more popularized works. I highly recommend his book Gorgon: Paleontology, Obsession, and the Greatest Catastrophe in Earth's History. It is an engaging romp through a decade's research in South Africa's Karoo Desert.

Photo: Candoceras yokoyamai from Upper Cretaceous Haslam formation (Lower Campanian) near Nanaimo, British Columbia. One of the earliest fossils collected by John Fam (1993). Prepared using only a cold chisel and hammer. Photo & collection of John Fam, VIPS.

Tuesday, 11 October 2022

CRANBROOK EAGER FORMATION: TUZOIA

This specimen of the arthropod Tuzoia sp. is from the Lower Cambrian Eager Formation of British Columbia. 

Tuzoia is an extinct genus of large bivalved arthropod known from Early to Middle Cambrian marine environments in what is now the Burgess Shale, Emu Bay Shale, Kaili, the Rockslide Formation, the Spence Shale, Wheeler Formation, and Marjum Formation, and the Kinzers Formation. 

As you can see here, they are also found in the Lower Cambrian Eager Formation near Cranbrook British Columbia. 

This particular specimen is from the Rifle Range outcrop near Cranbrook where you can also find numerous fragments and complete specimens of the olenellid trilobites Ollenellus sp. and the larger, more robust Wanneria dunnae, along with Mesonacis eagerensis (Best, 1952).

The site outcrops at a few locations as you head east out of Cranbrook towards Fort Steele. The first trilobites were discovered with the building of the Kootenay Highway connecting Cranbrook to Fort Steele and beyond. Several other localities, including the outcrops at the Silhouette Rife Range — which is literally on a Rifle Range where folks go to shoot at things — is a shade older than the Middle Cambrian Burgess Shale but the fauna here is much less varied. 

The site has been known and collected since the 1920s. Back in the day, fossil collecting was a family affair with folks heading out in their lightly coloured finery to picnic and surface collect the eroding exposures. Cranbrook local, Clement Hungerford Pollen was an engineer and avocational palaeontologist. He promoted collecting the exposures of the Eager Formation around 1921. As a pedigreed Englishman of considerable means, he had invested in the Kootenay Central Railway, revitalizing the town by opening up railway access within the region.

Saturday, 3 September 2022

FOSSIL COLLECTING AT THE MYSTERIOUS CREEK FORMATION

Located three hours east of Vancouver, most folks head to Harrison Lake to enjoy its crisp waters, soak in the hot springs, camp or four-wheel-drive immersed in rugged scenery, or look for the elusive Sasquatch reported to live in the area. 

But some come to Harrison Lake and miss the town entirely. Instead, they favour the upper west side of the lake and the fossiliferous bounty found here.

Indeed, this is the perfect location for local citizen scientists to strut their stuff. Harrison is a perfect family day trip, where you can discover wonderful marine fossil specimens as complete or partially crushed fossilized shells embedded in rock. 

Amazingly, we can find them at all. These beauties range in age from Jurassic to Cretaceous, with most being Lower Callovian, meaning the ammonites here swam our ancient oceans more than 160 million years ago. 

The area around Harrison Lake has been home to the Sts’ailes, a sovereign Coast Salish First Nation for thousands of years. Sts’ailes’ means, “the beating heart,” and it sums up this glorious wilderness perfectly. They describe their ancient home as Xa’xa Temexw or Sacred Earth. 

With the settling of Canada, Geologists began exploring the area in the 1880s, calling upon the Sts’ailes to help them look for coal and a route for the Canadian Pacific Railway. Coal was the aim, but happily, they also found fossils. Sacred Earth, indeed.  

Belemnite Fossils
In my favourite outcrops, you can find large, smooth inflated Jurassic ammonites along with their small grey and brown cousins. 

Further up the road, you will see Cretaceous cigar-shaped squid-like cephalopods called Belemnites, and the bivalve (clam) Buchia — gifts deposited by glaciers. Here are the most common.

Ammonites

Almost all of the ammonite specimens found near Harrison Lake are the toonie sized Cadoceras (Paracadoceras) tonniense with well-preserved outer whorls but flattened inner whorls. We find semi-squished elliptical specimens here, too. If you see a large, smooth, inflated grapefruit-sized ammonite, you are holding a rare prize — a Cadoceras comma ammonite, the macroconch or female of the species.  

Ammonites were predatory, squid-like creatures that lived inside coil-shaped shells. Like other cephalopods, ammonites had sharp, beak-like jaws inside a ring of squid-like tentacles that extended from their shells. They used these tentacles to snare prey — plankton, vegetation, fish and crustaceans — similar to the way a squid or octopus hunts today.

Within their shells, ammonites had a number of chambers called septa filled with gas or fluid, and they were interconnected through a wee air tube. By pushing air in or out, they were able to control their buoyancy. 

These small but mighty marine predators lived in the last chamber of their shell and continuously built new shell material as they grew. As they added each new chamber, they would move their squid-like body down to occupy the final outside chamber.

Interestingly, ammonites from Harrison Lake are quite similar to the ones found within the lower part of the Chinitna Formation near Cook Inlet, Alaska, and Jurassic Point, Kyuquot, on the west coast of Vancouver Island — some of the most beautiful places on Earth. 

Buchia (bivalve) Clams

The bivalve or clam Buchia are commonly found at Harrison Lake. You will see them cemented together en masse. . They populated Upper Jurassic–Lower Cretaceous waters like a team sport. When they thrived, they really thrived, building up large coquinas of material. Large boulders of Buchia cemented together en masse hitched a ride with the glaciers and were deposited around Harrison Lake. Some kept going and we find similar erratics or glacier-deposited boulders as far south as Washington state. 

Buchia is used as Index Fossils. Index fossils help us to figure out the age of the rock we are looking at because they are abundant, populate an area en masse, and then die out quickly. In other words, they make it easy to identify a geologic time span.

So what does this mean to you? Now, when you are out and about with friends and discover rocks with Buchia, or made entirely of Buchia, you can say, “Oh, this looks to be Upper Jurassic or Lower Cretaceous. Come take a look! We're likely the first to lay eyes on this little clam since dinosaurs roamed the Earth.” 

Fossil Collecting at Harrison Lake Fossil Field Trip — Getting there

This Harrison Lake site is a great day trip from Vancouver or the Fraser Valley. You will need a vehicle with good tires for travel on gravel roads. Search out the route ahead of time and share your trip plan with someone you trust. If you can pre-load the Google Earth map of the area, you will thank yourself. 

Heading east on from Vancouver, it will take you 1.5-2 hours to reach Harrison Mills. 

Access Forestry Road #17 at the northeast end of the parking lot from the Sasquatch Inn at 46001 Lougheed Hwy, Harrison Mills. From there, it will take about an hour to get to the site. Look for signs for the Chehalis River Fish Hatchery to get you started. 

Drive 30 km up Forestry Road #1, and stop just past Hale Creek at 49.5° N, 121.9° W (paleo-coordinates 42.5° N, 63.4° W) on the west side of Harrison Lake. You will see Long Island to your right. 

The first of the yummy fossil exposures are just north of Hale Creek on the west side of the road. Keep in mind that this is an active logging road, so watch your kids and pets carefully. Everyone should be wearing something bright so they can be easily spotted.

How to Spot the Fossils

The fossils here are easily collected—look in the bedrock and in the loose material that gathers in the ditches. Specimens will show up as either dark grey, grey-brown or black. Look for the large, dark-grey boulders the size of smart cars packed with Buchia. 

And while you are at it, be on the lookout for anything that looks like bone. This site is also ripe for marine reptiles—think plesiosaur, mosasaur and elasmosaur. As a citizen scientist and budding palaeontologist, you might just find something new!

What to Know Before You Go

Fill your gas tank and pack a tasty lunch. As with all trips into British Columbia's wild places, dress for the weather. You will need hiking boots, rain gear, gloves, eye protection, and a good geologic hammer and rock (cold) chisel. 

Wear bright clothing and keep your head covered. Slides are common, and you may start a few if you hike the cliffs. If you are with a group, those collecting below may want to consider hardhats in case of rockfall — chunks of rock the size of your fist up to the size of a grapefruit. They pack a punch. 

Bring a colourful towel or something to put your keepers on. Once you set rock down, it can be hard to find again given the terrain. I take the extra precaution of spraying the ends of my hammers and chisels with yellow fluorescent paint, as I have lost too many in the field. You will also want to bring a camera for the blocks of Buchia that are too big to carry home. 

Identifying Your Treasures

When you have finished for the day, compare your treasures to see which ones you would like to keep. In British Columbia, you are a steward of the fossil, which means they belong to the province, but you can keep them safe. You are not allowed to sell or ship them outside British Columbia without a permit. 

Once you get home, wash and identify your finds. Harrison Lake does not have a large variety of fossil fauna, so this should not be difficult. If your find is coiled and round, it is an ammonite. If it is long and straight, it is a belemnite. And if it looks like a wee fat baby oyster, it is Buchia. This is not always true, but mostly true.

What about collecting fossils in all seasons?. Everyone has a preference. I prefer not to collect in the snow, but I have done it. While sunny days are lovely, it can also be easier to see the specimens when the rock is wet. So, do we do this in the rain? Heck, yeah! 

In torrential rain? 

Yes — once you are hooked, but for your casual friends or the kiddos, the answer is likely no. Choose your battles. They may come with you, but a cold day getting soaked is no fun. 

In time, you will find your inner fossil geek — probably with your first find. And that's just the tip of the iceberg. First, it will be you, then your kids, your friends and then your neighbour. Once you start, it is easy to get hooked. Fossil addiction is real, and the only cure is to get out there and do it some more. You've got this!

References and further information:

A. J. Arthur, P. L. Smith, J. W. H. Monger and H. W. Tipper. 1993. Mesozoic stratigraphy and Jurassic palaeontology west of Harrison Lake, southwestern British Columbia. Geological Survey of Canada Bulletin 441:1-62

R. W. Imlay. 1953. Callovian (Jurassic) ammonites from the United States and Alaska Part 2. The Alaska Peninsula and Cook Inlet regions. United States Geological Survey Professional Paper 249-B:41-108

An overview of the tectonic history of the southern Coast Mountains, British Columbia; Monger, J W H; in, Field trips to Harrison Lake and Vancouver Island, British Columbia; Haggart, J W (ed.); Smith, P L (ed.). Canadian Paleontology Conference, Field Trip Guidebook 16, 2011 p. 1-11 (ESS Cont.# 20110248).


Friday, 2 September 2022

FOSSIL FLORA AND FAUNA OF MADAGASCAR

Aioloceras besairiei (Collingnon, 1949)
A stunning example of the internal suturing with calcite infill in this sliced Aioloceras besairiei (Collingnon, 1949) ammonite from the Upper Cretaceous (Lower Albian) Boeny region of Madagascar. 

This island country is 400 kilometres off the coast of East Africa in the Indian Ocean and a wonderful place to explore off the beaten track.

Madagascar has some of the most spectacular of all the fossil specimens I have ever seen. This beauty is no exception. The shell has a generally small umbilicus, arched to acute venter, and typically at some growth stage, falcoid ribs that spring in pairs from umbilical tubercles, usually disappearing on the outer whorls. I had originally had this specimen marked as a Cleoniceras besairiei, except Cleoniceras and Grycia are not present in Madagascar. 

This lovely, seen in cross-section, is now far from home and in the collection of a wonderful friend. It is an especially lovely example of the ammonite, Aioloceras besairiei, making it a beudanticeratinae. Cleoniceras and Grycia are the boreal genera. If you'd like to see (or argue) the rationale on the name, consider reading Riccardi and Medina's riveting work from back in 2002, or Collingnon from 1949.

The beauty you see here measures in at a whopping 22 cm, so quite a handful. This specimen is from the youngest or uppermost subdivision of the Lower Cretaceous. I'd originally thought this locality was older, but dating reveals it to be from the Lower Albian, so approximately 113.0 ± 1.0 Ma to 100.5 ± 0.9 Ma.

Aioloceras are found in the Cretaceous of Madagascar at geo coordinates 16.5° S, 45.9° E: paleo-coordinates 40.5° S, 29.3° E.; and in four localities in South Africa: at locality 36, near the Mzinene River at 28.0° S, 32.3° E: paleo-coordinates 48.6° S, 7.6° E. 

We find them near the Mziene River, at a second locality north of Hluhluwe where the Mzinene Formation overlies the Aptian-Albian Makatini Formation at 28.0° S, 32.3° E: paleo-coordinates 48.6° S, 7.6° E; and at Haughton Z18, on the Pongola River in the Albian III, Tegoceras mosense beds at 27.3° S, 32.2° E: paleo-coordinates 48.0° S, 7.8° E.

If you happen to be trekking to Madagascar, know that it's big. It’s 592,800 square kilometres (or  226,917 square miles), making it the fourth-largest island on the planet — bigger than Spain, Thailand, Sweden and Germany. The island has an interesting geologic history.

Although there has been a geological survey, which was active extending back well into French colonial times, in the non-French-speaking world our geological understanding of the island is still a bit of a mystery. 

Plate tectonic theory had its beginnings in 1915 when Alfred Wegener proposed his theory of "continental drift." 

Wegener proposed that the continents ploughed through the crust of ocean basins, which would explain why the outlines of many coastlines (like South America and Africa) look like they fit together like a puzzle. Half a century after Wegener there is still no agreement as to whether in continental reconstructions Madagascar should be placed adjacent to the Tanzanian coast to the north (e.g., McElhinny and Embleton,1976), against the Mozambique-Natal coast (Flores 1970), or basically left where it is (Kent 1974, Nairn 1978).

There have been few attempts apart from McKinley’s (1960) comparison of the Karoo succession of southwestern Tanzania with that of Madagascar to follow the famous geological precept of “going to sea.” One critical reason is that although there may be a bibliography of several thousand items dealing with Madagascan geology as Besairie (1971) claims, they are items not generally available to the general public. The vital information gained of the geology of the offshore area by post-World War II petroleum exploration has remained largely proprietary. 

Without this data to draw upon, our understanding remains incomplete. I don't actually mind a bit of a mystery here. It is interesting to speculate on how these geologic puzzle pieces fit together and wait for the big reveal. Still, we have good old Besairie from his 1971, Geologie de Madagascar, and a later précis (Besairie, 1973).

We do know that Madagascar was carved off from the African-South American landmass early on. The prehistoric breakup of the supercontinent Gondwana separated the Madagascar–Antarctica–India landmass from the Africa–South America landmass around 135 million years ago. Madagascar later split from India about 88 million years ago, during the Late Cretaceous, so the native plants and animals on the island evolved in relative isolation. 

It is a green and lush island country with more than its fair share of excellent fossil exposures. Along the length of the eastern coast runs a narrow and steep escarpment containing much of the island's remaining tropical lowland forest. If you could look beneath this lush canopy, you'd see rocks of the Precambrian age stretching from the east coast all the way to the centre of the island. The western edge is made up of sedimentary rock from the Carboniferous to the Quaternary.

Red-Tailed Lemurs, Waiwai & Hedgehog
Madagascar is a biodiversity hotspot. Just as Darwin's finches on the Galápagos were isolated, evolving into distinct species (hello, adaptive radiation), over 90% of the wildlife from Madagascar is found nowhere else. 

The island's diverse ecosystems, like so many on this planet, are threatened by Earth's most deadly species, homo sapien sapiens. 

We arrived back in 490 CE and have been chopping down trees and eating our way through the island's tastier populations ever since. Still, they have cuties like this Red-Tailed Lemur. Awe, right?

Today, beautiful outcrops of wonderfully preserved fossil marine fauna hold appeal for me. The material you see from Madagascar is distinctive — and prolific.

Culturally, you'll see a French influence permeating the language, architecture and legal process. There is a part of me that pictures these lovely Lemurs chatting away in French. "Ah, la vache! Regarde le beau fossile, Hérissonne!"

We see the French influence because good 'ol France invaded sleepy Madagascar back in 1883, during the first Franco-Hova War. Malagasy (the local Madagascarian residents) were enlisted as troops, fighting for France in World War I.  During the Second World War, the island was the site of the Battle of Madagascar between the Vichy government and the British. By then, the Malagasy had had quite enough of colonization and after many hiccuping attempts, reached full independence in 1960. Colonization had ended but the tourist barrage had just begun. You can't stop progress.

If you're interested in learning more about this species, check out the Treatise on Invertebrate Paleontology, Part L (Ammonoidea). R.C. Moore (ed). Geological Soc of America and Univ. Kansas Press (1957), p L394. Or head over to look at the 2002 paper from Riccardi and Medina. 2002. Riccardi, A., C. & Medina, F., A. The Beudanticeratinae and Cleoniceratinae (Ammonitina) from the Lower Albian of Patagonia in Revue de Paléobiologie - 21(1) - Muséum d’Histoire Naturelle de la ville de Genève, p 313-314 (=Aioloceras besairiei (COLLIGNON, 1949). You have Bertrand Matrion to thank for the naming correction. Good to have friends in geeky places!

Collignon, M., 1933, Fossiles cenomaniens d’Antmahavelona (Province d’ Analalave, Madagascar), Ann. Geol. Serv. Min. Madagascar, III, 1934 Les Cephalopods du Trias inferieur de Madagascar, Ann. Paleont. XXII 3 and 4, XXII 1.

Besairie, H., 1971, Geologie de Madagascar, 1. Les terrains sedimentaires, Ann. Geol. Madagascar, 35, p. 463.

J. Boast A. and E. M. Nairn collaborated on a chapter in An Outline of the Geology of Madagascar, that is very readable and cites most of the available geologic research papers. It is an excellent place to begin a paleo exploration of the island.

If you happen to parle français, check out: Madagascar ammonites: http://www.ammonites.fr/Geo/Madagascar.htm