Archaeology Podcast Network Features Paleontologist Amy Atwater from Museum of the Rockies

Amy Atwater is the Paleontology Collections Manager/Registrar at the Museum of the Rockies in Bozeman, Montana – and more importantly, is an amazing scientist. Her discussion of archaeology/paleontology, deep time, stratigraphy, etc., with the “cowboys of science” in episode #5 of their Life In Ruins podcast series (embedded below) is a must listen! More information about Amy and her work is also available on the Archaeology Podcast Network’s website: Episode#5

Tolting Around Pseudocraters at Lake Myvatn, Iceland

The Lake Myvatn area, located in northeast Iceland, has an amazing, and truly beautiful, volcanic landscape. This area lies within Iceland’s North Volcanic Zone, which is a part of the Mid-Atlantic Ridge – the spreading rift between the Eurasian and North American plates that slices through Iceland. Lake Myvatn is the fourth largest lake in Iceland, and is quite shallow, with the deepest part being only about 4 meters. This area is also renown for its wetlands and birdlife, with the lake’s numerous bays and its outlet to the north-flowing river Laxa being host to a multitude of birds.

Lake Myvatn, viewed from the lake’s eastern side.
Basaltic landscape in the Hofdi area, on the southeast side of Lake Myvatn. Hofdi is a rocky promontory into Lake Myvatn that affords excellent bird watching.
Lava pillars in the Kálfastrandavogar area, southeastern Lake Myvatn.

My favorite experience at Lake Myvatn was riding an Icelandic horse around the pseudocraters in the Skútustaðagígar area of Lake Myvatn (southwestern part of the lake). Pseudocraters are unusual in that they are rootless volcanic cones that formed in this area about 2300 years ago when basaltic lava flowed over the water-logged lake sediment, resulting in the cones being built from steam exploding through the lava. So -not only did I want to see pseudocraters, but I also wanted to lean how to tolt because this is a natural gait exclusive to Icelandic horses. According to Riding-Iceland.com,

“the Tölt is a natural, fluid gait of the Icelandic Horse, during which at least one foot always touches the ground. Foals often tölt in pastures at an early age. The tölt is an extraordinarily smooth four-beat gait, which allows the rider an almost bounce-free ride, even at 32 kmh (20 mph). “

I contacted Safari Horse Rental (located just off the main road in the Skútustaðagígar area) and set up a two hour ride. Gilli was my guide, and he took me through mostly private land to both look at pseudocraters and to teach me how to tolt. It did take me awhile to understand how to let my horse know it was time to break into the tolting gait, but when we both got it figured out, wow! what a way to see pseudocraters! I’d urge anyone who loves to ride horses to try this!

The start of the pseudocrater exploration ride at Safari Horse Rentals!
A pseudocrater looms ahead of us. The pseudocraters are typically composed of tephra, scoria, and splatter that resulted from basaltic lava flowing over water-logged lake sediments forming steam eruptions that blast through the lava.
The remnants of a pseudocrater becomes a watering hole for the area sheep herds.
Basalt block fences are common on Icelandic farm lands.
This photo shows midges covering a part of a pseudocrater. The midges weren’t numerous when I was at Lake Myvatn, but they periodically emerge by the billions to cover the Lake Myvatn area. In fact, Lake Myvatn means “midge lake” in Icelandic. The midge populations are very closely tied to the Lake Myvatn fishery. Unfortunately, dredging in the lake during the 1960’s for a silicon mining operation has probably caused enough fluctuation in the midge populations to result in the collapse of the fishery. See the following publication for more information on this – High-amplitude fluctuations and alternative dynamical states of midges in Lake Myvatn.

Again – I’ll highly recommend that the best way to view Lake Myvatn’s pseudocraters is by tolting on an Icelandic horse!

An Icelandic Sedimentary Sequence – the Tjornes Pliocene Beds

While I am in awe of Iceland’s mid-Atlantic ridge system volcanics and its glacial geology, I still like to see sediments and fossils. So – as I was doing my pre-trip research into Icelandic geology, I found that there are about 500 meters of Pliocene strata exposed on the west coast of the Tjornes Peninsula in northern Iceland. Needless to say, the Tjornes Peninsula became part of my travels in Iceland.

The best way to access the Tjornes sequence is to go to the Tungulending Guesthouse, which is about 12 km north of Husavik. The turnoff for the guesthouse is just off Highway 85 and signed as shown by the photo below. Of course we missed it and kept driving a few km up the main road before we stopped to ask a local farmer. The farmer knew exactly where we wanted to go and sent us back down the road to Tungulending. Once we saw the Tungulending main sign and then passed the guesthouse gate, we knew we were headed in the right direction.

The Tjornes Pliocene strata contain both marine and continental deposits. The strata sit on the Kaldakvisl lavas while the Hoskuldsvik lavas cap the sedimentary sequence. The Tjornes Formation records a coastal environment that includes estuary-swamp, shallow marine-beach, and swamp-fluvial settings that existed in between the basaltic lava events (Simonarsson and Eriksson, 2008). These strata include a diverse mollusc fauna and recently the oldest marine vertebrate fossil in Iceland, a partial skull from a fossil whale (a large right whale), was also found within the Tjornes Formation (Field and others, 2017). Jonathon Hall, a Doctoral Researcher in the School of Geography, Earth and Environmental Sciences, University of Birmingham – UK, has put together a great leaflet on the geology of the Tjornes Peninsula, and the leaflet content can be found here: Geology of the Tjornes Peninsula.

The road leading down to the Tungulending Guesthouse cuts through the Tjornes sedimentary sequence. Note the car on the road near the guesthouse for scale.
The Tjornes Formation is well exposed in a drainage by the Tungulending Guesthouse.
Mollusc fossil fauna of the Tjornes Formation.
Shelly beds within the Tjornes Formation.
Cross-bedded strata with lenses of shelly beds within the Tjornes Formation.

Even if you are enthralled with Iceland’s volcanic and glacial geology, it is still well worth a look at the Tjornes Formation and a visit to the Tungulending Guesthouse for good conversation and food!

The Tungulending Guesthouse with the Pliocene Tjornes Formation in the background.

Iceland Geology – Snorkeling the Silfra Fissure, Thingvellir National Park

I did a snorkel tour of the Silfra fissure with Dive.is while I was in Iceland a couple weeks ago. That is a very impressive way to view part of the mid-Atlantic ridge system! Here’s what Dive.is says about Silfra that makes it so unique:

Snorkeling the Silfra Fissure in Iceland.

“Silfra is a fissure between the North American and Eurasian tectonic plates in Thingvellir National Park. The rift was formed in 1789 by the earthquakes accompanying the divergent movement of the two tectonic plates . The diving and snorkeling site at Silfra is right where the two continents meet and drift apart about 2 cm per year. Silfra is the only place in the world where you can dive or snorkel directly in a crack between two tectonic plates. The earthquakes of 1789 opened up several fissures in the Thingvellir area, but the Silfra fissure cut into the underground spring filled with glacial meltwater from the nearby Langjökull glacier.”

My Silfra snorkel group starting out in the fissure with our guide Jake from Dive.is.

There are 6 people to a group for the snorkel tour, with each group accompanied by a guide from Dive.is. Jake was our guide and he was great! The tour is simply snorkeling through basalt and more basalt, but with the water clarity, the colors are beautiful. There is also one place where you can stretch across the fissure and basically touch both plates.

The start of the snorkel tour where the entrance platform can be seen in the background.
The stretch between plates…
This is where basalt really looks grand!
Near the end of the snorkel tour, the fissure opens into a shallow lagoonal area.
The colors in the sandy lagoon are just as spectacular as elsewhere in the fissure. The exit platform can be seen in the distance.
The end of the snorkel tour – ours was a great weather day, so even though the fissure water is cold (we all wear dry suits with long underwear and two pairs of wool socks), I could have snorkeled around the lagoon for a long time.

I also took video while I was snorkeling, so am inserting a clip from the first part of the snorkel tour at the end of this blog. The video clip includes the time when we all get geared up, have our gear checked, and then flipper-walk down the entrance ramp, into the water. We all have to do a flip over to our back once we’re in the water, just to make sure we can maneuver once we’re in the water. The clip continues on as we snorkel through the first several minutes of exploring the fissure. At the end of the snorkel tour, we hike back to where the Dive.is vans/equipment are. After taking off our gear – which getting off the dry suit is somewhat of a challenge – we have hot chocolate and cookies. Because the weather was so nice, it was a pleasurable experience to stand around and feast. But – we were told that in the wintertime the guides take the hot water that is suppose to be used for the hot chocolate and it pour down the snorkelers’ necks so the dry suits can be pulled off. Glad I opted for late May to do this!

Yellowstone To Southwest Montana Autumn Field Photo Snaps

Montana’s autumn is my favorite time of the year to do field work. Daytime temperatures are usually cool enough to encourage one to keep moving and the lighting is simply gorgeous. It is also one of the best times to visit areas in and around Yellowstone National Park (YNP) because most of the tourists have gone home. So no huge bear traffic jams or jostling for parking spots at the better known thermal spots in YNP and surrounding environs – it’s just a wonderfully introspective time for field forays. What follows are several photos that chronicle some of my fall wanderings in the greater Yellowstone area, both in terms of wildlife and geology.

Some of my favorite sightings in YNP are bison at any time of the year. But the autumn snows bring on the bison’s technique of using its head to clear snow away from any vegetative food source. The result of their snow-clearing activity is a snow-masked face.

Snow-caked face of a bison in YNP portends the winter food retrieval.

Snow-masked bison near Soda Butte Creek, YNP.

And where the snow hasn’t stacked up much, the YNP bison calmly graze and occasionally congregate on a ridge line to watch what remains of the YNP visitor traffic.

YNP bison contemplating passing vehicles.

Geological features in YNP take on new dimensions with the golden low and slanting light of autumn. I’ve spent much time re-photographing geologic features at all scales that seem to glow in this season’s light.

Tertiary sediments and Quaternary sediments/basalts of “The Narrows” cliff face adjacent to the Yellowstone River, northern YNP. Columnar basalt capped by auto-brecciated basalt makes a morel-like image for these geological units.

An early morning at -7 F on the Lamar River with steam fog resulting from the fall’s chilled air moving over water still warmed from summer.

A rodent trackway disappears into microterracettes of Palette Springs, Mammoth Hot Springs, YNP.

Microbial growth near the proximal part of Mound Springs, Mammoth Hot Springs, YNP.

The proximal end of Mound Springs abounds in various colored microbial life. It’s hard to stop photographing these features because they are so intriguing!

The lipped margin of Mound Spring’s pond facies, Mammoth Hot Springs, YNP.

The fall staging areas of sandhill cranes in southwestern Montana are mesmerizing. Staging areas are those locations where cranes annually congregate during late September into October, spend several days foraging through fields for food, and eventually continue on their migration southward from Montana to Colorado and the southwestern U.S.. The staging area that I usually go to is near Dillon, Montana, where hundreds of cranes can be viewed.

Sandhill crane interaction during their fall staging near Dillon, Montana.

Sandhill cranes doing a dance routine in the Dillon, Montana staging area.

As I said initially, it’s hard to surpass a Montana/YNP autumn!

As Wildlands Fires Ravage Western U.S. – Is This The New Normal?

Over 100 wildlands fires are burning in the U.S., with most of them being in the western U.S. The California fires are exceedingly destructive, with Cal Fire officials calling this the new normal for the now extended and catastrophic fire seasons that we are experiencing. In the midst of all this, there’s a particularly good Ted talk on megafires done by Paul Hessburg at the TEDx event in Bend, Oregon, 2017. The video is well worth viewing:

Greater Yellowstone Area Eocene to Recent Hydrothermal Springs

The Gravelly Range spring deposits depicted in this photo are late Eocene (probably 34-36 million years in age).

Geologic field work is always fun, but especially so when it turns up something unexpected. Working on Eocene to Recent geology and vertebrate paleontology in the Gravelly Range, southwestern Montana promised to be enthralling because the volcanics, sedimentary units, and vertebrate fossils are at elevations of about 9,000 feet. But to come across extensive, unmapped calcareous spring deposits of probable Eocene age is topping off research efforts.

At this point, I’ll just say that our field team is still at work on the Tertiary spring deposits. We’ve found numerous leaf impressions including those of ginkgo, palm, metasequoia, Fagopsis (extinct member of Beech family), and alder – just to name a few. We’ve shown the plant assemblage collected to date to several paleobotanists, and, at least for age, their take is that the assemblage is probably latest Eocene in age, and bears many similarities to Florissant, Colorado fossil plant assemblages.

Palm frond impression from Gravelly Range spring deposit.

Ginkgo leaf impression from a Gravelly Range spring deposit.

Alnus cone from a Gravelly Range Spring deposit.

The spring deposits in the Gravelly Range are extensive, covering an area roughly 2 miles in length with deposits up to 120 feet in thickness. The springs are best characterized as travertine, although the spring systems’ edges contain clastic fluvial units and both the springs’ edges and pools have features such as plant impressions, root systems, and small travertine balls.

Gravelly Range Eocene spring deposit. Field backpacks in lower left corner for scale.

Because the Gravelly Range is so close to Yellowstone National Park, it is extremely interesting to compare its Eocene spring deposits to hydrothermal units at both the currently active Mammoth Hot Springs (which probably began its activity about 7,700 years ago), and to the fossil travertine found just north of Gardiner, Montana, that formed about 19.500 to 38,700 years ago (Fouke and Murphy, 2016: The Art of Yellowstone Science: Mammoth Hot Springs as a Window on the Universe).

The Gardiner travertine is fairly well exposed because it has been extensively quarried for several decades. Of interest for comparison are numerous plant impressions that occur within microterracettes. Fouke and Murphy (2016) suggest that these may be impressions of sage brush. A photo of the quarried wall with the plant impressions is shown below.

Plant impressions in Gardiner travertine. These impressions may be from sage brush. The travertine in this quarry face is estimated at about 30,000 years in age.

Other features in the Gardiner travertine, now partly covered by graffiti, include a quarry wall that shows terracettes and microterracettes that are outlined by darker lines within the travertine. These features are probably indicative of a proximal slope facies.

Gardiner travertine with its slope facies depicted well in smooth quarry face. The dark, irregular lines delineate terracettes and microterracettes.

Jumping forward in time to the extensive spring deposits of Mammoth Hot Springs (just within the northeast park boundary of Yellowstone National Park), is mind boggling. As in any comparison with rocks as old as Eocene to active deposition, one realizes how much detail is lost over time. But it is still worthwhile to try to compare spring features, so I’ll show a few photos of the Mammoth Hot Springs that may match up with various features of the fossil springs.

Branch and plant fragments in the process of becoming calcified at Mammoth Hot Springs – main terrace.

Calcified plant debris – Mammoth main terrace.

Terracettes – Mammoth main terrace, proximal slope facies.

Trees engulfed by prograding spring activity – Mammoth main terrace.

Travertine balls in small pond – Mammoth main terrace.

Suffice it to say, that the upcoming field season should be a good one, with more work to be done on the Gravelly Range spring deposits. And – it’s always fun to get a trip in to Yellowstone!

Tertiary geology and paleontology of the central Gravelly Range – a project update

The 2017 field crew working at Lazyman Hill. The strata are late Eocene (probably 34-36 million years in age) tufa deposits.

It’s time for our yearly update talk on field work and data compilation for the Tertiary geology and paleontology of the central Gravelly Range project in southwestern Montana. The Madison Ranger District in Ennis, Montana (5 Forest Service Road) will be hosting my talk on Monday, April 2nd at 10am in the Madison Ranger District conference room. We have a project permit from the US Forest Service because our project area lies within the Madison Ranger District – and the USFS District people have been really helpful with our project logistics. Thus, this is the perfect way to let them know what we did this past field season and how the whole project is coming together. The Madison District just sent their public announcement for the talk:

Dr. Hanneman and Dr. Don Lofgren, PhD (Director, Raymond M. Alf Museum of Paleontology, Claremont, CA 91711) and their team have been executing a multiyear study in the Gravelly Range near Black Butte resulting in many interesting paleontological findings right here in our own back yard.  Please join Dr. Hanneman and the Madison Ranger District for an update on this project and what they hope to unearth this year!

It’s a very intriguing project on high-elevation, mainly Eocene-Oligocene Tertiary geology and paleontology (mostly vertebrate and floral). So – anyone with an interest in this and who is in the geographic area, is welcome at the talk!

The Climate Change Factor in Extreme Weather Events

The 4 Mile Creek area near Boulder, Colorado, was devastated by an extreme rain/flood event in September 2013.

An op-ed in today’s New York Times, How We Know It Was Climate Change,  is well worth reading. The author of the op-ed, N.S. Diffenbaugh, lays out the rationale for a link between climate change and extreme weather events. Diffenbaugh’s op-ed is based on a journal article written by himself and others that was published in the Proceedings of the National Academy of Sciences (PNAS – 3/17), Quantifying the influence of global warming on unprecedented extreme climate events.

Both the op-ed and the PNAS article are essential reads for the new year.

Cuban Geology – An Updated Resource List

Vinales Valley in Cuba was designated a UNESCO World Heritage Site in 1999.

Within the last few weeks I’ve had several requests for available resources on Cuban geology. The requests, of course, have come from individuals outside of the U.S.A. Guess that they sense opportunities for working with and understanding Cuba’s geology that we are backing away from. In any case, I’ve sent the requests on to Manuel Iturralde-Vinet, the person who has worked and published an immense amount of information regarding Cuba’s geology. Manuel has now sent me back an updated list of resources and said:

You can advertise to all your friends and colleagues that a large
percentage of the geology, geography, paleontology, geophysics and
mining papers are free to be visited at
http://www.redciencia.cu/geobiblio/inicioEN.html

Other resources that are available include: http://www.redciencia.cu/cdorigen/arca/iturra.html

Field Trip Guides to Cuban Geology: 2001, IV Cuban Geological and Mining Congress: K-T Boundary of Western Cuba

— 2001, IV Cuban Geological and Mining Congress: Former Caribbean Plate Boundary, Camaguey, central Cuba

Compendio de Geología de Cuba y del Caribe. Segunda Edición 2012:
http://www.editorialcitmatel.cu/producto.php?producto=128

Videos de Viajes: http://www.youtube.com/user/IturraldeVinent2011#grid/user/A43949937C36E7BC

Videos de Geología y Naturaleza: http://www.youtube.com/user/IturraldeVinent2011#grid/user/DE8FDB5CE5960C19

Geological Society of America: The Geological Society’s (GSA) annual meeting in Denver, 2016, hosted a special session on the Geologic Evolution of Cuba. A link to session abstracts is: GSA Geologic Evolution of Cuba. The GSA Today October 2016 issue also highlighted Cuba Geology with the article “The geology of Cuba: A brief overview and synthesisauthored by Manuel Iturralde-Vinet and others.

Earth Magazine: Travels in Geology: Journeying Through Cuba’s Geology and Culture.