Exploring Italy

Charlie and I were super excited to take the train south from Potenza on Tuesday and enter “The Zone”!  This place has a magical draw for both of us: for the ancient history (Greeks and Romans), the more ancient history (geology, active tectonics, sedimentology, rapid uplift and mountain building), culture, food, people, and the Messina Strait itself.  Two days ago we worked here in Calabria, not far from our apartment in Reggio Calabria.  Then yesterday we went to Sicily.  The photo below was taken from near the NE end of the Peloritani Mountains in Sicily, looking ~ENE through the narrow constriction of the active conjugate relay zone where extensional strain is transferred from NW-dipping normal faults in Calabria to SE-dipping normal faults in Sicily.  Sorry for TMI!

To get there we took a ferry across the narrow part of the strait from Villa San Giovani to the historic city of Messina, which was destroyed by a M7.1 earthquake in 1908. The fault structure responsible for this earthquake, the source of tsunamis that inundated coastal cities during the event, and the geometry of faults that drive active seismicity in the region are all the subject of active research and debate.  Here is the waterfront of Messina as seen from our ferry on our approach to the port, with the low young mountain range behind it.

We undertook this first round of fieldwork with our friend and colleague Domenico Chiarella, who is originally from Calabria and is now a professor at Royal Holloway University in London. Domenico is a great geologist and stratigrapher who has studied the sedimentology and evolution of the Messina Strait region for many years, and he knows the area very well. Below is a shot of Charlie and Domenico as we headed out yesterday:

This was out first trip to Sicily and we were not disappointed! The goal of our mission on this day was to find, describe, and collect a tuff interbedded in a claystone deposit called Argille di Spadafora which, based on microfossils and biostratigraphy, formed in a deep marine basin sometime between 500,000 and 1 million years ago. Since then this marine clay unit has been uplifted to elevations up to 500 meters above sea level in northeastern Sicily. The photo below shows our approach to the collecting site.  We did have permission from the land owner to access this site, and the cows also seemed to approve.

We found the tuff!  Below you can see Domenico moving in for a close look, and yes it’s a tuff!

Below is the obligatory close-up view.  This is an inversely graded tuff with horizontally stratified well sorted ash in the lower part that coarsens up into lapilli tuff with granule-size pumice fragments and out-sized pumice pieces up to 4 cm long.  We collected this tuff, and hope to find sanidine grains that can be dated with argon isotopes at a lab in Pisa.  There is a lot more to say about this, maybe in a future post.

The ferry back to Calabria at the end of the day was breath-taking. In the view below there are at least 4 prominent terrace levels that represent uplifted remnants of an ancient marine shelf.  Can you spot them?

Today we went back to work on the Calabrian side.  Our first stop was a photo op looking southwest toward the looming majestic active volcano at Mount Etna. More breath-taking moments.

Below is a shot of the boys, feeling good after collecting our second sample!  This one was a detrital sandstone sample, which means it is a mix of grains with a range of different compositions.  If we are lucky enough to find sanidine grains, they are likely to have a wide range of ages which makes dating the age of deposition more difficult but not impossible.

We finished up with some more field work, then Domenico dropped us off at our apartment and drove to the airport to take a plane back to London. We found a little pizzeria and had a slice of pizza and aranciata (fizzy orange juice), then took a stroll along the gorgeous waterfront of Reggio Calabria. Domenico told us that a famous 20th century Italian poet  declared this to be “the most beautiful kilometer in Italy” (even though, or maybe because, he was from northern Italy). I would have to agree.

Charlie and I now have a few days “off” to explore the city and maybe take a day trip to – who knows where – there are lots of options.  Then back to field work next week.  The adventure continues!

We have enjoyed a wonderful visit in the historic city of Potenza!  It rained the first couple of days, which we didn’t mind because we are staying in a cozy little apartment across a small stone piazza from the Chiesa (church) of San Michele de Arcangelo.  We lived near here for 3 months in 2022, and it feels like home.  Below is Charlie outside our apartment:

I wandered across the piazza into the Chiesa di San Michele, and was treated to traditional live organ music and classic religious art:

Today the sun came out and it was a gorgeous day. In the afternoon we went for a long wandering walk around the eastern part of the city, visiting places that were both known and new to us. Below is a picture of Charlie looking stylish on Via Pretoria, the pedestrian walking street in the centro storico (no cars).  We enjoy strolling along with the local people who flock here in lively crowds, especially in the evening, to “swim laps”.

Below is one of the historic gates of the city: it’s very old, centuries!  (we don’t know the original date).  This gate was nearly destroyed in the 1980 M-6.9 Irpinia earthquake, which devastated much of the Basilicata region and damaged many historic buildings in Potenza. The gate was subsequently rebuilt and restored, as seen below:

This is a view overlooking the Universita degli Studi della Basilicata (“Unibas”), the academic home of our friend and colleague Sergio Longhitano.  Here we are looking about south, and the east end of the old city is on the ridge at the right.

Outside the Geosciences department at Unibas, there is a new display of geo-educational poster boards.  This one caught my eye because it highlights extension and normal faults superimposed on the Apennine thrust belt, and an outcrop!

Here we see a historic stone tower that was built circa 700 to 900 A.D. (accounts vary). The city of Potenza is in the process of restoring the tower within a beautiful plaza, so we could not go there today, but maybe in a future visit:

Many of the cars here are very small, and electric! The traditional-style cobble paving stones and old stone buildings provide a fun backdrop to this modern compact form of transportation. There are also many public-transit options (bus and train).

Finally, we introduce you to the revered and beloved patron saint of Potenza, San Gerardo (below). According to Wikipedia, Gerardo was the bishop of Potenza in the early 12th century and led the church for 8 years. One year after his death in 1120, Pope Callistus II proclaimed him to be a saint, and immediately the people of Potenza began to venerate him. There is a colorful legend that Gerardo performed a miracle by driving off an army of invading Turks, and the event is celebrated to this day in a rowdy long weekend of parades, music, and performances during which the city becomes filled to bursting with people from all over the region. We were lucky to be here for this event in 2022, it was amazing.  If interested, you can scroll down to my post from June 4, 2022, to see some images from the Festival of San Gerardo that year.

Tomorrow we will leave Potenza and travel by train to Reggio Calabria, where we will move into our apartment and get ready to start field work with Sergio and Domenico.  To be continued …

Charlie and I are excited to be back in Italy!  This post will be light on text and heavy on photos. Our trip to Naples was long but smooth. We stayed in a cool little BnB in the heart of the Centro Storico and immediately dove into the street scene on Day 1, shown below.

We hiked up a steep hill to the Monastery of San Martino and got some great views of the city, with the volcano of Mount Vesuvius looming over Naples in the background:

We then met a great geologist and professor at the University of Naples Federico II, Stefano Vitale, and his PhD student Mubashir Mehmood (seen with Charlie below), who gave us an excellent walking tour of many churches and unique sights in Naples.

The next day Mubashir took us to see active fumaroles of the restless hydrothermal system of the Campi Flegrei within a giant caldera system, west of Naples along the coast (see below), which has gotten a lot of attention recently due to increased earthquakes and magmatic activity … waiting for the next super eruption!

We spent the rest of that day touring a few Roman ruins, including an ancient hot springs resort and a fascinating museum in a castle at Bacoli that provided fantastic sunset views of Vesuvius.

We are now in Potenza, which was our home for 3 months in 2022.  My next post will share some photos from here.

Our paper on the Messina Strait is now published in the journal Basin Research.  It’s exciting to see the paper published after an efficient review process and with initial support from the international geoscience community.  It has been a pleasure collaborating with Sergio Longhitano and Domenico Chiarella on this project.  We look forward to future work in the Messina Strait region!

There are three ways to access this paper:

1. A read-only pdf of the article can be viewed online here.
2. You can download a preprint version at EarthArXiv here.
3. Download the paper from Sergio’s website here.

The citation is: Dorsey, R.J., Longhitano, S.G., & Chiarella, D. (2024). Structure and morphology of an active conjugate relay zone, Messina Strait, southern Italy. Basin Research. vol. 36 (1), 21 pp.  https://doi.org/10.1111/bre.12818.

Hypothesis for a Migrating Conjugate Relay Zone in the Messina Strait, Southern Italy

(abstract presented at the Tidalites Conference, early May, 2022: https://www.tidalites2022.it/)

¹Dorsey, R.J.,²Longhitano, S.G., ³Chiarella, D.

(1) Department of Earth Sciences, University of Oregon, Eugene, OR (USA); (2) Department of Sciences, University of Basilicata, Potenza (Italy); (3) Department of Earth Sciences, Royal Holloway University of London (UK)

The Messina Strait (MS) is a modern, 3-km-wide tide-dominated passageway that separates the Italian peninsula from Sicily in the central Mediterranean Basin (Fig. 1A). The MS sits in a tectonically active region where seismogenic normal faults, sedimentary facies of Plio-Pleistocene deposits, and age of uplifted marine terraces provide a record of rapid extension and vertical crustal motions driven by southeastward rollback of the Calabrian subduction zone. Southern Calabria and northeast Sicily occupy a microplate bounded by active NW-striking strike-slip faults that mark the surface expression of growing tears in the subducting Ionian oceanic slab (Fig. 1A). Within this setting, large water masses of the Ionian and Tyrrhenian seas are compressed daily through the MS to produce horizontally-amplified tidal currents and a resulting wide range of erosional and depositional tidal processes (Longhitano, 2018). The bathymetric and geomorphic features of the MS are known to be tectonically controlled, yet their governing fault geometries and fault-kinematic processes remain poorly understood.

A review of published studies in southern Italy reveals a distinctive fault pattern that is best described as a conjugate relay zone (c.f. Childs et al., 2019), where displacement on opposed-dipping normal faults is transferred along-strike through a zone of overlapping extensional conjugate faults. The MS persists today within such a zone of overlap where strain is transferred from NW-dipping normal faults in southern Calabria to the SE-dipping Messina-Taormina normal fault offshore of northeast Sicily (Fig. 1B). The epicenter of the 1908 M 7.1 Messina earthquake is located roughly in the center of this relay zone. The narrow hook-shaped constriction at the northern exit of the MS is defined by pronounced plan-view curvature in facing conjugate normal faults that may reflect large strain gradients and local rotations near active fault tips in the locus of modern fault interactions, accommodated by slip on the offshore oblique-dextral Capo Peloro fault. Pleistocene marine terraces preserved at elevations up to 1.3 km asl in southern Calabria (Fig. 1B; Roda-Boluda and Whittaker, 2017; Antonioli et al., 2021, Meschis et al., 2022) record northwestward migration of normal faults in the past ~1 Myr. We speculate that a set of en-echelon normal faults at the eastern margin of the Messina Strait (west flank of Aspromonte Mts.) formed by northward migration of normal faults in response to NE-ward propagation of the Messina-Taormina fault (Fig. 1B). This hypothesis makes a number of testable predictions that could be evaluated in future work.  For example, if fault interactions in the relay zone control preferential directions of incoming and outgoing tidal flows, they may thus influence the asymmetric partitioning of modern depositional environments and help to explain observed differences in sedimentary deposits north and south of the narrow MS exit.

We recovered from the covid, thankfully. On our last day in Potenza, Sergio and his students hosted a party for me and Charlie where we received a couple of small gifts including a full size color geologic map of Italy! In the evening we strolled around the streets of Potenza with Sergio and his wonderful wife Marta and their 3 daughters, Gaia, Aurora and Alice.  We had a light dinner with snacks and beer where Alice (5 yrs old?) performed an elaborate chemistry experiment that involved moving water between many cups on the table, and we ended with a selfie in the Piazza Mario Pagano right outside our apartment. Today we moved out and our host gave us a ride to the Potenza bus station, and we are now in Naples ready to fly back to the U.S. tomorrow. We already miss Potenza and the many wonderful people who we met. I am especially grateful to Sergio and his family and colleagues who made it such a special visit for us. Sergio and I will continue collaborating on stratigraphy and tectonics of southern Italy, and we look forward to returning for more adventures!

Charlie and I thought we might skate through the pandemic without getting infected, but no such luck.  We got sick and tested positive a week ago in Bari, on the coast of the Adriatic Sea, where we attended the 2-day GeoSed conference. Whoops! We stayed an extra 2 nights at a hotel in Bari, and then got a very expensive taxi ride back to Potenza (big tip to the driver who agreed to take us). We have been isolating in our apartment since then, feeling pretty sick and out of it.  Our friends Sergio and Gianpaolo have been heroes, delivering food and supplies and even a direct phone consultation with a doctor early-on. Today I tested negative though still feel like I have a head cold, and Charlie is still testing positive but feeling better every day. We did find out that all the published guidelines will allow us to travel to Naples a week from today (Day 14) and fly back to the U.S. the next day July 1 … thus marking an unexpected twist to our last 2 weeks in Italy.  PS – COVID19 really sucks, best to avoid catching it if possible!

Above: COVID-19 survival kit, Potenza Italy.

On June 13 we attended a one-day field trip with a group of Italian sedimentologists going by the name “GeoSed”, to view Cretaceous and Miocene sedimentary rocks exposed near the crest of the southern Apennine orogenic belt. It was a gorgeous sunny day, I learned a lot and the company was great! Charlie and Sergio struck some memorable poses (see below).  We saw a thick section of Cretaceous marine deposits that were overturned by strong back-thrusting and folding near the crest of the Apennine orogen, and wound up with overturned bedding dips of 30-40° to the NE. We ended the day on a walk through the quaint town of Pietrapertosa, just another gorgeous Italian hilltop ancient stone city.  Photos below.

Above: Charlie and Sergio enjoying the day.

Above: field trip leaders doing what field trip leaders do.

Hey sedimentologists, these turbidites are up-side-down!

Above: Miocene Gorgoglioni Flysch, amalgamated sandy channel-fill turbidite complex.

The boys looking good!

Above: Nice exposures in the hill top town of Pietrapertosa.

Above: Roadside cafe built into channel sandstone with rip-up clasts!

We are finding that the Italian people really love their history and holidays. Recently Potenza hosted a 3-day festival in honor of San Gerardo, the revered patron saint of Potenza. This festival celebrates an event in the year 1111 when San Gerardo is said to have used a magical force of light to repel an attack on Potenza by intruders commonly described as “Turks”. Some myths say that the attackers were actually Saracens from the Syrian or Arabian desert, and other accounts assert that the fighting took place in Germany and the story was translated to southern Italy for religious or political reasons. Regardless of such details, the people of Potenza go all-in on this celebration which included days of singing and partying in the streets, and culminated with the very popular Parade of the Turks. Photos below provide a sample of the energy and color of this event.

Last weekend we took the train to the city of Salerno where we stayed in the Palazzo Conforti, an old palace built at the end of the 18th century. Our room was grand, with a view of the harbor and a classic colorful painting that covered the ceiling! We visited an old church where a Catholic service featured choral singing and gorgeous organ music. Next day we took the ferry to Positano on the Amalfi Coast, which is really just a mind blower. Small towns and villages climb up sheer cliffs of limestone that are incised by vertical deep gorges, looks like it must be an actively uplifting peninsula. And I swam in the Tyrrhenian Sea! On Day 3 we visited the ancient Greek city of Poseidonia (Paestum) which flourished between ~ 550 to 450 BC, with large temples to Athena, Neptune and Hera. I learned that in the 5th century BC, the Greeks employed the local people, known as Italics or Lucanians, as mercenaries to fight wars for them. However, in the 4th century BC the Italic people took over the city and they became the ruling class. Later the Romans moved in, and the city prospered during the early years of the Roman Empire. Finally, silting up of the mouth of the Silarus River created a malarial swamp and Paestum was deserted after being sacked by Muslim raiders in AD 871. A few photos below.