A team of geologists from the Museum and Imperial College are in Mexico carrying out  fieldwork at two of the most active volcanoes in the world: Popocatépetl (Popo) and Colima. Catch up with their adventures in this series of blogposts.

Popo times are over (never mind the blog title), but for Chiara and me the journey continues: Colima volcano, here we come! We have planned three days in Colima, and since winter in Mexico is generally a time free of clouds and rain, we are fairly confident that we will get some great shots of this impressive volcano. But alas!, as we arrive at the tiny Colima airport, we find that the view of Colima volcano is somehow underwhelming:

Harder than spotting lava at Popocatépetl's flanks: Whoever finds Colima volcano in this photograph is a true eagle-eyes and deserves an honorary display in the Museum's bird galleries.

The weather in Colima remains tropically hot, damp and cloudy for the next one and a half days. Chiara makes the best out of the bad conditions by giving a spontaneous talk about her work at the University of Colima, while I use the time to give you some background information about Colima volcano:

Fuego de Colima, as the volcano is called, has been very active in historical times. There were large eruptions about every 100 years in the past, which directly leads us to the alarming part of the story: the last major eruption took place in 1913! And the volcano has certainly woken up in the past few years, with volcanic domes - very viscous lava forming a plug in the crater - frequently being built and subsequently destroyed. (By the way, this is exactly the same type of activity as we see at Popocatépetl, even though the volcanoes are very different in other aspects.)

Fuego de Colima, and its snowcapped older sister, Nevado de Colima, form an impressive mountain mass towering above the State of Colima. Fuego de Colima has been very active in the past few months.

Especially since last summer, Colima has produced several small- to medium-sized eruptions every day; one of the largest since 2005 happened while we were peacefully collecting pumice at Popo:

It seems that Fuego de Colima is preparing for something bigger in the foreseeable future, and authorities are on alert in order to protect the ~300,000 people living in the vicinity of the volcano.

After intense rainfall during the second day, the weather clears in the evening, raising our hopes to finally see some action. And as it turns out, we get even more action than we were daring to dream of: we get offered a flight in a small airplane around the volcano on the third day of our stay. Obviously, this is an offer we can't refuse, especially after we are being reassured that the pilot is very experienced and knows how close he can get to the crater without getting into eruptive trouble. So off we go! Take a look at the stunning pictures we were able to take:

Colima volcano, airplane view: gases are constantly emitted from the crater region. The surface of this area is several hundred degrees celsius.

Even though there is some zoom involved in the picture, we are disquietingly close to the place where the explosions happen. The channel in the foreground of the picture is in fact a lava flow descending Colima's SW flank.

A steamy view to the North, with the newest lava flow going down the left side of the picture. The very top of the volcano is a flat or even slightly concave surface (just as a proper crater should be)…

…In December 2013, the summit looked very different. Here, we can see a fully intact, hemispherical dome. The explosions that have taken place since then have literally blasted off the cap of the dome.

After the flight: Chiara is happy about what she has seen, as well as about being safely back on solid ground.

As soon as we are back at the airport, the volcano starts an impressive performance of steam and ash emissions. We congratulate ourselves that we are not in an airplane above the top right now and take more pictures!

This eruption column is about 4 km high and contains very little ash, as can be gathered from the bright colour. However, if you look closely, you can see some ash falling out of the cloud towards the ground.

Night falls, and Fuego de Colima continues its show.

We could show you plenty more pictures of Colima erupting, since it continued similarly throughout the rest of our stay (and is still ongoing!) and we were quite trigger-happy. But this blog entry is already quite long, so if you want to see more of Colima volcano, we would like to refer you to the freely accessible webcam that delivers live, high-quality pictures right to your computer screen. As I said, there are several eruptions like the ones shown above every day, so if you spend some time with it, chances are that you will be live witness of a proper volcanic eruption!

Sadly, our time at Colima is already over now, and also our field campaign draws to a close. Stop by here shortly for final, picturesque remarks about our work in Mexico.

A team of geologists from the Museum and Imperial College are in Mexico carrying out  fieldwork at two of the most active volcanoes in the world: Popocatépetl (Popo) and Colima. Catch up with their adventures in this series of blogposts.

After our dirty but successful pumice-rich first week at Popocatépetl, we were all happy to get that dust off our shoulders and start chasing the various lava flows that make up most of the volcano edifice. Now, if the whole volcano is built by lava flows, it should be really easy to find these rocks, shouldn’t it? The short answer is: no. The longer, picturesque answer will take you into the wild, rough and bumpy world of Popo’s lower flanks, where a good rock is as hard to find as a sleeping baby lion in the vast African savannah. Join us on the magical ROCK SAFARI!

Early in the morning, when Popo is still entangled by the night’s misty claws, we make our way from the hotel in Amecameca towards the south-eastern flank of Popo, the land of the sneaky rocks.

Somewhere down there they are hiding: the Popocatepetl lava flows!

On the lookout for rocks: moving in this terrain makes you reconsider what you may call a ‘road’.

What makes it so difficult to find these lava flows is the fact that most of them are buried by a thick cover of the Popo pumices (not again!) and lahar deposits. So in many cases the only thing we can find on top of these dirty deposits are loose boulders of rock, which we can’t even be sure belong to the place we find them lying. A tedious job requiring lots of caution!

An easy catch: can you spot the rock?

Julie finds a rock that has tried to hide away from our hammers…

…we took care of it.

Such a seek-and-destroy campaign can easily take a couple of hours for one lava flow and is not necessarily successful. However difficult it may be, when you finally spot a nondescript, lichen-covered rock specimen, the adrenaline you feel while smashing it into pieces to see what species it is pays off generously.

Another boulder from a Popo lava flow successfully tracked down.

One factor that contributes to our (otherwise rather questionable) sense of adventurism during this rock safari is the daily recurrence of a group of local forest watchdogs roaming around the terrain. The first time they came, they only surrounded our car with a grim look on their faces, checking if we were hunters (if they could only know!).

The second time, they had machetes (they were cleaning the roads from vegetation) and we had to give them some money so they’d let us pass. The third time, it was already getting dark, and they had shotguns to guard a road against any people with mischief in mind. We certainly didn’t at this point. The good thing is that by now they know us and they greet us cheerfully every time we pass them.

Obviously, we weren’t keen on photographing the shotgun watchdogs, so instead we present evidence that some lava flows are not good at hiding away. This the Nealticán lava flow, which is the most recent of Popocatépetl’s lava flows (in geological terms, ‘recent’ means younger than 2,000 years). Because of its young age, it is not covered by a lot of deposits and is thus widely exposed. Unfortunately, this flow is the exception to the rule.

In this manner, we have chased down a couple of lava flows in the past few days. We are very happy with the outcome of our rock safari and can’t wait to introduce these samples to their new temporary habitat while they are shipped to the UK: cardboard boxes!

We are delighted to welcome you to our Popocatépetl blog, which for the next three weeks will be fed with facts, anecdotes, pictures and maybe even videos of our fieldwork at two of the currently most active volcanoes in the world: Popocatépetl (henceforth: Popo) and Colima (henceforth: Colima).

Our very first view on Popo, at dawn in Amecameca. Not yet convinced? Scroll down and prepare to be amazed!

But first things first: introductions. Our team includes Chiara, volcano-addicted petrologist at the Museum, Julie, passionate geochemist and lecturer at Imperial College, and me (Martin), their new PhD student. I'll be focusing all my energy on Popo in the coming years.

Together, we're setting out to shed light on what makes Popo erupt, a poorly understood yet very important issue, since there are more than 30 million people living around Popo – that’s about half the population of the UK! By analysing the rocks and crystals that Popo has erupted in the last 23,000 years, Chiara, Julie and myself are trying to find out more about how Popo works, which will hopefully help in forecasting future eruptions and keeping the people living there safe.

But to do all this, we first need rocks – a lot of rocks! And that’s exactly why we are in Mexico right now. Together with our local colleagues, Hugo and Guillem, we will spend our days at the volcano, looking for the freshest rocks around and putting them into plastic bags. As Popo is quite active in the moment, this is a quite exciting and dangerous task!

Popo is in a steamy mood these days.

But before we dive into excitement and danger with you, we want to give you an idea of our experiences during the last 48 hours. We started in London Heathrow (25.3m above sea level) on Sunday night, arrived in Mexico City twelve hours later, went straight up to Paso de Cortes (3,400m a.s.l) to get a close grasp of Popo, then had a decent rest in our hotel in Amecameca, just to get up again at 5.30 the next morning for a 10-hour day of die-hard pumice sampling at almost 4,000m a.s.l.

Now we are a bit tired – so we thought we would give you and us an easy start with some Popo pictures, taken all around the volcano. You will surely agree that Popo is in good shape, and a truly admirable volcano – ‘a proper strat’, as Julie put it musically.

Popo as seen from Paso de Cortes - preparing for the big bang?

Volcanic eruptions are not the only danger lurking at Popo's flanks. Luckily Julie knows no fear and chases away the feral cow.

After the cow-shock we seek comfort in some good old volcano stratigraphy!

If you want to know what Popo does next, how we deal with the thin air and the cows, and how fashionably we collect both hard and soft rocks, we urge you to come back here. Also, don’t be afraid to leave comments, questions, and general thoughts about volcanoes.