The Weekly Update (29/04/16)

Welcome to The Weekly Update! This week’s roundup follows last week’s fairly quiet period with another fairly quiet period with only 12 or so volcanoes producing enough of an ash cloud to be considered worthy of a VAAC report.  Due to work commitments this week, the report runs from the 21st of April to the…

Biology, Sheep, and Human Survival

This is a reposted article from November 21, 2011 As a biologist I feel I really must reply to the Blog on behalf of the sheep. I don’t know how many biologists read these Volcanic blogs and I wonder if geologists and physicists have a true concept of the science of Biology. I decided to…

An Overview of Eruption Types

From time to time when we discuss our beloved volcanoes, we get a mild-mannered enquiry – ”Excuse me, but what’s effusive? And that cryptodome you are all speaking of, what is that?” I thought I’d take the time to jot down a few notes trying to explain what is meant by the various types and…

The Weekly Update #11 (22/04/16)

Welcome to a fairly quiet Weekly Update. Following the excitement of Sakurajima, Popocatepetl and Zhupanovski over the past couple of weeks, I guess the Volcano Gods are taking a break. We start as ever with the quiet zones, London, Toulouse,Anchorage, Montreal and Wellington all have no reports in their respective VAAC areas of operation.   Washington VAAC Colima A quiet…

The Weekly Update #10 (15/4/16)

Welcome to a double edition of the Weekly Update. Following last weeks “incident”, where my cat Jeff somehow contrived to destroy my modem, this week we are covering two weeks worth of VAAC reports, so without too much preamble we will plow ahead. A slight change to how I have chosen to display the images this…

Jan Mayen – The Fiery end of Civilization

The Norwegian island of Jan Mayen is situated north of Iceland. It might be the only place on earth where no one yet has bothered to find anything valuable. Except for a short stint in the early twentieth century when Norwegian trappers hunted polar bears and blue fox. Jan Mayen services as a combined polar…

Reinterpreting Grimsvötn

In the previous part we learned that Grimsvötn indeed is able to produce large scale eruptions as we looked closer into the Saksunarvatn tephras. The first part can be found by following the link below. http://www.volcanocafe.org/grimsvotn-the-saksunarvatn-tephras/ This time we will look into what this new information might mean for the future eruptions of Grimsvötn. But…

All Calderas are not Calderas

Sometimes our readers send in questions to us that literally sends the writers into a frenzy of volcanic exploration. This week’s question was about if the area between Fort Rock and Chemult in Oregon is indeed a large caldera. The area is situated south of the eastward Cascade volcanic range south of Newberry (Paulina Peak),…

The Aniakchak Earthquakes

Few of our readers have missed the anomalous M6.2 earthquake that occured 20 km WNW of the Aniakchak Caldera. In this article we will go through the details of the earthquake and the possible effects of the main-shock and the series of after-shocks. According to the Alaska Earthquake Center the waveform of the initial 6.2…