Have you ever wondered how many volcanoes there are in your country, or how many earthquakes have occurred in the past 24 hours? Have you ever wanted to travel and see a volcano, but you don’t know where to start? www.volcanodiscovery.com is a great website if you want to know anything and everything about the geography of volcanoes. When you first go to the website, there are simple categories on what you are specifically looking for. For example, if you click on the first box that says “Volcanoes of the world,” there is information and news about active volcanoes from all around the world. You could click on a country such as Japan, for example, to find out how many volcanoes are on that island, and find out facts about them. You could also click on the category called “Volcano photos,” to see magnificent photographs of different types of active volcanoes. There is also a “photo of the day” category, in which you could check back every day to see a new photo. Another interesting category is the “Volcano travel,” in which you could find out where you can visit to see volcanoes. There are even specific dates and tours that you could sign up for. Another category that is convenient is the “Latest earthquakes” category. Here, you can find out the latest earthquakes from around the world and their magnitudes.

Researchers at the University of Texas — Austin Jackson School of the Geosciences have recently conducted a study, featured in the April 22, 2016, edition of Science, hypothesizing that volcanic activity associated with plate tectonic movement is a contributing factor to the global climatic shift to higher temperatures. This study analyzes shifts in the Earth’s baseline climate throughout Earth’s 4.6 billion year existence; the study focuses on long-term shift, not short-term/human-induced climate change. The researchers, using a geomorphological lens to examine climate change shifts concluded, ” periods when volcanoes along continental arcs were more active coincided with warmer, or greenhouse, conditions over the past 720 million years. Conversely,  periods when continental arc volcanos were less active coincided with colder, or icehouse, conditions” (University of Texas at Austin). The research team argues that when crustal collisions occur throughout Earth’s history, the effects of plates colliding can increase Earth’s temperatures, especially collisions that result in volcano formation.

Continental arc systems, the researchers argue, act as reservoir for carbon, until volcanic eruption releases carbon into the atmosphere. Continental arc systems are created by the collision of two tectonic plates and the oceanic plate is subverted by the continental plate, forming a subduction zone where magma mixes with trapped carbon to release carbon dioxide when volcanoes erupt.  The amount of carbon dioxide released and held in the atmosphere “influences Earth’s climate.” The research team compiled over 200 published studies, in addition to their own data, to study the past 720 million years of Earth’s geology. The team constructed a global database cataloging the most recent 720 million years of volcanic activity at the margins of the continental plates. The study also examined other greenhouse gases and sediment basins of eroded volcanic structures in order to improve their model.

In concluding statements, team contributor Brian Horton stated, “the cooler icehouse periods tended to correlate with the assembly of the Earth’s supercontinents, which was a time of diminished continental volcanism. The warmer greenhouse periods correlated with continental breakup, a time of enhanced continental volcanism.” This study is important to physical geography because it is representative of the interconnectedness and interdependence Earth’s systems have with one another. The lithosphere and the atmosphere are not independent of each other, but exogenic processes that occur in one sphere or system of the Earth affects the other system.

Source: https://www.sciencedaily.com/releases/2016/04/160421150056.htm

University of Wyoming Researcher, Kevin Chamberlain, has helped disprove a previously wide-held theory of two Precambrian super continents (called Nuna-Columbia and Rodinia) using a technique called “diking,” which examines specific types of layers in rocks called dikes. Chamberlain examined “mafic” dikes in layers of rock, which are dark bands of mineral or rock containing magnesium and iron that form between existing, older rocks. Chamberlain found similar dike swarms (cluster of dikes within the continental crust) in the Southern regions of Siberia and mountain ranges of Wyoming, as well as similar ages of cratons and dike swarms in the two regions. This helped determine when and where the cratons split apart and caused continent reformation, which proved that the Southern region of Siberia and the core of North America where Wyoming’s mountain ranges fall were connected at one point. The findings helped Chamberlain conclude that these regions were connected for about 1.2 billion years, anywhere from 1.9 to 700 million years ago, as one of four or five hypothesized super continent cycles.

The discovery also brought good news to the futures of mining companies. The uncovering of similar dike swarms and craton ages in the two geographic regions reveal that large metal deposits are likely to exist under the younger layers of rock.

Find the article at : https://www.sciencedaily.com/releases/2016/04/160412091348.htm

Researchers from Penn. State University have discovered a new geological source for strong earthquakes known as “diking”. Diking can be found all over the globe, but it is a phenomenon that is primarily focused along divergent plate boundaries (e.g. East Africa’s Great Rift Valley). This phenomenon occurs when magma rises from diverging plate boundaries in order to fill empty spaces. The magma then proceeds to cool and form vertical intrusions known as dikes. Although diking is a known phenomenon, “it has not been observed by geophysical techniques…”.

Penn State researchers led a study that explored the connection between two natural disasters that occurred in the Democratic Republic of Congo in 2002. Chrsitelle Wauthier, the assistant professor of Geosciences at Penn. State, led the study in East Africa. The research team studied the eruption of the Nyiragongo Volcano on January 17th, killing over 100 and leaving around 100,000 homeless, and 6.2 magnitude earthquake which hit the town of Kalehe 8 months later.

Although the research team understood that the entrance of magma to the Earth’s crust creates stress and generates seismicity, they were still perplexed by the magnitude of the earthquake that hit Kalehe after the eruption of Nyiragongo. Earthquakes created by the entrance of magma to the Earth’s crust are usually small in magnitude, but the earthquake that hit Kalehe was quite high.

The research team therefore concluded that the rising magma that created dikes were putting pressure on adjacent rocks in the Earth’s crust. The increased pressure of these adjacent rocks accumulated stress upon rocks found on a fault in Kalehe. Therefore, the research team discovered  that dikes have the potential to trigger much larger earthquakes than previously believed.

Source: https://www.sciencedaily.com/releases/2016/02/160208124248.htm