#seismology

#seismology

These Pictograms Are The First Written Accounts of Earthquake in the Americas in pre-Hispanic TimesMesoamerican civilizations have had their share of earthquakes in centuries past. After all, earthquakes happen frequently in their place. It is then no surprise that they have documented them in their pictograms, according to Gerardo Suárez, a researcher from the Universidad Nacional Autónoma de México. He, along with Virginia García-Acosta of the Centro de Investigaciones y Estudios Superiores en Antropología Social, have studied pictograms in the Codex Telleriano Remensis, a 16th century document created in Mexico. This Codex is said to report 12 earthquakes that occurred between 1460 and 1542.The pictograms offer little information on the location, size or damage caused by the earthquakes, the authors note in the journal Seismological Research Letters. But along with other historical accounts found in annals written after the Spanish conquest, they extend the region’s seismic history back into the 15th century.Aside from the frequency of earthquakes in the region, Suárez also states another reason these pictograms reported such events — Mesoamerican civilizations saw earthquakes as significant events in their cosmological view.Mesoamerican civilizations viewed the universe as cyclical, with successive eras or “suns” destroyed by floods, wind, fire and other phenomena before the appearance of a new sun. The current and fifth “sun, “according to this view, will be destroyed by earthquakes.The researchers state that this new finding "adds additional evidence that great earthquakes have occurred in this segment of the subduction zone before," and that the absence of these great earthquakes "should not be considered as though this region is aseismic." In other words, the said place still has seismic potential. The current inhabitants should remain vigilant.Learn more about this study over at the Seismological Society of America website.(All Images Credit: Gerardo Suárez and Virginia García-Acosta)#Pictogram #CodexTellerianoRemensis #Earthquakes #Seismology #SocialAnthropology #Mesoamerica #Mexico

The Earth's Core is Growing LopsidedRight beneath our feet, the Earth's core is doing something strange: it's growing more and more lopsided. But how?A new study by seismologists at the University of California, Berkeley, surmised that the core's mass accumulation has a lot to do with heat dissipation:The scientists say dissipating heat likely explains why the east Indonesia side is adding more iron crystals so much more rapidly. Those crystals form and are moved quickly into and toward the rest of the core, creating horizontally packed structures that explain the slower east-west seismic waves compared with the faster north-south seismic waves. Packed crystals are waiting in east-west queue lines that leave little room for seismic activity to pass through.The dissipating heat is likely due to Indonesia being covered by a huge mix of islands and expansive sea floor, which is a key place where molten materials shed heat from inside the Earth. On the western end, Brazil is part of the gigantic land mass of South America, leaving little space for the rapid cooling effect of the sea floor.#EarthCore #seismology #geology #HeatDissipation