How have geological events shaped the course of human history?
The GeoHammers are cataclysms that affect earth at various times. These are real world events, documented throughout the geological record. CE means 'Common Era', usually a substitute for AD; BCE means 'Before Common Era', usually a substitute for BC. The GeoHammers are listed in reverse chronological order; most recent events first, most ancient events last. Several non-GeoHammer events (such as the flooding of the Black Sea) are included for modern/historical comparisons of major events in human history. These non-GeoHammer events also help allow for global correlations in events; what seems to be a local disaster may be part of a larger, global catastrophe. References are given where available.
This page was originally designed to look for astronomical 'hammers' that impacted life on earth, but may soon be renamed to 'biohammers' that have altered and shaped life on earth in dramatic ways. Geology and biology and human history all interact in ways not so obvious to the Geologist or the Archaeologist, and so we detail both events here. The hammer concept comes from Larry Niven and Jerry Pournelle's book Lucifer's Hammer, published in 1977.
The VEI, or Volcanic Explosivity Index, runs along a scale of 1-8, with a 5 being an ejecta volume of greater than one kilometer cubed.
The Geohammers are divided into four areas of time, where Common Era replaces Anno Dominique, and Before Common Era replaces Before Christ.
Common Era CE Events
Thousands of Years Before Common Era K BCE Events
Millions of Years Before Common Era M BCE Events
Billions of Years Before Common Era B BCE Events
Smithsonian Institution Volcano Database – containing some 10k years worth of volcanic data. http://www.volcano.si.edu/
Ludlow et alia found a strong correlation to volcanic eruptions and famines and other cold-weather events in Ireland while poring over the Irish Chronicles and comparing them to ice core samples.
Francis Ludlow, Alexander R Stine, Paul Leahy, Enda Murphy, Paul A Mayewski, David Taylor, James Killen, Michael G L Baillie, Mark Hennessy and Gerard Kiely. 2013. “Medieval Irish chronicles reveal persistent volcanic forcing of severe winter cold events, 431–1649 CE” Environmental Research Letters Vol 8, No 2. doi:10.1088/1748-9326/8/2/024035