How the Mountains Grew: A New Geological History of North America John Dvorak August 2021 Pegasus Books, an imprint of Simon & Schuster Themes: Science, Nature, Ecosystems, Geology, Geologic History, Mountains
- In the 1960s, the theory of plate tectonics became widely accepted. However, it was not able to explain the existence of the Black Hills or the diamonds of Arkansas. The intertwining of geology with other traditional and emerging sciences is needed to trace the entire span of geological history.
- On August 17, 2017, the first gravitational waves were detected in the direction of the constellation Hydra. This confirmed the collision of neutron stars. These collisions are responsible for most of the heavier elements in the universe such as gold and silver. Prior to this discovery, these collisions were purely theoretical.
- In 2015, the International Commission on Stratigraphy determined that the 4.030 billion year old Acasta Gneiss found in the remote Northwest Territories of Canada represents a major milestone in geologic history marking the beginning of the Archean Eon. It’s considered to be the oldest known rock on Earth.
- Luis and Walter Alvarez published a paper in 1980 hypothesizing that an extraterrestrial body caused the mass extinction of the dinosaurs. In 2016, a scientific drilling project penetrated the seafloor identifying the Chicxulub impact crater.
- In geodynamics, delamination is the loss of the lowermost lithosphere from its tectonic plate. Asthenosphere rises to replace the sinking lithosphere. This process causes uplifts and sometimes volcanism playing an important role in the continuing “growth spurt” of mountains such as the Sierra Nevada. Seismic tomography allows geoscientists to generate images from the crust to the core. 5) In 2019, delamination was found through seismic tomography in the Appalachian Mountains.
- In 2019, a fossilized forest containing palm-like trees was found near Cairo, New York demonstrating that complex forests existed at least as early as 388 million years ago.
- Although working groups at the major geological societies have not yet recognized the Anthropocene as the current geological epoch, the term as been used informally for a couple decades. The benchmarks for this new epoch include the impact by humans on the natural world. From human-made rock such as concrete and bricks to plastic fragments, human have already made profound changes in the rock record.