Tag Archives: Geology

A 2013 photo of an erupting undersea volcano creating a new island off the coast of Nishinoshima, Japan. The future Hawaiian island of Loihi will resemble this in geological terms.
~100,000-200,000: Exploring Loihi – The Emerging Hawaiian Island

Discover Loihi, an undersea mountain set to become Hawaii's newest island. With a history of seismic activity and significant growth potential, Loihi epitomizes Earth's dynamic geological processes

Photograph of the massive eruptive plume of Mount Pinatubo on the morning of June 12, 1991. This eruption released more ash and dust into the stratosphere than any volcanic eruption since Krakatoa in 1883.
1991: Mount Pinatubo Eruption – Averting a Major Catastrophe

The 1991 Mount Pinatubo eruption, one of the most powerful of the 20th century, led to significant climatic effects and showcased the importance of timely evacuation and volcanic monitoring in reducing fatalities

Main image: Scenic view of Basin and Range National Monument in Nevada. Inset: John McPhee, renowned author of various popular science books on earth sciences.
1982: The Geologic Story of the Basin and Range Province

John McPhee's "Basin and Range" explores the unique geological formation of the Basin and Range Province in the American southwest, offering insights into its complex history and the role of storytelling in science

Main image: A 1930 photograph of German meteorologist and geologist Alfred Wegener. Inset: An early computer-assisted reconstruction of Pangea, fitting many of the current continents together.
1912: Alfred Wegener and the Theory of Continental Drift

Alfred Wegener's theory of continental drift, initially met with skepticism, fundamentally changed geology with the later discovery of tectonic plates

Main image: A photograph taken in 1872 showing boats moored along Marble Canyon. Inset: A photograph of John Wesley Powell alongside a Native American named Tau-gu. Both photos were taken during Powell's second expedition down the Grand Canyon.
1869: John Wesley Powell – Unveiling the Geologic Majesty of the Grand Canyon

John Wesley Powell's groundbreaking expeditions in the late 19th century illuminated the vast geological history of the Grand Canyon, revealing its intricate layers and making it a central figure in geological studies

An illustration from Jules Verne's 1864 science fiction novel, "A Journey to the Center of the Earth."
1864: Jules Verne – Pioneering Science Fiction Through Geological Wonders

Jules Verne, a 19th-century French author, pioneered the science fiction genre by blending emerging scientific theories with imaginative storytelling, focusing on Earth's geological past and hypothetical subterranean adventures

A 1910 photograph of the physicist William Thomson, also known as Lord Kelvin, conducting compass measurements.
1862: Tracing Earth’s Timeline – The Scientific Journey to Determine Its Age

William Thomson, Lord Kelvin, initially estimated Earth's age at 20 to 40 million years, a figure debated by nineteenth-century scientists. The discovery of radioactivity led to a revised estimate of 4.567 billion years, aligning with [...]

Main image: An 1870 photograph of geologist and biologist Louis Agassiz. Inset: An illustration by J. Bettanier of the Matterhorn glacier, located near Zermatt, Switzerland, from Louis Agassiz's 1840 book, "Études sur les Glaciers."
1837: Unveiling the Secrets of Ice Ages – The Contributions of Louis Agassiz

Louis Agassiz's pioneering work in geology led to the discovery of ice ages, explaining the presence of glacial features in currently ice-free regions. His hypothesis that vast ice sheets once covered much of the northern [...]

Green sand, composed of olivine mineral grains, found on a volcanic beach on the island of Hawaii.
1789: Olivine – The Earth’s Mantle’s Gem

Olivine, an abundant magnesium-iron silicate in the Earth's mantle, is key to understanding planetary structures. Its polymorphism and occurrence in volcanic areas, as well as in lunar, Martian, and meteoritic rocks, make it integral to [...]

Main image: Layered rocks at Siccar Point, Scotland, showcasing one of the earliest-recognized unconformities in the geological record. Inset: A sketch from a 1920 geology textbook depicting Scottish geologist James Hutton.
1788: James Hutton’s Discovery of Unconformities

James Hutton revolutionized geology with his observation of angular unconformities in rock layers, leading to the understanding of "deep time" and laying the foundation for modern geological principles

A sample of granite from Victoria, Australia, featuring prominent alkali and plagioclase feldspar minerals (in pinkish-red and gray colors, respectively), along with quartz (shiny) and black mica.
1747: Feldspar – The Backbone of Continental Crust

Feldspar, constituting a major part of the Earth's continental crust, is a framework silicate mineral rich in silicon, oxygen, and elements like calcium, potassium, and sodium. First named by Johan Gottschalk Wallerius in 1747, feldspar's [...]

Main image: Impressive folded and layered rock formations in the Hajar Mountains, Oman. Inset: Cover of "Dissertationis Prodromus" (1669) by Nicolas Steno.
1669: Nicolas Steno – The Father of Stratigraphy

Nicolas Steno, initially trained in anatomy, revolutionized geology by establishing foundational principles of stratigraphy. His work in the 17th century, recognizing fossils embedded in rocks and formulating principles like the Law of Superposition and Principle [...]

The Huaynaputina volcanic crater in southern Peru, marking the remnants of the most significant historical volcanic eruption in South America, albeit relatively unremarkable today.
1600: The Devastating Huaynaputina Eruption

The Huaynaputina volcano in southern Peru witnessed a catastrophic eruption in February 1600, one of the Andes' most severe volcanic events. Preceded by earthquakes and steam eruptions, its explosive Plinian plume significantly impacted the global [...]

An impressive, hand-sized cluster of quartz crystals from Tibet.
c. 300 BCE: Quartz – A Versatile and Abundant Mineral

Quartz, the second most abundant mineral in the Earth's crust, is known for its chemical resilience and diverse forms. Used historically and industrially, it plays a crucial role in various applications, from jewelry to electronics

Salt-encrusted rocks along the shore of the slowly evaporating Dead Sea
c. 3 Million BCE: The Dead Sea – Earth’s Lowest and Saltiest Lake

The Dead Sea, situated in a rift valley created by plate interactions, is the lowest elevation lake on Earth. Hypersaline and with a history shaped by cycles of uplift and subsidence, it has minimal biodiversity [...]

A view from orbit of the Caspian Sea, captured by the MODIS sensor on NASA's Terra satellite in 2003
c. 5.5 Million BCE: The Caspian and Black Seas – Remnants of Ancient Geography

The Caspian and Black Seas, formed from the closure of the Tethys Sea due to the collision of the African and Eurasian plates, are the largest inland lakes with unique characteristics, including salinity and anoxic [...]

An artistic rendering based on geophysical data, depicting the Mediterranean basin just before its separation from the Atlantic Ocean due to the collision between Africa and Southern Europe
c. 6.5 Million BCE: The Evolution of the Mediterranean Sea

The Mediterranean Sea formed from the closure of the Tethys Sea due to the collision of the African and Eurasian plates. This process led to significant volcanic activity and mountain building, followed by a drying [...]

The view from Yavapai Point over the Grand Canyon showcases nearly 2 billion years of Earth’s geologic history, available for detailed study
c. 6.5 Million BCE: The Grand Canyon – A Geological Masterpiece

The Grand Canyon, one of Earth’s most remarkable geological formations, showcases the powerful erosive force of liquid water over time. It is a prime example of how rivers and streams can shape even the toughest [...]

Spectacular sand dunes in the Sahara Desert, the largest non-polar desert in the world
c. 7 Million BCE: The Sahara Desert – Earth’s Largest Hot Desert

The Sahara, Earth's largest non-polar desert, is characterized by extreme temperatures and low rainfall, formed due to the shifting of continental plates and the closing of the Tethys Sea, resulting in a landscape predominantly shaped [...]

An illustrative depiction showing the Earth's crust being split by plate tectonics in the East African Rift Zone, with the Horn of Africa and Somalia on the right, and the Nile River on the left, predicting the formation of a new ocean basin that will divide Africa into two plates in about 10 million years
c. 30 Million BCE: The East African Rift Zone – Earth’s Dynamic Crust

The East African Rift Zone, a result of continental rifting and mantle plume activity, is actively splitting the African continent, with predictions of forming two new plates and a new ocean basin in about 10 [...]