How did the Himalayas get to be Earth’s highest mountain range?
In my last four posts, I described the 21-day trek we did in the Everest region in November 2021, including some of our geologic observations along the way. In this final post, I explain how these mountains evolved to achieve such immense size and beauty. Here's how Earth's continents were distributed 50 million years ago (Ma). At about 200 Ma,...
Trekking in the Khumbu region of the Nepal Himalayas, Part 4: from Gokyo back to Lukla
The last leg of our 21-day trek extended west from Goyko to cross the Renjo La (pass), then south down the Bhote Koshi valley back to Namche, and finally down the Dudh Koshi valley to Lukla, where we flew back to Kathmandu. Please see my first post for a map of the trek, including this last leg: https://landscapes-revealed.net/trekking-in-the-khumbu-region-of-the-nepal-himalayas-part-1-from-kathmandu-to-namche/. The area...
Trekking in the Khumbu region of the Nepal Himalayas, Part 3: to Everest Base Camp and Goyko
From Chhukhung (end of Part 2 post: https://landscapes-revealed.net/trekking-in-the-khumbu-region-of-the-nepal-himalayas-part-2-all-hail-to-ama-dablam/), our next destination was Gorak Shep and Everest Base Camp. We trekkers split into two groups: one group hiked from Chhukhung over the Kongma La (pass) to Lobuche; the other group hiked down the valley from Chhukhung to Dingboche, then followed another valley northward to Lobuche. See my first post for a...
Trekking in the Khumbu region of the Nepal Himalayas, Part 2: All hail to Ama Dablam
This second post about trekking in our planet's highest mountains is a tribute to Ama Dablam, the mountain we saw all along the route to the northeast from Namche to Chhukhung, where we reached the highest elevation of the trek. As we continued uphill, we found steeper trails, more primitive lodges, and lots of in-your-face geology! Link to my first...
Trekking in the Khumbu region of the Nepal Himalayas, Part 1: from Kathmandu to Namche
What geologist doesn’t yearn to experience the grandeur of our planet’s highest mountain range? Certainly, I was exhilarated by the opportunity to gaze upon the breathtaking landscapes of the Himalayas, formed during the past 50 million years, as the sub-continent of India has been colliding with the continent of Asia. We spent the month of November 2021 in Nepal—the main...
John Day Fossil Beds National Monument—climate
My previous post about paleontology explored how plants and animals changed during the 44-million-year time period represented in the John Day Fossil Beds. The evolution of species, in general, occurs because species eventually become extinct and new species arise to take their places. Today, human activities are contributing to organisms' extinction, but there are many natural factors that have caused...
John Day Fossil Beds National Monument—paleontology
Paleontology is the study of plant and animal fossils to understand how life has evolved through geologic time. The John Day Fossil Beds are a world-class locality for such studies. According to Dr. Ralph W. Chaney, a paleontologist at the University of California Berkeley (UCB) who worked in the area from the 1920s through the 1960s: “No region in the...
John Day Fossil Beds National Monument—stratigraphy
The John Day Fossil Beds is located in north-central Oregon. It was established as a national monument in 1974. The region has one of the world's most complete records of fossils during the Age of Mammals, a period of time also known as the Cenozoic Era (past 66 million years). There will be three blog posts: (1) stratigraphy—how layers of...
Mount Hood — Oregon’s highest peak
After smoky air deterred us from backpacking locations in northern California, we headed north to Mount Hood. There, the Timberline Trail promised an interesting trek around Oregon's highest mountain (3426 m / 11,240 ft), located about 80 km (50 miles) east of Portland. Mount Hood is the northernmost Cascade Range volcano in Oregon. See my post about Crater Lake for...
Why are there so many hills in San Francisco?
Any visitor to San Francisco will be impressed by the number of hills and how they contribute to the overall beauty of the city. People (like me) who have resided in San Francisco have found biking and walking routes to avoid the steepest hills, and have appreciated how the hills compartmentalize the city into distinctive neighborhoods and provide stunning views....
Plate tectonics 101—What happens at hot spots?
As seen in my last three posts, most geologic action occurs at the boundaries between lithospheric plates. But in some places we find active volcanoes and earthquakes that are not at plate boundaries. This post will explore these places, where geologic action is occurring at so-called "hot spots". What are these features; what causes them; and what are some of...
Plate tectonics 101—What happens when plates slide past each other?
Oceanic crust is created at divergent plate boundaries and destroyed at convergent boundaries, but transform boundaries cause neither; rather, they transform motion between other types of plate boundaries, enabling plates to move about efficiently on our spherical planet. In this post, we will explore various examples. The majority of transform boundaries are found in the ocean, where they separate segments...
About the Blogger
Karen (here with Mt. Shasta in background) is a geology professor emerita who aims to provide a "pocket geologist" for world travelers. Follow the blog to explore the landscapes of our planet and figure out what causes them to look the way they do.