The image of Lassen Peak reflects in the waters of Manzanita Lake. Photo submitted

New book focuses on national park’s geology

The Earth is not always quiet. An isolated region of Northeastern California offers a land of boiling springs, steaming sulfur vents, mud pots and volcanoes. The boisterous geology of the Southern Cascades is defined by Lassen Volcanic National Park. A complex and compelling geologic story is told in “The Geology of the Lassen Country,” a new book by R. Forrest Hopson and Michael A. Clynne.

While Lassen Country is not a formal name, it is used to describe both the national park and surrounding areas. The area encompasses a variety of fascinating geologic features set in a unique volcanic landscape. Did you know this is the site of California’s most recent volcanic eruption?

Volcanoes come in all shapes and sizes, and in the Lassen Country an amazing six volcano types are found. These include stratovolcanoes, volcanic domes, shield volcanoes, cinder cones, lava cones, and one explosion pit crater. In addition, Lassen Country contains the most active and spectacular hot spring fields in the Cascade Range. The mountains here feature crystal clear lakes and streams, forested mountain slopes, and a wide range of plant and animal life.

This new book explores the geology and geologic evolution of the area, providing an up-to-date source of information specific to Lassen Country. This is all based on Michael Clynne’s life work. He has been piecing together the geologic story of the Lassen Country for more than 30 years.

“Recent work by the U.S. Geological Survey has refined and built on previous geologic interpretations of the Lassen Country. This book is exciting to me because it makes the story accessible to everyone,” said co-author Michael A. Clynne.

“This book is important because it offers an up-to-date synopsis of the geology of Lassen Volcanic National Park. It explains how Lassen Peak is part of a long-lived magmatic system, called the Lassen Volcanic Center, where volcanism has produced a series of eruptive events creating what we see today” said co-author R. Forrest Hopson.

In addition to geology, the book offers cultural and historical notes about the region, a mile-by-mile geologic tour through Lassen Volcanic National Park to Old Station, and eight detailed hikes to get out and explore the amazing regional geology of Lassen Country.

Backcountry Press, in Humboldt County, California, publishes and distributes the book. The companion website,, offers supplemental materials and more details about the book. Geology of the Lassen Country is available at and from independent bookstores including those run by the Lassen Association in the National Park.

Charles Darwin once said, “Geologizing in a volcanic country is most delightful; besides the interest attached to itself, it leads you into the most beautiful and retired spots.” Get out this summer and explore the volcanic country in our own backyard.