USGS Science⌕ Search

Geology topics

James W. Hendley

Publications and source records attributed to James W. Hendley.

At least 19 recordsLinked to original sources
USGS2014

California's restless giant: The Long Valley Caldera

Scientists have monitored geologic unrest in the Long Valley, California, area since 1980. In that year, following a swarm of strong earthquakes, they discovered that the central part of the Long Valley Caldera had begun actively rising. Unrest in the area persists today. The U.S. Geological Survey (USGS) continues to provide the public and civil authorities with current information on the volcanic hazard at Long Valley and is prepared to give timely warnings of any impending eruption.

California↗
USGS2014

Progress toward a safer future since the 1989 Loma Prieta earthquake

The 1989 Loma Prieta earthquake interrupted several decades of seismic tranquility in the San Francisco Bay Area. It caused damage throughout the region and was a wakeup call to prepare for potentially even more damaging future quakes. Since 1989, the work of the U.S. Geological Survey and many other organizations has improved the understanding of the seismic threat in the Bay Area, promoted awareness of earthquake hazards, and contributed to more effective strategies to reduce earthquake losses. These collective efforts will help reduce the impact of future large earthquakes in the Bay Area.

California↗
USGS2014

A sight "fearfully grand": eruptions of Lassen Peak, California, 1914 to 1917

On May 22, 1915, a large explosive eruption at the summit of Lassen Peak, California, the southernmost active volcano in the Cascade Range, devastated nearby areas and rained volcanic ash as far away as 280 miles to the east. This explosion was the most powerful in a series of eruptions during 1914–17 that were the last to occur in the Cascade Range before the 1980 eruption of Mount St. Helens, Washington. A century after the Lassen eruptions, work by U.S. Geological Survey (USGS) scientists in cooperation with the National Park Service is shedding new light on these events.

California↗
USGS2003

Bacterial contamination at Huntington Beach, California — Is it from a local offshore wastewater outfall?

During the summers of 1999 and 2000, beaches at Huntington Beach, California, were repeatedly closed to swimming because of high bacteria levels in the surf zone. The city’s beaches are a major recreational and commercial resource, normally attracting millions of visitors each summer. One possible source of the bacterial contamination was the Orange County Sanitation District’s sewage outfall, which discharges treated wastewater 4.5 miles offshore at a depth of 200 feet. Scientists from the U.S. Geological Survey and cooperating organizations have been investigating whether ocean currents and waves transport the wastewater to the beaches. These studies indicate that bacteria from the outfall are not a significant source of the beach contamination.

California↗