Lamplugh Glacier is located in Glacier Bay National Park and Preserve, about 54 miles (87 km) northwest of Gustavus, Alaska. The Lamplugh flows out of the Brady Icefield and trends north for 16 miles (26 km) to its terminus in Johns Hopkins Inlet. The glacier was named by Lawrence Martin of the U.S. Geological Survey around 1912 for the English geologist George William Lamplugh, who visited Glacier Bay in 1884.
The Lamplugh Glacier is about 0.75 miles (1.2 km) wide at the terminus. The ice face rises to a height of 150–160 feet (46–49 m). The flow rate of the glacier is estimated at 900–1,000 feet (270–300 m) per year. The terminus is currently receding by calving in the central part of the ice face. The western third and maybe also the eastern third of the terminus are grounded, and only at the highest tides does saltwater reach the entire glacial toe. A large subglacial stream flows from the central part of the terminus, but its position shifts laterally from year to year, sometimes in response to the build-up of fluvial sediment as a small delta that can be seen at low tide. This turbid subglacial stream discharges large volumes of sediment-laden water into the fjord.
In early July 2016, a massive landslide spread rocky debris more than 6 miles (10 km) across the upper Lamplugh Glacier. The source of the slide appears to be a peak on the west side of the glacier that was more than 6,500 feet (1,982 m) high. The Lamont-Doherty Earth Observatory estimated the slide involved more than 132 million tons of rock. The slide caused seismic tremors that first registered at magnitude 2.9, according to the Alaska Earthquake Center, but that was later updated to a magnitude 5.5. Read more here and here. Explore more of Lamplugh Glacier here: