Harold Tobin

@haroldtobin.bsky.social

4028 Followers 266 Following

UW prof and director of the Pacific Northwest Seismic Network. WA State Seismologist. All about subduction zones and very messed up rocks.

Screenshot of text from the article reading: “Tobin said scientists are still weighing whether Wednesday’s sequence was indeed a doublet, though the USGS described it as such. “It’s actually a subject of lots of discussion right now among seismologists about whether to call it two earthquakes or one earthquake with multiple phases or pulses of energy,” Tobin said, adding that the debate was a little semantic.”
10 new PhDs in full purple and gold academic regalia standing in front of the fountain at University of Washington.
A map of the Juan de Fuca plate region of the Pacific Ocean, with the coast of BC, WA, and OR on the right. 18 orange dots show the locations of earthquakes on April 12, 2026, all in the spreading ridge vicinity. Black lines show the plate boundaries, including the JdF ridge, the Cascadia subduction zone, and the Blanco Transform Fault.
Satellite image based map of central to northern Chile and Peru, with epicenter shown just offshore at 28.6 S latitude. Taken from USGS event page linked in the post.
March 11, 2011 tsunami washing ashore on the Sendai coastal plain, sweeping into a coastal village. I visited this spot a few months later in August, 2011.
Cover of the March-April 2026 issue of the Geological Society of America Bulletin, including a full-cover photograph of a wide-view scene of bare rock and snow, with a geologist at work highlighted by low-angle sun. Photo is from summer of 2024 field work at the Lakes of the Gods, Olympic National Park.
Screenshot of NHK News TV at 01:22 JST, 8:22 PST. Table on screen shows actual observed tsunami inundation up to 70 cm in coastal ports.
Vertical evacuation structure in Kure, where 400 people can get to 28 meters above sea level.
Two geologists pointing out enormous coastal outcrops of steeply-dipping ribbon chert.
Two geologists with hiking gear standing at an overlook, looking at a rocky valley and in the distance, the Geri-freki glacier and surrounding peaks. In Olympic National Park.
Color map of the entire Pacific Ocean, with colors representing tsunami wave height in the open ocean, and contour lines showing the tsunami wave front in elapsed hours after the earthquake.
Image of quoted text: "Tobin said the successful tsunami warning Tuesday should spur investment in seafloor sensors and seismic monitoring stations offshore along the subduction zone. “This shows the value and importance of NOAA and the USGS in these times where some of these government agencies have come into question,” he said. “We wouldn’t have had a tsunami warning if it weren’t for NOAA, and the next one could be a closer event. They showed their value.”
A graph of the water levels at a tide gauging station in Port Angeles Washington. Blue line shows predicted tide in feet above mean low water; red line shows observed water level. Yuo can clearly see the oscillations of the tsunami from Kamchatka, up to ~2 feet amplitude.
map of southern Kamchatka peninsula, with earthquake epicenters plotted offshore Petropavlovsk. Russia.
Screenshot of Washington post headline reading “DOGE loses control over government grants website, freeing up billions”
a map of the offshore region of the Cascadia subduction zone from 45˚ to 48.5˚ north, showing the bathymetry and both recently-active and inactive fault systems, including splay faults and strike-slip faults. Green shaded areas delineate an active fault swath in the the outermost 20-30 km of the accretionary wedge, and an inactive swath landward of that.
Mt. St. Helens, viewed aerially from the west, before 1980, 2950 m (9677') in elevation. Almost all of this formed through eruptions since 1980. Mt. Adams in distance on left. (USGS/public domain)
Sidewalk filled with bricks and damaged 1940s-era parked cars in aftermath of Olympia earthquake, Pioneer Square, Seattle. Courtesy of Museum of History and Industry, Seattle.
Map clipping of part of Washington state showing a star at earthquake epicenter location. (mag 3.7 quake on April 6 at 8:15 am local time).
Aerial video of the Wrangell-St. Elias region with vast expanse of snow covered peaks, numerous glaciers and ice streams.
A map of the Indian Ocean region that graphically depicts the 2004 Sumatra tsunami runups in meters in various places that ring the ocean basin.
Scientists gathered around a table on the drilling vessel Chikyu.
Excerpt from a video on display at the Smithsonian about the NanTroSEIZE scientific drilling project of IODP.
Close-up of label on a bottle of ‘Subduction Red’ from Syncline Winery in Washington state.
The alpine Lakes of the Gods in Olympic National Park viewed from a high hillside perspective, with the White glacier and Mt. Tom in the distance, all under a bright blue sky. Geologist sits in the foreground seen from behind, contemplating the outcrops of melange rock exhumed from the depths of the Cascadia subduction zone.
Puffy clouds, meandering river reflecting the sun, and landscape. Taken in September from an airplane window seat high above some midwestern location.
13 geologists posing on a spectacular seaside outcrop of fault rocks, South Beach, San Juan Island, Washington, USA
An airborne photo of Tacoma and the South Sound in foreground, and (from left to right) Mt. Rainier/Tahoma, Mt. Adams/Pahto, Mt. Hood/Wy’east in the far distance, and Mt. St. Helens/Loowit.
Amazing 6 meter deep trench into the Chelungpu fault surface rupture, with the fault plabe pointed out in 2004 by me, with Prof. Jyr-Ching Hu of NTU.
Prof. Bruce Shyu explains the paleoseismic significance of the notches from the mouth of a cave, with scientists looking on. Rocks are an amazing Miocene age volcanic breccia.
Map graphic depicting the Cascadia subduction zone with a growing megathrust earthquake and GPS vectors from nearby onland stations. https://www.iris.edu/hq/inclass/downloads/optional/1487
4 people from a field crew at Mt St Helens in 1984, crater in the background.
Hiker seeing first moments of Mt. St. Helens eruption and falling down in astonishment.
Sheared basalt pillows and pelagic sediments, decorated with many veins - the famous Rodeo Cove accreted seamount.