A database of the geologic map of the Katmai Volcanic Cluster as described in the original abstract: This digital publication contains all the geologic map information used to publish U.S. Geological Survey Geologic Investigations Map Series I-2778 (Hildreth and Fierstein, 2003). This is a geologic map of the Katmai volcanic cluster on the Alaska Peninsula (including Mount Katmai, Trident Volcano, Mount Mageik, Mount Martin, Mount Griggs, Snowy Mountain, Alagogshak volcano, and Novarupta volcano), and shows the distribution of ejecta from the great eruption of June, 1912 at Novarupta. Widely scattered erosional remnants of volcanic rocks, unrelated to but in the vicinity of the Katmai cluster, are also mapped. Distribution of glacial deposits, large landslides, debris avalanches, and surficial deposits are a snapshot of an ever-changing landscape.

The 2018 lower East Rift Zone eruption of Kilauea Volcano began in the late afternoon of 3 May, with fissure 1 opening and erupting lava onto Mohala Street in the Leilani Estates subdivision, part of the lower Puna District of the Island of Hawai'i. For the first week of the eruption, relatively viscous lava flowed only within a kilometer (0.6 miles) of the fissures within Leilani Estates, before activity shifted downrift (east-northeast) and out of the subdivision during mid-May. Around 18 May, activity along the lower East Rift Zone intensified, and fluid lava erupting at higher effusion rates from the downrift fissures reached the ocean within two days. Near the end of May, this more vigorous activity shifted back uprift into Leilani Estates, where fissure 8 reactivated with lava fountains feeding several 'a'a flows. The southernmost flow lobe developed into a well-defined lava channel and reached the ocean at Kapoho Bay - 11 kilometers (7 miles) away - on 3 June. Fissure 8 continued supplying this lava channel for more than two months, constructing an approximately 3.5-square-kilometer (1.4-square-mile) lava delta along the coastline. Over 4 and 5 August, activity at fissure 8 waned and flow in the lava channel came to a halt, only to be followed by weak activity within the vent in late August and early September. By then, the eruption had covered 35.5 square kilometers (13.7 square miles) of the lower Puna District with lava. In this report, the authors have sought to chronicle this sequence of events using geospatial data in the form of an Esri file geodatabase, Esri shapefiles, and Google Earth KMZs.

The 2018 lower East Rift Zone eruption of Kilauea Volcano began in the late afternoon of 3 May, with fissure 1 opening and erupting lava onto Mohala Street in the Leilani Estates subdivision, part of the lower Puna District of the Island of Hawai'i. For the first week of the eruption, relatively viscous lava flowed only within a kilometer (0.6 miles) of the fissures within Leilani Estates, before activity shifted downrift (east-northeast) and out of the subdivision during mid-May. Around 18 May, activity along the lower East Rift Zone intensified, and fluid lava erupting at higher effusion rates from the downrift fissures reached the ocean within two days. Near the end of May, this more vigorous activity shifted back uprift into Leilani Estates, where fissure 8 reactivated with lava fountains feeding several 'a'a flows. The southernmost flow lobe developed into a well-defined lava channel and reached the ocean at Kapoho Bay - 11 kilometers (7 miles) away - on 3 June. Fissure 8 continued supplying this lava channel for more than two months, constructing an approximately 3.5-square-kilometer (1.4-square-mile) lava delta along the coastline. Over 4 and 5 August, activity at fissure 8 waned and flow in the lava channel came to a halt, only to be followed by weak activity within the vent in late August and early September. By then, the eruption had covered 35.5 square kilometers (13.7 square miles) of the lower Puna District with lava. In this report, the authors have sought to chronicle this sequence of events using geospatial data in the form of an Esri file geodatabase, Esri shapefiles, and Google Earth KMZs.

The geologic map database in this data release is a reproduction of the U.S. Geological Survey Professional Paper 1762: Volcanic Processes and Geology of Augustine Volcano, Alaska, Waitt and Begét (2009). The database consists of a geologic map and one structural cross section that conform to the National Geologic Map Schema (GeMS). These data supersede USGS Data Series 677: Database for Volcanic Processes and Geology of Augustine Volcano, Alaska, McIntire and others, 2012. Augustine Island (volcano) in lower Cook Inlet, Alaska, has erupted repeatedly in late-Holocene and historical times. Eruptions typically beget high-energy volcanic processes. Most notable are bouldery debris avalanches containing immense angular clasts shed from summit domes. Coarse deposits of these avalanches form much of Augustine's lower flanks. This geologic map, at 1:25,000, show the distribution and relations of volcanic units at Augustine Volcano. This database does not reproduce all elements of the original publication. Omissions include the chart and figures showing the measured sections on Augustine Island and Shuyak Island, Alaska, and the chart and diagram for the correlation of map units. Versions of these data are provided in open-access formats that are compatible with a broad range of geospatial applications. The open-access data is derived from the file geodatabase using a python script downloadable at https://github.com/doi-usgs/gems-tools-pro. Vector data are provided as shapefiles and tabular data are provided in *.txt and *.csv formats. Any shapefiles derived from the geodatabase may have prefixes of GM_[filename] and CS_[filename] indicating features are part of the geologic map or a structural cross section, respectively. Attribute table field names may be automatically abbreviated or shortened to 10 characters to conform with the shapefile format. The annotation feature class (a native format of the Esri file geodatabase) for the structural cross section is omitted because there is no equivalent open file type. Symbology layer files (*.lyrx) are provided for symbolizing the map using the intended symbols, lines, fills and patterns and a copy of the database. We recommend Esri software users set the display reference scale between 1:10,000 and 1:24,000 for optimal display of symbology, and enable the Maplex labeling engine for optimal display of labels. Users of this database are highly encouraged to cross reference this database with the original publication.

The geologic map database in this data release is a reproduction of the U.S. Geological Survey Professional Paper 1762: Volcanic Processes and Geology of Augustine Volcano, Alaska, Waitt and Begét (2009). The database consists of a geologic map and one structural cross section that conform to the National Geologic Map Schema (GeMS). These data supersede USGS Data Series 677: Database for Volcanic Processes and Geology of Augustine Volcano, Alaska, McIntire and others, 2012. Augustine Island (volcano) in lower Cook Inlet, Alaska, has erupted repeatedly in late-Holocene and historical times. Eruptions typically beget high-energy volcanic processes. Most notable are bouldery debris avalanches containing immense angular clasts shed from summit domes. Coarse deposits of these avalanches form much of Augustine's lower flanks. This geologic map, at 1:25,000, show the distribution and relations of volcanic units at Augustine Volcano. This database does not reproduce all elements of the original publication. Omissions include the chart and figures showing the measured sections on Augustine Island and Shuyak Island, Alaska, and the chart and diagram for the correlation of map units. Versions of these data are provided in open-access formats that are compatible with a broad range of geospatial applications. The open-access data is derived from the file geodatabase using a python script downloadable at https://github.com/doi-usgs/gems-tools-pro. Vector data are provided as shapefiles and tabular data are provided in *.txt and *.csv formats. Any shapefiles derived from the geodatabase may have prefixes of GM_[filename] and CS_[filename] indicating features are part of the geologic map or a structural cross section, respectively. Attribute table field names may be automatically abbreviated or shortened to 10 characters to conform with the shapefile format. The annotation feature class (a native format of the Esri file geodatabase) for the structural cross section is omitted because there is no equivalent open file type. Symbology layer files (*.lyrx) are provided for symbolizing the map using the intended symbols, lines, fills and patterns and a copy of the database. We recommend Esri software users set the display reference scale between 1:10,000 and 1:24,000 for optimal display of symbology, and enable the Maplex labeling engine for optimal display of labels. Users of this database are highly encouraged to cross reference this database with the original publication.

Alamagan Volcano is a Quaternary stratovolcano along the Mariana Arc, an active subduction zone in the western Pacific Ocean. Although primarily submerged, its peak reaches above sea level, with subaerially-exposed volcanic deposits dating back through the Holocene to the late Pleistocene. These feature data represent such deposits and other geologic features of Alamagan Volcano, describing its interpreted eruptive history.