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Hawaiian Volcano Observatory record book 1938

The Hawaiian Volcano Observatory (HVO) record books are annual journals in which field observations of eruptive activity at Kīlauea and Mauna Loa volcanoes, on the Island of Hawaiʻi, were compiled by HVO staff for most years from 1912 through early 1966. In addition to descriptive observations, the record books also contain hundreds of annotated photographs and sketches, as well as temperature and transit measurements. When photographs are included, the camera settings and film types used are noted. The field notes, sketches, and photographs used to compile the record books provide an unparalleled record of eruptive activity and were the basis for published newspaper reports and periodic bulletins, such as the Hawaiian Volcano Observatory bulletins and The volcano letter . HVO staff also painstakingly prepared a second copy of each early record book, virtually identical to the original, complete with photographs and sketches. The original version of the record book was kept at HVO, while the duplicate went to the Hawaiian Volcano Research Association, which was created by a group of Honolulu, Hawaiʻi, businessmen to promote HVO’s work. The Hawaiian Volcano Research Association, which dissolved decades ago, held the duplicate books in Honolulu, where they were more readily accessible to the public. After 1923, HVO stopped duplicating the books—at least, no duplicate records for subsequent years have been found. During the decade of the 1940s, preparation of the record books stopped altogether. In 1952, compilation of the record books resumed and continued, with long gaps, until early 1966. Entries in these later volumes are sparse, and these books are little more than photo albums of the episodic eruptions of Kīlauea. The original record books were held at HVO and, later, at Hawai‘i Volcanoes National Park. In 1972, the original record books for the years 1912 through 1939 were transferred to the Bishop Museum, in Honolulu, for safekeeping. These record books are now stored in archival boxes at that institution (accession number 172.265). The duplicate set of record books held by the Hawaiian Volcano Research Association were bound into volumes at an unknown date and turned over to the U.S. Geological Survey. This set of record books, spanning 1912 through 1923, is now housed in the rare book room of the U.S. Geological Survey Library in Reston, Virginia (catalog number 220(950) H3d). The record books for 1952 through early 1966 remain in storage at HVO. After 1955, typed annotations were no longer placed in the record books, and only photographs, most with captions, were included. Although the volumes titled “Record Book” end with the 1955 volume, the photograph albums that followed are similar, and the record book designation is retained for simplicity. Note that the photographs in these albums were not all originally arranged in chronological order.

Hawaii↗

Hawaiian Volcano Observatory record book 1939

The Hawaiian Volcano Observatory (HVO) record books are annual journals in which field observations of eruptive activity at Kīlauea and Mauna Loa volcanoes, on the Island of Hawaiʻi, were compiled by HVO staff for most years from 1912 through early 1966. In addition to descriptive observations, the record books also contain hundreds of annotated photographs and sketches, as well as temperature and transit measurements. When photographs are included, the camera settings and film types used are noted. The field notes, sketches, and photographs used to compile the record books provide an unparalleled record of eruptive activity and were the basis for published newspaper reports and periodic bulletins, such as the Hawaiian Volcano Observatory bulletins and The volcano letter . HVO staff also painstakingly prepared a second copy of each early record book, virtually identical to the original, complete with photographs and sketches. The original version of the record book was kept at HVO, while the duplicate went to the Hawaiian Volcano Research Association, which was created by a group of Honolulu, Hawaiʻi, businessmen to promote HVO’s work. The Hawaiian Volcano Research Association, which dissolved decades ago, held the duplicate books in Honolulu, where they were more readily accessible to the public. After 1923, HVO stopped duplicating the books—at least, no duplicate records for subsequent years have been found. During the decade of the 1940s, preparation of the record books stopped altogether. In 1952, compilation of the record books resumed and continued, with long gaps, until early 1966. Entries in these later volumes are sparse, and these books are little more than photo albums of the episodic eruptions of Kīlauea. The original record books were held at HVO and, later, at Hawai‘i Volcanoes National Park. In 1972, the original record books for the years 1912 through 1939 were transferred to the Bishop Museum, in Honolulu, for safekeeping. These record books are now stored in archival boxes at that institution (accession number 172.265). The duplicate set of record books held by the Hawaiian Volcano Research Association were bound into volumes at an unknown date and turned over to the U.S. Geological Survey. This set of record books, spanning 1912 through 1923, is now housed in the rare book room of the U.S. Geological Survey Library in Reston, Virginia (catalog number 220(950) H3d). The record books for 1952 through early 1966 remain in storage at HVO. After 1955, typed annotations were no longer placed in the record books, and only photographs, most with captions, were included. Although the volumes titled “Record Book” end with the 1955 volume, the photograph albums that followed are similar, and the record book designation is retained for simplicity. Note that the photographs in these albums were not all originally arranged in chronological order.

Hawaii↗

Hawaiian Volcano Observatory record book 1952

The Hawaiian Volcano Observatory (HVO) record books are annual journals in which field observations of eruptive activity at Kīlauea and Mauna Loa volcanoes, on the Island of Hawaiʻi, were compiled by HVO staff for most years from 1912 through early 1966. In addition to descriptive observations, the record books also contain hundreds of annotated photographs and sketches, as well as temperature and transit measurements. When photographs are included, the camera settings and film types used are noted. The field notes, sketches, and photographs used to compile the record books provide an unparalleled record of eruptive activity and were the basis for published newspaper reports and periodic bulletins, such as the Hawaiian Volcano Observatory bulletins and The volcano letter . HVO staff also painstakingly prepared a second copy of each early record book, virtually identical to the original, complete with photographs and sketches. The original version of the record book was kept at HVO, while the duplicate went to the Hawaiian Volcano Research Association, which was created by a group of Honolulu, Hawaiʻi, businessmen to promote HVO’s work. The Hawaiian Volcano Research Association, which dissolved decades ago, held the duplicate books in Honolulu, where they were more readily accessible to the public. After 1923, HVO stopped duplicating the books—at least, no duplicate records for subsequent years have been found. During the decade of the 1940s, preparation of the record books stopped altogether. In 1952, compilation of the record books resumed and continued, with long gaps, until early 1966. Entries in these later volumes are sparse, and these books are little more than photo albums of the episodic eruptions of Kīlauea. The original record books were held at HVO and, later, at Hawai‘i Volcanoes National Park. In 1972, the original record books for the years 1912 through 1939 were transferred to the Bishop Museum, in Honolulu, for safekeeping. These record books are now stored in archival boxes at that institution (accession number 172.265). The duplicate set of record books held by the Hawaiian Volcano Research Association were bound into volumes at an unknown date and turned over to the U.S. Geological Survey. This set of record books, spanning 1912 through 1923, is now housed in the rare book room of the U.S. Geological Survey Library in Reston, Virginia (catalog number 220(950) H3d). The record books for 1952 through early 1966 remain in storage at HVO. After 1955, typed annotations were no longer placed in the record books, and only photographs, most with captions, were included. Although the volumes titled “Record Book” end with the 1955 volume, the photograph albums that followed are similar, and the record book designation is retained for simplicity. Note that the photographs in these albums were not all originally arranged in chronological order.

Hawaii↗

Hawaiian Volcano Observatory record book 1953

The Hawaiian Volcano Observatory (HVO) record books are annual journals in which field observations of eruptive activity at Kīlauea and Mauna Loa volcanoes, on the Island of Hawaiʻi, were compiled by HVO staff for most years from 1912 through early 1966. In addition to descriptive observations, the record books also contain hundreds of annotated photographs and sketches, as well as temperature and transit measurements. When photographs are included, the camera settings and film types used are noted. The field notes, sketches, and photographs used to compile the record books provide an unparalleled record of eruptive activity and were the basis for published newspaper reports and periodic bulletins, such as the Hawaiian Volcano Observatory bulletins and The volcano letter . HVO staff also painstakingly prepared a second copy of each early record book, virtually identical to the original, complete with photographs and sketches. The original version of the record book was kept at HVO, while the duplicate went to the Hawaiian Volcano Research Association, which was created by a group of Honolulu, Hawaiʻi, businessmen to promote HVO’s work. The Hawaiian Volcano Research Association, which dissolved decades ago, held the duplicate books in Honolulu, where they were more readily accessible to the public. After 1923, HVO stopped duplicating the books—at least, no duplicate records for subsequent years have been found. During the decade of the 1940s, preparation of the record books stopped altogether. In 1952, compilation of the record books resumed and continued, with long gaps, until early 1966. Entries in these later volumes are sparse, and these books are little more than photo albums of the episodic eruptions of Kīlauea. The original record books were held at HVO and, later, at Hawai‘i Volcanoes National Park. In 1972, the original record books for the years 1912 through 1939 were transferred to the Bishop Museum, in Honolulu, for safekeeping. These record books are now stored in archival boxes at that institution (accession number 172.265). The duplicate set of record books held by the Hawaiian Volcano Research Association were bound into volumes at an unknown date and turned over to the U.S. Geological Survey. This set of record books, spanning 1912 through 1923, is now housed in the rare book room of the U.S. Geological Survey Library in Reston, Virginia (catalog number 220(950) H3d). The record books for 1952 through early 1966 remain in storage at HVO. After 1955, typed annotations were no longer placed in the record books, and only photographs, most with captions, were included. Although the volumes titled “Record Book” end with the 1955 volume, the photograph albums that followed are similar, and the record book designation is retained for simplicity. Note that the photographs in these albums were not all originally arranged in chronological order.

Hawaii↗

Hawaiian Volcano Observatory record book 1954

The Hawaiian Volcano Observatory (HVO) record books are annual journals in which field observations of eruptive activity at Kīlauea and Mauna Loa volcanoes, on the Island of Hawaiʻi, were compiled by HVO staff for most years from 1912 through early 1966. In addition to descriptive observations, the record books also contain hundreds of annotated photographs and sketches, as well as temperature and transit measurements. When photographs are included, the camera settings and film types used are noted. The field notes, sketches, and photographs used to compile the record books provide an unparalleled record of eruptive activity and were the basis for published newspaper reports and periodic bulletins, such as the Hawaiian Volcano Observatory bulletins and The volcano letter . HVO staff also painstakingly prepared a second copy of each early record book, virtually identical to the original, complete with photographs and sketches. The original version of the record book was kept at HVO, while the duplicate went to the Hawaiian Volcano Research Association, which was created by a group of Honolulu, Hawaiʻi, businessmen to promote HVO’s work. The Hawaiian Volcano Research Association, which dissolved decades ago, held the duplicate books in Honolulu, where they were more readily accessible to the public. After 1923, HVO stopped duplicating the books—at least, no duplicate records for subsequent years have been found. During the decade of the 1940s, preparation of the record books stopped altogether. In 1952, compilation of the record books resumed and continued, with long gaps, until early 1966. Entries in these later volumes are sparse, and these books are little more than photo albums of the episodic eruptions of Kīlauea. The original record books were held at HVO and, later, at Hawai‘i Volcanoes National Park. In 1972, the original record books for the years 1912 through 1939 were transferred to the Bishop Museum, in Honolulu, for safekeeping. These record books are now stored in archival boxes at that institution (accession number 172.265). The duplicate set of record books held by the Hawaiian Volcano Research Association were bound into volumes at an unknown date and turned over to the U.S. Geological Survey. This set of record books, spanning 1912 through 1923, is now housed in the rare book room of the U.S. Geological Survey Library in Reston, Virginia (catalog number 220(950) H3d). The record books for 1952 through early 1966 remain in storage at HVO. After 1955, typed annotations were no longer placed in the record books, and only photographs, most with captions, were included. Although the volumes titled “Record Book” end with the 1955 volume, the photograph albums that followed are similar, and the record book designation is retained for simplicity. Note that the photographs in these albums were not all originally arranged in chronological order.

Hawaii↗

Hawaiian Volcano Observatory record book 1955

The Hawaiian Volcano Observatory (HVO) record books are annual journals in which field observations of eruptive activity at Kīlauea and Mauna Loa volcanoes, on the Island of Hawaiʻi, were compiled by HVO staff for most years from 1912 through early 1966. In addition to descriptive observations, the record books also contain hundreds of annotated photographs and sketches, as well as temperature and transit measurements. When photographs are included, the camera settings and film types used are noted. The field notes, sketches, and photographs used to compile the record books provide an unparalleled record of eruptive activity and were the basis for published newspaper reports and periodic bulletins, such as the Hawaiian Volcano Observatory bulletins and The volcano letter . HVO staff also painstakingly prepared a second copy of each early record book, virtually identical to the original, complete with photographs and sketches. The original version of the record book was kept at HVO, while the duplicate went to the Hawaiian Volcano Research Association, which was created by a group of Honolulu, Hawaiʻi, businessmen to promote HVO’s work. The Hawaiian Volcano Research Association, which dissolved decades ago, held the duplicate books in Honolulu, where they were more readily accessible to the public. After 1923, HVO stopped duplicating the books—at least, no duplicate records for subsequent years have been found. During the decade of the 1940s, preparation of the record books stopped altogether. In 1952, compilation of the record books resumed and continued, with long gaps, until early 1966. Entries in these later volumes are sparse, and these books are little more than photo albums of the episodic eruptions of Kīlauea. The original record books were held at HVO and, later, at Hawai‘i Volcanoes National Park. In 1972, the original record books for the years 1912 through 1939 were transferred to the Bishop Museum, in Honolulu, for safekeeping. These record books are now stored in archival boxes at that institution (accession number 172.265). The duplicate set of record books held by the Hawaiian Volcano Research Association were bound into volumes at an unknown date and turned over to the U.S. Geological Survey. This set of record books, spanning 1912 through 1923, is now housed in the rare book room of the U.S. Geological Survey Library in Reston, Virginia (catalog number 220(950) H3d). The record books for 1952 through early 1966 remain in storage at HVO. After 1955, typed annotations were no longer placed in the record books, and only photographs, most with captions, were included. Although the volumes titled “Record Book” end with the 1955 volume, the photograph albums that followed are similar, and the record book designation is retained for simplicity. Note that the photographs in these albums were not all originally arranged in chronological order.

Hawaii↗

Hawaiian Volcano Observatory record book 1960, 1965, and 1966

The Hawaiian Volcano Observatory (HVO) record books are annual journals in which field observations of eruptive activity at Kīlauea and Mauna Loa volcanoes, on the Island of Hawaiʻi, were compiled by HVO staff for most years from 1912 through early 1966. In addition to descriptive observations, the record books also contain hundreds of annotated photographs and sketches, as well as temperature and transit measurements. When photographs are included, the camera settings and film types used are noted. The field notes, sketches, and photographs used to compile the record books provide an unparalleled record of eruptive activity and were the basis for published newspaper reports and periodic bulletins, such as the Hawaiian Volcano Observatory bulletins and The volcano letter . HVO staff also painstakingly prepared a second copy of each early record book, virtually identical to the original, complete with photographs and sketches. The original version of the record book was kept at HVO, while the duplicate went to the Hawaiian Volcano Research Association, which was created by a group of Honolulu, Hawaiʻi, businessmen to promote HVO’s work. The Hawaiian Volcano Research Association, which dissolved decades ago, held the duplicate books in Honolulu, where they were more readily accessible to the public. After 1923, HVO stopped duplicating the books—at least, no duplicate records for subsequent years have been found. During the decade of the 1940s, preparation of the record books stopped altogether. In 1952, compilation of the record books resumed and continued, with long gaps, until early 1966. Entries in these later volumes are sparse, and these books are little more than photo albums of the episodic eruptions of Kīlauea. The original record books were held at HVO and, later, at Hawai‘i Volcanoes National Park. In 1972, the original record books for the years 1912 through 1939 were transferred to the Bishop Museum, in Honolulu, for safekeeping. These record books are now stored in archival boxes at that institution (accession number 172.265). The duplicate set of record books held by the Hawaiian Volcano Research Association were bound into volumes at an unknown date and turned over to the U.S. Geological Survey. This set of record books, spanning 1912 through 1923, is now housed in the rare book room of the U.S. Geological Survey Library in Reston, Virginia (catalog number 220(950) H3d). The record books for 1952 through early 1966 remain in storage at HVO. After 1955, typed annotations were no longer placed in the record books, and only photographs, most with captions, were included. Although the volumes titled “Record Book” end with the 1955 volume, the photograph albums that followed are similar, and the record book designation is retained for simplicity. Note that the photographs in these albums were not all originally arranged in chronological order.

Hawaii↗

Hawaiian Volcano Observatory record book 1963

The Hawaiian Volcano Observatory (HVO) record books are annual journals in which field observations of eruptive activity at Kīlauea and Mauna Loa volcanoes, on the Island of Hawaiʻi, were compiled by HVO staff for most years from 1912 through early 1966. In addition to descriptive observations, the record books also contain hundreds of annotated photographs and sketches, as well as temperature and transit measurements. When photographs are included, the camera settings and film types used are noted. The field notes, sketches, and photographs used to compile the record books provide an unparalleled record of eruptive activity and were the basis for published newspaper reports and periodic bulletins, such as the Hawaiian Volcano Observatory bulletins and The volcano letter . HVO staff also painstakingly prepared a second copy of each early record book, virtually identical to the original, complete with photographs and sketches. The original version of the record book was kept at HVO, while the duplicate went to the Hawaiian Volcano Research Association, which was created by a group of Honolulu, Hawaiʻi, businessmen to promote HVO’s work. The Hawaiian Volcano Research Association, which dissolved decades ago, held the duplicate books in Honolulu, where they were more readily accessible to the public. After 1923, HVO stopped duplicating the books—at least, no duplicate records for subsequent years have been found. During the decade of the 1940s, preparation of the record books stopped altogether. In 1952, compilation of the record books resumed and continued, with long gaps, until early 1966. Entries in these later volumes are sparse, and these books are little more than photo albums of the episodic eruptions of Kīlauea. The original record books were held at HVO and, later, at Hawai‘i Volcanoes National Park. In 1972, the original record books for the years 1912 through 1939 were transferred to the Bishop Museum, in Honolulu, for safekeeping. These record books are now stored in archival boxes at that institution (accession number 172.265). The duplicate set of record books held by the Hawaiian Volcano Research Association were bound into volumes at an unknown date and turned over to the U.S. Geological Survey. This set of record books, spanning 1912 through 1923, is now housed in the rare book room of the U.S. Geological Survey Library in Reston, Virginia (catalog number 220(950) H3d). The record books for 1952 through early 1966 remain in storage at HVO. After 1955, typed annotations were no longer placed in the record books, and only photographs, most with captions, were included. Although the volumes titled “Record Book” end with the 1955 volume, the photograph albums that followed are similar, and the record book designation is retained for simplicity. Note that the photographs in these albums were not all originally arranged in chronological order.

Hawaii↗

Hawaiian Volcano Observatory record book 1963, 1964, and 1965

The Hawaiian Volcano Observatory (HVO) record books are annual journals in which field observations of eruptive activity at Kīlauea and Mauna Loa volcanoes, on the Island of Hawaiʻi, were compiled by HVO staff for most years from 1912 through early 1966. In addition to descriptive observations, the record books also contain hundreds of annotated photographs and sketches, as well as temperature and transit measurements. When photographs are included, the camera settings and film types used are noted. The field notes, sketches, and photographs used to compile the record books provide an unparalleled record of eruptive activity and were the basis for published newspaper reports and periodic bulletins, such as the Hawaiian Volcano Observatory bulletins and The volcano letter . HVO staff also painstakingly prepared a second copy of each early record book, virtually identical to the original, complete with photographs and sketches. The original version of the record book was kept at HVO, while the duplicate went to the Hawaiian Volcano Research Association, which was created by a group of Honolulu, Hawaiʻi, businessmen to promote HVO’s work. The Hawaiian Volcano Research Association, which dissolved decades ago, held the duplicate books in Honolulu, where they were more readily accessible to the public. After 1923, HVO stopped duplicating the books—at least, no duplicate records for subsequent years have been found. During the decade of the 1940s, preparation of the record books stopped altogether. In 1952, compilation of the record books resumed and continued, with long gaps, until early 1966. Entries in these later volumes are sparse, and these books are little more than photo albums of the episodic eruptions of Kīlauea. The original record books were held at HVO and, later, at Hawai‘i Volcanoes National Park. In 1972, the original record books for the years 1912 through 1939 were transferred to the Bishop Museum, in Honolulu, for safekeeping. These record books are now stored in archival boxes at that institution (accession number 172.265). The duplicate set of record books held by the Hawaiian Volcano Research Association were bound into volumes at an unknown date and turned over to the U.S. Geological Survey. This set of record books, spanning 1912 through 1923, is now housed in the rare book room of the U.S. Geological Survey Library in Reston, Virginia (catalog number 220(950) H3d). The record books for 1952 through early 1966 remain in storage at HVO. After 1955, typed annotations were no longer placed in the record books, and only photographs, most with captions, were included. Although the volumes titled “Record Book” end with the 1955 volume, the photograph albums that followed are similar, and the record book designation is retained for simplicity. Note that the photographs in these albums were not all originally arranged in chronological order.

Hawaii↗

Hawaiian Volcano Observatory record book 1965

The Hawaiian Volcano Observatory (HVO) record books are annual journals in which field observations of eruptive activity at Kīlauea and Mauna Loa volcanoes, on the Island of Hawaiʻi, were compiled by HVO staff for most years from 1912 through early 1966. In addition to descriptive observations, the record books also contain hundreds of annotated photographs and sketches, as well as temperature and transit measurements. When photographs are included, the camera settings and film types used are noted. The field notes, sketches, and photographs used to compile the record books provide an unparalleled record of eruptive activity and were the basis for published newspaper reports and periodic bulletins, such as the Hawaiian Volcano Observatory bulletins and The volcano letter . HVO staff also painstakingly prepared a second copy of each early record book, virtually identical to the original, complete with photographs and sketches. The original version of the record book was kept at HVO, while the duplicate went to the Hawaiian Volcano Research Association, which was created by a group of Honolulu, Hawaiʻi, businessmen to promote HVO’s work. The Hawaiian Volcano Research Association, which dissolved decades ago, held the duplicate books in Honolulu, where they were more readily accessible to the public. After 1923, HVO stopped duplicating the books—at least, no duplicate records for subsequent years have been found. During the decade of the 1940s, preparation of the record books stopped altogether. In 1952, compilation of the record books resumed and continued, with long gaps, until early 1966. Entries in these later volumes are sparse, and these books are little more than photo albums of the episodic eruptions of Kīlauea. The original record books were held at HVO and, later, at Hawai‘i Volcanoes National Park. In 1972, the original record books for the years 1912 through 1939 were transferred to the Bishop Museum, in Honolulu, for safekeeping. These record books are now stored in archival boxes at that institution (accession number 172.265). The duplicate set of record books held by the Hawaiian Volcano Research Association were bound into volumes at an unknown date and turned over to the U.S. Geological Survey. This set of record books, spanning 1912 through 1923, is now housed in the rare book room of the U.S. Geological Survey Library in Reston, Virginia (catalog number 220(950) H3d). The record books for 1952 through early 1966 remain in storage at HVO. After 1955, typed annotations were no longer placed in the record books, and only photographs, most with captions, were included. Although the volumes titled “Record Book” end with the 1955 volume, the photograph albums that followed are similar, and the record book designation is retained for simplicity. Note that the photographs in these albums were not all originally arranged in chronological order.

Hawaii↗

The 2010 explosive eruption of Java's Merapi volcano—A ‘100-year’ event

Merapi volcano (Indonesia) is one of the most active and hazardous volcanoes in the world. It is known for frequent small to moderate eruptions, pyroclastic flows produced by lava dome collapse, and the large population settled on and around the flanks of the volcano that is at risk. Its usual behavior for the last decades abruptly changed in late October and early November 2010, when the volcano produced its largest and most explosive eruptions in more than a century, displacing at least a third of a million people, and claiming nearly 400 lives. Despite the challenges involved in forecasting this ‘hundred year eruption’, we show that the magnitude of precursory signals (seismicity, ground deformation, gas emissions) was proportional to the large size and intensity of the eruption. In addition and for the first time, near-real-time satellite radar imagery played an equal role with seismic, geodetic, and gas observations in monitoring eruptive activity during a major volcanic crisis. The Indonesian Center of Volcanology and Geological Hazard Mitigation (CVGHM) issued timely forecasts of the magnitude of the eruption phases, saving 10,000–20,000 lives. In addition to reporting on aspects of the crisis management, we report the first synthesis of scientific observations of the eruption. Our monitoring and petrologic data show that the 2010 eruption was fed by rapid ascent of magma from depths ranging from 5 to 30 km. Magma reached the surface with variable gas content resulting in alternating explosive and rapid effusive eruptions, and released a total of ~ 0.44 Tg of SO 2 . The eruptive behavior seems also related to the seismicity along a tectonic fault more than 40 km from the volcano, highlighting both the complex stress pattern of the Merapi region of Java and the role of magmatic pressurization in activating regional faults. We suggest a dynamic triggering of the main explosions on 3 and 4 November by the passing seismic waves generated by regional earthquakes on these days.

Merapi volcano↗

FTIR and py-GC-MS spectra of true-fern and seed-fern sphenopterids (Sydney Coalfield, Nova Scotia, Canada, Pennsylvanian)

Sphenopterid specimens from the Late Pennsylvanian of Sydney Coalfield, Canada, are investigated by FTIR and py-GC-MS techniques as part of an on-going research project into the biochemistry and chemotaxonomy of Pennsylvanian-age pteridophylls. Included in the investigation are samples of the true-fern species Oligocarpia brongniartii and Zeilleria delicatula that are preserved as naturally macerated cuticles (NMC), and the seed-fern Eusphenopteris neuropteroides that is also preserved as a compression/impression. FTIR spectra of NMC seed-fern E. neuropteroides, and fern sphenopterid O. brongniartii are very similar, except that the latter does not have aromatic bands in the 700-900 cm-1 out-of-plane region, py-GC-MS show more aromatic compounds for the seed fern than for the two true-fern sphenopterids. Another difference between seed-fern and true-fern sphenopterids is a lower ratio of CH2 to CH3 in chemically treated specimens (CTC) for the seed fern. These observations suggest slightly higher aromaticity for the seed ferns, perhaps related to some chemotaxonomic differences. Comparison of FTIR and py-GC-MS characteristics of sphenopterids and other plant groups shows that these two techniques have potential to identifying chemotaxonomic signals from Carboniferous pteridophylls in general, although more data are needed to confirm this. ?? 2002 Elsevier Science B.V. All rights reserved.

International Journal of Coal Geology↗

Post-1906 stress recovery of the San Andreas fault system calculated from three-dimensional finite element analysis

The M = 7.8 1906 San Francisco earthquake cast a stress shadow across the San Andreas fault system, inhibiting other large earthquakes for at least 75 years. The duration of the stress shadow is a key question in San Francisco Bay area seismic hazard assessment. This study presents a three-dimensional (3-D) finite element simulation of post-1906 stress recovery. The model reproduces observed geologic slip rates on major strike-slip faults and produces surface velocity vectors comparable to geodetic measurements. Fault stressing rates calculated with the finite element model are evaluated against numbers calculated using deep dislocation slip. In the finite element model, tectonic stressing is distributed throughout the crust and upper mantle, whereas tectonic stressing calculated with dislocations is focused mostly on faults. In addition, the finite element model incorporates postseismic effects such as deep afterslip and viscoelastic relaxation in the upper mantle. More distributed stressing and postseismic effects in the finite element model lead to lower calculated tectonic stressing rates and longer stress shadow durations (17–74 years compared with 7–54 years). All models considered indicate that the 1906 stress shadow was completely erased by tectonic loading no later than 1980. However, the stress shadow still affects present-day earthquake probability. Use of stressing rate parameters calculated with the finite element model yields a 7–12% reduction in 30-year probability caused by the 1906 stress shadow as compared with calculations not incorporating interactions. The aggregate interaction-based probability on selected segments (not including the ruptured San Andreas fault) is 53–70% versus the noninteraction range of 65–77%.

California↗

Field Reconnaissance Geologic Mapping of the Columbia Hills, Mars: Results from MER Spirit and MRO HiRISE Observations

Chemical, mineralogic, and lithologic ground truth was acquired for the first time on Mars in terrain units mapped using orbital Mars Reconnaissance Orbiter's High Resolution Imaging Science Experiment (MRO HiRISE) image data. Examination of several dozen outcrops shows that Mars is geologically complex at meter length scales, the record of its geologic history is well exposed, stratigraphic units may be identified and correlated across significant areas on the ground, and outcrops and geologic relationships between materials may be analyzed with techniques commonly employed in terrestrial field geology. Despite their burial during the course of Martian geologic time by widespread epiclastic materials, mobile fines, and fall deposits, the selective exhumation of deep and well-preserved geologic units has exposed undisturbed outcrops, stratigraphic sections, and structural information much as they are preserved and exposed on Earth. A rich geologic record awaits skilled future field investigators on Mars. The correlation of ground observations and orbital images enables construction of a corresponding geologic reconnaissance map. Most of the outcrops visited are interpreted to be pyroclastic, impactite, and epiclastic deposits overlying an unexposed substrate, probably related to a modified Gusev crater central peak. Fluids have altered chemistry and mineralogy of these protoliths in degrees that vary substantially within the same map unit. Examination of the rocks exposed above and below the major unconformity between the plains lavas and the Columbia Hills directly confirms the general conclusion from remote sensing in previous studies over past years that the early history of Mars was a time of more intense deposition and modification of the surface. Although the availability of fluids and the chemical and mineral activity declined from this early period, significant later volcanism and fluid convection enabled additional, if localized, chemical activity.

Journal of Geophysical Research E: Planets↗

Chronologic and isotopic framework for early Proterozoic crustal evolution in the eastern Mojave Desert region, SE California

The Early Proterozoic geologic evolution of the eastern Mojave Desert region, as defined by characteristics of its supracrustal rocks, granitoids, metamorphism, structural history, and Pb and Nd isotopic signature, contrasts sharply with other Proterozoic provinces of the southwestern United States. The oldest supracrustal rocks of the Mojave Desert region contain zircons over 2.0 Ga, corroborating Nd isotopic evidence for a much older crust here than elsewhere in the southwestern United States. Granitoids widely emplaced within these supracrustal rocks range from 1.76 to 1.64 Ga. The earlier plutons and surrounding supracrustal rocks were metamorphosed to granulite and high amphibolite facies throughout the province at about 1705 Ma in a migmatite-producing event that we term (informally) the Ivanpah orogeny. Subsequent granitoids, emplaced from 1.69 to 1.67 Ga, were voluminous along a north trending belt in the middle of the Mojave province. Younger plutons were emplaced at about 1.66 Ga in several places and at about 1.64 Ga along the extreme southern part of the province. Commonalities between the Proterozoic evolutions of the Mojave and Arizona crustal provinces do not conclusively establish the time that the provinces were juxtaposed; the data only suggest that the juxtaposition occurred between about 1.76 and 1.64 Ga.

Journal of Geophysical Research↗

Fault interaction and stress triggering of twentieth century earthquakes in Mongolia

A cluster of exceptionally large earthquakes in the interior of Asia occurred from 1905 to 1967: the 1905 M7.9 Tsetserleg and M8.4 Bolnai earthquakes, the 1931 M8.0 Fu Yun earthquake, the 1957 M8.1 Gobi-Altai earthquake, and the 1967 M7.1 Mogod earthquake (sequence). Each of the larger (M ??? 8) earthquakes involved strike-slip faulting averaging more than 5 m and rupture lengths of several hundred kilometers. Available geologic data indicate that recurrence intervals on the major source faults are several thousands of years and distances of about 400 km separate the respective rupture areas. We propose that the occurrences of these and many smaller earthquakes are related and controlled to a large extent by stress changes generated by the compounded static deformation of the preceding earthquakes and subsequent viscoelastic relaxation of the lower crust and upper mantle beneath Mongolia. We employ a spherically layered viscoelastic model constrained by the 1994-2002 GPS velocity field in western Mongolia [Vergnolle et al., 2003]. Using the succession of twentieth century earthquakes as sources of deformation, we then analyze the time-dependent change in Coulomb failure stress (????f). At remote interaction distances, static ????f values are small. However, modeled postseismic stress changes typically accumulate to several tenths of a bar over time intervals of decades. Almost all significant twentieth century regional earthquakes (M ??? 6) with well-constrained fault geometry lie in positive ????f lobes of magnitude about +0.5 bar. Our results suggest that significant stress transfer is possible among continental faults separated by hundreds of kilometers and on timescales of decades. Copyright 2003 by the American Geophysical Union.

Journal of Geophysical Research B: Solid Earth↗

East Louisiana continental shelf sediments: a product of delta reworking

Data from 77 vibracores were integrated with 6,700 line-km of high- resolution seismic reflection profiles collected off the eastern Louisiana coast in the region of the St. Bernard Delta, the first of the Holocene highstand deltas of the Mississippi River. Seismic fades and sediment facies were integrated in order to establish the stratigraphic details within this relict delta. Results provide a regional geologic framework from which comparisons can be made with other areas. Holocene deposits in the study area overlie a heavily dissected surface interpreted to represent a lowstand erosional surface. Resting on this surface is a thin unit of relatively clean, quartz sand interpreted to have been deposited during early transgression. This unit is overlain by sediments of the St. Bernard Delta, a seaward-prograding, coarsening-upward wedge of sands and muds that contain vertically-stacked units of deltaic succession. Two or more prograding units separated by an unconformity, delineated from regional seismic profiles, may represent laterally shifting subdelta lobes. Surficial sediments consist of a thin unit of sands and muds derived from and reflecting the individual subenvirons of the underlying delta. Holocene inner-shelf development off eastern Louisiana has been controlled by relative sea-level rise and sediment supply. Sediment supply and deposition are a product of delta progradation and delta-lobe switching. The modern shelf configuration and surficial sediment distribution patterns reflect reworking of underlying deltaic deposits. The lack of modern sediment input helps to maintain the imprint of this ancient delta on the modern shelf surface.

Louisiana↗

Seabird tissue archival and monitoring project: Egg collections and analytical results 1999-2002

In 1998, the U.S. Geological Survey Biological Resources Division (USGS-BRD), the U.S. Fish and Wildlife Service (USFWS) Alaska Maritime National Wildlife Refuge (AMNWR), and the National Institute of Standards and Technology (NIST) began the Seabird Tissue Archival and Monitoring Project (STAMP) to collect and cryogenically bank tissues from seabirds in Alaska for future retrospective analysis of anthropogenic contaminants. The approach of STAMP was similar to that of the Alaska Marine Mammal Tissue Archival Project (AMMTAP). AMMTAP was started in 1987 by NIST and the National Oceanic and Atmospheric Administration (NOAA) as part of the Outer Continental Shelf Environmental Assessment Program sponsored by the Minerals Management Service. Presently sponsored by the USGS-BRD, AMMTAP continues its work as part of a larger national program, the Marine Mammal Health and Stranding Response Program. AMMTAP developed carefully designed sampling and specimen banking protocols. Since 1987, AMMTAP has collected tissues from marine mammals taken in Alaska Native subsistence hunts and has cryogenically banked these tissues at the NIST National Biomonitoring Specimen Bank (NBSB). Through its own analytical work and working in partnership with other researchers both within and outside Alaska, AMMTAP has helped to develop a substantial database on contaminants in Alaska marine mammals. In contrast, data and information is limited on contaminants in Alaska seabirds, which are similar to marine mammals in that they feed near the top of the food chain and have the potential for accumulating anthropogenic contaminants. During its early planning stages, STAMP managers identified the seabird egg as the first tissue of choice for study by the project. There is a relatively long history of using bird eggs for environmental monitoring and for investigating the health status of bird populations. Since 1998, protocols for collecting and processing eggs, and cryogenically banking egg samples have been developed by STAMP (see York et al. 2001). Eggs are being collected on an annual basis for several species at nesting colonies throughout Alaska. Aliquots of these egg samples are being analyzed on a regular basis for persistent organic pollutants and mercury. Results of this work have been published in scientific journals (Christopher et al. 2002) and in conference proceedings (Kucklick et al. 2002; Vander Pol et al. 2002a, 2002b). The intent of this report is to provide an up-to-date description of STAMP. The report contains the most recent egg collection inventory, analytical data, preliminary interpretations based on these data, and a discussion of possible future directions of the project.

Report↗