Report for borehole explosion data acquired in the 1999 Los Angeles Region Seismic Experiment (LARSE II), Southern California: Part I, description of the survey
Why is this work in the frame?
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Full frame distilled prediction
Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
- Candidate categories
- none
- Consensus categories
- none
- Domain
- Candidate signal: noneConsensus signal: none
- Study design
- Candidate signal: ObservationalConsensus signal: Observational
- Genre
- Candidate signal: EmpiricalConsensus signal: Empirical
- Teacher disagreement score
- 0.142
- Threshold uncertainty score
- 0.992
- Validation status
machine_predicted_unvalidated·codex-gemma-dda1882f352a
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.002 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
- Teacher spread
- 0.178 · how far apart the two teachers sit on this one work
- Validation status
score_only:v0-immature-baseline· verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it
Abstract
The Los Angeles Region Seismic Experiment (LARSE) is a joint project of the U.S. Geological Survey (USGS) and the Southern California Earthquake Center (SCEC). The purpose of this project is to produce seismic images of the subsurface of the Los Angeles region down to the depths at which earthquakes occur, and deeper, in order to remedy a deficit in our knowledge of the deep structure of this region. This deficit in knowledge has persisted despite over a century of oil exploration and nearly 70 years of recording earthquakes in southern California. Understanding the deep crustal structure and tectonics of southern California is important to earthquake hazard assessment. Specific imaging targets of LARSE include (a) faults, especially blind thrust faults, which cannot be reliably detected any other way; and (b) the depths and configurations of sedimentary basins. Imaging of faults is important in both earthquake hazard assessment but also in modeling earthquake occurrence. Earthquake occurrence cannot be understood unless the earthquake-producing "machinery" (tectonics) is known (Fuis and others, 2001). Imaging the depths and configurations of sedimentary basins is important because earthquake shaking at the surface is enhanced by basin depth and by the presence of sharp basin edges (Wald and Graves, 1998, Working Group on California Earthquake Probabilities, 1995; Field and others, 2001). (Sedimentary basins are large former valleys now filled with sediment eroded from nearby mountains.) Sedimentary basins in the Los Angeles region that have been investigated by LARSE include the Los Angeles, San Gabriel Valley, San Fernando Valley, and Santa Clarita Valley basins. The seismic imaging surveys of LARSE include recording of earthquakes (both local and distant earthquakes) along several corridors (or transects) through the Los Angeles region and also recording of man-made sources along these same corridors. Man-made sources have included airguns offshore and borehole explosions and vibrating-truck sources onshore. The two chief LARSE transects pass near recent moderate earthquakes, including the 1971 M 6.7 San Fernando, 1987 M 5.9 Whittier Narrows, 1991 M 5.8 Sierra Madre, and 1994 M 6.7 Northridge earthquakes. The first transect extended from San Clemente Island northeastward to the Mojave Desert (Line 1, Fig. 1), passing near the epicenter of the Whittier Narrows and Sierra Madre earthquakes. The second transect extended from west of San Clemente Island northward to the western Mojave Desert (Line 2, Figs. 1, 2), passing through the epicenter of the Northridge earthquake and near the epicenter of the San Fernando earthquake. Data along Line 1 were acquired during the years 1993-1994, and data along Line 2, during the years 1994–2000. In this open-file report and that of Murphy and others (in preparation), we present the details of the October 1999 explosion survey along Line 2, which extended from Santa Monica Bay northward to the western Mojave Desert (Figs. 1, 2). This survey is referred to as LARSE II. In this survey, 93 borehole explosions were detonated along the main north-south line and along 5 auxiliary lines in the San Fernando Valley and Santa Monica areas. These explosions were recorded by ~1400 seismographs. A variety of seismic instrumentation was used in these imaging surveys and was obtained from collaborators from around the world, including the Geological Survey of Canada (Ottawa, Canada), IRIS/PASSCAL (Socorro, NM), Lamont-Doherty Earth Observatory (Palisades, NY), Stanford University (Stanford, CA), SCEC (Los Angeles, CA), USGS (Menlo Park, CA, and Woods Hole, MA), University of Texas at El Paso (El Paso, TX), GeoForschungsZentrum (Potsdam, Germany), University of Karlsruhe (Karlsruhe, Germany), and University of Copenhagen (Copenhagen, Denmark). The reader is referred to Table 1 for instrumentation used in LARSE II.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
The record
- Venue
- Antarctica A Keystone in a Changing World
- Topic
- earthquake and tectonic studies
- Field
- Earth and Planetary Sciences
- Canadian institutions
- Geological Survey of Canada
- Funders
- U.S. Forest ServiceCalifornia Department of Parks and RecreationCalifornia State University, NorthridgeSouthern California Gas CompanyAustralian Government
- Keywords
- GeologySeismologySedimentary basinStructural basinTectonicsSeismic hazardGeological surveyBoreholeThrust faultSedimentary rockPaleoseismologyFault (geology)GeomorphologyPaleontology
- Has abstract in OpenAlex
- yes