Accretionary lapilli from the Sudbury impact event

Abstract Pelvic fractures are relatively uncommon, and in workers’ compensation most pelvic fractures are the result of an acute, high-impact event such as a fall from a roof or an automobile collision. A person with osteoporosis may sustain a pelvic fracture from a lower-impact injury such as a minor fall. Further, major parts of the bladder, bowel, reproductive organs, nerves, and blood vessels pass through the pelvic ring, and traumatic pelvic fractures that result from a high-impact event often coincide with damaged organs, significant bleeding, and sensory and motor dysfunction. Following are the steps in the rating process: 1) assign the diagnosis and impairment class for the pelvis; 2) assign the functional history, physical examination, and clinical studies grade modifiers; and 3) apply the net adjustment formula. Because pelvic fractures are so uncommon, raters may be less familiar with the rating process for these types of injuries. The diagnosis-based methodology for rating pelvic fractures is consistent with the process used to rate other musculoskeletal impairments. Evaluators must base the rating on reliable data when the patient is at maximum medical impairment and must assess possible impairment from concomitant injuries.

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Chicxulub impact event; computer animations and paper models

Open-File Report ◽

10.3133/ofr97442b ◽

1997 ◽

Author(s):

T.R. Alpha ◽

J.P. Galloway ◽

S.W. Starratt

Keyword(s):

Impact Event ◽

Computer Animations ◽

Chicxulub Impact

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Chicxulub impact event; computer animations and paper models

Open-File Report ◽

10.3133/ofr97442a ◽

1997 ◽

Author(s):

T.R. Alpha ◽

John P. Galloway ◽

S.W. Starratt

Keyword(s):

Impact Event ◽

Computer Animations ◽

Chicxulub Impact

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Seismite in the Devonian Sultan Formation, Frenchman Mountain, Nevada: Evidence of far-field effect of the Alamo Event

The Mountain Geologist ◽

10.31582/rmag.mg.53.2.93 ◽

2016 ◽

Vol 53 (2) ◽

pp. 93-114

Author(s):

Jesús Pinto ◽

John Warme

Keyword(s):

Carbonate Platform ◽

Far Field ◽

Carbonate Sediments ◽

Impact Event ◽

Complex Matrix ◽

Near Surface ◽

Fault Block ◽

Southern Nevada ◽

Salt Pan ◽

The Alamo

We interpret a discrete, anomalous ~10-m-thick interval of the shallow-marine Middle to Late Devonian Valentine Member of the Sultan Formation at Frenchman Mountain, southern Nevada, to be a seismite, and that it was generated by the Alamo Impact Event. A suite of deformation structures characterize this unique interval of peritidal carbonate facies at the top of the Valentine Member; no other similar intervals have been discovered in the carbonate beds on Frenchman Mountain or in equivalent Devonian beds exposed in ranges of southern Nevada. The disrupted band extends for 5 km along the Mountain, and onto the adjoining Sunrise Mountain fault block for an additional 4+km. The interval displays a range of brittle, ductile and fluidized structures, and is divided into four informal bed-parallel units based on discrete deformation style and internal features that carry laterally across the study area. Their development is interpreted as the result of intrastratal compressional and contractional forces imposed upon the unconsolidated to fully cemented near-surface carbonate sediments at the top of the Valentine Member. The result is an assemblage of fractured, faulted, and brecciated beds, some of which were dilated, fluidized and injected to form new and complex matrix bands between beds. We interpret that the interval is an unusually thick and well displayed seismite. Because the Sultan Formation correlates northward to the Frasnian (lower Upper Devonian) carbonate rocks of the Guilmette Formation, and the Guilmette contains much thicker and more proximal exposures of the Alamo Impact Breccia, including seismites, we interpret the Frenchman Mountain seismite to be a far-field product of the Alamo Impact Event. Accompanying ground motion and deformation of the inner reaches of the Devonian carbonate platform may have resulted in a fall of relative sea level and abrupt shift to a salt-pan paleoenvironment exhibited by the post-event basal beds of the directly overlying Crystal Pass Member.

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Extreme shearography: Development of a high-speed shearography instrument for quantitative surface strain measurements during an impact event

Optics and Lasers in Engineering ◽

10.1016/j.optlaseng.2020.106502 ◽

2021 ◽

Vol 140 ◽

pp. 106502

Author(s):

Andrei G. Anisimov ◽

Roger M. Groves

Keyword(s):

High Speed ◽

Surface Strain ◽

Impact Event ◽

Strain Measurements

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Observations of Comet 9P/Tempel 1 around the Deep Impact event by the OSIRIS cameras onboard Rosetta

Icarus ◽

10.1016/j.icarus.2006.09.023 ◽

2007 ◽

Vol 187 (1) ◽

pp. 87-103 ◽

Cited By ~ 22

Author(s):

Horst Uwe Keller ◽

Michael Küppers ◽

Sonia Fornasier ◽

Pedro J. Gutiérrez ◽

Stubbe F. Hviid ◽

...

Keyword(s):

Impact Event ◽

Deep Impact

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An unusual occurrence of mafic accretionary lapilli in deep-marine volcaniclastics on 'Eua, Tonga: Palaeoenvironment and process

Journal of Volcanology and Geothermal Research ◽

10.1016/j.jvolgeores.2014.01.012 ◽

2014 ◽

Vol 274 ◽

pp. 139-151 ◽

Cited By ~ 3

Author(s):

J.K. Cunningham ◽

A.D. Beard

Keyword(s):

Accretionary Lapilli ◽

Unusual Occurrence

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Outflow ignimbrite sheets from Late Carboniferous calderas, Currabubula Formation, New South Wales, Australia

Geological Magazine ◽

10.1017/s0016756800027485 ◽

1983 ◽

Vol 120 (5) ◽

pp. 487-503 ◽

Cited By ~ 21

Author(s):

J. McPhie

Keyword(s):

New South ◽

Sedimentary Facies ◽

Late Carboniferous ◽

The West ◽

Pyroclastic Deposits ◽

Flow Units ◽

South Wales ◽

Accretionary Lapilli ◽

North Eastern ◽

Thickness Variations

SummaryRegionally mappable, silicic, outflow ignimbrite sheets are interbedded with fluvial volcanogenic conglomerates and sandstones of the Late Carboniferous Currabubula Formation of north-eastern N.S.W. Four of the most widespread of these ignimbrites are described and defined as members. The oldest member is comprised of many thin, originally non-welded flow units. Interbedded accretionary lapilli horizons may indicate phreatomagmatic activity at vent during the eruption in addition to local rain-flushing of co-ignimbrite ash clouds. Of the three other members, two are multiple flow-unit sheets, 160–180 m in aggregate thickness. Substantial portions of these sheets were originally welded. The remaining member is a simple welded ignimbrite characterized by abundant spherulites and lithophysae. Irregular pre-eruption topography and contemporaneous erosion were responsible for thickness variations of the ignimbrite sheets. Some palaeovalleys, now delineated by the ignimbrites, persisted in spite of repeated pyroclastic influxes. Relic pumice, shards and crystal fragments are ubiquitous components of the sedimentary facies of the Currabubula Formation, and were probably derived from originally poorly consolidated pyroclastic deposits such as airfall ash layers and non-welded ignimbrites. No surface trace of the sources of these ignimbrites exists. However, internal facies, thickness variations and volumes of the ignimbrites indicate that they periodically emanated from a multiple-caldera terrain which was continuously active during the Late Carboniferous, and located several kilometres to the west of present exposures.

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