Thermal structure of the southern Apennines along the Val d'Agri-Bari transect

Abstract Four one-dimensional models which have been used to characterize surface mixed layer (ML) processes and the thermal structure are described. Although most any model can be calibrated to mimic surface water temperatures, it does not imply that the corresponding mixing processes are well described. Eddy diffusion or "K" models can exhibit this problem. If a ML model is to be useful for water quality applications, then it must be able to resolve storm events and, therefore, be able to simulate the ML depth, h, and its time rate of change, dh/dt. A general water quality model is derived from mass conservation principles to demonstrate how ML models can be used in a physically meaningful way to address water quality issues.

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INVESTIGATING THE SEISMIC AND THERMAL STRUCTURE OF THE CIRCUM-ARCTIC LITHOSPHERE AND ASTHENOSPHERE

10.1130/abs/2017am-294988 ◽

2017 ◽

Author(s):

Andrew J. Schaeffer ◽

◽

Sergei Lebedev ◽

Javier Fullea ◽

Pascal Audet

Keyword(s):

Thermal Structure

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THE COMPOSITIONAL AND THERMAL STRUCTURE OF THE LITHOSPHERE AND UPPER MANTLE BENEATH THE SUPERIOR CRATON: RESULTS FROM MULTI-OBSERVABLE PROBABILISTIC INVERSION

10.1130/abs/2020am-353031 ◽

2020 ◽

Author(s):

Riddhi Dave ◽

◽

Fiona Darbyshire ◽

Juan Carlos Afonso ◽

Khaled Ali

Keyword(s):

Upper Mantle ◽

Thermal Structure ◽

Superior Craton ◽

Probabilistic Inversion

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Thermal squeezing of the seismogenic zone controlled rupture of the volcano-rooted Flores Thrust

Science Advances ◽

10.1126/sciadv.abe2348 ◽

2021 ◽

Vol 7 (5) ◽

pp. eabe2348

Author(s):

Karen Lythgoe ◽

Muzli Muzli ◽

Kyle Bradley ◽

Teng Wang ◽

Andri Dian Nugraha ◽

...

Keyword(s):

Thermal Structure ◽

Critical Role ◽

Volcanic Edifice ◽

Seismic Array ◽

Temperature Gradients ◽

Seismogenic Zone ◽

Arc Volcano

Temperature plays a critical role in defining the seismogenic zone, the area of the crust where earthquakes most commonly occur; however, thermal controls on fault ruptures are rarely observed directly. We used a rapidly deployed seismic array to monitor an unusual earthquake cascade in 2018 at Lombok, Indonesia, during which two magnitude 6.9 earthquakes with surprisingly different rupture characteristics nucleated beneath an active arc volcano. The thermal imprint of the volcano on the fault elevated the base of the seismogenic zone beneath the volcanic edifice by 8 km, while also reducing its width. This thermal “squeezing” directly controlled the location, directivity, dynamics, and magnitude of the earthquake cascade. Earthquake segmentation due to thermal structure can occur where strong temperature gradients exist on a fault.

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Urca nuclide production in Type-I X-ray bursts and implications for nuclear physics studies

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa3414 ◽

2020 ◽

Vol 500 (3) ◽

pp. 2958-2968

Author(s):

Grant Merz ◽

Zach Meisel

Keyword(s):

Light Curve ◽

Nuclear Reaction ◽

Nuclear Physics ◽

Thermal Structure ◽

Reaction Rates ◽

High Mass ◽

Type I ◽

Model Calculations ◽

X Ray ◽

Lower Temperature

ABSTRACT The thermal structure of accreting neutron stars is affected by the presence of urca nuclei in the neutron star crust. Nuclear isobars harbouring urca nuclides can be produced in the ashes of Type I X-ray bursts, but the details of their production have not yet been explored. Using the code MESA, we investigate urca nuclide production in a one-dimensional model of Type I X-ray bursts using astrophysical conditions thought to resemble the source GS 1826-24. We find that high-mass (A ≥ 55) urca nuclei are primarily produced late in the X-ray burst, during hydrogen-burning freeze-out that corresponds to the tail of the burst light curve. The ∼0.4–0.6 GK temperature relevant for the nucleosynthesis of these urca nuclides is much lower than the ∼1 GK temperature most relevant for X-ray burst light curve impacts by nuclear reaction rates involving high-mass nuclides. The latter temperature is often assumed for nuclear physics studies. Therefore, our findings alter the excitation energy range of interest in compound nuclei for nuclear physics studies of urca nuclide production. We demonstrate that for some cases this will need to be considered in planning for nuclear physics experiments. Additionally, we show that the lower temperature range for urca nuclide production explains why variations of some nuclear reaction rates in model calculations impacts the burst light curve but not local features of the burst ashes.

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Stratigraphic and Tectonic Setting of the Liguride Units Cropping Out along the Southeastern Side of the Agri Valley (Southern Apennines, Italy)

Geosciences ◽

10.3390/geosciences11030125 ◽

2021 ◽

Vol 11 (3) ◽

pp. 125

Author(s):

Giacomo Prosser ◽

Giuseppe Palladino ◽

Dario Avagliano ◽

Francesco Coraggio ◽

Eleonora Maria Bolla ◽

...

Keyword(s):

Field Survey ◽

Southern Italy ◽

Tectonic Setting ◽

Mediterranean Area ◽

Fold Belt ◽

Southern Apennines ◽

Tectonic Structures ◽

Subsurface Geology ◽

Multidisciplinary Study ◽

Geological Map

This paper shows the main results of a multidisciplinary study performed along the southeastern sector of the Agri Valley in Basilicata (Southern Italy), where Cenozoic units, crucial for constraining the progressive evolution of the Southern Apennine thrust and fold belt and, more in general, the geodynamic evolution of the Mediterranean area are widely exposed. In particular, we aimed at understanding the stratigraphic and tectonic setting of deep-sea, thrust-top Cenozoic units exposed immediately to north of Montemurro, between Costa Molina and Monte dell’Agresto. In the previous works different units, showing similar sedimentological characteristics but uncertain age attribution, have been reported in the study area. In our study, we focussed on the Albidona Formation, pertaining to the Liguride realm, which shows most significant uncertainties regarding the age and the stratigraphic setting. The study was based on a detailed field survey which led to a new geological map of the area. This was supported by new stratigraphic, biostratigraphic and structural analyses. Biostratigraphic analysis provided an age not older than the upper Ypresian and not younger than the early Priabonian. Recognition of marker stratigraphic horizons strongly helped in the understanding of the stratigraphy of the area. The study allowed a complete revision of the stratigraphy of the outcropping Cenozoic units, the recognition of until now unknown tectonic structures and the correlation between surface and subsurface geology.

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