Antineutrinos produced at nuclear reactors constitute a severe source of background for the detection of geoneutrinos, which bring to the Earth’s surface information about natural radioactivity in the whole planet. In this framework, we provide a reference worldwide model for antineutrinos from reactors, in view of reactors operational records yearly published by the International Atomic Energy Agency. We evaluate the expected signal from commercial reactors for ongoing (KamLAND and Borexino), planned ($\mathrm{SNO}+$), and proposed (Juno, RENO-50, LENA, and Hanohano) experimental sites. Uncertainties related to reactor antineutrino production, propagation, and detection processes are estimated using a Monte Carlo-based approach, which provides an overall site-dependent uncertainty on the signal in the geoneutrino energy window on the order of 3%. We also implement the off-equilibrium correction to the reference reactor spectra associated with the long-lived isotopes, and we estimate a 2.4% increase of the unoscillated event rate in the geoneutrino energy window due to the storage of spent nuclear fuels in the cooling pools. We predict that the research reactors contribute to less than 0.2% to the commercial reactor signal in the investigated 14 sites. We perform a multitemporal analysis of the expected reactor signal over a time lapse of ten years using reactor operational records collected in a comprehensive database published at www.fe.infn.it/antineutrino.

The Semail Gap/Semail Gap Fault Zone is one of the most prominent tectonic features in the Oman Mountains and is located between the Jabal Akhdar Dome in the west and the Saih Hatat Dome to the east. The two domes were uplifted during the Late Eocene to Early Miocene. Uplift led to monoclinal bending with a “fold axis” parallel to the Semail Gap. Subsequently, dextral transtensional faulting along the Semail Gap Fault Zone ensued. This fault zone follows a major preexisting fault, which explains the distribution differences of Neoproterozoic and Phanerozoic sedimentary formations (partly omissions) across this structure. The vertical and horizontal displacements along the Semail Gap amount to up to ~5.5 and ≤2 km, respectively. Vertical displacement may be a combination of monoclinal bending and later faulting along the Semail Gap Fault Zone. Its latest activity mainly preceded the Quaternary because there is only minor faulting of Quaternary deposits. Despite ongoing uplift of the Oman Mountains, which may amount to ≤50 m during the Quaternary based on incision of wadi/alluvial terraces, only insignificant seismicity is observed and attributed to minor movements along this fault zone. The transtensional deformation is a result of uplift and orogenic/gravitational collapse of the Jabal Akhdar/Saih Hatat domes. The neighboring two hanging wall blocks of each dome moved downward, ESE/SE and SSW/SW, which explains dextral transtension along the Semail Gap Fault Zone. The Semail Gap Fault Zone has a sinistral transtensional counterpart at the southwestern margin of the Nakhl Subdome/Saih Hatat Dome.