Preprints
Filtering by Subject: Physical Sciences and Mathematics
Sub-kilometre scale distribution of snow depth on Arctic sea ice from Soviet drifting stations
Published: 2021-07-23
Subjects: Other Physical Sciences and Mathematics, Physical Sciences and Mathematics
The sub-kilometre scale distribution of snow depth on Arctic sea ice impacts atmosphere-ice fluxes of energy and mass, and is of importance for satellite estimates of sea ice thickness from both radar and lidar altimeters. While information about the mean of this distribution is increasingly available from modelling and remote sensing, the full distribution cannot yet be resolved. We analyse [...]
Conjugate and bending faults drive the multiplex ruptures during the 2014 Mw 6.2 Thailand earthquake
Published: 2021-07-22
Subjects: Earth Sciences, Geology, Geophysics and Seismology, Physical Sciences and Mathematics
A moment magnitude 6.2 crustal earthquake occurred in northern Thailand on 5 May 2014, and its aftershocks exhibit several lineaments with conjugate pattern, involving geometric complexity in a multi-segmented fault system of the Phayao fault zone. However, a relationship between those geometric complexities and the rupture evolution of the 2014 Thailand earthquake is still elusive, which is [...]
Fluvial sedimentation and its reservoir potential at foreland basin margins: A case study of the Puig-reig anticline (South-eastern Pyrenees)
Published: 2021-07-21
Subjects: Earth Sciences, Physical Sciences and Mathematics, Sedimentology
Fluvial fans represent one of the dominant sedimentary systems at the active margins of non-marine foreland basins. The Puig-reig anticline at the north-eastern margin of the Ebro Foreland Basin (SE Pyrenees, Spain) exposes continuous outcrops of late Eocene-early Oligocene fluvial deposits, from proximal to medial fluvial fan environments. The proximal deposits, located in the northern limb of [...]
Geology of a Neogene caldera cluster in Northeast Iceland – clues into rift zone architecture on a young Iceland
Published: 2021-07-18
Subjects: Physical Sciences and Mathematics
The Borgarfjörður-Loðmundarfjörður area in Northeast Iceland hosts an unusual volume of silicic rocks, as well as volcanic and sub-volcanic structures emplaced in the Miocene between 13.5 and 12.2 Ma. Here, we summarise the geology of the area and present a new geological map to summarise the current state of knowledge. We describe the prominent features of the volcanic centres, as well as [...]
Illuminating a Contorted Slab with a Complex Intraslab Rupture Evolution during the 2021 Mw 7.3 East Cape, New Zealand Earthquake
Published: 2021-07-18
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
The state-of-stress within subducting oceanic plates controls rupture processes of deep intraslab earthquakes. However, little is known about how the large-scale plate geometry and the stress regime relate to the physical nature of the deep-intraslab earthquakes. Here we find, by using globally and locally observed seismic records, that the moment magnitude 7.3 2021 East Cape, New Zealand [...]
New systemically measured sand mining budget for the Mekong Delta reveals rising trends and significant volume underestimations
Published: 2021-07-16
Subjects: Civil and Environmental Engineering, Earth Sciences, Physical Sciences and Mathematics, Planetary Sciences
The river beds of the Mekong Delta are some of the most intensively sand mined places in the world, however sand mining budgets are limited to rough and indirect estimates. Here, we provide a systematic, semi-physically based estimation of the Mekong Delta’s sand mining budget. We provide a quantified budget that overcomes limitations resulting from previous reliance on officially declared [...]
Influence of zones of pre-existing crustal weakness on strain localization and partitioning during rifting: Insights from analogue modeling using high resolution 3D digital image correlation
Published: 2021-07-15
Subjects: Earth Sciences, Physical Sciences and Mathematics
The factors controlling the selective reactivation of pre-existing crustal structures and strain localization process in natural rifts have been studied for decades but remain poorly understood. We present the results of surface strain analysis of a series of analogue rifting experiments designed to test the influence of the size, orientation, depth, and geometry of pre-existing crustal weak [...]
Noise in the Cretaceous Quiet Zone uncovers plate tectonic chain reaction
Published: 2021-07-13
Subjects: Education, Physical Sciences and Mathematics
Global plate reorganizations, intriguing but loosely defined periods of profoundly changing plate motions, may be caused by a single trigger such as a continental collision or a rising mantle plume. But whether and how such triggers propagate throughout a plate circuit remains unknown. Here, we show how a rising mantle plume set off a ‘plate tectonic chain reaction’. Plume rise has been shown to [...]
Multivariate statistical appraisal of regional susceptibility to induced seismicity: application to the Permian Basin, SW United States
Published: 2021-07-13
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Induced earthquake sequences are typically interpreted through causal triggering mechanisms. However, studies of causality rarely consider large regions and why some regions experiencing similar anthropogenic activities remain largely aseismic. Therefore, it can be difficult to forecast seismic hazard at a regional scale. In contrast, multivariate statistical methods allow us to find the [...]
The effect of lateral variations in Earth structure on Last Interglacial sea level
Published: 2021-07-12
Subjects: Physical Sciences and Mathematics
It is generally agreed that the Last Interglacial (LIG; 130 – 115 ka)was a time when global average temperatures and global mean sea level were higher than they are today. However, the exact timing, magnitude, and spatial pattern of ice melt is much debated. One difficulty in extracting past global mean sea level from local observations is that their elevations need to be corrected for glacial [...]
Energetics and mixing of stratified, rotating flow over abyssal hills
Published: 2021-07-12
Subjects: Earth Sciences, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
One of the proposed mechanisms for energy loss in the ocean is through dissipation of internal waves, in particular above rough topography where internal lee waves are generated. Rates of dissipation and diapycnal mixing are often estimated using linear theory and a constant value for mixing efficiency. However, previous oceanographic measurements found that non-linear dynamics may be important [...]
A convolutional neural network approach to estimate earthquake kinematic parameters from back-projection images
Published: 2021-07-09
Subjects: Physical Sciences and Mathematics
The retrieval of earthquake finite-fault kinematic parameters after the occurrence of an earthquake is a crucial task in observational seismology. Routinely-used source inversion techniques are challenged by limited data coverage and computational effort, and are subject to a variety of assumptions and constraints that restrict the range of possible solutions. Back-projection (BP) imaging [...]
The origin and 3D architecture of a km-scale deep-water scour-fill: example from the Skoorsteenberg Fm., Karoo Basin, South Africa
Published: 2021-07-08
Subjects: Physical Sciences and Mathematics
Scours, and scour fields, are common features on the modern seafloor of deep-marine systems, particularly downstream of submarine channels, and in channel-lobe-transitions-zones. High-resolution images of the seafloor have improved the documentation of the large scale, coalescence, and distribution of these scours in deep-marine systems. However, their scale and high aspect ratio mean they can be [...]
Impact of igneous intrusion and associated ground deformation on the stratigraphic record
Published: 2021-07-08
Subjects: Physical Sciences and Mathematics
The geomorphology and sediment systems of volcanic areas can be influenced by uplift (forced folding) related to subsurface migration and accumulation of magma. Seismic geomorphological analysis presents a unique tool to study how surface morphology and subsurface magma dynamics relate, given seismic reflection data can image buried landscapes and underlying intrusions in 3D at resolutions of [...]
Channel incision into a submarine landslide: an exhumed Carboniferous example from the Paganzo Basin, San Juan, Argentina
Published: 2021-07-08
Subjects: Physical Sciences and Mathematics
Emplacement of submarine landslides, or mass transport deposits, can radically reshape the physiography of continental margins, and strongly influence subsequent sedimentary processes and dispersal patterns. The irregular relief they generate creates obstacles that force reorganisation of sediment transport systems. Subsurface and seabed examples show that channels can incise directly into [...]