Abstract Altered pyroclastic (tephra) deposits are highly susceptible to landsliding, leading fatalities and property damage every year. Halloysite, a low-activity clay mineral, is commonly associated with landslide-prone layers within altered tephra successions, especially in high sensitivity, which describes the post-failure strength loss. However, precise role of halloysite development thus sudden unpredictable unknown. Here we show that an abundance mushroom cap–shaped (MCS) spheroidal...

Abstract A combination of a dense reflection seismic grid and up to 50‐m‐long records from sediment cores cone penetration tests was used study the geometry infill lithology an E–W‐trending buried tunnel valley in south‐eastern North Sea. In relation previously known primarily N–S‐trending valleys this area, 38‐km‐long 3‐km‐wide is comparable, but its E–W orientation exceptional. The vertical cross‐section may result subglacial erosion advancing ice streams secondary incision by large...

Using extensive data sets from three separate areas in the German North Sea sector, consisting of seismic grids, cores and in‐situ cone penetration tests (CPT), we have established a revised stratigraphical framework for mid to late Quaternary deposits sector. This consists four regional unconformities 15 other local derived profiles. these unconformities, along with lithological geotechnical data, it was possible define correlate 14 major units 21 subunits within framework. The cover area...

ABSTRACT Coastal seas, and in particular estuarine systems, were significantly affected by Quaternary sea level changes. Furthermore, the dynamics of shelf coastal evolution have had a strong impact on landscapes inhabited humans. The postglacial vast North Sea with its huge drainage e.g. Elbe Paleovalley tributary system, is an excellent research target to understand how environments change response rise. In this study, we investigate infill sediments Paleo‐Ems valley – drowned extension...

Abstract The inundated Doggerland in the North Sea Basin has been a coveted research target for many years owing to its key location with respect geological evolution since last glaciation and archaeological potential related prehistoric hunter–gatherer populations. Still, uncertainties glacial sea-level forcing on erosion deposition remain, first discovery of submerged settlements is yet be reported. In this study, we present range seismic morphologies facies characteristic late Holocene...

Pile setup is not fully understood, despite its high potential for cost saving and risk mitigation in onshore offshore constructions. Studies indicate that the pile installation process has important influence on initial capacity subsequent setup. However, only few studies considered a wide range of methods (e.g., jacking, vibratory driving) when quantifying both characteristics. This study presents data 88 static tension load tests conducted 44 small piles at 1, 2, 10, 100 days after their...

Abstract Variations in the physical properties of water column usually impede exact height correction on high-resolution seismic data, especially when data are collected shallow marine environments. Changes can be attributed to variation tides and currents, wind-generated swells, long short amplitude wave-fronts, or salinity temperature. Likewise, proper motion vessel complicates determinability height. This study provides a less time-consuming precise differential Global Positioning System...

Jorat, M.E.; Moon, V.G.; Hepp, D.A.; Kreiter, S.; de Lange, W.P.; Feldmann, S., and Mörz, T., 2017. Subseafloor investigation of sediments at southern Tauranga Harbour, New Zealand, before capital dredging.The Port plays a key role in Zealand's export–import industry, dredging commenced October 2015 to extend the shipping channels accommodate larger container vessels. This study investigated two-dimensional three-dimensional subsurface estuarine sediment stratigraphy predict sedimentological...

During the Late Pleistocene, Palaeo-Ems system (PES) was one of major tributary channels feeding Elbe Palaeovalley (EPV) and formed an important part drainage continental northwestern Europe unglaciated hinterland. In this study, a detailed interpretation high-resolution 2D sub-bottom profiler Boomer grids were used to map overall course submerged PES channel, as well its spatial stratigraphic relationships with other Quaternary geological units in German North Sea. Mapping buried tunnel...

A detailed stratigraphic and geotechnical investigation of the uppermost 50 m below sea floor was carried out for parts German North Sea sector using combined information from shallow seismic reflection surveys, 50‐m‐long sediment cores cone penetration tests covering an area ~150 km 2 . While most recent studies concentrate on unusual features such as buried tunnel‐ or river‐valleys, this study focused less well understood, regionally dominant sand units deposited after retreat last...

Abstract Understanding of glacially driven sedimentary transport systems across the shelf to slope and subsequently deep sea sediment bodies along Pacific continental margin Antarctic Peninsula is crucial for interpreting ice sheet dynamics. Here we quantify slope-failure frequencies recorded in Pliocene core intervals ODP Site 1095. We used relationship between long-term sedimentation rate marine carbon burial efficiency calculate glacial or interglacial specific rates. Using decompacted...

Summary Laterally heterogeneous and complex near-surface sediment structures in shallow water environments like the North Sea, where Pleistocene sedimentation is influenced by alternating glacial, post-glacial marine processes, require acoustic imaging methods tools optimized for vertical resolution but also geometric settings a broad variety of types. While echosounders are indispensable to image uppermost few metres column soft infill depressions, they quickly come their limits terms...

Seismic facies analysis was performed on approximately 1540 km of 2D high-resolution multi-channel seismic data from the German North Sea. Six were defined in study area. Facies 1 covers Quaternary sand depositional system. 2, 3, and 4 represent three types tunnel-valley infill. These valleys formed during different glacial periods All them are characterized by erosional incision into underlying deposits. 5 probably represents youngest post-glacial sediments after retreat last glacier. 6 is...

The release of meltwater from the margins Late Quaternary Fennoscandian ice sheets resulted in complex networks (now buried) Pleistocene tunnel-valleys that extend beneath large parts North Sea and adjacent northern European lowlands.