Jens Hornung

Technische Universität Darmstadt | TU · Institute of Applied Geosciences

The sedimentary architecture of an alpine alluvial fan with a surface of 300,000m2 near Samedan, Switzerland, was three-dimensionally investigated using 9km of ground penetrating radar sections with a penetration depth of 10m. Radar facies patterns could be very well calibrated to sedimentology and dated horizons due to a 300m long outcrop section...

Tertiary-Holocene continental volcanic sediments in southern Guatemala were deposited in three basins each approximately 150 km long and 50 to 100 km wide. Boundaries between these basins mark the positions of transverse breaks in the underlying lithospheric slab. The rates of sediment accumulation and subsidence, and the composition, texture, and...

Permeability is one of the most important petrophysical parameters to describe the reservoir properties of sedimentary rocks, pertaining to problems in hydrology, geothermics, and hydrocarbon reservoir analysis. Outcrop analogue studies, well core measurements, and individual sample analysis take advantage of a variety of commercially available dev...

The publication at hand are the proceedings of the 15th International Conference on Archaeological Prospection held between March 28 and April 1, 2023, in Kiel, Germany. The content of the articles ranges from local to large-scale case studies all over the world and from various archaeological times, over methodological improvements, new processing...

Knowledge about the initial tectonic and depositional dynamics, as well as the influence of early rifting on climate and environmental evolution remains speculative to a large extent, because sediments are usually deeply buried. Within the East African Rift System, inversion tectonics uplifted a few of these successions to the surface hence present...

The sampling of fluvial sediment is subject to many sources of uncertainty, for example, time and location, and the number of samples collected. It is nevertheless commonly assumed that a sample taken at one time and location provides a somewhat averaged compositional signal. Any spatial or temporal variability of this signal is often neglected. Th...

Weathering is a basic geological process that refers to the breaking down or dissolving of rocks and minerals on the surface of the earth. However, weathering characteristics may vary among different lithologies even under similar conditions. To evaluate and quantitatively compare the physical and chemical index of alteration among different types...

Generally, it is assumed that deposition of aeolian sands in the northern Upper Rhine Graben (URG) occurred in multiple phases during the Würm glaciation with the main period linked to the Younger Dryas. But the age of the aeolian sands was mainly based on stratigraphic evidence and its location relative to the Rhine and Neckar rivers. Moreover, pr...

Outsize fans are characterized by seemingly disproportionately small feeder catchments in relation to their fan area. Often having escaped rigorous scientific inquiry, the formative processes of these landforms remain inconclusive, supposedly ranging from catastrophic mass-wasting processes to gradual fluvial formation. Here we apply a multi-method...

The ecogroup classification based on the growth-form of plants (Eco-Plant model) is widely used for extant, Cenozoic, Mesozoic, and Paleozoic paleoenvironmental reconstructions. However, for most Mesozoic dispersed sporomorphs, the application of the Eco-Plant model is limited because either their assignment to a specific ecogroup remains uncertain...

In 2015, some 170 stone concentrations came to light during depth surveying undertaken in Lake Constance. The flat mounds of pebbles were found arranged in a row like beads on a string along the shallow water zone at the southern end of Lake Constance between Romanshorn and Altnau, some 200 to 300 m from the lakeshore at a depth of 3 to 5 metres. S...

Appendix 1 PHP code for the user interface

Appendix 2 PHP and MySQL codes for different modes processing the uploaded dataset.

Patterns of community assemblage for plants are associated with particular climatic elements such as water, heat, light, and air. The classification based on these plant assemblages is referred to here as the ecogroup of plants (Eco-Plant), whereas the method of analysing palaeoenvironmental and palaeoclimate variation by using Eco-Plant is called...

Subsurface characterization is an interdisciplinary and multidimensional problem requiring contribution from numerous geoscientific and technical domains. In order to optimize and automate the process of subsurface characterization and structural modeling we developed a modular, open-source software system called GeoReVi (Geological Reservoir Virtu...

The Cenozoic Kalahari Basin covers large parts of southern Africa. A continuous 400 m core was obtained in northern Namibia and analyzed in detail. Here, we present sedimentological, geochemical, mineralogical, granulometric, and hydraulic data, which were used to derive the sedimentation history and the Cenozoic paleoclimate and paleogeography of...

The prediction of physicochemical rock properties in subsurface models regularly suffers from uncertainty observed at the submeter scale. Although at this scale – which is commonly termed the lithofacies scale – the physicochemical variability plays a critical role for various types of subsurface utilization, its dependence on syndepositional and p...

Terrestrial deposits of the Triassic-Jurassic transition are well developed in the Junggar Basin, located in the Haojiagou Valley of Urumqi, Xinjiang Uygur Autonomous Region of Northwest China. This paper describes the palynology of a 10 m thick lignite bed from the Upper Triassic Haojiagou Formation (Rhaetian) with the aim of reconstructing the pa...

Quantitative lithofacies characterization and prediction of reservoir properties is challenging on the scale of individual grid blocks (voxels) of geocellular models. To better understand variability of petrophysical properties on this scale, this study links geological features and petrophysical properties based on high-resolution characterization...

Abstract. The prediction of physicochemical rock properties in subsurface models regularly suffers from uncertainty observed at the sub-meter scale. Although at this scale – which is commonly termed the lithofacies scale – the physicochemical variability plays a critical role for various types of subsurface utilization, its dependence on syn- and p...

In recent years, outcrop analogue studies have become a powerful tool in sedimentology for the assessment of reservoirs, both in hydrocarbon and aquifer studies. Data from exploratory drilling campaigns can be augmented significantly by observations on the outcrop of the stratigraphical interval with the objective to validate the borehole informat...

In recent years, outcrop analogue studies have become a powerful tool in sedimentology for the assessment of reservoirs, both in hydrocarbon and aquifer studies. Data from exploratory drilling campaigns can be augmented significantly by observations on the outcrop of the stratigraphical interval with the objective to validate the borehole informati...

Dieses Kapitel zeigt die ersten Messergebnisse eines Unterwassergeoradars. Es wurde entwickelt, um die Stratigraphie von Oberflächensedimenten in der Flachwasserzone zu erkunden, in denen hydroakustische Verfahren in der Regel scheitern. Die ersten Erfahrungen in Untersuchungsgebieten des HyMoBioStrategie-Projekts zeigen das hohe Potential dieser T...

Alluvial fans record climate-driven erosion and sediment-transport processes and allow reconstructing past environmental conditions. Here we investigate the sedimentation history of two alluvial fans located in formerly glaciated valleys of the Cordillera Oriental, Peru. ¹⁰ Be exposure ages from the fan surfaces and radiocarbon ages from the fan in...

Dielectric permittivity is a fundamental parameter for all investigations based on electromagnetic waves, particularly for moisture sounding. However, the physical principles of dielectric permittivity in natural materials and its influence on propagation velocity, the reflection coefficient, and the decay of the electromagnetic waves have been rar...

Rift sediments are important archives for the evolution of the East African Rift System. We present a source-to-sink study of the Nkondo-Kaiso area in the northern Albertine Rift from a ∼200 m thick late Miocene to early Pleistocene sediment succession. The multi-proxy provenance analysis include framework petrography, heavy mineral studies and sin...

Bei polizeilichen Suchmaßnahmen müssen oft größere Erd­arbeiten durchgeführt oder gar Bauwerksteile aufgerissen werden. Dies ist mit hohem Zeit- und Kostenaufwand ver­bunden. Georadar kann Anhaltspunkte für die Lage des Zielobjekts liefern, so lassen sich solche Maßnahmen in ihrem Ausmaß einschränken oder gar vermeiden. Im Rahmen einer Studie zum f...

Miocene to Pleistocene synrift sediments in the Albertine Graben reflect the complex geodynamic evolution in the Western branch of the East African Rift System. In this study we focus on the provenance of these siliciclastic deposits to identify sediment sources and supply paths with the ultimate goal to reconstruct the exhumation history of differ...

In hot-humid equatorial climate chemical weathering may be so strong that provenance signatures may be largely lost and even detritus derived from crystalline basement rocks reduced to quartzose sand. We tested this hypothesis in western Uganda, where stable plateau areas contrast with the active tectonic setting of the Albertine Rift (western bran...

Filtering and storage of precipitation, runoff, and subsequent groundwater recharge is governed by the structure and properties of the shallow subsurface and the soils formed therein. Hence, detailed knowledge about the three-dimensional structure, thickness and composition of the shallow subsurface is essential to quantify these processes; special...

Alluvial fans serve as useful archives that record the history of depositional and erosional processes in mountainous regions and thus can reveal the environmental controls that influenced their development. Economically they play an important role as groundwater reservoirs as well as host rocks for hydrocarbons in deeply buried systems. The interp...

Sandstones are often characterized as fractured aquifers. We present a case study of the Wajid sandstone, which forms a regional aquifer system in SW Saudi Arabia, where matrix, fracture, and large-scale hydraulic conductivities are coincident. The measurements deal with different scales and methods and are based on porosity and permeability measur...

Alluvial fans represent sediment sinks directly at the outlet of the source area in mountain landscapes. They contain multiple information on short-term as well as on long-term changes of sediment supply and of environmental parameters like climate and vegetation. However, most studies on alluvial fans are restricted to selective surface analysis a...

In recent years, outcrop analog studies have become a powerful tool in sedimentology for the assessment of reservoirs, both in hydrocarbon and aquifer studies. Data from exploratory drilling cam-paigns can significantly be augmented by observations on the outcrop of the corresponding stratigraphical interval with the objective to validate the boreh...

Dielectric permittivity is an important parameter for all investigations based on electromagnetic waves (e.g. GPR and TDR measurements). In combination with the electric conductivity, it is crucial for the determination of the propagation velocity, the reflection coefficient and the decay of the electromagnetic wave. The dielectric permittivity dep...

Volcanic terrains such as magmatic arcs are thought to display the most complex surface environments on Earth. Ancient volcaniclastics are notoriously difficult to interpret as they describe the interplay between a single or several volcanoes and the environment. The Early Miocene Tepoztlán Formation at the southern edge of the Transmexican Volcani...

This study presents an almost complete Middle Miocene to Pleistocene sequence of synrift sediments in the western branch of the East African Rift. The studied succession is exposed in several patches on an eastward tilted block between the northern tip of the Rwenzori Block and the eastern shoulder of the Albert Rift. In this position, it reaches a...

In the frame of aquifer studies in Saudi Arabia, we measured porosity and permeability of sandstones of the Palaeozoic Wajid Sandstone in order to get a data base for a regional groundwater model. The Wajid sandstone is subdivided into five formations, which differ in their dominant depositional environment. From the base to the top these are: (i)...

This review paper summarizes the sedimentary and palaeoenvironmental evolution of the Junggar Basin in Northwest China largely based on hardly accessible Chinese language papers, and complemented by own field observations and a critical survey of key sediment cores from petroleum wells. We have combined this information and updated existing lithofa...

The volcaniclastic Tepoztlán Formation (TF) represents an important rock record to unravel the early evolution of the Transmexican Volcanic Belt (TMVB). Here, a depositional model together with a chronostratigraphy of this Formation is presented, based on detailed field observations together with new geochronological, paleomagnetic, and petrologica...

Geochemical signatures of Miocene to Pleistocene sand deposits and potential source rocks including trace elements and REE were used to elucidate long-term changes in weathering and sediment transport in the northernmost part of the western branch of the East African Rift. Since the Pliocene, increased tectonic activity is reflected in deposited sa...

Geochemical signatures of Miocene to Pleistocene sand deposits and potential source rocks including trace elements and REE were used to elucidate long-term changes in weathering and sediment transport in the northernmost part of the western branch of the East African Rift. Since the Pliocene, increased tectonic activity is reflected in deposited sa...

To integrate essential mass resources for urbanisation into a sustainable land use planning, their amount and location and the consequences of their exploitation have to be analysed beforehand. A multi-temporal case study regarding the sand extraction in a small, exemplary area north of Belo Horizonte has been performed which analyses the dynamic o...

Triassic facies development in Central Europe is characterized by two different palaeogeographic settings: (1) the NW Tethys shelf area (Tethyan or Alpine realm) and (2) the northern, peripheral, semi-closed Germanic Basin (Germanic realm). The sedimentary successions of both realms reflect the long-term transgressive evolution following a global s...

In Miocene times, a major volcano-tectonic change took place in West and Central Mexico due to a reorganization of the tectonic plates in the western Pacific region. Since the mid-Miocene, the Transmexican Volcanic Belt (TMVB) began to form. Until present, few data exist on its initial phase since older volcanic products of the TMVB are widely cove...

Recently, multiple studies have documented strong humidity changes for the Late Pleistocene to Holocene on the Altiplano and the Central Andes based on lacustrine sediment cores and ice cores. Although high-resolved reconstructions exist from these archives, few studies looked at the impact of these humidity changes on surface processes in the regi...

Dikes along rivers are a common way to protect urban as well as agricultural areas from floods. Along the Southwest German rivers Rhine and Main construction of dikes started in medieval ages and every generation improved the existing dikes, increased their height, repaired broken ones and added new ones. All these activities are not or insufficien...

This outcrop analogue study investigates Triassic fluvial sandstones of the Stubensandstein Formation which were deposited on a terminal alluvial plain under semi-arid to sub-humid climatic conditions in the land-locked South German Keuper Basin. The Stubensandstein may serve as an analogue for reservoir units in comparable continental basins. Data...

This outcrop analogue study investigates Triassic fluvial sandstones (Stubensandstein Formation) deposited on a terminal alluvial plain under semi‐arid to sub‐humid climatic conditions in the land‐locked South German Keuper Basin. The Stubensandstein may serve as an analogue for reservoir units in comparable continental basins. Data came from studi...

Characterisation and prediction of reservoir heterogeneities require a process understanding of the sedimentary architecture. We propose a simple, process-based methodology to analyse heterogeneities in a rigorously hierarchical way. moving from the smallest to the largest sedimentary units (particles to basins): 1) Microscale heterogeneities: caus...

This paper aims at a quantitative sedimentological and petrophysical characterization of a terminal alluvial plain system exemplified by the Stubensandstein, South German Keuper Basin. The study follows the outcrop-analogue approach, where information derived from outcrops is collected in order to enhance interpretation of comparable subsurface suc...

Outcrops of Upper Triassic (Keuper) alluvial sandstones in South Germany may provide analogues for recently -discovered hydrocarbon reservoirs in the North Sea Triassic. Using an integrated approach, reservoir heterogeneities in the outcropping sandstones may be characterized by means of: (1) sequence stratigraphy (including facies and architectura...

For the analysis of hydrocarbon reservoirs and of aquifers, it is necessary to relate the depositional facies to typical log-signatures and to petrophysical parameters. In order to make such integrated studies of cores more effective, an easy-to-built, cheap and semi-automatical measuring-device was developed. This allows to measure the gamma-ray r...