Norbert Kaul

Universität Bremen | Uni Bremen · Department of Geosciences

Heat flow measurements are a standard technique in Geophysics both onshore and offshore. Recently, such measurements became increasingly important in shallow waters. The increasing amount of offshore power installations makes it necessary to have a good knowledge about the subsurface heat flow and the thermal properties of the sediments to optimize...

Mud volcanoes (MVs) are surface structures typically created by episodic discharge of fluids and solids, often associated to onshore and offshore accretionary prisms on convergent plate boundaries. Detailed investigations of ongoing activity and its associated morphological changes, as well as a better understanding of the temporal evolution of the...

Heat flow across marine transform faults and fracture zones has rarely been studied in detail, despite these features representing distinct thermal boundaries within the oceanic lithosphere. Here, we present heat flow measurements across the St Paul Fracture Zone (SPFZ) in the equatorial Atlantic Ocean, from 48 Ma crust in the south to 71 Ma in the...

Gas hydrates stored in the continental margins of the world’s oceans represent the largest global reservoirs of methane. Determining the source and history of methane from gas hydrate deposits informs the viability of sites as energy resources, and potential hazards from hydrate dissociation or intense methane degassing from ocean warming. Stable i...

We present pore-fluid geochemistry and heat-flow data along the SWIM1 fault in the Horseshoe Abyssal Plain (northeastern Atlantic Ocean). The SWIM1 fault is part of the transcurrent plate boundary between Africa and Eurasia and cuts through as much as 5-km-thick sediments overlying >140 Ma oceanic lithosphere. In a number of places, restraining seg...

Until the year 2019 only around 15% of the Earth's seafloor were mapped at fine spatial resolution (<800 m) by multibeam echosounder systems (Wölfl et al., 2019). Most of our knowledge of global bathymetry is based on depths predicted by gravity observations from satellite altimeters. These predicted depths are combined with shipboard soundings to...

Our knowledge of venting at intraplate seamounts is limited. Almost nothing is known about past hydrothermal activity at seamounts, because indicators are soon blanketed by sediment. This study provides evidence for temporary hydrothermal circulation at Henry Seamount, a re-activated Cretaceous volcano near El Hierro island, close to the current lo...

Cruise No. M162 06.03.2020 – 11.04.2020 Ponta Delgada (Portugal) – Emden (Germany) GLORIA-FLOW

Temperature measurements from the water column, along ROV-dives and in the sediment surrounding North Pond, a sediment pond on the western flank of the Mid-Atlantic ridge, are used in an attempt to detect fluid outflow from the upper crust. Heat flow surveys within North Pond suggest hydrothermal fluid circulation beneath the pond. However, since r...

The thermal state of polar continental crust plays a crucial role for understanding the stability and thickness of large ice sheets, the visco-elastic response of the solid Earth due to unloading when large ice caps melt and, in turn, the accuracy of future sea-level rise prediction. Various studies demonstrate the need for precise measurements and...

A transect of seafloor heat probe measurements on the Hikurangi Margin shows a significant increase of thermal gradients upslope of the up-dip limit of gas hydrate stability at the seafloor. We interpret these anomalously high thermal gradients as evidence for a fluid pulse leading to advective heat flux while endothermic cooling from gas hydrate d...

Focused research on the Pine Island and Thwaites glaciers, which drain the West Antarctic Ice Shelf (WAIS) into the Amundsen Sea Embayment (ASE), revealed strong signs of instability in recent decades that result from variety of reasons, such as inflow of warmer ocean currents and reverse bedrock topography and has been established as the Marine Ic...

Circulation of water at moderate depths in subduction zones is dominantly driven by clay mineral dehydration over distinct pressure and temperature gradients. The signature of these dehydration reactions is found in mud volcano pore waters, however, it is largely unknown, how much of the deep-seated fluids are emitted at mud volcanoes. To unravel t...

On the basis of heat flow measurements, seismic mapping, and sediment pore-water analysis, we demonstrate widespread and efficient ventilation of the 18-22 Ma oceanic crust of the northeast equatorial Pacific Ocean. Recharge and discharge appear to be associated with basement outcrops, including seamounts and north-south-trending faults along which...

We acquired seismic and heat flow data and collected sediment cores in three areas in the Guatemala Basin (Cocos Plate, Eastern Pacific) to investigate the process by which depressions (pits) in the sedimentary cover on young oceanic crust were formed. Median heat flow of 55 mW/m 2 for the three areas is about half of the expected conductive coolin...

This study presents the assessment of total cone resistance from in situ deceleration measurements using the Lance Insertion Retardation meter (LIRmeter) in the Southern North Sea. The penetrometer is equipped with a measurement lance that is up to 6 m in length. The aim was to validate LIRmeter data interpretation within the regional geological co...

We report on newly discovered mud volcanoes located at ~4500 m water depth ~90 km west of the deformation front of the accretionary wedge of the Gulf of Cadiz, and thus outside of their typical geotectonic environment. Seismic data suggest that fluid flow is mediated by a >400-km-long strike-slip fault marking the transcurrent plate boundary betwee...

The development of bottom simulating reflectors (BSRs) and the gas hydrate stability zone (GHSZ) in continental margins is related to recent depositional and tectonic processes. This interrelation is important for understanding the potential resource of gas hydrate deposits. The purpose of this study is to understand the influence of such activity...

A number of deep sea mud volcanoes (>4700 m water depth) were discovered during a recent expedition with the German research vessel Meteor along a prominent WSW-ENE trending strike-slip fault (SWIM 1; Zitellini et al., 2009) in the western extension of the Gulf of Cadiz (NE Atlantic). Mud volcanism was unambiguously related to tectonic activity alo...

The development of bottom simulating reflectors (BSRs) and the gas hydrate stability zone (GHSZ) in continental margins is related to recent depositional and tectonic processes. This interrelation is important for understanding the potential resource of gas hydrate deposits. The purpose of this study is to understand the influence of such activity...

Within this paper we present the Lance Insertion Retardation meter (LIRmeter) as an instrument to determine the strength of marine sediments by a measurement of the deceleration of a probe during penetration into the seafloor. The instrument has been designed for the penetration of the upper 4 m of marine sediments and is therefore suitable for sit...

The scientific goal of the project "SeamountFlux" is to study a process which can possibly contribute significantly to large scale cooling of the oceanic crust. The focus of the study is to investigate the exchange of matter and energy between the ocean and the upper young oceanic crust in the vicinity of unexplained circular depressions in the sed...

Physical and geotechnical parameters of marine sediments are of vital interest to fields like foundation-planning of offshore structures, surveying of cable routes, sediment dynamics, sediment manipulation (dredging, plowing), ground-truthing of acoustical surveys, risk assessment and mine burial predictions. Therefore, characterization of geotechn...

The Gakkel Ridge in the Arctic Ocean with its adjacent Nansen and Amundsen Basins is a key region for the study of mantle melting and crustal generation at ultraslow spreading rates. We use free-air gravity anomalies in combination with seismic reflection and wide-angle data to compute 2-D crustal models for the Nansen and Amundsen Basins in the Ar...

Expedition SO207 took place from June 21, 2010 until July 13, 2010 at 8°N / 90°W, approximately 360 nm offshore Costa Rica in the eastern Pacifc Ocean. On board were scientists with expertise in geophysics and geochemistry from the University of Bremen and the University of Bern. The scientific goal was to study the exchange of matter and energy b...

FIELAX GmbH is an SME (Small and Medium Enterprise) specialized in operating research platforms and scientific measurements. We have developed a Heat Flow Probe for a wide application range and easy handling featuring an active length of 6 m. The new probe is the follow-up of a prototype that was created at the University of Bremen (Germany), Prof....

Universität Bremen has developed a lance insertion retardation (LIR) meter, which is an inexpensive, small and autonomously operating device that can be tied to any type of lance like a gravity corer, a heat probe or a bare rod. The LIR meter can operate in any depth and records data of the retarded motion of a lance while a soil sampling and/or a...

a b s t r a c t Heat flow anomalies provide critical information in active tectonic environments. The Gulf of Cadiz and adjacent areas are affected by the plate convergence between Africa and Europe, causing widespread deformation and faulting. Active thrust faults cause lateral movement and advection of heat that produces systematic variations in...

While planning the COAST Expedition to the Siberian Laptev Sea in 2005, the question of how to make a short equilibrium temperature measurement in a dry borehole arose. As a result, an infrared borehole tool was developed and used in three dry boreholes (up to 60.2 m deep) in the coastal transition zone from terrestrial to sub-sea permafrost near M...

Fluids are suspected to play a major role in the nucleation and rupture propagation of earth-quakes. In Chile, seismological data were previously interpreted to indicate that fluids captured in the fault zone are released periodically during large underthrust earthquakes, leading to post-seismic fluid flow. In central Chile, heat flow derived from...

From the Hakon Mosby Mud Volcano (HMMV) on the southwest Barents Sea shelf, gas and fluids are expelled by active mud volcanism. We studied the mass transfer phenomena and microbial conversions in the surface layers using in situ microsensor measurements and on retrieved cores. The HMMV consists of three concentric habitats: a central area with gra...

The HAkon Mosby Mud Volcano (HMMV), located on the Norwegian-Barents-Svalbard continental margin in 1250 m water depth, has been identified and described as a structure caused by upward transport of mud, pore water and gas [e.g. Eldhohn, O., Sundvor, E., Vogt, P.R., Hjelstuen, B.O., Crane, K., Nilsen, A.K., Gladczenko, T.P., 1999. SW Barents Sea co...

Lithospheric deformation near the Chile Triple Junction is under investigation in the TIPTEQ (from The Incoming Plate to mega-Thrust EarthQuake processes) project. During R/V Sonne cruise SO181 (December 2004 to February 2005) various geophysical and geological data sets along several large transects across differently aged subducting oceanic litho...

Detailed heat flow surveys on the oceanic trench slope offshore Nicaragua and Central Chile indicate heat flow values lower than the expected conductive lithospheric heat loss and lower than the global mean for crust of that age. Both areas are characterised by pervasive normal faults exposing basement in a setting affected by bending-related fault...

Shallow gas hydrate accumulation in mud volcanoes in the Costa Rica forearc was postulated before, but is now proven by a find in surface sediments at the southwestern slope of the recently discovered Mound 11, a mud volcano located 30 km arcward from the trench, on the continental slope off Costa Rica at 1000 m water depth. The gas hydrate content...

Almost 24 percent of the northern hemisphere are under permafrost influence. A special variety is the submarine or sub-sea permafrost proposed on the Laptev-Sea shelf in Siberia. However, temperatures far below the freezing point can establish in soils only under subaeric conditions without ice-cover. Submarine permafrost is considered to be a reli...

Mud extrusion is frequently observed as a dewatering phenomenon in compressional tectonic settings such as subduction zones. Along the Middle American Trench, several of these features have been recently discovered. This paper presents a heat flow study of actively venting Mound Culebra, offshore Nicoya Peninsula, and is complemented by data from g...

Seasonal variations of subsea floor temperatures in the eastern Mecklenburg Bay, Baltic Sea.

In the fall of 2001 a field trip was made with the research vessel FS Heincke, cruise HE 158, into the southern Baltic Sea. During the cruise, in situ temperature measurements were carried out in the sediment of the western and eastern part of the Mecklenburg Bay. For the first time, a 6 m long temperature probe was used in this area. The main inte...

The design of a new 6m long violin-bow marine heat probe and first successful tests and data collected off Costa Rica are presented. The data were collected during cruise M54-2 on RV METEOR in August 2002. The mechanically robust heat probe is designed for the operation in a pogo-style mode with a wide application range from 6000m deep sea trenches...

New geophysical data have become available from shipborne and satellite measurements allowing a re-evaluation of the largely unknown junction of the Arctic spreading centre and the northeastern Siberian continental margin where the transpolar mid-ocean Gakkel Ridge abuts against the continental slope of the Laptev Sea. Based on multichannel seismic...

Sediment cover over mid-ocean ridges is expected generally to thicken with seafloor age and distance from spreading center, reflecting symmetric sediment accumulation on both flanks of the ridge. In high quality reflection seismic records and sediment echosounding measurements recently collected across the East Pacific Rise we find a strong asymmet...

Recent publications suggest that most of the fluid flow in the upper oceanic crust is channelized through small volumes of rock and vented into the ocean. This implies that at flanks of generally thinly sedimented mid-ocean ridges, focused discharge at the seafloor should be concentrated most likely at outcrops, high-angle normal faults or seamount...

Géli et al. [2001] ( Eos , 17 July 2001, p.317) present sub‐sea floor thermal profiles collected with temperature sensors and data loggers attached to 18‐m‐long sediment cores. Some of these thermal profiles include significant non‐linearities, particularly within the shallowest 5 m below sea floor (mbsf). Géli et al. [2001] assert that thermal dat...

During the German research cruise SO-124 on RV Sonne (fall 1997) on the Makran accretionary wedge off Pakistan, geophysical investigations were carried out to study the thermal regime at a gas hydrate bearing sediment in a tectonically deformed accretionary wedge. On a transect perpendicular to the strike of the deformation front 42 heat flow measu...

In order to investigate the impact of off-axis hydrothermal circulation on changes of the seismic properties of upper oceanic crust (layer 2A), we performed an extensive geophysical survey on the eastern flank of the East Pacific Rise at 14°S. Seismic refraction and heat flow data were obtained along a 720-km-long and 25 to 40-km wide corridor, cov...

The oceanic crust covers almost 57% of the Earth's surface and is created by seafloor spreading at mid‐ocean ridges. Although crustal structure is similar everywhere, seismic experiments near spreading ridges indicate that seismic velocities in the top of the igneous crust are typically much lower than those in mature oceanic crust. While profound...

A c. 500 km wide rim of the continental margin of western Dronning Maud Land was tectono-thermally affected during the Gondwana fragmentation. This has been determined by apatite fission-track dating of the basement in Heimefrontfjella and Mannefallknausane and from geomorphological aspects. The continental crust of western Dronning Maud Land was h...

The Antarctic Peninsula has a remarkable record of active margin processes, which include subduction with progressive ridge-trench collisions, margin segmentation by major fracture zones, rifting in a hybrid back-arc and sheared plate margin context, fore-arc development and glacial-marine controlled trench fill processes. Several facets of these m...

From seismic measurements of Kapp Norvegia and the results of ODP Leg 113 it was possible to create a stratotype for the sedimentation of the eastern continental margin of the Weddell Sea. Fault control of the erosion-appearing Wegener Canyon is suggested. The sedimentary structure of the Explora Escarpment could be revealed by high resolution seis...

High-resolution reflection seismic investigations have been carried out along the eastern margin of the Weddell Sea by R.V. Polarstern in the austral summer 1986–1987. The very high resolution achieved on most profiles allows a refinement of previous seismostratigraphic work in this region. Two main survey areas are discussed in this paper: (a) a s...

The continental margin off Peru is dominated by the oblique subduction of the Nazca Plate and Nazca Ridge. The sedimentary wedge consists of folded and uplifted material. Along with compression, compaction, folding and faulting, processes of dewatering, material and energy migration occur. Bottom simulating reflectors (BSRs) are detectable in locat...

Mud volcanism is a common dewatering phenomenon in compressional tectonic scenarios such as subduction zones. Offshore Costa Rica and Nicaragua, several of these features have been discovered, the most prominent of which is Mound Culebra north-west of Nicoya Peninsula. A methane anomaly over the mound, authigenic carbonate formation at its crest, a...