Monitoring of pore pressures in fine-grained landslide debris covers in southern Italy

2004 ◽  
pp. 643-648
Author(s):  
M Floris ◽  
F Bozzano ◽  
M Lupo
Keyword(s):  
Southern Italy ◽  
Fine Grained ◽  
Pore Pressures ◽  
Landslide Debris

Electrical resistivity tomography investigations in the ufita Valley (southern Italy).

2008 ◽  
Vol 51 (1) ◽  
Author(s):  
A. Giocoli ◽  
C. Magrì ◽  
P. Vannoli ◽  
S. Piscitelli ◽  
E. Rizzo ◽  
...  
Keyword(s):  
Electrical Resistivity ◽  
Electrical Resistivity Tomography ◽  
Southern Italy ◽  
Normal Fault ◽  
Fluvial Sediments ◽  
Resistivity Tomography ◽  
Fine Grained ◽  
Sedimentary Deposits ◽  
Lacustrine Deposits ◽  
Sedimentary Deposit

Several Electrical Resistivity Tomography (ERT) surveys have been carried out to study the subsurface structural and sedimentary settings of the upper Ufita River valley, and to evaluate their efficiency to distinguish the geological boundary between shallow Quaternary sedimentary deposits and clayey bedrock characterized by moderate resistivity contrast. Five shallow ERTs were carried out across a morphological scarp running at the foot of the northeastern slope of the valley. This valley shoulder is characterized by a set of triangular facets, that some authors associated to the presence of a SW-dipping normal fault. The geological studies allow us to interpret the shallow ERTs results obtaining a resistivity range for each Quaternary sedimentary deposit. The tomographies showed the geometrical relationships of alluvial and slope deposits, having a maximum thickness of 30-40 m, and the morphology of the bedrock. The resistivity range obtained for each sedimentary body has been used for calibrating the tomographic results of one 3560m-long deep ERT carried out across the deeper part of the intramountain depression with an investigation depth of about 170 m. The deep resistivity result highlighted the complex alluvial setting, characterized by alternating fine grained lacustrine deposits and coarser gravelly fluvial sediments.

scholarly journals Hydrodynamics in Evaporate-Bearing Fine-Grained Successions Investigated through an Interdisciplinary Approach: A Test Study in Southern Italy—Hydrogeological Behaviour of Heterogeneous Low-Permeability Media

Geofluids ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-15 ◽  
Author(s):  
E. Petrella ◽  
A. Bucci ◽  
K. Ogata ◽  
A. Zanini ◽  
G. Naclerio ◽  
...  
Keyword(s):  
Southern Italy ◽  
Interdisciplinary Approach ◽  
Flow Conditions ◽  
Hydraulic Connection ◽  
Fine Grained ◽  
Test Study ◽  
Aquifer Systems ◽  
Hydraulic Heterogeneity ◽  
Microbiological Data

Messinian evaporates are widely distributed in the Mediterranean Sea as outcropping sediments in small marginal basins and in marine cores. Progressive filling of subbasins led to the formation of complex aquifer systems in different regions where hypersaline and fresh water coexist and interact in different manner. It also generates a significant diversification of groundwater hydrochemical signature and different microbial communities. In the case study, the hydrogeology and hydrochemistry of the whole system are influenced by good hydraulic connection between the shallower pyroclastic horizon and the underlying evaporate-bearing fine-grained Messinian succession. This is demonstrated by the merge of hydrogeological, chemical, isotopic, and microbiological data. No mixing with deep ascending waters has been observed. As shown by geophysical, hydraulic, and microbiological investigations, the hydraulic heterogeneity of the Messinian bedrock, mainly due to karstified evaporitic interstrata/lenses, causes the hydraulic head to significantly vary with depth. Somewhere, the head increases with the depth’s increase and artesian flow conditions are locally observed. Moreover, the metagenomic investigations demonstrated the existence of a poor hydraulic connection within the evaporate-bearing fine-grained succession at metric and decametric scales, therefore leading to a patchwork of geochemical (and microbiological) subenvironments.

Deep-rooted overthrusting and blueschistic metamorphism in compressive continental margins. An example from Calabria (Southern Italy)

1981 ◽  
Vol 118 (5) ◽  
pp. 539-544 ◽  
Author(s):  
Giuseppe Piccarreta
Keyword(s):  
Southern Italy ◽  
Continental Margins ◽  
Upward Motion ◽  
Pore Pressures ◽  
Austroalpine Nappes ◽  
Resistance To Deformation ◽  
Confining Pressures

SummaryAt the base of austroalpine nappes in Calabria alpine greenschist dynamometamorphism is overprinted by blueschist metamorphism. Tectonic overpressures and deep-rooted movements of upthrusting type in compressive regime are the key to generation of blueschistic conditions and to greenschist-bluecschist evolution of metamorphism. The tectonic overpressures are generated because the rocks at higher confining pressures and lower pore pressures have relatively higher resistance to deformation. The evolution from greenschist to blueschist conditions results from cooling during upward motion with overpressures remaining concentrated along the thrust zones.

scholarly journals Initial pore pressures under the Lusi mud volcano, Indonesia

2015 ◽  
Vol 3 (1) ◽  
pp. SE33-SE49 ◽  
Author(s):  
Mark Tingay
Keyword(s):  
Pore Pressure ◽  
Mud Volcano ◽  
Prediction Methods ◽  
Pressure Gradients ◽  
Modern Times ◽  
Fine Grained ◽  
High Magnitude ◽  
Pore Pressures ◽  
Pore Pressure Prediction ◽  
Well Data

The Lusi mud volcano of East Java, Indonesia, remains one of the most unusual geologic disasters of modern times. Since its sudden birth in 2006, Lusi has erupted continuously, expelling more than 90 million cubic meters of mud that has displaced approximately 40,000 people. This study undertakes the first detailed analysis of the pore pressures immediately prior to the Lusi mud volcano eruption by compiling data from the adjacent (150 m away) Banjar Panji-1 wellbore and undertaking pore pressure prediction from carefully compiled petrophysical data. Wellbore fluid influxes indicate that sequences under Lusi are overpressured from only 350 m depth and follow an approximately lithostat-parallel pore pressure increase through Pleistocene clastic sequences (to 1870 m depth) with pore pressure gradients up to [Formula: see text]. Most unusually, fluid influxes, a major kick, connection gases, elevated background gases, and offset well data confirm that high-magnitude overpressures also exist in the Plio-Pleistocene volcanic sequences (1870 to approximately 2833 m depth) and Miocene (Tuban Formation) carbonates, with pore pressure gradients of [Formula: see text]. The varying geology under the Lusi mud volcano poses a number of challenges for determining overpressure origin and undertaking pore pressure prediction. Overpressures in the fine-grained and rapidly deposited Pleistocene clastics have a petrophysical signature typical of disequilibrium compaction and can be reliably predicted from sonic, resistivity, and drilling exponent data. However, it is difficult to establish the overpressure origin in the low-porosity volcanic sequences and Miocene carbonates. Similarly, the volcanics do not have any clear porosity anomaly, and thus pore pressures in these sequences are greatly underestimated by standard prediction methods. The analysis of preeruption pore pressures underneath the Lusi mud volcano is important for understanding the mechanics, triggering, and longevity of the eruption, as well as providing a valuable example of the unknowns and challenges associated with overpressures in nonclastic rocks.

A new–old approach for shallow landslide analysis and susceptibility zoning in fine-grained weathered soils of southern Italy

Geomorphology ◽  
2015 ◽  
Vol 241 ◽  
pp. 371-381 ◽  
Author(s):  
Leonardo Cascini ◽  
Mariantonietta Ciurleo ◽  
Silvio Di Nocera ◽  
Giovanni Gullà
Keyword(s):  
Southern Italy ◽  
Shallow Landslide ◽  
Fine Grained ◽  
Weathered Soils

Chemical and minero-petrographic features of Plio-Pleistocene fine-grained sediments in Calabria, southern Italy

2014 ◽  
Vol 133 (1) ◽  
pp. 101-115 ◽  
Author(s):  
Francesco Perri ◽  
Luigi Borrelli ◽  
Giovanni Gullà ◽  
Salvatore Critelli
Keyword(s):  
Southern Italy ◽  
Fine Grained

Fault rocks within the blueschist metabasalts of the Diamante–Terranova unit (southern Italy): potential fossil record of intermediate-depth subduction earthquakes

2019 ◽  
Vol 156 (10) ◽  
pp. 1771-1782 ◽  
Author(s):  
Stefano Vitale ◽  
Lorenzo Fedele ◽  
Francesco D’Assisi Tramparulo ◽  
Ernesto Paolo Prinzi
Keyword(s):  
Fossil Record ◽  
Southern Italy ◽  
Seismic Events ◽  
Molten Material ◽  
Diagnostic Features ◽  
Fault Rocks ◽  
Intermediate Depth ◽  
Fine Grained ◽  
Selective Preservation ◽  
Frictional Melting

AbstractWe report the first evidence of fault rocks (FRs) developed during high-pressure/low-temperature (HP/LT) subduction-related metamorphism, within quartz+epidote pods embedded in the glaucophane–lawsonite-bearing ophiolitic metabasalts of the Diamante–Terranova unit (Calabria, Italy). FRs occur as relic injections appearing as thin dark seams, locally showing an internal foliation characterized by tabular, curvilinear and meander-like shapes, and consist of very fine grains of glaucophane and titanite, locally including survivor clasts of epidote and lawsonite. Some boudinaged veins show glaucophane fibres in the boudin necks, marking a clear HP/LT syn-metamorphic origin at c. 30 km depth. The injected FRs can be alternatively interpreted either as pseudotachylytes or as fluidized ultracataclasites. Although subsequent recrystallization largely obliterated primary diagnostic features, the occurrence of (i) different-coloured flow streaks, characterized by alternating layers of glaucophane and titanite, (ii) well-developed flow folds and (iii) corroded epidote survivor crystals could indicate a viscous flow of molten material characterized by a non-uniform chemical composition. With this in mind, we support the hypothesis that these fine-grained veins were originally pseudotachylytes generated by the frictional melting of the glaucophane-rich layers of the Diamante–Terranova metabasalts, likely related to seismic events occurring during the Eocene along thrust faults within the subducting oceanic Ligurian lithosphere. The lack of evidence for pseudotachylyte relics in the metabasalt source rock argues for a selective preservation, largely dependent on the efficient mechanical shielding action of the stiffer quartz+epidote pods.

scholarly journals Effect of diagenesis on pore pressures in fine-grained rocks in the Egersund Basin, Central North Sea

2015 ◽  
Author(s):  
Mohsen Kalani ◽  
Mohammad Koochak Zadeh ◽  
Jens Jahren ◽  
Nazmul Haque Mondol ◽  
Jan Inge Faleide
Keyword(s):  
North Sea ◽  
Fine Grained ◽  
Pore Pressures ◽  
Central North Sea

Application of an image management system in microscopy

1992 ◽  
Vol 50 (2) ◽  
pp. 1052-1053
Author(s):  
Richard S. Chemock
Keyword(s):  
Data Storage ◽  
Cost Savings ◽  
Image Data ◽  
Analytical Techniques ◽  
Operational Mode ◽  
Fine Grained ◽  
Image Recording ◽  
Primary Output ◽  
Capacity Data ◽  
Image Management System

One of the most common tasks in a typical analysis lab is the recording of images. Many analytical techniques (TEM, SEM, and metallography for example) produce images as their primary output. Until recently, the most common method of recording images was by using film. Current PS/2R systems offer very large capacity data storage devices and high resolution displays, making it practical to work with analytical images on PS/2s, thereby sidestepping the traditional film and darkroom steps. This change in operational mode offers many benefits: cost savings, throughput, archiving and searching capabilities as well as direct incorporation of the image data into reports.The conventional way to record images involves film, either sheet film (with its associated wet chemistry) for TEM or PolaroidR film for SEM and light microscopy. Although film is inconvenient, it does have the highest quality of all available image recording techniques. The fine grained film used for TEM has a resolution that would exceed a 4096x4096x16 bit digital image.

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