Rifting and Shallow-Dipping Detachments, Clues from the Corinth
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Verification of Vulnerable Zones Identified Under the Nitrate Directive \ and Sensitive Areas Identified Under the Urban Waste W
CONTENTS 1 INTRODUCTION 1 1.1 THE URBAN WASTEWATER TREATMENT DIRECTIVE (91/271/EEC) 1 1.2 THE NITRATES DIRECTIVE (91/676/EEC) 3 1.3 APPROACH AND METHODOLOGY 4 2 THE OFFICIAL GREEK DESIGNATION PROCESS 9 2.1 OVERVIEW OF THE CURRENT SITUATION IN GREECE 9 2.2 OFFICIAL DESIGNATION OF SENSITIVE AREAS 10 2.3 OFFICIAL DESIGNATION OF VULNERABLE ZONES 14 1 INTRODUCTION This report is a review of the areas designated as Sensitive Areas in conformity with the Urban Waste Water Treatment Directive 91/271/EEC and Vulnerable Zones in conformity with the Nitrates Directive 91/676/EEC in Greece. The review also includes suggestions for further areas that should be designated within the scope of these two Directives. Although the two Directives have different objectives, the areas designated as sensitive or vulnerable are reviewed simultaneously because of the similarities in the designation process. The investigations will focus upon: • Checking that those waters that should be identified according to either Directive have been; • in the case of the Nitrates Directive, assessing whether vulnerable zones have been designated correctly and comprehensively. The identification of vulnerable zones and sensitive areas in relation to the Nitrates Directive and Urban Waste Water Treatment Directive is carried out according to both common and specific criteria, as these are specified in the two Directives. 1.1 THE URBAN WASTEWATER TREATMENT DIRECTIVE (91/271/EEC) The Directive concerns the collection, treatment and discharge of urban wastewater as well as biodegradable wastewater from certain industrial sectors. The designation of sensitive areas is required by the Directive since, depending on the sensitivity of the receptor, treatment of a different level is necessary prior to discharge. -
Preliminary Catalog of the Sedimentary Basins of the United States
Preliminary Catalog of the Sedimentary Basins of the United States By James L. Coleman, Jr., and Steven M. Cahan Open-File Report 2012–1111 U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior KEN SALAZAR, Secretary U.S. Geological Survey Marcia K. McNutt, Director U.S. Geological Survey, Reston, Virginia: 2012 For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment, visit http://www.usgs.gov or call 1–888–ASK–USGS. For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprod To order this and other USGS information products, visit http://store.usgs.gov Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this information product, for the most part, is in the public domain, it also may contain copyrighted materials as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner. Suggested citation: Coleman, J.L., Jr., and Cahan, S.M., 2012, Preliminary catalog of the sedimentary basins of the United States: U.S. Geological Survey Open-File Report 2012–1111, 27 p. (plus 4 figures and 1 table available as separate files) Available online at http://pubs.usgs.gov/of/2012/1111/. iii Contents Abstract ...........................................................................................................................................................1 -
From Orogeny to Rifting: When and How Does Rifting Begin? Insights from the Norwegian ‘Reactivation Phase’
EGU21-469 https://doi.org/10.5194/egusphere-egu21-469 EGU General Assembly 2021 © Author(s) 2021. This work is distributed under the Creative Commons Attribution 4.0 License. From orogeny to rifting: when and how does rifting begin? Insights from the Norwegian ‘reactivation phase’. Gwenn Peron-Pinvidic1,2, Per Terje Osmundsen2, Loic Fourel1, and Susanne Buiter3 1NGU - Geological Survey of Norway, 7040 Trondheim, Norway 2NTNU - Norwegian University of Science and Technology, 7491 Trondheim, Norway 3Tectonics and Geodynamics, RWTH Aachen University, 52064 Aachen, Germany Following the Wilson Cycle theory, most rifts and rifted margins around the world developed on former orogenic suture zones (Wilson, 1966). This implies that the pre-rift lithospheric configuration is heterogeneous in most cases. However, for convenience and lack of robust information, most models envisage the onset of rifting based on a homogeneously layered lithosphere (e.g. Lavier and Manatschal, 2006). In the last decade this has seen a change, thanks to the increased academic access to high-resolution, deeply imaging seismic datasets, and numerous studies have focused on the impact of inheritance on the architecture of rifts and rifted margins. The pre-rift tectonic history has often been shown as strongly influencing the subsequent rift phases (e.g. the North Sea case - Phillips et al., 2016). In the case of rifts developing on former orogens, one important question relates to the distinction between extensional structures formed during the orogenic collapse and the ones related to the proper onset of rifting. The collapse deformation is generally associated with polarity reversal along orogenic thrusts, ductile to brittle deformation and important crustal thinning with exhumation of deeply buried rocks (Andersen et al., 1994; Fossen, 2000). -
Cenozoic Thermal, Mechanical and Tectonic Evolution of the Rio Grande Rift
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 91, NO. B6, PAGES 6263-6276, MAY 10, 1986 Cenozoic Thermal, Mechanical and Tectonic Evolution of the Rio Grande Rift PAUL MORGAN1 Departmentof Geosciences,Purdue University,West Lafayette, Indiana WILLIAM R. SEAGER Departmentof Earth Sciences,New Mexico State University,Las Cruces MATTHEW P. GOLOMBEK Jet PropulsionLaboratory, CaliforniaInstitute of Technology,Pasadena Careful documentationof the Cenozoicgeologic history of the Rio Grande rift in New Mexico reveals a complexsequence of events.At least two phasesof extensionhave been identified.An early phase of extensionbegan in the mid-Oligocene(about 30 Ma) and may have continuedto the early Miocene (about 18 Ma). This phaseof extensionwas characterizedby local high-strainextension events (locally, 50-100%,regionally, 30-50%), low-anglefaulting, and the developmentof broad, relativelyshallow basins, all indicatingan approximatelyNE-SW •-25ø extensiondirection, consistent with the regionalstress field at that time.Extension events were not synchronousduring early phase extension and were often temporally and spatiallyassociated with major magmatism.A late phaseof extensionoccurred primarily in the late Miocene(10-5 Ma) with minor extensioncontinuing to the present.It was characterizedby apparently synchronous,high-angle faulting givinglarge verticalstrains with relativelyminor lateral strain (5-20%) whichproduced the moderuRio Granderift morphology.Extension direction was approximatelyE-W, consistentwith the contemporaryregional stress field. Late phasegraben or half-grabenbasins cut and often obscureearly phasebroad basins.Early phase extensionalstyle and basin formation indicate a ductilelithosphere, and this extensionoccurred during the climax of Paleogenemagmatic activity in this zone.Late phaseextensional style indicates a more brittle lithosphere,and this extensionfollowed a middle Miocenelull in volcanism.Regional uplift of about1 km appearsto haveaccompanied late phase extension, andrelatively minor volcanism has continued to thepresent. -
The Great Rift Valley the Great Rift Valley Stretches from the Floor of the Valley Becomes the Bottom Southwest Asia Through Africa
--------t---------------Date _____ Class _____ Africa South of the Sahara Environmental Case Study The Great Rift Valley The Great Rift Valley stretches from the floor of the valley becomes the bottom Southwest Asia through Africa. The valley of a new sea. is a long, narrow trench: 4,000 miles (6,400 The Great Rift Valley is the most km) long but only 30-40 miles (48-64 km) extensive rift on the Earth's surface. For wide. It begins in Southwest Asia, where 30 million years, enormous plates under it is occupied by the Jordan River and neath Africa have been pulling apart. the Dead Sea. It widens to form the basin Large earthquakes have rumbled across of the Red Sea. In Africa, it splits into an the land, causing huge chunks of the eastern and western branch. The Eastern Earth's crust to collapse. Rift extends all the way to the shores of Year after year, the crack that is the the Indian Ocean in Mozambique. Great Rift Valley widens a bit. The change is small and slow-just a few centimeters A Crack in the Ea rth Most valleys are carved by rivers, but the Great Rift Valley per year. Scientists believe that eventually is different. Violent forces in the Earth the continent will rip open at the Indian caused this valley. The rift is actually Ocean. Seawater will pour into the rift, an enormous crack in the Earth's crust. flooding it all the way north to the Red Along the crack, Africa is slowly but surely splitting in two. -
4. Deep-Tow Observations at the East Pacific Rise, 8°45N, and Some Interpretations
4. DEEP-TOW OBSERVATIONS AT THE EAST PACIFIC RISE, 8°45N, AND SOME INTERPRETATIONS Peter Lonsdale and F. N. Spiess, University of California, San Diego, Marine Physical Laboratory, Scripps Institution of Oceanography, La Jolla, California ABSTRACT A near-bottom survey of a 24-km length of the East Pacific Rise (EPR) crest near the Leg 54 drill sites has established that the axial ridge is a 12- to 15-km-wide lava plateau, bounded by steep 300-meter-high slopes that in places are large outward-facing fault scarps. The plateau is bisected asymmetrically by a 1- to 2-km-wide crestal rift zone, with summit grabens, pillow walls, and axial peaks, which is the locus of dike injection and fissure eruption. About 900 sets of bottom photos of this rift zone and adjacent parts of the plateau show that the upper oceanic crust is composed of several dif- ferent types of pillow and sheet lava. Sheet lava is more abundant at this rise crest than on slow-spreading ridges or on some other fast- spreading rises. Beyond 2 km from the axis, most of the plateau has a patchy veneer of sediment, and its surface is increasingly broken by extensional faults and fissures. At the plateau's margins, secondary volcanism builds subcircular peaks and partly buries the fault scarps formed on the plateau and at its boundaries. Another deep-tow survey of a patch of young abyssal hills 20 to 30 km east of the spreading axis mapped a highly lineated terrain of inactive horsts and grabens. They were created by extension on inward- and outward- facing normal faults, in a zone 12 to 20 km from the axis. -
Rift-Valley-1.Pdf
R E S O U R C E L I B R A R Y E N C Y C L O P E D I C E N T RY Rift Valley A rift valley is a lowland region that forms where Earth’s tectonic plates move apart, or rift. G R A D E S 6 - 12+ S U B J E C T S Earth Science, Geology, Geography, Physical Geography C O N T E N T S 9 Images For the complete encyclopedic entry with media resources, visit: http://www.nationalgeographic.org/encyclopedia/rift-valley/ A rift valley is a lowland region that forms where Earth’s tectonic plates move apart, or rift. Rift valleys are found both on land and at the bottom of the ocean, where they are created by the process of seafloor spreading. Rift valleys differ from river valleys and glacial valleys in that they are created by tectonic activity and not the process of erosion. Tectonic plates are huge, rocky slabs of Earth's lithosphere—its crust and upper mantle. Tectonic plates are constantly in motion—shifting against each other in fault zones, falling beneath one another in a process called subduction, crashing against one another at convergent plate boundaries, and tearing apart from each other at divergent plate boundaries. Many rift valleys are part of “triple junctions,” a type of divergent boundary where three tectonic plates meet at about 120° angles. Two arms of the triple junction can split to form an entire ocean. The third, “failed rift” or aulacogen, may become a rift valley. -
Processes Affecting Recent and Future Evolution of the Xylokastro Beach Zone (Gulf of Corinth, Greece)
Processes affecting recent and future evolution of the Xylokastro beach zone (Gulf of Corinth, Greece) Andreas Valaouris1 1Department of Geography & Climatology, 1 Serafim Poulos * Faculty of Geology & Geoenvironment, 1 Stelios Petrakis University of Athens, Panepistimioupolis, 2 George Alexandrakis Zografou, 15784, Greece Emmanuel Vassilakis1 2Institute of Applied & Computational Mathematics, Foundation for Research and Technology, Hellas, N. Plastira 100, Vassilika Vouton, 70013 Heraklion, Crete, Greece *Corresponding author: tel: +30 210 72 74 143 fax: +30 210 72 74 143 e-mail: [email protected] ABSTRACT The aim of the present study is to investigate the morphodynamic regime of the coastal area of Xylokastro (north coast of Peloponnese), in order to identify and evaluate the processes controlling its formation and evolution. Within this concept, the following factors have been considered and evaluated: near-shore morphometry and granulometry along shore-normal profiles, the direction and potential volumes of long- and cross-shore, induced by the incoming offshore waves, the decadal and future trends of coastline displacement, the available information for terrestrial sediment influx and the geological processes operating in the broader coastal region of Xylokastro (i.e. subaqueous slides) and the human interference. On the basis of these results, the formation and evolution of this coastal stretch seems to be governed primarily by the neotectonic activity and the relative change of sea level rise, and secondarily by the wave-induced near-shore sediment transport; the role of the latter could be enhanced substantially by the human intervention (i.e. construction of marina, seafront walls). Moreover, the expected eustatic increase in sea level by the year 2100, could cause a coastline retreat up to 9 m (SLR=0.38 m) or >19 m (SLR≥1 m). -
Late Quaternary Rates of Stream Incision in Northeast Peloponnese, Greece
Front. Earth Sci. 2016, 10(3): 455–478 DOI 10.1007/s11707-016-0577-0 RESEARCH ARTICLE Late Quaternary rates of stream incision in Northeast Peloponnese, Greece Efthimios KARYMBALIS (✉)1, Dimitrios PAPANASTASSIOU2, Kalliopi GAKI-PAPANASTASSIOU3, Maria FERENTINOU4, Christos CHALKIAS1 1 Department of Geography, Harokopio University, Athens 17671, Greece 2 Institute of Geodynamics, National Observatory of Athens, Athens 11810, Greece 3 Department of Geography and Climatology, Faculty of Geology and Geoenvironment, National and Kapodistrian University of Athens, Athens 15784, Greece 4 Department of Geology, School of Agricultural, Earth and Environmental Sciences, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban 4000, South Africa © Higher Education Press and Springer-Verlag Berlin Heidelberg 2016 Abstract This study focuses on defining rates of fluvial Downcutting rates are comparable with the rock uplift incision for the last 580Æ5 kyr along valley systems of rates, which range from 0.4Æ0.02 mm/yr to 1.49Æ0.12 eight streams that drain the eastern part of the northern mm/yr, over the last 330Æ5 kyr. Peloponnese. The streams are developed on the uplifted block of the offshore-running Xylokastro normal fault, one Keywords fluvial incision, tectonic uplift, marine ter- of the main faults bounding the southern edge of the Gulf races, Peloponnese, Greece of Corinth half-graben, and have incised a set of ten uplifted marine terraces having an amphitheatric shape. These terraces range in age from 60Æ5 kyr to 580Æ5 kyr 1 Introduction and have been mapped in detail and correlated with late Pleistocene oxygen-isotope stages of high sea-level stands The landscape in actively deforming areas results from by previous studies. -
Seismogenic Sources and Related Active Faults in the Gulf of Corinth; a Combined Approach
Ll.EArio TI1~ EAA~VIKrj~ rEwAoYIKrj~ ETalpio~ TO~, XXX)( Bulletin of the Geological Society of Greece voL XXXX, 2007 2007 Proceedings of the 11'" International Congress, Athens, May, npOKTIKcl 11°' Ll.IE8vou~ l:uvEiSpiou, A8rjvo, Malo<; 2007 2007 SEISMOGENIC SOURCES AND RELATED ACTIVE FAULTS IN THE GULF OF CORINTH; A COMBINED APPROACH l Segou M. , and Lozios S.2 I National and Kapodistrian University ofAthens, Faculty ofGeology and Geoenvironment, Department ofGeophusics-Geothermics, msegou@geol- uoa,gr 1 National and Kapodistrian University ofAthens, Faculty ofGeology and Geoenvironment, Department ofDynamic Tectonic and Applied Geology, [email protected] Abstract The neotectonic graben of Corinth gulfforms an interesting case study from the geodynamical and seismological point of view, since specific characteristics met on the fault zones around the gulf and the adjacent seismological data pose several questions related with the overall modern activity across a number of neotectonic faults. Indexing active fault zones with structural, seismological and sedimentological criteria leads to thorough understanding of the evolution and modern activity and provide researchers useful tools in order to evaluate the degree ofpresent day activity ofthe broader area. The combined approach proposed here, with joint use of both, seismogenic sources and structural evidence, contributes to the re-evaluation ofthe earthquake potential by assessing the role ofactive features in the already complex geodynamic environment ofthe Corinthian gulf Key words: neotectonic, earthquake fau It, Greece. n£pfA 'l4J'l To VWTfXroVZKO [JiJe/all(/. TOV KOpIVeUJ-KOV KO,17[OV areOTE:Aci pia u5w.irE:plJ m:pbrwlal7 areo ycw6vvapzKr,c; K(J./ (JE:/apo},oY1Kr,C; Cr.reolf/17r;, Kaewc; m L(jtalrCpa xapaICr17PUJTZKCr. -
Fault Geometry and Kinematics Within the Terror Rift, Antarctica THESIS
Fault Geometry and Kinematics within the Terror Rift, Antarctica THESIS Presented in Partial Fulfillment of the Requirements for the Degree Master of Science in the Graduate School of The Ohio State University By William B. Blocher Graduate Program in Earth Sciences The Ohio State University 2017 Master's Examination Committee: Dr. Terry Wilson, Advisor Dr. Thomas Darrah Dr. Derek Sawyer Copyrighted by William B. Blocher 2017 Abstract The Terror Rift is the youngest expression of the intraplate West Antarctic Rift System that divides the Antarctic continent. Previous studies of the Terror Rift have ascribed a variety of interpretations to its structure, and especially to the regional anticline known as the Lee Arch, which has been explained as a transtensional flower structure, a rollover anticline, and as the result of magmatic inflation. Fault mapping and the documentation of stratal dips in this study have revealed a Terror Rift structure characterized by north-south folds and a complex distribution of faults. Nearly all faults have normal sense dip separation. A continuous zone of west-dipping faults with relatively high-magnitude normal separation are interpreted to be the border fault system defining the eastern margin of Terror Rift. Reconstruction of listric ramp-flat geometry of this border fault system explains intrarift fold and fault patterns well. Zonation of structures indicates that the listric rift detachment faults are segmented along the rift axis. This new model for rift structure indicates orthogonal rift extension in the ENE- WSW direction, with low strains of <10% calculated from bed-length balancing. i Acknowledgments To my advisor, Dr. -
Developing a Biotic River Typology and Defining Reference Conditions in the Rivers of Greece: a Spatially- Based Approach
Developing a biotic river typology and defining reference conditions in the rivers of Greece: a spatially- based approach A.N. Economou, S. Zogaris, S. Giakoumi, R. Barbieri & D. Petridis Abstract Developing a biotic river typology and reference conditions are vital components of ecological assessment using fish. In Greece, due to the absence of systematic monitoring data, fish sampling data from previous ichthyological surveys conducted primarily in the southern and western parts of the Hellenic Western Balkan ecoregion (Illies' ecoregion 6) were utilised. These surveys were undertaken for the purpose of fish conservation and were not designed with the prospect of ecological assessments. As a consequence, the sampling methodologies, the site selection criteria, the analytical procedures and the recorded parameters were not in line with the requirements of the WFD. A brief synopsis of the main environmental features of the Greek rivers which indicate a remarkable environmental heterogeneity is presented. Greece is a geographically fragmented mountainous country with a large number of medium and small sized rivers. Most rivers run through narrow mountain valleys that descend abruptly to the coast. Usually a mountain river becomes a lowland river very near its estuary. As a result many small and medium sized rivers have a flashy and erosive behavior and suffer from the lack of lowland riverine habitat. Lowland rivers are usually small; large floodplain rivers are very few, almost wholly restricted to northern Greece. Precipitation is irregularly distributed and hydrology varies remarkably among basins. Semi-arid regions and areas with seasonally arid conditions exist in parts of the south and southeast where localized karstic springs play an important role in enabling perennial water flows.