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Competence Level: N144: Rift Systems, Faulting and 5 Days Skilled Fault-Controlled Sedimentary Architecture: Gulf of Corinth Field Course (Greece) Classroom Elements Instructor(s): Mary Ford and Ed Williams Low Physical Demand Summary This course evaluates rift stratigraphy and structure, the geometry and kinematics of a normal fault network and the facies of selected Gilbert-type fan deltas. Participants will examine fluvial successions, fan deltas and turbidites deposited in an active rift; the controlling factors in delta construction and distribution; geometry, connectivity and growth of a normal fault network; the interaction of surface processes and tectonics in active rifts. This course will primarily be of use in exploration but is also applicable to reservoirs and oil fields in extensional settings during appraisal, development and production. Learning Outcomes Participants will learn to: 1. Assess the tectonic setting and evolution of the Corinth Rift; evaluate the rapidity and scale of the rifting processes compared with other rift systems. 2. Evaluate the geometry, kinematics and evolution of a normal fault system. 3. Understand the evolution of rift stratigraphic architecture in time and space. 4. Assess geometry and sediment infill of an individual fault block. 5. Construct a cross-section through part of the rift. Calculate the heave and throw of faults, individually and cumulatively. 6. Compare and contrast fault block stratal and structural geometries, including syn-sedimentary block tilting and folding. 7. Evaluate the role of inherited palaeotopography in rift basins. 8. Examine a detailed case history of relay ramp evolution and assess its influence on sedimentary input and the location of deltas. 9. Describe and interpret the stratal architecture and key surfaces of a Gilbert-delta and evaluate operative tectonic versus eustatic controls. 10. Compare models for rifting and normal fault growth mechanisms, strain localisation and the effects on sediment distribution. 11. Analyse sediment routing systems in an evolving rift and their influence on the distribution of sediments (thickness and facies). Duration and Training Method This is a five-day course, consisting primarily of field work with some classroom tuition. The proportion of field and classroom time is approximately 80/20. Classwork will comprise presentations and practical exercises such as construction of cross sections. Outcrop investigations will be linked to subsurface examples with a particular emphasis on reservoir geology. Course Outline Competence Level: N144: Rift Systems, Faulting and 5 Days Skilled Fault-Controlled Sedimentary Architecture: Gulf of Corinth Field Course (Greece) Classroom Elements Instructor(s): Mary Ford and Ed Williams Low Physical Demand Physical Demand The physical demands for this class are LOW according to the Nautilus Training Alliance field course grading system. There will be multiple walks of up to 1 km (0.5 miles) most days. The longest walk is approximately 3 km (1.5 miles) with an ascent (and descent) of 200 m (80 feet). The field area is at an elevation approximately 300 m (1000 ft) and conditions are variable but likely to be hot. There may be rain from late autumn to early spring. Transport will be by minicoach on paved roads. Who Should Attend The course is relevant for all geoscientists who wish to broaden and deepen their knowledge of tectonics and sedimentation in rift systems. The course will provide a working knowledge of these systems for graduates and inexperienced staff, while providing deeper insights to more experienced participants for more detailed application to subsurface projects. Multidisciplinary teams working assets in extensional settings would benefit from collaborating in this field environment. Prerequisites and Linking Courses It is assumed that participants will have a basic knowledge of structural geology and sedimentology and be familiar with associated terminology before attending the class. This course is complementary to other courses focusing on extensional tectonics and fault systems such as N041 (Extensional Tectonics and Normal Fault Patterns, Utah). Course Content The Gulf of Corinth is one of the fastest opening rifts in the world with a rate of NS extension of up to 1.6 cm/yr. On the south side of the Gulf, the rift’s tilted fault blocks and their synrift succession (Late Pliocene-Middle Pleistocene) are exceptionally well-exposed due to rapid uplift up to 1200 m and deep incision by rivers. The onshore clastic rift succession, up to 2.8 km thick, includes a series of spectacular giant Gilbert-type fan deltas (up to 800 m thick, radii up to 4 km) that are used as analogues for reservoirs. These are exposed on cliffs up to 800 m high, where their stratigraphic architecture and facies can be studied in detail. Theme 1 The behaviour of the normal fault network during evolution of the rift, in particular the distribution of displacement on the fault network in space and time and the apparent abandonment of large parts of the network as tectonic activity became focussed within a relatively narrow basin in the last one million years. The narrowness of the fault blocks (4 to 8 km wide) is also a topic of debate. Course Outline Competence Level: N144: Rift Systems, Faulting and 5 Days Skilled Fault-Controlled Sedimentary Architecture: Gulf of Corinth Field Course (Greece) Classroom Elements Instructor(s): Mary Ford and Ed Williams Low Physical Demand Theme 2 The stratigraphic architecture and facies distribution within the Plio-Pleistocene syn-rift stratigraphy. Particular attention has been focused on the giant Gilbert-type fan delta systems. Exercise topics and practical work that will be taught with this fieldtrip: Geometry and kinematics of extensional fault systems. Interpretation of rift geometries and successions. Lithostratigraphy of rifts. Typical facies and thickness distributions in space and time. Geodynamics of rifts (theoretical analysis of processes involved in rift evolution. syn-rift, post-rift phases, necking, the uniform stretching model and more recent models). Cross-section construction based on field observations, reconstruction of the Corinth rift history. Itinerary The course will undertake field excursions to the Vouraikos Valley, Kerinitis Valley, Krathis valley and Derveni area, all within 1 hour’s drive from the hotel. Participants will construct cross-sections and make stratigraphic correlations across a series of fault blocks, each with a different geometry and stratigraphic architecture. Day 0: Assemble at Athens airport, travel to the Gulf of Corinth with short visit to the Corinth canal. Check in to hotel at Elaionas, followed by Course Introduction, and Safety Brief. Day 1: General overview and introduction to the Corinth Rift. Geometry and stratigraphy of a single fault block (Trapeza, Ano Diakofto, Asomati Plateau, West Helike Fault) Day 2: Vouraikos section: Fault block geometry and stratigraphic architecture (Mikros church, Doumena east, Kato Zachlorou, Megha Speleo, Kalavryta road junction, Railway crossing) Day 3: Krathis section: relay ramp evolution, lateral variations in rift infill and fault geometries (Bridge to Kalamia and Bougsismos, Vallimi North, Tsivlos road exercise,Tsivlos Lake, Mavra Litharia, Krathis-Diakopto Road corals) Course Outline Competence Level: N144: Rift Systems, Faulting and 5 Days Skilled Fault-Controlled Sedimentary Architecture: Gulf of Corinth Field Course (Greece) Classroom Elements Instructor(s): Mary Ford and Ed Williams Low Physical Demand Day 4: The Keranitis Gilbert-type fan delta (Aghio Andreas area, Keranitis valley) Day 5: Eastern rift and its Gilbert deltas and prodelta turbidites (Evrostini delta panorama, Medourianika south, Evrostina road). Travel to Athens, final group dinner. Day 6: Depart Athens. Course Outline.