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Articles 1 - 30 of 58
Full-Text Articles in Tectonics and Structure
Outcrop Analog For Lower Paleozoic Hydrothermal Dolomite Reservoirs, Mohawk Valley, Ny, Brian E. Slater
Outcrop Analog For Lower Paleozoic Hydrothermal Dolomite Reservoirs, Mohawk Valley, Ny, Brian E. Slater
Geology Theses and Dissertations
Geochemical analysis and field relations of linear dolomite bodies occurring in outcrop in the Mohawk Valley of New York suggest that they have undergone significant fault-related hydrothermal alteration. The dolomite occurs in the Lower Ordovician Tribes Hill Formation, which is regionally an early Ordovician shaley limestone with patchy dolomitization. The outcrop has an en echelon fault, fracture, and fold pattern. A 3D ground penetrating radar survey of the quarry floor has helped to map out faults, fractures, anticlines, synclines and the extent of dolomitization. Most of the dolomitization occurs in fault-bounded synclines or “sags” flanked by anticlines. The dolomite structures …
Mapping Of A Detachment Fault In Kythera Island And Study Of The Related Structural Shear Sense Indicators, Antonios Marsellos
Mapping Of A Detachment Fault In Kythera Island And Study Of The Related Structural Shear Sense Indicators, Antonios Marsellos
Geology Theses and Dissertations
Kythera Island is located on the prominent submarine horst between Crete and the Peloponnese in the southwestern part of the Aegean. The structure of Kythera is characterized by a pile of tectonic slices derived from different paleogeographic zones. The upper unmetamorphosed units comprise pelagic limestones and cherts of Pindos zone emplaced by thrusting in the Eocene on top of Tripolis zone neritic limestones. These units are separated from the lower metamorphosed unit of Phyllite-Quartzite (PQU) exposed in the northern part of Kythera by an extensional detachment fault of Late Miocene age. The lower tectonic unit of PQU was affected by …
Thermochronological Evidence For Neogene Incision Of The Rio Pativilca Canyon, Northern Peru, Matthew James Montario
Thermochronological Evidence For Neogene Incision Of The Rio Pativilca Canyon, Northern Peru, Matthew James Montario
Geology Theses and Dissertations
The Peruvian Andes have attained modern elevations of ~4000 m. Many peaks along the drainage divide are in excess of 5500 m with ~2-3 km of vertical relief, and canyons cut into the western edge have up to 3.5 km relief. The Rio Pativilica Canyon is cut into a folded Mesozoic marine sequence intruded by granitic rocks of the Coastal Batholith, which are overlain by Tertiary volcanics: this canyon has relief in excess of ~3 km. Based on geomorphological evidence, two episodes of valley incision cut the Puna erosional surface: 1) The Vallé stage, which is characterized by broad valleys …
Source Of Meta-Igneous Blocks And Structure Of The Colebrooke Schist In The Snowcamp Peak Area, Pickett Peak Terrane, Southwestern Oregon, Jennifer Katrib
Source Of Meta-Igneous Blocks And Structure Of The Colebrooke Schist In The Snowcamp Peak Area, Pickett Peak Terrane, Southwestern Oregon, Jennifer Katrib
Geology Theses and Dissertations
The Colebrooke Schist of the Pickett Peak terrane, southwestern Oregon, is the easternmost, structurally highest unit of the Late Mesozoic-Cenozoic Franciscan Accretionary Complex. The Colebrooke Schist consists of mostly transitional greenschist-blueschist-facies meta-sedimentary rocks with common blocks of meta-volcanics and serpentinites, rare talc-schists and meta-plutonic rocks. The Colebrooke Schist meta-volcanic blocks are greenstones, in many cases with visible relict pillow structures and relict igneous textures.
Fifteen meta-volcanic samples and one meta-plutonic sample were analyzed by XRF and ICP-MS and were plotted with analyses from Plake (1989) and Coleman (1972). The Colebrooke Schist meta-volcanic rocks plot in mid-ocean ridge basalt (MORB), island …
Structural Analysis Of The Gonic Formation In Berwick, Maine, Joseph F. Renda
Structural Analysis Of The Gonic Formation In Berwick, Maine, Joseph F. Renda
Geology Theses and Dissertations
RELATIONSHIP OF THE GONIC FORMATION AND NONSUCH RIVER FAULT TO THE NORUMBEGA FAULT ZONE IN BERWICK, MAINE
Located in southwestern Maine the Gonic Formation abuts the Nonesuch River Fault of the Norumbega Fault System. The rock types of the Gonic Fm. consist
predominantly of micaceous schist and lesser amounts of quartzite. Fieldwork suggests that the units have undergone transposition and thus appear to be
interlayered and pinch-out along strike. Granitoid rocks have also been observed and are interpreted as related to either the Lyman Pluton or White Mountain
Complex and serve as the backbone to the line of low-lying hills …
The Geology Of The Liberty-Orrington-Passagassawakeag/Fredericton Trough Terrane Boundary In The Bucksport-Orland Area, Coastal Maine, Heather A. Short
The Geology Of The Liberty-Orrington-Passagassawakeag/Fredericton Trough Terrane Boundary In The Bucksport-Orland Area, Coastal Maine, Heather A. Short
Geology Theses and Dissertations
The Liberty-Orrington fault separates two tectonic terranes of widely different lithologies and metamorphic grades within the Coastal Lithotectonic Belt of Maine. While the juxtaposition of the sillimanite-bearing Passagassawakeag gneiss and the chlorite grade Bucksport Formation (turbidites) requires a fault between them, field evidence for, and an understanding of, the nature of the fault has hitherto been lacking. Although the Liberty-Orrington fault has previously been interpreted as a thrust, strike-slip, and/or normal fault, the most recent debate has been centered around two models of Acadian amalgamation involving thrusting of the Passagassawakeag terrane from the southeast vs. thrusting from beneath central Maine …
Stratigraphy And Structure At The Southern End Of Lake Champlain In Benson, Vermont, Jennifer L. Granducci
Stratigraphy And Structure At The Southern End Of Lake Champlain In Benson, Vermont, Jennifer L. Granducci
Geology Theses and Dissertations
Detailed mapping and structural investigations in an area bound to the west by the Grenvillian basement of the Adirondack Mountains and to the east by the allochthonous slates of the Taconic Mountains led to the distinction of a Western Undeformed Zone and an Eastern Deformed Zone. The former is composed of the gently east-dipping shelf sequence of upper Cambrian to lower Ordovician clastics and carbonates which unconformably overlie the Precambrian basement. The latter is characterized by lower to middle Ordovician carbonates, striking roughly north-south and dipping predominantly to the east, which are overlain by well-cleaved shales and slates. The stratigraphic …
The Champlain Thrust System In Northwestern Vermont - Structure And Lithology Of The Taconic Foreland Sequence In The Highgate Center Quadrangle, Michael Roger Haschke
The Champlain Thrust System In Northwestern Vermont - Structure And Lithology Of The Taconic Foreland Sequence In The Highgate Center Quadrangle, Michael Roger Haschke
Geology Theses and Dissertations
The Champlain Thrust System, responsible for the final emplacement of the Taconic Allochthon, and which represents the surface trace of the main detachment under the Taconic suite, can be traced throughout the study area in northwestern Vermont, northward into southern Quebec. In the Highgate and St. Albans area this imbricated assemblage consists of 3 main carbonate thrust slices (Highgate Springs-, Philipsburg-, Rosenberg slice), each of which contain rocks deposited during some part of early Cambrian to medial Ordovician time. The Highgate Springs sequence comprises a mildly deformed early to medial Ordovician carbonate-shale succession. Late Cambrian to early Ordovician carbonates of …
Structure And Tectonic Significance Of Deformed Medial Ordovician Flysch And Melange Between Albany And Saratoga Lake And In The Central Hudson Valley, New York, Andreas Plesch
Geology Theses and Dissertations
The belt of medial Ordovician deformed flysch west of the traditionally defined Taconic boundary thrust was investigated by detailed mapping in the Capital District, from Albany to Saratoga Lake, and large scale compilation of the central Hudson Valley, between Glens Falls and Middletown. Maps and detailed sections are presented. Mapping recognized a two-fold division into a western belt of folded and faulted flysch and an eastern belt which is dominated by tectonic melange. The Folded and Faulted Flysch unit shows northward fining from greywacke-dominated to shale-dominated. Isoclinal folding and incipient melanges are characteristic in the south, whereas in the north …
A Paleoseismic Investigation Of The Mcgregor Fault, East-Central New York, Steven J. Tice
A Paleoseismic Investigation Of The Mcgregor Fault, East-Central New York, Steven J. Tice
Geology Theses and Dissertations
The structural disposition and movement potential of the McGregor Fault System in Eastern New York State are reviewed from the perspective of a paleoseismic investigation. The McGregor Fault zone has been located beneath deltaic sediments west of West Glens Falls using commercial and residential bore hole data and microgravity surveys. A 34 m long trench was excavated in overburden near the western margin of the McGregor Fault zone to a depth of 3.2 m. Stratified fluvially deposited sediments were exposed which showed no evidence of earthquake induced deformation or offset. However, the overburden present here does not possess optimal qualities …
A Kinematic Study Of The Summit Valley Plutonic Complex, Klamath Mountains, California, Nancy E. Griesau
A Kinematic Study Of The Summit Valley Plutonic Complex, Klamath Mountains, California, Nancy E. Griesau
Geology Theses and Dissertations
The Summit Valley plutonic complex (SVPC) is a multi-phase intrusive body of Late Jurassic age. Crystallization age for a zircon of 150±1 Ma and a cooling age for a hornblende of 144±1 Ma indicate a protracted period of high temperature. The SVPC is irregularly shaped, covers <15 km2, and is believed to be in the western limb of a post-Nevadan syncline, with an easterly dip estimated at about 45°. The SVPC penetrated the Orleans Fault and intruded and contact metamorphosed the upper and lower plates of the thrust. The Orleans Fault is a major tectonic boundary separating the Western Paleozoic …
The Geology Of The Vermont Valley And The Western Flank Of The Green Mountains Between Dorset Mountain And Wallingford, Vermont, Rolf Herrmann
The Geology Of The Vermont Valley And The Western Flank Of The Green Mountains Between Dorset Mountain And Wallingford, Vermont, Rolf Herrmann
Geology Theses and Dissertations
The carbonate sequence of the Vermont Valley has been generally believed to lie on the east limb of a major unfaulted syncline ("Middlebury Synclinorium"), and the exposed Precambrian basement and overlying cover rocks of the Green Mountain massif on the west limb of the adjacent major unfaulted anticline ("Green Mountain Anticlinorium"). Except for the Basal Thrust of the Taconic Allochthon, all faults shown on previous maps die out north of Dorset Mountain.
In contrast, detailed mapping for this thesis in the Vermont Valley and the western flank of the Green Mountain massif has revealed several major north/south trending thrust faults, …
Slickenside Petrography: Slip-Sense Indicators And Classification, Young-Joon Lee
Slickenside Petrography: Slip-Sense Indicators And Classification, Young-Joon Lee
Geology Theses and Dissertations
Petrographic study has been carried out on slickenside thin sections, to find out reliable microstructures for determining the slip-sense of faults, and to classify slickensides morphologically. Thin sections are made cut parallel to the striation and perpendicular to the slip plane. Many useful slip-sense indicators are found in thin section even though such indicators may be absent in hand specimens. They are (1) off-set or bending of once-continuous bodies such as veins, layers, grains or twin lamellae, (2) crystal fibers growing nearly parallel to the slip direction, (3) extensional fractures aligned oblique to the slip plane, (4) S-C geometries in …
Evaluation Of Computational Methods Of Paleostress Analysis Using Fault-Striation Data, Steven Henry Schimmrich
Evaluation Of Computational Methods Of Paleostress Analysis Using Fault-Striation Data, Steven Henry Schimmrich
Geology Theses and Dissertations
Over the past 12 years, many different computational methods or variations of existing methods have been proposed for determining paleostress tensors from fault populations and their slip directions. These methods are all based upon well-known relationships between stress and shear and use iterative, non-linear mathematical algorithms which seek to minimize the angles between the calculated maximum shear stress direction and the observed movement directions on each fault plane in a population. The solution returned is the best-fit paleostress tensor for the population.
By taking the Coulomb failure criterion into account, several paleostress analysis programs have been able to use linear, …
Geology And Structure Of The Rocks Associated With The Basal (Madstone) Thrust Of The Josephine Ophiolite In Southwestern Oregon: Evidence For A Metamorphic Sole, Kristin A. Grady
Geology And Structure Of The Rocks Associated With The Basal (Madstone) Thrust Of The Josephine Ophiolite In Southwestern Oregon: Evidence For A Metamorphic Sole, Kristin A. Grady
Geology Theses and Dissertations
Many ophiolites have amphibolite at their base which contains a sharp inverted grade of metamorphism. These metamorphic soles are thought to have formed during the detachment and emplacement of the ophiolite. In addition to the sharp inverted grade of metamorphism, other characteristics of metamorphic soles include 1). a highly strained peridotite unit of the hanging wall which has concordant structures with underlying amphibolite and 2). an underlying melange sequence and continental rocks.
The Madstone thrust displaces the Josephine peridotite (Josephine ophiolite-162 Ma) onto amphibolites and underlying deformed gabbros of the Chetco Intrusive Complex. The rocks associated with the Madstone thrust …
The Geology Of Taconic Thrust Sheets And Surrounding Carbonates Of The West Central Vermont Marble Belt, North Of Rutland, Vermont, Kay Bierbrauer
The Geology Of Taconic Thrust Sheets And Surrounding Carbonates Of The West Central Vermont Marble Belt, North Of Rutland, Vermont, Kay Bierbrauer
Geology Theses and Dissertations
The carbonates of the Vermont Valley and the overlying rocks of the Taconic sequence have been generally believed to lie on the east limb of a major unfaulted syncline (Middlebury Synclinorium). In this view a westward dipping, north-south trending basal Taconic overthrust must be exposed somewhere along the eastern margin of the Taconic Range.
In contrast, this study based on detailed mapping at the north end of the Taconic Allochthon suggests that a folded overthrust surface is only locally seen in fensters; more commonly the basal obduction surface of the Taconic Allochthon has been truncated by later cross-cutting thrust faults. …
Structural Geology Of The Northern Galice Formation, Western Klamath Mountains, Oregon And California, F. Ross Jones
Structural Geology Of The Northern Galice Formation, Western Klamath Mountains, Oregon And California, F. Ross Jones
Geology Theses and Dissertations
The Galice Formation is a thick, turbiditic flysch sequence that depositionally overlies the Josephine ophiolite in the western Klamath Mountains of northwestern California and southwestern Oregon. The Josephine ophiolite and Galice have been interpreted as the basement and sedimentary cover of a Late Jurassic back-arc basin that opened proximal to the continental margin. During the Nevadan orogeny (ca. 151-147 Ma), the ophiolite and overlying Galice sediments were thrust eastward beneath the continental margin along the regional Orleans fault. Two distinct Nevadan deformational phases are recognized in the Galice – an initial D1 or "main-phase" deformation and a later brittle deformation …
Sedimentology, Structure, And Geochemistry Of The Galice Formation: Sediment Fill Of A Back-Arc Basin And Island Arc In The Western Klamath Mountains, Rosann Park-Jones
Sedimentology, Structure, And Geochemistry Of The Galice Formation: Sediment Fill Of A Back-Arc Basin And Island Arc In The Western Klamath Mountains, Rosann Park-Jones
Geology Theses and Dissertations
The western Jurassic belt of the Klamath Mountains is an ideal locale for the study of ophiolite genesis, island arc development, and study of flysch deposition from a nearby eroding island arc and continental margin. Closure and imbrication of an inferred back-arc basin coincided with the Late Jurassic Nevadan orogeny (ca 150 Ma). The Galice Formation is the youngest formation involved in the Nevadan orogeny (Lanphere et al., 1968). In the type section in southwestern Oregon, the Galice structurally overlies the Rogue Formation volcaniclastics. The Rogue Formation has been previously interpreted as an island arc assemblage (Garcia, 1979). The type …
Structural Investigations On Experimentally And Naturally Produced Slickensides, Thomas Michael Will
Structural Investigations On Experimentally And Naturally Produced Slickensides, Thomas Michael Will
Geology Theses and Dissertations
This work has involved an experimental approach and a study of naturally produced slickensides.
The experiments, carried out on a pyrophyllitic rock, have been performed in order to define some extrinsic parameters that control surface and microstructural features. Normal stress, speed (i.e. strain rate), and amount of slip and total displacement were related to measureable surface features, such as length, and spacing between the developing ridges and grooves. Special attention was paid to a newly recognized type of slickenside lineation (Means, 1986). This lineation produced experimentally cannot be explained in terms of the traditional asperity ploughing or dissolution/precipitation models. It …
Petrology Of The Kula Volcanic Field, Western Turkey, Julie M. Dyer
Petrology Of The Kula Volcanic Field, Western Turkey, Julie M. Dyer
Geology Theses and Dissertations
The Kula volcanics are a small Pleistocene to Recent volcanic field located on the north shoulder of the Gediz graben, approximately 120 km east of Izmir. The field consists of a mixture of flows, small cones and pyroclastic deposits erupted during three periods of volcanic activity beginning about one million years ago. The volcanics range in composition from basanites to trachybasalts, commonly porphyritic with abundant clinopyroxene, olivine and amphibole phenocrysts. The lavas also host a wide variety of megacrysts, crustal xenoliths and hydrous mantle-derived nodules. These volcanics unconformably overlie Neogene lacustrine sedimentary rocks and the metamorphic basement rocks of the …
Structural Analysis Across The Northeast Boundary Of The Taconic Allochthon, West-Central Vermont, Thomas E. Hoak
Structural Analysis Across The Northeast Boundary Of The Taconic Allochthon, West-Central Vermont, Thomas E. Hoak
Geology Theses and Dissertations
The Taconic Allochthon is an elongate belt of Cambro-Ordovician, argillaceous sediments with lesser occurrences of calcareous and siliceous lithologies. These lithologically distinctive strata lie tectonically juxtaposed over a coeval medial-Ordovician carbonate shelf sequence. This geometry resulted from an arc-continent collision in which a westward-migrating arc (Ammonoosuc Volcanics) collided with an eastern North America passive margin and the accumulated accretionary prism of the forearc region was thrust onto the passive continental margin.
The present thesis examined the structural sequence at the north end of the Allochthon and the continuity of this sequence into the adjacent Parautochthonous Shelf strata. Structurally, the study …
Geology, Geochemistry, And Geochronology Of The Lems Ridge Olistostrome, Klamath Mountains, California, Matthias Ohr
Geology, Geochemistry, And Geochronology Of The Lems Ridge Olistostrome, Klamath Mountains, California, Matthias Ohr
Geology Theses and Dissertations
The Lems Ridge olistostrome (LRO), located within the western Jurassic belt of the Klamath Mountains geologic province, is a melange unit showing a distinct block-in-matrix fabric. The conformable relationship to both an igneous basement and the overlying flysch of the Late Jurassic Galice Formation points to a sedimentary origin. The lack of pervasive deformation and the internal stratification also support a predominantly olistostromal origin of the LRO. The matrix of the LRO consists of pebbly mudstone which interfingers with tuffaceous greenstone and tuff-breccias. Subordinate beds of chert, argillite, and sandstone are also present. The matrix contains abundant ophiolitic clasts, fragments …
Dolomitization Of The Hatch Hill Arenites And The Burden Iron Ore, Peter Michael Hofmann
Dolomitization Of The Hatch Hill Arenites And The Burden Iron Ore, Peter Michael Hofmann
Geology Theses and Dissertations
The Taconic allochthon is a sequence of Cambrian or Precambrian to Ordovician rocks. It is composed of predominantly deep water argillaceous and subordinate arenaceous and calcareous rocks that were deposited on the continental rise and slope. During the Ordovician, sediments which were earlier deposited in the slope-rise environment were incorporated into the accretionary prism of an island arc that approached from the east, and subsequently overthrust the carbonate platform.
The Hatch Hill Formation is part of the Taconic sequence. It consists of dominantly black-gray slates, minor amounts of sandstones and carbonates. Previous workers have recognized the presence of dolomite and …
Sedimentology And Tectonic Significance Of The Nutzotin Mountains Sequence, Alaska, Jane Kozinski
Sedimentology And Tectonic Significance Of The Nutzotin Mountains Sequence, Alaska, Jane Kozinski
Geology Theses and Dissertations
The Nutzotin Mountains Sequence, a Mesozoic flysch sequence in the eastern Alaska Range, was studied along the southern border and in the central portions of the outcrop belt. Three lithologic associations are recognized in the Bonanza Creek section (southern margin) that together indicate a coarsening-upward trend, suggestive of a prograding fan system. These associations are (from bottom to top): 1) debris flow conglomerates overlain by 500 m of intercalated mudstone and base-missing turbiditic siltstone, and mass movement features such as slump folds and slump horizons, 2) 195 m of thicker, coarser turbidites intercalated with mudstones; turbidites are graded but lack …
Geology Of The Frozen Ocean Lake - New Bay Pond Area, North-Central Newfoundland, Timothy M. Kusky
Geology Of The Frozen Ocean Lake - New Bay Pond Area, North-Central Newfoundland, Timothy M. Kusky
Geology Theses and Dissertations
Rocks of the Frozen Ocean Group outcrop in the Frozen Ocean Lake-New Bay Pond Area, Newfoundland, and are here divided into four formations. The Lewis Lake Formation forms the base of the Frozen Ocean Group, and is composed predominantly of mafic volcanic flows; this is conformably overlain by the Blue Star Formation which is entirely sedimentary in nature. The Blue Star Formation is in turn conformably overlain.by the Bursey Point Formation, which is a mixed volcanic and sedimentary unit. The top of the Frozen Ocean Group is marked by the Lynx Pond Formation, a mixed silicic- and mafic-volcanic formation, with …
The Tectonic Evolution Of The Eastern Yukon Tanana Upland, Alaska, Grant W. Cushing
The Tectonic Evolution Of The Eastern Yukon Tanana Upland, Alaska, Grant W. Cushing
Geology Theses and Dissertations
Field, structural, and isotopic studies in the southeastern Eagle Quadrangle reveal a complex Mesozoic history involving major metamorphism, fold development, thrusting, and igneous intrusion. These events may be related to the accretion of a terrane, possibly Stikine, to the North American continental margin.
40Ar/39Ar incremental heating experiments on metamorphic minerals from amphibolite facies rocks reveal Late Triassic to Middle Jurassic plateau ages interpreted as the age of major metamorphism. Large scale northeast trending folds within these rocks formed after the major metamorphism and before the intrusion of an undeformed, unmetamorphosed cross-cutting dike in Middle Jurassic. These folds probably developed in …
The Geology Of Ophiolitic And Adjoining Rocks Of Chagnon Mountain, Southern Quebec, Janet M. Harris
The Geology Of Ophiolitic And Adjoining Rocks Of Chagnon Mountain, Southern Quebec, Janet M. Harris
Geology Theses and Dissertations
Chagnon Mountain is located near the southern end of the Baie Verte-Brompton Line in the Eastern Townships of southern Quebec. The lithologic units in the area of study, from west to east and going up structure, are: gabbro, quartz-diorite, diabase, volcanics, the St. Daniel Formation and the Peasley Pond Conglomerate of the Glenbrooke Group. All these rocks have been metamorphosed to the greenschist facies. Contacts between the plutonic rocks are irregular and gradational indicating only one parent magma. Diabase dikes are present in the diabase unit and in the volcanics indicating the dikes acted as feeders to the volcanics. Geochemical …
The Influence Of Oceanic Transform Boundaries On The Generation And Evolution Of Oceanic Lithosphere, David G. Gallo
The Influence Of Oceanic Transform Boundaries On The Generation And Evolution Of Oceanic Lithosphere, David G. Gallo
Geology Theses and Dissertations
The first-order geologic and morphologic relationships at, along and proximal to ridge-transform-ridge plate boundaries are used to construct an empirical and speculative tectonic model. The geometry of a ridge-transform intersection necessitates the juxtaposition of relatively cold, thick lithosphere against the truncated end of an accreting plate boundary. The cold face of lithosphere cools the adjacent wedge of asthenosphere rising beneath the axis of accretion and restricts the amount of partial melting thus attenuating the amount of basaltic melt segregated from the asthenosphere per unit time. The manifestation of this cold edge effect is a thinner oceanic crust. At depth, upper …
Chatham Fault Zone, Old Chatham-East Chatham, New York: Mesostructures And Microstructures: Their Spatial And Age Relationships, Jorge Mora M.
Chatham Fault Zone, Old Chatham-East Chatham, New York: Mesostructures And Microstructures: Their Spatial And Age Relationships, Jorge Mora M.
Geology Theses and Dissertations
Detailed studies in rocks of Mettawee (Late Precambrian? to Early Cambrian) and Walloomsac (Middle Ordovician) slates between Old Chatham and East Chatham, New York, have shown that these rocks were intensely deformed during the Taconic orogeny and a later deformation event(?). Two generations of structures are clearly recognized in the area. The first generation (G1) includes tight west-verging folds whose axial plane foliation is the regional foliation slaty cleavage (S1). These structures are considered synchronous with the regional metamorphism of the Taconic orogeny and correlative with those structures belonging to the D2 deformation event proposed by Ratcliffe (1979) and Rowley …
Structure And Tectonics Of The Keban Metamorphics In The Northern Margin Of The Bitlis Suture Zone, Southeastern Turkey, Gültekin Savci
Structure And Tectonics Of The Keban Metamorphics In The Northern Margin Of The Bitlis Suture Zone, Southeastern Turkey, Gültekin Savci
Geology Theses and Dissertations
The study area near Keban consists of the allochthonous Keban division of the Keban-Malatya crystalline complex and the Yuksekova island-arc rocks of the Bitlis-Puturge Complex in the northern margin of the Bitlis Suture Zone. Detailed mapping shows that the Palaeozoic-Triassic Keban Metamorphics are composed of the following formations: (1) white, massive, karstic Kirklar Marble; (2) phyllitic psammite with calcschist interlayers Calik Formation; and (3) semi-crystallized gray Koyunatlayan Limestone. These formations define a tectonostratigraphy with the Kirklar Marble at the base and the Koyunatlayan Limestone at the top. The detailed lithological description of the Keban Metamorphic rock assemblages suggest that they …