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The Holocene Carbonate Eolianites Of North Point And The Modern Marine Environments Between North Point And Cut Cay, Brian White, H. Allen Curran Jan 1985

The Holocene Carbonate Eolianites Of North Point And The Modern Marine Environments Between North Point And Cut Cay, Brian White, H. Allen Curran

Geosciences: Faculty Publications

The goals of this part of the field trip are to study the types of strata, sedimentary structures, trace fossils, and dune morphologies of the Holocene eolianites excellently exposed along the coasts of Rice Bay and North Point. We will show how eolian deposition of carbonate grains occurs and how dunes are initiated and evolve. Toward the end of this excursion, a short snorkel dive will be conducted in the shallow, sheltered waters between North Point and Cut Cay to study grass beds, sandy substrates, and hardgrounds and to compare their associated sediments, plants, and animals. The area to be …


The Use Of Ilmenite Element Composition For The Determination Of Provenance, Yu W. Tsang Jan 1985

The Use Of Ilmenite Element Composition For The Determination Of Provenance, Yu W. Tsang

OES Theses and Dissertations

Fifty three samples were taken from three major rivers and their tributaries in Virginia: the James, Roanoke. and Potomac-Shenandoah Rivers. Samples were obtained from the Valley and Ridge. Blue Ridge and Piedmont provinces. The possible source rock types for these samples were determined by comparison of tributary ilmenite composition with drainage basin rock types. Ilmenite element concentration varied with different rock types. Ti was usually high for the ilmenite derived from non-mafic igneous rocks. Mg and Cr were high for the ilmenite from mafic igneous rocks. Zn was low for metamorphic ilmenite. The ilmenite from sedimentary rocks tended to have …


Metamorphism In The Eastern Lac Seul Region Of The English River Subprovince, Ontario, Steve J. Chipera Jan 1985

Metamorphism In The Eastern Lac Seul Region Of The English River Subprovince, Ontario, Steve J. Chipera

Theses and Dissertations

The English River subprovince of the Superior Province, Canada, is a linear, east-west trending high-grade metamorphic belt which extends from Lake Winnipeg in the west, to the James Bay lowlands in the east. It is composed of two prominent lithologic domains: a northern sedimentary gneiss-migmatite domain, and a southern plutonic domain. The northern domain consists primarily of alternating migmatized layers of garnet-biotite "wacke" and garnet-cordierite-biotite "pelitic" metasediments. The southern domain is composed mainly of intermediate granitic to trondhjemitic plutons. Bordering to the north and south are the lower grade Uchi and Wabigoon greenstone belts. Metamorphism and migmatization occurred during the …


Depositional Environments And Diagenesis Of Carbonates And Associated Evaporites, Frobisher-Alida Interval, Madison Group (Mississippian), Williston Basin, Northwestern North Dakota, Thomas J. Obelenus Jan 1985

Depositional Environments And Diagenesis Of Carbonates And Associated Evaporites, Frobisher-Alida Interval, Madison Group (Mississippian), Williston Basin, Northwestern North Dakota, Thomas J. Obelenus

Theses and Dissertations

The Frobisher-Alida interval is a subsurface, marker-defined unit, one of several units designated for rocks of the Madison Group (Mississippian) in the Williston Basin of North Dakota. The Frobisher Alida conformably overlies the Tilston interval and is conformably overlain by the Ratcliffe interval. 1t attains a maximum thickness of a little over 400 feet (123 m) and thins to an erosional edge along the eastern margin of the Basin.

The Frobisher-Alida is composed of limestones, dolomitic limestones, and dolostones of the Mission Canyon Formation and anhydrites of the overlying Charles Formation which exist in a complex facies relationship within the …


Late Quaternary Environmental And Climatic History Of The Southern Chilean Lake Region Interpreted From Coleopteran (Beetle) Assemblages, John W. Hoganson Jan 1985

Late Quaternary Environmental And Climatic History Of The Southern Chilean Lake Region Interpreted From Coleopteran (Beetle) Assemblages, John W. Hoganson

Theses and Dissertations

A diverse Coleoptera fauna of 462 species in 48 families was collected from 41 locations in the Parque Nacional de Puyehue and adjacent parts of the Lake Region of southern Chile. The sample locations ranged from rain forest habitats at sea-level to Andean tundra habitats at 1500 m msl. Cluster analysis of a Dice similarity coefficient matrix revealed a broad pattern of bioassociations within the large data base, Boundaries between the bioassociations correspond largely with those of the major vegetation zones implying that the distribution of the fauna is strongly influenced by the distribution of plants. Evidence from fossils indicates …


The Geology And Hydrocarbon Potential Of The Dawson Bay Formation Carbonate Unit (Middle Devonian), Williston Basin, North Dakota, Wayne R. Pound Jan 1985

The Geology And Hydrocarbon Potential Of The Dawson Bay Formation Carbonate Unit (Middle Devonian), Williston Basin, North Dakota, Wayne R. Pound

Theses and Dissertations

The Middle Devonian Dawson Bay Formation carbonate unit is present in the subsurface of North Dakota except where truncated by post-depositional erosion. The carbonate unit thickens from the erosional limit to a maximum thickness of 47.5 m (156 ft.) in Renville County and reaches a maximum depth of 3798 m (12, 432 ft.) below the surface in McKenzie County. In North Dakota, a submarine hardground separates the carbonate unit from the underlying “Second Red Bed member” of the Dawson Bay Formation. The upper contact with the Souris River Formation is conformable except in those areas where the Dawson Bay Formation …


Palynology Of The Hagel Lignite Bed And Associated Strata, Sentinel Butte Formation (Paleocene), In Central North Dakota, Edward N. Steadman Jan 1985

Palynology Of The Hagel Lignite Bed And Associated Strata, Sentinel Butte Formation (Paleocene), In Central North Dakota, Edward N. Steadman

Theses and Dissertations

The Hagel bed is an economically important lignite and is the lowest named lignite in the Sentinel Butte Formation, Fort Union Group. The Hagel bed extends throughout the Knife River Basin coal-mining area of central North Dakota. Stratigraphic sections of the Hagel bed, including intercalated clastic rocks, were measured in the highwalls of the Center mine, Glenharold mine, and Falkirk mine.

Samples from the stratigraphic sections were described and analyzed, using standard palynological techniques, for their palynomorph content. Palynomorphs proved to be well preserved and abundant. Maceration of Hagel bed samples yielded a diverse collection of palynomorphs. A total of …


Hydrogeologic And Geochemical Factors Influencing The Impact Of A Chromium-Arsenic-Copper Wastewater Discharge On A Glacial Outwash Aquifer, Michael J. Gallagher Dec 1984

Hydrogeologic And Geochemical Factors Influencing The Impact Of A Chromium-Arsenic-Copper Wastewater Discharge On A Glacial Outwash Aquifer, Michael J. Gallagher

Masters Theses

A discharge of chromium-arsenic-copper laden wastewater occurred periodically from 1970 to 1980 at a wood preserving company located in southwestern Kalamazoo County, Michigan. As a result of this discharge, soils at the company site became contaminated with chromium, arsenic, and copper, and a local glacial outwash aquifer became contaminated with hexavalent chromium.

Soil samples collected from the discharge site were analyzed for clay-silt-sand-gravel content, organic matter, pH, clay mineralogy, and chromium, arsenic, copper, iron, and manganese content. Background soil samples were analyzed for most of the above catagories. Pearson r coefficients of correlation were calculated to determine the correlation of …


Geology Of A Section Of The Northwest Tobacco Root Mountains, Madison County, Southwest Montana, Kiff James Samuelson Dec 1984

Geology Of A Section Of The Northwest Tobacco Root Mountains, Madison County, Southwest Montana, Kiff James Samuelson

Masters Theses

The northwest Tobacco Root Mountains are located on the boundary between two major tectonic provinces: the fold and thrust belt and the Rocky Mountain foreland. Deformation typical of the Rocky Mountain foreland is present in the form of two major northwest trending faults with associated folds. Paleozoic rocks were passively draped over at least one of the elevated Precambrian blocks. Foliation of the Precambrian rocks also appears to have been gently folded in the process.

Folds and thrusts occur within the Precambrian and Paleozoic rocks, on the westernmost flank of the range, appearing to follow the general trend of the …


Geology Of Ponca State Park, Nebraska, Roger K. Pabian, Dennis R. Lawton Dec 1984

Geology Of Ponca State Park, Nebraska, Roger K. Pabian, Dennis R. Lawton

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


The Depositional History Of The Point Pleasant Member Of The Cynthiana Formation In Northern Kentucky, Gary J. Stefaniak Dec 1984

The Depositional History Of The Point Pleasant Member Of The Cynthiana Formation In Northern Kentucky, Gary J. Stefaniak

Masters Theses

Bioclastic limestones, siltstones, and shales of the Point Pleasant Member were deposited in a shallow marine environment immediately below normal effective wave base. High-energy conditions produced by storms lowered the effective wave base and stirred the bottom sediments and redistributed them into bedforms. The different types of contacts, distribution of the faunal groups, and fabrics permit inferences regarding energy levels and assignment of samples to a mode of deposition. Vertical and lateral trends were then deduced. High-energy conditions are believed to have occurred during Early and Late Point Pleasant time, whereas, low-energy conditions prevailed during deposition of the middle Point …


Late Tertiary Rodents From The Catamarca Province, Argentina : The Field Museum Collections, Lee A. Schremp Dec 1984

Late Tertiary Rodents From The Catamarca Province, Argentina : The Field Museum Collections, Lee A. Schremp

Loma Linda University Electronic Theses, Dissertations & Projects

The rodents collected in the 1920's by the Marshall Field Expedition for the Field Museum of Natural History, Chicago, are systematically reviewed and placed within the stratigraphic framework established at the time of collection. One new genus (Proeuryzygomys) and three new species (Abracoma intermedias, Proeuryzygomys diminutiva, and Cayiodon (Lelongia) catamarcensis) are proposed. Two distinct faunas are recognized corresponding to the Huayquerian and Montehermosan Land Mammal Ages respectively. Several computer programs were developed to aid in character analysis.


Geology Newsletter- 1984, Department Of Geology Nov 1984

Geology Newsletter- 1984, Department Of Geology

Geological and Environmental Sciences News

Vol.1 No.9

  • Dear Alumni and Friends
  • Advisory Council
  • Geology Development Fund
  • Graduate Students
  • Geology & Earth Science Club
  • W. David Kuenzi Scholarship Fund
  • 1983-84 Awards & Scholarships
  • Faculty News
  • Alumni News


Sulfur Dioxide And Particles In Quiescent Volcanic Plumes From Poás, Arenal, And Colima Volcanos, Costa Rica And Mexico, T. Casadevall, William I. Rose, William H. Fuller, William H. Hunt, Mark A. Hart, Jarvis L. Moyers, David C. Woods, Raymond L. Chuan, James P. Friend Oct 1984

Sulfur Dioxide And Particles In Quiescent Volcanic Plumes From Poás, Arenal, And Colima Volcanos, Costa Rica And Mexico, T. Casadevall, William I. Rose, William H. Fuller, William H. Hunt, Mark A. Hart, Jarvis L. Moyers, David C. Woods, Raymond L. Chuan, James P. Friend

Department of Geological and Mining Engineering and Sciences Publications

Measurements of SO2 emission rates and concentrations and of particle distribution, size, shape, and composition were made in quiescent volcanic plumes emitted into the troposphere from Poás and Arenal volcanos, Costa Rica, and Colima volcano, Mexico. SO2 emission rates were 700±180 metric tons per day (t/d) for Poás, 210±30 t/d for Arenal, and 320±50 t/d for Colima. The concentrations of SO2 calculated from the COSPEC/lidar data were 5–380 ppb. Concentrations of SO2measured directly by flame photometry were 10–250 ppb. Particles collected in the plumes with a quartz crystal microbalance impactor were mostly less than 3 …


Tectonic Implications Of Late Tertiary Strata Exposed Along The Piankatank River, Eastern Virginia, Daniel Stephen Lane Oct 1984

Tectonic Implications Of Late Tertiary Strata Exposed Along The Piankatank River, Eastern Virginia, Daniel Stephen Lane

OES Theses and Dissertations

Biostratigraphic analysis of Late Miocene and Pliocene strata along the Piankatank River in eastern Virginia exposes a juxtaposition of the Eastover and Yorktown Formations. This structure is situated on a NE trending alignment of geological, geomorphic, and geophysical features which run from southern Virginia to northern Delaware. Tectonic jointing in isolated sandstone bodies and fracture controlled drainage patterns provide further evidence of post-middle Pliocene tectonism in the region. The lateral spacing of this structure from the Stafford and Brandywine fault zones and other linear features on the Coastal Plain strongly implies that a structural similarity exists between the Piankatank structure …


Stratigraphy And Textural Analyses Of A Beach Ridge Complex, Cape Henry, Virginia, Daniel Leland Oyler Oct 1984

Stratigraphy And Textural Analyses Of A Beach Ridge Complex, Cape Henry, Virginia, Daniel Leland Oyler

OES Theses and Dissertations

Eight lithological units, documented from the analyses of 26 boreholes, comprise five laterally extensive horizons in the subsurface of Cape Henry, Virginia. Interpretations of the environments of deposition for those units are based upon textural and compositional features, fossils, thickness and distribution of strata, and previous reports about late Tertiary and Quaternary deposits in nearby areas. The incised, Pliocene Chowan River Formation (Unit H) underlies Pleistocene Units F and G which are concentrated in a buried river valley beneath Cape Henry. Estuarine Units D and E resulted from a marine transgression of the study area during the early Holocene. The …


Amatitlan, An Actively Resurging Cauldron 10 Km South Of Guatemala City, Richard L. Wunderman, William I. Rose Sep 1984

Amatitlan, An Actively Resurging Cauldron 10 Km South Of Guatemala City, Richard L. Wunderman, William I. Rose

Department of Geological and Mining Engineering and Sciences Publications

A 14×16 km diameter collapse caldera has been recognized 10 km south of Guatemala City, Guatemala. The caldera is north of the presently active volcano Pacaya and west of Agua, a large stratovolcano. The caldera was not previously recognized because its eastern and western margins coincide with faults that outline the Guatemala City graben and because the northern margin of the caldera is buried by pyroclastic rocks. The existence of the northern caldera margin is now established by gravity data and a variety of geological observations including circumferential faults, hot springs, well-log data, and lithological changes in sedimentary rocks. A …


Inventory Of Irrigation Water Use Box Butte County, Nebraska 1981, Dennis R. Lawton, Larry L. Teahon Jul 1984

Inventory Of Irrigation Water Use Box Butte County, Nebraska 1981, Dennis R. Lawton, Larry L. Teahon

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Barbados Ridge; Inner Trench Slope Sedimentation, William J. Cleary, H. Allen Curran, Paul A. Thayer Jun 1984

Barbados Ridge; Inner Trench Slope Sedimentation, William J. Cleary, H. Allen Curran, Paul A. Thayer

Geosciences: Faculty Publications

Quaternary sediments of this inner trench slope are chiefly foraminiferal-pteropod-nanno oozes that have been reworked and/or emplaced by gravity currents. These oozes are mixed with volcanogenic sediments and minor amounts of material derived from the insular shelf. Reworking occurs on topographic highs where fines are winnowed out and mass wasting and gravity currents are initiated; these processes ultimately result in the leveling of irregular floors of deeper, intervening slope basins. Petrographic analyses of graded intervals from the basin floors and slopes reveal the sands to be mixtures of planktic foraminifers (35%), pteropods (10%), and fresh, angular volcanic detritus (10-90%). On …


Groundwater Levels In Nebraska, 1983, Martin S. Johnson, Darryll T. Pederson Jun 1984

Groundwater Levels In Nebraska, 1983, Martin S. Johnson, Darryll T. Pederson

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Palynology And Age Of The Alvord Creek Formation, Steens Mountain, Southeastern Oregon, Stephen F. Barnett Jun 1984

Palynology And Age Of The Alvord Creek Formation, Steens Mountain, Southeastern Oregon, Stephen F. Barnett

Loma Linda University Electronic Theses, Dissertations & Projects

The age of the Alvord Creek Formation of Steens Formation, southeastern Oregon, has been a center of controversy since Axelrod's 1944 paleobotanical assignment of a Lower Pliocene age to the tuffaceous leaf-bearing shales. This date varies from earlier determinations by Chaney and MacGinitie that the flora was Mascall (Upper Miocene) equivalent. However, it is more sharply contradicted by the report of a Middle Miocene (Barstovian) fauna in the apparently overlying Steens Basalt and by a 21.3 m.y. radiometric date obtained on a basalt flow 61 meters above the leaf-bearing beds.

Palynomorphs recovered from three exposures of the leaf-bearing beds show …


Geology, Alteration And Mineralization Of A Silicic Volcanic Center, Glass Buttes, Oregon, Michael James Johnson May 1984

Geology, Alteration And Mineralization Of A Silicic Volcanic Center, Glass Buttes, Oregon, Michael James Johnson

Dissertations and Theses

Glass Buttes, a Pliocene silicic volcanic complex within the High Lava Plains province of Oregon, was erupted approximately 5.0 to 5.8 million years ago. Geologic mapping revealed that the eastern portion of the complex is underlain by rhyolitic glass domes, flows and rare pyroclastic flows. Basalt flows are interlayered with and onlap the silicic glass. Younger basalt flows, erupted from local vents, overlie silicic glass and onlapping basalts.

The eastern end of Glass Buttes is hydrothermally altered at the surface; a weak geothermal anomaly coincides with the altered areas. Alteration, localized by northwest trending normal faults, occurs primarily as opalite …


Enteric Contamination Of An Urban Karstified Carbonate Aquifer: The Double Springs Drainage Basin, Bowling Green, Kentucky, Geary Schindel May 1984

Enteric Contamination Of An Urban Karstified Carbonate Aquifer: The Double Springs Drainage Basin, Bowling Green, Kentucky, Geary Schindel

Masters Theses & Specialist Projects

Biological and chemical analysis of water samples, collected from surface and subsurface streams was preformed to determine the quantity and biologic sources of enteric contamination in the Double Springs Groundwater Basin, an urban karstified carbonate aquifer under Bowling Green, Kentucky. Major flow paths, drainage basin boundaries and geologic/hydrologic relationships were identified for the basin. Analysis of biologic contaminates using fecal coliform /fecal streptococcus counts and ratios were conducted for baseflow and storm events and related to the Double Springs hydrographs. Analysis was also conducted to determine the source of sulfides responsible for the growth of sulfur fixing bacteria in the …


A Bacteriological And Chemical Analysis Of Nonpoint Source Pollution In A Karst Aquifer Bowling Green, Kentucky, Wayne Green May 1984

A Bacteriological And Chemical Analysis Of Nonpoint Source Pollution In A Karst Aquifer Bowling Green, Kentucky, Wayne Green

Masters Theses & Specialist Projects

Monthly water samples collected from four sites in the Lost River Groundwater Basin, a shallow karst aquifer in the Bowling Green-Warren County area of Kentucky, represented samples from sites receiving conduit and diffuse flow. All sites were severely contaminated with bacteria, and on some occasions the surface water criteria for some heavy metals were exceeded.

Of the total 334 bacterial colonies identified 92.1% were verified as Escherichia coli by the API20E system. Acinetobacter calcoaceticus var. anitratum accounted for 2.10% of colonies; Citrobacter freundii for 0.30% Klebsiella pneumoniae for 0.90%; Klebsiella oxytoca, 0.90%; Citrobacter amalonaticus 0.30%; Enterobacter cloacae, 1.20%; …


Impacts Of Abandoned Surface Coal-Mined Lands On The Local Population In Southwestern Indiana, Fenner O. Omolo May 1984

Impacts Of Abandoned Surface Coal-Mined Lands On The Local Population In Southwestern Indiana, Fenner O. Omolo

All-Inclusive List of Electronic Theses and Dissertations

This study was involved with direct impact of abandoned surface coal-mined lands on the local population in southwestern Indiana. Five problem areas studied have a total of 237 acres of gob, 71 acres of slurry, 22 acres of spoil areas, 10 dangerous high walls, 13 acres of haul road, and 4 acres of tipple. Only three problem areas have postreclamation plans, while the rest do not. Pollution of lake #29 in Green Sullivan LK #29 problem area in Sullivan County and the lake west of Centenary in Electric Shovel problem area in Vermillion County has been caused by sediment and …


Petrology Of The Middle Jurassic Twin Creek Limestone, Lincoln And Sublette Counties, Southwestern Wyoming, David R. Raubvogel May 1984

Petrology Of The Middle Jurassic Twin Creek Limestone, Lincoln And Sublette Counties, Southwestern Wyoming, David R. Raubvogel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Twin Creek Limestone of Middle Jurassic age was studied in the Tunp, Salt River, and Wyoming Ranges in southwestern Wyoming. Modern carbonate environments and their ancient analogs were compared with information obtained from field study and petrographic analysis of samples of the Twin Creek Limestone in order to delineate environments of deposition, paleogeography, and diagenetic history.

Six major lithofacies were recognized: (1) carbonate mudstone; (2) carbonate mudstone breccia; (3) fossiliferous wackestone; (4) packstone-grainstone; (5) terrigenous mudstone; and (6) sandstone. These lithofacies were deposited in a variety of environments, including outer shelf platforms (carbonate mudstone and fossiliferous wackestone), oolitic sand …


Evaluation Of Low-Temperature Geothermal Potential In North-Central Box Elder County, Utah, Matthew C. Davis May 1984

Evaluation Of Low-Temperature Geothermal Potential In North-Central Box Elder County, Utah, Matthew C. Davis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to continue the assessment of low-temperature geothermal resources in Utah started by the Utah Geological and Mineral Survey. The area of interest with in this report is north-central Box Elder County, Utah. Exploration techniques used included chemical analyses of water from wells and springs, temperature surveys, and temperature-depth measurements in unused wells within the study area. The highest water temperatures (31, 30, and 29°C) recorded in this research were located in three separate geographic regions, suggesting that no single warm water occurrence dominates the study area.

Total dissolved solid (TDS) concentrations ranged from 294 …


Petrology Of The Middle Cambrian Ute Formation, North-Central Utah And Southeastern Idaho, Edward James Deputy May 1984

Petrology Of The Middle Cambrian Ute Formation, North-Central Utah And Southeastern Idaho, Edward James Deputy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Middle Cambrian Ute Formation was studied in the Bear River Range and the Wellsville Mountains of north-central Utah and southeastern Idaho. The depositional textures and sedimentary structures found within the rocks were compared with similar modern sediments and ancient rocks to determine depositional environments, paleogeography, and diagenetic alterations.

The rocks of the Ute Formation were divided into five basic types. These five rock types were formed within four identifiable lithofacies: 1) elastic marine shelf; 2) carbonate marine shelf; 3) agitated shoal; and 4) quiet-water shoal.

The sequence of elastic and carbonate sediments is believed to have been deposited in …


Structure And Petrology Of Tertiary Volcanic Rocks In Parts Of Toms Cabin Spring And Lucin Nw Quadrangles (Box Elder Co.), Utah, Bruce Edward Scarbrough May 1984

Structure And Petrology Of Tertiary Volcanic Rocks In Parts Of Toms Cabin Spring And Lucin Nw Quadrangles (Box Elder Co.), Utah, Bruce Edward Scarbrough

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A series of late Tertiary rhyolitic and dacitic flows, domes, and minor pyroclastic rocks form an elongate volanic mass along the northwestern Utah-northeastern Nevada border. The structure of the flow banding and the linear arrangement of vents indicate that the mass represents a multi-sourced extrusive complex which erupted through many fissure-type conduits. A 39 km2 area at the southern end of the mass was studied in detail in order to gain a better understanding of the eruptive nature and history of these Tertiary volcanic rocks. Age dating reveals that volcanism in the study area was episodic, and covered a …


Structural Geology Of The Northern Snowcrest Range, Beaverhead And Madison Counties, Montana, Mark Kenneth Sheedlo Apr 1984

Structural Geology Of The Northern Snowcrest Range, Beaverhead And Madison Counties, Montana, Mark Kenneth Sheedlo

Masters Theses

The Snowcrest Range was uplifted in Late Cretaceous and Early Tertiary time as a consequence of thrusting in Precambrian basement and Phanerozoic cover rocks.

The Snowcrest-Greenhorn thrust system is associated with largescale overturned, eastward verging folds. Mean orientation of the thrust system is N.40°E., 35°N.W.. The trend of the thrust system and associated transverse faults appear to be controlled by earlier structures. Mesoscopic and microscopic analyses indicate that metamorphic basement rocks accommodated congressional strain largely by brittle faulting and cataclastic shearing. Kinematic indicators suggest that local stresses were directed east-southeastward.

Northeast-trending Neogene faults along the western flank of the range …