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Stratigraphy, Chemistry And Petrogenesis Of Volcanic Rocks Of The Mid-Tertiary Boot Heel Volcanic Field, Southwestern New Mexico And Southeastern Arizona, Charles R. Bryan Nov 1995

Stratigraphy, Chemistry And Petrogenesis Of Volcanic Rocks Of The Mid-Tertiary Boot Heel Volcanic Field, Southwestern New Mexico And Southeastern Arizona, Charles R. Bryan

Earth and Planetary Sciences ETDs

The mid-Tertiary Boot Heel volcanic field is located in the Basin and Range Province of southwestern New Mexico and southeastern Arizona. The field is defined on the basis of nine regional ash-flow tuffs, which have been correlated throughout the area, and for which probable source cauldrons have been identified. These tuffs are: tuff of Woodhaul Canyon (35.3 Ma); Bluff Creek Tuff (35.1 Ma); tuff of Steins (34.4 Ma); Oak Creek Tuff (33.5 Ma), tuff of Black Bill Canyon (stratigraphically constrained to 32.7-33.5 Ma); Gillespie Tuff (32.7 Ma); tuff of Horseshoe Canyon (27.6 Ma); Park Tuff (27.4 Ma); and Rhyolite Canyon …


Palynological Characteristics Of Near-Shore Shell-Bearing Pliocene Through Holocene Sediments Of Florida, Georgia, And South Carolina, Fredrick J. Rich Nov 1995

Palynological Characteristics Of Near-Shore Shell-Bearing Pliocene Through Holocene Sediments Of Florida, Georgia, And South Carolina, Fredrick J. Rich

Earth, Environment & Sustainability: Faculty Publications

Seventeen pollen-bearing samples· from sites in South Carolina, Georgia, and Florida were analyzed for their pollen content. The samples range in age from Late Pliocene to Holocene. The initial objective of the study was to use the samples to help define the age of the physiographic feature known as Trail Ridge. All samples were marine sediments, and many were from marine mollusk-dominated strata. Pollen of Pinus and Quercus were abundant in all samples; Taxodium was abundant in about half of them. Carya, Liquidambar, Compositae, Gramineae, and ChenopodiaceaeAmaranthaceae were present as accessory taxa. Dinoflagellate cysts, microforams, and pyrite were present, or …


Groundwater Study: Toyota Motor Manufacturing, Usa Georgetown, Kentucky, Gary Felton, Lyle V. A. Sendlein, Teri Dowdy, Daryl Hines Nov 1995

Groundwater Study: Toyota Motor Manufacturing, Usa Georgetown, Kentucky, Gary Felton, Lyle V. A. Sendlein, Teri Dowdy, Daryl Hines

KWRRI Research Reports

An eighteen month study of the Toyota Motor Manufacturing (TMM) plant site and the surrounding area was undertaken. The basic charge for this project was to characterize the groundwater that is potentially impacted by the TMM plant site. This included occurrence, flow direction, and, if possible, velocity. Because the area is karstified (has sinkholes, springs, caves, etc.) surface water and groundwater are intimately connected and, hence, surface water was frequently an important component of this work.

Data from TMM construction plans and monitoring work done subsequent to construction were elicited from the various repositories within the TMM infrastructure. Aerial color …


Geochemistry Of The Boring Lava Along The West Side Of The Tualatin Mountains And Of Sediments From Drill Holes In The Portland And Tualatin Basins, Portland, Oregon, Michelle Lynn Barnes Oct 1995

Geochemistry Of The Boring Lava Along The West Side Of The Tualatin Mountains And Of Sediments From Drill Holes In The Portland And Tualatin Basins, Portland, Oregon, Michelle Lynn Barnes

Dissertations and Theses

Instrumental Neutron Activation Analysis (INAA) was used to identify geochemical groups in Boring Lava along the west side of the Tualatin Mountains, and in sediments of the Portland and Tualatin basins. Samples of Boring Lava were obtained from TriMet drill core collected during planning of the tunnel alignment for the Westside Light Rail line. Additional samples of Boring Lava were collected from outcrops along the west side of the Tualatin Mountains. Samples of sediment from the Tualatin and Portland basins were obtained from drill core collected during an Oregon Department of Geology and Mineral Industries (DOGAMI) Earthquake Hazards Mapping project. …


"A Geological Interpretation Of The Stanley Fault And Other Thrust Faults In Page County, Virginia", Michael James Sarros Oct 1995

"A Geological Interpretation Of The Stanley Fault And Other Thrust Faults In Page County, Virginia", Michael James Sarros

OES Theses and Dissertations

Paleozoic carbonate rocks flooring Page Valley (within Page County) are overthrust by Precambrian to Cambrian elastic rocks of the Blue Ridge to the east of the study area. King (1950) recognized that the Cambrian carbonate sequence of Page Valley, near Stanley, Virginia, is broken by a large transverse fault which he named the Stanley fault. King (1950) interpreted the Stanley fault as a high-angle reverse fault with oblique-slip displacement. However, detailed mapping and structural data collected in this study indicate the Stanley fault is a low angle thrust fault which cuts all pre-Alleghanian and Early Alleghanian structures.

Two previously unrecognized …


An Improved Method For Determining And Characterizing Alignments Of Point-Like Features And Its Implications For The Pinacate Volcanic Field, Sonora, Mexico, Tim Lutz, J T. Gutmann Sep 1995

An Improved Method For Determining And Characterizing Alignments Of Point-Like Features And Its Implications For The Pinacate Volcanic Field, Sonora, Mexico, Tim Lutz, J T. Gutmann

Earth & Space Sciences Faculty Publications

We present an improved method for determining statistically significant alignments of pointlike features. One of the principal such methods now in use, the two-point azimuth method, depends on a homogeneous distribution of points over the region of interest. Modification of this approach by use of the relatively new statistical technique of kernel density estimation permits treatment of heterogeneous point distributions without introducing substantial dependence on choice of the grid employed in the test for significance of apparent preferred orientations. The improved method can selectively reveal alignments on different spatial scales and can suggest the locations of alignments as well as …


Comments On “Measurements Of 7Be And 210Pb In Rain, Snow, And Hall”, M. Baskaran Sep 1995

Comments On “Measurements Of 7Be And 210Pb In Rain, Snow, And Hall”, M. Baskaran

Environmental Science and Geology Faculty Research Publications

No abstract available


Constraints On Present-Day Basin And Range Deformation From Space Geodesy, Jeffrey Lee, Timothy H. Dixon, Stefano Robaudo, Marith C. Reheis Aug 1995

Constraints On Present-Day Basin And Range Deformation From Space Geodesy, Jeffrey Lee, Timothy H. Dixon, Stefano Robaudo, Marith C. Reheis

All Faculty Scholarship for the College of the Sciences

We use new space geodetic data from very long baseline interferometry and satellite laser ranging combined with other geodetic and geologic data to study contemporary deformation in the Basin and Range province of the western United States. Northwest motion of the central Sierra Nevada block relative to stable North America, a measure of integrated Basin and Range deformation, is 12.1±1.2 mm/yr oriented N38°W±5° (one standard error), in agreement with previous geological estimates within uncertainties. This velocity reflects both east-west extension concentrated in the eastern Basin and Range and north-northwest directed right lateral shear concentrated in the western Basin and Range. …


Deep-Well Data Base For Nebraska, Duane R. Mohlam, Raymond R. Burchett Aug 1995

Deep-Well Data Base For Nebraska, Duane R. Mohlam, Raymond R. Burchett

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Data From The Deep-Rock Samples On File From Wells Drilled In Nebraska, Duane R. Mohlman Jul 1995

Data From The Deep-Rock Samples On File From Wells Drilled In Nebraska, Duane R. Mohlman

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


The Distribution Of Naturally Occurring Soil Radionuclides And Radon Potential Of Northwest Oregon, Stuart Graham Ashbaugh Jun 1995

The Distribution Of Naturally Occurring Soil Radionuclides And Radon Potential Of Northwest Oregon, Stuart Graham Ashbaugh

Dissertations and Theses

Radon, a naturally occurring radioactive gas produced as one of the decay products of soil/rock uranium and thorium, is considered to be a leading cause of pulmonary disease. Gamma spectrometry of 146 samples of soil were used to quantify radon source potential relative to lithology by measuring Bi214 activity of the U238 decay series. Additional soil radio nuclide data (Th232, Ac228, K40 and C137 ) were used to help identify regional source provenance geochemistry and soil development. Ac228, Bi214 and Th232 activities in northwest Oregon soils range from five …


A Hydrologic Analysis Of Government Island, Oregon, Scott Gregory Bittinger May 1995

A Hydrologic Analysis Of Government Island, Oregon, Scott Gregory Bittinger

Dissertations and Theses

Government Island, located in the Columbia River approximately 16 km (10 mi) upstream of the confluence with the Willamette River, is a wetland mitigation site prompted by expansion of the southwest quadrant of Portland International Airport. The purpose of the study is to predict water levels in two enclosed lowland areas, Jewit Lake and Southeast Pond, based on levels of the Columbia River, precipitation, and evapotranspiration. Mitigation is intended to convert 1.13 km2 (237 acres) of seasonally flooded wetland to 1.27 km2 (267 acres) of semi-permanently flooded wetland and seasonally flooded wetland.

Flooding of the wetland is most …


The Quaternary Geology Of The Eastern Side Of The Greys River Valley And The Neotectonics Of The Greys River Fault In Western Wyoming, L. C. Allen Jones May 1995

The Quaternary Geology Of The Eastern Side Of The Greys River Valley And The Neotectonics Of The Greys River Fault In Western Wyoming, L. C. Allen Jones

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Greys River fault is the easternmost active normal fault associated with Basin and Range extension in the lntermountain seismic belt. It is a north-south trending normal fault, located in the Sevier-age fold and thrust belt of western Wyoming, and bounds the west side of the Wyoming Range. The fault is at least 54 km long, and juxtaposes Permo-Pennsylvanian Wells Formation against various Triassic formations. Throw ranges from 100-1000 m. Seismic reflection data suggest that the Greys River fault is a listric normal fault that soles into the Darby thrust at depth. The fault offsets late Quaternary deposits on the …


Groundwater And Surface-Water Interactions Along Lower Medano Creek, Great Sand Dunes National Monument, Colorado, Gregg L. Hadlock May 1995

Groundwater And Surface-Water Interactions Along Lower Medano Creek, Great Sand Dunes National Monument, Colorado, Gregg L. Hadlock

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The objectives of this investigation are as follows: 1) review the existing hydrogeologic data for the San Luis Valley, the Great Sand Dunes Monument, and Medano Creek; 2) review the surface-water data that have been collected on Medano Creek; 3) collect or review previously collected water-level data obtained in the area of lower Medano Creek and correlate them with the surface-water data; 4) conduct constant-head permeameter tests on sand samples collected near the ground surface along lower Medano Creek; 5) produce a conceptual model of lower Medano Creek; and 6) produce a numerical model of lower Medano Creek that will …


Late Quaternary Glacial Geology, Shoreline Morphology, And Tephrochronology Of The Lliamna/Naknek/Brooks Lake Area, Southwestern Alaska, Karen B. Stilwell May 1995

Late Quaternary Glacial Geology, Shoreline Morphology, And Tephrochronology Of The Lliamna/Naknek/Brooks Lake Area, Southwestern Alaska, Karen B. Stilwell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study focuses on the late-Wisconsin Brooks Lake glaciation, lake-level fluctuations, and volcanic deposits in the lliamna/Naknek/Brooks Lake area on the northern Alaska Peninsula, southwestern Alaska. The Brooks Lake glaciation consists of five stades, from youngest to oldest: Kvichak, Iliamna, Newhalen, Iliuk, and Ukak. This thesis reassigns the type Mak Hill moraine to a pre-late-Wisconsin glaciation, and considers the moraine enclosing Naknek Lake an early-late-Wisconsin deposit correlative to either the Kvichak stade, lliamna stade, or both. The presence in the Iliamna Lake valley, and the absence in the Naknek Lake valley of a two-fold earliest-late-Wisconsin Kvichak/Iliamna glacial sequence suggest that …


Analysis Of Perched Groundwater Bodies Beneath The Radioactive Waste Management Complex At The Idaho National Engineering Laboratory, Alan V. Jones May 1995

Analysis Of Perched Groundwater Bodies Beneath The Radioactive Waste Management Complex At The Idaho National Engineering Laboratory, Alan V. Jones

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The migration of radionuclides and volatile chemicals through a thick sequence of unsaturated basalts and sedimentary interbeds has been documented in the Subsurface Disposal Area (SDA) at the Radioactive Waste Management Complex (RWMC) of the Idaho National Engineering Laboratory (INEL). The three mechanisms by which this migration may have occurred are seasonal infiltration from the ground surface within the SDA; flood events in 1962, 1969, and 1982; and the lateral movement of water from the spreading areas located nearby. It is currently thought that the contaminants migrated through the unsaturated sediments and basalt flows during the three flood events.

Transducers …


A Petrographic And Fluid Inclusion Study Of The Purple Vein And Post/Betze Orebodies, Carlin, Nevada, Jan B. Lamb May 1995

A Petrographic And Fluid Inclusion Study Of The Purple Vein And Post/Betze Orebodies, Carlin, Nevada, Jan B. Lamb

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Purple Vein (Meikle Mine) and Post/Betze orebodies, two Carlin-type, gold deposits, display important differences in size, alteration, silicification, pyritization, and gold grade. A core hole was examined from each deposit to gather petrographic and microthermometric data to determine the mineral paragenesis, to determine fluid pressure, temperature, and composition to compare of the two orebodies, and to determine depths of formation.

The parageneses determined were divided into three stages. (1) The Early Mineralization Stage contains quartz, pyrobitumen, barite, sphalerite, sulfosalts, quartz, and pyrite in the Purple Vein deposit and consists of calcite in the Post/Betze deposit. High salinity basinal brines, …


An Understanding Of Factors Controlling Isotopic Ratios Of Wine As A Potential Surrogate Of Past Precipitation, Eric Alan Caldwell May 1995

An Understanding Of Factors Controlling Isotopic Ratios Of Wine As A Potential Surrogate Of Past Precipitation, Eric Alan Caldwell

UNLV Theses, Dissertations, Professional Papers, and Capstones

Precipitation, vapor water, ground water, soil water, grape berry and grape leaf water, grape must, and vintage wines were collected from northern California for stable isotopic analysis. An understanding of factors controlling isotopic ratios of wine allows evaluation of wine as a surrogate of past precipitation. Stable isotopic compositions of grape berry waters collected at Charles Krug Winery in Napa Valley. CA range from -31 to -17 per mil in 8D and +7.2 to +15.3 per mil in 8180, and plot along a transpiration line of slope 2. 7. Grape leaf waters range from -25 to +5 per mil in …


Geology Of The Ogallala/High Plains Regional Aquifer System In Nebraska: Field Trip No. 6, Robert F. Diffendal Jr. Apr 1995

Geology Of The Ogallala/High Plains Regional Aquifer System In Nebraska: Field Trip No. 6, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

This guide is mostly figures with a reference section containing some of the pertinent literature on the Cenozoic geology we will see over the next four days. We will make all 17 stops if the weather is reasonably good and the roads are passable. On the first day, April 29, we will try to get to stops 1–5, the more distal parts of the Ogallala and younger deposits in Nebraska. On April 30, we will try to visit stops 6–9. Stops 10–15, in areas closer to the sediment sources of the Ogallala and some of the younger units, will be …


A Feasibility Study For Using Computerized Water Well Records To Delineate Areas Of Recharge-Discharge Potential, Lauren D. Hughes Apr 1995

A Feasibility Study For Using Computerized Water Well Records To Delineate Areas Of Recharge-Discharge Potential, Lauren D. Hughes

Masters Theses

A method for delineating areas of recharge-discharge potential has been developed utilizing computerized water well records. The methodology is based on the vertical head differences found between wells with shallow depths of submergence and those with deeper depths of submergence. The residual values generated represent the magnitude of vertical potential and can be contoured to delineate areas of recharge-discharge potential. Well data were obtained from the Kalamazoo County Groundwater Database. Well selection was based on depth of submergence and total well depth.

The methodology was tested in Texas and Schoolcraft Townships, the Donnell Lake Study Area, and Kalamazoo County. Regularly …


Geophysical Investigation At The Mouth Of The St. Joseph River Valley And Adjacent Lake Michigan Shoreline In St. Joseph And Benton Harbor, Michigan, David L. Seng Apr 1995

Geophysical Investigation At The Mouth Of The St. Joseph River Valley And Adjacent Lake Michigan Shoreline In St. Joseph And Benton Harbor, Michigan, David L. Seng

Masters Theses

A combination of geophysical methods were employed in an attempt to characterize a small section of the shoreline of the St. Joseph, Michigan, region of the Lake Michigan shoreline. Electrical resistivity and Ground Penetrating Radar profiles conducted along the shoreline and within the nearshore environment reveal a buried valley of the ancestral St. Joseph river. This valley represents incision of the channel during lowered lake levels at the end of the Pleistocene.

Lakeward dipping radar reflectors are identified throughout the study site. Within the buried valley the reflectors are not glacial till as is the case outside the inferred valley …


Hydrogeochemical Delineation Of A Groundwater Flow System, Berrien County, Michigan, Patrick J. Bartnik Apr 1995

Hydrogeochemical Delineation Of A Groundwater Flow System, Berrien County, Michigan, Patrick J. Bartnik

Masters Theses

The objective of this study was to examine the possibility of determining groundwater flow directions from natural variations in groundwater chemistry. Groundwater samples were analyzed for major cation and anion concentrations. These data were to have been contoured and then compared with groundwater flow maps generated by conventional methods. The purpose was to determine whether a correlation could be drawn between the two methods. However, the results of the study did not allow for this comparison.

The plotted major cation and anion data did not lend themselves to contouring, which suggests that greater control may be required during the selection …


Vertical Resolution Of A Seismic Survey In Stratigraphic Sequences Less Than 100 M Deep In Southeastern Kansas, Richard Daniel J. Miller, Neil Lennart Anderson, Howard Randall Feldman, Evan K. Franseen Apr 1995

Vertical Resolution Of A Seismic Survey In Stratigraphic Sequences Less Than 100 M Deep In Southeastern Kansas, Richard Daniel J. Miller, Neil Lennart Anderson, Howard Randall Feldman, Evan K. Franseen

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

A 400-m long, 12-fold high-resolution common depth point (CDP) reflection seismic profile was acquired across shallow converging Pennsylvanian strata in the Independence area of southeastern Kansas. One of the principal objectives was to determine practical vertical resolution limits in an excellent shallow seismic-data area with borehole control. The dominant frequency of the CDP stacked data is in excess of 150 Hz based on peak-to-peak measurements. Interference phenomena observed on stacked seismic data incorporated with models derived from log and drill-hole information suggest a practical vertical resolution limit of about 7 m, or one-third of the dominant wavelength. The data suggest …


Sks Splitting Beneath Southern California, Kelly H. Liu, Paul M. Davis, Stephen S. Gao Apr 1995

Sks Splitting Beneath Southern California, Kelly H. Liu, Paul M. Davis, Stephen S. Gao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Measurements of SKS phase splitting were obtained from nineteen seismic stations in southern California. The fast polarization directions are 53° at the southern end of the Great Valley, 82 ± 8° in the western Transverse Ranges and northern Peninsular Ranges, 95 ± 4° in Mojave Desert, and 70° on San Clemente Island. The splitting time ranges from 0.8 to 1.8 seconds, which is consistent with an anisotropic layer of 100 to 200 km thick for 4% anisotropy.


Late Cretaceous Foraminifera As Indicators Of Sequence Boundaries, Book Cliffs, Utah, U.S.A., Kimberly A. Smith Apr 1995

Late Cretaceous Foraminifera As Indicators Of Sequence Boundaries, Book Cliffs, Utah, U.S.A., Kimberly A. Smith

OES Theses and Dissertations

Foraminiferal assemblages were described from three different depositional settings within the Upper Cretaceous (Campanian) Blackhawk Formation of Utah (known marginal marine environments, known marine environments, and along a suspected sequence boundary). Assemblages from the known marginal marine setting (as defined by sedimentologic-stratigraphic criteria) consisted of entirely agglutinated taxa dominated by Textularia sp. A. Assemblages from the known marine environment consisted of a mix of calcareous and agglutinated species, dominated by calcareous species (e.g., Gavelinella talaria). The foraminiferal assemblages from these known environments provide independent evidence that these sampled areas are characterized by marginal marine and fully marine deposits.

The foraminiferal …


Task Ii Completion Report: Independent Groundwater Characterization And Monitoring Program In Boyd County Mar 1995

Task Ii Completion Report: Independent Groundwater Characterization And Monitoring Program In Boyd County

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


A Search For The Seasonal Variability On The Depositional Fluxes Of 7Be And 210Pb, M. Baskaran Feb 1995

A Search For The Seasonal Variability On The Depositional Fluxes Of 7Be And 210Pb, M. Baskaran

Environmental Science and Geology Faculty Research Publications

Investigations of the atmospheric fallout of 7Be and 210Pb in many places around the globe indicate that there are seasonal variations on the depositional fluxes of these nuclides: high in winter in a few places, while in most places the high occurs in spring. However, these earlier studies did not address quantitatively the corresponding seasonal variations of the amount of precipitation during these periods. Data on the depositional fluxes of 7Be and 210Pb in Galveston, Texas, during the years 1989–1991 indicate that the seasonal variation is not uniform from year to year, and the amount of …


1995, Spatial And Temporal Variability Of Late Neogene Equatorial Pacific Carbonate, T. K. Hagelberg, Nicklas G. Pisias, Larry A. Mayer, N. J. Shackleton, Alan C. Mix Jan 1995

1995, Spatial And Temporal Variability Of Late Neogene Equatorial Pacific Carbonate, T. K. Hagelberg, Nicklas G. Pisias, Larry A. Mayer, N. J. Shackleton, Alan C. Mix

Affiliate Scholarship

High-resolution, continuous records of GRAPE wet bulk density (a carbonate proxy) from Ocean Drilling Program Leg 138 provide one the opportunity for a detailed study of eastern equatorial Pacific Ocean carbonate sedimentation during the last 6 m.y. The transect of sites drilled spans both latitude and longitude in the eastern equatorial Pacific from 90° to 110°W and from 5°S to 10°N. Two modes of variability are resolved through the use of Empirical Orthogonal Function (EOF) analysis. In the presence of large tectonic and climatic boundary condition changes over the last 6 m.y., the dominant mode of spatial variability in carbonate …


Seismic Stratigraphy Of The Eastern Equatorial Pacific Ocean: Paleoceanographic Implications, Stephen F. Bloomer, Larry A. Mayer, Ted C. Moore Jr Jan 1995

Seismic Stratigraphy Of The Eastern Equatorial Pacific Ocean: Paleoceanographic Implications, Stephen F. Bloomer, Larry A. Mayer, Ted C. Moore Jr

Affiliate Scholarship

The collection of Leg 138 well-log and shipboard physical-property data, in conjunction with high-resolution seismic profiles, provides an opportunity to understand the paleoceanographic significance of seismic reflectors and to gain insight into the paleoceanographic evolution of the eastern equatorial Pacific Ocean. A series of eight reflectors or reflector packages were traced between two transects connecting five Leg 138 sites. By generating synthetic seismograms at each of these sites and comparing these to the field records, the origin of these seismic reflectors was determined in terms of physical-property variations and other core measurements. In particular, these reflectors were usually associated with …


Paleoceanography Of The Eastern Equatorial Pacific During The Neogene: Synthesis Of Leg 138 Drilling Results, Nicklas G. Pisias, Larry A. Mayer, Alan C. Mix Jan 1995

Paleoceanography Of The Eastern Equatorial Pacific During The Neogene: Synthesis Of Leg 138 Drilling Results, Nicklas G. Pisias, Larry A. Mayer, Alan C. Mix

Affiliate Scholarship

The primary objective of Leg 138 was to provide detailed information about the ocean's response to global climate change during the Neogene. Two north-south transects were drilled (95° and 110°W) within the region of equatorial divergence-driven upwelling (and thus high accumulation rates and resolution) and spanning the major equatorial ocean current boundaries (and thus recording a high-amplitude signal of the response of the sediment to climatically and/or tectonically driven changes in ocean circulation). The Neogene is marked by a number of well-known climatic and tectonic events (the closing of the Isthmus of Panama, the onset of North Atlantic Deep Water …